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Simple Summary: The present study examined the efficacy of a transbronchial metallic coil marking method for identifying small peripheral pulmonary lesions using cone–beam CT (CBCT) in a hybrid operating room. This technique enables accurate localization and resection of deeply located lesions. The procedure involved inserting an ultrathin bronchoscope under virtual navigation, placing the coil via CBCT, and performing wedge resection through video-assisted thoracoscopic surgery under fluorescence guidance. In total, 87 patients with 90 lesions, primarily small (median size 11 mm), were included. All lesions were successfully visualized and marked, with a median distance from lesions to coils of 3.6 mm and a marking time of 23.5 min. No complications arose during the marking procedure, demonstrating that CBCT is a viable alternative for identifying peripheral lung lesions while ensuring minimally invasive treatment under general anesthesia. Background/Objectives: Computed tomography (CT)-guided transbronchial metallic coil marking is useful for identifying the locations of small peripheral pulmonary lesions. Even deeply located lesions may be accurately identified and resected with adequate margins. This method is also applicable to multiple lesions. The present study examined the efficacy of our marking method using cone-beam CT (CBCT) under general anesthesia in a hybrid operation room. Methods: In the hybrid operation room, an ultrathin bronchoscope was inserted into the objective bronchus under virtual bronchoscopic navigation, and a metallic coil was installed under CBCT guidance. The lesion was then resected with wedge resection by single- or 3-port video-assisted thoracoscopic surgery under fluorescence guidance. Eighty-seven patients with 90 lesions were treated between October 2016 and December 2022. The median lesion size was 11 mm and the median distance from the pleural surface was 8.7 mm. Lesions comprised 19 pure ground-glass nodule (GGN), 35 partly solid, and 36 solid types. Results: All lesions were visualized by CBCT, and metallic coils were installed into the objective bronchi. The median distance from lesions to coils was 3.6 mm, and the median marking time was 23.5 min. All lesions were resected with sufficient margins. In total, 57 lesions were diagnosed as primary lung cancer, 26 as metastatic lung tumors, 3 as nodular lymphoid hyperplasia, and 4 as others. There were no complications associated with the marking procedure. Conclusions: CBCT represents an alternative modality for identifying peripheral lung lesions due to its ability to visualize even small GGNs. It is a minimally invasive technique because the treatment sequence is completed under general anesthesia with the same quality as previous methods performed in a CT-equipped interventional radiology suite. [ABSTRACT FROM AUTHOR]

We describe the transition-metal-free coupling for polyfluoroalkoxy arenes using polyfluoroalkoxy borates, which serve as counterions to diaryliodonium salts and transferring mediators of polyfluoroalkoxy groups. This strategy demonstrates high functional group compatibility owing to the low nucleophilicity of the borate mediator, thus offering a practical approach for synthesizing diverse polyfluoroalkoxy arenes. [ABSTRACT FROM AUTHOR]

Background: Ionoacoustics is a promising approach to reduce the range uncertainty in proton therapy. A miniature‐sized optical hydrophone (OH) was used as a measuring device to detect weak ionoacoustic signals with a high signal‐to‐noise ratio in water. However, further development is necessary to prevent wave distortion because of nearby acoustic impedance discontinuities while detection is conducted on the patient's skin. Purpose: A prototype of the probe head attached to an OH was fabricated and the required dimensions were experimentally investigated using a 100‐MeV proton beam from a fixed‐field alternating gradient accelerator and k‐Wave simulations. The beam range of the proton in a tissue‐mimicking phantom was estimated by measuring γ‐waves and spherical ionoacoustic waves with resonant frequency (SPIRE). Methods: Four sizes of probe heads were fabricated from agar blocks for the OH. Using the prototype, the γ‐wave was detected at distal and lateral positions to the Bragg peak on the phantom surface for proton beams delivered at seven positions. For SPIRE, independent measurements were performed at distal on‐ and off‐axis positions. The range positions were estimated by solving the linear equation using the sensitive matrix for the γ‐wave and linear fitting of the correlation curve for SPIRE; they were compared with those measured using a film. Results: The first peak of the γ‐wave was undistorted with the 3 × 3 × 3‐cm3 probe head used at the on‐axis and 3‐cm off‐axis positions. The range positions estimated by the γ‐wave agreed with the film‐based range in the depth direction (the maximum deviation was 0.7 mm), although a 0.6–2.1 mm deviation was observed in the lateral direction. For SPIRE, the deviation was <1 mm for the two measurement positions. Conclusions: The attachment of a relatively small‐sized probe head allowed the OH to measure the beam range on the phantom surface. [ABSTRACT FROM AUTHOR]

Background: Organ‐at‐risk (OAR) sparing is often assessed using an overlap volume‐based parameter, defined as the ratio of the volume of OAR that overlaps the planning target volume (PTV) to the whole OAR volume. However, this conventional overlap‐based predictive parameter (COPP) does not consider the volume relationship between the PTV and OAR. Purpose: We propose a new overlap‐based predictive parameter that consider the PTV volume. The effectiveness of proposed overlap‐based predictive parameter (POPP) is evaluated compared with COPP. Methods: We defined as POPP = (overlap volume between OAR and PTV/OAR volume) × (PTV volume/OAR volume). We generated intensity modulated radiation therapy (IMRT) based on step and shoot technique, and volumetric modulated arc therapy (VMAT) plans with the Auto‐Planning module of Pinnacle3 treatment planning system (v14.0, Philips Medical Systems, Fitchburg, WI) using the American Association of Physicists in Medicine Task Group (TG119) prostate phantom. The relationship between the position and size of the prostate phantom was systematically modified to simulate various geometric arrangements. The correlation between overlap‐based predictive parameters (COPP and POPP) and dose‐volume metrics (mean dose, V70Gy, V60Gy, and V37.5 Gy for rectum and bladder) was investigated using linear regression analysis. Results: Our results indicated POPP was better than COPP in predicting intermediate‐dose metrics. The bladder results showed a trend similar to that of the rectum. The correlation coefficient of POPP was significantly greater than that of COPP in < 62 Gy (82% of the prescribed dose) region for IMRT and in < 55 Gy (73% of the prescribed dose) region for VMAT regarding the rectum (p < 0.05). Conclusions: POPP is superior to COPP for creating predictive models at an intermediate‐dose level. Because rectal bleeding and bladder toxicity can be associated with intermediate‐doses as well as high‐doses, it is important to predict dose‐volume metrics for various dose levels. POPP is a useful parameter for predicting dose‐volume metrics and assisting the generation of treatment plans. [ABSTRACT FROM AUTHOR]

The SyncTraX series enables real-time tumor-tracking radiotherapy through the real-time recognition of a fiducial marker using fluoroscopic images. In this system, the isocenter should be located within approximately 5–7.5 cm from the marker, depending on the version, owing to the limited field of view. If the marker is placed away from the tumor, the isocenter should be shifted toward the marker. This study aimed to investigate stereotactic body radiotherapy (SBRT) outcomes of primary liver tumors treated with SyncTraX in cases where the isocenter was shifted marginally or outside the planning target volume (PTV). Twelve patients with 13 liver tumors were included in the analysis. Their isocenter was shifted toward the marker and was placed marginally or outside the PTV. The prescribed doses were generally 40 Gy in four fractions or 48 Gy in eight fractions. The overall survival (OS) and local control (LC) rates were calculated using the Kaplan–Meier method. All patients completed the scheduled SBRT. The median distance between the fiducial marker and PTV centroid was 56.0 (interquartile range [IQR]: 52.7–66.7) mm. By shifting the isocenter toward the marker, the median distance between the marker and isocenter decreased to 34.0 (IQR: 33.4–39.7) mm. With a median follow-up period of 25.3 (range: 6.9–70.0) months, the 2-year OS and LC rates were 100.0% (95% confidence interval: 100–100). An isocenter shift makes SBRT with SyncTraX feasible in cases where the fiducial marker is distant from the tumor. [ABSTRACT FROM AUTHOR]