Multiparametric MRI Prostate Imaging Protocol November 2015 Full Acquisition Protocol with Parameters GE 3T Magnet with Software Version DV25

Transcription

1 3Plane Loc SSFSE Multiparametric MRI Prostate Imaging Protocol November 2015 Full Acquisition Protocol with Parameters GE 3T Magnet with Software Version DV25 Save Series Scan After acquisition, scroll through the slices to make sure the spine, the endorectal coil and prostate are visible on the sagittal images. If the anatomy is ambiguous, or the patient has an abnormal spinal curvature, represcribe and reacquire the scout. Check the coil positioning and adjust if necessary. 3 1/5/2016

2 Ax T1 3D Open the Scout and prescribe a 3D volume over the pelvis, extending from the aortic bifurcation to 2cm inferior to the prostate. Add a SAT band superior to the prescription box. Aortic bifurcation Save Series Scan After the Ax T1 3D images appear, check to see if the endorectal coil is centered in the S/I direction along the prostate and in the R/L direction along the posterior edge of the prostate. If not, realign endorectal coil. 4 1/5/2016

3 Ax T2 FSE Open the Scout and prescribe the maximum number of slices, covering the full prostate. This is an oblique scan, and should match the obliquity of the prostate and rectum in the sagittal view. Do not change the obliquity in R/L, on the coronal view. Obliquity matches the prostate and rectum Save Series Scan 5 1/5/2016

4 Ax Cube T2-100ETL, 2Rx Copy Rx from AX T2 FSE (to get the same obliquity), increase to 64 slices, extending the Rx superiorly Move SAT band to cover above the prescription Save Scan 6 1/5/2016

5 Ax DWI rfov b=600 Remember to scroll through each slice on the Ax T2 prescription. Because we are decreasing slices, slices may need to be repositioned to cover the prostate. DO NOT change the obliquity; it should match that of the Ax T2. Note: On some scanners, parameters in the Diffusion tab reset; check the Diffusion tab during prescription. Copy Rx from AX T2 FSE (copy only the region, uncheck all other options: slice thickness, FOV, etc) Decrease number of slices to max allowed Shift prescription in A/P if necessary to center prescription on the prostate Save Series Scan Note: If scanning a patient with brachytherapy seeds, prescribe the DWI sequence labeled (pt with seeds) at the end of the protocol. 7 1/5/2016

6 Ax DWI rfov b=1350 Copy Rx from Ax DWI b=600 (copy only the region, uncheck all other options: slice thickness, FOV, etc) Decrease number of slices to max allowed DO NOT change the obliquity; it should match the Ax T2 obliquity. Note: On some scanners, parameters in the Diffusion tab reset; check the Diffusion tab during prescription. Shift prescription in A/P if necessary to center prescription on the prostate Save Series Scan Note: If scanning a patient with brachytherapy seeds, prescribe the DWI sequence labeled (pt with seeds) at the end of the protocol. 8 1/5/2016

7 MRSI epsi_off Prescribe PRESS Box Scroll through Axial T2 slices to determine box placement, take into account the patient s biopsy history and avoid seminal vesicles in the base of the prostate. Leave a buffer slice in between the seminal vesicles and the PRESS Box. The maximum size the box should be is: R/L: 68, A/P: 43, S/I: 47. In the Graphic Rx Toolbox, select Spectra to see options Start and End. Select Start and End as the ends of your prescription box. Stretch the box in R/L and A/P to cover the prostate, avoiding surrounding fat. Make sure to scroll through the slices, as the prostate changes size across the slices. This may need to be repeated. 9 1/5/2016

8 Place SAT Bands Automatic SAT bands (invisible during prescription) are placed at the borders of the PRESS Box. In the SAT tab of the Graphic Rx Toolbox, use up to 6 additional, rotated SAT bands to eliminate signal from tissue bordering the prostate inside the PRESS Box. These will cut off the remaining lipid signal inside the PRESS box. Scroll through the slices to make sure SAT bands do not cover the prostate, but remove as much lipid signal as possible. Write the PRESS Box thickness on the data sheet. Save Right-click Duplicate the series to have a saved copy of the prescription Autoprescan Click the arrow to the right of the Scan button Research Download Click the arrow to the right of the Scan button Autoprescan When autoprescan is complete, the Line Width will appear in the upper right corner of the screen under the scan time. Record this value on the data sheet. 10 1/5/2016

9 Spectral Prescan Click the arrow to the right of the Scan button Spectral Prescan Start Options Display Parameters Set the coil number to 8 (or the highest) to receive signal from the endorectal coil Set the x-axis value for the upper screen to Magnitude using the selection button underneath the upper screen Record the x, y, and z initial shim values on the datasheet. Move the Delta Frequency slider to 200 and hit Apply, set the y-axis by using the button underneath the upper screen Move the sliders for x, y, and z (shown right) shim values to maximize the water peak on the screen. The water peak should have a smooth, thin shape, as shown below. Avoid: A wide peak A doublet (two peaks) A rough, jagged, or asymmetric peak Record the x, y, and z final shim values on the datasheet. Stop Save to record the water spectra. 11 1/5/2016

10 Start Move the Delta Frequency slider to -200 and hit Apply. Adjust the Delta Frequency Slider until the water peak is centered at 0. Select Stop, Save to record the full spectra. Done Acquisition Click the arrow to the right of the Scan button Research Display CVs Change CV epsi =1 ; opxres = 1 Click the arrow to the right of the Scan button Research Download The scan time in the upper left corner of the monitor should read ~06:56 after download. Scan Note: After the CV epsi is turned ON (=1) the workstation will freeze if you try to enter the prescription, autoprescan, or spectral prescan again, forcing a TPS reset. This is why we duplicate our prescription after placing SAT bands. If, for any reason, you need to restart the MRSI sequence after changing the CV epsi from 0 to 1, use the duplicated prescription and redo the normal autoprescan and spectral prescan steps. (This is also why we ve included epsi-off (=0) in the series name. EPSI stands for echo planar spectroscopic imaging, and is a research pulse sequence that the workstation software isn t built to handle.) 12 1/5/2016

11 PreGad Locs/slab = 20 for wide bore scanners (MB OR, CB widebore); = 22 for MBMR1 &2, MB Byers act_tr = 3300 for wide bore scanners (MB OR, CB widebore); = 3000 for MBMR1 &2, MB Byers Copy coverage Rx from AX T2 FSE (copy only the region, uncheck all other options: slice thickness, FOV, etc) Decrease slices to 22 locs/slab for MBMR1&2, MB Byers, Use: 20 locs/slab for wide bore scanners (CB wide bore and MB OR magnet) For very large prostates, more locs/slab can be used if needed, however remember this will decrease overall quality by worsening the temporal resolution. The injection delay must also be changed accordingly: MBMR1 &2, MB Byers 22 locs/slab 39 sec 24 locs/slab 44 sec 28 locs/slab 55 sec Wide Bore (MB OR & CB wide bore) 20 locs/slab 39 sec 22 locs/slab 44 sec 26 locs/slab 55 sec Save Series Change CVs saveinter = 1 (unless no endorectal coil used, then saveinter = 0 (default)) act_tr = 3300 (If MBMR1, MBMR2, or MB Byers) Use: act_tr = 3000 (If wide bore (MB OR or CB wide bore)) Download Scan 13 1/5/2016

12 DCE-nowrap Locs/slab = 20 for wide bore scanners (MB OR, CB widebore); = 22 for MBMR1 &2, MB Byers act_tr = 3300 for wide bore scanners (MB OR, CB widebore); = 3000 for MBMR1 &2, MB Byers Copy Rx from pregd-nowrap This series needs to have the same exact prescription as PreGd-nowrap. It also needs to immediately follow. If it does not immediately follow PreGd-nowrap, rerun PreGd-nowrap before DCE-nowrap. Save Series Change CVs act_tr = 3300 (If MBMR1, MBMR2, or MB Byers) Use: act_tr = 3000 (If wide bore (MB OR or CB wide bore)) Download Prep scan check injector for correct delay and accurate Gadavist quantity Tell the patient, During this next scan, we ll administer the contrast. You may feel a cold sensation in your arm during injection, but that s normal. Hit start scan at the same time the nurse starts the power injector 14 1/5/2016

13 IDEAL For MBMR1 & MBMR2 & MB-Byers: Copy prescription from the oblique T2s. Extend the # slices to32 and be sure to cover the prostate. For wide bore scanners and GEM coil array: Cover from top of heart to base of pelvis, # slices = 72. Will be a breathheld acquisition. Autoprescan Scan 15 1/5/2016

14 Post Processing Run PACC Select the Sagittal Scout and the Axial T2 FSE Use the Image (+/-) buttons to show the midline image on the sagittal and a mid-prostate image on the axial. Place the cursors in the rectum, near the superior and inferior dark bands on the sagittal image. Record these positions (cursor1:ap, SI; cursor 2: AP, SI) on the scan sheet. Place the cursors in the rectum at the coil indentations (should be bright spots) on the axial image. Record these positions (cursor 1: RL, AP; cursor 2: RL, AP) on the scan sheet. Select the Axial T1 3D, Axial T2 FSE, CUBE, and Ax DWI rfov b=1350 series for correction, this may take a minute, be sure not to exit until the coil-corrected series appear. Send all images to CB-Research or MB-Research. Send all images to PACS. Pro-tip: Begin sending the DCE images to CB or MB research before running PACC. DCE images take the longest time to transfer because there are so many. Since they do not require post processing, this will decrease overall transfer time. Always transfer to CB or MB research before sending to PACS, as researcher postprocessing takes place on the research servers, and researchers must process in full before radiologist can review images on PACS. Reformatting CUBE Images Run after PACC Be sure to run from the coil-corrected CUBE image Click Reformat from the main exam-viewing screen To create the COR image, select the SAG view and flip the prescription 180, modify to cover the prostate Slice thickness 1, Spacing 1 : Save as CUBE Coronal Reformat To create the SAG image, select the AX view and modify to cover the prostate Slice thickness 1, Spacing 1 : Save as CUBE Sagittal Reformat Send reformatted images to CB-Research and PACS Contact Information for Questions: Sue Noworolski, Associate Professor: Chris Sotto, Prostate Program Manager: Natalie Korn, Graduate Student: (o), (c), susan.noworolski@ucsf.edu , Christopher.Sotto@ucsf.edu (o), (c), natalie.korn@ucsf.edu 16 1/5/2016