Prognostic Value of Apparent Diffusion Coefficient (ADC) in Patients with Diffuse Gliomas.

This study aimed to evaluate potential posttreatment changes in ADC values within the tissue surrounding the enhancing lesion, particularly in areas not exhibiting MRI characteristics of involvement. Additionally, the objective was to investigate the correlations among ADC values, treatment response, and survival outcomes in individuals diagnosed with gliomas. This retrospective study included a total of 49 patients that underwent either stereotactic biopsy or maximal surgical resection. Histologically confirmed as Grade III or IV gliomas, all cases adhered to the 2016 and 2021 WHO classifications, with subsequent radio-chemotherapy administered post-surgery. Patients were divided into two groups: short and long survival groups. Baseline and follow-up MRI scans were obtained on a 1.5 T MRI scanner. Two ROI circles were positioned near the enhancing area, one ROI in the NAWM ipsilateral to the neoplasm and another symmetrically in the contralateral hemisphere on ADC maps. At follow-up there was a significant difference in both ipsilateral and contralateral NAWM between the two groups, -0.0857 (p = 0.004) and -0.0607 (p = 0.037), respectively. There was a weak negative correlation between survival and ADC values in ipsilateral and contralateral NAWM at the baseline with the correlation coefficient -0.328 (p = 0.02) and -0.302 (p = 0.04), respectively. The correlation was stronger at the follow-up. The findings indicate that ADC values in normal-appearing white matter (NAWM) may function as a prognostic biomarker in patients with diffuse gliomas.

Virtual monoenergetic dual-energy CT reconstructions at 80 keV are optimal non-contrast CT technique for early stroke detection.

BACKGROUND: Virtual monoenergetic (VM) dual-energy computed tomography (DE-CT) enables grey-to-white matter contrast-to-noise ratio optimization, potentially increasing ischaemic brain oedema visibility. The aim of this study was to compare the diagnostic accuracy of VM and standard DE-CT reconstructions for early stroke detection. METHODS: Consecutive patients with non-contrast DE-CT of the brain scanned within 12 h of stroke symptom onset were prospectively included in the study. Patients with other significant brain pathology were excluded. Two radiologists jointly evaluated standard and VM reconstructions (from 40 to 190 keV at increments of 10 keV) for early stroke signs on a four-point Likert scale: (a) stroke definitely present, (b) stroke probably present, (c) probably no stroke, and (d) definitely no stroke. Follow-up imaging and clinical data served as the standard of reference. Diagnostic accuracy was evaluated by receiver operating characteristic analysis. RESULTS: Stroke incidence among 184 patients was 76%. In 64 patients follow-up imaging served as the standard of reference: ischemic brain oedema detection was significantly more accurate on VM reconstructions at 80 keV compared with standard DE-CT reconstructions (area under the curve (AUC) = 0.821 vs. AUC = 0.672, p = 0.002). The difference was most prominent within the first 3 h after symptom onset (at 11%, AUC = 0.819 vs. AUC = 0.709, p = 0.17) and in patients with National Institutes of Health Stroke Scale above 16 (at 37.5%, AUC = 1 vs. AUC = 0.625, p = 0.14). CONCLUSION: VM DE-CT reconstructions at 80 keV appear to be the optimal non-contrast CT technique for diagnosing early ischaemic stroke, particularly within the first 3 h after symptom onset and in severely ill patients.

Bilateral lesions of the basal ganglia and thalami (central grey matter)-pictorial review.

The basal ganglia and thalami are paired deep grey matter structures with extensive metabolic activity that renders them susceptible to injury by various diseases. Most pathological processes lead to bilateral lesions, which may be symmetric or asymmetric, frequently showing characteristic patterns on imaging studies. In this comprehensive pictorial review, the most common and/or typical genetic, acquired metabolic/toxic, infectious, inflammatory, vascular and neoplastic pathologies affecting the central grey matter are subdivided according to the preferential location of the lesions: in the basal ganglia, in the thalami or both. The characteristic imaging findings are described with emphasis on the differential diagnosis and clinical context.

Comparing image quality of single- and dual-energy computed tomography of the brain.

PURPOSE: Weighted average dual-energy computed tomography (DE-CT) reconstructions are considered a proxy of standard CT images of the brain, recommended for routine clinical use and used as a reference standard in DE-CT research. However, their image quality has not been assessed, which was the aim of our study. METHODS: Images from 81 consecutive patients who underwent both non-contrast single-energy (SE)-CT and DE-CT of the brain on the same scanner were retrospectively evaluated. Attenuation values (HU) and SD of grey matter/white matter (GM/WM) pairs, along with SD in the posterior fossa and subcalvarial region were measured. Four readers evaluated image noise, GM/WM contrast, posterior fossa and subcalvarial artefacts, as well as overall image quality. RESULTS: Weighted average DE-CT GM and WM HU were significantly lower and noise higher compared to SE-CT (GM HU 36.46 v. 41.82; WM HU 28.18 v. 29.94; GM SD 2.93 v. 2.49; and WM SD 3.16 v. 2.44, all p < 0.0001). After correcting the measured SE-CT noise for 37% higher acquisition dose, DE-CT GM noise became significantly lower (2.93 v. 3.11, p = 0.0121). Measured and dose corrected SE-CT GM/WM contrast-to-noise ratio was superior to weighted average DE-CT (3.42 and 2.74 v. 1.95, both p < 0.0001). Weighted average DE-CT had significantly less artifacts on qualitative analysis. CONCLUSION: Weighted average DE-CT images of the brain yield less artefacts at 37% dose reduction and lower noise at SE-CT equivalent dose. Dose-adjusted GM/WM contrast-to-noise ratio of weighted average DE-CT with 0.4 weighting factor remains inferior to SE-CT images.

Perilesional apparent diffusion coefficient in the preoperative evaluation of glioma grade.

Preoperative identification of high-grade gliomas is critical to optimize treatment strategy and to predict prognosis. To determine whether perilesional apparent diffusion coefficient (ADC) values differ between high- and low-grade tumors, we assessed water diffusivity within normal-appearing brain parenchyma (NABP) surrounding gliomas in twenty-one treatment-naïve patients. This showed significantly lower mean and 25th percentile (Q1) ADC values in high- grade compared to low-grade gliomas respectively in the range of 10-25 and 10-30 mm away from combined tumor and surrounding T2 signal. Thus, perilesional ADC measurement may reflect the extent of tumor infiltration beyond the abnormality seen on conventional MRI.

The Role of Limited Head Computed Tomography in the Evaluation of Pediatric Ventriculoperitoneal Shunt Malfunction.

BACKGROUND: The evaluation of children with suspected ventriculoperitoneal shunt (VPS) malfunction has evolved into a diagnostic dilemma. This patient population is vulnerable not only to the medical risks of hydrocephalus and surgical complications but also to silent but harmful effects of ionizing radiation secondary to imaging used to evaluate shunt efficacy and patency. The combination of increased medical awareness regarding ionizing radiation and public concern has generated desire to reduce the reliance on head computed tomography (CT) for the evaluation of VPS malfunction. Many centers have started to investigate the utility of low-dose CT scans and alternatives, such as fast magnetic resonance imaging for the investigation of VP shunt malfunction in order to keep radiation exposure as low as reasonably achievable. This pilot study hopes to add to the armamentarium available to the clinician charged with evaluating this challenging patient population by testing the feasibility of a limited CT protocol as an alternative to a full head CT examination. OBJECTIVE: To evaluate the efficacy of a limited head CT protocol compared with a complete head CT for the evaluation of children presenting to the pediatric emergency department with suspected shunt malfunction. METHODS: We retrospectively reviewed all pediatric patients who received a head CT for suspected VPS malfunction evaluation at a tertiary care children's hospital from January 2001 through January 2013. Children were included in the pilot study if they had at least 2 CT scans in this study period interpreted by a specific senior attending neuroradiologist. For each patient enrolled, a limited series was generated from the most recent CT scan by selecting four representative axial slices based on the sagittal scout image. These 4 slices where selected at the level of the fourth ventricle, third ventricle, basal ganglia level, and lateral ventricles, respectively. A blinded, senior attending neuroradiologist first reviewed the limited 4-slice CT data set and was asked to determine if the ventricular system had increased, decreased, or remained stable. Subsequently, the neuroradiologist compared their interpretation of the limited examination with the official report from the full CT data set as the standard of reference as well as the interpretation of the most recent prior scan. RESULTS: Forty-six patients (age range, 2 months to 18 years; average age, 6.4 years (SD, 4.2), 54% male) were included in the study. Forty-four of 46 (95.7%) limited CT scans matched the official report of the full CT scan. No cases of increased ventricular size were missed (100% positive predictive value for increased ventricular size). The use of a limited head CT (4 axial images) instead of a complete head CT (average of 31 axial images in our studied patients) confers a radiation dose reduction of approximately 87%. CONCLUSIONS: Our pilot study demonstrates that utilization of limited head CT scan in the evaluation of children with suspected VP shunt malfunction is a feasible strategy for the evaluation of the ventricular size. Further prospective and multidisciplinary studies are needed to evaluate the reliability of limited head CT for the clinical evaluation of VP shunt malfunction.

Radiation intensity (CTDIvol) and visibility of anatomical structures in head CT examinations.

The purpose of this study was to quantify how changing the amount of radiation used to perform routine head CT examinations (CTDIvol) affects visibility of key anatomical structures. Eight routine noncontrast head CT exams were selected from six CT scanners, each of which had a different CTDIvol setting (60 to 75 mGy). All exams were normal and two slices were selected for evaluation, one at the level of basal ganglia and the other at the fourth ventricle. Three experienced neuroradiologists evaluated the visibility of selected structures, including the putamen, caudate nucleus, thalamus, internal capsule, grey/white differentiation, and brainstem. Images were scored on a five-point scoring scheme (1, unacceptable, 3, satisfactory, and 5, excellent). Reader scores, averaged over the cases obtained from each scanner, were plotted as a function of the corresponding CTDIvol. Average scores for the fourth ventricle were 3.06 ± 0.83 and for the basal ganglia were 3.20 ± 0.86. No image received a score of 1. Two readers showed no clear trend of an increasing score with increasing CTDIvol. One reader showed a slight trend of increasing score with increasing CTDIvol, but the increase in score from a 25% increase in CTDIvol was a fraction of the standard deviation associated average scores. Collectively, results indicated that there were no clear improvements in visualizing neuroanatomy when CTDIvol increased from 60 to 75 mGy in routine head CT examinations. Our study showed no apparent benefit of using more than 60 mGy when performing routine noncontrast head CT examinations.

Frequency, Risk Factors, and Outcome of Coexistent Small Vessel Disease and Intracranial Arterial Stenosis: Results From the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) Trial.

IMPORTANCE: Intracranial arterial stenosis (ICAS) and small vessel disease (SVD) may coexist. There are limited data on the frequency and risk factors for coexistent SVD and the effect of SVD on stroke recurrence in patients receiving medical treatment for ICAS. OBJECTIVE: To investigate the frequency and risk factors for SVD and the effect of SVD on stroke recurrence in patients with ICAS. DESIGN, SETTING, AND PARTICIPANTS: A post hoc analysis of the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) study, a prospective, multicenter clinical trial. Among 451 participants, 313 (69.4%) had baseline brain magnetic resonance imaging scans read centrally for SVD that was defined by any of the following: old lacunar infarction, grade 2 to 3 on the Fazekas scale (for high-grade white matter hyperintensities), or microbleeds. Patient enrollment in SAMMPRIS began November 25, 2008, and follow-up ended on April 30, 2013. Data analysis for the present study was performed from May 13, 2014, to July 29, 2015. MAIN OUTCOMES AND MEASURES: Risk factors in patients with vs without SVD and the association between SVD and other baseline risk factors with any ischemic stroke and ischemic stroke in the territory of the stenotic artery determined using proportional hazards regression. RESULTS: Of 313 patients, 155 individuals (49.5%) had SVD noted on baseline magnetic resonance imaging. Variables that were significantly higher in patients with SVD, reported as mean (SD), included age, 63.5 (10.5) years (P < .001), systolic blood pressure, 149 (22) mm Hg (P < .001), glucose level, 130 (50) mg/dL (P = .03), and lower Montreal Cognitive Assessment scores (median, ≥24 [interquartile range, 20-26]; P = .02).Other significant variables were the number of patients with diabetes mellitus (88 of 155 [56.8%]; P = .003), coronary artery disease (46 [29.7%]; P = .004), stroke before the qualifying event (59 [38.1%]; P < .001), old infarct in the territory of the stenotic intracranial artery (88 [56.8%]; P < .001), and receiving antithrombotic therapy at the time of the qualifying event (109 [70.3%]; P = .005). The association between SVD and any ischemic stroke was nearly significant in the direction of a higher risk (18 [23.7%]); P = .07) for patients with SVD. On bivariate analysis, SVD was not associated with an increased risk on multivariable analyses (hazard ratio, 1.7 [95% CI, 0.8-3.8]; P = .20). In addition, SVD was not associated with an increased risk of stroke in the territory on either bivariate or multivariable analyses. CONCLUSIONS AND RELEVANCE: Although SVD is common in patients with ICAS, the presence of SVD on baseline magnetic resonance imaging is not independently associated with an increased risk of stroke in patients with ICAS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00576693.

CT features and pathologic characteristics of IgG4-related systemic disease of submandibular gland.

The submandibular gland is one of the most frequently affected salivary gland in IgG4-related systemic disease, usually demonstrate homogeneous attenuation on CT imaging as reported, but without much pathological comparison of many cases. This article is to investigate and analyze the typical CT findings and pathologic characteristics of IgG4-related systemic disease (IgG4-RSD) of submandibular gland. A retrospective analysis of the preoperative CT findings in patients with IgG4-RSD of submandibular glands who underwent surgical resection between January 2010 and February 2014 was performed. Twenty patients (16 women) were identified, with a mean age of 58.1±10.2 years. All patients presented with painless submandibular gland swelling. Diffuse gland enlargement, with clear margins and homogeneous density, was found on non-enhanced CT scans in all cases. There were no calcifications or stones within the involved glands. Based on contrast-enhanced CT appearance the patients could be divided into two groups: 11 cases showed homogeneous gland enhancement; and multiple hyperenhancing foci, with a crazy-paving pattern, were detected in 9 cases, which were in consistent with the pathologic findings. The maximum submandibular gland diameter on transverse images was significantly larger (P=0.008) in patients with crazy-paving appearance (32±4 mm) compared to patients with homogeneous enhancement (28±3 mm). It is concluded that the submandibular glands with IgG4-RSD can be characterized by either homogenous appearance or crazy-paving pattern on contrast-enhanced CT imaging.

Characterization of intracranial atherosclerotic stenosis using high-resolution MRI study--rationale and design.

BACKGROUND: Intracranial atherosclerosis is a leading cause of stroke, but little is known about the composition of the intracranial atherosclerotic lesion and how intracranial plaque morphology is related to the risk of stroke. High-resolution magnetic resonance imaging (HR MRI) has been used in patients with extracranial carotid atherosclerosis as an in vivo tool to identify, with high-interrater agreement, histologically defined plaque components (i.e., intraplaque hemorrhage, fibrous cap, and lipid core), which have been shown to be predictors of recurrent stroke. With careful imaging the components of atherosclerotic plaque can be visualized in the intracranial arteries using HR MRI, but there are no reports of reproducibility or interrater reliability. METHODS/STUDY DESIGN: The Characterization of intracranial atherosclerotic stenosis using high-resolution MRI (CHIASM) study is a single-center NIH-funded prospective observational study, to (1) demonstrate high -interrater agreement for identifying intracranial plaque components on HR MRI, (2) determine the frequency of these components in symptomatic versus asymptomatic plaques, and (3) estimate the 1-year rate of stroke in the territory of high-risk plaque components. CHIASM will recruit 90 patients with 50-99% intracranial atherosclerosis to undergo HRMRI of the intracranial artery plaque at enrollment and 1-year follow-up. Both symptomatic and asymptomatic subjects will be recruited. CONCLUSION: Determination of good interrater reliability is an important first step in the development of HR MRI as a tool to predict risk in patients with intracranial atherosclerosis. This study will inform the design of future multicenter studies to determine the prevalence and prognosis of intracranial atherosclerotic plaque components. Such studies could lead to new understanding of the pathophysiological mechanisms of cerebral ischemia in patients with atherosclerotic intracranial stenosis, improvements in risk stratification, and potentially to new treatments of this common and serious disease.

Intracranial atherosclerosis: correlation between in-vivo 3T high resolution MRI and pathology.

BACKGROUND: High-resolution MRI (HRMRI) is a promising tool for studying intracranial atherosclerotic disease (ICAD) in-vivo, but its use to understand the pathophysiology of ICAD has been limited by a lack of correlation between MRI signal characteristics and pathology in intracranial arteries. DESCRIPTION OF CASE: A patient with symptomatic left cavernous carotid stenosis underwent 3T HRMRI and died 4 days later. In-vivo HRMRI and postmortem histopathology images were compared. MRI signal characteristics consistent with atherosclerotic plaque composed of lipid and loose matrix, fibrous tissue, and calcium were correlated with pathology findings. Intraplaque hemorrhage was not present on HRMRI or pathology. CONCLUSIONS: This report demonstrates correlation between atherosclerotic plaque components visualized on 3T HRMRI images obtained in-vivo and pathological specimens of a symptomatic ICAD plaque, providing an important step in developing HRMRI as an in-vivo research tool to understand ICAD pathology.

Combining percutaneous pedicular and extrapedicular access for tumor ablation in a thoracic vertebral body.

We present a percutaneous modified technique to access large thoracic vertebral body lytic lesions, to increase the volume of tumor accessible to ablation, prior to cement augmentation. Tumor ablation and cavity creation-assisted percutaneous vertebroplasty was considered a palliative measure for structural stabilization in plasmocytoma involvement of the entire T8 vertebral body. Given the extent of osteolysis bilateral combined transpedicular and extrapedicular access to the vertebral body was undertaken to maximize the volume of cavity creation within the tumor. The combined transpedicular and extrapedicular access was feasible, uncomplicated, and successful in reaching all the quadrants of the anterior two thirds of the vertebral body. Slow, fluoroscopically monitored injection of high-viscosity cement resulted in a successful, desired cement distribution into the anterior two thirds of the vertebral body, spanning superior to inferior endplates, providing structural stability, in the absence of venous or epidural leakage. The technical modification described in this case yielded positive results while overcoming some of the limitations of the existing coblation device. This approach may offer an option for cement augmentation of extensive vertebral body lytic lesions, at increased risk for tumor displacement and extra-vertebral cement leakage.

Infarct patterns, collaterals and likely causative mechanisms of stroke in symptomatic intracranial atherosclerosis.

BACKGROUND: There are limited data on the specific mechanisms of stroke in patients with intracranial atherosclerotic stenosis (ICAS). We undertook this study to describe infarct patterns and likely mechanisms of stroke in a large cohort of patients with ICAS, and to evaluate the relationship of these infarct patterns to angiographic features (collaterals, stenosis location and stenosis severity). METHODS: We evaluated infarct patterns in the territory of a stenotic intracranial artery on neuroimaging performed at baseline and during follow-up if a recurrent stroke occurred in patients enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial. We defined the likely mechanism of stroke (artery-to-artery embolism, perforator occlusion, hypoperfusion or mixed) according to the site of ICAS and based on the infarct patterns on neuroimaging. Collaterals were assessed using American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grades, and stenosis severity using the WASID trial's measurement technique. We evaluated the association of infarct patterns with angiographic features using χ(2) tests. RESULTS: The likely mechanisms of stroke based on the infarct patterns at baseline in the 136 patients included in the study were artery-to-artery embolism (n = 69; 50.7%), perforator occlusion (n = 34; 25%), hypoperfusion (n = 12; 8.8%) and mixed (n = 21; 15.5%). Perforator-occlusive infarcts were more frequent in the posterior circulation, and mixed patterns were more prevalent in the anterior circulation (both p < 0.01). Most of the mixed patterns in the anterior circulation combined small pial or scattered multiple cortical infarcts with infarcts in border-zone regions, especially the cortical ones. Isolated border-zone infarcts were not significantly associated with a poor grading for collaterals or the severity of stenosis. Among 47 patients with a recurrent infarct during follow-up, the infarct patterns suggested an artery-to-artery embolic mechanism in 29 (61.7%). CONCLUSIONS: Artery-to-artery embolism is probably the most common mechanism of stroke in both the anterior and the posterior circulations in patients with ICAS. An extension of intracranial atherosclerosis at the site of stenosis into adjacent perforators also appears to be a common mechanism of stroke, particularly in the posterior circulation, whereas hypoperfusion as the sole mechanism is relatively uncommon. Further research is important to accurately establish the specific mechanisms of stroke in patients with ICAS, since preliminary data suggest that the underlying mechanism of stroke is an important determinant of prognosis.

Tilting the gantry for CT-guided spine procedures.

Percutaneous spine procedures can be performed with computed tomography (CT) guidance. The use of CT guidance is cumbersome for procedures where an oblique needle trajectory is imposed by the spatial orientation of the spine, often requiring complex needle triangulation relative to the true axial scan plane. We describe a procedural modification to overcome this limitation. A combination of variable CT gantry tilt, and strategic bolster placement under the patient can be used to obtain optimal imaging planes for guidance along the desired needle trajectory. The needle is aligned with the CT gantry laser beam to guide the needle access to the target, maintained within a single CT slice. We describe our clinical experience using the modified procedure relative to the conventional technique, and provide representative examples.

Aggressive medical treatment with or without stenting in high-risk patients with intracranial artery stenosis (SAMMPRIS): the final results of a randomised trial.

BACKGROUND: Early results of the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis trial showed that, by 30 days, 33 (14·7%) of 224 patients in the stenting group and 13 (5·8%) of 227 patients in the medical group had died or had a stroke (percentages are product limit estimates), but provided insufficient data to establish whether stenting offered any longer-term benefit. Here we report the long-term outcome of patients in this trial. METHODS: We randomly assigned (1:1, stratified by centre with randomly permuted block sizes) 451 patients with recent transient ischaemic attack or stroke related to 70-99% stenosis of a major intracranial artery to aggressive medical management (antiplatelet therapy, intensive management of vascular risk factors, and a lifestyle-modification programme) or aggressive medical management plus stenting with the Wingspan stent. The primary endpoint was any of the following: stroke or death within 30 days after enrolment, ischaemic stroke in the territory of the qualifying artery beyond 30 days of enrolment, or stroke or death within 30 days after a revascularisation procedure of the qualifying lesion during follow-up. Primary endpoint analysis of between-group differences with log-rank test was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT 00576693. FINDINGS: During a median follow-up of 32·4 months, 34 (15%) of 227 patients in the medical group and 52 (23%) of 224 patients in the stenting group had a primary endpoint event. The cumulative probability of the primary endpoints was smaller in the medical group versus the percutaneous transluminal angioplasty and stenting (PTAS) group (p=0·0252). Beyond 30 days, 21 (10%) of 210 patients in the medical group and 19 (10%) of 191 patients in the stenting group had a primary endpoint. The absolute differences in the primary endpoint rates between the two groups were 7·1% at year 1 (95% CI 0·2 to 13·8%; p=0·0428), 6·5% at year 2 (-0·5 to 13·5%; p=0·07) and 9·0% at year 3 (1·5 to 16·5%; p=0·0193). The occurrence of the following adverse events was higher in the PTAS group than in the medical group: any stroke (59 [26%] of 224 patients vs 42 [19%] of 227 patients; p=0·0468) and major haemorrhage (29 [13%]of 224 patients vs 10 [4%] of 227 patients; p=0·0009). INTERPRETATION: The early benefit of aggressive medical management over stenting with the Wingspan stent for high-risk patients with intracranial stenosis persists over extended follow-up. Our findings lend support to the use of aggressive medical management rather than PTAS with the Wingspan system in high-risk patients with atherosclerotic intracranial arterial stenosis. FUNDING: National Institute of Neurological Disorders and Stroke (NINDS) and others.

Percutaneous ethanol embolization and cement augmentation of aggressive vertebral hemangiomas at two adjacent vertebral levels.

This report describes a case of successful percutaneous direct-puncture ethanol embolization, followed by vertebroplasty, of an aggressive vertebral hemangioma (VH) involving two adjacent thoracic vertebral levels. In this case, the 78-year-old male patient presented with a 6-month history of progressive paraparesis due to spinal cord compression by a T8-T9 VH with an extensive epidural component. Follow-up demonstrated epidural component shrinkage with complete regression of symptoms at 3 months. This case suggests that exclusive percutaneous treatment may be considered for symptomatic VH even when two adjacent vertebral levels are affected.

Accuracy of CT guidance of lumbar facet joint block.

OBJECTIVE: Lumbar facet joint block is generally performed under fluoroscopic guidance. The purpose of this study was to assess the technical success rate of facet joint block under CT guidance. The CT scanner was operated tableside with a step-and-shoot mode for intermittent needle visualization, and the amount of radiation used to perform the procedures was estimated. CONCLUSION: CT-guided facet joint block is safe and rapid. Use of CT ensures reliable needle guidance with extremely high procedural accuracy at an effective radiation dose comparable to that of a procedure performed with 1 minute of fluoroscopic guidance.

High-resolution MRI of basilar atherosclerosis: three-dimensional acquisition and FLAIR sequences.

This case report describes the use of high-resolution magnetic resonance imaging (HRMRI) to visualize basilar artery atherosclerotic plaque in a patient with a pontine stroke. HRMRI with three-dimensional image acquisition was used to visualize plaque in several planes to localize arterial wall pathology. Fluid attenuated inversion recovery (FLAIR) sequences of the basilar artery showed wall thickening throughout the basilar artery wall and good contrast between the artery wall and cerebrospinal fluid.

Mechanisms of stroke after intracranial angioplasty and stenting in the SAMMPRIS trial.

BACKGROUND: Enrollment in the stenting and aggressive medical management for the prevention of stroke in intracranial stenosis (SAMMPRIS) trial was halted owing to higher-than-expected 30-day stroke rates in the stenting arm. Improvement in periprocedural stroke rates from angioplasty and stenting for intracranial atherosclerotic disease (ICAD) requires an understanding of the mechanisms of these events. OBJECTIVE: To identify the types and mechanisms of periprocedural stroke after angioplasty and stenting for ICAD. METHODS: Patients who experienced a hemorrhagic or ischemic stroke or a cerebral infarct with temporary signs within 30 days of attempted angioplasty and stenting in SAMMPRIS were identified. Study records, including case report forms, procedure notes, and imaging were reviewed. Strokes were categorized as ischemic or hemorrhagic. Ischemic strokes were categorized as perforator territory, distal embolic, or delayed stent thrombosis. Hemorrhagic strokes were categorized as subarachnoid or intraparenchymal. Causes of hemorrhage (wire perforation, vessel rupture) were recorded. RESULTS: Three patients had an ischemic stroke after diagnostic angiography. Two of these strokes were unrelated to the procedure. Twenty-one patients had an ischemic stroke (n = 19) or cerebral infarct with temporary signs (n = 2) within 30 days of angioplasty and stenting. Most (n = 15) were perforator territory and many of these occurred after angiographically successful angioplasty and stenting of the basilar artery (n = 8). Six patients experienced a subarachnoid hemorrhage (3 from wire perforation) and 7 had a delayed intraparenchymal hemorrhage. CONCLUSION: Efforts at reducing complications from angioplasty and stenting for ICAD must focus on reducing the risks of regional perforator infarction, delayed intraparenchymal hemorrhage, and wire perforation.

Cochlear nerve deficiency in children with CHARGE syndrome.

OBJECTIVES/HYPOTHESIS: To describe cochlear nerve deficiency and abnormalities of the internal auditory canal (IAC) associated with CHARGE (coloboma, heart defects, atresia choanae, retardation of growth and/or development, genital hypoplasia, and ear anomalies and/or deafness) syndrome. STUDY DESIGN: Case series. METHODS: In a tertiary children's hospital, children with CHARGE syndrome were evaluated between 2006 and 2009. Morphology of the inner ear, IAC, and cochlear nerves was evaluated along with auditory-evoked brainstem response results. RESULTS: Of the 17 patients with CHARGE diagnosis, 14 ears demonstrated profound sensorineural hearing loss (SNHL). The remaining ears had conductive hearing loss, mixed hearing loss, or mild to moderate SNHL. Computed tomography (CT) evaluation was refused in one case and delayed in one case due to parental decision. Of 30 ears evaluated with CT, 28 (93%) had substantial abnormalities of the inner ear including hypoplasia or aplasia of the semicircular canals and abnormalities of the cochlea and vestibule. CT evaluation revealed cochlear aperture narrowing or occlusion in 16 ears, one of which had normal hearing. The eight most recent patients with profound SNHL (six bilateral SNHL, two unilateral) underwent magnetic resonance imaging (MRI) of the IAC, and 13 of 14 ears with SNHL were noted to have absent or deficient cochlear nerves. CT scans in two ears with profound SNHL revealed normal cochlear apertures. CONCLUSIONS: The dysmorphic inner ear is well described in CHARGE patients; however, cochlear nerve deficiency has not been considered a common etiology for SNHL in these patients. Because of the implications of cochlear nerve deficiency in therapeutic decision making (i.e., cochlear implantation), MRI evaluation of the eighth nerve should be considered in CHARGE patients with profound SNHL.