scholarly journals Dynamic Evaluation of Notch Signaling-Mediated Angiogenesis in Ischemic Rats Using Magnetic Resonance Imaging

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Jia-qi Tian ◽  
Jia-jun Zheng ◽  
Xiao-zhu Hao ◽  
Le-kang Yin ◽  
Xiao-xue Zhang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Notch Signaling ◽  
Butyl Ester ◽  
Notch Signaling Pathway ◽  
Control Group ◽  
Vascular Density ◽  
Resonance Imaging ◽  
Sprague Dawley ◽  
Mri Scans

Objective. The Notch signaling pathway is involved in angiogenesis induced by brain ischemia and can be efficiently inhibited by the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butyl ester (DAPT). The aim of the present study was to noninvasively investigate the effect of DAPT treatment on angiogenesis in brain repair after stroke using magnetic resonance imaging (MRI). Methods. Sprague-Dawley rats (n=40) were subjected to 90 minutes of transient middle cerebral artery (MCA) occlusion and treated with PBS (n=20) or DAPT (n=20) at 72 hours after the onset of ischemia. MRI measurements including T2-weighted imaging (T2WI), susceptibility-weighted imaging (SWI), and cerebral blood flow (CBF) were performed at 24 hours after reperfusion and weekly up to 4 weeks using a 3-Tesla system. Histological measurements were obtained at each time point after MRI scans. Results. SWI showed that DAPT treatment significantly enhanced angiogenesis in the ischemic boundary zone (IBZ) with respect to the control group, with local CBF in the angiogenic area elevated, along with increases in vascular density confirmed by histology. Conclusion. Treatment of ischemic stroke with DAPT significantly augments angiogenesis, which promotes poststroke brain remodeling by elevating CBF level, and these processes can be dynamically monitored and evaluated by MRI.

scholarly journals Magnetic resonance imaging scans are not a reliable tool for predicting symptomatic acromioclavicular arthritis

2017 ◽  
Vol 10 (4) ◽  
pp. 250-254 ◽  
Author(s):  
Bijayendra Singh ◽  
Abhinav Gulihar ◽  
Praveen Bilagi ◽  
Arpit Goyal ◽  
Pallavi Goyal ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Bone Marrow ◽  
Magnetic Resonance ◽  
Clinical Symptoms ◽  
Bone Marrow Oedema ◽  
Control Group ◽  
Resonance Imaging ◽  
Level Of Evidence ◽  
Asymptomatic Group ◽  
Mri Scans

Background We investigated whether magnetic resonance imaging (MRI) scans can accurately diagnose arthritis of the acromioclavicular joint (ACJ) because it has recently been suggested that bone marrow oedema on MRI scans is a predictive sign of symptomatic ACJ arthritis. Methods The MRI scans of 43 patients (50 shoulders) who underwent ACJ excision for clinically symptomatic ACJ arthritis were compared to a control group of 43 age- and sex-matched patients (48 shoulders) who underwent an MRI scan for investigation of shoulder pain but did not have clinical symptoms or signs of ACJ arthritis. The scans were evaluated by an experienced musculoskeletal radiologist, who was blinded to the examination findings. Results Bone marrow oedema was present in only 15 (30%) shoulders in the ACJ excision group, although this was higher than the six shoulders in the asymptomatic group ( p = 0.03). Forty-one (82%) shoulders in the symptomatic group had grade III/IV ACJ arthritis compared to 31 (65%) in the asymptomatic group ( p = 0.05). However, 44 out of 48 (92%) shoulders in the asymptomatic group had signs of osteoarthritis on MRI scans. Conclusions In contrast to recent reports, the present study shows that MRI is not helpful in making the diagnosis of ACJ arthritis. A focused history and clinical examination should remain the mainstay for surgical decision making. Level of evidence Level 3

scholarly journals Magnetic resonance imaging (MRI) scans in patients with dorsal root ganglion stimulation

Pain Practice ◽  
2021 ◽  
Author(s):  
Marco Reining ◽  
Dirk Winkler ◽  
Joachim Boettcher ◽  
Juergen Meixensberger ◽  
Michael Kretzschmar
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Dorsal Root Ganglion ◽  
Dorsal Root ◽  
Resonance Imaging ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri

scholarly journals Predictors of Spondylolysis on Magnetic Resonance Imaging in Adolescent Athletes With Low Back Pain

2021 ◽  
Vol 9 (4) ◽  
pp. 232596712199546
Author(s):  
Takuji Yokoe ◽  
Takuya Tajima ◽  
Hiroshi Sugimura ◽  
Shinichirou Kubo ◽  
Shotarou Nozaki ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Low Back Pain ◽  
Back Pain ◽  
Magnetic Resonance ◽  
Neurological Symptoms ◽  
Low Back ◽  
Resonance Imaging ◽  
Advanced Imaging ◽  
Adolescent Athletes ◽  
Mri Scans

Background: Spondylolysis and undiagnosed mechanical low back pain (UMLBP) are the main causes of low back pain (LBP) in adolescent athletes. No studies have evaluated the difference in clinical and radiographic factors between these 2 conditions. Furthermore, it remains unclear which adolescent athletes with LBP should undergo advanced imaging examination for spondylolysis. Purpose: To compare the clinical and radiographic factors of adolescent athletes with spondylolysis and UMLBP who did not have neurological symptoms or findings before magnetic resonance imaging (MRI) evaluation and to determine the predictors of spondylolysis findings on MRI. Study Design: Cohort study, Level of evidence, 3. Methods: The study population included 122 adolescent athletes aged 11 to 18 years who had LBP without neurological symptoms or findings and who underwent MRI. Of these participants, 75 were ultimately diagnosed with spondylolysis, and 47 were diagnosed with UMLBP. Clinical factors and the following radiographic parameters were compared between the 2 groups: spina bifida occulta, lumbar lordosis (LL) angle, and the ratio of the interfacet distance of L1 to that of L5 (L1:L5 ratio, %). A logistic regression analysis was performed to evaluate independent predictors of spondylolysis on MRI scans. Results: Significantly more athletes with spondylolysis were male (82.7% vs 48.9%; P < .001), had a greater LL angle (22.8° ± 8.1° vs 19.3° ± 8.5°; P = .02), and had a higher L1:L5 ratio (67.4% ± 6.3% vs 63.4% ± 6.6%; P = .001) versus athletes with UMLBP. A multivariate analysis revealed that male sex (odds ratio [OR], 4.66; P < .001) and an L1:L5 ratio of >65% (OR, 3.48; P = .003) were independent predictors of positive findings of spondylolysis on MRI scans. Conclusion: The study findings indicated that sex and the L1:L5 ratio are important indicators for whether to perform MRI as an advanced imaging examination for adolescent athletes with LBP who have no neurological symptoms and findings.

Does diffusion-weighted magnetic resonance imaging have a place in the differential diagnosis of brucella sacroiliitis and seronegative spondyloarthropathy?

2020 ◽  
pp. 028418512093837
Author(s):  
Sunay Sibel Karayol ◽  
Kudret Cem Karayol
Keyword(s):  
Magnetic Resonance Imaging ◽  
Bone Marrow ◽  
Differential Diagnosis ◽  
Magnetic Resonance ◽  
Control Group ◽  
Resonance Imaging ◽  
Visual Evaluation ◽  
Mean Values ◽  
Diffusion Weighted ◽  
The Mean

Background The aim of this study is to investigate the role of diffusion-weighted imaging (DWI) in the differential diagnosis of sacroiliitis. Purpose To compare the sacroiliac magnetic resonance imaging (MRI) examinations of patients with suspected active sacroiliitis with patients with acute SpA MR findings and the DWI examinations of patients with acute brucella sacroiliitis, and thereby determine whether DWI can contribute to the differential diagnosis. Material and Methods A total of 84 patients were included in the study and were separated into three groups: group 1 (13 women, 6 men) comprised cases with brucella positive for sacroiliitis; group 2 (17 women, 19 men) comprised cases negative for brucella but with sacroiliitis; and group 3 (16 women, 13 men) comprised cases negative for brucella and sacroiliitis. Results The mean bone marrow apparent diffusion coefficient (ADC) values independently of edema were determined as 0.71 × 10−3 in sacroiliitis and brucella-positive patients, as 0.53 × 10−3 in brucella-negative and sacroiliitis-positive patients, and as 0.43 × 10−3 in the control group of brucella-negative sacroiliitis-negative patients. In the ADC measurements taken from areas of evident edema in patients with sacroiliitis, the mean values were 0.13 × 10−3 in the brucella-positive group and 0.12 × 10−3 in the brucella-negative group. Conclusion By adding DWI, which is a rapid MR sequence, to sacroiliac joint MR examination, normal bone marrow and bone marrow with sacroiliitis can be objectively differentiated with ADC measurements in addition to visual evaluation.

scholarly journals Analysis of Combined Treatment of Embolic Stroke in Rat with r-tPA and a GPIIb/IIIa Inhibitor

2005 ◽  
Vol 25 (1) ◽  
pp. 87-97 ◽  
Author(s):  
Guangliang Ding ◽  
Quan Jiang ◽  
Li Zhang ◽  
Zheng Gang Zhang ◽  
Lian Li ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Thrombolytic Therapy ◽  
Combination Treatment ◽  
Infarct Volume ◽  
Embolic Stroke ◽  
Control Group ◽  
Resonance Imaging ◽  
Cerebral Microvessels ◽  
Magnetic Resonance Imaging Mri

Suppression of platelet activation improves the efficacy of thrombolytic therapy for stroke. Thus, combination treatment with recombinant tissue plasminogen activator (r-tPA) and 7E3 F(ab′)2, a GPIIb/IIIa inhibitor that binds the platelet to fibrin, may improve the efficacy of thrombolytic therapy in embolic stroke. Magnetic resonance imaging (MRI) was used to monitor treatment response in rats subjected to embolic middle cerebral artery (MCA) occlusion (MCAo). Animals were randomized into treated ( n = 12) and control ( n = 10) groups and received intravenous combination therapy or saline, respectively, 4 hours after MCAo. Magnetic resonance imaging (MRI) measurements performed 1 hour after MCAo showed no difference between groups. However, an increased incidence (50%) of MCA recanalization was found in the treated group at 24 hours compared with 20% in the control group. The area of low cerebral blood flow at 24 and 48 hours was significantly smaller in the combination treatment group, and the lesion size, as indicated from the T2 and T1 maps, differed significantly between groups. Fluorescence microscopy measurements of cerebral microvessels perfused with fluorescein isothiocyanate-dextran and measurements of infarct volume revealed that the combination treatment significantly increased microvascular patency and reduced infarct volume, respectively, compared with the control rats. The efficacy of combination treatment 4 hours after ischemia is reflected by MRI indices of tissue perfusion, MCA recanalization, and reduction of lesion volume. The treatment also reduced secondary microvascular perfusion deficits.

scholarly journals Magnetic resonance imaging in the diagnosis of white matter signal abnormalities

2018 ◽  
Vol 31 (4) ◽  
pp. 362-371 ◽  
Author(s):  
Ravi Datar ◽  
Asuri Narayan Prasad ◽  
Keng Yeow Tay ◽  
Charles Anthony Rupar ◽  
Pavlo Ohorodnyk ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
White Matter ◽  
Magnetic Resonance ◽  
Tertiary Care ◽  
Diagnostic Utility ◽  
Care Hospital ◽  
Resonance Imaging ◽  
Clinical Tool ◽  
Diagnostic Challenge ◽  
Mri Scans

Background White matter abnormalities (WMAs) pose a diagnostic challenge when trying to establish etiologic diagnoses. During childhood and adult years, genetic disorders, metabolic disorders and acquired conditions are included in differential diagnoses. To assist clinicians and radiologists, a structured algorithm using cranial magnetic resonance imaging (MRI) has been recommended to aid in establishing working diagnoses that facilitate appropriate biochemical and genetic investigations. This retrospective pilot study investigated the validity and diagnostic utility of this algorithm when applied to white matter signal abnormalities (WMSAs) reported on imaging studies of patients seen in our clinics. Methods The MRI algorithm was applied to 31 patients selected from patients attending the neurometabolic/neurogenetic/metabolic/neurology clinics at a tertiary care hospital. These patients varied in age from 5 months to 79 years old, and were reported to have WMSAs on cranial MRI scans. Twenty-one patients had confirmed WMA diagnoses and 10 patients had non-specific WMA diagnoses (etiology unknown). Two radiologists, blinded to confirmed diagnoses, used clinical abstracts and the WMSAs present on patient MRI scans to classify possible WMA diagnoses utilizing the algorithm. Results The MRI algorithm displayed a sensitivity of 100%, a specificity of 30.0% and a positive predicted value of 74.1%. Cohen’s kappa statistic for inter-radiologist agreement was 0.733, suggesting “good” agreement between radiologists. Conclusions Although a high diagnostic utility was not observed, results suggest that this MRI algorithm has promise as a clinical tool for clinicians and radiologists. We discuss the benefits and limitations of this approach.

Safety Issues in Magnetic Resonance Imaging Scan with Retention of Olympus Long Clips in the Gastrointestinal Tract

2021 ◽  
Vol 17 ◽  
Author(s):  
Cheng-Yi Wang ◽  
Wei-Chou Chang ◽  
Hsin-Hung Huang ◽  
Wei-Kuo Chang ◽  
Yu-Lueng Shih ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Magnetic Resonance Imaging Scan ◽  
Resonance Imaging ◽  
Endoscopic Clip ◽  
Serious Adverse Event ◽  
Safety Issues ◽  
Endoscopic Clips ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri

Objective: Not all endoscopic clips are compatible with magnetic resonance imaging (MRI). The aim of this study is to investigate the safety of MRI-incompatible endoscopic clips in patients undergoing MRI scans. Methods: We retrospectively reviewed the medical records of patients who had received endoscopic clip placement of Olympus Long Clip MRI-incompatible clips and then had undergone MRI scans within two weeks in our hospital between 2014 and 2019. Results: A total of 44,292 patients had undergone an MRI examination at our hospital. Only 15 patients had MRI scans within two weeks after the endoscopic clip placement. Their median age was 65.5 years, and 12 of the 15 patients were men. At the time of the clip placement and MRI scan, four patients were taking anti-coagulation or anti-platelet agents. The indication for endoscopic clip placement of the 15 patients was mucosal/submucosal defect or hemorrhage and colonic perforation. Endoscopic clips were placed in the colon of 14 patients and in the stomach of only one patient for gastric hemorrhage. One patient experienced clip migration and three displayed artifacts in abdominal images. No patient complications of mortality, hemorrhage, or organ perforation occurred. Conclusion: No serious adverse event occurred during MRI scans of patients with MRI-incompatible clips in this study, suggesting that MRI-incompatible clips may be safe to use in MRI scans. However, this does not guarantee the safety of the Long Clip for MRI scans, as further tests are needed to verify that this clip is safe for use during MRI.

Magnetic Resonance Imaging to Investigate the Clinical Applicability of the Medial Femoral Trochlea Osteochondral Flap Within the Wrist

Hand ◽  
2022 ◽  
pp. 155894472110643
Author(s):  
Jimmy H. Daruwalla ◽  
Jan Skrok ◽  
Mitchell A. Pet ◽  
Aviram M. Giladi ◽  
James P. Higgins
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Sagittal Plane ◽  
Convex Surface ◽  
Radius Of Curvature ◽  
Resonance Imaging ◽  
Femoral Trochlea ◽  
Average Ratio ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri

Background: The medial femoral trochlea (MFT) osteochondral flap is employed for reconstruction of unsalvageable scaphoid proximal pole nonunions. The convex surface of the cartilage-bearing proximal trochlea is used to replace the similarly contoured proximal scaphoid and articulate with the concave scaphoid fossa of the radius. A magnetic resonance imaging (MRI) comparison of the shape of the MFT as it relates to the native proximal scaphoid has not been previously performed. Our study aimed to quantifiably compare the shape of the MFT, proximal scaphoid, and scaphoid fossa. Methods: Using imaging processing software, we measured radius of curvature of the articular segments in MRI scans of 10 healthy subjects’ wrists and knees. Results: Compared with the scaphoid fossa, average ratio of the radius of circumference of the proximal scaphoid was 0.79 and 0.78 in the coronal and sagittal planes, respectively. Compared with the scaphoid fossa, average ratio of the radius of circumference of the MFT was 0.98 and 1.31 in the coronal and sagittal planes, respectively. The radius of curvature of the MFT was larger than the proximal scaphoid, in the coronal and sagittal planes. In the coronal plane, the MFT radius of curvature is nearly identical to the scaphoid fossa, a closer match than the scaphoid itself. In the sagittal plane, the radius of curvature of the MFT was larger than the radius of curvature of the scaphoid fossa. Conclusions: Our data suggest that the radius of curvature, in the sagittal and coronal planes, of the MFT and proximal scaphoid is disparate.

The Difference between Computed Tomography and Magnetic Resonance Imaging Measurements of Tibial Tubercle–Trochlear Groove Distance for Patients with or without Patellofemoral Instability: A Systematic Review and Meta-analysis

2019 ◽  
Vol 33 (08) ◽  
pp. 768-776 ◽  
Author(s):  
Si Heng Sharon Tan ◽  
Beatrice Ying Lim ◽  
Kiat Soon Jason Chng ◽  
Chintan Doshi ◽  
Francis K.L. Wong ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Computed Tomography ◽  
Magnetic Resonance ◽  
Patellofemoral Instability ◽  
Tibial Tubercle ◽  
Control Group ◽  
Trochlear Groove ◽  
Resonance Imaging ◽  
The Mean ◽  
Ct And Mri

AbstractThe tibial tubercle–trochlear groove (TT–TG) distance was originally described for computed tomography (CT) but has recently been used on magnetic resonance imaging (MRI) without sufficient evidence demonstrating its validity on MRI. The current review aims to evaluate (1) whether there is a difference in the TT–TG distances measured using CT and MRI, (2) whether both the TT–TG distances measured using CT and MRI could be used to differentiate between patients with or without patellofemoral instability, and (3) whether the same threshold of 15 to 20 mm can be applied for both TT–TG distances measured using CT and MRI. The review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRSIMA) guidelines. All studies that compared TT–TG distances either (1) between CT and MRI or (2) between patients with and without patellofemoral instability were included. A total of 23 publications were included in the review. These included a total of 3,040 patients. All publications reported the TT–TG distance to be greater in patients with patellofemoral instability as compared to those without patellofemoral instability. This difference was noted for both TT–TG distances measured on CT and on MRI. All publications also reported the TT–TG distance measured on CT to be greater than that measured on MRI (mean difference [MD] = 1.79 mm; 95% confidence interval [CI]: 0.91–2.68). Pooling of the studies revealed that the mean TT–TG distance for the control group was 12.85 mm (95% CI: 11.71–14.01) while the mean TT–TG distance for patients with patellofemoral instability was 18.33 mm (95% CI: 17.04–19.62) when measured on CT. When measured on MRI, the mean TT–TG distance for the control group was 9.83 mm (95% CI: 9.11–10.54), while the mean TT–TG distance for patients with patellofemoral instability was 15.33 mm (95% CI: 14.24–16.42). Both the TTTG distances measured on CT and MRI could be used to differentiate between patients with and without patellofemoral instability. Patients with patellofemoral instability had significantly greater TT–TG distances than those without. However, the TT–TG distances measured on CT were significantly greater than that measured on MRI. Different cut-off values should, therefore, be used for TT–TG distances measured on CT and on MRI in the determination of normal versus abnormal values. Pooling of all the patients included in the review then suggest for 15.5 ± 1.5 mm to be used as the cut off for TT–TG distance measured on CT, and for 12.5 ± 2 mm to be used as the cut-off for TT–TG distance measured on MRI. The Level of evidence for this study is IV.

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