[home] [Personal Program] [Help]

---

Session: Poster session 2 (Odd numbers)
Session starts: Friday 27 January, 10:00
Presentation starts: 10:00

---

Sharline van Vliet - Perez (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)
Tim Crone (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)
Ruben van den Broek (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)
Robin Straathof (Delft University of Technology, Department of BioMechanical Engineering, Delft, the Netherlands)
Linda Wauben (Delft University of Technology, Department of BioMechanical Engineering, Delft, the Netherlands)
Nick van de Berg (Delft University of Technology, Department of BioMechanical Engineering, Delft, the Netherlands)
Jenny Dankelman (Delft University of Technology, Department of BioMechanical Engineering, Delft, the Netherlands)
Ben Heijmen (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)
Inger-Karine Kolkman - Deurloo (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)
Remi Nout (Erasmus MC Cancer Institute, University Medical Centre Rotterdam, Department of Radiotherapy, Rotterdam, the Netherlands)

Abstract:
Objective The currently used applicators for locally advanced cervical cancer (LACC) brachytherapy (BT) do not optimally align with individual patient anatomy and have fixed catheter positions and angles limiting treatment plan conformity. Patient-tailored applicators with optimally planned catheter channels could be the solution for this problem. To develop patient-tailored applicators, and to create a representative data set for safety tests and quality management, data on the dimensions of the distended vaginal and uterine shape is required. Little is known about the distended geometry of LACC patients after radiochemotherapy. Therefore, the aim of this study is to evaluate the vaginal and uterine geometry distended with ultrasound gel in LACC patients. Method In total 20 pre-BT MRIs of LACC patients with ultrasound gel to distend the vaginal cavity were included. The lengths and angles of the mid vagina (P0-P1), upper vagina (P1-P2), anterior cervix (P2a-P2), posterior cervix (P2-P2b), endocervical canal (P2-P3), and uterine body (P3-P4) were determined. Furthermore, the left-right (LR) widths of the vaginal cavity at height of the inferior pubic point (P0), internal ureteral ostium (P1), and external ostium (P2) were evaluated. In addition, frequency distribution maps of the vaginal cavity were made based on 3D models of the delineated MRIs. Results The lengths and angles (mean ± SD) between the vaginal and uterine segments and the LR widths were calculated. The largest variation was seen in the region P2-P4 as indicated by the length of P2-P3 (33 ± 11 mm), the width at P2 (34 ± 16 mm), the angle in P3-P4 in relation to the x-axis (123 ± 53°), and the frequency distribution maps. The mean volume of the 3D models was 48 (range: 12-69) cm3. Conclusion In this study the distended vaginal and uterine geometry was evaluated in LACC patients. The large inter-patient variation in length, angle, and width of the vaginal cavity suggests a patient-tailored applicator design, especially in the top part of the vaginal cavity. The evaluated parameters and frequency distribution maps are now available and can be used as design parameters and for safety and quality assessment of the patient-tailored applicators for LACC BT.