Background and objective: Monitoring the response of retinoblastoma to globe-salvaging therapies is based on subjective assessments of changes determined by fundoscopy, ultrasound, and optical coherence tomography. Advances in organ-preserving therapies have increased the need for objective, quantitative estimates of tumor response to treatment. Primary tumor volume is a metric that can be objectively determined as a surrogate measure of treatment response.
Patients and methods: We evaluated the correlation of objective, quantitative estimates of tumor volume made with two-dimensional (2D) and three-dimensional (3D) ultrasound with gold standard pathological tumor volumes derived by analysis of enucleation specimens.
Results: Twelve eyes in 12 patients undergoing primary enucleation were evaluated by 2D and 3D ultrasound during ophthalmic examination under anesthesia prior to enucleation. 2D- and 3D-ultra-sound measurements of tumor volume were both strongly correlated with pathological estimates of tumor volume (r = 0.69, P = 0.018; and r = 0.66, P = 0.027, respectively).
Conclusions: 2D- and 3D-ultrasound measurements of retinoblastoma primary tumor volume are highly correlated with pathological estimates. 3D measurements are easy to perform with volumetric probes and consider the irregular morphology of the tumor. Further study should be undertaken to evaluate the performance of these metrics as surrogate markers of tumor response to treatment. [Ophthalmic Surg Lasers Imaging Retina 2024;55:136-140.].