GSOR03 Presentation Time: 12:10 PM

Purpose To report procedure time for novel MRI catheter tracking technology in patients undergoing template-based interstitial gynecologic brachytherapy implants. Materials and Methods From 2018 to 2022, gynecologic patients undergoing template-based (Syed/Neblett) interstitial brachytherapy were included in this analysis. There are two cohorts: those treated with MRI-tracking technology and a comparison cohort. All patients underwent a standard template-based interstitial procedure, which included clinical examination, procedure preparation, obturator and needle insertion, mid-procedure MR images (if any), and final MRI acquisitions used in contouring and treatment planning. Additionally, for patients consenting to the MR-guided treatment investigation, custom-built MRI-tracking stylets were inserted in the implantable catheters to visualize positioning on the mid-procedure MR images as they were implanted. The procedural workflow is illustrated in Figure 1. For the investigational patient group, data logs recorded the procedure time dedicated to needle insertion. The comparison cohort of patients treated without MRI-tracking technology was used to determine the impact to procedure time when adding novel, developmental MRI-tracking technology. Extracted from the electronic medical record, the procedure start time was indicated by anesthesia handover to the attending radiation oncologist and procedure completion was indicated by the acquisition time of the post-implant MR imaging sequence. The procedure times and needle insertion times were reported as the median and interquartile range, which were compared using a student's t-test with alpha of 0.05 indicating significance. For both cohorts, patient and treatment characteristics are reported including primary disease site and average needles inserted. Results Between 2018 to 2022, 18 patients consented to interstitial procedures guided by MRI-tracking technology. For the same period, the comparison cohort without MRI-tracking technology included 62 patients. The disease sites for the MRI-tracking patients are eight cervix, seven vaginal, and three endometrial recurrences. The average needles inserted (± standard deviation) were 13 (± 4) and 14 (± 4) for the MRI-tracking and comparison cohorts (p = 0.49), respectively. Additionally, the median (interquartile range) procedure time was 95 (70 to 119) minutes and 99 (83 to 110) minutes for the MRI-tracking and non-MRI tracking patients, respectively. No statistical difference in procedure time is observed (p = 0.55). For patients with MRI-tracking, data logs times showed a median of 28 (23 to 43) minutes, which indicates the needle insertion is approximately one third of the total procedure time and approximately 2.2 minutes per needle. In the developmental stage of MRI-tracking technology, procedural times are not observed to be different from the standard procedures. Conclusions Clinical implementation of developmental MRI-tracking stylets resulted in procedure time that did not show a difference when compared to standard procedures. This result suggests the additional overhead of incorporating developmental MRI-tracking technology in the procedure is offset by the physician's capability to more quickly complete the implant based on mid-procedure visualization of catheter implants. To report procedure time for novel MRI catheter tracking technology in patients undergoing template-based interstitial gynecologic brachytherapy implants. From 2018 to 2022, gynecologic patients undergoing template-based (Syed/Neblett) interstitial brachytherapy were included in this analysis. There are two cohorts: those treated with MRI-tracking technology and a comparison cohort. All patients underwent a standard template-based interstitial procedure, which included clinical examination, procedure preparation, obturator and needle insertion, mid-procedure MR images (if any), and final MRI acquisitions used in contouring and treatment planning. Additionally, for patients consenting to the MR-guided treatment investigation, custom-built MRI-tracking stylets were inserted in the implantable catheters to visualize positioning on the mid-procedure MR images as they were implanted. The procedural workflow is illustrated in Figure 1. For the investigational patient group, data logs recorded the procedure time dedicated to needle insertion. The comparison cohort of patients treated without MRI-tracking technology was used to determine the impact to procedure time when adding novel, developmental MRI-tracking technology. Extracted from the electronic medical record, the procedure start time was indicated by anesthesia handover to the attending radiation oncologist and procedure completion was indicated by the acquisition time of the post-implant MR imaging sequence. The procedure times and needle insertion times were reported as the median and interquartile range, which were compared using a student's t-test with alpha of 0.05 indicating significance. For both cohorts, patient and treatment characteristics are reported including primary disease site and average needles inserted. Between 2018 to 2022, 18 patients consented to interstitial procedures guided by MRI-tracking technology. For the same period, the comparison cohort without MRI-tracking technology included 62 patients. The disease sites for the MRI-tracking patients are eight cervix, seven vaginal, and three endometrial recurrences. The average needles inserted (± standard deviation) were 13 (± 4) and 14 (± 4) for the MRI-tracking and comparison cohorts (p = 0.49), respectively. Additionally, the median (interquartile range) procedure time was 95 (70 to 119) minutes and 99 (83 to 110) minutes for the MRI-tracking and non-MRI tracking patients, respectively. No statistical difference in procedure time is observed (p = 0.55). For patients with MRI-tracking, data logs times showed a median of 28 (23 to 43) minutes, which indicates the needle insertion is approximately one third of the total procedure time and approximately 2.2 minutes per needle. In the developmental stage of MRI-tracking technology, procedural times are not observed to be different from the standard procedures. Clinical implementation of developmental MRI-tracking stylets resulted in procedure time that did not show a difference when compared to standard procedures. This result suggests the additional overhead of incorporating developmental MRI-tracking technology in the procedure is offset by the physician's capability to more quickly complete the implant based on mid-procedure visualization of catheter implants.