Clinical application of a 3D ultrasound-guided prostate biopsy system

Abstract

Objectives Prostate biopsy (Bx) has for three decades been performed in a systematic, but blind fashion using 2D ultrasound (US). Herein is described the initial clinical evaluation of a 3D Bx tracking and targeting device (Artemis, Eigen, Grass Valley, CA). Our main objective was to test accuracy of the new 3D method in men undergoing first and follow-up Bx to rule out prostate cancer (CaP). Methods & Materials Patients in the study were men ages 35-87 (66.1 +/- 9.9 yrs), scheduled for Bx to rule out CaP, who entered into an IRB-approved protocol. 218 subjects underwent conventional trans-rectal US (TRUS); the tracking system was then attached to the US probe; the prostate was scanned and a 3D reconstruction was created. All Bx sites were visualized in 3D and tracked electronically. In 11 men, a pilot study was conducted to test ability of the device to return a Bx to an original site. In 47 men, multi-parametric 3 Tesla MRI – incorporating T2-weighted images, dynamic contrast enhancement, and diffusion-weighted imaging – was performed in advance of the TRUS, allowing the stored MRI images to be fused with real-time US during biopsy. Lesions on MRI were delineated by a radiologist, assigned a grade of CaP suspicion, and fused into TRUS for biopsy targeting. Results 3D Bx tracking was completed successfully in 180/218 patients, with a success rate approaching 95% among the last 50 men. Average time for Bx with the Artemis device was 15 minutes with an additional 5 minutes for MRI fusion and Bx targeting. In the tracking study, an ability to return to prior Bx sites (n=32) within 1.2 +/- 1.1 mm S.D. was demonstrated and was independent of prostate volume or location of Bx site. In the MRI fusion study, when suspicious lesions were targeted, a 33% Bx-positivity rate was found compared to a 7% positivity rate for systematic, non-targeted Bx (19/57 cores vs. 9/124 cores, p=0.03). Conclusion Use of 3D tracking and image fusion has the potential to transform MRI into a clinical tool to aid biopsy and improve current methods for diagnosis and follow-up of CaP.

Transperineal In-Bore 3-T MR Imaging–guided Prostate Biopsy: A Prospective Clinical Observational Study

“…The AS group in our study also had a high rate (61.5% [eight of 13]) of cancers detected, and 62.5% (five of eight) of these had a Gleason pattern of 4 or higher and, thus, may not be suitable for AS. an image registration method to allow display of the earlier MR images with the real-time transrectal US images on the day of the biopsy (29)(30)(31). These all use different rigid or nonrigid algorithms to help reidentify the biopsy targets in transrectal US.…”

Future of Prostate Biopsy: Who Will Get It and How?

“…The easiest approach would be image fusion to trus picture, which is moving from development phase (Hu et al, 2010) and in some centers already represents routine practice (for example Heidelberg, Germany). Two systems are in development: transrectal ArtemisEigen, Grass Valley, CA, USA (Natarajan et al, 2011) and transperineal BiopSee -MedCom, Darmstadt, Germany (Hadaschik et al, 2011). Incidental reports show identification and confirmation of cancer in patients with previously negative ANNA C-TURS biopsy, however, at present there are no studies which would compare any of the mentioned techniques and show individual strengths and indications.…”

Fusion Target Biopsy of the Prostate Using Real-Time Ultrasound and MR Images. A Multicenter RCT on Target Biopsy Techniques in the Diagnosis of Prostate Cancer

“…Despite these results MRGB remains controversial due to impracticalities, as its low availability, required expertise and time consuming nature. An upcoming technique is MRI-TRUS fusion (MTF) targeted biopsy [28][29][30][31][32][33][34][35][36][37][38]. MTF devices utilise the high diagnostic yield of the mpMRI for prostate cancer in combination with the practicality and affordability of TRUS biopsy systems by fusing the pre-interventional MR images with real-time ultrasound images.…”

“…The mpMRI information is used 'cognitively' by the physician to target tumour suspicious areas of the prostate using TRUS without applying image fusion [39,40]. All these techniques demonstrate an increased TDR of significant prostate cancer compared to systematic TRUS biopsy [17,[25][26][27][28][29][30][31][32][33][34][35][36][39][40][41][42]. There is no consensus which technique for targeted biopsy should be preferred.…”