Retinal Optical Coherence Tomography Angiography Findings following Retinoblastoma Treatment by Chemotherapy.

Purpose: To investigate the macular microvascular changes after different kinds of chemotherapy in patients with extramacular retinoblastoma (RB).

Methods: In this study, 28 eyes of 19 patients with bilateral RB treated with intravenous systemic chemotherapy (IVSC group) and 12 eyes of 12 patients with unilateral RB treated with intra-arterial chemotherapy (IAC group) were compared with 6 normal fellow eyes of 6 patients with unilateral RB treated with IVSC (IVSC fellow eye group), and 7 normal fellow eyes of 7 unilateral RB patients treated with IAC (IAC fellow eye group), as well as 12 age-matched normal eyes. Enhanced depth imaging optical coherence tomography measurements of central macular and subfoveal choroidal thickness (CMT and SFCT) as well as optical coherence tomography angiography measurements such as retinal superficial capillary density (SCD), deep capillary density (DCD), and choriocapillaris density were documented.

Results: Images of 2 eyes in the IVSC group and 8 eyes in the IAC group were excluded from the final image analysis due to severe retinal atrophy. Overall, 26 eyes with bilateral RB treated with IVSC and 4 eyes of 4 patients with unilateral RB treated with IAC were compared with the mentioned control groups. Best-corrected visual acuity was 1.03 logMAR in the IAC patients compared to 0.46 logMAR in the IVSC group at the time of imaging. While the CMT and SFCT were lower in the IAC group in comparison with the IAC fellow eye and normal groups (P < 0.05 for all), no remarkable difference was observed between the IVSC group and the control groups based on the mentioned parameters. Although the SCD showed no significant difference between the IVSC and control groups, this parameter was significantly lower in the eyes receiving IAC relative to the corresponding fellow eye group (P = 0.042) and normal control eyes (P = 0.047). The mean DCD was considerably lower in both the treatment groups compared to the control groups (P < 0.05 for all).

Conclusion: Our study showed a substantial decrease in SCD, DCD, CMT, and choroidal thickness in the IAC group, which may explain the lower visual outcome in this group.