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aspiration into the syringe. The alternative method, vitreous needle tap, is performed
by inserting a 27 to 23 gauge needle attached to a tuberculin syringe into the vitreous

cavity through the pars plana, and slowly aspirating a similar volume of fluid vitreous.
Samples collected should be sent immediately for Gram and KOH staining. It is ideal to
inoculate the samples for culture (aerobic, anaerobic and fungal) within minutes of
obtaining them to maximize the culture yield.

c) Treatment:
i) Postoperative endophthalmitis: the main treatment is in the form of intravitreal
antibiotics since it is the best way to achieve therapeutic concentration in the eye. An
empirical treatment with broadspectum antibiotics is initiated concomitantly with the

ocular fluid biopsy or core vitrectomy. The recommended combinations of antibiotics
for empirical therapy are Vancomycin 1.0mg/0/1ml and Ceftazidime 2.25mg/0.1ml.
Amikacin 400 microgm/0.1ml can be considered in exchange for ceftazidime in beta-
lactam sensitive patients. In cases of suspected fungal endophthalmitis intravitreal
antifungal agents should be administered.

In addition to eradication of viable organisms from the eye and sterilization of the
vitreous cavity, control of intraocular inflammation is an important therapeutic goal.
Inflammation can increase even when microbes are no longer viable. Corticosteroid
administration at the appropriate time - no matter what route is chosen - is to be
administered to reduce the ocular inflammation and maintain the structural integrity
of the globe.

Immediate vitrectomy should be reserved for severe endophthalmitis with a
presenting vision of perception of light. Such cases carry a significant, threefold
improved chance of obtaining 6/12 vision in comparison to vitreous tap or biopsy
according to endophthalmitis vitrectomy study. However, the procedure is not without
risks such as vitreous haemorrhage, retinal tears and retinal detachment. Hence a

limited vitrectomy of the core of the vitreous is advocated by various investigators.
Improved viewing systems and instrumentations have enabled surgeons to perform
complete vitrectomies with claims of better visual results and fewer complications. It is
highly recommended to choose the right amount of vitreous debulking depending on
the visibility of the fundus structures and severity of the inflammation. The best way to
avoid complications is to keep intraocular pressure at a constant level during the
entire procedure, thereby preventing hypotony.

Post surgery management includes use of topical antibiotics based on the culture
sensitivity. In situations where no organisms are grown on culture, a combination of
antibiotic or a broad spectrum antibiotic should be chosen to cover both the gram

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