SU‐E‐T‐362: Automatic Catheter Reconstruction of Flap Applicators in HDR Surface Brachytherapy

• Published in: Medical physics (Lancaster) 2014-06, Vol.41 (6Part17), p.308-308
• Main Authors: Buzurovic, I, Devlin, P, Hansen, J, O' Farrell, D, Bhagwat, M, Friesen, S, Damato, A, Lewis, J, Cormack, R
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; ACCURACY; ALGORITHMS; ANCHORS; BRACHYTHERAPY; COMPUTER CODES; COMPUTERIZED TOMOGRAPHY; DIAGNOSIS; Dosimetry; IMAGE PROCESSING; Image reconstruction; LYMPHOMAS; MANUALS; Medical image reconstruction; PATIENTS; RADIATION DOSES; SKIN; Surface reconstruction; Surface structure; Surface treatments; Three dimensional image processing; Topology
• ISSN: 0094-2405; 2473-4209
• DOI: 10.1118/1.4888695

Purpose: Catheter reconstruction is crucial for the accurate delivery of radiation dose in HDR brachytherapy. The process becomes complicated and time‐consuming for large superficial clinical targets with a complex topology. A novel method for the automatic catheter reconstruction of flap applicators is proposed in this study. Methods: We have developed a program package capable of image manipulation, using C++class libraries of The‐Visualization‐Toolkit(VTK) software system. The workflow for automatic catheter reconstruction is: a)an anchor point is placed in 3D or in the axial view of the first slice at the tip of the first, last and middle points for the curved surface; b)similar points are placed on the last slice of the image set; c)the surface detection algorithm automatically registers the points to the images and applies the surface reconstruction filter; d)then a structured grid surface is generated through the center of the treatment catheters placed at a distance of 5mm from the patient's skin. As a result, a mesh‐style plane is generated with the reconstructed catheters placed 10mm apart. To demonstrate automatic catheter reconstruction, we used CT images of patients diagnosed with cutaneous T‐cell‐lymphoma and imaged with Freiburg‐Flap‐Applicators (Nucletron™‐Elekta, Netherlands). The coordinates for each catheter were generated and compared to the control points selected during the manual reconstruction for 16catheters and 368control point Results: The variation of the catheter tip positions between the automatically and manually reconstructed catheters was 0.17mm(SD=0.23mm). The position difference between the manually selected catheter control points and the corresponding points obtained automatically was 0.17mm in the x‐direction (SD=0.23mm), 0.13mm in the y‐direction (SD=0.22mm), and 0.14mm in the z‐direction (SD=0.24mm). Conclusion: This study shows the feasibility of the automatic catheter reconstruction of flap applicators with a high level of positioning accuracy. Implementation of this technique has potential to decrease the planning time and may improve overall quality in superficial brachytherapy.