ESTRO 2025 - Abstract Book

S720

Clinical - CNS

ESTRO 2025

acetazolamide peroral medication. The enucleation-free and overall survival rates were calculated using the Kaplan Meier method. LogMAR chart was used for the measurement of visual acuity, intraocular pressure was measured by dynamic contour tonometry.

Results:

Median overall survival was 84 months. Dose of 40 Gy, 30 Gy, and 25 Gy in fraction was used in 174, 17, and 1 patient, respectively. During follow-up, 21 (11 %) enucleations were performed, 4 (2 %) in the first 6 months after radiosurgery due to acute complications, and 18 (98%) as a result of tumor progression and/or late toxicity. Median time to enucleation was not reached, 84, and 72 months for T1, T2, and T3 tumors, respectively. Tumor volume decreased from 0,54 ml (IQR 0,25-0,93) at the baseline to 0,28 ml (IQR 0,13-0,56), and 0,22 ml (IQR 0,07-0,51) 12 and after 36 months, respectively. Intraocular pressure remains stable at 15 mmHg (IQR 12-21). Visual acuity deteriorated from the 0,6 logMAR (IQR 0,25-1,3) at the baseline to 1,0 logMAR (IQR 0,5-1,9), and 1,8 logMAR (IQR 0,8 3,0) 12 and after 36 months, respectively. Conclusion: Stereotactic radiosurgery with minimally invasive retrobulbar anesthesia and akinesia is feasible with low acute toxicity. Bulbus preservation is high, however, visual acuity has deteriorated.

Keywords: uveal melanoma, radiosurgery

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Digital Poster Addition of 3D-TSE Imaging into Stereotactic Radiosurgery for Brain Metastases Prolongs Time to Next Intervention Eyub Y AKDEMIR 1 , Selin Gurdikyan 1 , Kevin J Abrams 2 , Charif Sidani 2 , Margaret C Chaneles 2 , Robert H Press 1 , D Jay Wieczorek 1 , Yongsook C Lee 1 , Ranjini Tolakanahalli 1 , Alonso N Gutierrez 1 , Yazmin Odia 3 , Michael W McDermott 4 , Minesh P Mehta 1 , Rupesh Kotecha 1 1 Radiation oncology, Miami Cancer Institute, Miami, USA. 2 Radiology, Miami Cancer Institute, Miami, USA. 3 Neuro oncology, Miami Cancer Institute, Miami, USA. 4 Neurosurgery, Miami Neuroscience Institute, Miami, USA Purpose/Objective: This study evaluates the clinical benefit of adding T1 post-contrast 3D-TSE to MPRAGE imaging in stereotactic radiosurgery (SRS) planning. While the 3D-TSE sequence improves imaging sensitivity, its impact on prolonging time to next CNS-directed intervention (NCDI) remains uncertain. Material/Methods: Patients with brain metastases (BM) imaged using either MPRAGE alone or MPRAGE and 3D-TSE, with at least one follow-up scan at least eight weeks post-treatment were included. All patients underwent SRS for BM between January 2019 and February 2024. Median times to NCDI were estimated using the Kaplan-Meier method and group comparisons made using Chi-square/Mann-Whitney U tests.