Regional Cerebral Plasma Volume Response to Carbon Dioxide Using Magnetic Resonance Imaging

Background Noninvasive techniques used to determine the changes in cerebral blood volume in response to carbon dioxide are hampered by their limited spatial or temporal resolution or both. Using steady state contrast-enhanced magnetic resonance imaging, the authors determined regional changes in cerebral plasma volume (CPV) induced by hypercapnia in halothane-anesthetized rats. Methods Cerebral plasma volume was determined during normocapnia, hypercapnia and recovery in the dorsoparietal neocortex and striatum of each hemisphere, in cerebellum, and in extracerebral tissue of rats with either intact carotid arteries (group 1) or unilateral common carotid ligation (group 2). Another group was studied without injection of a contrast agent (group 3). Results Hypercapnia (partial pressure of carbon dioxide in arterial blood [PaCO2] approximately 65 mmHg) resulted in a significant increase in CPV in the striatum (+42 +/- 8%), neocortex (+34 +/- 6%), and cerebellum (+49 +/- 12%) compared with normocapnic CPV values (group 1). Carotid ligation (group 2) led to a marked reduction of the CPV response to hypercapnia in the ipsilateral striatum (+23 +/- 14%) and neocortex (+27 +/- 17%) compared with the unclamped side (+34 +/- 15% and +38 +/- 16%, respectively). No significant changes in CPV were found in extracerebral tissue. In both groups, the CPV changes were reversed by the carbon dioxide washout period. Negligible changes in contrast imaging were detected during hypercapnia without administration of the contrast agent (group 3). Conclusions The contrast-enhanced magnetic resonance imaging technique is sensitive to detect noninvasively regional CPV changes induced by hypercapnia in rat brain. This could be of clinical interest for determining the cerebrovascular reactivity among different brain regions.

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Contrast enhanced magnetic resonance imaging in assessment of aortic atherosclerosis and its relation to severity of myocardial injury due to infarction

Russian Journal of Cardiology ◽

10.15829/1560-4071-2019-12-10-14 ◽

2019 ◽

pp. 10-14

Author(s):

A. S. Maksimova ◽

V. E. Sinitsyn ◽

Yu. B. Lishmanov ◽

W. Yu. Ussov

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Myocardial Injury ◽

Aortic Wall ◽

Aortic Atherosclerosis ◽

Resonance Imaging ◽

Contrast Enhanced ◽

Group 3 ◽

Group 2 ◽

Group 1

Aim. To study the contrast enhanced magnetic resonance imaging (CE-MRI) role in assessment of aortic atherosclerosis and its relation to severity of myocardial injury in myocardial infarction (MI) patients which underwent cardiac MRI before coronary artery bypass grafting and Dor or Menicanti procedures.Material and methods. The study included 42 patients (38 men, 4 women) who underwent CE-MRI (mean age 57,7±8,75 years). In order to analyze the aortic atherosclerosis, axial T1 weighted images before and after 10-15 minutes after CE was evaluated. Along with visual analysis, the diameter, thickness of the aortic wall, and index of enhancement (IE) of T1 weighted image (WI) (TR=400-650 ms, TE=12-20 ms), as the ratio of postand precontrast intensities of the aortic wall: IE=(Intensity T1-WI post-contrast)/ (Intensity T1-WI pre-contrast) were determined. According to the cardiac CEMRI, the proportion of left ventricle (LV) injury as the ratio of the MI injury and theLV mass was estimated.Results. Depending on aortic IE value, patients were divided into three groups: group 1 (9 people) with IE ≤1,05; group 2 (15 people) with 1,05< IE ≤1,15; group 3 (18 people) with IE >1,15. We compared the descending aortic wall thickness and the diameter among these groups. To identify intergroup differences one-way ANOVA with Bonferroni correction was carried out. There were no significant differences in the descending aortic diameters (F=0,15; p=0,86): group 1 — 2,41±0,33, group 2 — 2,54±0,63, group 3 — 2,53±0,51 cm. The thickness of the aortic wall in groups was 2,05±0,58 mm, 3,34±0,68 mm and 3,80±0,46 mm (F=17,39; p< 0,001), respectively. The first and second, first and third groups were distinguished, and there was no significant difference between the second and third groups. Between groups 1, 2 and 3 were also noted the increase and differences in proportion of LV injury, which amounted to 0,11±0,03 with a minimum IE (group 1), with an intermediate IE (group 2) — 0,19±0,08, and with high IE — 0,25±0,15.Conclusion. CE-MRI of the aortic wall can be used as a method of visualizing atherosclerosis and predicting the complications of aortic atherosclerosis. Moreover, the assessment of aortic atherosclerosis can be used in combination with conventional heart examination. The increased CE into the aortic wall in patients with advanced atherosclerosis is usually associated with a greater severity of myocardial injury. During cardiac CE-MRI it is advisable to assess the descending aorta state by calculation of IE T1-WI MRI to clarify the atherosclerosis severity and cardiovascular risk.

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Role of biometric characteristics of the uterine junctional zone in fertility outcomes in patients with adenomyosis

Journal of obstetrics and women s diseases ◽

10.17816/jowd65046 ◽

2021 ◽

Vol 70 (3) ◽

pp. 41-50

Author(s):

Ekaterina K. Orekhova ◽

Olga A. Zhandarova ◽

Igor Yu. Kogan

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Pregnancy Outcomes ◽

Adverse Pregnancy Outcomes ◽

Resonance Imaging ◽

Junctional Zone ◽

History Of ◽

Group 2 ◽

Adverse Pregnancy ◽

Group 1

BACKGROUND: The uterine junctional zone is the inner part of the myometrium. Dysfunction of the zone may underlie the pathogenesis of adenomyosis and its clinical manifestations, while biometric characteristics of the zone are currently considered as promising early diagnostic criteria for this disease. Adenomyosis has traditionally been associated with parity and intrauterine interventions, primarily in older patients. However, modern imaging tools often allow diagnosing the disease in young patients with infertility and an unburdened gynecological history. It is assumed that the detection of changes in the structure and function of the uterine junctional zone in adenomyosis can be the basis for predicting fertility outcomes and complications of pregnancy, as well as for the development of promising therapeutic strategies at the pregravid stage. AIM: The aim of this study was to assess the influence of biometric characteristics of the uterine junctional zone on pregnancy outcomes, depending on the parity and intrauterine interventions in patients with adenomyosis. MATERIALS AND METHODS: This prospective study included 102 patients aged 2239 years old with ultrasound features of adenomyosis who were going to conceive. The patients were divided into two groups: Group 1 (n = 58) consisted of nulliparous patients with no history of previous intrauterine interventions, and Group 2 (n = 44) comprised multipara women with a history of labor and / or intrauterine interventions. Using magnetic resonance imaging, we evaluated minimal, average and maximal junctional zone thicknesses, junctional zone deferential and a ratio of junctional zone thickness to myometrium thickness. Thresholds of biometric characteristics of the uterine junctional zone for adverse pregnancy outcomes were estimated. RESULTS: The frequencies of pregnancy and retrochorial hematoma in patients of Groups 1 and 2 in the first trimester of pregnancy did not differ significantly and amounted to 43.1% and 38.6%, 13.8% and 22.7%, respectively, p 0.05. Adverse pregnancy outcomes were diagnosed in 63.8% of patients in Group 1 and in 68.2% of patients in Group 2, p 0.05. In Group 1, the frequency of retrochorial hematoma depended on the initial junctional zone deferential, as well as on the initial average and maximal junctional zone thicknesses, junctional zone deferentials and ratios of junctional zone thickness to myometrium thickness, which, with an adverse pregnancy outcome, were 1.72.5 times higher than those in patients with a favorable outcome, p 0.05. In Group 2, adverse pregnancy outcomes were recorded with significantly higher values of average and maximal junctional zone thicknesses and junctional zone deferential. ROC curves were constructed using data of logistic regression analysis based on biometric characteristics of the uterine junctional zone to predict spontaneous abortion and infertility in patients with adenomyosis. CONCLUSIONS: Fertility outcomes in patients with adenomyosis depend on a complex of biometric characteristics of the uterine junctional zone as determined by magnetic resonance imaging.

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Diagnostic value of magnetic resonance imaging in perimesencephalic and nonperimesencephalic subarachnoid hemorrhage of unknown origin

Journal of Neurosurgery ◽

10.3171/2010.6.jns10310 ◽

2011 ◽

Vol 114 (4) ◽

pp. 1003-1007 ◽

Cited By ~ 40

Author(s):

Homajoun Maslehaty ◽

Athanassios K. Petridis ◽

Harald Barth ◽

Hubertus Maximilian Mehdorn

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Mr Imaging ◽

Unknown Origin ◽

Diagnostic Value ◽

Digital Subtraction ◽

Resonance Imaging ◽

Bleeding Pattern ◽

Group 2 ◽

Group 1

Object The aim of this study was to evaluate the diagnostic value of MR imaging in perimesencephalic (PM) and nonperimesencephalic (non-PM) subarachnoid hemorrhage (SAH) of unknown origin. Methods The authors conducted a retrospective review of all patients with SAH (1226 patients) in their department between January 1991 and December 2008. Included in the study were cases of spontaneous SAH diagnosed using CT scans obtained within 24 hours of the initial symptoms and initially negative digital subtraction (DS) angiograms. Patients with traumatic SAH and an unknown history were excluded from the study. Patients with initially negative DS angiograms were divided into 2 groups: Group 1, a typically PM bleeding pattern (PM SAH); and Group 2, a non-PM bleeding pattern (non-PM SAH) such as hemorrhage in the sylvian or interhemispheric fissure. Cranial MR imaging including the craniocervical region was performed within 72 hours after SAH was diagnosed in all patients in Groups 1 and 2. Results One thousand sixty-eight patients underwent DS angiography, and among them were 179 (16.7%) with negative angiograms—47 patients (26.3%) from Group 1 and 132 patients (73.7%) from Group 2. Magnetic resonance imaging demonstrated no bleeding sources in any case (100% negative). Thirty-four patients in Group 1 and 120 patients in Group 2 underwent a second DS angiography study. Digital subtraction angiography revealed an aneurysm as the bleeding source in 1 case in Group 1 and in 13 cases in Group 2. Conclusions Magnetic resonance imaging of the brain and craniocervical region did not produce additional benefit for the detection of a bleeding source and the therapy administered for PM SAH and non-PM SAH (100% negative). The costs of this examination exceeded the clinical value. Despite the results of this study, MR imaging should be discussed on a case-by-case basis because rare bleeding sources are periodically diagnosed in cases of non-PM SAH. A second-look DS angiogram is necessary because aneurysmal hemorrhage occasionally produces PM SAH as well as non-PM SAH. Further prospective studies are needed to verify the authors' results in the future.

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Impact of neoadjuvant therapy in downstaging of lower rectal adenocarcinoma and the role of pelvic magnetic resonance in staging

Revista do Colégio Brasileiro de Cirurgiões ◽

10.1590/0100-69912016002006 ◽

2016 ◽

Vol 43 (2) ◽

pp. 102-109 ◽

Cited By ~ 2

Author(s):

Karina Dagre Magri ◽

Fang Chia Bin ◽

Fernanda Bellotti Formiga ◽

Thiago da Silveira Manzione ◽

Caroline Merci Caliari de Neves Gomes ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Neoadjuvant Therapy ◽

Rectal Adenocarcinoma ◽

Resonance Imaging ◽

Radiological Findings ◽

Pelvic Magnetic Resonance Imaging ◽

Group 2 ◽

Locoregional Staging ◽

Group 1

ABSTRACT Objective: to evaluate the effect of neoadjuvant therapy on the stage (TNM) of patients with rectal adenocarcinoma and validate the use of MRI as a method of determining locoregional stage. Methods: we conducted a retrospective study of 157 patients with lower rectum adenocarcinoma, whom we divided into two groups: Group 1, 81 patients (52%) who had undergone surgical treatment initially, with the purpose to analyze the accuracy of locoregional staging by pelvic magnetic resonance imaging throug the comparison of radiological findings with pathological ones; Group 2, 76 patients (48%), who had been submitted to neoadjuvant therapy (chemotherapy and radiation) prior to definitive surgical treatment, so as to evaluate its effects on the stage by comparing clinical and radiological findings with pathology. Results: In group 1, the accuracy of determining tumor depth (T) and lymph node involvement (N) was 91.4% and 82.7%, respectively. In group 2, neoadjuvant therapy decreased the T stage, N stage and TNM stage in 51.3%, 21% and 48.4% of cases, respectively. Conclusion: neoadjuvant therapy in patients with rectal adenocarcinoma is effective in decreasing disease stage, and pelvic magnetic resonance imaging is effective for locoregional staging.

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Prognostic value of magnetic resonance imaging in the evaluation of physical therapy outcomes in patients with adhesive capsulitis

Turkish Journal of Physical Medicine and Rehabilitation ◽

10.5606/tftrd.2021.5139 ◽

2021 ◽

Vol 67 (2) ◽

pp. 146-154

Author(s):

Sacide Nur Saraçgil Coşar ◽

Selin Ozen ◽

Ali Niyazi Kurtcebe ◽

Mehmet Coşkun ◽

Oya Ümit Yemişci

Keyword(s):

Magnetic Resonance Imaging ◽

Physical Therapy ◽

Magnetic Resonance ◽

Shoulder Pain ◽

Clinical Diagnosis ◽

Adhesive Capsulitis ◽

Resonance Imaging ◽

Mri Findings ◽

Group 2 ◽

Group 1

Objectives: This study aims to investigate whether the treatment outcomes of patients with a clinical diagnosis of adhesive capsulitis (AC) and magnetic resonance imaging (MRI) findings consistent with AC undergoing physical therapy (PT) differs to those with AC in the absence of these MRI findings. Patients and methods: Between January 2012 and October 2012, a total of 30 patients (8 males, 22 females; mean age 55.6±12.1 years; range, 35 to 85 years) with a clinical diagnosis of AC underwent MRI of the index shoulder. The MRI scans were evaluated for findings associated with AC: intensity of the inferior glenohumeral ligament (IGHL) and rotator interval (RI). All patients received a total of 15 sessions of PT: hot pack, transcutaneous electrical nerve stimulation, ultrasound, and shoulder exercises. The patients were assessed for shoulder range of motion (ROM) using the Visual Analog Scale (VAS) for shoulder pain, Quick Disabilities of the Arm Shoulder and Hand (Q-DASH), and Health Assessment Questionnaire (HAQ) prior to and following completion of PT. Results: Of the patients, 21 had no MRI findings consistent with AC (Group 1), nine patients had changes in the IGHL and/or RI characteristic of AC (Group 2). In both groups, there was a significant improvement in active and passive shoulder ROM and VAS scores for shoulder pain at rest (Group 1: p<0.001, Group 2: p=0.017) with movement (Group 1: p<0.001, Group 2: p=0.007) and at night (Group 1: p<0.001, Group 2: p=0.012) following PT. However, there was no significant inter-group difference in scores. Similar findings were recorded for Q-DASH and HAQ. Conclusion: Based on these study findings, the presence of characteristic MRI findings of AC with a clinical diagnosis do not predict clinical response to physical therapy.

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Investigation of the Effect of Written and Visual Information on Anxiety Measured Before Magnetic Resonance Imaging: Which Method is Most Effective?

Medicina ◽

10.3390/medicina56030136 ◽

2020 ◽

Vol 56 (3) ◽

pp. 136

Author(s):

Burkay Yakar ◽

Edibe Pirinçci

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Trait Anxiety ◽

State Anxiety ◽

Visual Information ◽

Control Group ◽

Resonance Imaging ◽

Written Information ◽

Group 3 ◽

Group 2

Background and objective: Magnetic resonance imaging (MRI) causes severe anxiety in some patients. Anxiety during MRI leads to prolongation of the procedure and deterioration of image quality, resulting in loss of labor and cost increase. The aim of this study was to investigate the effect of written and visual information on state anxiety in patients undergoing MRI. Material and Methods: A cross-sectional prospective study was conducted with 294 participants. The study was carried out between January 2019 and March 2019 at the Radiology Clinic of the tertiary university hospital. The participants were divided into 3 groups as group 1 (control group), group 2 (written information) and group 3 (visual information). The trait anxiety and state anxiety of the participants were measured by State-Trait Anxiety Inventory (STAI) inventory, which can measure both anxiety status. Results: There was no statistically significant difference between demographic characteristics and trait anxiety scores (p = 0.20) of all three groups. The state anxiety scores of group 3 were statistically lower than the group 2 (p < 0.001) and control group (p < 0.001). The state anxiety scores of group 2 were statistically lower than control group (p < 0.001). Conclusion: MRI anxiety can be reduced by visual and written information. Visual information may be more effective in reducing MRI anxiety than written information.

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Abstract 9576: Predictors of Silent Cerebral Events Detected on Magnetic Resonance Imaging in Patients After Atrial Fibrillation Ablation

Circulation ◽

10.1161/circ.130.suppl_2.9576 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Thomas Deneke ◽

Karin Nentwich ◽

Patrick Müller ◽

Markus Roos ◽

Joachim Krug ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Atrial Fibrillation ◽

Magnetic Resonance ◽

Left Atrial ◽

Resonance Imaging ◽

Af Ablation ◽

Cerebral Mri ◽

Group 5 ◽

Group 2 ◽

Group 1

Introduction: Silent cerebral events (SCE) have been identified on magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation. Silent cerebral lesions represent irreversible cerebral damage, comparative analysis using a consistent MRI definition is missing and factors influencing the risk of SCE are poorly understood. Methods: 351 Patients undergoing AF ablation underwent post-ablation cerebral MRI. SCE were identified based on a sensitive definition using a 1.5Tesla MRI including DWI and ADC-map (but not including FLAIR). AF ablation was performed either using irrigated single-tip radiofrequency (RF) ablation (group 1, N=73), phased RF pulmonary vein isolation (PVI) (group 2, N=129), endoscopically-guided laser balloon (group 3, N=41), cryo-balloon PVI (group4, N=34) and irrigated RF multipolar catheters (nMARQ) (group 5, N=73). Differences in regard to SCE rates were analyzed. Results: In group 1 22%, in group 2 37%, in group 41%, in group 4 21% and in group 5 27% of patients had documented SCE. There was a significantly higher incidence of SCL in patients with compared to without exchanges of catheters over a single transseptal sheath (34% vs. 18%, p=0.007) and in patients with left atrial dilation (48% vs. 30%, p=0.01). In a subgroup analysis incidence of SCE was lower when patients were ablated under continued oral anticoagulation (11%) compared to novel oral anticoagulants (33%) or without continuous appropriate anticoagulation bridged with low-molecular weight heparin (45%). Documented left atrial low-voltage areas were associated with a higher incidence of SCE (46% versus 24% in the control group). Conclusions: When using a sensitive MRI definition of SCE incidences are relevantly higher compared to using the “old” definition including the FLAIR-sequence. Technology-associated and procedural characteristics associated with a higher risk of SCE have been identified. Modification of procedural steps of the AF ablation procedure may further reduce the risk of SCE.

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Preoperative T1 magnetic resonance imaging changes carry a poor postoperative prognosis in cervical myelopathy: A retrospective study of 182 patients

Surgical Neurology International ◽

10.25259/sni_1151_2021 ◽

2021 ◽

Vol 12 ◽

pp. 629

Author(s):

Akash Shakya ◽

Ayush Sharma ◽

Vijay Singh ◽

Ajay Jaiswal ◽

Nandan Marathe ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Cervical Myelopathy ◽

Japanese Orthopaedic Association ◽

Postoperative Outcome ◽

Prognostic Indicator ◽

Resonance Imaging ◽

Vas Scores ◽

Group 2 ◽

Group 1

Background: T2 scans are widely used to determine the prognosis for patients undergoing surgery for cervical myelopathy. In this study, we determined whether T1 MR changes in addition to T2 MR changes could have prognostic importance. Methods: This retrospective analysis involved 182 patients undergoing surgery for cervical myelopathy (2017–2020). There were 110 patients in Group 1 (only T2 MR changes) and 72 in Group 2 (both T1 and T2 MR changes). In addition, demographic, visual analog score (VAS), modified Japanese Orthopaedic Association (mJOA) scores, and operative details were recorded at 1 month, 3 months, 6 months, and 1 year postoperatively. Results: Notably, VAS scores were comparable at each point in time and were significantly better than the preoperative scores at 1 year postoperatively. Although mJOA scores were comparable at 1 month in both groups, they were better thereafter for Group 1 patients. Conclusion: The presence of T1 changes on the preoperative magnetic resonance imaging represented a poor prognostic indicator for the postoperative outcome compared to the presence of T2 changes alone.

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