OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS OF DEEP CAPILLARY PLEXUS MICROISCHEMIA AFTER INTRAVENOUS CHEMOTHERAPY FOR RETINOBLASTOMA.

PURPOSE: To study changes in the foveal microvascular anatomy using optical coherence tomography angiography (OCTA) after intravenous chemotherapy (IVC) for retinoblastoma (RB).

METHODS: A retrospective comparative case-control series included 10 age-matched normal eyes with no documented ocular pathology (control), 10 fellow eyes of patients with unilateral RB treated with IVC (RB fellow), and 10 eyes with extramacular RB in patients with bilateral RB treated with IVC (RB tumor). All eyes were scanned using enhanced depth imaging optical coherence tomography and OCTA. Enhanced depth imaging optical coherence tomography measurements of central macular thickness and subfoveolar choroidal thickness as well as OCTA measurements of foveal avascular zone (FAZ) area in superficial (sFAZ) and deep (dFAZ) plexus and capillary density (CD) in the superficial (sCD) and deep (dCD) plexus were performed. Comparison among the three groups was conducted.

RESULTS: Among the three cohorts (control, RB fellow, and RB tumor), there was no difference in mean age at measurement (12, 10, and 12 years) and mean interval between last IVC and OCTA (RB fellow and RB tumor) (9, 10 years). Optical coherence tomography and OCTA revealed no significant difference in central macular thickness (all P ≥ 0.161), choroidal thickness (all P ≥ 0.066), sFAZ (all P ≥ 0.618), dFAZ (all P ≥ 0.610), and sCD (all P ≥ 0.638) comparing controls versus RB fellow, controls versus RB tumor, and RB fellow versus RB tumor. By contrast, mean dCD was significantly greater in controls (52%), compared with both RB fellow (49%, P = 0.026) and RB tumor (48%, P = 0.028) groups, but no difference was found between RB fellow and RB tumor (49% vs. 48%, P = 0.515). LogMAR visual acuity showed no difference among the three groups (all P ≥ 0.150).

CONCLUSION: At mean 10-year follow-up, slight reduction in dCD seems to occur after IVC for RB without alterations in central macular thickness, choroidal thickness, FAZ, or sCD and without visual compromise.