Background: The intra-arterial chemotherapy (IAC) is increasingly used as a first-line therapy for retinoblastoma. The IAC has proved to be relatively safe. However, many local side effects of IAC have been described.

Methods: This case report describes a local side effect presenting as proptosis and myositis with vascular access difficulty of the middle meningeal artery, in a 2-year-old male with left eye diffuse multifocal stage Vb retinoblastoma complicated with retinal detachment.

Conclusions: IAC is assured to provide as efficient results in eliminating the tumor as the systemic chemotherapy, without causing the systemic side effects. It has become an alternative to systemic chemotherapy. A better understanding of the local side effects is required.