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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