Accuracy and variability of high-dose-rate prostate brachytherapy needle tip localization using live two-dimensional and sagittally reconstructed three-dimensional ultrasound

Authors

William Thomas Hrinivich, The University of Western Ontario
Douglas A. Hoover, The University of Western Ontario
Kathleen Surry, The University of Western Ontario
Chandima Edirisinghe, Robarts Research Institute
Vikram Velker, The University of Western Ontario
Glenn Bauman, The University of Western OntarioFollow
David D'Souza, The University of Western Ontario
Aaron Fenster, The University of Western Ontario
Eugene Wong, The University of Western Ontario

Document Type

Article

Publication Date

9-1-2017

Journal

Brachytherapy

Volume

16

Issue

5

First Page

1035

Last Page

1043

URL with Digital Object Identifier

10.1016/j.brachy.2017.06.008

Abstract

Purpose To measure the accuracy and variability of manual high-dose-rate (HDR) prostate brachytherapy (BT) needle tip localization using sagittally reconstructed three-dimensional (3D) transrectal ultrasound (TRUS) augmented with live two-dimensional (2D) sagittal TRUS. Methods and Materials Ten prostate cancer patients underwent HDR-BT during which the sagittally assisted sagittally reconstructed (SASR) segmentation technique was completed in parallel with commercially available sagittally assisted axially reconstructed (SAAR) TRUS for comparison. The SASR technique makes use of live 2D ultrasound intraoperatively and allows needle tip updates using the final 3D image in the absence of image artifacts. These updates were repeated offline twice by two separate users. Needle end-length measurements were used to calculate insertion depth errors (IDEs) for each technique. Results Images of 147 needles were analyzed. For the SASR technique, both users were confident in tip positions on the final 3D image within 3 mm for 52% of needles, so these tip positions were updated. For the remaining 48% of needles, the tip positions from the live 2D images were used. This SASR technique enabled the localization of all needles with IDEs within ±3 mm for 84% of needles and IDE range of [−6.2 mm, 5.9 mm], compared with 57% and [−8.1 mm, 7.7 mm] when using the commercially available SAAR technique. Conclusions The SASR technique mitigates the impact of 3D TRUS image artifacts on HDR-BT needle tip localization by incorporating live 2D sagittal TRUS intraoperatively and provides a statistically significant reduction in IDE variance compared with the routine SAAR technique.