To evaluate the incidence, baseline characteristics, and clinical prognosis of blood-brain barrier (BBB) disruption after endovascular therapy in acute ischemic stroke patients.
A total of 220 ...patients treated with endovascular therapy between April 2007 and October 2011 were identified from a prospective, clinical, thrombolysis registry. All patients underwent a nonenhanced CT scan immediately after treatment. CT scan or MRI was systematically realized at 24 hours to assess intracranial hemorrhage complications. BBB disruption was defined as a hyperdense lesion on the posttreatment CT scan.
BBB disruption was found in 128 patients (58.2%; 95% confidence interval CI, 51.4%-64.9%). Cardioembolic etiology, high admission NIH Stroke Scale score, high blood glucose level, internal carotid artery occlusion, and use of combined endovascular therapy (chemical and mechanical revascularization) were independently associated with BBB disruption. Patients with BBB disruption had lower rates of early major neurologic improvement (8.6% vs 31.5%, p < 0.001), favorable outcome (39.8% vs 61.8%, p = 0.002), and higher rates of 90-day mortality (34.4% vs 14.6%, p = 0.001) and hemorrhagic complications (42.2% vs 8.7%, p < 0.001) than those without BBB disruption. By multivariable analysis, patients with BBB disruption remained with a lower rate of early neurologic improvement (adjusted odds ratio OR, 0.28; 95% CI, 0.11-0.70) and with a higher rate of mortality (adjusted OR, 2.37; 95% CI, 1.06-5.32) and hemorrhagic complications (adjusted OR, 6.38; 95% CI, 2.66-15.28).
BBB disruption has a detrimental effect on outcome and is independently associated with mortality after endovascular therapy. BBB disruption assessment may have a role in prognosis staging in these patients.
The purpose of our prospective study was to assess the presentation of Schmorl's nodes (SN) on magnetic resonance imaging (MRI) and investigate their possible association with demographic and ...clinical findings.
Three hundred and thirty-three patients were prospectively included. Thirteen (3.9%) patients were excluded because of contraindication to MRI and/or Scheuermann's disease. The final study population included 320 patients. T1-weighted and short TI inversion recovery sequences were performed to assess SN prevalence, the vertebral level and their anatomical distribution in vertebra. Medical history was recorded focusing on previous diseases including degenerative, rheumatoid and neoplastic disease, and any existing spinal traumatism. Epidemiological information was also obtained, including age, gender, ethnicity, professional and sporting activity.
The final study population included 320 patients (172 men, 148 women) with a mean age of 54 years±17.5 (SD) (range: 19–87 years). A total of 421 SN were found in 158/320 patients (49.4%). SN were localized in thoracic spine for 48%, in lumbar spine for 46% and cervical spine for 6%. The middle part of the thoracic vertebra was the most affected area (80%), mostly in the middle superior endplate (41%). SN were more frequently observed in manual workers who worked more than 10 years (P<0.0001) and less frequently in patients of the 30–39-year-old age group (P=0.0048). No significant associations were found with gender (P=0.17) and remarkable medical history (P=0.21). SN were less frequently observed in patients with sport activities of 1–5hours/week (P=0.04) and those with an African origin (P<0.0001).
Our study suggests a potential role for ethnical and physical factors in the pathogenesis of SN. Furthers studies are mandatory to evaluate their clinical relevance, especially in patients such as Caucasian manual workers in whom SN have a high prevalence.
Middle cerebral artery (MCA) atherosclerosis is currently diagnosed by indirect angiographic methods. The authors used high-resolution MRI (HR-MRI) to study MCA stenosis in six patients. At the level ...of stenosis, an MCA plaque was clearly delineated and significantly measured vs nonatherosclerotic MCA segments, showing that HR-MRI is an accurate direct imaging method.
The objective of this study was to propose diagnostic reference levels (DRLs) for coronary computed tomography angiography (CCTA), in the context of a large variability in patient radiation dose, and ...the lack of European recommendations. Volume Computed Tomography Dose Index (CTDIvol) and dose-length product (DLP) were collected from 460 CCTAs performed over a 3-month period at eight French hospitals. CCTAs (∼50 per centre) were performed using the routine protocols of the centres, and 64- to 320-detector CT scanners. ECG gating was prospective (n = 199) or retrospective (n = 261). The large gap in dose between these two modes required to propose specific DRLs: 26 and 44 mGy for CTDIvol, and 370 and 970 mGy cm for DLP, respectively. This study confirms the large variability in patient doses during CCTA and underlines the need for the optimisation of cardiac acquisition protocols. Availability of national DRLs should be mandatory in this setting.
To assess the correlation of T2 mapping abnormalities to knee pain location, in young adults with normal standard knee MRI at 3.0 Tesla.
Twenty-three consecutive patients were included prospectively ...from September 2011 to April 2012. Inclusion criteria were age under 50 years old, knee pain without surgical history, and normal knee MRI at 3.0 Tesla (sagittal T1-weighted images, and sagittal, axial and coronal proton-density-weighted images with saturation of fat signal). Ten asymptomatic volunteers were also included as a control group. Patients and controls had a cartilage T2 mapping MRI sequence in addition to the standard MRI protocol. Two musculoskeletal radiologists, blinded to the patient/control condition and pain location, independently reviewed the T2 mapping images. T2 values below 40 ms were considered normal. They rated the number of hyaline cartilage lesions and their grade according to an ICRS-like score (inspired by the International Cartilage Research Society score) in each anatomical compartment (medial and lateral femoro-tibial and anterior patello-femoral joints). In addition, the T2 value of the largest lesion was measured. Patient's pain location was classified in the following categories: anterior, lateral, medial and global. T2 mapping findings were compared to pain location, and retrospectively to the initial standard sequences. Sensitivity and specificity were calculated for MRI with T2 mapping according to pain location for each reader. Kappa coefficient was calculated for inter-reader agreement. We used variance analysis in a linear regression to compare T2 values and ICRS-like classification in each compartment.
Sensitivity of MRI with T2 mapping, according to the symptomatic compartment, was respectively: 78% and 87% for Reader 1 and Reader 2 and specificity was 70% for both readers. Kappa coefficient for T2 mapping abnormalities location and pain location was good, with a calculated value of 0.64. There was no significant correlation between ICRS-like classification and T2 values of lesions (p = 0.18).
Our results suggest that T2 mapping is an interesting MRI sequence for the exploration of young patients knee pain in case of normal MRI with a standard protocol, with a good correlation between pain location and focal prolongations of the cartilage T2 relaxation time.
To prospectively determine whether early first-pass perfusion and delayed-enhancement magnetic resonance (MR) imaging sequences can enable differentiation of acute myocardial infarction (AMI) from ...myocarditis in patients with acute chest pain.
All examinations were performed according to guidelines of the institutional board on medical ethics and clinical investigation and after informed patient consent was obtained. Fifty-five patients with a clinical presentation suggestive but not typical of AMI were examined. At final diagnosis, 31 patients had AMI and 24 had myocarditis. At-rest MR imaging was performed and included first-pass perfusion and delayed-enhancement sequences. Three independent observers read each image data set separately and then in consensus. The main abnormalities included first-pass perfusion defects and delayed highly enhancing areas. The numbers and distributions of involved segments and the transmural extents and the shapes of the highly enhancing areas were noted. For comparisons between the AMI and myocarditis patient groups, the chi2 test was used to assess the locations of the abnormalities and the Mann-Whitney U test was used to assess the numbers of involved segments. The final diagnoses were obtained with coronary angiography as the reference standard for the AMI group and on the basis of normal coronary angiographic findings and the spontaneous resolution of clinical symptoms and wall motion abnormalities for the myocarditis group.
MR imaging patterns were significantly different between the two cardiac disease groups (P < .05). All the patients with AMI had a segmental early subendocardial defect, with corresponding segmental subendocardial or transmural delayed high enhancement in a predominantly anteroseptal or inferior vascular distribution in 28 patients. All patients with AMI had stenosis of at least the infarct-affected coronary artery. All but one of the patients with myocarditis had no early defect and focal or diffuse nonsegmental nonsubendocardial delayed enhancement predominantly in an inferolateral location.
Use of combined early- and late-perfusion MR imaging sequences helps to distinguish AMI from myocarditis.
Purpose: To assess the normal values of fractional anisotropy (FA) and mean diffusivity (MD) of L4, L5 and S1 nerve roots using diffusion tensor imaging (DTI) in healthy volunteers. Materials and ...methods: 37 subjects without previous history of lumbalgia or radiculalgia were prospectively examined: 27 at 1.5T and 10 at 3T MRI. The protocol included standard anatomical sequences and a DTI acquisition. Nerve root fibers were semi automatically extracted from DTI tractography. FA and MD values were measured at 4 key portions along each L4, L5 and S1 nerve roots. Results: At 1.5T MRI, FA and MD were 0.221 ± 0.011 and 460.9 ± 35.5 mm2.s-1 respectively; at 3T MRI, FA and MD were 0.216 ± 0.01 and 480.1 ± 36.1 mm2.s-1 respectively, which may be considered as normal values for mobile lumbar spine nerve roots, independently of intersomatic space level (p = 0.06) and nerve root portion (p = 0.08) or magnetic field (p = 0.06). Conclusion: Normal FA and MD values can be measured along lumbar mobile spine nerve roots in healthy subjects. These values were not dependent on intersomatic space level, side or anatomical portion of the nerve root or magnetic field.
To measure the fractional anisotropy (FA) and the mean diffusivity (MD) values of L4, L5 and S1 nerve roots using diffusion tensor imaging (DTI) and to correlate them with four different clinical ...patterns.
Fifty-six human participants were prospectively included and divided between four groups: healthy subjects, patients with clinical symptomatic nerve root pain with and without anatomical discoradicular conflict and patients with incidental anatomical discoradicular conflict seen on magnetic resonance imaging (MRI). MRI protocol included anatomical sequences (sagittal T1- and T2-weighted, axial T2-weighted) and a 25 directions DTI sequence. FA and MD values were measured in consensus by two readers and compared between the four groups.
Mean FA and MD values were significantly different for patients with clinically symptomatic nerve root pain (n=27) both with (n=16) (FA=0.187±0.015; MD=510±40) and without (n=11) (FA=0.193±0.011; MD=490±30.5) anatomical discoradicular conflict compared to healthy subjects (n=29) (FA=0.221±0.011; MD=460.9±35.5) including 2 subjects with incidental anatomical discoradicular conflict (FA=0.211±0.013; MD=450.8±41.2) on MRI (P=0.003).
Measurement of FA and MD values of L4, L5 and S1 nerve roots using DTI could be useful in lumbar nerve root pain assessment. Further studies with different image processing methods are needed.
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