Volume 58, Issue 1, Pages 173-177 (July 2010) Real-Time Magnetic Resonance Imaging–Guided Focal Laser Therapy in Patients with Low-Risk Prostate Cancer  Orit Raz, Masoom A. Haider, Sean R.H. Davidson, Uri Lindner, Eugen Hlasny, Robert Weersink, Mark R. Gertner, Walter Kucharcyzk, Stuart A. McCluskey, John Trachtenberg  European Urology  Volume 58, Issue 1, Pages 173-177 (July 2010) DOI: 10.1016/j.eururo.2010.03.006 Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 1 Baseline endorectal axial T2 magnetic resonance (MR) image (axial two-dimensional; 27 slices; 3-mm slice thickness; 2:53min; field of view: 15×15cm; matrix: 256×256; number of excitations: 2; repetition time: 5525ms; echo time: 98.3ms; bandwidth: 31.25kHz; ETL: 16) from patient 1; the prostate (blue line) and tumor (orange line) in the right posterior of the prostate were traced by a radiologist (MAH). European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 2 Laser fiber inserted through the selected hole of the template, which was placed against patient’s perineum in a sterile field. European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 3 Sagittal magnetic resonance image from patient 1, with a three-dimensional view of the prostate (light blue), tumor (red), template (blue), and planned needle insertion trajectory (green) generated by the planning software. European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 4 Rapid two-dimensional sagittal (2.6s per slice) fast imaging employing steady state acquisition (FIESTA) magnetic resonance scans acquired as the catheter was inserted to follow the insertion. (a) The tip of the needle is at the edge of the prostate (light blue line); (b) the tip of the needle has reached the planned location for laser ablation at the tumor site (red line). European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 5 (a) Tissue temperature map measured by magnetic resonance thermometry (echo planar imaging with multiphase; field of view: 25×25cm; matrix 256×256; number of excitations: 1; repetition time: 545ms; echo time: 20ms; flip angle: 20°; slice thickness: 3mm) during laser ablation; (b) a map of the tissue volume exceeding the threshold damage for coagulation was superimposed on the anatomical image, with the pink line measuring the maximum diameter of the ablated tissue. European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions

Fig. 6 Magnetic resonance scan that was done 2 wk after focal laser therapy in patient 2 shows the whole prostate (light blue line); the devascularized tissue (blue line) in the left posterior base of the prostate, which represents the ablated area; and the original tumor location (red line). European Urology 2010 58, 173-177DOI: (10.1016/j.eururo.2010.03.006) Copyright © 2010 European Association of Urology Terms and Conditions