Background and Aims: Statin therapy is an essential component of cardiovascular preventive care. In recent years, various vessel wall MRI (VW-MRI) techniques have been used to monitor atherosclerosis progression or regression in patients... more
Background and Aims: Statin therapy is an essential component of cardiovascular preventive care. In recent years, various vessel wall MRI (VW-MRI) techniques have been used to monitor atherosclerosis progression or regression in patients with extracranial or intracranial large-artery atherosclerosis. We aimed to perform a systematic review and meta-analysis on the effects of statin therapy on plaque evolution as assessed by VW-MRI.Materials and Methods: Prospective studies investigating carotid and intracranial atherosclerotic plaques in patients on statin therapy monitored by serial VW-MRI were systematically identified in the literature. The plaque burden and lipid-rich necrotic core (LRNC) volume of carotid plaque and the imaging features of intracranial plaques were extracted and summarized. For studies investigating carotid artery wall volume and LRNC volume, combined estimates were derived by meta-analysis.Results: The study identified 21 studies of carotid plaque and two stud...
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Background and Purpose: 3D pointwise encoding time reduction magnetic resonance angiography (PETRA-MRA) is a promising non-contrast magnetic resonance angiography (MRA) technique for intracranial stenosis assessment but it has not been... more
Background and Purpose: 3D pointwise encoding time reduction magnetic resonance angiography (PETRA-MRA) is a promising non-contrast magnetic resonance angiography (MRA) technique for intracranial stenosis assessment but it has not been adequately validated against digital subtraction angiography (DSA) relative to 3D-time-of-flight (3D-TOF) MRA. The aim of this study was to compare PETRA-MRA and 3D-TOF-MRA using DSA as the reference standard for intracranial stenosis assessment before and after angioplasty and stenting in patients with middle cerebral artery (MCA) stenosis.Materials and Methods: Sixty-two patients with MCA stenosis (age 53 ± 12 years, 43 males) underwent MRA and DSA within a week for pre-intervention evaluation and 32 of them had intracranial angioplasty and stenting performed. The MRAs' image quality, flow visualization within the stents, and susceptibility artifact were graded on a 1–4 scale (1 = poor, 4 = excellent) independently by three radiologists. The deg...
Objective: To assess whether intracranial vessel wall (IVW) MRI luminal measurements are more accurate than non-contrast 3D-TOF-MRA measurements for intracranial atherosclerotic stenosis, relative to CTA. Methods: Consecutive patients... more
Objective: To assess whether intracranial vessel wall (IVW) MRI luminal measurements are more accurate than non-contrast 3D-TOF-MRA measurements for intracranial atherosclerotic stenosis, relative to CTA. Methods: Consecutive patients with non-calcified intracranial atherosclerotic stenosis seen on CTA, who had non-contrast 3D-TOF-MRA and IVW performed between 1 January 2013 and 20 April 2014 were selected, and images with stenosis were pre-selected by a single independent rater. The pre-selected CTA, MRA, and IVW (T1-weighted) images were then reviewed by two independent raters blinded to the other measurements in random order. Measurements were made in a plane perpendicular to the lumen on each modality. MRA and IVW measurements were compared to CTA, to determine which more accurately matched the degree of stenosis. Results: 18 patients with 33 intracranial atherosclerotic stenoses were included. Relative to CTA, IVW had 40% less variance than MRA (p = .004). IVW had a significant...
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BackgroundIntracranial aneurysms (IAs) are common in the population and current imaging-based rupture risk assessment needs to be refined. We aimed to use four-dimensional CT angiography (4D-CTA) to investigate the associations of... more
BackgroundIntracranial aneurysms (IAs) are common in the population and current imaging-based rupture risk assessment needs to be refined. We aimed to use four-dimensional CT angiography (4D-CTA) to investigate the associations of irregular pulsation of IAs with conventional risk factors and the estimated rupture risk.MethodsOne hundred and five patients with 117 asymptomatic IAs underwent 4D-CTA. Geometric and morphologic parameters were measured and the presence of irregular pulsation (defined as a temporary focal protuberance ≥1 mm on more than three successive frames) was identified on 4D-CTA movies. One- and 5 year aneurysm rupture risk were estimated using UCAS and PHASES calculators. Univariate and multivariate analyses were performed to investigate the conventional risk factors associated with irregular pulsation.ResultsIrregular pulsation was observed in 41.0% (48/117) of IAs. Aneurysm size (OR=1.380, 95% CI 1.165 to 1.634), irregular shape (OR=3.737, 95% CI 1.108 to 12.608...
The utility and necessity of pretreatment with intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remains an issue of strong debate. This study aims to compare the outcomes of bridging thrombolysis (BT, IVT+MT) with direct... more
The utility and necessity of pretreatment with intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remains an issue of strong debate. This study aims to compare the outcomes of bridging thrombolysis (BT, IVT+MT) with direct MT (d-MT) after large vessel ischemic stroke based on the most up-to-date evidence. MEDLINE, EMBASE, Scopus, and the Cochrane Library from January 2017 to June 2020 were searched for studies that directly compared the outcomes of the 2 strategies. Methodological quality was assessed using the Quality in Prognostic Studies tool. Combined estimates of odds ratios (ORs) of BT versus d-MT were derived. Multiple subgroup analyses were performed, especially for IVT-eligible patients. Thirty studies involving 7191 patients in the BT group and 4891 patients in the d-MT group were included. Methodological quality was generally high. Compared with patients in the d-MT group, patients in the BT group showed significantly better functional independence (modifi...
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Background and Purpose: Aneurysmal wall enhancement (AWE) on vessel wall magnetic resonance imaging (VW-MRI) has been described as a new imaging biomarker of unstable unruptured intracranial aneurysms (UIAs). Previous studies of... more
Background and Purpose: Aneurysmal wall enhancement (AWE) on vessel wall magnetic resonance imaging (VW-MRI) has been described as a new imaging biomarker of unstable unruptured intracranial aneurysms (UIAs). Previous studies of symptomatic UIAs are limited due to small sample sizes and lack of AWE quantification. Our study aims to investigate whether qualitative and quantitative assessment of AWE can differentiate symptomatic and asymptomatic UIAs. Methods: Consecutive patients with UIAs were prospectively recruited for vessel wall magnetic resonance imaging at 3T from October 2014 to October 2019. UIAs were categorized as symptomatic if presenting with sentinel headache or oculomotor nerve palsy directly related to the aneurysm. Evaluation of wall enhancement included enhancement pattern (0=none, 1=focal, and 2=circumferential) and quantitative wall enhancement index (WEI). Univariate and multivariate analyses were used to identify the parameters associated with symptoms. Results:...
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BACKGROUND India has a high traumatic brain injury (TBI) burden and intracranial pressure monitoring (ICP) remains controversial but some patients may benefit. OBJECTIVE To examine the association between ICP monitor placement and... more
BACKGROUND India has a high traumatic brain injury (TBI) burden and intracranial pressure monitoring (ICP) remains controversial but some patients may benefit. OBJECTIVE To examine the association between ICP monitor placement and outcomes, and identify Indian patients with severe TBI who benefit from ICP monitoring METHODS We conducted a secondary analysis of a prospective cohort study at a level 1 Indian trauma center. Patients over 18 yr with severe TBI (admission Glasgow coma scale score
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The optimal diagnostic evaluation for patients with angiographically negative subarachnoid hemorrhage (AN-SAH) remains controversial. To assess the utilization rate and diagnostic yield of imaging tests routinely obtained in identifying a... more
The optimal diagnostic evaluation for patients with angiographically negative subarachnoid hemorrhage (AN-SAH) remains controversial. To assess the utilization rate and diagnostic yield of imaging tests routinely obtained in identifying a structural cause for AN-SAH. In this retrospective multicenter study, consecutive adult patients admitted with nontraumatic, AN-SAH between 01/2010 and 12/2015 were included. Patients with intraparenchymal, subdural, or epidural hematomas in addition to SAH were excluded. Outcomes studied included utilization rate, diagnostic yield, and median time from admission for the following imaging tests: initial computed tomography angiography (CTA) and digital subtraction angiography (DSA), brain and cervical spine magnetic resonance imaging (MRI), and any repeat DSA or CTA performed either during initial admission or at long-term follow-up. A total of 752 patients were included (mean age, 53 yr; 54% male). Initial CTA and DSA were performed in 89% and 100...
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To develop a quantitative intracranial artery measurement technique to extract comprehensive artery features from time-of-flight MR angiography (MRA). By semiautomatically tracing arteries based on an open-curve active contour model in a... more
To develop a quantitative intracranial artery measurement technique to extract comprehensive artery features from time-of-flight MR angiography (MRA). By semiautomatically tracing arteries based on an open-curve active contour model in a graphical user interface, 12 basic morphometric features and 16 basic intensity features for each artery were identified. Arteries were then classified as one of 24 types using prediction from a probability model. Based on the anatomical structures, features were integrated within 34 vascular groups for regional features of vascular trees. Eight 3D MRA acquisitions with intracranial atherosclerosis were assessed to validate this technique. Arterial tracings were validated by an experienced neuroradiologist who checked agreement at bifurcation and stenosis locations. This technique achieved 94% sensitivity and 85% positive predictive values (PPV) for bifurcations, and 85% sensitivity and PPV for stenosis. Up to 1,456 features, such as length, volume,...
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High-resolution vessel wall MRI (vwMRI) of the intracranial arteries is an emerging diagnostic imaging technique with the goal of evaluating vascular pathology. vwMRI sequences have high spatial resolution and directly image the vessel... more
High-resolution vessel wall MRI (vwMRI) of the intracranial arteries is an emerging diagnostic imaging technique with the goal of evaluating vascular pathology. vwMRI sequences have high spatial resolution and directly image the vessel wall by suppressing blood signal. With vwMRI, it is possible to identify distinct morphologic and enhancement patterns of atherosclerosis that can provide important information about stroke etiology and recurrence risk. We present a review of vwMRI research in relation to intracranial atherosclerosis, with a focus on the relationship between ischemic stroke and atherosclerotic plaque T1 post-contrast enhancement or plaque/vessel wall morphology. The goal of this review is to provide readers with the most current understanding of the reliability, incidence, and importance of specific vwMRI findings in intracranial atherosclerosis, to guide their interpretation of vwMRI research, and help inform clinical interpretation of vwMRI. We will also provide a translational perspective on the existing vwMRI literature and insight into future vwMRI research questions and objectives. With increased use of high field strength MRI, powerful gradients, and improved pulse sequences, vwMRI will become standard-of-care in the diagnosis and prognosis of patients with cerebrovascular disease, making a firm grasp of its strengths and weakness important for neuroimagers.
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Background Carotid intraplaque hemorrhage (IPH) seen on vessel wall MRI is associated with an increased risk of stroke or transient ischemic attack, as are microembolic signals (MES) detected by transcranial Doppler (TCD). We sought to... more
Background Carotid intraplaque hemorrhage (IPH) seen on vessel wall MRI is associated with an increased risk of stroke or transient ischemic attack, as are microembolic signals (MES) detected by transcranial Doppler (TCD). We sought to examine the association between IPH and MES in acute stroke patients with symptomatic carotid atherosclerosis. Methods Through a retrospective chart review, we included patients from 2011 to 2013 with acute ischemic stroke due to carotid atherosclerosis of varying stenosis who had both 3D volumetric MRI of the neck and TCD emboli monitoring. Results Twenty-four patients met the inclusion criteria. Mean time from stroke to MRI was 1.4 ± 1.9 days and to TCD was 2.6 ± 2.4 days. MES was seen in 10 patients (42%) and IPH was present in seven patients (29%), but we did not find a relationship between MES and IPH ( p = 0.64). Conclusion In patients with recent acute ischemic stroke attributed to carotid atherosclerosis, we did not detect an association betwe...
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Although diffusion-weighted imaging (DWI) has become a mainstay in modern brain imaging, it remains less utilized in the evaluation of the spinal cord. Many studies have shown promise in using DWI and diffusion-tensor imaging (DTI) for... more
Although diffusion-weighted imaging (DWI) has become a mainstay in modern brain imaging, it remains less utilized in the evaluation of the spinal cord. Many studies have shown promise in using DWI and diffusion-tensor imaging (DTI) for evaluation of the spinal cord; however, application has been stalled by technical obstacles and artifacts, and questions remain regarding its clinical utility on an individual examination level. This review discusses the background, concepts, and technical aspects of DWI and DTI, specifically for imaging of the spinal cord. The clinical and investigational applications of spinal cord DTI, as well as the practical difficulties and limitations of DWI and DTI for the evaluation of the spinal cord are examined.
This study differentiates cerebral fat embolism (CFE) and diffuse axonal injury (DAI) on diffusion-weighted magnetic resonance imaging (DWI) and T2*-weighted magnetic resonance imaging. Consecutive CFE and DAI cases were retrospectively... more
This study differentiates cerebral fat embolism (CFE) and diffuse axonal injury (DAI) on diffusion-weighted magnetic resonance imaging (DWI) and T2*-weighted magnetic resonance imaging. Consecutive CFE and DAI cases were retrospectively selected. Hemorrhages were characterized by number, size/shape, and distribution, whereas DWI lesions by pattern. The number of hemorrhages was compared using the Mann-Whitney test with adjustment for multiple comparisons, whereas DWI abnormality was compared using Fisher exact test. Seven CFE and 20 DAI patients were included. Cerebral fat embolism had significantly more hemorrhages than DAI (mean, 670 ± 407 vs 136 ± 87; P = 0.01), particularly in the frontal (P = 0.025), parietal (P = 0.002), and occipital lobes (P = 0.01), the corpus callosum (P = 0.01), and cerebellum (P = 0.01). Cerebral fat embolism microhemorrhages were punctate/round, whereas DAI hemorrhages were small/medium sized (P < 0.001) and linear (P = 0.001). On DWI, DAI typically had few scattered abnormalities, whereas CFE had confluent abnormalities (P < 0.05). Magnetic resonance imaging can differentiate CFE from DAI. Cerebral fat embolism demonstrates more hemorrhages. Larger or linear hemorrhages favor DAI. Diffuse confluent diffusion restriction favors CFE, whereas few scattered foci favor DAI.
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Intracranial aneurysms are heterogeneous in histopathology and imaging appearance. The biological behavior of different types of aneurysms is now known to depend on the structure and physiology of the aneurysm wall itself in addition to... more
Intracranial aneurysms are heterogeneous in histopathology and imaging appearance. The biological behavior of different types of aneurysms is now known to depend on the structure and physiology of the aneurysm wall itself in addition to intraluminal flow and other luminal features. Aneurysm wall structure and imaging markers of physiology such as aneurysm wall enhancement have been assessed in many prior investigations using conventional-resolution MRI. Recently, high-resolution vessel wall imaging (HR-VWI) techniques with MRI have been introduced. Reports of findings on high-resolution imaging have already emerged for many types of aneurysms demonstrating detailed characterization of wall enhancement, thickness, and components, but many questions remain unexplored. This review discusses the key HR-VWI literature to date. Aneurysm wall findings on conventional-resolution MRI are also discussed as these may help one understand the potential utility and findings on HR-VWI for various ...
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Cerebrovascular diseases have traditionally been classified, diagnosed and managed based on their luminal characteristics. However, over the past several years, several advancements in MRI techniques have ushered in high-resolution vessel... more
Cerebrovascular diseases have traditionally been classified, diagnosed and managed based on their luminal characteristics. However, over the past several years, several advancements in MRI techniques have ushered in high-resolution vessel wall imaging (HR-VWI), enabling evaluation of intracranial vessel wall pathology. These advancements now allow us to differentiate diseases which have a common angiographic appearance but vastly different natural histories (i.e. moyamoya versus atherosclerosis, reversible cerebral vasoconstriction syndrome versus vasculitis, stable versus unstable intracranial aneurysms). In this review, we detail the anatomical, histopathological and imaging characteristics of various intracranial steno-occlusive diseases and types of intracranial aneurysms and describe the role that HR-VWI can play in diagnosis, risk stratification and treatment.
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Diffusion tensor imaging (DTI) is increasingly investigated as a potential diagnostic and prognostic tool for symptomatic degenerative cervical pathology; however, it is yet to be validated for this purpose. To investigate the association... more
Diffusion tensor imaging (DTI) is increasingly investigated as a potential diagnostic and prognostic tool for symptomatic degenerative cervical pathology; however, it is yet to be validated for this purpose. To investigate the association of pre-operative DTI signal changes and post-operative outcomes in patients with cervical spondylotic myelopathy (CSM). We performed a systematic literature review using PubMed for clinical studies using DTI in adults undergoing operative management for CSM. Data on pre-operative clinical status, pre-operative DTI metrics and post-operative clinical outcomes were abstracted. Pre-operative DTI parameters were correlated with pre-operative severity and post-operative outcomes and pooled across studies. Nine studies met inclusion criteria for 238 patients that underwent operative management with mean follow-up time 310 days. Higher pre-operative fractional anisotropy (FA) at the level of maximal compression correlates strongly with higher pre-operativ...
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Accurate and timely diagnosis of intracranial vasculopathies is important due to significant risk of morbidity with delayed and/or incorrect diagnosis both from the disease process as well as inappropriate therapies. Conventional vascular... more
Accurate and timely diagnosis of intracranial vasculopathies is important due to significant risk of morbidity with delayed and/or incorrect diagnosis both from the disease process as well as inappropriate therapies. Conventional vascular imaging techniques for analysis of intracranial vascular disease provide limited information since they only identify changes to the vessel lumen. New advanced MR intracranial vessel wall imaging (IVW) techniques can allow direct characterisation of the vessel wall. These techniques can advance diagnostic accuracy and may potentially improve patient outcomes by better guided treatment decisions in comparison to previously available invasive and non-invasive techniques. While neuroradiological expertise is invaluable in accurate examination interpretation, clinician familiarity with the application and findings of the various vasculopathies on IVW can help guide diagnostic and therapeutic decision-making. This review article provides a brief overview of the technical aspects of IVW and discusses the IVW findings of various intracranial vasculopathies, differentiating characteristics and indications for when this technique can be beneficial in patient management.
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Dual-energy computed tomography (DECT) allows image reconstruction along a spectrum of virtual monochromatic energy levels. We sought to determine the optimal energy level(s) for viewing supratentorial brain and posterior fossa and... more
Dual-energy computed tomography (DECT) allows image reconstruction along a spectrum of virtual monochromatic energy levels. We sought to determine the optimal energy level(s) for viewing supratentorial brain and posterior fossa and compare those to polychromatic conventional CT (CCT). Furthermore, we compared 2 groups scanned with separate DECT imaging protocols. In addition, we quantify the radiation dose of DECT versus CCT. Forty-four nonacute patients underwent noncontrast DECT and recent CCT on the same scanner. Dual-energy CT images of the head were reconstructed at 5 keV intervals from 50 to 100 keV and randomized with CCT for blinded reader analysis. Evaluation of gray-white matter differentiation, posterior fossa artifact, and overall image noise was performed in consensus using a 5-point scale. In addition, the CTDIvol was compared with CCT examinations. Optimal monochromatic viewing levels in evaluating gray-white matter differentiation were 50 to 55 keV and 50 to 60 keV, using regular-dose DECT (R-DECT) and low-dose DECT (L-DECT), respectively. The optimal levels for mitigating posterior fossa artifacts were 80 to 100 keV utilizing both R-DECT and L-DECT, whereas the optimal viewing levels for improved overall image noise were 60 to 65 keV and 65 to 70 keV for R-DECT and L-DECT, respectively. Readers favored both DECT techniques over CCT. The CTDIvol for DECT was 10% and 37% lower than CCT without a statistically significant reduction in image quality. Optimized noncontrast DECT compared favorably to CCT, with a significant dose reduction benefit.
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Although treatment guidelines are well established for symptomatic patients with greater than 69% carotid stenosis on catheter angiography, optimal management of lower degrees of stenosis remain unclear. Vessel wall MR imaging of the... more
Although treatment guidelines are well established for symptomatic patients with greater than 69% carotid stenosis on catheter angiography, optimal management of lower degrees of stenosis remain unclear. Vessel wall MR imaging of the carotid arteries has proved helpful in the evaluation of plaque burden and vulnerable plaque characteristics, and in stratifying risk in low-grade carotid stenosis. This article discusses the pathophysiology and imaging of atherosclerotic plaques resulting in low-grade carotid stenosis, and the corresponding stroke risk and association with plaque elsewhere in the cardiovascular system.
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Fat necrosis (FN) of the breast is a benign nonsuppurative inflammatory process of the adipose tissue. The radiologic appearance ranges from benign to suspicious for malignancy; therefore, it is very important to know the distinguishing... more
Fat necrosis (FN) of the breast is a benign nonsuppurative inflammatory process of the adipose tissue. The radiologic appearance ranges from benign to suspicious for malignancy; therefore, it is very important to know the distinguishing radiologic features of FN on different modalities. Mammography is more helpful in identifying FN than ultrasonography in most of the cases, and MRI may also be used to rule out malignancy as an adjunct to mammography and sonography. Even when modern diagnostic modalities are used, biopsy may still be unavoidable for some cases. In conclusion, an accurate history and familiarity with the radiologic findings are crucial to recognizing FN and avoiding unnecessary interventions.
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PURPOSE/AIM The purpose is to educate the viewer on the pathophysiology, clinical markers and multimodality imaging characteristics of cerebral vasculitis, including digital subtraction angiography (DSA), conventional MRI/MRA, contrast... more
PURPOSE/AIM The purpose is to educate the viewer on the pathophysiology, clinical markers and multimodality imaging characteristics of cerebral vasculitis, including digital subtraction angiography (DSA), conventional MRI/MRA, contrast susceptibility perfusion (DSC), susceptibility weighted imaging (SWI) and black blood MR imaging (BBMR). We will also show the temporal evolution of conventional and advanced imaging findings of CNS vasculitis with appropriate therapy. CONTENT ORGANIZATION A. Pathophysiology and clinical markers of CNS vasculitis B. Sample cases -DSA -CTA -conventional MRI/MRA -DSC -SWI -BBMR C. Longitudinal imaging findings of CNS vasculitis on therapy D. Limitations of imaging for CNS vasculitis SUMMARY DSA is the gold standard imaging exam for CNS vasculitis. However, a multimodal approach combined with clinical markers is frequently necessary for correct diagnosis and complication evaluation. We will present cases of CNS vasculitis, discussing clinical markers and...
PURPOSE/AIM To familiarize the viewer with the technique of performing intracranial black blood MRA (BBMR). To review the pathophysiology of four disease entities that affect the intracranial arteries and explain how it relates to the... more
PURPOSE/AIM To familiarize the viewer with the technique of performing intracranial black blood MRA (BBMR). To review the pathophysiology of four disease entities that affect the intracranial arteries and explain how it relates to the black blood MRA features of each. CONTENT ORGANIZATION - Technique - Pathophysiology and imaging features of atherosclerosis, arterial dissection, RCVS, and vasculitis - Cases - Artifacts & Pitfalls SUMMARY Familiarity with the underlying pathophysiology helps explain the BBMR features of several intracranial arterial disease entities. BBMR can evaluate vessel wall characteristics while luminal imaging (MRA, CTA, DSA) does not, which can help differentiate causes for intracranial arterial stenosis. Differentiating features include patterns and signal characteristics of vessel wall involvement, presence, pattern, and degree of enhancement, and lesion distribution. This technique could limit the number of invasive diagnostic procedures that a patient und...
Intracranial atherosclerotic disease (ICAD) accounts for 9-15% of ischemic stroke in the United States. Although highly stenotic ICAD accounts for most of the strokes, it is assumed that nonstenotic ICAD (nICAD) can result in stroke,... more
Intracranial atherosclerotic disease (ICAD) accounts for 9-15% of ischemic stroke in the United States. Although highly stenotic ICAD accounts for most of the strokes, it is assumed that nonstenotic ICAD (nICAD) can result in stroke, despite being missed on standard luminal imaging modalities. We describe a patient with nICAD who suffered recurrent thromboembolic stroke and TIA but had a negative conventional stroke workup. As a result, they were referred for high-resolution magnetic resonance imaging (HR-MRI) of the arterial vessel wall, which identified a nonstenotic plaque with multiple high-risk features, identifying it as the etiology of the patient's thromboembolic events. The diagnosis resulted in a transition from anticoagulation to antiplatelet therapy, after which the patient's clinical events resolved. HR-MRI is an imaging technique that has the potential to guide medical management for patients with ischemic stroke, particularly in cryptogenic stroke.
I n the United States, autopsy rates have fallen precipitously since the 1970s to 4.3% for natural deaths occurring both inside and outside of the hospital (1). This decrease is mirrored worldwide. Reasons for the decline have long been... more
I n the United States, autopsy rates have fallen precipitously since the 1970s to 4.3% for natural deaths occurring both inside and outside of the hospital (1). This decrease is mirrored worldwide. Reasons for the decline have long been debated and include diagnostic overconfidence, physician reluctance to pursue consent for autopsy, family reluctance to grant permission for autopsy, lack of regulatory rate requirements, and budgetary constraints. Despite this underutilization, autopsy remains the gold standard for determining the cause of death. It offers benefit for education, research, and quality improvement, particularly as applied to diagnostic accuracy and the potential to improve patient care. Although major diagnostic discrepancies have decreased at a relative rate of 19.4% per decade, the median error rate remains sufficiently high (23.5%) to warrant encouraging ongoing use of autopsies (2). In recent years, there has been increased interest in using radio-logic imaging te...
Although studies have attempted to differentiate intracranial vascular disease using vessel wall magnetic resonance imaging (VWI), none have incorporated multicontrast imaging. This study uses T1- and T2-weighted VWI to differentiate... more
Although studies have attempted to differentiate intracranial vascular disease using vessel wall magnetic resonance imaging (VWI), none have incorporated multicontrast imaging. This study uses T1- and T2-weighted VWI to differentiate intracranial vasculopathies. We retrospectively reviewed patients with clinically defined intracranial vasculopathies causing luminal stenosis/irregularity who underwent VWI studies. Two blinded experts evaluated T1 precontrast and postcontrast and T2-weighted VWI characteristics, including the pattern of wall thickening; presence, pattern, and intensity of postcontrast enhancement; and T2 signal characteristics. Twenty-one cases of atherosclerosis (intracranial atherosclerotic disease [ICAD]), 4 of reversible cerebral vasoconstriction syndrome, and 4 of vasculitis were identified, with a total of 118 stenotic lesions (81 ICAD, 22 reversible cerebral vasoconstriction syndrome, and 15 vasculitic lesions). There was substantial to excellent inter-reader agreement for the assessment of lesional T2 hyperintensity (κ=0.80), pattern of wall thickening (κ=0.87), presence (κ=0.90), pattern (κ=0.73), and intensity (κ=0.77) of enhancement. ICAD lesions were significantly more likely to have eccentric wall involvement (90.1%) than reversible cerebral vasoconstriction syndrome (8.2%; P<0.001) and vasculitic lesions (6.7%; P<0.001) and were also more likely to have T2 hyperintensity present than the other 2 vasculopathies (79% versus 0%; P<0.001). There were also significant differences in the presence, intensity, and pattern of enhancement between all lesion types. Combining T1 and T2 VWI increased the sensitivity of VWI in differentiating ICAD from other vasculopathies from 90.1% to 96.3%. Multicontrast VWI can be a complementary tool for intracranial vasculopathy differentiation, which often leads to more invasive workups when reversible cerebral vasoconstriction syndrome and vasculitis are in the differential diagnosis.
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ABSTRACT We present a 20-year-old patient with low back pain and lower extremity weakness, who was diagnosed with lumbar spinal cord glioblastoma multiforme (GBM) in further workup. The tumor gradually extended upward, and within 11... more
ABSTRACT We present a 20-year-old patient with low back pain and lower extremity weakness, who was diagnosed with lumbar spinal cord glioblastoma multiforme (GBM) in further workup. The tumor gradually extended upward, and within 11 months after the first presentation, he developed multiple brain metastases.