Purpose: Comparison of inverse optimization (IO) to modified peripheral (MP) and geometric optimization (GO) intraoperative computer planning options for permanent seed implantation (PSI) of the prostate.
Methods And Materials: One hundred ten patients underwent PSI with iodine-125. Three computer planning options were compared including MP loading, GO, and IO. Preimplant dose goals (prescribed dose [PD] of 144 Gy) and normal tissue constraints were determined at the outset by the participating physicians before intraoperative computer planning. A single computer planning system was used for this comparison. Postimplant dosimetry was performed at 4-5 weeks and compared for V(100) and D(90), urethral V(150), and rectal V(110) of the PD. Acute urinary morbidity was evaluated and compared.
Results: All three options achieved a similar preimplant median V(100) (97%). The median number of needles and seeds implanted was greater with GO (29, 75) compared to MP (16, 66) and IO (17, 66) (p<0.0001 and p=0.0024, respectively). Postimplant dosimetry showed that IO achieved a higher percentage with V(100) >95% of the PD in multivariate analysis (p=0.04) and a lower percentage postimplant D(90) <140 Gy (7%) than for MP/GO (26%) (p = 0.01). IO predicted for lower urethral dose (p=0.0169), despite a higher median D(90) (169 Gy) than either MP (159 Gy) or GO (151 Gy) (p = 0.0025). The median percentage V(150) urethra for IO was 8% vs. 16% for MP and 23% for GO (p = 0.0005). With a median followup time of 6 months, acute Grade 2 urinary symptoms were higher with GO (81%) vs. MP (36%) and IO (53%) (p = 0.0019).
Conclusions: Dosimetric outcomes for IO compare favorably to either MP or GO when performed in real time for PSI. In contrast to GO, IO and MP demonstrated excellent correlation between the intraoperative and postoperative plans while using fewer total and interior placed needles and seeds. IO appears feasible as an alternative intraoperative planning solution for PSI.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.brachy.2007.08.001 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Multi-omics models for predicting prognosis in non-small cell lung cancer patients following chemotherapy and radiotherapy: A multi-center study.
Radiother Oncol
January 2025
School of Radiology, Shandong First Medical University and Shandong Academy of Medical Sciences, Taian, China.
Background And Purpose: Quantifying tumor heterogeneity from various dimensions is crucial for precise treatment. This study aimed to develop and validate multi-omics models based on the computed tomography images, pathological images, dose and clinical information to predict treatment response and overall survival of non-small cell lung cancer (NSCLC) patients undergoing chemotherapy and radiotherapy.
Materials And Methods: This retrospective study included 220 NSCLC patients from three centers.
Static Zygomatic Guides: Digital ZAGA Concept.
Oral Maxillofac Surg Clin North Am
January 2025
Desert Ridge Oral Surgery Institute, 20950 N Tatum Boulevard #200, Phoenix, AZ 85050, USA; Private Practice of Oral and Maxillofacial Surgery, Phoenix, AZ, USA; Banner University Medical Center, Department of Oral and Maxillofacial Surgery, University of Arizona, Phoenix, AZ, USA.
Guided zygomatic implant placement surgery has emerged as a promising solution for patients with severe maxillary bone loss, offering precise implant placement and predictable outcomes. This article provides a comprehensive review of the current state-of-the-art techniques, advantages, challenges, and future directions in guided zygomatic implant surgery.
View Article and Find Full Text PDFAutomatic medical imaging segmentation via self-supervising large-scale convolutional neural networks.
Radiother Oncol
January 2025
Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA; Department of Biomedical Engineering, Emory University and Georgia Institute of Technology Atlanta, GA 30308, USA. Electronic address:
Purpose: This study aims to develop a robust, large-scale deep learning model for medical image segmentation, leveraging self-supervised learning to overcome the limitations of supervised learning and data variability in clinical settings.
Methods And Materials: We curated a substantial multi-center CT dataset for self-supervised pre-training using masked image modeling with sparse submanifold convolution. We designed a series of Sparse Submanifold U-Nets (SS-UNets) of varying sizes and performed self-supervised pre-training.
Machine learning and statistical shape modelling for real-time prediction of stent deployment in realistic anatomies.
Comput Methods Programs Biomed
January 2025
Mines Saint-Etienne, Univ Jean Monnet, Etablissement Francais du Sang, INSERM, U 1059 Sainbiose, Centre CIS, F-42023, Saint-Etienne, France. Electronic address:
The rise in minimally invasive procedures has created a demand for efficient and reliable planning software to predict intra- and post-operative outcomes. Surrogate modelling has shown promise, but challenges remain, particularly in cardiovascular applications, due to the complexity of parametrising anatomical structures and the need for large training datasets. This study aims to apply statistical shape modelling and machine learning for predicting stent deployment in real time using patient-specific models.
View Article and Find Full Text PDFComparative effectiveness of laparoscopic versus open colectomy in colon cancer patients: a study protocol for emulating a target trial using cancer registry data.
J Cancer Res Clin Oncol
January 2025
Institute for Community Medicine, Section Epidemiology of Health Care and Community Health, University Medicine Greifswald, 17489, Greifswald, Germany.
Introduction: The objective of this study is to compare the 5 year overall survival of patients with stage I-III colon cancer treated by laparoscopic colectomy versus open colectomy.
Methods: Using Mecklenburg-Western Pomerania Cancer Registry data from 2008 to 2018, we will emulate a phase III, multicenter, open-label, two-parallel-arm hypothetical target trial in adult patients with stage I-III colon cancer who received laparoscopic or open colectomy as an elective treatment. An inverse-probability weighted Royston‒Parmar parametric survival model (RPpsm) will be used to estimate the hazard ratio of laparoscopic versus open surgery after confounding factors are balanced between the two treatment arms.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!