Intra ocular foreign body

• Dr ali salehi

• Vitroretinal fellowship

Epidemiology

• According to the United

States Eye Injury Registry

(USEIR), the surveillance

arm of the American

Society of Ocular Trauma

(ASOT), the frequency in

the United States is 16%.

Foreign bodies

• Detection– Indirect is best method– CT next best, including plastic and glass– MRI better for organic– US supplements CT and gives info on retina– Plain films if no CT

• The most common cause

is hammering; the

incidence over time

shows a decrease at the

workplace and an

increase in the home.

International

• The frequency greatly

varies (up to 41%)

worldwide, depending

upon the population

surveyed

Mortality/Morbidity

• Most IOFBs cause

internal damage, and

most will come to rest in

the posterior segment.

Commonly injured

structures include the

cornea, the lens, and the

retina

Sex

• According to the USEIR,

93% of patients with

IOFBs are male.

Physical

• A complete examination of both eyes is necessary, including the visual acuity.

• A corneal entry wound and a hole in the iris provide trajectory information.

• The slit lamp is extremely useful in detailing all anterior segment pathologies.

• The indirect ophthalmoscope through a dilated pupil may allow direct visualization of the IOFB, which gives the most useful information for the surgeon.

• Gonioscopy and scleral depression are not recommended unless the entry wound has been surgically closed.

Causes

• Hammering and using

power tools are the most

important causes.

Protective eyewear, if

appropriate (of

polycarbonate), prevents

virtually all injuries

Imaging Studies

• CT scans are the imaging

study of choice for IOFB

localization.

– A consultation with the

CT technician is helpful

in selecting the optimal

section so as to reduce

the risk of a false-

negative result.

• Plain x-ray is useful if a

metallic IOFB is present

and a CT scan is

unavailable.

• MRI is generally not

recommended for

metallic IOFBs.

• Ultrasound is a useful

tool in localizing IOFBs,

and its careful use is

possible even if the

globe is still open;

alternatively,

intraoperative use after

wound closure can be

attempted.

Other Tests

• Electroretinography is

useful if a chronic IOFB

is found and siderosis

threatens or is present.

Medical Care• Systemic and topical

antibiotic therapy may be

started prior to the surgical

intervention.

• Topical corticosteroids are

also important to minimize

the inflammation.

• A tetanus booster may

also be appropriate.

Surgical Care

• The timing of intervention is

primarily determined by

whether the risk of

endophthalmitis is high. If the

risk is high, immediate

(emergency) surgery, for

intraocular foreign body (IOFB)

removal as well as vitrectomy if

the IOFB is in the posterior

segment, is indicated.

• In most other cases, the

surgeon has the option of

deferring intervention for

a few days to reduce the

risk of intraoperative

hemorrhage.

• The wound, however, should

be closed as soon as possible.

• A study by Zhang et al

examined 1421 eyes in 15

hospitals in China over 5

years and concluded that

closing the primary wound

within 24 hours, whether by

repair or independent self-

sealing, reduces the

endophthalmitis risk.

• If endophthalmitis

occurs, it is present at

the time of patient

presentation in over

90% of the cases.

• IOFBs in the anterior

chamber are typically

removed through a

paracentesis (not

through the original

wound) performed at 90-

180° from where the

IOFB is located.

• Viscoelastics should be

used to reduce the risk

of iatrogenic damage to

the corneal endothelium

and the lens.

• An intralenticular IOFB

does not necessarily

cause cataract.

• Unless there is a risk of

siderosis or the loss to

follow-up is high, the

IOFB and the lens may

be left in situ.

• Otherwise, usually, the

IOFB is extracted first, the

lens is extracted second,

and an intraocular lens

(IOL) is implanted

simultaneously.

• The posterior hyaloid should always be removed, and any deep impact should be prophylactically treated. For the actual removal, the best tool to extract a ferrous A posterior segment IOFB requires a vitrectomy, unless the tissue damage is minimal. IOFB is a strong intraocular magnet. For nonmagnetic IOFBs, a proper forceps may be used.

• External electromagnets

should not be used since

they do not allow

controlled extraction.

• Rarely, a scleral cut-

down is used.

• In early clinical tests, this

procedure has proven to

be very effective in the

prevention of the

development of both

proliferative

vitreoretinopathy (PVR)

and radiating retinal

folds

Medication Summary

• The goal of

pharmacotherapy is to

reduce morbidity and to

prevent complications, such

as posterior synechia

(pupillary dilation),

inflammation

(corticosteroids), and

intraocular pressure (IOP)

elevation.

Antibiotics

• For use in every case

(systemic and topical);

intravitreal usually only

if infection is present or

the case is high risk.

• Vancomycin (Vancocin,

Vancoled, Lyphocin)

• Ceftazidime (Ceptaz, Fortaz

, Tazicef, Tazidime)

First-line choice for

intravitreal gram-negative

coverage.

Third-generation

cephalosporin with broad-

spectrum, gram-negative

activity; lower efficacy

against gram-positive

organisms.

• Their mechanism of

action may involve an

alteration of RNA and

DNA metabolism or an

intracellular

accumulation of

peroxide that is toxic to

the fungal cell.

• Amphotericin B (Amphocin

, Fungizone)

• Produced by a strain of

Streptomyces nodosus; can

be fungistatic or fungicidal.

Binds to sterols, such as

ergosterol, in the fungal cell

membrane, causing

intracellular components to

leak with subsequent

fungal cell death.

Siderosis bulbi

• is a disease caused by a retained intraocular iron-containing foreign body (IOFB).

• A history of ocular trauma combined with heterochromia, mydriasis, pigmentation of the anterior chamber structures and a reduced electroretinographic response all provide an inkling of the diagnosis.

• Affected eyes can often present with a severe increase in intraocular pressure (IOP) (Talamo et al. 1985).

• A precise radiological and/or echographic localization of the IOFB, ideally supported by histological analysis of a biological sample, are vital to the confirmation of the disease. All epithelial cells defected.

Siderosis bulbi

• IRON tends to deposit in epithelial tissues– Iris - heterochromia, mid-

dilated, poorly-reactive pupil

– Lens - brown dots and cortical yellowing

– Retina -pigmentary degeneration + vesseles sclerosis

– ERG - flat within 100 days• Used to monitor

Chalcosis

• <85% pure - chalcosis,• >85% - sterile endophthalmitis (acute)• Copper deposits in basement membranes– cornea - Kayser-Fleischer ring– Iris - sluggish, greenish hue– Lens capsule - sunflower cataract– Vireous opacification– ERG like siderosis• Improves if Cu removed

Visual outcome and complications after removal of posterior segment intraocular foreign bodies through

pars plana approach• RESULTS: • Among the 50 patients, there

were 45 (90%) males and 5 (10%) females. Average age of the patients was 31.52 +9.52 (ranging from 20 to 50) years. The pre-operatively visual acuity finger counting to perception of light was 78% cases. The best corrected final visual acuity was 6/6 in 1 (2%) patient, 6/9 in 5 (10%) patients, 6/12 in 5 (10%) patients,,

• 6/18 in 3 (6%) patients, 6/24 and 6/36 in 4 (8%) patients each, 6/60 in 4 (8%) patients, finger counting in 8 (16%) patients, hand movement in 4 (8%) patients, projection of light in 9 (18%) patients and no projection of light in 3 (6%) patients. The postoperative complications were corneal opacity in 8 (16%) patients

• anterior chamber inflammatory reaction in 6 (12%)

patients, increased intraocular pressure in 1 (2%)

patient, silicone oil in anterior chamber in 1 (2%)

patient, macular scar in 7 (14%) patients, cystoid

macular edema in 1 (2%) patient, endophthalmitis

in 4 (8%) patients, retinal detachment in 11 (22%)

patients and phthisis bulbi in 3 (6%) patients.

CONCLUSION:

• Acceptable visual results were achieved after the

removal of posterior segment intraocular foreign

bodies by vitrectomy. However, multiple

complications can be encountered which require

meticulate postoperative care.

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