Post on 17-Jul-2019
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Ans. 1. (b) PDR
10OPTHALMOLOGY
1.Which of the given disease correctly corresponds to the given fluoresceinangiography image:
a. NPDR b. PDRc. Familial dominant drusen d. Birdshot retinopathy
Explanation:This picture shows Fundus Fluorescein Angiography (FFA) of a patients.
Features seen in this picture are
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Ans. 2. (c) Staphyloma
a. Diffuse leak along superior arcade ( red circle) suggestive of NVEb. Multiple CNP (capillary non perfusion ) areas (yellow circle) c. Multiple pin pointed leaks ( green circle) suggestive of dot and blot hemorrhage
Above all findings suggestive of PDRIn NPDR, there will be no diffuse leak as circled in red circle.
PathologicPatternsofFluorescence
Pattern Cause Example Appearance on an-giogram
Hyper fluorescence Leakage AMD (CNVM)Neovascular tissueCSCR
Hyperfluorescence in-crease with time (both intensity of dye and size of lesion)
Staining Scar
Scleral show
Amount of dye visible increasesSize of lesion stays constant
Pooling Pigment epithelial defectTumor
Dye accumulating in a fluid-filled space (well-defined border, elevation o clinical exam)
Window defect Loss of RPERPE tear Drusen
Normal fluorescence of choroid accentuated (most apparent early, fades late)
Hypo fluorescence Blockage BloodPigmentFibrous tissue
Fluorescence of dye blocked by opaque medium
Nonperfusion Vascular occlusion
Coloboma
Vessels do not fill properly Absence of tissue/vessels
AMD, age-related macular degeneration; CNVM, chorodial neovascular membrane; CSCR, central serous chorioretinopathy; RPE, retinal pigment epithelium.
2.Themost likelycauseofbulgingofcornea inapatientofacutecongestiveglaucomais?a. Keratoconus b. Descemetocelec. Staphyloma d. Decreased corneal thickness
www.aim4aiims.in74Explanation:A staphyloma is an abnormal protrusion of the uveal tissue through a weak point in the eyeball. The protrusion is generalily black in colour, due to the inner layers of the eye. It occurs due to weakening of outer layer of eye (cornea or sclera) by an inflammatory or degenerative condition. It may be of 5 types, depending on the location on the eyeball (bulbus oculi). ANTERIOR (corneal) staphyloma In the anterior segment of the eye, involving the cornea and the nearby sclera. It is an ectasia of pseudocornea ( the scar formed from organised exudates and fibrous tissue covered with epithelium) which results after sloughing of cornea with iris plastered behind, it is known as anterior staphyloma. INTERCALARY staphyloma It is the name given to the localised bulge in limbal area, lined by the root of the iris. It results due to ectasia of weak scar tissue formed at the limbus, following healing of a perforating injury or a peripheral corneal ulcer. There may be associated secondary angle closure glaucoma, may cause progression of the bulge if not treated. Defective vision occurs due to marked corneal astigmatism. Treatment consists of localised staphylectomy under heavy doses of oral steroids. CILIARY Staphyloma As the name implies, it is the bulge of weak sclera lined by ciliary body, which occurs about 2–3 mm away from the limbus. Its common causes are thinning of sclera following perforating injury, scleritis & absolute glaucoma. it is part of anterior staphyloma EQUATORIAL staphyloma On the equator of the eye (region circumferencing the largest diameter orthogonal to the visual axis). Its causes are scleritis & degeneration of sclera in pathological myopia. It occurs more commonly in the regions of sclera which are perforated by vortex veins. POSTERIOR staphyloma Posterior staphyloma beneath the optic disc (right eye) In the posterior segment of the eye, typically diagnosed at the region of the macula, deforming the eye in a way that the eye-length is extended associated with myopia (nearsightedness). It is diagnosed by ophthalmoscopy, which shows an area of retinal excavation in the region of the staphyloma.
Ciliary
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Intercalary Equatorial
Posteriorlens
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Ans.3.(d)Intraocularantibniotic
3.Apatient onpost opday 5 after cataract surgerydeveloped the followingcomplication.Treatmentincludea/e:
a. Pars plana vitrectomy b. Topical antibioticc. Intravenous antibiotic d. Intraocular antibiotic
Explanation:Signs present in this picture are,
• Diffuse congestion• Corneal edema• Hypopyon
All this signs along with recent history of cataract surgery suggestive of endophthalmitis
EndophthalmitisIt is an inflammation of the internal layers of the eye resulting from intraocular colonization of infectious agents and manifesting with an exudation into vitreous cavity.It can be exogenous or endogenous.ClassificationPost surgical endophthalmitis
a. Fulminant (<4 days) • Gram negative bacteria• Streptococci• Staphylococcus Aureus
b. Acute (5-7 days)• Staph. Epidermidis• Coagulase negative cocci
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www.aim4aiims.in76c. Chronic (>4 weeks)
1. Delayed entry• Bleb related
2. Delayed onset• P. acne• Fungi• Staph epidermidis
Symptoms and signs in endophthalmitis• Pain• Rapid diminution of vision • Absent fundus glow• Anterior chamber reaction• Pupillary membrane• Hypopyon
ConfirmationofdiagnosisAll unexpected inflammatory response following intraocular surgery should be considered endophthalmitis unless proven otherwise.
Treatment Three most important determinant in outcome following endophthalmitis are-
a. Duration b. Virulence and loadc. Pharmacokinetics and spectrum of activity1. ANTIMICROBIAL THERAPY
a. Intravitreal antibiotics in post-surgical endophthalmitisb. Intravenous antibiotics in post-surgical bacterial endophthalmitis found to be
poor intraocular penetration.c. Topical and subconjunctival antibiotic can be considered
2. ANTI-INFLAMMATORY THERAPY: ROLE OF CORTICOSTEROIDS3. PARS PLANA VITRECTOMY
Close differential of endophthalmitis in a post surgical patient is TASS (Toxic Anterior Segment Syndrome)
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Ans.4.(a)Pterygium
TASS ENDOPHTHALMITISTiming The day after sx, 12-48 hrs Usually >2 day after surgery,
commonly 4-7 daysMild to moderate pain More pain (25% no pain)
Discharge Watery PurulentLid edema No Yes
Conjunctival chemosis
No Yes
Corneal edema Limbus to limbus Localized or segmental
4. Identify the given pathology:
a. Pterygium b. Pinguiculac. Chemical injury d. Fibrodysplasia
Explanation:PINGECULA
AA. Pinguecula B. Pinguecula with calci�cation
B
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Ans. 5. (a) Myopia
C. PinguculitisC
PTERYGIUM
A. Pterygium showing cap, head and body B. Stockers line in pterygium
C. Pseudopterygium secondary to chemical burn 5. Identify the refractive error:
a. Myopia b. Hypermetropia c. Compound astigmatism d. Mixed astigmatism
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79OPTHALMOLOGYExplanation:
Myopia corrected by minus lens Hyperopia correct by plus lens
(A) Simple hyperopic astigmatism; (B), (E) simple myopic astigmatism; (C) compound hyperopic astigmatism; (D) compound myopic astigmatism; (E) mixed astigmatism
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Ans. 6. (b) Myasthenia Gravis
6.ApatientpresentedwithdroopingofrightuppereyelidasshowninimageA.ThepatientwasgivenacertaindrugafterwhichtheconditionimprovedasshowninimageB.Whichofthefollowingisthepossiblediagnosis?
BeforeDrug AfterDrug
a. Tolosa-Hunt syndrome b. Myasthenia gravisc. Trigeminal neuralgia d. Multiple sclerosis
Explanation:
The image shows the Tensilon test used for the diagnosis of Myasthenia Gravis. The Tensilon test is used to diagnose Myasthenia Gravis. Patients positive for the disease should show an improvement in muscular strength following administration of Tensilon - Edrophonium - IV. Edrophonium is a very short acting Anticholinesterase and therefore increases the effective amount of acetylcholine at the neuromuscular junction in patients with Myasthenia Gravis.
Pathogenesis of Myasthenia Gravis
Axon
MitochondriaVesicle
A Normal
Nerveterminal
Muscle
AChE
AChR
B MG
THE NEUROMUSCULAR JUNCTION
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81OPTHALMOLOGYImportant points in myasthenia gravis
1. Most sensitive test: EMG (decremental response)
2. Most specific test: Antibody against Ach Esterase antibody
3. Treatment of Myasthenic crisis: Plasmapheresis and IVIG
4. Indications for thymectomy in MG
a. Anti < 15 years and > 55 years
b. Anti MuSK positive
c. Generalized MG
OssermanclassificationofMyastheniaGravis(MG)
● Occular MG ● Generalized MG
● Bullbar weakness ● Respiratory weakness/ crisis