Abstract
Abstract: :
Purpose:1. To assess the incidence of bilateral retinoblastoma and its common clinical features. 2. To review the age and sex incidence, relationship of family history and consanguinity in bilateral retinoblastoma. 3. To find out the importance of karyotyping in genetic counselling in bilateral retinoblastoma. Methods:Prospective study of all cases of bilateral retinoblastoma who reported to Aravind Eye Hospital, Madurai, India over an eighteen month period. Patient’s, parents’, siblings’, detail history and examination was undertaken. Histopathological confirmation of diagnosis in enucleated eyes and karyotyping by peripheral blood sampling was undertaken. Results:30 cases of bilateral retinoblastoma were studied. Age range was 45 days to 4 years. The commonest age group was 1 year and less (36.7%). Male to female ratio was 3:2. On presentation there was Leucocoria in 27 eyes (45%), visual loss in 10 eyes (16.7%), squint and nystagmus in 7 (11.7%) each, glaucoma and orbital cellulites in 6 eyes (10%) each, vitreous haemorrhage and keratitis in 1 eye (1.7%) each, vitreous seeding in 18 eyes (30%) and retinal detachment in 11 eyes (18.3%). Multifocal mass lesion was seen in 8 eyes (13.3%). 3 cases had intracranial extension on CT scan. Of the 30 cases, only 2 had a positive family history, 1 with an elder sibling with bilateral retinoblastoma. 10 patients had history of consanguinity (6 first degree and 4 second). On karyotyping none showed chromosomal deletion including 13. Conclusions:The incidence of bilateral retinoblastoma was 59.4% amongst all cases of retinoblastoma seen during the study. Bilateral retinoblastoma presents with severe disease and as orbital cellulites in older children. A high incidence of consanguinity (33.3%) was present in this study. Karyotyping is not adequate inspite of bilateral disease, consanguinity and a positive family history.
Keywords: retinoblastoma • genetics • clinical (human) or epidemiologic studies: prevalence/incidence