Intellispace portal 10

Conventional images were reformatted to a slice thickness of 3 mm. All images were sent to a commercial workstation (IntelliSpace Portal 10, Philips Healthcare) and a Carestream Vue picture archiving and communication system version 12 (Carestream Health) for evaluation.

All MRI images were evaluated using IntelliSpace Portal 10 (Philips Healthcare, the Netherlands). Two abdominal radiologists (G.X.L. and W.D.G., with 3 and 6 years of experience in gastrointestinal MRI, respectively), who were aware of the diagnosis of rectal carcinoma but blinded to other information, independently and successively performed the image analysis of 2D, 3D and CS-SENSE 3D data sets with at least a 4-week interval between analyses. Another reader (W.B., with over 20-years’ experience in abdominal MRI), aware of the diagnosis of rectal carcinoma but blinded to other information, pre-specified the slices to be measured during quantitative evaluation and ensured that they were the same among the three sequences. Readers could freely conduct multiplanar reconstruction in arbitrary orientations during their reads.

Conventional MR images were used for tumour extent measurements using ITK-SNAP-3.8.0 (University of Pennsylvania, Philadelphia, PA). The localization of the solid area of the tumour was performed on the T1WI structural image by three senior physicians, and the T2WI and enhanced scans were delineated. T2WI scans were marked, and the enhancement range was denoted as R^T2 and R^E. A region of interest (ROI) was selected to avoid surrounding blood vessels, tumour necrosis and regions of cystic degeneration. At the same time, for the enhanced scan images, we scored the degree of enhancement on a 1-4 scale (1-no enhancement, 2-slight enhancement, 3-moderate enhancement, and 4-significant enhancement).
APT mean (APT_mean) and range measurements (R^APT) were performed on APT images of tumors using IntelliSpace Portal 10.0 (Philips Medical, The Netherlands). T1WI structural images and the contralateral normal tissue areas served as references for the delineation of the range of APT image changes caused by tumors.
Finally, we compared R^APT with R^T2 and R^E to obtain the corresponding ratios (R^APT/E and R^APT/T2) to determine whether the range of APT increased.

All examinations were performed on a dual-layer spectral detector CT system (IQon, Philips Healthcare), with patients lying supine, arms above the head, in a single breath-hold. If necessary, patients received intravenous beta-blockers to achieve a pre-scan heart rate no higher than 65 bpm. Helical mode CCTA with retrospective ECG-gating was performed. Detailed CCTA parameters were as follows: tube potential, 120 kVp; tube load, maximum 220 mAs; gantry revolution time, 0.27 s; automatic exposure control (angular and longitudinal), combined xyz-axis; beam collimation geometry, 64 × 0.625 mm. Bolus tracking was used, with a region of interest (ROI) placed in the descending aorta, and acquisition was triggered when an attenuation threshold of 130 HU was reached. The occurrence of allergic reactions was recorded. Volume CT dose indexes and dose-length products were retrieved from the radiation-dose structured reports. Conventional- and spectral-based images were reconstructed using a standard kernel, iterative reconstruction (iDose 3, Philips Healthcare), and section thickness of 0.9 mm. Images were reviewed offline utilizing the manufacturer’s workstation (IntelliSpace Portal 10.0, Philips Healthcare).

All examinations were performed on a 64- or 256-slice CT system (IQon or iCT, respectively; Philips Healthcare, the Netherlands). The slice thickness was 3mm, the reconstruction algorithm was F: YB. CAC was calculated on standard CT-scans of the thorax using a dedicated post-processing software (Philips Intellispace Portal 10.0; Philips Healthcare) with the Agatston method [19 (link)].

A senior radiologist (T.L.) evaluated the MR images. Measurements were validated by a second senior radiologist (N. G. H.) based on independent assessment of a subset of study participants. The post-processing of the DTI raw data and the complete MRI analysis was performed with IntelliSpace Portal (IntelliSpace Portal 10.0, Philips Healthcare, Best, Netherlands).
To analyze the sciatic nerve in the DTI sequence, six subtotal freehand ROIs were drawn in six adjacent layers of color-coded fractional anisotropy images in correlation with the anatomical information of the b = 0 and 2D T2 TSE images. The average FA values of the six slices were then remeasured to obtain each subject’s final FA value. Fiber tracking of the nerve was performed for illustration.
In the PDFF maps, freehand subtotal ROIs were drawn on the three most proximal slices into each part of the quadriceps femoris muscle (vastus lateralis, intermedius, medialis, rectus femoris) and into the short and long heads of the biceps femoris muscle for determination of the average intramuscular fat fraction. The ROIs were drawn within 2 mm of the muscle boundaries. The differing area sizes (A_i) of the individual ROIs [ROI_i with individual fat fractions (FF_i)] were taken into account using the formula FF_mean_over_ROIs = sum (A_i ^∗ FF_i)/sum (A_i), where the sum is the summation over all ROIs.