3D imaging with SPACE vs 2D TSE in MR guided prostate biopsy

Transcription

1 3D imaging with SPACE vs 2D TSE in MR guided prostate biopsy Poster No.: C-2004 Congress: ECR 2011 Type: Authors: Keywords: DOI: Scientific Paper M. Garmer, S. Mateiescu, M. Busch, D. Groenemeyer; Bochum/ DE Pelvis, Oncology, Genital / Reproductive system male, MR, Image manipulation / Reconstruction, Biopsy, Imaging sequences, Neoplasia /ecr2011/C-2004 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 20

2 Purpose MR guided prostate biopsy is an up-and-coming method with good results and has been evaluated in our institute in more than 70 patients with good performance of standard 2D T2-weighted Turbospinecho sequences (2D T2w TSE) in combination with fast imaging. Localization and accuracy in biopsy of previously detected suspected lesions is limited especially at 1.5 T as the interventional procedure has to be performed without use of an endorectal coil. This reduces the image quality and results in a slightly different anatomic positioning of the prostate. A further limitation is given by the time consuming character of the procedure which excludes multiple long acquisitions with excellent image quality, time should be saved. Some lesions are small and difficult to reach, for example in an apical position (Fig:1-5: preceding diagnostic endorectal MRI of the prostate); high resolution and a good documentation are advisable. Optimized sequence strategies are essential for effective and fast performance of MR guided biopsy; 3D imaging with Sampling Perfection with Application-optimized Contrast using different flip-angle Evolutions (3D SPACE) is evaluated in this context as high resolution and the potential for reconstructions in other planes are promising. Images for this section: Page 2 of 20

3 Fig. 1: T2w TSE axial plane: small suspect lesion in the right peripheral zone Page 3 of 20

4 Fig. 2: T2w TSE koronal plane: apical position of the small suspect lesion Page 4 of 20

5 Fig. 3: ADC (apparent diffusion coefficient) map: restricted diffusion in the lesion Page 5 of 20

6 Fig. 4: T2w TSE, contrast enhanced imaging, colour coded map and conspicuous kinetic curve (red) of suspect lesion Page 6 of 20

7 Fig. 5: Chemical Shift Imaging with conspicuous spectrum in suspect lesion Page 7 of 20

8 Methods and Materials MR guided prostate biopsy was performed in a 1.5 Tesla wide bore scanner (Fig.1) using 2D and 3D imaging before and/or after puncture. All biopsy procedures started with 2D TSE (Fig.2) and/or 3D SPACE (Fig.3) T2-weighted sequences in order to localize the position of the suspected lesion(s) known from the preceding endorectal multifunctional MRI including dynamic contrast imaging, diffusionweighted sequences and 3D chemical shift imaging (spectroscopy). If the lesion was not well defined in T2-weighted images other landmarks (cysts, stones, capsula) were used. Positioning of the cylindric needle guide filled with gadolinium-chelat gel during the procedure was controlled with true fast Imaging with Steady-state Precession (truefisp) in sagittal and coronal plane (Fig.4). After biopsy the needle position was verified using 2D TSE (Fig.5) and/or 3D SPACE (Fig.6) in axial and/or coronal plane according to the location of the lesion. Reconstructions were performed in other planes as required. Fig. 7 shows a sagittal oblique reconstruction from 3D SPACE to indicate the position of the notch (green) in relation to the lesion. Pairs of 2D and 3D axial images were compared in prebiopsy and postbiopsy imaging, image quality and delineation of the suspected lesion / landmarks were rated in reconstructed images. Images for this section: Page 8 of 20

9 Fig. 1: Wide bore scanner with mounted biopsy device Page 9 of 20

10 Fig. 2: 2D T2w TSE axial plane with suspect lesion. TR/TE 4930/100, Slice 3mm TA 1:44 Page 10 of 20

11 Fig. 3: 3D SPACE axial plane with suspect lesion. TR/TE 1400/123 Slice 1.5mm, TA 3:21 Page 11 of 20

12 Fig. 4: Controlled targeting of the needle guide with sagittal and coronal truefisp (right) and axial SPACE (left) Page 12 of 20

13 Fig. 5: 2D TSE axial plane with needle tip in suspect lesion. Page 13 of 20

14 Fig. 6: 3D SPACE axial plane with needle tip in suspect lesion. Page 14 of 20

15 Fig. 7: Sagittal oblique reconstruction from axial 3D SPACE, notch (green)is located sufficiently inside the hypointense lesion; needle tip and base (red) are not capable of removing samples - histopathology: adenocarcinoma Page 15 of 20

16 Results In prebiopsy lesion detection pairs of axial 2D TSE and 3D SPACE could be compared in 27 patients. According to image quality and delineation of the suspected lesion/ landmarks 3D SPACE was found to be superior to 2D TSE in 22/27 patients with better contrast between lesion and normal prostate tissue, equal to 2D TSE in 3/27 patients and inferior to 2D TSE in 2/27 patients because of artifacts. In postbiopsy imaging pairs of axial 2D TSE and 3D SPACE could be compared in 40 specimens taken. 3D SPACE was rated superior to 2D TSE in 29/40 cores, equal to 2D TSE in 9/40 cores and inferior to 2D TSE in only 2/40 cores. 73 reconstruction sets from 3D SPACE sequences in other planes were performed; images were rated according to image quality and delineation of the suspected lesion/ landmarks and needle position; 48 were found to be excellent, 25 were rated sufficient and none was poor. Images for this section: Fig. 1: Prebiopsy lesion detection - comparison of 2D TSE and 3D SPACE Page 16 of 20

17 Fig. 2: Postbiopsy imaging - comparison of 2D TSE and 3D SPACE Page 17 of 20

18 Fig. 3: Postbiopsy imaging - Rating of images reconstructed from 3D SPACE according to image quality and delineation of the suspected lesion/landmarks and needle position Page 18 of 20

19 Conclusion 3D imaging with SPACE offers high resolution with a superior image qualitiy and lesion detection compared to 2D TSE in MR guided prostate biopsy. Sufficient good quality of reconstructed images in other planes offers exact control of needle and notch position in an acceptable time. 3D SPACE offers effective imaging in MR guided prostate biopsy. References References [1] A.B. Rosenkrantz, J. Neil, X. Kong, J. Melamed, J.S. Babb, S.S. Taneja, B. Taouli. Prostate cancer: Comparison of 3D T2-weighted with conventional 2D T2-weighted imagin for image quality and tumor detection. Am J Roentgenol. 2010; 194(2): [2] M. Garmer, M. Busch, R. Brinkmann, S. Mateiescu, B. Wagener, K. Liebenrodt, D.H.W. Groenemeyer. Magnetic Resonance guided prostate biopsy in supine position using a standard wide bore 1.5 T scanner. Oral Presentation ESMRMB 2009 congress Antalya/TR. Personal Information Marietta Garmer, MD Head of Department of Diagnostic Radiology, Groenemeyer Institute for Microtherapy, Bochum, Germany. mail to: garmer@microtherapy.de Serban Mateiescu, graduate engineer Department of Diagnostic Radiology, Groenemeyer Institute for Microtherapy, Bochum, Germany. Page 19 of 20

20 Martin Busch, PhD Head of Medical Physics, Groenemeyer Institute for Microtherapy, Bochum, Germany. Dietrich Groenemeyer, MD Chair of Radiology and Microtherapy at the University of Witten/Herdecke; Groenemeyer Institute for Microtherapy, Bochum, Germany. Page 20 of 20