To the Editor We read with interest the article by Yousef et al.1 In their search for articles about intra-arterial chemotherapy (IAC) for retinoblastoma, they identified 208 but may have missed others as the search terms ophthalmic artery chemosurgery (OAC), intraarterial, and intra arterial were not used. One hundred ninety-eight publications (approximately 95% of the published literature on this topic) were not included in their “systematic review.” Only 12 articles were included and more than half of all these patients were from 1 publication from Japan using the balloon technique (which is rarely used today).