Analysis of needle site after intravitreal injection for retinoblastoma
Reviewed by Fiona Rowe

This study analysed the needle washings from retinoblastoma (RB) eyes receiving intravitreal Melphalon to consider risk of tumour externalisation from the procedure – 280 injections to 63 eyes in 61 patients were evaluated. Unilateral RB was present in 24 patients and bilateral in 37 patients. There were 31 males and 30 females with a mean age at first injection of 37 months (5.6 to 210) and a mean of 5.3 injections (1-11) per patient. Two hundred ocular surface washings and 202 needle washings produced no malignant cells in all specimens. Ocular surface washings: squamous cells were found in 15, red blood cells in two and inflammatory cells in two. Needle washings: squamous cells were found in four. At a mean follow-up of 10.4 months (0.5-28.3), no tumour growth developed at the needle site or in the subconjunctival space. Two eyes had seed tethering to the internal injection site. There were no cases of metastatic disease or death. The authors conclude a low risk of extraocular extension following intravitreal injections. 

Cytopathological evaluation of ocular surface and needle washings following intravitreal Melphalon injections for retinoblastoma.
Francis JH, Mondesire-Crump I, Marr BP, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2016;53(2):96-8.