QUESTOES – ONE

GLAUCOMA 1

1. Which of the following is a risk factor for developing primary angle-closure glaucoma (PACG)?

Male gender

Myopia

Short axial length

Young age

Feedback: Patients who develop PACG have small, crowded anterior segments and short axial lengths. The most important factors predisposing to PACG are a shallow anterior chamber, a thick lens, increased anterior curvature of the lens, a short axial length, and a small corneal diameter and radius of curvature. PACG occurs more commonly in hyperopic patients. PACG has been reported to be 2-4 times more common in women than men. The prevalence of PACG rises with increasing age.

2. One week after blunt trauma and hyphema, a patient with no previous history of glaucoma has a pressure of 40 mm Hg. Medical management has included levobunolol (Betagan), dorzolamide (Trusopt), homatropine 5%, and prednisolone acetate 1% qid. The least likely cause of the intraocular pressure elevation is:

Pupillary block

Blood obstructing the trabecular meshwork

Direct trauma to the trabecular meshwork

Corticosteroid-induced intraocular pressure elevation

Feedback: Shortly after blunt trauma, blood and inflammatory debris may clog the trabecular meshwork and raise the intraocular pressure. Direct injury to the trabecular meshwork can also occur, with angle recession a sign of that injury. A large clot can occlude the pupil, and extensive posterior synechia formation can cause a pupillary-block mechanism. Topical costeroid therapy may help control intraocular pressure by reducing inflammation and preventing the formation of peripheral anterior and posterior synechiae. A corticosteroid-induced intraocular pressure usually does not occur until at least 2-3 weeks after initiation of corticosteroid therapy. If there is visible blood and inflammatory debris in the anterior chamber, corticosteroid-induced intraocular pressure elevation should not be assumed to be playing an important role.

3. An elderly patient underwent an intracapsular cataract extraction many years ago. More recently, a full-thickness sclerectomy was performed in that eye for uncontrolled open-angle glaucoma. Now the patient presents having had pain and decreased vision for 2 days. Visual acuity is finger counting, the applanation tension is 7 mm Hg, there is no bleb and there is a large hypopyon. There is no view of the posterior segment. B-scan ultrasonography demonstrates substantial vitreous debris. Appropriate treatment would include all of the following except:

pars plana vitrectomy with intraocular antibiotic injection

vitreous tap for cultures

topical fortified antibiotic therapy alone

intravitreal antibiotic therapy

Feedback: In an aphakic eye or a pseudophakic eye with a disrupted or absent posterior capsule, intraocular infection from a bleb may quickly enter the vitreal cavity. The prognosis for such eyes is much worse than those with a \"blebitis.\"To date, there is no controlled study evaluating the treatment of late endophthalmitis in eyes with filtering blebs that is similar to the Endophthalmitis Vitrectomy Study (EVS), which evaluated the roles of pars plana vitrectomy and systemic antibiotics in treating postoperative endophthalmitis. Historical studies and reports have suggested that bleb endophthalmitis is often caused by Streptococcus pneumoniae or Haemophilus influenzae and, even with aggressive treatment, may have a poor outcome. At this time, treatment of this patient might include topical fortified antibiotic therapy, intravitreal antibiotic therapy, and vitrectomy with intraocular antibiotic injection.

4. A patient presents 2 years after a trabeculectomy during which mitomycin C was administered. She has had pain, redness, and discharge for 1day in that eye. Examination reveals a visual acuity of 20/200, applanation tension of 4 mm Hg, mucopurulent discharge, small bleb leak, and extensive cellular reaction in the anterior chamber with a small hypopyon. The lens and vitreous are clear. The most appropriate treatment at this time would be:

pars plana vitrectomy with intraocular antibiotic injection

topical fortified antibiotic therapy

injection of antibiotics the anterior chamber

intravenous antibiotic therapy

Feedback: In a patient with an infected bleb (blebitis) and anterior chamber reaction, topical fortified broad-spectrum antibiotic therapy would be the most appropriate initial treatment. In the presence of a clear vitreous, a pars plana vitrectomy with antibiotic therapy would not be necessary. Injection of antibiotics into the anterior chamber would also not be necessary. Intravenous antibiotic therapy would be no more effective and could arguably be less effective than topical fortified broad-spectrum antibiotic therapy. After the organism and its sensitivities have been identified, specific antibiotic therapy can be continued.

5. In which one of the following situations would intraoperative mitomycin C application during trabeculectomy be most clearly indicated?

A black patient

A patient with traumatic glaucoma with angle recession

A 25-year-old patient

A patient with previous unsuccessful glaucoma filtering surgery

Feedback: Antifibrosis agents (5-fluorouracil or mitomycin C) are beneficial when performing glaucoma filtering surgery in a patient with a history of previous cataract surgery or previous unsuccessful glaucoma filtering surgery. The 5-Fluorouracil Filtering Surgery Study demonstrated the benefit of postoperative subconjunctival 5-fluorouracil injections in these 2 groups of patients. Of the 4 choices provided, mitomycin C would be most strongly indicated in the patient with previous unsuccessful glaucoma filtering surgery. It is also possible that 5-fluorouracil or mitomycin C would benefit a patient with neovascular glaucoma (assuming panretinal photocoagulation has been performed) or ocular inflammatory disease. Although the use of mitomycin C would be less critical and possibly risk postoperative hypotony in a young or black patient, or in an individual with previous blunt trauma, 5-fluorouracil may be appropriate and a safer choice for some of these patients. Extent of glaucomatous visual loss and the need for a lower postoperative intraocular pressure may also affect the decision to use mitomycin C, 5-fluorouracil, or no antifibrosis agent.

6. A 56-year-old diabetic patient presents with pain and decreased vision to 20/80. Intraocular pressure is 58 mm Hg. There is mild corneal epithelial edema, iris neovascularization, a mild nuclear sclerotic cataract, and clear vitreous with visible proliferative diabetic retinopathy in that eye. After initiating medical therapy, the most important first step is:

Placement of a glaucoma implant

Cyclophotocoagulation

Trabeculectomy with intraoperative mitomycin C or postoperative subconjunctival 5-fluorouracil

Panretinal photocoagulation

Feedback: In an eye with neovascular glaucoma and proliferative diabetic retinopathy, after medical therapy is initiated, the most important first step is to perform a heavy panretinal photocoagulation (PRP). If the procedure is performed shortly after the development of neovascular glaucoma, there may be little permanent synechial angle closure, and the glaucoma may abate or be controlled medically. Once substantial synechial angle closure occurs, however, other forms of management in addition to PRP become necessary. If filtering surgery is performed, either as a trabeculectomy with or without antifibrosis therapy or as a glaucoma implant (seton), there is little chance of success and a high complication rate without some preceding retinal ablation and regression of rubeosis. In a highly inflamed eye with active neovascularization and acceptable intraocular pressure, there might be some benefit in delaying filtration surgery until some visible regression of the iris neovascularization occurs.

7. In an eye with a narrow angle, which of the following most strongly argues in favor of performing a laser peripheral iridotomy?

Amount of glaucomatous optic nerve cupping

Amount of glaucomatous visual field loss

Intraocular pressure level

Gonioscopic findings

Feedback: In chronic angle-closure glaucoma with relative pupillary block, gonioscopy is the key to diagnosis and management. Intraocular pressure may be normal or elevated. The presence of elevated pressure with a narrow angle alone does not indicate the need for a laser iridotomy. In this case, an open angle may be causing the intraocular pressure elevation with a coexistent narrow angle. In addition, the extent of visual field loss or optic nerve damage does not indicate whether an iridotomy is needed. Patients with appositional angle closure or areas of peripheral anterior synechiae with relative pupillary block have a high risk for developing chronic angle closure and should have a laser iridotomy.

8. Of the following, which would be the best initial medical agent for a patient with severe asthma and newly diagnosed glaucoma?

Dorzolamide (Trusopt)

Timolol (Timoptic, Betimol)

Carteolol (Ocupress)

Betaxolol (Betoptic)

Feedback: Nonselective beta-adrenergic antagonist therapy (carteolol, metipranolol, timolol) may precipitate increased shortness of breath or an asthma attack in patients with asthma. The selective beta-1 adrenergic antagonist betaxolol reduces the chance of this complication, but does not eliminate it in the severely asthmatic patient. Beta-receptor selectivity is relative and not absolute. In the patient presented, dorzolamide, a topical carbonic anhydrase inhibitor, would be the preferred medical option of the four listed. Latanoprost (Xalatan) is also indicated for first-line therapy. Other options are brimonidine (Alphagan), and less often used, dipivefrin (Propine) and pilocarpine.

9. The administration of topical ocular miotic (cholinergic) therapy in an eye with active intraocular inflammatory disease (uveitis) may increase all of the following except:

inflammation

uveoscleral outflow

posterior synechia formation

pain

Feedback: Topical ocular miotic (cholinergic) therapy increases trabecular outflow but decreases uveoscleral outflow. In an eye with active intraocular inflammatory disease, miotic therapy may cause increased pain, inflam-mation, and posterior synechia formation. In these eyes, miotic therapy should be avoided. Preferred medical management includes cycloplegic and corticosteroid therapy and glaucoma therapy other than miotics.

10. A 72-year-old woman presents with bilateral uncontrolled primary angle glaucoma and cataracts. Her best-corrected visual acuity is 20/40 OD and 20/60 OS. She complains of increasing difficulty driving and reading fine print. Intraocular pressure is 23 mm Hg bilaterally. Her current medications are carteolol (Ocupress) bid OU, latanoprost (Xalatan) qhs OU, and dorzolamide (Trusopt) tid OU. She has not tolerated pilocarpine in the past, stating it blurred and dimmed her vision.

She has no prior history of ocular laser or surgery. She has moderate visual field loss, with bilateral superior arcuate scotomas. Reasonable therapeutic choices at this time might include all of the following except:

cataract surgery

laser trabeculoplasty

trabeculectomy followed by cataract surgery at a later time

a combined cataract extraction and trabeculectomy

Feedback: This individual has uncontrolled, moderately advanced glaucoma in both eyes and visually significant cataracts. If the patient wishes to have cataract surgery, a combined cataract extraction with trabeculectomy would be a good therapeutic choice. Trabeculectomy can be performed first but would delay visual recovery until the time of a cataract surgery at a later date. If the patient is reluctant to have cataract surgery or glaucoma surgery at this time, laser trabeculoplasty would be a reasonable choice; however, over the long term, this may not adequately lower intraocular pressure. Laser trabeculoplasty would have a greater effect if performed before cataract surgery. Cataract surgery alone in an eye with uncontrolled glaucoma, on three medications, and with moderate visual field loss, would probably be the poorest therapeutic option among the four.

GLAUCOMA 2

1. Automated visual field testing has all of the following advantages except:

ability to compare statistically the current visual field with previous visual field tests

more patient-tester interaction

less training required for the tester (technician) than is the case with Goldmann visual field testing

greater standardization

Feedback: Automated threshold visual field testing is more standardized, allows comparison of current to previous visual field tests with statistical analyses, and requires less technical training for the person performing the visual field test than is the case with Goldmann manual perimetry. However, greater patient-tester interaction occurs with manual Goldmann perimetry than with automated perimetry. In automated perimetry, a computerized program presents the visual field test. Good patient preparation and instructions will however, help produce a better quality automated visual field test. Technician observation and encouragement during the test can improve the quality of an automated visual field test. New developments, including short wavelength automated perimetry, will increase the usefulness of this test.

2. Which of the following risk factors is probably the least significant for primary open-angle glaucoma?

myopia

level of intraocular pressure

family history

race or ethnic origin

Feedback: Although glaucoma is not equated with elevated intraocular pressure, intraocular pressure is probably the most important risk factor for visual loss. Family history and racial or ethnic background are also highly important risk factors. Black Americans have a greater prevalence of open-angle glaucoma at all ages. There is mounting evidence for the genetic basis of many of the glaucomas. Other factors, such as myopia and diabetes mellitus, are probably less important risk factors for primary open-angle glaucoma.

3. Which of the following was not demonstrated by the Glaucoma Laser Trial?

Laser-first-treated eyes had a slightly lower intraocular pressure than medication-first-treated eyes.

Most eyes in the laser-first group did not require medical therapy to control pressure.

Laser trabeculoplasty is about as effective as one glaucoma medical agent, timolol (Timoptic).

Laser-first-treated eyes had a slightly better visual field score than medication-first-treated eyes.

Feedback: The Laser Trial has demonstrated that laser trabeculoplasty is a safe and reasonable alternative to medication (tirnolol) in the initial treatment of open-angle glaucoma. However, 2 years later, approximately 56% of laser-first-treated eyes needed medication to adequately control pressure. Laser-first-treated-eyes had both a lower mean intraocular pressure and a higher mean visual field score after treatment than the medication-first-treated eyes. Some of the difference in visual field scores may be explained by the larger mean pupil size for the laser-first-treated eyes.

4. In an eye with increased episcleral venous pressure, which of the following medical agents would be expected to have the least intraocular pressure-lowering effect?

topical miotic (cholinergic) therapy (pilocarpine, carbachol, echothiophate iodide)

topical prostaglandin agent (latanoprost)

beta-adrenergic antagonist (betaxolol, carteolol, levobunolol, metipranolol, timolol)

topical or oral carbonic anhydrase inhibitor (acetazolamide, methazolamide, dichlorphenamide, dorzoloamide)

Feedback: Eyes with increased episcleral venous pressure to respond poorly to medications that increase trabecular outflow. Because of this, these eyes tend to respond poorly to topical miotic therapy or laser trabeculoplasty. Medical agents that reduce aqueous production (beta-adrenergic antagonists, carbonic anhydrase inhibitors) or that increase nontrabecular outflow (prostaglandins) would be expected to have a greater effect.

5. All of the following are associated with normal-tension (low-tension) glaucoma except:

disc (Drance) hemorrhages

migraine

systemic vascular disease

small optic nerve

Feedback: In normal-tension glaucoma, there is evidence of active glaucoma progression despite intraocular pressure levels that are normal or marginal. Normal-tension glaucoma is more commonly found among patients with known migraine and/or vascular disease. Drance hemorrhages, suggestive of active glaucoma progression, can be found both in high-tension and normal-tension glaucoma, but are seen more often in normal-tension glaucoma. There is a suggestion that larger optic nerves, such as those sometimes seen in high myopes, may be more susceptible to damage from elevated or marginal intraocular pressure. Small optic nerves with small cups tend to be more resistant to glaucomatous damage from elevated intraocular pressure but are more susceptible to nonarteritic ischemic optic neuropathy.

6. Important evidence of progression of primary infantile glaucoma in an infant could include each of the following except:

amblyopia

increasing myopia

increasing axial length

increasing horizontal diameter

Feedback: In glaucomas with an onset later than early childhood, the most important evidence of progression is found by examining the optic nerve and the visual field. However, in infants, uncontrolled intraocular pressure causes a diffuse enlargement of the globe manifested by increasing myopia, horizontal corneal diameter, and axial length. Amblyopia can be a substantial problem, even when infantile glaucoma is well con-trolled, due to significant anisometropia, uncorrected astigmatism, or early visual deprivation.

7. A laser peripheral iridotomy would most likely relieve angle-closure glaucoma in which of the following conditions?

iridocorneal endothelial syndrome

neovascular glaucoma

angle-closure glaucoma scleritis

pseudophakic pupillary block

Feedback: A laser peripheral iridotomy is indicated in cases with primary and secondary angle-closure glaucoma with relative or complete papillary block. This includes eyes with acute, subacute, and chronic closure glaucoma, all with a relative pupillary block, and in eyes with phakic, aphakic, or pseudophakic pupillary-block glaucoma. Angle-closure

mechanisms that operate by pulling the iris into the angle, such as occurs with neovascular glaucoma or iridocorneal endothelial syndrome, would not be expected to benefit from a laser peripheral iridotomy. During angle closure from scleritis, the peripheral iris is anteriorly displaced by rotation of the ciliary body from the thickened and edematous sclera. This mechanism of glaucoma may respond to topical cycloplegic therapy and systemic corticosteroid therapy; however, if laser therapy is needed, a peripheral iridoplasty would be more beneficial than an iridotomy.

8. Each of the following glaucomas might resolve after cataract extraction except:

phacolytic glaucoma

an eye with angle recession and phacodonesis after blunt trauma

primary angle-closure glaucoma

microspherophakia with glaucoma

Feedback: In phacolytic glaucoma, a release of proteinaceous lens material that is engulfed by macrophages clogs the trabecular meshwork and causes secondary elevation of intraocular pressure. Cataract surgery may cure this glaucoma. In microspherophakia, pupillary block is induced by the abnormal spherical shape of the lens. A laser peripheral iridotomy or removal of the lens would be expected to relieve the pupillary block. In chronic primary angle-closure glaucoma, relative pupillary block is induced by the tension of the iris sphincter muscle against the slightly anteriorly positioned lens in an eye with a relatively short axial length. Cataract surgery may improve glaucoma control or may completely eliminate glaucoma in these eyes. Cataract extraction would not be expected to improve pressure control in an eye with blunt trauma and direct trabecular damage. Angle recession may be present and is evidence of the trabecular damage. Phacodonesis is evidence of zonular disruption. In this patient, the lens is not contributing to the intraocular pressure elevation.

9. A patient with no history of glaucoma presents with a very low intraocular pressure after recent cataract surgery. The surgeon reported that the surgery was uneventful, the posterior capsule was intact, and a posterior chamber lens implant was inserted in the capsular bag. A limbal incision was constructed superiorly, 1 mm behind the anterior limbal margin, and closed with 10-0 nylon sutures. The least likely cause of a low intraocular pressure in this eye after cataract surgery would be:

inadvertent bleb formation

cyclodialysis cleft

rhegmatogenous retinal detachment

wound leak

Feedback: Low intraocular pressure after cataract surgery is not an uncommon finding. The surgeon must first search for evidence of a wound leak or rhegmatogenous retinal detachment. If neither of those two conditions is found, the next most likely reason for postoperative hypotony, in an eye with a incision, is inadvertent filtration, even in the absence of a substantial filtering bleb. Sometimes these eyes have a small diffuse area of uplifted conjunctiva with microcyst formation. A cyclodialysis cleft after cataract surgery with a limbal incision would be the least likely of the four listed options. Factors that would suggest the presence of a dialysis cleft, in addition to finding one on gonioscopy, would be a history of

traumatic surgery with capsular disruption, vitreous loss, iridodialysis, hyphema, or other evidence of difficult cataract surgery. Cyclodialysis cleft may occur after a deep scleral tunnel incision.

10. Which of following would be at greatest risk for delayed choroidal hemorrhage after glaucoma filtering surgery?

an aphakic eye with a concurrent or previous vitrectomy

an elderly patient

a phakic eye after a mitomycin C trabeculectomy

a highly myopic eye

Feedback: Ocular increases risk of a delayed suprachoroidal hemorrhage after glaucoma filtering surgery. However, two of the greatest risk factors for delayed suprachoroidal hemorrhage after glaucoma filtering surgery are surgical aphakia and a history of previous or concurrent operative vitrectomy. Absence of lens and vitreous have been hypothesized to increase the risk of development and expansion of choroidal hemorrhage. A phakic eye with hypotony after a mitomycin C trabeculectomy would be at risk for development of effusions and/or hypotony maculopathy. The risk of choroidal hemorrhage in this patient would be less than in a patient with an aphakic, vitrectomized eye. Elderly patients may be more likely to develop choroidal hemorrhage than younger patients, and highly myopic patients more likely than emmetropic patients. However, aphakia and previous or intraoperative vitrectomy are more significant risk factors.

GLAUCOMA 3

1. Medical management of glaucoma associated with inflammatory ocular disease (uveitis) and active intraocular inflammation could include all of the following except:

pilocarpine

beta blocker

cholinergic antagonist (cycloplegic agent)

topical corticosteroid

Feedback: In a patient with active intraocular inflammation, topical corticosteroid and cycloplegic therapy is appropriate. A topical beta blocker will help reduce intraocular pressure by decreasing aqueous production. Pilocarpine should not be used because it will increase pain and inflammation and may lead to posterior synechiae formation and a poorly dilating pupil, which could progress to pupillary-block glaucoma.

2. Which of the following would be the weakest indication for a combined cataract extraction and trabeculectomy in a patient with glaucoma and a visually significant cataract?

an eye with a previous history of acute angle-closure glaucoma, treated with laser iridotomy, and now with an intraocular pressure of 17 mm Hg on no medication and with no peripheral anterior synechiae

well-controlled glaucoma (intraocular pressure 13 mmHg) on a topical beta blocker and miotic agent, and oral carbonic anhydrase inhibitor

an eye with previous trabeculectomy and with intraocular pressure of 18 mmHg on a beta blocker and miotic

glaucoma controlled with one medication in an eye with advanced glaucomatous visual field loss

Feedback: A combined cataract extraction with trabeculectomy can be performed in an eye with well-controlled glaucoma on multiple antiglaucoma medications. A combined procedure is also advantageous for the patient with advanced glaucomatous visual loss, who might suffer further visual loss, including loss of fixation, in the immediate postcataract surgical period if there is substantial intraocular pressure elevation. Even in the eye with a previous trabeculectomy, a combined procedure can be helpful if the filter's function is not particularly good or not expected to survive cataract surgery. The patient with normal intraocular pressure on no medication and without substantial peripheral anterior synechiae after an episode of acute angle-closure glaucoma would be the least likely of this group to require a combined procedure.

3. The weakest indication for antifibrotic therapy in conjunction with glaucoma filtering surgery would be:

previously failed glaucoma filtering surgery

neovascular glaucoma

primary trabeculectomy and exfoliation syndrome (pseudoexfoliation) glaucoma

glaucoma in pseudophakia

Feedback: The Fluorouracil Filtering Surgery Study (FFSS) demonstrated the value of postoperative subconjunctival 5-fluorouracil in patients undergoing trabeculectomy after previously failed glaucoma filtering surgery and in aphakic or pseudophakic eyes. A number of nonrandomized reports have suggested that 5-fluorouracil also may be beneficial in eyes with neovascular glaucoma. However, filtering surgery with antifibrotic therapy has little chance of success in an eye with neovascular glaucoma unless panretinal laser photocoagulation has been performed and there has been at least some regression of the iris neovascularization. Intraoperative mitornycin-C is an alternative to 5-fluorouracil. Eyes with exfoliation syndrome glaucoma are typically not at a higher risk for failure after primary glaucoma filtering surgery.

4. A patient presents 2 years after glaucoma filtering surgery with purulent discharge and endophthalmitis. Which of the following is the most likely causative organism?

Pseudomonas aeruginosa

Staphylococcus epidermidis

Streptococcus pneumoniae

Propionibacterium acnes

Feedback: A late bleb-associated endophthalmitis tends to be caused by Streptococcus pneumoniae (pneumococcus) or Haemophilus inf!uenzae. Staphylococcus aureus and Staphylococcus epidermidis are more commonly associated with early-onset endophthalmitis after cataract surgery. Propionibacterium aenes has been assocated with a later-onset endophthalmitis after cataract surgery. Pseudomonas aeruginosa causes a fulminant endophthalmitis but is not frequently reported as a causative agent of late bleb-associated endophthalmitis.

5.The most common reason for long-term visual loss in primary infantile glaucoma is:

amblyopia

corneal edema

corneal scarring

glaucomatous optic nerve damage

Feedback: Amblyopia is the most common cause of long-term visual loss in eyes with primary infantile glaucoma. Corneal edema often resolves after a surgical procedure to reduce intraocular pressure. Breaks in Descemet's membrane and mild corneal scarring can occur but usually do not cause substantial visual loss. Serious visual loss from glaucomatous optic nerve damage can occur, but it is less common than amblyopia.

6.All of the following are commonly seen in primary infantile glaucoma except:

breaks in Descemet's membrane

myopia

increased corneal diameter

prominent, anteriorly displaced Schwalbe's line

Feedback: Elevated intraocular pressure in primary infantile glaucoma causes a generalized enlargement of the globe. This can be manifested as an increased corneal diameter, progressive myopia, and breaks in Descemet's membrane. The anterior chamber angle is usually malformed, with a high iris insertion and the appearance of a membrane-like structure over the trabecular meshwork. A prominent, anteriorly displaced Schwalbe's line, known as posterior embryotoxon, can be seen in Axenfeld-Rieger syndrome but is not typically associated with primary infantile glaucoma.

7. All of the following can cause a superior visual field defect in automated threshold perimetry except:

high false-positive rate

glaucoma

lens rim artifact

ptosis

Feedback: Glaucoma, ptosis, and lens rim artifact can cause superior visual field defects. A high false-positive rate, which indicates that the patient responded when no stimulus was presented, may be due to a nervous patient and usually causes increased thresholds rather than a visual field defect in automated threshold perimetry.

8. All of the following are risk factors for failure after glaucoma filtering surgery except:

uveitis

aphakia

iris neovascularization

pigmentary dispersion

Feedback: Aphakia, uveitis, and iris neovascularizationare risk factors for failure of standard glaucoma filtering surgery. Pigmentary dispersion alone is not a risk factor for failure. However, patients with pigmentary dispersion and pigmentary glaucoma tend to be younger, which may represent a risk factor for failure.

9. A 45-year-old black woman with a history of sarcoidosis presents with pain, decreased vision, and elevated intraocular pressure in one eye. Examination reveals 1+ cell and flare and an intraocular pressure of 32 mm Hg. She was last seen 9 days earlier with similar complaints and was placed on prednisolone acetate 1%, 4 times daily, and a topical ocular beta-adrenergic antagonist 2 times daily. She has requested another opinion. Gonioscopy demonstrates light, irregular trabecular pigmentation and a few scattered peripheral anterior synechiae, but the angle is predominantly open. The best next treatment step would be to:

add pilocarpine therapy

discontinue the topical corticosteroid

perform laser trabeculoplasty

increase the frequency of the topical corticosteroid

Feedback: In a patient with intraocular inflammatory disease (uveitis) and elevated intraocular pressure, it is essential to reduce intraocular inflammation to prevent the development of peripheral anterior synechiae, posterior synechiae, and other intraocular from inflammation. The addition of pilocarpine would not be indicated because it would increase intraocular inflammation and pain and encourage the formation of posterior and peripheral anterior synechiae. Laser trabeculoplasty is contraindicated in eyes with active intraocular inflammatory disease. It would not lower the intraocular pressure and could increase intraocular pressure, and the formation of peripheral anterior synechiae. Because there is active intraocular inflammation and because corticosteroid therapy has been used for only 2 weeks, this should not be discontinued. A corticosteroid-induced pressure elevation is unlikely at this early time, but could be considered later. The best treatment step for this patient would be to substantially increase the frequency of topical corticosteroid therapy to attempt to reduce, if not eliminate, active intraocular inflammation. This may lead to a normalization of intraocular

pressure. If the intraocular pressure is not reduced, then other antiglaucoma medical therapy can be instituted, including an oral or topical carbonic anhydrase inhibitor, apraclonidine, or brimonidine, or, if necessary, glaucoma filtering surgery can be performed.

10. Assuming equal transmission and absorption of laser energy, which time and power setting below would provide energy equal to that delivered by an argon laser with settings of 0.1 sec duration and 500 mW power?

0.02 sec; 2.5 W

0.02 sec; 1 W

1 sec; 5W

0.05 sec; 2 W

Feedback: The energy delivered by the argon laser in a "perfect" setting is determined by the power in watts or milliwatts, multiplied by the duration in seconds. The equation for this relationship is power x time = energy. If the power is increased and the time is proportionately decreased, the same amount of energy will be delivered. Answer correct abswer is the only response demonstrating that relationship in that both these parameters and those provided in the question deliver 50 millijoules of energy.

GLAUCOMA 4

1. All of the following statements are true of the topical selective beta blocker betaxolol (Betoptic) except:

It can be safely used in patients with congestive heart failure.

It is less effective in lowering intraocular pressure than levobunolol (Betagan) or timolol (Timoptic).

It has more additive effect of lowering intraocular pressure when combined with dipivefrin (Propine) than do the nonselective beta blockers.

It is safer for patients with mild, intermittent asthma attacks.

Feedback: The nonselective beta blockers levobunolol (Betagan) and timolol (Timoptic) are more effective than betaxolol (Betoptic) in lowering intraocular pressure. The relative beta-l selectivity of betaxolol allows for safer use in patients with mild, intermittent asthma. A greater additive effect of rndipivefrin (Propine) with betaxolol has been demonstrated over dipivefrin with nonselective beta blockers. Beta blockers should not be used in patients with congestive heart failure. Both beta-l selective and nonselective agents can exacerbate heart failure.

2. All of the following are associated with chronic angle-closure glaucoma with relative pupillary block except:

peripheral radial iris transillumination defects

hyperopia

cataract progression

the presence of exfoliative material in the eye

Feedback: Chronic primary angle-closure glaucoma is associated with hyperopia and cataract progression, as well as with increasing age. Although exfoliation syndrome glaucoma is usually a secondary open-angle glaucoma, there is also a clinical association of chronic angle-closure glaucoma with exfoliation syndrome. Eyes with exfoliation syndrome may have peripapillary iris transillumination defects. Peripheral radial iris transillumination defects are found in eyes with pigmentary dispersion and pigmentary glaucoma in which the anterior chamber angle is typically very deep with slight concavity of the peripheral iris. There is no clinical association of pigmentary glaucoma with chronic angle-closure glaucoma.

3. The most important finding suggestive of glaucoma in a patient with elevated intraocular pressure would be:

bilateral cup-to-disc ratio of 0.7

very deep optic cup

cup-to-disc ratio asymmetry of 0.1

cup-to-disc ratio of 0.4 with notch formation in optic nerve rim

Feedback: Although a cup-to-disc ratio asymmetry of 0.1 to 0.2 may be normal, a difference greater than 0.2 is suggestive of glaucoma. A bilateral cup-to-disc ratio of 0.7 does not necessarily indicate glaucoma. This can be seen in individuals with very large optic nerves and accompanying large optic cups. The depth of the optic cup has very little correlation with glaucoma and glaucomatous optic nerve damage. A cup-to-disc ratio of 0.4 may not arouse much suspicion for glaucoma; however, if accompanied by elevated intraocular pressure and notch formation in the optic nerve rim, it would be strongly suggestive of glaucomatous optic nerve damage.

4. All of the following are reasons for an increased mean deviation on automated threshold perimetry except:

cataract progression

glaucoma progression

topical miotic (cholinergic) therapy

high false-positive rate

Feedback: Cataract progression, the addition of topical miotic therapy, and glaucoma progression can each cause an increased mean deviation. A progression of glaucomatous defects may cause an increased mean deviation with or without an increased pattern standard deviation. A high false-positive rate, which indicates that the patient responded when no stimulus was presented, would generally not affect or would decrease the mean deviation. However, if a high false-positive rate is accompanied by supranormal thresholds, the mean deviation may be very small or positive.

5. The problem requiring the most urgent management after glaucoma filtering surgery is:

shallow anterior chamber with iris-to-cornea touch

choroidal effusion

shallow anterior chamber with lens-to-cornea touch

choroidal hemorrhage

Feedback: A shallow anterior chamber with lens-to-cornea touch requires immediate intervention. Rapid corneal decompensation and cataract progression can occur if this persists. A shallow anterior chamber with iris-to-cornea touch but without lens-to-cornea touch is a common transient finding after glaucoma filtering surgery and is usually of no consequence. Choroidal effusion is a common finding after glaucoma filtering surgery and usually resolves when intraocular pressure climbs above a hypotonous level. Drainage of choroidal effusion is seldom necessary unless it accompanies lens-to-cornea touch. A choroidal hemorrhage may require drainage; however, in most cases it can be observed or, if necessary, drained at a later time.

6. A 66-year-old man had uncontrolled intraocular pressure on glaucoma medical therapy with a previous laser peripheral iridotomy for chronic angle closure. Five days after a trabeculectomy, he has a very shallow peripheral and central anterior chamber, patent iridotomy, intraocular pressure of 40 mm Hg, and no evidence of choroidal detachment on ocular B-scan ultrasonography. All of the following may help in the management of this patient except:

vitrectomy

oral carbonic anhydrase inhibitor therapy

topical beta blocker therapy

miotic (cholinergic) therapy

Feedback: Topical beta blocker therapy and oral carbonic anhydrase inhibitor therapy can reduce intraocular pressure in eyes with aqueous misdirection (malignant glaucoma). Topical cycloplegic (anticholinergic) therapy can reduce the block in aqueous misdirection syndrome by tightening the zonules and causing a posterior displacement of the lens. Miotic (cholinergic) therapy tends to exacerbate the block and increase inflammation. Vitrectomy may be necessary if medical management is not successful.

7. Laser iridotomy is indicated in all of the following except:

chronic primary angle-closure glaucoma

inability to adequately view trabecular meshwork in an eye with narrow angle prior to performing laser trabeculoplasty

neovascular glaucoma

pseudophakic pupillary-block glaucoma

Feedback: Laser iridotomy is indicated for phakic, pseudophakic, or aphakic pupillary block and for relative pupillary block (acute angle-closure and chronic angle-closure glaucoma). If an angle has no peripheral anterior synechiae but is narrow enough to prevent performance of a laser trabeculoplasty, an iridotomy is appropriate. In neovascular glaucoma, the iris is pulled into the trabecular meshwork by fibrovascular proliferation rather than pushed into the angle by relative pupillary block. The former mechanism would not favorably respond to a laser iridotomy.

8. Two days after a trabeculectomy, a patient has an intraocular pressure of 3 mm Hg with a large bleb, no leak, and shallow but formed anterior chamber. On the third day, she presents stating that she developed moderate pain and decreased vision after bending over. The visual acuity is finger counting and the intraocular pressure is 37 mm Hg. The bleb is unchanged in appearance. There is a moderate-sized, dark, temporal choroidal detachment. The lens and vitreous are clear, and there is no evidence of a retinal detachment. All of the following are appropriate actions at this time except:

continue topical corticosteroid therapy

add cycloplegic therapy

perform drainage of choroidal hemorrhage

add topical beta blocker to reduce intraocular pressure

Feedback: After a delayed, postoperative suprachoroidal hemorrhage of limited to moderate size, it is appropriate to continue topical corticosteroid therapy and continue or add cycloplegic therapy. Analgesic therapy for pain is appropriate, and a topical beta blocker and/or oral carbonic anhydrase inhibitor can be employed to control elevated intraocular pressure. In the case described, drainage of choroidal hemorrhage would be the least appropriate action.

9. A 65-year-old man with severe proliferative diabetic retinopathy underwent a very heavy laser photocoagulation treatment session by your retinal associate 1 day previously. Today, the patient presents with mild pain, blurred vision, and an intraocular pressure of 45 mm Hg. Your retinal associate has already treated the patient with a topical beta blocker and oral carbonic anhydrase inhibitor and has referred him to you for furthermanagement of elevated intraocular pressure. The patient has no previous history of glaucoma and no evidence of iris neovascularization. On your examination, the anterior chamber appears very shallow and the fellow eye has a deep anterior chamber. What would be the most appropriate initial management step?

Perform a laser iridoplasty.

Give a topical cycloplegic agent.

Perform a trabeculectomy.

Perform a laser iridotomy.

Feedback: Very heavy panretinal laser photocoagulation can cause swelling and anterior rotation of the ciliary body, which does not respond to a laser iridotomy. The best initial step would be to administer topical cycloplegic therapy. This,

combined with a topical corticosteroid, may cause a posterior rotation and opening of the angle without additional therapy. If the angle closure fails to respond to medical therapy, then a laser iridoplasty would be the next step. Typically, this is performed with the argon laser using a low power, long duration, and large spot size. Examples of parameters are 0.2 to 0.5 sec duration, 200 to 300 mW of power, and 200 to 500 nanometer spot size. Topical cycloplegia and then laser iridoplasty would be indicated before trabeculectomy.

10. A 78-year-old man experienced unilateral sudden loss of vision 1 year previously. Currently, he complains of severe pain in that eye. Examination reveals no light-perception vision, intraocular pressure of 72 mm Hg, iris neovascularizatioll, and evidence of a central retinal vein occlusion. The least helpful therapeutic agent at this time would be:

topical cholinergic (miotic) agent

topical corticosteroid

topical beta blocker

topical cycloplegic

Feedback: The management of a painful blind eye with end-stage glaucoma can include topical cycloplegia (anticholinergic agent) and a corticosteroid agent for comfort. A topical beta blocker may provide relatively little rnintraocular pressure lowering but may provide some increased comfort. Eyes with end-stage iris neovascularization and neovascular glaucoma rnhave completely or near completely closed angles. A cholinergic agent such as pilocarpine will not successfully reduce intraocular pressure in these eyes and will often increase pain and inflammation.

GLAUCOMA 5

1. Which one of the following class of glaucoma medications lower IOP by reducing the rate of aqueous humor formation?

Carbonic anhydrase inhibitors

Miotics

Prostaglandin analogues

Hyperosmotics

Feedback: Carbonic anhydrase inhibitors decrease aqueous humor formation by inhibiting the activity of carbonic anhydrase in the ciliary epithelium. Miotics reduce IOP by increasing aqueous humor outflow through the trabecular meshwork, and prostaglandin analogues increase uveoscleral outflow of aqueous. Hyperosmotic agents draw water from the vitreous cavity by increasing blood osmolality and creating an osmotic gradient, thereby lowering IOP.

2. According to the Ocular Hypertension Treatment Study (OHTS), which one of the following is associated with an increased risk of converting from ocular hypertension to primary open-angle glaucoma?

Smaller cup-disc ratio

A history of diabetes mellitis

Decreasing age

Reduced central corneal thickness

Feedback: The Ocular Hypertension Treatment Study (OHTS) is a multicenter randomized clinical trial designed to evaluate the safety and efficacy of topical ocular hypotensive medications in preventing or delaying the development of primary open angle glaucoma in subjects with ocular hypertension. This study also identified baseline demographic and clinical features that predicted which participants were more likely to progress to primary open angle glaucoma. Enrolled patients were randomized to observation or treatment with topical glaucoma medications to lower IOP by 20% and maintain IOP less than or equal to 24 mm Hg. After 5 years of follow-up, 4.4% of treated patients developed glaucoma compared with 9.5% in the untreated observation group. Higher IOP, reduced central corneal thickness, increased cup-disc ratio, older age, and higher pattern standard deviation on visual field testing were identified as significant risk factors for the development of primary open angle glaucoma in patient with ocular hypertension. Diabetes mellitis was a negative risk factor.

3. Which one of the following was a conclusion of the Tube Versus Trabeculectomy (TVT) Study?

Tube shunt surgery produced greater IOP reduction than trabeculectomy with MMC produced.

A higher rate of postoperative complications was observed after trabeculectomy with mitomycin C (MMC) compared with tube shunt surgery.

Trabeculectomy with MMC had a higher surgical success rate than tube shunt surgery had.

Trabeculectomy with MMC was associated with a higher rate of intraoperative complications than tube shunt surgery was.

Feedback: The TVT Study is a multicenter, randomized, clinical trial comparing the safety and efficacy of tube shunt surgery and trabeculectomy with MMC in patients who had previous cataract extraction with intraocular lens implantation and/or failed filtering surgery. Enrolled patients were randomized to receive a trabeculectomy with MMC (0.4 mg/ml for 4 minutes) or 350-Baerveldt glaucoma implant. Trabeculectomy with MMC produced greater IOP reduction during the first 3 months postoperatively, but similar IOP reduction was observed thereafter. Tube shunt surgery had a higher surgical success rate than trabeculectomy with MMC. Intraoperative complications occurred at a similar rate with both surgical procedures. However, postoperative complications were more frequent after trabeculectomy with MMC compared with tube shunt surgery.

4. Alpha-2 agonists such as brimonidine (Alphagan) and apraclonidine (Iopidine) should be avoided in which type of patient?

Pseudophakic

Infants

Anemic

Asthmatics

Feedback: Alpha-2 agonists shoudl be avoided in infants because of an increased risk of respiratory depression, hypotension, and seizures. These side effects are presumably due to increased CNS penetration of the drug in children. Beta blockers should be avoided in patients with asthma, but alpha-2 agonists may be used safely. Anemia and pseudophakia are not contraindications to the use an alpha-2 agonist.

5. Which syndrome includes aniridia with cerebellar ataxia and mental retardation?

WAGR syndrome

Weyers syndrome

Lowe's syndrome

Gillespie syndrome

Feedback: Aniridia is a bilateral condition in which there is variable iris hypoplasia. Approximately 50-75% of patients with aniridia develop glaucoma. Gillespie syndrome is an autosomal recessive form of aniridia that is associated with cerebellar ataxia and mental retardation occurring in 2% of patients with aniridia. WAGR syndrome is an autosomal dominant condition seen in 13% of aniridia patients that includes Wilms tumor, aniridia, genitourinary abnormalities, and mental retardation. Lowe's syndrome and Weyers syndrome are other systemic congenital disorders that may be associated with childhood glaucoma.

6. Which one of the following is the preferred initial surgical procedure for an infant with primary congenital (infantile) glaucoma and corneal clouding?

Cyclophotocoagulation

Trabeculotomy

Trabeculectomy

Goniotomy

Feedback: Primary cogenital glaucoma is generally managed surgically, and angle surgery with goniotomy or trabeculotomy is the preferred initial approach. A goniotomy involves incising the anterior aspect of the trabecular meshwork via an ab interno approach under gonioscopic guidance. A clear cornea is required to adequately visualize the anterior chamber angle during goniotomy. In a trabeculotomy, a trabeculotome or prolene suture is inserted into Schlemm's canal from an external incision and passed into the anterior chamber. Trabeculotomy is a type of angle surgery that can be performed with or without a clear cornea. Trabeculectomy and cyclodestruction are usually used in the management of primary congenital glaucoma when angle surgery has failed.

7. Which ocular condition is associated with an increased risk of complications with cataract surgery?

Ocular hypertension

Angle recession

Pigment dispersion syndrome

Exfoliation syndrome

Feedback: Patients with exfoliation syndrome have an increased risk of complications with cataract surgery, including lens dislocation and vitreous loss. Exfoliation syndrome may be associated with zonular weakness, and phacodenesis may be identified preoperatively in some cases. Additionally, patients with this condition often dilate poorly. Pigment dispersion syndrome, ocular hypertension, and angle recession have not been reported to increase the risk of cataract extraction.

8. Which of the following drugs has been designated by the FDA to be safest during pregnancy?

Timolol (Timoptic)

Latanoprost (Xalatan)

Brimonidine (Alphagan)

Dorzolamide (Trusopt)

Feedback: Unfortunately, there is little definitive information concerning the use of glaucoma medications during pregnancy. The FDA has designated brimonidine (Alphagan) as a class B agent, and all other glaucoma agents are class C. Carbonic anhydrase inhibitors have been shown to be teratogenic in rodents, and prostaglandins increase uterine contractility. In general, it is prudent to minimize the use of glaucoma medications in pregnant women whenever possible.

9. Which one of the following is an example of a valved aqueous shunt (glaucoma drainage implant)?

Molteno implant

Schocket implant

Ahmed implant

Baerveldt implant

Feedback: Aqeous shunts are devices that are frequently used in the surgical management of glaucoma. All modern aqueous shunts share a common design consisting of a tube that is connected to an end plate. Generally the tube is inserted into the anterior chamber and shunts aqueous humor to the end plate located in the equatorial region of the globe. Valved implants incorporate a valve in their design that limits flow through the device when the IOP becomes too low (usually less than 8-10 mm Hg). The Ahmed implant is the most widely used valved implant. Nonvalved implants allow

a free flow of aqueous humor through the device. The Molteno, Baerveldt, and Schocket implants are all examples of nonvalved implants. To avoid hypotony in the early postoperative period, temporary restriction of flow is required when using nonvalved implants until fibrous encapsulation of the end plate occurs.

10. Which one of the following visual field testing strategies may allow an earlier detection of glaucoma compared with standard automated perimetry?

Confocal scanning laser ophthalmoscopy (CSLO)

Optical coherence tomography (OCT)

Suprathreshold testing

Frequency-doubling technology (FDT)

Feedback: FDT presents a low spatial frequency grating during visual-field testing that preferentially activates the M cells. Whether it is because of isolation of specific cell populations that are susceptible to early damage in glaucoma or because of the reduced redundancy allowing earlier detection of defects, FDP may allow the earlier detection of glaucoma than standard automated (white-on-white) perimetry. Suprathreshold testing presents a stimulus expected to be brighter than threshold, and is designed for screening purposes to detect moderate to severe field defects. CSLO and OCT are newer techniques to provide quantitative measurement of the optic nerve head and retinal nerve fiber layer that may aid clinicians in making an earlier diagnosis of glaucoma, but they are not visual-field testing strategies.

GLAUCOMA 6

1. All of the following statements about chronic primary angle-closure glaucoma are true except:

It can develop in a patient with primary open-angle glaucoma.

It can develop in a myopic eye.

It often causes no pain.

It can be prevented by pilocarpine therapy.

Feedback: Chronic primary angle-closure glaucoma more commonly develops in hyperopic eyes with shorter axial length and crowded eripheral anterior chamber. However, angle-closure glaucoma can develop in the myopic eye, especially one with an enlarging, progressive nuclear sclerotic cataract. Chronic angle-closure glaucoma can develop in an eye with previous primary open-angle mechanism (combined-mechanism glaucoma). Pain is uncommon in chronic angle-closure glaucoma even late in the course of the disease, when substantial intraocular pressure elevation can occur. Pilocarpine therapy usually does not relieve pupillary block. Pupillary block can be increased with miotic therapy, and further angle closure can occur.

2. Two years after a successful filtering procedure (full-thickness sclerectomy), a patient complains of pain, tearing, and blurred vision for 2 days. The visual acuity is 20/50, the intraocular pressure is 4 mm Hg, the bleb is flat, and there is a rare cell in the anterior chamber. The most likely explanation of these symptoms and signs is:

retinal detachment

endophthalmitis

bleb leak

ciliary body detachment

Feedback: The patient with a previously high, thin, ischemic bleb is more prone to develop a late bleb leak. This is usually manifested as mild discomfort, tearing, and blurred vision and may be more likely to occur after full-thickness filtering procedures or trabeculectomy with antifibrotic therapy. Objective signs include a flat bleb (usually with demonstrable leak), mildly decreased visual acuity, low intraocular pressure, and minimal or no anterior chamber inflammation. If severe anterior chamber reaction or hypopyon is seen, endophthalmitis must be suspected. Ciliary body detachment may be seen and is secondary to hypotony and inflammation in an eye with endophthalmitis, retinal detachment, or bleb leak. A retinal detachment could explain many of these findings but would be a less likely cause of this clinical picture.

3. Glaucoma-like visual field defects can be seen in all of the following conditions except:

ischernic optic neuropathy

cerebrovascular accident

retinal vascular occlusion

buried optic nerve drusen

Feedback: Buried optic nerve drusen, retinal vascular occlusion, and ischemic optic neuropathy all produce optic nerve-type visual field defects that can mimic glaucomatous visual field loss. A cerebrovascular accident would be expected to produce a postchiasmal lesion with a homonymous hemianopic or quadrantic defect.

4. A 21-year-old woman with juvenile open-angle glaucoma and 7 diopters of myopia complains of severe blurring of vision after using 1 drop of pilocarpine. The most likely cause of her symptom is:

increased hyperopia

retinal detachment

increased myopia

a small pupil

Feedback: Young, highly myopic patients may have substantially increased myopia with miotic therapy. This occurs because of a miotic-induced increased convexity of the lens and forward lens movement. All patients with a normal iris develop a small pupil on miotic therapy. This can cause nyctalopia and is more troublesome in older patients with a

cataract or other media opacity. Retinal detachment after miotic therapy can occur but would not be the most likely cause of severe visual blurring in this case.

5. A patient with elevated intraocular pressure undergoes automated static threshold perimetry. Most threshold determinations are high (40 dB to 50 dB). What is the most likely reason for this?

alert but nervous patient

drowsy patient

end-stage glaucoma

media opacity

Feedback: A drowsy patient would be expected to have a high false-negative rate (the patient fails to respond to a previously seen stimulus) and possibly also abnormally low thresholds either diffusely throughout the visual field or in an irregular pattern. Media opacity would also tend to diffusely decrease thresholds. End-stage glaucoma can produce a substantial decrease in some or all thresholded spots. An alert but nervous patient may have high thresholds accompanied by a high false-positive rate (the patient responds when no stimulus is presented).

6. A miotic agent would be least effective in a patient with glaucoma and which one of the following?

severe secondary angle closure

angle recession

aniridia with open angle

aphakia

Feedback: In the absence of substantial secondary angle closure, aniridia does not reduce the effectiveness of topical miotic (cholinergic) therapy. The effect of miotic agents is mediated through the ciliary muscle and not the pupillary sphincter, which is absent in patients with aniridia. Surgical aphakia does not alter the effectiveness of miotic therapy. Angle trauma and angle recession can decrease the effectiveness of miotic therapy. Eyes with severe synechial angle closure would be the least likely to respond to cholinergic agents and may have a paradoxical rise of intraocular pressure from miotic therapy because of a reduction of nonconventional uveoscleral outflow.

7. Which of the following statements is true of apraclonidine (Iopidine)?

It commonly causes systemic hypotension.

It is an alpha-1 adrenergic agonist.

It may cause transient lid retraction.

It is associated with macular edema in aphakic eyes.

Feedback: Apraclonidine (lopidine) can cause conjunctival blanching and lid retraction. Apraclonidine is an alpha-2 adrenergic agonist and, unlike clonidine, does not cause systemic hypotension. Epinephrine and possibly dipivefrin (Propine) are associated with macular edema in aphakic eyes.

8. Which of the following statements is true about corticosteroid-induced intraocular pressure elevation?

It is more common in patients with primary open-angle glaucoma than in patients with ocular hypertension.

Intraocular pressure usually does not return to baseline levels after discontinuing the corticosteroid.

Fluorinated corticosteroids usually cause a greater incidence of intraocular pressure elevation than nonfluorinated corticosteroid preparations.

It usually begins within 1 day after beginning corticosteroid therapy.

Feedback: Corticosteroid-induced intraocular pressure elevation usually begins about 2 to 4 weeks after initiation of corticosteroid therapy. Intraocular pressure often returns to baseline levels after discontinuation of the corticosteroid. Fluorinated corticosteroids (eg, fluorometholone) are less likely to cause intraocular pressure elevation than nonfluorinated corticosteroids. Corticosteroid responsiveness is more likely in patients with primary open-angle glaucoma than in patients with ocular hypertension or patients without intraocular pressure elevation.

9. Lens extraction may resolve glaucoma in all of the following situations except:

microspherophakia

phacolytic glaucoma

chronic primary angle-closure glaucoma

exfoliation syndrome (pseudoexfoliation) glaucoma

Feedback: Lens extraction might resolve glaucoma in microspherophakia, phacolytic glaucoma, and chronic primary angle-closure glaucoma. Exfoliation syndrome glaucoma would not be substantially improved by cataract surgery. The material is produced by nonpigmented ciliary epithelium and other ocular tissues and can be found in pseudophakic and aphakic eyes on the capsule, vitreous, corneal endothelium, iris, and anterior chamber angle.

10. Which of the following is the most helpful clue in the diagnosis of chronic primary angle-closure glaucoma?

gonioscopic findings

level of intraocular pressure at presentation

amount of glaucomatous optic nerve damage at presentation

ocular symptoms (pain, haloes)

Feedback: Patients with chronic primary angle-closure glaucoma can present with intraocular pressure that is low, normal, or elevated. Ocular symptoms may or may not be present. There may be any degree of glaucomatous optic nerve damage or no damage at all. Gonioscopic findings, preferably with the Zeiss or Posner lens, are the key to the diagnosis of chronic primary angle-closure glaucoma.

GLAUCOMA 7

1. A pars plana vitrectomy may help the treatment of glaucoma in each of the following clinical situations except:

after cataract surgery when a broken capsule leads to retained cortex and nuclear debris

ciliary-block (aqueous misdirection) glaucoma

an eye with active uveitis and vitritis

glaucoma with a chronic vitreous hemorrhage in an aphakic eye

Feedback: A pars plana vitrectomy can be beneficial in patients with glaucoma and substantial amounts of retained cortex and other lens debris after cataract surgery in which the capsule was ruptured. Lens debris can directly obstruct the trabecular meshwork or incite inflammation, which can also cause intraocular pressure elevation. If there is a chronic vitreous hemorrhage, particularly in an aphakic or pseudophakic eye, a ghost-cell glaucoma mechanism may develop. Vitrectomy map help in this situation as well. Vitrectomy may break the blockage that occurs in ciliary-block (aqueous misdirection) glaucoma. To be successful, however, there should be a disruption of the anterior vitreous face. In an eye with active intraocular inflammatory disease, topical or systemic cortico-steroid therapy may help reduce inflammation and secondarily improve intraocular pressure control. Periocular injections may cause steroid-induced glaucoma that is not easily reversed, though such an injection may be considered if it has been established that the patient is NOT a steroid responder. Typically, a vitrectomy is not recommended to improve intraocular pressure control in an eye with vitritis. However, there may be other clinical indications to perform a vitrectomy in any eye with vitiritis, such as severe vitritis, suspecited P. acnes or other infection, or ocular lymphoma.

2. A 58-year-old man presents to your office with a history of primary open-angle glaucoma and intraocular pressures of 20 mm Hg OU using a topical beta blocker twice daily and pilocarpine 4%, 3 times daily to both eyes. Gonioscopy reveals open angles and light trabecular pigmentation. You dilate the patient's pupils with two sets of tropicamide 1% and phenylephrine 2.5% drops in each eye. One hour later, you return to perform the dilated examination and the patient complains of blurred vision. There is mild corneal edema, and the intraocular pressure is 44 mm Hg bilaterally. Which of the following is the most likely reason for this acute elevation of intraocular pressure?

angle closure

reversal of intraocular pressure-lowering effect of glaucoma medication by one of the dilating agents

idiosyncratic reaction to one of the dilating agents

hypersensitivity to one of the dilating agents

Feedback: After dilation of a patient with primary open-angle glaucoma on a topical beta blocker and topical miotic agent, there can be a substantial intraocular pressure elevation, in part because of reversal of the cholinergic effect of the miotic agent. Pigment release may also contribute to intraocular pressure elevation. Hypersensitivity or an idiosyncratic reaction is unlikely. Angle closure can occur after dilation but is a less common cause of elevated intraocular pressure in this clinical situation.

3. All of the following statements are true about dipivefrin (Propine) except

It is more likely to cause contact dermatitis than a topical ocular beta adrenergic antagonist.

It is more lipophilic than topical ocular epinephrine formulations.

Systemic effects are equally likely with dipivefrin and epinephrine.

It is formulated in a lower concentration than the epinephrine formulations.

Feedback: Dipivefrin (Propine) is more lipophilic than topical ocular epinephrine and therefore penetrates the cornea better. This allows its formulation at a 0.1% strength rather than the typical formulations of epinephrine (0.5%, 1%, and 2%). Dipivefrin is a prodrug that is transformed by corneal esterases into the active agent epinephrine. Contact dermatitis is a common complication of chronic dipivefrin therapy. Dipivefrin has been shown to cause fewer cardiovascular effects than epinephrine.

4. Topical ocular beta blockers have been reported to cause all of the following side effects except:

blockage of the systemic response to hypoglycemia in diabetic patients

exacerbation of myasthenia gravis

hypokalemia

heart block

Feedback: Topical ocular beta blockers have been reported to cause heart block, exacerbation of myasthenia gravis, and blockage of the systemic response to hypoglycemia in diabetic patients. Hypokalemia is more likely to occur with oral carbonic anhydrase inhibitor therapy, especially with concurrent use of a potassium-depleting diuretic such as furosemide, hydrochlorothiazide, or chlorthalidone.

5. The topical ophthalmic prostaglandin latanoprost (Xalatan) increases nontrabecular uveoscleral outflow. One would expect which result:

latanoprost may successfully lower the pressure in an eye with elevated episcleral venous pressure

this medication would have no intraocular pressure-lowering effect in an eye with severe chronic angle closure

latanoprost's effect on intraocular pressure would be pressure dependent

little additional intraocular pressure lowering would occur in an eye already receiving topical ocular beta-adrenergic antagonist therapy

Feedback: Topical ophthalmic prostaglandin therapy increases uveoscleral outflow. Unlike trabecular outflow, nontrabecular uveoscleral outflow is not pressure dependent. Medications that increase trabecular outflow, such as pilocarpine, are not expected to have much beneficial effect on intraocular pressure in an eye with extensive angle closure; however, topical ocular prostaglandin therapy would be expected to be beneficial in such an eye. Topical beta-adrenergic antagonist therapy reduces aqueous production, and if a prostaglandin agent were coupled with this, each agent would be expected to contribute to a lowering of intraocular pressure. Topical ocular prostaglandin therapy would be expected to further lower the intraocular pressure in an eye with elevated episcleral venous pressure; this therapy may limit trabecular outflow but should not affect nontrabecular outflow. Your Pop Up Blocker Prevented a Window From Opening

6.Miotic therapy would not help and could worsen the control of intraocular pressure in each of the following except:

exfoliation syndrome glaucoma

microspherophakia

neovascular glaucoma

ciliary-block (aqueous misdirection) glaucoma

Feedback: Miotic (cholinergic) therapy includes pilocarpine, carbachol, bromide, and echothiophate iodide. These agents reduce intraocular pressure by increasing trabecular outflow. Miotic therapy can worsen ocular pressure control in ciliary-block glaucoma because ciliary body contraction loosens the lens zonules, which causes the lens to move farther forward, increasing the ciliary block. In microspherophakia, the pupillary block induced by the abnormally rounded lens can also be worsened with miotic therapy. In neovascular glaucoma, there may be substantial angle closure and little beneficial effect from miotic therapy. A cycloplegic (anticholinergic) agent, such as atropine, would be preferred in a patient with neovascular glaucoma. Exfoliation syndrome glaucoma, however, should respond well to miotic (cholinergic) therapy.

7. Topical ocular beta blockers could have a beneficial effect on all of the following disorders except

supraventricular tachyarrhythmia

angina pectoris

systemic hypertension

second-degree heart block

Feedback: Oral beta blocker therapy has been used for the control of supraventricular tachycardia and for the treatment of systemic hypertension and angina pectoris. Substantial systemic levels of beta blockers can occur with topical ocular beta blocker therapy. Topical ocular beta blocker therapy can exacerbate second-degree heart block and should be avoided in these patients.

8. Problems with apraclonidine (Iopidine) include all of the following except:

red eye

allergy

tachyphylaxis

systemic hypotension

Feedback: Apraclonidine (Iopidine), an agonist, reduces aqueous humor production. A chronic red eye may be seen with this medication, as is also seen with epinephrine and dipivefrin (Propine). An allergy to medication is not uncommon. Although apraclonidine initially has the notable short-term effect of decreasing pressure, tachyphylaxis may develop, leading to a decreased responsiveness to the medication after several weeks or months. The oral antihypertensive clonidine can cause substantial systemic hypotension. Topical apraclonidine does not cause this problem.

9. All of the following are true regarding argon laser trabeculoplasty except:

It is less effective in patients with previous blunt ocular trauma.

The effect of an argon laser trabeculoplasty tends to diminish over time.

It is effective in pigmentary glaucoma.

A repeat argon laser trabeculoplasty is about as effective as the initial procedure.

Feedback: Pigmentary glaucoma, exfoliation syndrome glaucoma, and primary open-angle glaucoma tend to have a reasonably good pressure-lowering response to argon laser trabeculoplasty. The procedure is less effective in aphakic and pseudophakic eyes and eyes with glaucoma after blunt ocular trauma. The response of argon laser trabeculoplasty tends to wear off over time, and a repeat procedure tends to be less effective.

10. Each of the following are to have a hereditary basis except:

cup/disc ratio

primary open-angle glaucoma

corticosteroid-induced pressure responsiveness

formation of an encapsulated bleb (Tenon's cyst) after trabeculectomy

Feedback: Primary open-angle is a hereditary disorder. People with this disorder are likely to demonstrate corticosteroid-induced intraocular pressure elevation. The cup/disc ratio also, in part, appears to be affected by heredity. People with a large cup/disc ratio may be more likely to sustain glaucoma damage withrnelevated intraocular pressure. The development of an encapsulated bleb (Tenon's cyst) after trabeculectomy may be associated with previous laser trabeculoplasty and previous sympathomimetic or beta-adrenergic antagonist use. No hereditary basis for the development of an encapsulated bleb has been demonstrated.

GLAUCOMA 8

1. A 60-year-old woman with proliferative diabetic retinopathy with a vitreous hemorrhage in the right eye has been followed for 2 months. She presents with severe ocular pain, and her IOP is 40 mm Hg in the right eye. Khaki-colored cells are seen in the the anterior chamber, and the angle appears open on gonioscopy. What is the most likely diagnosis?

Neovascular glaucoma

Ghost-cell glaucoma

Angle-recession glaucoma

Posner-Schlossman syndrome

Feedback: Ghost-cell glaucoma is a secondary open-angle glaucoma caused by degenerated red blood cells (ghost cells) that are less pliable than normal red blood cells and block the trabecular meshwork. Ghost cells have lost their intracellular hemoglobin and appear as small, khaki-colored cells. These cells generally develop within 1-3 months of a vitreous hemorrhage. Patients with proliferative diabetic retinopathy are at increased risk to develop neovascular glaucoma, but the angle is usually closed with this type of glaucoma. Angle-recession glaucoma and primary open angle glaucoma are chronic forms of glaucoma that are generally not associated with acute

IOP rise, and do not have khaki-colored cells in the anterior chamber.

2. Which of the following increases the risk of aqueous misdirection (malignant glaucoma)?

Chronic angle-closure glaucoma

Pseudophakia

Prior pars plana vitrectomy

High myopia

Feedback: Aqueous misdirection is a rare form of glaucoma that typically presents following ocular surgery. The condition results from a misdirection of aqueous humor posteriorly. Increased fluid volume in the vitreous cavity pushes the lens-iris diaphragm forward causing secondary angle-closure glaucoma. Axial shallowing of the anterior chamber is present in this

condition. Patients with a history of angle-closure glaucoma (acute and chronic) are at increased risk of aqueous misdirection. Prior pars plana vitrectomy does not increase the risk of this complication, and vitrectomy may actually be used to treat aqeuous misdirection that is refractory to medical and laser therapy. High myopia and pseudophakia are not risk factors for aqueous misdirection.

3. Which of the following is a feature of selective laser trabeculoplasty (SLT) compared with argon laser trabeculoplasty (ALT)?

Greater degree of IOP reduction

Less coagulative damage to the trabecular meshwork

Greater proportion of patients respond to treatment

Longer clinical experience with the procedure

Feedback: Laser trabeculoplasty is a procedure in which laser energy is delivered to the trabecular meshwork to improve the outflow of aqueous humor. ALT has been in popular use for several decades. SLT is a newer procedure that uses a frequency-doubled Nd:YAG laser. Several studies have demonstrated that the response rate and degree of IOP reduction observed after ALT and SLT are similar.

4. Which glaucoma is caused by leakage of lens protein through the capsule of a mature or hypermature cataract?

Phacomorphic glaucoma

Ectopia lentis

Phacolytic glaucoma

Lens particle glaucoma

Feedback: The protein composition of the lens changes with aging, and increased concentration of high-molecular-weight lens proteins develop over time. In a mature or hypermature lens, these proteins can be released through microscopic openings in the lens capsule. A secondary open-angle glaucoma may develop as lens proteins, phagocytizing macrophages, and other inflammatory debris obstruct the trabecular meshwork. Although medications should be used to treat the IOP elevation, definitive therapy requires cataract extraction. Lens particle glaucoma occurs when lens cortex particles obstruct the trabecular meshwork following disruption of the lens capsule with cataract extraction or ocular trauma. In phacomorphic glaucoma, a large, intumescent lens induces angle-closure glaucoma. Ectopia lentis refers to a displacement of the lens from its normal anatomic position.

5. Which variant of iridocorneal endothelial (ICE) syndrome predominantly has corneal changes with minimal iris abnormalities?

Chandler's syndrome

Axenfeld-Rieger syndrome

Cogan-Reese syndrome

Progressive iris atrophy

Feedback: Iridocorneal endothelial (ICE) syndrome is a group of disorders characterized by abnormal corneal endothelium, iris atrophy, and secondary angle-closure glaucoma. The disease is unilateral, more common in women, and usually presents between 20 and 50 years of age. Progressive iris atrophy, Chandler's syndrome, and Cogan-Reese syndrome are the 3 clinical variants that exist along a spectrum. In Chandler's syndrome, minimal iris changes are present and corneal changes predominate. Iris changes predominate in progressive iris atrophy and include progressive atrophy of the iris resulting in hole formation, corectopia, and ectropian uveae. Iris atrophy tends to be less severe in Cogan-Reese syndrome, and this condition typically has pedunculated nodules or diffuse pigmented lesions on the anterior iris surface. Axenfeld-Rieger syndrome is a congenital anomaly that is associated with iris changes that resemble ICE syndrome, but the condition is bilateral.

6. Which medication has been reported to cause secondary angle-closure glaucoma in rare cases?

Topiramate (Topamax)

Prednisone

Metoprolol (Toprol)

Azithromycin (Zithromax)

Feedback: Topiramate (Topamax) is a sulfa medication that has been reported to induce angle-closure glaucoma in rare instances. The underlying mechanism involves ciliary body congestion and development of a ciliochoroidal effusion that causes anterior rotation of the ciilary body and angle closure. Systemic corticosteroid therapy can also cause secondary glaucoma, but this occurs via an open-angle mechanism. Azithromycin and metoprolol have not been reported to cause secondary angle-closure glaucoma.

7. A 50-year-old man has recurrent episodes of markedly elevated IOP and low-grade anterior chamber inflammation. Which is the most likely diagnosis?

Glaucomatocyclitic crisis (Posner-Schlossman syndrome)

Angle-recession glaucoma

Glaucoma associated with elevated episcleral venous pressure

Exfoliation syndrome

Feedback: Glaucomatocyclitic crisis (Posner-Schlossman syndrome) is a rare type of open-angle glaucoma typically affecting middle-aged adults. It usually presents with unilateral eye pain and blurred vision associated with markedly increased IOP (40-60 mm Hg). A mild iritis is present and resolves spontaneously within a few weeks. The IOP usually

remains normal between episodes, but a chronic secondary glaucoma may develop with an increasing number of attacks. Angle-recession glaucoma, glaucoma associated with elevated episcleral venous pressure, and exfoliation glaucoma are all chronic forms of glaucoma that are not typically associated with ocular inflammation.

8. Which of the following is a characteristic sign of pigment dispersion syndrome?

Blood in Schlemm's canal

Spoke-like radial iris transillumination defects

Peripupillary atrophy

Iris bombe

Feedback: Mechanical contact between the zonular fibers and iris pigment epithelium causes iris pigment release in pigment dispersion syndrome. Spoke-like iris transillumination defects in the iris midperiphery develop from the iridozonular friction and are characteristic of this syndrome. Liberated pigment deposits on the corneal endothelium in a vertical spindle pattern (Krukenberg spindle), in the trabecular meshwork, and on the lens periphery (Scheie stripe). Peripupillary atrophy is commonly observed in exfoliation syndrome. Blood in Schlemm's canal may be seen with elevated episcleral venous pressure. Iris bombe develops in the presence of pupillary block.

9. Which syndrome involves secondary glaucoma associated with a rhegmatogenous retinal detachment?

Schwartz syndrome

Zellweger syndrome

Hallermann-Streiff syndrome

Lowe's syndrome

Feedback: Rhegmatogenous retinal detachments are typically associated with low IOP. However, Schwartz first described IOP elevation associated with a rhegmatogenous retinal detachment. The presumed mechanism of IOP elevation in Schwartz syndrome involves migration of photoreceptor outer segments through the retinal tear and into the anterior chamber, where they obstruct aqueous outflow through the trabecular meshwork. Hallermann-Streiff syndrome, Zellweger syndrome, and Lowe's syndrome are all systemic congenital disorders associated with childhood glaucomas.

10. Which of the following is a risk factor for developing primary angle-closure glaucoma (PACG)?

Male gender

Myopia

Short axial length

Young age

Feedback: Patients who develop PACG have small, crowded anterior segments and short axial lengths. The most important factors predisposing to PACG are a shallow anterior chamber, a thick lens, increased anterior curvature of the lens, a short axial length, and a small corneal diameter and radius of curvature. PACG occurs more commonly in hyperopic patients. PACG has been reported to be 2-4 times more common in women than men. The prevalence of PACG rises with increasing age.