The rapid development of artificial intelligence (AI) has gained importance, with many tools already entering our daily lives. The medical field of radiation oncology is also subject to this development, with AI entering all steps of the patient journey. In this review article, we summarize contemporary AI techniques and explore the clinical applications of AI-based automated segmentation models in radiotherapy planning, focusing on delineation of organs at risk (OARs), the gross tumor volume (GTV), and the clinical target volume (CTV). Emphasizing the need for precise and individualized plans, we review various commercial and freeware segmentation tools and also state-of-the-art approaches. Through our own findings and based on the literature, we demonstrate improved efficiency and consistency as well as time savings in different clinical scenarios. Despite challenges in clinical implementation such as domain shifts, the potential benefits for personalized treatment planning are substantial. The integration of mathematical tumor growth models and AI-based tumor detection further enhances the possibilities for refining target volumes. As advancements continue, the prospect of one-stop-shop segmentation and radiotherapy planning represents an exciting frontier in radiotherapy, potentially enabling fast treatment with enhanced precision and individualization.

Background: Soft-tissue filler injections for the treatment of facial aging can result in different skin surface effects depending on the targeted facial fat compartment and fascial plane. This work investigates the tissue response of defined amounts of soft-tissue filler material injected into superficial and deep facial fat compartments by means of the calculation of the surface-volume coefficient. Methods: Four fresh frozen cephalic specimens obtained from human donors (three female and one male; mean age, 74.96 ± 22.6 years; mean body mass index, 21.82 ± 6.3 kg/m²) were studied. The superficial and deep lateral forehead compartments, deep temporal fat pad, sub–orbicularis oculi fat compartment, and deep medial cheek fat compartment were injected with aliquots of 0.1 cc of contrast-enhanced material and scanned using three-dimensional surface imaging, resulting in a total of 226 injection and scanning procedures. Results: The sub–orbicularis oculi fat compartment revealed the highest correlation coefficient (r _p = 0.992; p < 0.001) and the highest surface-volume coefficient (0.94). The compartment with the lowest tissue response was the deep medial cheek fat compartment (r _p = 0.745; p < 0.001; surface-volume coefficient = 0.29), followed by the deep lateral forehead compartment (r _p = 0.814; p < 0.001; surface-volume coefficient = 0.68), superficial lateral forehead compartment (r _p = 0.824; p < 0.001; surface-volume coefficient = 0.74), and deep temporal fat pad (r _p = 0.947; p < 0.001; overall surface-volume coefficient = 0.64). Conclusions: These results, confirmatory in their nature to current injection strategies, provide evidence for the validity and reliability of the surface-volume coefficient. Injection procedures should be targeted in terms of facial fat compartments and fascial planes for a desired aesthetic outcome, as each fat compartment and fascial plane has unique tissue responses to injected soft-tissue fillers.

Handheld 3-dimensional surface imaging (3DSI) devices of various precision are becoming more versatile in their applications and more widely accepted by clinicians for documentation. To compare the precision of facial volumetric change measurements of three 3DSI devices in the cadaveric model: Eva® (Artec 3D Inc., Luxembourg), Sense ® (3D Systems, Rock Hill, SC, USA) and iSense® (3D Systems, Rock Hill, SC, USA). A total of 336 scanning and analysis procedures were carried out in four cephalic specimens (mean age, 77.25 ± 24.3 years; and mean BMI, 21.76 ± 6.6 kg/m ²). Two superficial and two supraperiosteal regions of interest were injected with aliquots of 0.5 cc and subsequently scanned using the three different scanners. Correlation coefficients between the injected and the measured volume were computed. The correlation coefficient for the Eva® scanner was for subcutaneous regions of interest r_p=0.935 and for the supraperiosteal regions of interest r_p=0.966, as compared to r_p=0.760 and r_p=0.364 (superficial vs. supraperiosteal) for the Sense ® and r_p=0.694 and r_p=0.382 (superficial vs. supraperiosteal) for the iSense® scanner. 3DSI devices are capable of measuring surface volume changes of the face at a level of 0.5 cc surface volume change and can thus be regarded as useful tools in the pre-interventional, intra-interventional, and post-interventional phase of a treatment. One of the three evaluated scanners provided very high correlation coefficients between the injected and the measured volume (Eva®), whereas the other evaluated 3DSI devices provided moderate (Sense®) and low (iSense®) coefficients.

Hintergrund Zur Diagnostik und Therapieevaluation des Lip- und Lymphödems werden im klinischen Alltag weiterhin Maßbandmessungen eingesetzt. Hierbei werden ausgehend von standardisierten Umfangsmessungen im Bereich der betroffenen Extremitäten deren Volumina errechnet. Andere Verfahren wie Wasserverdrängung werden nicht regelhaft eingesetzt. Ziel dieser Studie war die Erprobung eines 3D Scanners als alternatives und reproduzierbares Tool zur objektiven Erfassung der Volumina der unteren Extremität. Patienten, Material und Methoden Wir führten an 20 Probanden 3D Scans der unteren Extremitäten mit einem handelsüblichen 3D Scanner, dem Artec Eva^® durch, und errechneten das Volumen mit der dazugehörigen Software. Das Volumen der Extremitäten wurde zudem gemäß standardisierter Verfahren durch die Umfangsmethode (Konusmethode und Scheibenmethode) sowie per Wasserverdrängungstechnik bestimmt. Die Ergebnisse sowie Durchführungsdauer der drei Messmethoden wurde dokumentiert und statistisch ausgewertet. Ergebnisse Mittels 3D Volumetrie zeigten sich keine signifikanten Abweichungen zur Wasserverdrängung (p > 0,05). Die Konusmethode überschätzte signifikant das in der Wasserverdrängung und 3D Volumetrie gemessene Volumen deutlich. Die Scheibenmethode zeigte keine statistisch signifikanten Abweichungen, jedoch klinisch relevant hohe Abweichungen mit einer ausgeprägten Varianz im 95 % Konfidenzintervall. Alle Verfahren zeigten hohe positive Korrelationen zueinander. Die Wasserverdrängung zeigte sich mit dem größten zeitlichen Aufwand verbunden. Schlussfolgerung Unserer Ergebnisse nach Untersuchung von 40 unteren Extremitäten zeigen, dass durch 3D Scans und Software-basierte volumetrische Berechnung in kurzer Zeit objektive und reproduzierbare Ergebnisse erzielt werden können. Die Abweichung gegenüber dem Goldstandard Background Tape measures continue to be used for the diagnosis and evaluation of lipoedema and lymphoedema in the clinical routine. Extremity volumes are calculated based on standardised circumferential measurements. Other volume measurements such as water displacement are not applied on a regular basis. This study aimed to evaluate a 3D scanner as an alternative and reproducible tool to objectively measure the volumes of the lower extremity. Patients, materials and method We used a commercially available 3D scanner, the Artec Eva^®, to perform 3D scans of the lower extremities on 20 subjects and calculated the volume using the appropriate software. In addition, limb volume was determined with standardised methods using the circumferential method (cone method and disc method) and the water displacement technique. The results and the time taken to perform the three measurement methods were documented and statistically evaluated. Results There were no significant deviations between the results from 3D volumetry and water displacement (p > 0.05). The cone method significantly overestimated the volume measured by water displacement and 3D volumetry. The disc method revealed no statistically significant differences, but clinically relevant differences with a high variance in the 95 % confidence interval. All methods demonstrated high positive correlations with each other. Water displacement was the most timeconsuming method. Conclusion Our findings obtained from the examination of 40 lower extremities show that 3D scans and software-based volumetric calculations can achieve objective and reproducible measurements in a relatively short time. The deviation from the gold-standard method of water displacement is small. Compared with the cone and disc method, however, we observed clinically relevant deviations with a high variance. We therefore recommend the 3D scan procedure for the objective documentation of conservative and surgical treatments for lipoedema or lymphoedema and have incorporated it into our clinical routine. ^* equally contributed to paper (geteilte Letztautorenschaft)

Background: Three-dimensional Surface Imaging (3DSI) is a well-established method to objectively monitor morphological changes in the female breast in the field of plastic surgery. In contrast, in radiation oncology we are still missing effective tools, which can objectively and reproducibly assess and document adverse events in breast cancer radiotherapy within the framework of clinical studies. The aim of the present study was to apply structured-light technology as a non-invasive and objective approach for the documentation of cosmetic outcome and early effects of breast radiotherapy as a proof of principle. Methods: Weekly 3DSI images of patients receiving either conventionally fractionated radiation treatment (CF-RT) or hypofractionated radiation treatment (HF-RT) were acquired during the radiotherapy treatment and clinical follow-up. The portable Artec Eva scanner (Artec 3D Inc., Luxembourg) recorded 3D surface images for the analysis of breast volumes and changes in skin appearance. Statistical analysis compared the impact of the two different fractionation regimens and the differences between the treated and the contralateral healthy breast. Results: Overall, 38 patients and a total of 214 breast imaging sessions were analysed. Patients receiving CF-RT showed a significantly higher frequency of breast erythema compared to HF-RT (93.3% versus 34.8%, p = 0.003) during all observed imaging sessions. Moreover, we found a statistically significant (p < 0.05) volumetric increase of the treated breast of the entire cohort between baseline (379 ± 196 mL) and follow-up imaging at 3 months (437 ± 224 mL), as well as from week 3 of radiotherapy (391 ± 198 mL) to follow-up imaging. In both subgroups of patients undergoing either CF-RT or HF-RT, there was a statistically significant increase (p < 0.05) in breast volumes between baseline and 3 months follow-up. There were no statistically significant skin or volumetric changes of the untreated healthy breasts. Conclusions: This is the first study utilizing 3D structured-light technology as a non-invasive and objective approach for the documentation of patients receiving breast radiotherapy. 3DSI offers potential as a non-invasive tool to objectively and precisely monitor the female breast in a radiooncological setting, allowing clinicians to objectively distinguish outcomes of different therapy modalities.