All patients were examined with a 1.5-T whole-body MR imaging unit (Echospeed; GE Medical Systems, Milwaukee, Wisconsin) equipped with high-performance gradients and a manufacturer-supplied quadrature head coil. The following conventional sequences were performed: sagittal T1-weighted (300/14 [repetition time in ms/echo time in ms], one signal acquired), transverse T2-weighted fast spin-echo (3000/91, one signal acquired), transverse fast fluid-attenuated inversion-recovery (10,002/172, inversion time of 2.2 s, one signal acquired), transverse T1-weighted (500/14, one signal acquired), and transverse diffusion-weighted echo-planar (6000/99–100, one signal acquired, b values of 0 and 1000 s/mm2) MR imaging. The transverse sequences usually involved the use of a 5-mm section thickness with an intersection gap of 2.5 mm, a 256 × 192 matrix, the same imaging angle along the orbitomeatal line, and a 22- or 24-cm field of view. Gadopentetate dimeglumine (Multi-Hance; Bracco Diagnostics, Princeton, NJ) was administered with each MRI scan to allow for the evaluation of contrast enhancement. Contrast agent administration was performed intravenously in an identical manner with a power injector at a rate of 2 mL/s with a 20-gauge needle unless patient-related factors (e.g., small veins) necessitated the use of a needle with a different size.
Echo speed
Manufactured by GE Healthcare
Sourced in United States
Echo Speed is a compact, portable ultrasound system designed for general imaging applications. It provides high-quality imaging performance with advanced features to support a wide range of diagnostic examinations.
Automatically generated - may contain errors
Lab products found in correlation
13 protocols using echo speed
1
Standardized Brain MRI Protocol
2
MRI Imaging of Tumor Necrosis
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
MRI was performed using a clinical 1.5T MR magnet (Echo speed; GE Co., NY) with a rat coil for rat studies. Under isoflurane gas anesthesia, T1-weighted (T1W) and T2-weighted (T2W) spin-echo multi-slice coronal images were acquired. Then contrast enhanced T1-weighted (CE-T1W) images were obtained immediately after i.v. administration of Gd-DTPA (Bayer Schering Pharma AG, Berlin, Germany) at 0.2 mmol/kg. The related parameters are described below: Field of view (FOV) = 100 mm × 100 mm; T1W: Sequence SE, TR/TE = 550 ms/24 ms; T2W: Sequence FSE, TR/TE = 2920 ms/88 ms; CE-T1W: Sequence SE, TR/TE = 550 ms/60 ms.
Quantifications of tumor area were done by manually delineating the outline of the tumor mass on each T2W MRI slice covering the whole tumor. Tumor volume was calculated using the equation: tumor volume = Σ [tumor area on each slice × (slice thickness)]. The area of central nonenhancing region was delineated from CE-T1W images to estimate necrosis. The ratios of necrosis were defined as the volume of necrosis over that of entire tumor, i.e. necrosis ratio = Σ (area of necrosis × slice thickness)/(area of whole tumor × slice thickness) × 100%.
Quantifications of tumor area were done by manually delineating the outline of the tumor mass on each T2W MRI slice covering the whole tumor. Tumor volume was calculated using the equation: tumor volume = Σ [tumor area on each slice × (slice thickness)]. The area of central nonenhancing region was delineated from CE-T1W images to estimate necrosis. The ratios of necrosis were defined as the volume of necrosis over that of entire tumor, i.e. necrosis ratio = Σ (area of necrosis × slice thickness)/(area of whole tumor × slice thickness) × 100%.
3
MRI-based Tumor Volume and Necrosis Quantification
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
MRI was performed using a clinical 1.5 T whole body MRI scanner (Echo speed, GE Co., USA) with a wrist coil for mouse studies. The mouse was anesthesized with an animal anesthesia machine (Matrx VMR, GENE&I, Beijing, China), and placed supinely in a plastic holder. T1- and T2-weighted spin-echo multi-slice transverse images were acquired, and contrast enhanced T1-weighted (CE-T1W) images were obtained immediately after injection of Gd-DOTA (Dotarem, Guerbet, France) via a caudal vein at 0.2 mmol/kg.
Quantifications of tumor area were measured by manually delineating the outline of the tumor mass on T2-weighted MRI slices. Tumor volume was calculated with the equation: tumor volume = Σ (tumor area on each slice × slice thickness). Tumor doubling time (DT) was calculated based on the formula: DT = (T - T0) × log2 / (logV - logV0), where (T - T0) indicates the time interval between two measurements, V0 and V denote the tumor volume at the two points of measurement [38 (link)]. On CE-T1 images, the area of central nonenhancing region was delineated to estimate necrosis. The ratios of necrosis were defined as the volume of necrosis over that of entire tumor, i.e. necrosis ratio = Σ (area of necrosis × slice thickness) / (area of whole tumor × slice thickness) × 100%.
Quantifications of tumor area were measured by manually delineating the outline of the tumor mass on T2-weighted MRI slices. Tumor volume was calculated with the equation: tumor volume = Σ (tumor area on each slice × slice thickness). Tumor doubling time (DT) was calculated based on the formula: DT = (T - T0) × log2 / (logV - logV0), where (T - T0) indicates the time interval between two measurements, V0 and V denote the tumor volume at the two points of measurement [38 (link)]. On CE-T1 images, the area of central nonenhancing region was delineated to estimate necrosis. The ratios of necrosis were defined as the volume of necrosis over that of entire tumor, i.e. necrosis ratio = Σ (area of necrosis × slice thickness) / (area of whole tumor × slice thickness) × 100%.
4
Rat Brain Imaging with MRI Contrast
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Rats were anesthetized with 2% isoflurane during MRI observation in a wrist coil. A supine position was scanned using a 1.5 T MRI scanner (Echo speed; GE Healthcare). T1-weighted, T2-weighted and diffusion-weighted imaging (DWI) sequences were performed. Rats were injected with Magnevist (Schering; Bayer HealthCare Pharmaceuticals) through the tail vein and contrast-enhanced MR scanning (T1CE) was performed following injection.
5
Diffusion-Weighted Imaging Protocol for PACt-MD Study
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
As described previously (10 (link),20 (link)), participants from the PACt-MD study were all scanned on the same 3T GE Echospeed (General Electric) research-dedicated scanner at the Centre for Addiction and Mental Health. Whole-brain DWI including 30 gradient directions with b = 1000 s/mm2, 33 gradient directions with b = 3000 s/mm2, and 5 baseline scans with b = 0 s/mm2 was performed using an echo-planar imaging sequence with a dual spin-echo option to reduce eddy current–related distortions (echo time [TEb1000/b3000] = 110 ms, repetition time [TRb1000] = 1100 ms, [TRb3000] = 1200 ms; field of view = 25.6 cm; 128 × 128 matrix; 2.0 mm isotropic voxels; no gap; 81 slices). Axial slices were acquired parallel to the anterior commissure–posterior commissure line covering the whole brain. T1-weighted MRIs were acquired as sagittal 3-dimensional fast spoiled gradient-echo images (TE = 3 ms; TR = 6.7 ms; inversion time = 650 ms; flip angle 8°, field of view = 24 cm; number of excitations = 1, with 0.9 mm isotropic voxels, no gap, 81 slices). To correct for susceptibility-induced distortions, we also acquired 2 magnitude images with TE = 6.5 ms and TE = 8.5 ms, TR = 1000 ms, and field of view = 22 cm using an interleaved slice order, 64 × 64 matrix from which we estimated participant-specific field maps.
6
Comprehensive Body Composition Assessment
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Height and weight were measured with a stadiometer and balance-beam scale, respectively, with participants wearing light clothing and no shoes. BMI was quantified by weight in kilograms divided by height in meters-squared. Waist circumference was measured at a level midway between the lowest rib and the top of the iliac crest, as previously described (Alberga et al., 2012 (link)). Body composition was assessed by MRI with a 1.5-T system (EchoSpeed, signal 11 version; GE Medical Systems). Participants lay prone for whole-body cross sectional images using protocols by Ross et al. (1992) (link). The MRIs were analyzed using Slice-OMaticTM software, version 4.3; (Tomovision, Magog, QC, Canada). Fat-free mass (FFM) is defined as total lean tissue mass, including all fat-free skeletal muscle, organs, intestines, and bones, without adipose tissue, while fat mass (FM) represents the amount of visceral and subcutaneous adipose tissue. Percent body fat was calculated by dividing the amount of FM by total body mass (i.e., FM + FFM) × 100.
7
Comprehensive MRI Protocol for Diagnostics
8
High-resolution DWI Acquisition and Preprocessing
9
Longitudinal MRI Monitoring of Tumor Formation
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
MRI was performed once a week since week 8 to monitor tumor formation. Rats were anesthetized by a gas anesthesia machine (Matrix VMP; GENE&I, Beijing, China) with 2% isoflurane in the mixture of 20% oxygen/80% room air, and then were placed in specific wrist coil (Chenguang Medical Technologies Co., Ltd, Shanghai, China). A supine position was scanned for imaging acquisition using a 1.5 T MRI scanner (Echo speed; GE, Milwaukee, WI). DWI, T1 SPGR, and T2 FRF SE sequences were executed.
10
Standardized MRI Brain Imaging Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
We made MRI scans of the brain using a 1.5 or 3 T system (EchoSpeed; GE Healthcare, Milwaukee, WI) and a dedicated 8-channel head coil. MRIs were conducted according to a standardized protocol consisting of T1-weighted, T2-weighted, and fluid-attenuated inversion recovery images.10 (link) MRIs were graded using the method described before,10 (link) recognizing 4 stages of involvement: stage 0: no abnormalities; stage 1: periventricular white matter involvement around the centrum semiovale; stage 2: additional abnormalities in the subcortical white matter, internal capsule, external capsule, and corpus callosum; and stage 3: extension to the u fibers, basal ganglia, corticospinal tract, and/or infratentorial white matter. All MRIs were blinded and independently graded by a pediatric neuroradiologist (M.D.), a pediatric neurologist (J.M.P.v.d.H.), and a PhD student (J.J.A.v.d.D.). Discrepancies were solved by a consensus meeting.
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!