25rg27 10.3205/25rg27 urn:nbn:de:0183-25rg272 Meeting Abstract Grisanti Grisanti Salvatore S

Lübeck

author Wittenstein Wittenstein O. O

Department of Radiation Oncology, Christian-Albrechts University of Kiel, University Medical Center Schleswig-Holstein, Campus Kiel Saphir Radiochirurgie Zentrum Norddeutschland, Kiel

author Blanck Blanck O. O

Department of Radiation Oncology, Christian-Albrechts University of Kiel, University Medical Center Schleswig-Holstein, Campus Kiel Saphir Radiochirurgie Zentrum Norddeutschland, Kiel

author Dunst Dunst J. J

Department of Radiation Oncology, Christian-Albrechts University of Kiel, University Medical Center Schleswig-Holstein, Campus Kiel

author Huttenlocher Huttenlocher S. S

Department of Radiation Oncology, Christian-Albrechts University of Kiel, University Medical Center Schleswig-Holstein, Campus Kiel Saphir Radiochirurgie Zentrum Norddeutschland, Kiel

author Grehn Grehn M. M

Department of Radiation Oncology, Christian-Albrechts University of Kiel, University Medical Center Schleswig-Holstein, Campus Kiel Saphir Radiochirurgie Zentrum Norddeutschland, Kiel

author Busch Busch M. M

Lübeck

author Rades Rades D. D

Department of Radiation Oncology, University of Lübeck, University Medical Center Schleswig-Holstein, Campus Lübeck

author Tura Tura A. A

Lübeck

author Sonntag Sonntag S. Rebecca SR

Lübeck

author German Medical Science GMS Publishing House

Düsseldorf

610 20250613 engl This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). M0622 27 Retinologische Gesellschaft 37. Jahrestagung der Retinologischen Gesellschaft Endophthalmitis/Tumor Berlin 20250627 20250628 25rg27 TextObjectives: Accurate target definition, treatment planning and delivery increases local tumor control for radiotherapy by minimizing collateral damage. To achieve this goal for uveal melanoma (UM), tantalum fiducial markers (TFMs) were previously introduced in proton and photon beam radiotherapy. However, TFMs cause pronounced scattering effects in imaging that make the delineation of small tumors difficult. The aim of this study was to evaluate silicone fiducial markers (SFMs) for the guiding of stereotactic radiosurgery (SRS) for UM.Methods: In this retrospective interventional pilot case series, three patients with small UMs 3 mm or less in tumor thickness and ≤10 mm in largest basal diameter received silicone fiducial markers. The fiducial markers were punched out (3 mm) from conventional silicone encircling bands for buckle surgery. The markers were sutured onto the sclera at the tumor margins according to the use of TFMs. MRI and CT images were used for the localization of the tumor and the markers before robotic-guided SRS.Results: The silicone fiducial markers were punched out easily from the original band, better to handle than TFMs and easy to suture onto the sclera. They could be visualized in both MRI and CT, but were more visible in CT. In the absence of scattering effects, both the markers and thus the tumor boundaries could be clearly delineated.Conclusions: This is the first report that introduces fiducial markers intraoperatively shaped from conventional silicone encircling bands usually used for retinal detachment surgery. The SFMs allow more accurate tumor delineation, resulting in the more precise planning and administration of SRS when compared to TFMs. This simple modification has a major impact on a well- known treatment approach. 0 0 0 0