Recovery Fast Spin-echo Imaging Research Articles

The value of the cinematic volume rendering technique: magnetic resonance imaging in diagnosing tumors associated with the brachial plexus

PurposeTo examine the diagnostic advantages and clinical application value of the cinematic volume rendering technique (cVRT) when evaluating the relationship between the brachial plexus, peripheral tumor lesions, and blood vessels.Materials and methodsSeventy-nine patients with brachial plexus tumors between November 2012 and July 2022 were enrolled in our study. All patients underwent T1WI, T2WI, three-dimensional short recovery time reversal recovery fast spin-echo imaging (3D-STIR-SPACE), and the T1WI enhancement sequence. In addition, cVRT was used to render and obtain a three-dimensional model that clearly showed the location and tissue structure of the brachial plexus nerves and the tumor in all directions.ResultsSeventy-one patients (mean age, 47.1 years; 33 males, 38 females) with tumors around the brachial plexus were included in the study. The brachial plexus nerve, surrounding tumor lesions, and vascular anatomy of all patients were well displayed with cVRT. The tumors of 37 patients manifested as unilateral or bilateral growths along the brachial plexus nerve and were fusiform, spherical, or multiple beaded; seven patients' tumors pushed against the brachial plexus nerve and were circular, lobular, or irregular; sixteen patients' tumors encircled the brachial plexus nerve and were spherical; and eleven patients' tumors infiltrated the brachial plexus nerve and had irregular morphology. The mass has a moderately uniform or uneven signal on T1WI and a high or mixed signal on T2WI. After enhancement, the signal was evenly or unevenly strengthened.ConclusionscVRT clearly showed the origin of tumors associated with the brachial plexus and their relationship with the nerves and peripheral blood vessels, providing reliable information for clinical diagnosis and treatment.

A New OATP-Mediated Hepatobiliary-Specific Mn(II)-Based MRI Contrast Agent for Hepatocellular Carcinoma in Mice: A Comparison With Gd-EOB-DTPA.

Growing concerns about the safety of gadolinium (Gd)-based contrast agents have reinforced the need for the development of Gd-free MRI contrast agents (CAs) that are effective in imaging liver tumors. To evaluate the ability of Mn-BnO-TyEDTA MRI CA to detect hepatocellular carcinoma in a mouse model of implanted liver tumor. Prospective. Thirteen orthotopically implanted liver tumor mice. 3.0 T/precontrast and postcontrast T1-weighted fast spoiled gradient recalled echo and T2-weighted fast recovery fast spin-echo imaging with fat suppression. The relative enhancement ratio was calculated and statistically compared. Lesion detection in postcontrast images was analyzed by calculations of area under the curve (AUC, the increases in liver-to-tumor contrast-to-noise ratio [∆CNR] vs. time curve). Mn or Gd levels were measured in the liver and tumoral tissues by inductively coupled plasma-mass spectrometry. Tumor specimens were stained with hematoxylin and eosin (H&E) and the expression of organic anion transfer peptide (OATP)1B1 was evaluated by immunofluorescence (IF) staining and mean fluorescence intensity (MFI) was calculated. Unpaired t-test and two-tailed paired t-test. P < 0.05 was considered statistical significance. Mn-BnO-TyEDTA and Gd-EOB-DTPA demonstrated nearly identical enhancement patterns in the liver, tumor, and psoas muscle and no difference in lesion detection (AUC10-30, Mn =851 ∆CR·min, AUC10-30, Gd =823 ∆CR·min). A Significant higher concentration of metal (Mn or Gd) was found in the liver compared to the tumor ([Mn]liver =0.88 ± 0.07 μmmol/g, [Mn]tumor =0.49 ± 0.05 μmmol/g, [Gd]liver =0.65 ± 0.07 μmmol/g, [Gd]tumor =0.27 ± 0.04 μmmol/g). IF staining showed significantly decreased expression of OATP1B1 in the tumor core compared to the liver (MFItumor =5.28 ± 1.54, MFIliver =25.49 ± 3.41). Mn-BnO-TyEDTA can provide comparable hepatobiliary tumor contrast enhancement to Gd-EOB-DTPA. 1 TECHNICAL EFFICACY: Stage 1.

Fluorine-19 Fast Recovery Fast Spin Echo Imaging for Mapping 5-Fluorouracil

We investigated the effects of fast recovery (FR) to increase the sensitivity of fluorine-19 ((19)F) fast spin echo (FSE) in mapping 5-fluorouracil (5-FU) and its metabolites. We added an additional 90 degrees pulse (which flips back longitudinal magnetization at the end of the sequence) to the chemical shift selective (19)F FSE pulse sequence. In 5-FU solution, FR remarkably improved the signal-to-noise (S/N) ratio of (19)F 5-FU images, having higher effects with shorter repetition time and smaller echo train numbers. In animal studies, FR produced a conspicuous increase in (19)F signals in the urinary bladder. FR effects for (19)F signals in the liver were smaller than those in other organs but still substantial. Utilization of FR in (19)F FSE images promises more sensitive observation of (19)F metabolite maps of 5-FU and other (19)F-containing compounds that have relatively long relaxation times.

Full‐brain T1 mapping through inversion recovery fast spin echo imaging with time‐efficient slice ordering

Brain T1 mapping has important clinical applications in detecting brain disorders. Conventional T1 mapping techniques are usually based on inversion recovery spin echo (IRSE) imaging or its more time-efficient counterpart inversion recovery fast spin echo (IRFSE) imaging because they can deliver good image quality. Multiple inversion times are required to accurately estimate T1 over a wide range of values. Without acquisition optimization, both the IRSE and the IRFSE T1 mapping techniques require long scan times to image the whole brain. To reduce the scan time and maintain the quality of the T1 maps, we propose a new full-brain T1 mapping pulse sequence based on a multislice inversion recovery fast spin echo imaging using a time-efficient slice ordering technique.

Three-dimensional fast recovery fast spin-echo imaging of the inner ear and the vestibulocochlear nerve.

The aim of this study was to assess the performance of three-dimensional fast recovery fast spin-echo (3DFRFSE) for imaging of the inner ear as well as the facial and vestibulocochlear nerves. We evaluated 3DFRFSE sequences, comparing it with 3D fast spin-echo (3DFSE) in a water phantom and in 12 normal volunteers. We also examined 66 patients using 3DFRFSE sequence and assessed the visualization of their pathologies. In a water phantom study, signal intensity (SI) on 3DFRFSE was higher than that on 3DFSE at the same TR ranging from 1,500 to 6,000 ms. In normal volunteers, 3DFRFSE with TR of 2,800 ms showed comparable SI, and signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) superior to those on 3DFSE with TR of 5,000 ms. In clinical setting, 3DFRFSE was useful in demonstrating anatomic details in the labyrinth and pathologic findings of inner ear. The 3DFRFSE can provide high-resolution heavily T2-weighted images (T2WI) with shorter scan time than 3DFSE without significant disadvantage. The 3DFRFSE is a beneficial technique for evaluation of lesions in the inner ear as well as the facial and vestibulocochlear nerves.