Page 134 - NAME OF CONDITION: REFRACTIVE ERRORS

Some of the atypical manifestations of retinoblastoma include pseudohypopyon,

spontaneous hyphema, vitreous hemorrhage, phthisis bulbi and preseptal or orbital
cellulites.

Examination: The ocular examination includes estimation of vision by age-
appropriate means, an external examination, distant direct ophthalmoscopy,
examination of the eye under good illumination and magnification, direct
ophthalmoscopy and indirect ophthalmoscopy. A child with suspected
retinoblastoma necessarily needs examination under anesthesia. The intraocular
pressure is measured and the anterior segment and fundus are examined. Direct
visualization of the tumor by an indirect ophthalmoscope is diagnostic of
retinoblastoma in over 90% of cases.

Visual acuity measurement: Visual acuity assessment in children is difficult. A 3-12
month old child can only be assessed by fixation and following responses and by
determining if one eye is preferred. A child in the age range of 12 months to 36
months can be dynamically assessed using familiar toys. An older verbal child can be

assessed by using picture chart and alphabets.
External examination

1. Regional enlargement of lymph nodes
2. Eyelid and periocular edema
3. Proptosis and displacement

Slit-lamp Biomicroscopy (Handheld slit-lamp in younger children) or Examination
under illumination and magnification
1. Conjunctival congestion, circumciliary congestion
2. Anterior extraocular extension
3. Corneal horizontal diameter and clarity

4. Depth of anterior chamber, presence of tumor hypopyon
5. Iris neovascularization
6. Cataract

Fundus Evaluation
1. Bilateral fundus examination with 360 degree scleral depression
2. Tumor location, size, morphology, vascularity
3. Extent and location of subretinal fluid, subretinal seeds and vitreous seeds

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