3D diagnostic imaging of retinoblastoma with a novel optical coherence tomography clinical system

Purpose : Reliable in-vivo differentiation between the vital tumor / benign masses, and side effects is the main challenge for retinoblastoma, a retinal malignancy occurring in infancy. We have started an observational clinical study using our novel swept source OCT imaging system operating at 1050nm for increased depth penetration specifically validated for pediatric retinoblastoma patients. We demonstrate that the 3D mapping of tissue structure at the improved 8-15 µm resolution of OCT enhances sensitivity for detection of vital tumor tissue in-vivo & in real time. Methods : Diagnostics, laser treatment, follow-up monitoring of treatment results, side effects, and risk of new tumors are performed in parallel with OCT imaging on 0-5 year old patients.OCT is a non-invasive optical modality that produces cross sectional images of tissue up to a depth of 2 mm. The 3D visualization is a powerful tool for assessment of various retinal abnormalities due to the layered structure, and treatment side effects: scar tissue, calcification, benign masses, retinopathy, maculopathy, and choroidopathy. Our novel imaging system with a handheld scanner is designed for children in supine position under inhalation anesthesia, and accommodates the tunable focusing range for infant patients. Results : The increased sensitivity to three-dimensional morphology of tissue is the main advantage of our imaging system, as illustrated by the patient cases. The scar from laser-treated tumor with atrophic retinal layers appears flat in the en-face image (top), while the individual cross-sections reveal an elevated fibrotic mass (bottom, orange arrow). The small choroidal blood vessels within the volume of the collapsed layers are identifiable with the three-dimensional imaging capability (blue line, top; and blue arrow, bottom).Three cases of suspect masses are compared in Fig.2. While the funduscopy raised concerns of malignancy, the OCT cross-sections show different non-threatening conditions: choroidal neovascularisation, a non-malignant disorder (top), with the other two remaining after chemotherapy - fluid-filled serous retinal detachment (middle), and benign retinoma mass with calcification (bottom). Conclusions : We demonstrate the increased real-time diagnostic sensitivity for retinoblastoma patients by imaging the 3D morphology of retina at OCT resolution