Abstract
Purpose: :
To correlate pre-operative functional data with histopathology of eyes enucleated for R-E Stage V RB.
Methods: :
Seven children (6 months to 2.8 years age) with Stage V RB (3 bilateral) had preoperative acuity assessments (Teller acuity cards) and studies of topographical retinal function by multifocal electroretinogram (mfERG) under anesthesia (VERIS fundus viewer/visual stimulator). Following enucleation (8 eyes), integrity of each retinal layer in a 10 mm-long section centered on the optic nerve was scored histologically.
Results: :
Six eyes were enucleated because of retinal detachment; 2 had dense seeding. Treatment consisted of chemo only (5 eyes), chemo followed by XRT with laser (1 eye), or primary enucleation (2 eyes). In portions of the retina that were not infiltrated by tumor, pathology revealed severe retinal atrophy (loss of all retinal layers) in 4 eyes, moderate atrophy (focal and/or partial loss of retinal layers) in 2 eyes, and mild loss of inner nuclear and ganglion cell layers and normal photoreceptors in 2 eyes. The mfERG amplitude correlated with the anatomical findings; severe retinal atrophy was associated with extinguished amplitude, moderate retinal atrophy was associated with minimally detectable waveforms, and mild retinal damage was associated with larger but subnormal responses. Moderate (n = 2) or severe (n = 1) retinal atrophy were present despite retinal reattachment. Acuities of these eyes were severely reduced (20/3000 to light perception) in 7 of 8 patients. One patient had 20/400 acuity.
Conclusions: :
In stage V RB, the amplitude of the mfERG provides an index of histopathological retinal damage. Despite treatment and successful retinal reattachment, eyes with stage V RB can show non-recordable mfERG responses and severe retinal atrophy. Behavioral assessment of acuity demonstrates severe visual loss in the affected eyes.
Keywords: retinoblastoma • electroretinography: clinical • pathology: human