Utility of color Doppler imaging in patients with retinoblastoma treated by intra-arterial chemotherapy.

Background: There are no clinical parameters that predict response to intra-arterial chemotherapy (IAC), which is a first-line treatment for primary and recurrent unilateral retinoblastoma. We evaluated the utility of ophthalmic ultrasound with color Doppler imaging to predict retinoblastoma response to IAC treatment.

Methods: The medical records of 14 retinoblastoma patients (20 eyes) treated with IAC were reviewed retrospectively. Baseline clinical information and ultrasound metrics were obtained from the medical record, including tumor volume, resistive index (RI) and pulsatility index (PI) of both the central retinal artery (CRA) and tumor feeding vessel (FV). Tumor volume was recorded [from repeat assessment 3-6 weeks after initial IAC.

Results: Median baseline tumor volume was 0.40 cm³ (range, 0.01-2.3); median percent change in volume after initial IAC was 71% (range, 50%-81%). Tumors with baseline volume of <1 cm³ were associated with increased CRA RI (median, 0.73) and PI (median, 1.36) compared with larger tumors (median, CRA RI 0.60 [P = 0.04]; median, CRA PI, 1.03 [P = 0.03]) as well as higher FV RI (median, 0.72) and PI (median, 1.40) than larger tumors (median FV RI, 0.63 [P = 0.02]; median FV PI, 1.01 [P = 0.001]). None of the included Doppler parameters were significantly associated with change in tumor volume following IAC.

Conclusions: In this pilot study, we found that retinoblastoma tumor volume is correlated with various Doppler characteristics of the CRA and feeder artery. Further studies are required to elucidate potential ocular blood flow patterns that may predict response to IAC.