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Sommaires des Revues - AJNR

American Journal of Neuroradiology current issue


American Journal of Neuroradiology (AJNR) RSS feed -- current issue. AJNR (hwmaint.ajnr.org ) is the premier journal for diagnostic and interventional neuroradiology, publishing more than 200 fully reviewed scientific papers, case reports, and technical notes per year.


American Society of Functional Neuroradiology-Recommended fMRI Paradigm Algorithms for Presurgical Language Assessment [FUNCTIONAL]  Voir?

INTRODUCTION:

Functional MR imaging is increasingly being used for presurgical language assessment in the treatment of patients with brain tumors, epilepsy, vascular malformations, and other conditions. The inherent complexity of fMRI, which includes numerous processing steps and selective analyses, is compounded by institution-unique approaches to patient training, paradigm choice, and an eclectic array of postprocessing options from various vendors. Consequently, institutions perform fMRI in such markedly different manners that data sharing, comparison, and generalization of results are difficult. The American Society of Functional Neuroradiology proposes widespread adoption of common fMRI language paradigms as the first step in countering this lost opportunity to advance our knowledge and improve patient care.

LANGUAGE PARADIGM REVIEW PROCESS:

A taskforce of American Society of Functional Neuroradiology members from multiple institutions used a broad literature review, member polls, and expert opinion to converge on 2 sets of standard language paradigms that strike a balance between ease of application and clinical usefulness.

ASFNR RECOMMENDATIONS:

The taskforce generated an adult language paradigm algorithm for presurgical language assessment including the following tasks: Sentence Completion, Silent Word Generation, Rhyming, Object Naming, and/or Passive Story Listening. The pediatric algorithm includes the following tasks: Sentence Completion, Rhyming, Antonym Generation, or Passive Story Listening.

DISCUSSION:

Convergence of fMRI language paradigms across institutions offers the first step in providing a "Rosetta Stone" that provides a common reference point with which to compare and contrast the usefulness and reliability of fMRI data. From this common language task battery, future refinements and improvements are anticipated, particularly as objective measures of reliability become available. Some commonality of practice is a necessary first step to develop a foundation on which to improve the clinical utility of this field.

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Torgny Greitz, MD, PhD, FACR, Professor of Neuroradiology, Emeritus [other]  Voir?

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Spinal Cord, Spinal Root, and Brain MRI Abnormalities in Congenital Zika Syndrome [LETTERS]  Voir?

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High-Resolution Hybrid Imaging Could Improve Cordotomy Lesions and Outcomes [LETTERS]  Voir?

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The Concept of "Number Needed to Image" [LETTERS]  Voir?

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Coregistration and Fusion: An Easy and Reliable Method for Identifying Cranial Nerve IV on MRI [LETTERS]  Voir?

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Reply: [LETTERS]  Voir?

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Minor Stroke and Thrombolysis: What Is in the Pipeline? [LETTERS]  Voir?

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Reply: [LETTERS]  Voir?

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ERRATUM [ERRATA]  Voir?

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[other]  Voir?

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Neuroimaging Changes in Menkes Disease, Part 1 [PEDIATRICS]  Voir?

SUMMARY:

Menkes disease is a rare multisystem X-linked disorder of copper metabolism. Despite an early, severe, and progressive neurologic involvement, our knowledge of brain involvement remains unsatisfactory. The first part of this retrospective and review MR imaging study aims to define the frequency rate, timing, imaging features, and evolution of intracranial vascular and white matter changes. According to our analysis, striking but also poorly evolutive vascular abnormalities characterize the very early phases of disease. After the first months, myelination delay becomes evident, often in association with protean focal white matter lesions, some of which reveal an age-specific brain vulnerability. In later phases of the disease, concomitant progressive neurodegeneration might hinder the myelination progression. The currently enriched knowledge of neuroradiologic finding evolution provides valuable clues for early diagnosis, identifies possible MR imaging biomarkers of new treatment efficacy, and improves our comprehension of possible mechanisms of brain injury in Menkes disease.

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Neuroimaging Changes in Menkes Disease, Part 2 [PEDIATRICS]  Voir?

SUMMARY:

This is the second part of a retrospective and review MR imaging study aiming to define the frequency rate, timing, imaging features, and evolution of gray matter changes in Menkes disease, a rare multisystem X-linked disorder of copper metabolism characterized by early, severe, and progressive neurologic involvement. According to our analysis, neurodegenerative changes and focal basal ganglia lesions already appear in the early phases of the disease. Subdural collections are less common than generally thought; however, their presence remains important because they might challenge the differential diagnosis with child abuse and might precipitate the clinical deterioration. Anecdotal findings in our large sample seem to provide interesting clues about the protean mechanisms of brain injury in this rare disease and further highlight the broad spectrum of MR imaging findings that might be expected while imaging a child with the suspicion of or a known diagnosis of Menkes disease.

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Maximizing the Tweet Engagement Rate in Academia: Analysis of the AJNR Twitter Feed [research-article]  Voir?

SUMMARY:

The use of social media by medical professionals and organizations is increasing, with Twitter receiving the most attention. User engagement is an important goal of social media activity, and engagement metrics represent a viable gauge of value in social media. No thorough analysis of tweet characteristics that increase academic user engagement has yet been published. In this study, the authors analyzed the American Journal of Neuroradiology Twitter feed to determine the tweet characteristics that were associated with higher engagement rates.

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Spinal and Paraspinal Plexiform Neurofibromas in Patients with Neurofibromatosis Type 1: A Novel Scoring System for Radiological-Clinical Correlation [SPINE]  Voir?

BACKGROUND AND PURPOSE:

Neurofibromatosis type 1 is a common tumor predisposition syndrome. The aim of this study was to characterize the radiologic presentation of patients with neurofibromatosis type 1 with widespread spinal disease and to correlate it to clinical presentation and outcome.

MATERIALS AND METHODS:

We conducted a historical cohort study of adult patients with neurofibromatosis type 1 with spinal involvement. Longitudinal clinical evaluation included pain and neurologic deficits. Radiologically, spinal involvement was classified according to a novel classification system, and a radiologic risk score was calculated.

RESULTS:

Two hundred fifty-seven adult patients with neurofibromatosis type 1 are followed in our center. Thirty-four of these patients qualified for inclusion in this study. Three independent factors were found to be associated with increased risk for neurologic deficit: 1) bilateral tumors at the same level in the cervical region that approximated each other, 2) paraspinal tumors at the lumbar region, and 3) intradural lesions. On the basis of these factors, we calculated a combined risk score for neurologic deficits for each patient. We found a clear correlation between patient status and the calculated radiologic risk score. Patients with neurologic deficits were found to have a higher risk score (9 ± 8.3) than patients without neurologic deficits (2.5 ± 2.9, P < .05). Patients who progressed during the follow-up period had significantly higher scores at presentation than patients with stable conditions (9.9 ± 8.73 versus 3.9 ± 5.3, respectively; P < .05).

CONCLUSIONS:

In this series, neurologic deficit is correlated with tumor burden and subtype. We found no direct correlation with tumor burden and pain. Our novel radiologic classification scoring system may be used to predict increased risk for neurologic morbidity.

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3D Pseudocontinuous Arterial Spin-Labeling MR Imaging in the Preoperative Evaluation of Gliomas [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Previous studies showed conflicting results concerning the value of CBF maps obtained from arterial spin-labeling MR imaging in grading gliomas. This study was performed to investigate the effectiveness of CBF maps derived from 3D pseudocontinuous arterial spin-labeling in preoperatively assessing the grade, cellular proliferation, and prognosis of gliomas.

MATERIALS AND METHODS:

Fifty-eight patients with pathologically confirmed gliomas underwent preoperative 3D pseudocontinuous arterial spin-labeling. The receiver operating characteristic curves for parameters to distinguish high-grade gliomas from low-grade gliomas were generated. Pearson correlation analysis was used to assess the correlation among parameters. Survival analysis was conducted with Cox regression.

RESULTS:

Both maximum CBF and maximum relative CBF were significantly higher in high-grade gliomas than in low-grade gliomas (P < .001). The areas under the curve for maximum CBF and maximum relative CBF in distinguishing high-grade gliomas from low-grade gliomas were 0.828 and 0.863, respectively. Both maximum CBF and maximum relative CBF had no correlation with the Ki-67 index in all subjects and had a moderate negative correlation with the Ki-67 index in glioblastomas (r = –0.475, –0.534, respectively). After adjustment for age, a higher maximum CBF (P = .008) and higher maximum relative CBF (P = .005) were associated with worse progression-free survival in gliomas, while a higher maximum relative CBF (P = .033) was associated with better overall survival in glioblastomas.

CONCLUSIONS:

3D pseudocontinuous arterial spin-labeling–derived CBF maps are effective in preoperative evaluation of gliomas. Although gliomas with a higher blood flow are more malignant, glioblastomas with a lower blood flow are likely to be more aggressive.

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Diagnostic Accuracy of Neuroimaging to Delineate Diffuse Gliomas within the Brain: A Meta-Analysis [ADULT BRAIN]  Voir?

BACKGROUND:

Brain imaging in diffuse glioma is used for diagnosis, treatment planning, and follow-up.

PURPOSE:

In this meta-analysis, we address the diagnostic accuracy of imaging to delineate diffuse glioma.

DATA SOURCES:

We systematically searched studies of adults with diffuse gliomas and correlation of imaging with histopathology.

STUDY SELECTION:

Study inclusion was based on quality criteria. Individual patient data were used, if available.

DATA ANALYSIS:

A hierarchic summary receiver operating characteristic method was applied. Low- and high-grade gliomas were analyzed in subgroups.

DATA SYNTHESIS:

Sixty-one studies described 3532 samples in 1309 patients. The mean Standard for Reporting of Diagnostic Accuracy score (13/25) indicated suboptimal reporting quality. For diffuse gliomas as a whole, the diagnostic accuracy was best with T2-weighted imaging, measured as area under the curve, false-positive rate, true-positive rate, and diagnostic odds ratio of 95.6%, 3.3%, 82%, and 152. For low-grade gliomas, the diagnostic accuracy of T2-weighted imaging as a reference was 89.0%, 0.4%, 44.7%, and 205; and for high-grade gliomas, with T1-weighted gadolinium-enhanced MR imaging as a reference, it was 80.7%, 16.8%, 73.3%, and 14.8. In high-grade gliomas, MR spectroscopy (85.7%, 35.0%, 85.7%, and 12.4) and 11C methionine–PET (85.1%, 38.7%, 93.7%, and 26.6) performed better than the reference imaging.

LIMITATIONS:

True-negative samples were underrepresented in these data, so false-positive rates are probably less reliable than true-positive rates. Multimodality imaging data were unavailable.

CONCLUSIONS:

The diagnostic accuracy of commonly used imaging is better for delineation of low-grade gliomas than high-grade gliomas on the basis of limited evidence. Improvement is indicated from advanced techniques, such as MR spectroscopy and PET.

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Imaging Biomarkers for Adult Medulloblastomas: Genetic Entities May Be Identified by Their MR Imaging Radiophenotype [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

The occurrence of medulloblastomas in adults is rare; nevertheless, these tumors can be subdivided into genetic and histologic entities each having distinct prognoses. This study aimed to identify MR imaging biomarkers to classify these entities and to uncover differences in MR imaging biomarkers identified in pediatric medulloblastomas.

MATERIALS AND METHODS:

Eligible preoperative MRIs from 28 patients (11 women; 22–53 years of age) of the Multicenter Pilot-study for the Therapy of Medulloblastoma of Adults (NOA-7) cohort were assessed by 3 experienced neuroradiologists. Lesions and perifocal edema were volumetrized and multiparametrically evaluated for classic morphologic characteristics, location, hydrocephalus, and Chang criteria. To identify MR imaging biomarkers, we correlated genetic entities sonic hedgehog (SHH) TP53 wild type, wingless (WNT), and non-WNT/non-SHH medulloblastomas (in adults, Group 4), and histologic entities were correlated with the imaging criteria. These MR imaging biomarkers were compared with corresponding data from a pediatric study.

RESULTS:

There were 19 SHH TP53 wild type (69%), 4 WNT-activated (14%), and 5 Group 4 (17%) medulloblastomas. Six potential MR imaging biomarkers were identified, 3 of which, hydrocephalus (P = .03), intraventricular macrometastases (P = .02), and hemorrhage (P = .04), when combined, could identify WNT medulloblastoma with 100% sensitivity and 88.3% specificity (95% CI, 39.8%–100.0% and 62.6%–95.3%). WNT-activated nuclear β-catenin accumulating medulloblastomas were smaller than the other entities (95% CI, 5.2–22.3 cm3 versus 35.1–47.6 cm3; P = .03). Hemorrhage was exclusively present in non-WNT/non-SHH medulloblastomas (P = .04; n = 2/5). MR imaging biomarkers were all discordant from those identified in the pediatric cohort. Desmoplastic/nodular medulloblastomas were more rarely in contact with the fourth ventricle (4/15 versus 7/13; P = .04).

CONCLUSIONS:

MR imaging biomarkers can help distinguish histologic and genetic medulloblastoma entities in adults and appear to be different from those identified in children.

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Multinodular and Vacuolating Neuronal Tumor of the Cerebrum: A New "Leave Me Alone" Lesion with a Characteristic Imaging Pattern [ADULT BRAIN]  Voir?

SUMMARY:

Multinodular and vacuolating neuronal tumor of the cerebrum is a recently reported benign, mixed glial neuronal lesion that is included in the 2016 updated World Health Organization classification of brain neoplasms as a unique cytoarchitectural pattern of gangliocytoma. We report 33 cases of presumed multinodular and vacuolating neuronal tumor of the cerebrum that exhibit a remarkably similar pattern of imaging findings consisting of a subcortical cluster of nodular lesions located on the inner surface of an otherwise normal-appearing cortex, principally within the deep cortical ribbon and superficial subcortical white matter, which is hyperintense on FLAIR. Only 4 of our cases are biopsy-proven because most were asymptomatic and incidentally discovered. The remaining were followed for a minimum of 24 months (mean, 3 years) without interval change. We demonstrate that these are benign, nonaggressive lesions that do not require biopsy in asymptomatic patients and behave more like a malformative process than a true neoplasm.

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Age, Sex, and Racial Differences in Neuroimaging Use in Acute Stroke: A Population-Based Study [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Limited information is available regarding differences in neuroimaging use for acute stroke work-up. Our objective was to assess whether race, sex, or age differences exist in neuroimaging use and whether these differences depend on the care center type in a population-based study.

MATERIALS AND METHODS:

Patients with stroke (ischemic and hemorrhagic) and transient ischemic attack were identified in a metropolitan, biracial population using the Greater Cincinnati/Northern Kentucky Stroke Study in 2005 and 2010. Multivariable regression was used to determine the odds of advanced imaging use (CT angiography/MR imaging/MR angiography) for race, sex, and age.

RESULTS:

In 2005 and 2010, there were 3471 and 3431 stroke/TIA events, respectively. If one adjusted for covariates, the odds of advanced imaging were higher for younger (55 years or younger) compared with older patients, blacks compared with whites, and patients presenting to an academic center and those seen by a stroke team or neurologist. The observed association between race and advanced imaging depended on age; in the older age group, blacks had higher odds of advanced imaging compared with whites (odds ratio, 1.34; 95% CI, 1.12–1.61; P < .01), and in the younger group, the association between race and advanced imaging was not statistically significant. Age by race interaction persisted in the academic center subgroup (P < .01), but not in the nonacademic center subgroup (P = .58). No significant association was found between sex and advanced imaging.

CONCLUSIONS:

Within a large, biracial stroke/TIA population, there is variation in the use of advanced neuroimaging by age and race, depending on the care center type.

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Improved Detection of Anterior Circulation Occlusions: The "Delayed Vessel Sign" on Multiphase CT Angiography [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Multiphase CTA, a technique to dynamically assess the vasculature in acute ischemic stroke, was primarily developed to evaluate collateral filling. We have observed that it is also useful in identifying distal anterior circulation occlusions due to delayed anterior circulation opacification on multiphase CTA, an observation we term the "delayed vessel sign." We aimed to determine the usefulness of this sign by comparing multiphase CTA with single-phase CTA.

MATERIALS AND METHODS:

All 23 distal anterior circulation occlusions during a 2-year period were included. Ten M1-segment occlusions and 10 cases without a vessel occlusion were also included. All patients had follow-up imaging confirming the diagnosis. Initially, the noncontrast CT and first phase of the multiphase CTA study for each patient were blindly evaluated (2 neuroradiologists, 2 radiology trainees) for an anterior circulation occlusion. Readers' confidence, speed, and sensitivity of detection were recorded. Readers were then educated on the "delayed vessel sign," and each multiphase CTA study was re-examined for a vessel occlusion after at least 14 days.

RESULTS:

There was significant improvement in the sensitivity of detection of distal anterior circulation vessel occlusions (P < .001), overall confidence (P < .001), and time taken to interpret (P < .001) with multiphase CTA compared with single-phase CTA. Readers preferred MIP images compared with source images in >90% of cases.

CONCLUSIONS:

The delayed vessel sign is a reliable indicator of anterior circulation vessel occlusion, particularly in cases involving distal branches. Assessment of the later phases of multiphase CTA for the delayed vessel sign leads to a significant improvement in the speed and confidence of interpretation, compared with single-phase CTA.

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Concordance of Time-of-Flight MRA and Digital Subtraction Angiography in Adult Primary Central Nervous System Vasculitis [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

3D-TOF-MRA and DSA are 2 available tools to demonstrate neurovascular involvement in primary central nervous system vasculitis. We aimed to compare the diagnostic concordance of vessel imaging using 3D-TOF-MRA and DSA in patients with primary central nervous system vasculitis.

MATERIALS AND METHODS:

We retrospectively identified all patients included in the French primary central nervous system vasculitis cohort of 85 patients who underwent, at baseline, both intracranial 3D-TOF-MRA and DSA in an interval of no more than 2 weeks and before treatment initiation. Two neuroradiologists independently reviewed all 3D-TOF-MRA and DSA imaging. Brain vasculature was divided into 25 arterial segments. Concordance between 3D-TOF-MRA and DSA for the identification of arterial stenosis was assessed by the Cohen Index.

RESULTS:

Thirty-one patients met the inclusion criteria, including 20 imaged with a 1.5T MR unit and 11 with a 3T MR unit. Among the 25 patients (81%) with abnormal DSA findings, 24 demonstrated abnormal 3D-TOF-MRA findings, whereas all 6 remaining patients with normal DSA findings had normal 3D-TOF-MRA findings. In the per-segment analysis, concordance between 1.5T 3D-TOF-MRA and DSA was 0.82 (95% CI, 0.75–0.93), and between 3T 3D-TOF-MRA and DSA, it was 0.87 (95% CI, 0.78–0.91).

CONCLUSIONS:

3D-TOF-MRA shows a high concordance with DSA in diagnostic performance when analyzing brain vasculature in patients with primary central nervous system vasculitis. In patients with negative 3T 3D-TOF-MRA findings, the added diagnostic value of DSA is limited.

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In Vivo Imaging of Venous Side Cerebral Small-Vessel Disease in Older Adults: An MRI Method at 7T [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Traditional neuroimaging markers of small-vessel disease focus on late-stage changes. We aimed to adapt a method of venular assessment at 7T for use in older adults. We hypothesized that poorer venular morphologic characteristics would be related to other small-vessel disease neuroimaging markers and a higher prevalence of small-vessel disease–Alzheimer disease risk factors.

MATERIALS AND METHODS:

Venules were identified in periventricular ROIs on SWI and defined as tortuous or straight. The tortuosity ratio was defined as total tortuous venular length divided by total straight venular length. White matter hyperintensity burden (visually rated from 0 to 3) and the number of microbleeds (0, 1, >1) were determined. Differences in tortuous and straight venular lengths were evaluated. Relationships with demographic variables, allele producing the e4 type of apolipoprotein E (APOE4), growth factors, pulse pressure, physical activity, and Modified Mini-Mental State Examination were assessed via Spearman correlations.

RESULTS:

Participants had 42% more tortuous venular tissue than straight (median, 1.42; 95% CI, 1.13–1.62). APOE4 presence was associated with a greater tortuosity ratio ( = 0.454, P = .001), and these results were robust to adjustment for confounders and multiple comparisons. Associations of the tortuosity ratio with sex and vascular endothelial growth factor did not survive adjustment. Associations of the tortuosity ratio with other variables of interest were not significant.

CONCLUSIONS:

Morphologic measures of venules at 7T could be useful biomarkers of the early stages of small-vessel disease and Alzheimer disease. Longitudinal studies should examine the impact of apolipoprotein E and vascular endothelial growth factor on the risk of venular damage.

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Basal Ganglia T1 Hyperintensity in Hereditary Hemorrhagic Telangiectasia [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

The implications of basal ganglia T1 hyperintensity remain unclear in patients with hereditary hemorrhagic telangiectasia. This study was performed to assess the prevalence of this imaging finding in a large cohort of patients with hereditary hemorrhagic telangiectasia and to identify any association between this phenomenon and other disease manifestations.

MATERIALS AND METHODS:

In this retrospective study, we identified all patients at our institution diagnosed with definite hereditary hemorrhagic telangiectasia from 2001 to 2017. Patients who did not undergo brain MR imaging were excluded. Patient demographics, laboratory results, and hereditary hemorrhagic telangiectasia disease characteristics were noted. Basal ganglia hyperintensity was evaluated both qualitatively and quantitatively relative to the signal intensity in the ipsilateral thalami. Statistical analysis was performed with commercially available software.

RESULTS:

A total of 312 patients (41% men, 59% women; mean age, 51 ± 18 years) with definite hereditary hemorrhagic telangiectasia were identified. Basal ganglia T1 hyperintensity was present in 23.4% of patients and demonstrated a statistically significant association with older age (P < .001), increased hepatic AVMs (P < .001), high cardiac output state (P < .001), hepatic failure (P = .01), elevated peak serum alkaline phosphatase level (P = .03), and increased total bilirubin count (P = .03). There was no significant association with sex, hereditary hemorrhagic telangiectasia genetic mutation status, parkinsonism, or serum transaminase levels.

CONCLUSIONS:

Basal ganglia T1 hyperintensity occurs in >23% of patients with hereditary hemorrhagic telangiectasia and is associated with hepatic vascular malformations, hepatic dysfunction, and elevated cardiac output. The presence of this finding on screening MR imaging in patients with hereditary hemorrhagic telangiectasia should prompt further evaluation for visceral lesions causing arteriovenous shunting.

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Analysis of White Matter Damage in Patients with Multiple Sclerosis via a Novel In Vivo MR Method for Measuring Myelin, Axons, and G-Ratio [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Myelin and axon volume fractions can now be estimated via MR imaging in vivo, as can the g-ratio, which equals the ratio of the inner to the outer diameter of a nerve fiber. The purpose of this study was to evaluate WM damage in patients with MS via this novel MR imaging technique.

MATERIALS AND METHODS:

Twenty patients with relapsing-remitting MS with a combined total of 149 chronic plaques were analyzed. Myelin volume fraction was calculated based on simultaneous tissue relaxometry. Intracellular and CSF compartment volume fractions were quantified via neurite orientation dispersion and density imaging. Axon volume fraction and g-ratio were calculated by combining these measurements. Myelin and axon volume fractions and g-ratio were measured in plaques, periplaque WM, and normal-appearing WM.

RESULTS:

All metrics differed significantly across the 3 groups (P < .001, except P = .027 for g-ratio between periplaque WM and normal-appearing WM). Those in plaques differed most from those in normal-appearing WM. The percentage changes in plaque and periplaque WM metrics relative to normal-appearing WM were significantly larger in absolute value for myelin volume fraction than for axon volume fraction and g-ratio (P < .001, except P = .033 in periplaque WM relative to normal-appearing WM for comparison between myelin and axon volume fraction).

CONCLUSIONS:

In this in vivo MR imaging study, the myelin of WM was more damaged than axons in plaques and periplaque WM of patients with MS. Myelin and axon volume fractions and g-ratio may potentially be useful for evaluating WM damage in patients with MS.

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Pre- and Postcontrast 3D Double Inversion Recovery Sequence in Multiple Sclerosis: A Simple and Effective MR Imaging Protocol [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

The double inversion recovery sequence is known to be very sensitive and specific for MS-related lesions. Our aim was to compare the sensitivity of pre- and postcontrast images of 3D double inversion recovery and conventional 3D T1-weighted images for the detection of contrast-enhancing MS-related lesions in the brain to analyze whether double inversion recovery could be as effective as T1WI.

MATERIALS AND METHODS:

A postcontrast 3D double inversion recovery sequence was acquired in addition to the standard MR imaging protocol at 3T, including pre- and postcontrast 3D T1WI sequences as well as precontrast double inversion recovery of 45 consecutive patients with MS or clinically isolated syndrome between June and December 2013. Two neuroradiologists independently assessed precontrast, postcontrast, and subtraction images of double inversion recovery as well as T1WI to count the number of contrast-enhancing lesions. Afterward, a consensus reading was performed. Lin concordance was calculated between both radiologists, and differences in lesion detectability were assessed with the Student t test. Additionally, the contrast-to-noise ratio was calculated.

RESULTS:

Significantly more contrast-enhancing lesions could be detected with double inversion recovery compared with T1WI (16%, 214 versus 185, P = .007). The concordance between both radiologists was almost perfect (c = 0.94 for T1WI and c = 0.98 for double inversion recovery, respectively). The contrast-to-noise ratio was significantly higher in double inversion recovery subtraction images compared with T1-weighted subtraction images (double inversion recovery, 14.3 ± 5.5; T1WI, 6.3 ± 7.1; P < .001).

CONCLUSIONS:

Pre- and postcontrast double inversion recovery enables better detection of contrast-enhancing lesions in MS in the brain compared with T1WI and may be considered an alternative to the standard MR imaging protocol.

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Dual-Energy CT in Enhancing Subdural Effusions that Masquerade as Subdural Hematomas: Diagnosis with Virtual High-Monochromatic (190-keV) Images [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Extravasation of iodinated contrast into subdural space following contrast-enhanced radiographic studies results in hyperdense subdural effusions, which can be mistaken as acute subdural hematomas on follow-up noncontrast head CTs. Our aim was to identify the factors associated with contrast-enhancing subdural effusion, characterize diffusion and washout kinetics of iodine in enhancing subdural effusion, and assess the utility of dual-energy CT in differentiating enhancing subdural effusion from subdural hematoma.

MATERIALS AND METHODS:

We retrospectively analyzed follow-up head dual-energy CT studies in 423 patients with polytrauma who had undergone contrast-enhanced whole-body CT. Twenty-four patients with enhancing subdural effusion composed the study group, and 24 randomly selected patients with subdural hematoma were enrolled in the comparison group. Postprocessing with syngo.via was performed to determine the diffusion and washout kinetics of iodine. The sensitivity and specificity of dual-energy CT for the diagnosis of enhancing subdural effusion were determined with 120-kV, virtual monochromatic energy (190-keV) and virtual noncontrast images.

RESULTS:

Patients with enhancing subdural effusion were significantly older (mean, 69 years; 95% CI, 60–78 years; P < .001) and had a higher incidence of intracranial hemorrhage (P = .001). Peak iodine concentration in enhancing subdural effusions was reached within the first 8 hours of contrast administration with a mean of 0.98 mg/mL (95% CI, 0.81–1.13 mg/mL), and complete washout was achieved at 38 hours. For the presence of a hyperdense subdural collection on 120-kV images with a loss of hyperattenuation on 190-keV and virtual noncontrast images, when considered as a true-positive for enhancing subdural effusion, the sensitivity was 100% (95% CI, 85.75%–100%) and the specificity was 91.67% (95% CI, 73%–99%).

CONCLUSIONS:

Dual-energy CT has a high sensitivity and specificity in differentiating enhancing subdural effusion from subdural hematoma. Hence, dual-energy CT has a potential to obviate follow-up studies.

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Assessment of Iron Deposition in the Brain in Frontotemporal Dementia and Its Correlation with Behavioral Traits [ADULT BRAIN]  Voir?

BACKGROUND AND PURPOSE:

Brain iron deposition has been implicated as a major culprit in the pathophysiology of neurodegeneration. However, the quantitative assessment of iron in behavioral variant frontotemporal dementia and primary progressive aphasia brains has not been performed, to our knowledge. The aim of our study was to investigate the characteristic iron levels in the frontotemporal dementia subtypes using susceptibility-weighted imaging and report its association with behavioral profiles.

MATERIALS AND METHODS:

This prospective study included 46 patients with frontotemporal dementia (34 with behavioral variant frontotemporal dementia and 12 with primary progressive aphasia) and 34 age-matched healthy controls. We performed behavioral and neuropsychological assessment in all the subjects. The quantitative iron load was determined on SWI in the superior frontal gyrus and temporal pole, precentral gyrus, basal ganglia, anterior cingulate, frontal white matter, head and body of the hippocampus, red nucleus, substantia nigra, insula, and dentate nucleus. A linear regression analysis was performed to correlate iron content and behavioral scores in patients.

RESULTS:

The iron content of the bilateral superior frontal and temporal gyri, anterior cingulate, putamen, right hemispheric precentral gyrus, insula, hippocampus, and red nucleus was higher in patients with behavioral variant frontotemporal dementia than in controls. Patients with primary progressive aphasia had increased iron levels in the left superior temporal gyrus. In addition, right superior frontal gyrus iron deposition discriminated behavioral variant frontotemporal dementia from primary progressive aphasia. A strong positive association was found between apathy and iron content in the superior frontal gyrus and disinhibition and iron content in the putamen.

CONCLUSIONS:

Quantitative assessment of iron deposition with SWI may serve as a new biomarker in the diagnostic work-up of frontotemporal dementia and help distinguish frontotemporal dementia subtypes.

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Multicenter Experience with FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms in Small Arteries [INTERVENTIONAL]  Voir?

BACKGROUND AND PURPOSE:

Flow diverters are emerging as an endovascular treatment alternative for proximally located intracranial aneurysms. However, treatment of aneurysms at and beyond the circle of Willis is not well-established. We assessed the clinical safety and efficacy of the Flow Re-Direction Endoluminal Device Jr (FRED Jr) dedicated to small-vessel diameters between 2.0 and 3.0 mm.

MATERIALS AND METHODS:

This was a multicenter observational clinical study of 42 patients with 47 aneurysms treated by a flow-direction technique with the FRED Jr. The primary end point for clinical safety was the absence of death, major or minor stroke, and TIA. The primary end point for treatment efficacy was complete and near-complete occlusion according to the O'Kelly-Marotta grading scale at follow-up after 1, 6, and 12 months.

RESULTS:

The FRED Jr deployment was technically successful in all cases. In 39/42 (93%) patients, the primary safety end point was reached; in the 3 remaining patients, 1 disabling ischemic stroke, 1 minor stroke with complete recovery at discharge, and 1 TIA were observed. Two asymptomatic, completely reversible side-branch occlusions occurred. Angiographic (DSA or flat panel CT) and clinical follow-up were available after 1 month in 41/47 (87%), 6 months in 27/47 (57%), and 12 months in 11/47 (23%) aneurysms. The primary efficacy end point was reached at 1 month in 27/41 (66%), at 6 months in 21/27 (78%), and at 12 months in 11/11 (100%) aneurysms.

CONCLUSIONS:

Deployment of the FRED Jr is safe and effective in the treatment of intracranial aneurysms located in small vessels.

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Clinical Impact of Flat Panel Volume CT Angiography in Evaluating the Accurate Intraoperative Deployment of Flow-Diverter Stents [INTERVENTIONAL]  Voir?

BACKGROUND AND PURPOSE:

The deployment of flow-diverter stents may be difficult to analyse on regular DSA. The purpose of our study was to investigate the clinical impact of stent-dedicated flat panel volume CT angiography to evaluate intraoperatively the satisfactory deployment of flow-diverter stents.

MATERIALS AND METHODS:

From January 2009 to April 2015, 83 consecutive patients (mean age, 51 years; 62 women) were treated in our institution with flow-diverter stents. Eighty-seven aneurysms (82 unruptured, 5 ruptured; 77 anterior, 10 posterior circulation) were treated in these 83 patients (4 patients had 2 aneurysms, both treated by means of flow-diverter stents). One patient was treated for a traumatic carotid cavernous fistula. In 80% of the cases (68/85) a flat panel volume CT angiography was performed in the angiographic suite just after the flow-diverter stent deployment. Stent visualization was assessed by 2 independent reviewers. The clinical impact of stent malapposition was evaluated.

RESULTS:

Flow-diverter stent visualization was satisfactory in 73.5% of the cases. In 2 cases (2.9%) the flat panel volume CT angiography prompted the operator to perform an additional intrastent angioplasty for a condition that was previously underestimated. Four patients (4.7%) experienced acute thromboembolic complications; 3 others had delayed thromboembolic complications. Only 1 of these patients had thromboembolic complications (acute or delayed) related to stent misdeployment, which was easily managed intraoperatively with no clinical consequence.

CONCLUSIONS:

Flat panel volume CT angiography is an interesting tool to depict flow-diverter stent misdeployment and may encourage the operator to perform intrastent angioplasty (2.9% of the cases in our experience) to reduce the risks of thromboembolic complications.

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Packing Density Necessary to Reach a High Complete Occlusion Rate in Circumferential Unruptured Intracranial Aneurysms Treated with Stent-Assisted Coil Embolization [INTERVENTIONAL]  Voir?

BACKGROUND AND PURPOSE:

This study is a homogeneous series of circumferential unruptured intracranial aneurysms with large necks treated with stent-assisted coil embolization. Our purpose was to demonstrate which value of packing density is required to produce a durable occlusion.

MATERIALS AND METHODS:

We retrospectively evaluated all patients with unruptured intracranial aneurysms who were treated with stent-assisted coil embolization having late angiographic control between 2004 and 2014, in a single large cerebrovascular referral center. To calculate the packing density, aneurysm volume, and coil volume, we used an on-line system.

RESULTS:

In 49 circumferential unruptured intracranial aneurysms treated with stent-assisted coil embolization, 38.7% (n = 19) had complete occlusion in the immediate control. Of those with incomplete occlusion, 80% (n = 24) progressed to complete occlusion in the late angiographic follow-up. At late angiographic control, 87.7% (n = 43) of aneurysms were completely occluded. All aneurysms with a packing density of ≥19% were completely occluded. Packing density was the only statistically significant predictor of complete occlusion. None of the aneurysms with complete occlusion at immediate control or at late angiographic control had recurrence.

CONCLUSIONS:

In circumferential aneurysms treated with stent-assisted coil embolization, packing density is the main predictor of complete occlusion. In this type of aneurysm, a packing density of ≥19% was enough to reach complete occlusion; knowing this is important to avoid higher packing densities that have more risk.

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The Use and Utility of Aspiration Thrombectomy in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis [INTERVENTIONAL]  Voir?

BACKGROUND:

Thrombectomy trials are often specifically interpreted as evidence for the effectiveness of stent retrievers. The effectiveness of other thrombectomy techniques such as aspiration thrombectomy should be validated through further investigation and review.

PURPOSE:

To evaluate published treatment times and clinical outcomes in patients treated with aspiration thrombectomy or ADAPT (A Direct Aspiration, First Pass Technique) for acute ischemic stroke.

DATA SOURCES:

A systematic literature review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE, Scopus, and the Cochrane trial register were searched on November 8, 2016.

STUDY SELECTION:

Twenty studies (n = 1523 patients) were included in this review and meta-analysis. One of these studies was prospective, and the rest were retrospective.

DATA ANALYSIS:

Meta-analysis was performed by using a random effects model. Data and publication bias were visualized with forest plots and funnel plots.

DATA SYNTHESIS:

Five studies investigated aspiration thrombectomy only, and 16 studies investigated ADAPT. Of the 16 studies on ADAPT, the rate of successful recanalization (TICI 2b/3) was 89.3% (95% CI, 85.4%–92.3%). The proportion of patients with good clinical outcome (90-day mRS ≤2) was 52.7% (95% CI, 48.0%–57.4%).

LIMITATIONS:

Studies on ADAPT were retrospective, and there was heterogeneity between studies for successful recanalization (P < .001) and good clinical outcome (P < .001). There was evidence of publication bias for recanalization rates (P = .01), but not for clinical outcomes (P = .42).

CONCLUSIONS:

ADAPT and aspiration thrombectomy are effective approaches to thrombectomy, with high recanalization rates and excellent clinical outcomes reported in the literature. Aspiration thrombectomy is a promising neurointervention, but large prospective randomized studies are needed to validate its utility.

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Endovascular Treatment of Dural Arteriovenous Fistulas of the Transverse and Sigmoid Sinuses Using Transarterial Balloon-Assisted Embolization Combined with Transvenous Balloon Protection of the Venous Sinus [INTERVENTIONAL]  Voir?

BACKGROUND AND PURPOSE:

Combined transarterial balloon-assisted endovascular embolization with double-lumen balloon microcatheters and concomitant transvenous balloon protection was described as a promising treatment technique for dural arteriovenous fistulae of the transverse and sigmoid sinus. The purpose of this study was to evaluate the technical efficacy and safety of this combined treatment technique.

MATERIALS AND METHODS:

Nine consecutive patients presenting with dural arteriovenous fistulas of the transverse and sigmoid sinuses underwent combined transarterial and transvenous balloon-assisted endovascular embolization. Prospectively collected data were reviewed to assess the technical success rate, complication rate, and clinical outcome.

RESULTS:

Six patients presented with clinically symptomatic Borden type I, and 3 patients, with Borden type II dural arteriovenous fistulas of the transverse and sigmoid sinuses (3 men, 6 women; mean age, 50.4 years). Transarterial embolization was performed with a double-lumen balloon with Onyx and concomitant transvenous sinus protection with a dedicated venous remodeling balloon. Complete angiographic occlusion at the latest follow-up (mean, 4.8 months) was achieved in 6 patients, and near-complete occlusion, in 2 patients. Clinical cure or remission of symptoms was obtained in 6 and 2 patients, respectively. One patient with a residual fistula underwent further treatment in which the dural arteriovenous fistula was cured by sinus occlusion. Complete occlusion of the dural arteriovenous fistula was visible on the follow-up angiography after final treatment in 8 patients. One patient refused follow-up angiography but was free of symptoms. There were no immediate or delayed postinterventional complications.

CONCLUSIONS:

Transarterial balloon-assisted embolization of dural arteriovenous fistulas of the transverse and sigmoid sinuses with combined transvenous balloon protection is safe and offers a high rate of complete dural arteriovenous fistula occlusion and remission of clinical symptoms.

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Anatomic Location of Tumor Predicts the Accuracy of Motor Function Localization in Diffuse Lower-Grade Gliomas Involving the Hand Knob Area [FUNCTIONAL]  Voir?

BACKGROUND AND PURPOSE:

The accuracy of preoperative blood oxygen level–dependent fMRI remains controversial. This study assessed the association between the anatomic location of a tumor and the accuracy of fMRI-based motor function mapping in diffuse lower-grade gliomas.

MATERIALS AND METHODS:

Thirty-five patients with lower-grade gliomas involving motor areas underwent preoperative blood oxygen level–dependent fMRI scans with grasping tasks and received intraoperative direct cortical stimulation. Patients were classified into an overlapping group and a nonoverlapping group, depending on the extent to which blood oxygen level–dependent fMRI and direct cortical stimulation results concurred. Tumor location was quantitatively measured, including the shortest distance from the tumor to the hand knob and the deviation distance of the midpoint of the hand knob in the lesion hemisphere relative to the midline compared with the normal contralateral hemisphere.

RESULTS:

A 4-mm shortest distance from the tumor to the hand knob value was identified as optimal for differentiating the overlapping and nonoverlapping group with the receiver operating characteristic curve (sensitivity, 84.6%; specificity, 77.8%). The shortest distances from the tumor to the hand knob of ≤4 mm were associated with inaccurate fMRI-based localizations of the hand motor cortex. The shortest distances from the tumor to the hand knob were larger (P = .002), and the deviation distances for the midpoint of the hand knob in the lesion hemisphere were smaller (P = .003) in the overlapping group than in the nonoverlapping group.

CONCLUSIONS:

This study suggests that the shortest distance from the tumor to the hand knob and the deviation distance for the midpoint of the hand knob on the lesion hemisphere are predictive of the accuracy of blood oxygen level–dependent fMRI results. Smaller shortest distances from the tumor to the hand knob and larger deviation distances for the midpoint of hand knob on the lesion hemisphere are associated with less accuracy of motor cortex localization with blood oxygen level–dependent fMRI. Preoperative fMRI data for surgical planning should be used cautiously when the shortest distance from the tumor to the hand knob is ≤4 mm, especially for lower-grade gliomas anterior to the central sulcus.

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Flat Panel Angiography in the Cross-Sectional Imaging of the Temporal Bone: Assessment of Image Quality and Radiation Dose Compared with a 64-Section Multisection CT Scanner [HEAD & NECK]  Voir?

BACKGROUND AND PURPOSE:

Cross-sectional imaging of the temporal bone is challenging because of the complexity and small dimensions of the anatomic structures. We evaluated the role of flat panel angiography in the cross-sectional imaging of the temporal bone by comparing its image quality and radiation dose with a 64-section multisection CT scanner.

MATERIALS AND METHODS:

We retrospectively collected 29 multisection CT and 29 flat panel angiography images of normal whole-head temporal bones. Image quality was assessed by 2 neuroradiologists, who rated the visualization of 30 anatomic structures with a 3-point ordinal scale. The radiation dose was assessed with an anthropomorphic phantom.

RESULTS:

Flat panel angiography showed better image quality than multisection CT in depicting the anterior and posterior crura of the stapes, the footplate of the stapes, the stapedius muscle, and the anterior ligament of the malleus (P < .05). In contrast, multisection CT showed better image quality than flat panel angiography in assessing the tympanic membrane, the bone marrow of the malleus and incus, the tendon of the tensor tympani, the interscalar septum, and the modiolus of the cochlea (P < .05). Flat panel angiography had a significantly higher overall image quality rating than multisection CT (P = .035). A reduction of the effective dose of approximately 40% was demonstrated for flat panel angiography compared with multisection CT.

CONCLUSIONS:

Flat panel angiography shows strengths and weaknesses compared with multisection CT. It is more susceptible to artifacts, but due to the higher spatial resolution, it shows equal or higher image quality in assessing some bony structures of diagnostic interest. The lower radiation dose is an additional advantage of flat panel angiography.

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Measurement for Detection of Incomplete Partition Type II Anomalies on MR Imaging [PEDIATRICS]  Voir?

BACKGROUND AND PURPOSE:

Incomplete partition type II of the cochlea, commonly coexisting with an enlarged vestibular aqueduct, can be a challenging diagnosis on MR imaging due to the presence of a dysplastic spiral lamina–basilar membrane neural complex, which can resemble the normal interscalar septum. The purpose of this study was to determine a reproducible, quantitative cochlear measurement to assess incomplete partition type II anomalies in patients with enlarged vestibular aqueducts using normal-hearing ears as a control population.

MATERIALS AND METHODS:

Retrospective analysis of 27 patients with enlarged vestibular aqueducts (54 ears) and 28 patients (33 ears) with normal audiographic findings who underwent MR imaging was performed. Using reformatted images from a cisternographic 3D MR imaging produced in a plane parallel to the lateral semicircular canal, we measured the distance (distance X) between the osseous spiral lamina-basilar membrane complex of the upper basal turn and the first linear signal void anterior to the basilar membrane.

RESULTS:

The means of distance X in patients with normal hearing and prospectively diagnosed incomplete partition type II were, respectively, 0.93 ± 0.075 mm (range, 0.8–1.1 mm) and 1.55 ± 0.25 mm (range, 1–2.1 mm; P < .001). Using 3 SDs above the mean of patients with normal hearing (1.2 mm) as a cutoff for normal, we diagnosed 21/27 patients as having abnormal cochleas; 4/21 were diagnosed retrospectively. This finding indicated that almost 20% of patients were underdiagnosed. Interobserver agreement with 1.2 mm as a cutoff between normal and abnormal produced a score of 0.715 (good).

CONCLUSIONS:

Incomplete partition type II anomalies on MR imaging can be subtle. A reproducible distance X of ≥1.2 mm is considered abnormal and may help to prospectively diagnose incomplete partition type II anomalies.

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Localizing the L5 Vertebra Using Nerve Morphology on MRI: An Accurate and Reliable Technique [SPINE]  Voir?

BACKGROUND AND PURPOSE:

Multiple methods have been used to determine the lumbar vertebral level on MR imaging, particularly when full spine imaging is unavailable. Because postmortem studies show 95% accuracy of numbering the lumbar vertebral bodies by counting the lumbar nerve roots, attention to lumbar nerve morphology on axial MR imaging can provide numbering clues. We sought to determine whether the L5 vertebra could be accurately localized by using nerve morphology on MR imaging.

MATERIALS AND METHODS:

One hundred eight cases with full spine MR imaging were numbered from the C2 vertebral body to the sacrum with note of thoracolumbar and lumbosacral transitional states. The origin level of the L5 nerve and iliolumbar ligament were documented in all cases. The reference standard of numbering by full spine imaging was compared with the nerve morphology numbering method. Five blinded raters evaluated all lumbar MRIs with nerve morphology technique twice. Prevalence and bias-adjusted were used to measure interrater and intrarater reliability.

RESULTS:

The L5 nerve arose from the 24th presacral vertebra (L5) in 106/108 cases. The percentage of perfect agreement with the reference standard was 98.1% (95% CI, 93.5%–99.8%), which was preserved in transitional and numeric variation states. The iliolumbar ligament localization method showed 83.3% (95% CI, 74.9%–89.8%) perfect agreement with the reference standard. Inter- and intrarater reliability when using the nerve morphology method was strong.

CONCLUSIONS:

The exiting L5 nerve can allow accurate localization of the corresponding vertebrae, which is essential for preprocedure planning in cases where full spine imaging is not available. This neuroanatomic method displays higher agreement with the reference standard compared with previously described methods, with strong inter- and intrarater reliability.

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Test-Retest and Interreader Reproducibility of Semiautomated Atlas-Based Analysis of Diffusion Tensor Imaging Data in Acute Cervical Spine Trauma in Adult Patients [SPINE]  Voir?

BACKGROUND AND PURPOSE:

DTI is a tool for microstructural spinal cord injury evaluation. This study evaluated the reproducibility of a semiautomated segmentation algorithm of spinal cord DTI.

MATERIALS AND METHODS:

Forty-two consecutive patients undergoing acute trauma cervical spine MR imaging underwent 2 axial DTI scans in addition to their clinical scan. The datasets were put through a semiautomated probabilistic segmentation algorithm that selected white matter, gray matter, and 24 individual white matter tracts. Regional and white matter tract volume, fractional anisotropy, and mean diffusivity values were calculated. Two readers performed the nonautomated steps to evaluate interreader reproducibility. The coefficient of variation and intraclass correlation coefficient were used to assess test-retest and interreader reproducibility.

RESULTS:

Of 42 patients, 30 had useable data. Test-retest reproducibility of fractional anisotropy was high for white matter as a whole (coefficient of variation, 3.8%; intraclass correlation coefficient, 0.93). Test-retest coefficient-of-variation ranged from 8.0%–18.2% and intraclass correlation coefficients from 0.47–0.80 across individual white matter tracts. Mean diffusivity metrics also had high test-retest reproducibility (white matter: coefficient-of-variation, 5.6%; intraclass correlation coefficient, 0.86) with coefficients of variation from 11.6%–18.3% and intraclass correlation coefficients from 0.57–0.74 across individual tracts, with better agreement for larger tracts. The coefficients of variation of fractional anisotropy and mean diffusivity both had significant negative relationships with white matter volume (26%–27% decrease for each doubling of white matter volume, P < .01).

CONCLUSIONS:

DTI spinal cord segmentation is reproducible in the setting of acute spine trauma, specifically for larger white matter tracts and total white or gray matter.

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Yield of Image-Guided Needle Biopsy for Infectious Discitis: A Systematic Review and Meta-Analysis [SPINE]  Voir?

BACKGROUND:

Image-guided biopsy is routinely conducted in patients with suspected discitis, though the sensitivity reported in the literature ranges widely.

PURPOSE:

We applied a systematic review and meta-analysis to estimate the yield of image-guided biopsy for infectious discitis.

DATA SOURCES:

We performed a literature search of 4 data bases: PubMed, Cochrane CENTRAL Register of Controlled Trials, Embase.com, and Scopus from data base inception to March 2016.

STUDY SELECTION:

A screen of 1814 articles identified 88 potentially relevant articles. Data were extracted for 33 articles, which were eligible if they were peer-reviewed publications of patients with clinical suspicion of discitis who underwent image-guided biopsy.

DATA ANALYSIS:

Patients with positive cultures out of total image-guided biopsy procedures were pooled to estimate yield with 95% confidence intervals. Hypothesis testing was performed with an inverse variance method after logit transformation.

DATA SYNTHESIS:

Image-guided biopsy has a yield of approximately 48% (793/1763), which is significantly lower than the open surgical biopsy yield of 76% (152/201; P < .01). Biopsy in patients with prior antibiotic exposure had a yield of 32% (106/346), which was not significantly different from the yield of 43% (336/813; P = .08) in patients without prior antibiotic exposure.

LIMITATIONS:

The conclusions of this meta-analysis are primarily limited by the heterogeneity of the included studies.

CONCLUSIONS:

Image-guided biopsy has a moderate yield for the diagnosis of infectious discitis, which is significantly lower than the yield of open surgical biopsy. This yield is not significantly affected by prior antibiotic use.

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[18F]-Sodium Fluoride PET MR-Based Localization and Quantification of Bone Turnover as a Biomarker for Facet Joint-Induced Disability [SPINE]  Voir?

SUMMARY:

Our aim was to prospectively evaluate the relationship between low back pain–related disability and quantitative measures from [18F]-sodium fluoride ([18F]-NaF) MR imaging. Six patients with facetogenic low back pain underwent dynamic [18F]-NaF PET/MR imaging. PET metrics were correlated with clinical measures and MR imaging grading of lumbar facet arthropathy. A significant positive correlation was observed between maximum facet joint uptake rate and clinical disability (P < .05). These data suggest that dynamic [18F]-NaF PET may serve as a useful biomarker for facetogenic disability.

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Dernière mise à jour : 16/10/2017 : 07:13


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