Manufacturing and evaluation of multi-channel cylinder applicator with 3D printing technology

Abstract

Purpose: This study was designed to assess dosimetric characteristics of 3D-printed personalized multi-channel cylinder applicator (MCCA). Material and methods: UnionTech RS Pro 600 (UnionTech, Inc., Shanghai, China) 3D printer was used for manufacturing MCCA. The geometry of MCCA was designed with Fusion 360 v.2.0.5827 (Autodesk, Inc.) software. The designed file was exported to Meshmixer v.3.5 (Autodesk, Inc.) to create three-dimensional model in stereolithography (STL) file format, which is the common file format for inputting data to 3D printers. We used high-temp resin, FLHTAM02 model (Formlabs Inc., MA, USA), as material in 3D printing process. This resin model has good resistance to high temperature and compatibility with various solvents. We created a simple cubic shape phantom for dosimetric evaluation of the applicator with Gafchromic EBT3 films. Also, Monte Carlo method was applied to simulate MCCA in the same configuration as in experimental test. Results: The mean ± standard deviation (SD) difference between measured and calculated doses in treatment planning system (TPS) for all control points was 0.0860 ±0.0393 Gy, corresponding to 4.01 ±1.21%. The mean ±SD difference between doses calculated by Monte Carlo simulation and TPS for all control points was 0.0996 ±0.0471 Gy, corresponding to 4.58 ±1.05%. The mean ±SD of dose difference between film measurement and Monte Carlo simulation for all control points was 0.0136 ±0.0200 Gy, corresponding to 0.60 ±0.69%. P-value for dose difference between film measurement and TPS, Monte Carlo and TPS, and film measurement and Monte Carlo were 0.7, 0.66, and 0.95, respectively. Conclusions: Dosimetric results and mechanical accuracy of MCCA show that high-temp resin with SLA 3D printing technique can be used for producing patient-specific MCCA in brachytherapy.

The value of brachytherapy in the age of advanced external beam radiotherapy: a review of the literature in terms of dosimetry

“…The history of BT has been constantly accompanied by technological developments, and further advances are expected in the future in imaging, dose calculation algorithms, physical and biological dose optimization, new applicators, electromagnetic tracking, 3D printing and new isotopes [87][88][89]. We firmly believe that image-guided BT, supported by inverse dose planning, will compete successfully with high-tech EBRT in the coming times, and we sincerely hope that BT will survive for a long time to come, and serve as a valuable modality for cancer treatment.…”

Individualized Medicine Using 3D Printing Technology in Gynecology: A Scoping Review

“…Title and abstract screening was performed by the reviewers leaving 120 studies for assessment of full text for eligibility. Eighty-eight studies were excluded for the following reasons: models were not patient speci c (52), articles were duplicates (17), not the correct patient population (8), models were not printed (7), not in English (2), non-human models (1), and/or could not be accessed (1). In total 32 studies were included for review.…”

“…13 Our scoping review has highlighted that patient speci c 3D printed brachytherapy devices have been the most commonly studied individualized 3D printed model in gynecology in the literature to date. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] The 3D printed models produced and studied were mainly personalized vaginal brachytherapy cylinder applicators and or interstitial brachytherapy needle templates in a population of patients with gynecologic malignanies including primary vaginal cancer, locally advanced or recurrent cervical or endometrial cancer. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] In addition, some studies created 3D printed devices that could be personalized and used in combination with standardized applicators or templates.…”

Characteristics of preplan‐based three‐dimensional individual template‐guided brachytherapy compared to freehand implantation

“…Preplanning is always essential and crucial to obtain a personalized 3D guidance template that can achieve the geometric description of inserted needles as well as the anticipated dose distribution in the target volume and OARs. 16,17 Huang et al 18 designed individual printed templates based on preplanning data that included 125 I seed locations and needle pathways for low-dose-rate radiation in patients with head and neck cancers. Sethi et al 19 inversely designed and printed 3D cylindrical templates through a preplanning process used for the pure interstitial therapy of two patients with vaginal tumors.…”

“…investigated the use of a 3D‐printed template for the treatment of two patients at stage IVA with pure interstitial needles and found that the 3D‐printed template was efficient and potentially valuable for use in clinical practice. Preplanning is always essential and crucial to obtain a personalized 3D guidance template that can achieve the geometric description of inserted needles as well as the anticipated dose distribution in the target volume and OARs 16,17 . Huang et al 18 .…”