Wed Sep 04, 2019 18:00
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Currently, accurate and reproducible spinal cord GM segmentation remains challenging and a noninvasive broadly accepted reference standard for spinal cord GM measurements is still a matter of ongoing discussion. Our aim was to assess the reproducibility and accuracy of cervical spinal cord GM and WM cross-sectional area measurements using averaged magnetization inversion recovery acquisitions images and a fully-automatic postprocessing segmentation algorithm. MATERIALS AND...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Quantitative imaging biomarkers have not been established for the diagnosis of spinal canal stenosis. This work aimed to lay the groundwork to establish such biomarkers by leveraging the developments in machine learning and medical imaging informatics. MATERIALS AND METHODS:Machine learning algorithms were trained to segment lumbar spinal canal areas on axial views and intervertebral discs on sagittal views of lumbar MRIs. These were used to measure spinal canal areas at each...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Volumetric high-resolution heavily T2-weighted imaging or time-resolved contrast-enhanced MRA is used in the detection and characterization of spinal vascular malformations, though inherent trade-offs can affect their overall sensitivity and accuracy. We compared the efficacy of volumetric high-resolution heavily T2-weighted and time-resolved contrast-enhanced images in spinal vascular malformation diagnosis and feeder characterization and assessed whether a combined evaluation...
Wed Sep 04, 2019 18:00
SUMMARY:Insular epilepsy is underdiagnosed and accounts for a number of failed operations. Identifying insular target lesions on MR imaging can help guide intracranial electroencephalography and improve the outcome of surgery. In this study, we present a novel method of exploring the insular region for subtle lesions on 3D MR imaging by MPR postprocessing of slices in oblique reference planes. Using this method, we retrospectively reviewed presurgical MRIs that were initially considered to have normal...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Recurrent middle ear cholesteatomas are commonly preoperatively assessed using MR imaging (non-EPI-DWI) and CT. Both modalities are used with the aim of distinguishing scar tissue from cholesteatoma and determining the extent of bone erosions. Inflammation and scar tissue associated with the lesions might hamper a proper delineation of the corresponding extensions on CT images. Using surgical findings as the criterion standard, we assessed the recurrent middle ear cholesteatoma...
Wed Sep 04, 2019 18:00
SUMMARY:Cerebral hyperperfusion syndrome is a serious complication of endovascular angioplasty and stent placement for long-standing intracranial stenosis, resulting in neurologic dysfunction, seizure, or reperfusion hemorrhage. Rigorous control of blood pressure is commonly used in the perioperative period to prevent cerebral hyperperfusion syndrome, but the optimal blood pressure is often arbitrary. We describe the angiographic features that reflect impaired cerebral autoregulation and microvascular...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Contrast-enhanced T1-weighted sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) with the delay alternating with nutation for tailored excitation (DANTE) pulse could suppress the blood flow signal and provide a higher contrast-to-noise ratio of enhancing lesion-to-brain parenchyma than the MPRAGE sequence. The purpose of our study was to evaluate the usefulness of SPACE with DANTE compared with MPRAGE for detecting brain...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Huntington disease is a devastating genetic neurodegenerative disorder for which no effective treatment is yet available. Although progressive striatal atrophy is its pathologic hallmark, concomitant cortical deterioration is assumed to occur, but it is poorly characterized. Our objective was to study the loss of cortical integrity and its association with clinical indicators throughout the course of the disease. MATERIALS AND METHODS:Using a cohort of 39 patients with Huntington...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Gadolinium enhanced MRI is routinely used for follow-up of patients with multiple sclerosis. Our aim was to evaluate whether enhancing multiple sclerosis lesions on follow-up MR imaging can be detected by visual assessment of unenhanced double inversion recovery and FLAIR sequences. MATERIALS AND METHODS:A total of 252 consecutive MRIs in 172 adult patients with a known diagnosis of multiple sclerosis were reviewed. The co-presence or absence of associated double inversion...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Non-contrast-enhanced MRA techniques have experienced a renaissance due to the known correlation between the use of gadolinium-based contrast agents and the development of nephrogenic systemic fibrosis and the deposition of gadolinium in some brain regions. The purpose of this study was to assess the diagnostic performance of ungated non-contrast-enhanced radial quiescent-interval slice-selective MRA of the extracranial supra-aortic arteries in comparison with conventional...
Wed Sep 04, 2019 18:00
SUMMARY:Pericortical enhancement on postcontrast FLAIR images is a marker for subtle leptomeningeal blood-brain barrier leakage. We explored the optimal FLAIR sequence parameters for the detection of low gadolinium concentrations within the CSF. On the basis of phantom experiments and human in vivo data, we showed that detection of subtle pericortical enhancement can be facilitated by using a relatively long TE. Future studies should choose their FLAIR sequence parameters carefully when assessing...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Intraocular silicone oil injection has been used to treat complicated retinal detachments, and recently its retrolaminar and intracranial migration has been reported. The purpose of this study was to document the prevalence of posterior migration of intraocular silicone oil on head CT and describe the clinical and radiologic findings. MATERIALS AND METHODS:This retrospective study included 57 patients with intraocular silicone oil injection who underwent unenhanced head CT...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Zero TE–MRA is less sensitive to field heterogeneity, complex flow, and acquisition noise. This study aimed to prospectively validate the feasibility of zero TE–MRA for cerebrovascular diseases assessment, compared with TOF-MRA. MATERIALS AND METHODS:Seventy patients suspected of having cerebrovascular disorders were recruited. Sound levels were estimated for each MRA subjectively and objectively in different modes. MRA image quality was estimated by 2 neuroradiologists. The...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Tumor recurrence is difficult to predict in patients receiving laser ablation for intracranial malignancy. We assessed the efficacy of the initial area under the time-to-signal intensity curve at 60 seconds (iAUC60) from dynamic contrast-enhanced MR imaging in predicting progression-free survival in patients with brain metastases following laser interstitial thermal therapy. MATERIALS AND METHODS:The study population was a consecutive series of patients undergoing laser interstitial...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:The Bayesian probabilistic method has shown promising results to offset noise-related variability in perfusion analysis. Using CTP, we aimed to find optimal Bayesian-estimated thresholds based on multiparametric voxel-level models to estimate the ischemic core in patients with acute ischemic stroke. MATERIALS AND METHODS:Patients with anterior circulation acute ischemic stroke who had baseline CTP and achieved successful recanalization were included. In a subset of patients,...
Wed Sep 04, 2019 18:00
SUMMARY:The aim of this study was to describe the feasibility, technique, and safety of distal transradial access in the anatomic snuffbox for diagnostic cerebral angiography. A retrospective review of diagnostic cerebral angiograms obtained during a 6-month period with distal transradial access was performed. Thirty-four successful procedures were performed via distal transradial access. There were 4 failed attempts. This single-center experience using distal transradial access suggests that this...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:4D CT angiography is increasingly used in clinical practice for the assessment of different neurovascular disorders. Optimized processing of 4D-CTA is crucial for diagnostic interpretation because of the large amount of data that is generated. A color-mapping method for 4D-CTA is presented for improved and enhanced visualization of the cerebral vasculature hemodynamics. This method was applied to detect cranial AVFs. MATERIALS AND METHODS:All patients who underwent both 4D-CTA...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:The presence of IPH is considered the most dangerous feature because it is significantly associated with clinical ipsilateral cerebrovascular events. Our aim was to explore the characterization of plaque with CT in symptomatic subjects with bilateral intraplaque hemorrhage. MATERIALS AND METHODS:Three-hundred-forty-three consecutive patients with recent anterior circulation ischemic events (<2 weeks) and CT of the carotid arteries (performed within 14 days of the cerebrovascular...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Fetuses with isolated nonsevere ventriculomegaly (INSVM) are at risk of presenting neurodevelopmental delay. However, the currently used clinical parameters are insufficient to select cases with high risk and determine whether subtle changes in brain development are present and might be a risk factor. The aim of this study was to perform a comprehensive evaluation of cortical development in INSVM by magnetic resonance (MR) imaging and assess its association with neonatal neurobehavior....
Wed Sep 04, 2019 18:00
A Persistent Foramen of Huschke: A Small Road to Misery in Necrotizing External Otitis [HEAD & NECK]
BACKGROUND AND PURPOSE:Necrotizing external otitis is a serious complication of external otitis with different spreading patterns. A persistent foramen of Huschke is a dehiscence located antero-inferior in the osseous external ear canal and posterior-medial to the temporomandibular joint. This dehiscence can facilitate extension of infection in an anterior pattern next to classic spread along the fissures of Santorini. The aim of this study was to define the prevalence and size of a persistent foramen...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Image-based classification of lower-grade glioma molecular subtypes has substantial prognostic value. Diffusion tensor imaging has shown promise in lower-grade glioma subtyping but currently requires lengthy, nonstandard acquisitions. Our goal was to investigate lower-grade glioma classification using a machine learning technique that estimates fractional anisotropy from accelerated diffusion MR imaging scans containing only 3 diffusion-encoding directions. MATERIALS AND METHODS:Patients...
Wed Sep 04, 2019 18:00
SUMMARY:Zero TE MR imaging is a novel technique that achieves a near-zero time interval between radiofrequency excitation and data acquisition, enabling visualization of short-T2 materials such as cortical bone. Zero TE offers a promising radiation-free alternative to CT with rapid, high-resolution, silent, and artifact-resistant imaging, as well as the potential for "pseudoCT" reconstructions. In this report, we will discuss our preliminary experience with zero TE, including technical principles...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:The percentage signal recovery in non-leakage-corrected (no preload, high flip angle, intermediate TE) DSC-MR imaging is known to differ significantly for glioblastoma, metastasis, and primary CNS lymphoma. Because the percentage signal recovery is influenced by preload and pulse sequence parameters, we investigated whether the percentage signal recovery can still differentiate these common contrast-enhancing neoplasms using a DSC-MR imaging protocol designed for relative CBV...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Validation of diffusion-weighted images obtained on 0.35T MR imaging in Malawi has facilitated meaningful review of previously unreported findings in cerebral malaria. Malawian children with acute cerebral malaria demonstrated restricted diffusion on brain MR imaging, including an unusual pattern of restriction isolated to the subcortical white matter. We describe the patterns of diffusion restriction in cerebral malaria and further evaluate risk factors for and outcomes associated...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Working memory impairment is one of the most troubling and persistent symptoms after mild traumatic brain injury (MTBI). Here we investigate how working memory deficits relate to detectable WM microstructural injuries to discover robust biomarkers that allow early identification of patients with MTBI at the highest risk of working memory impairment. MATERIALS AND METHODS:Multi-shell diffusion MR imaging was performed on a 3T scanner with 5 b-values. Diffusion metrics of fractional...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:The Woven EndoBridge device proved its effectiveness in the treatment of ruptured and unruptured intracranial aneurysms as a stand-alone device. Before 2016, Woven EndoBridge deployment required at least a 0.021-inch microcatheter. In 2016, a smaller device, the Woven EndoBridge 17 with finer size increments that used a 0.017-inch microcatheter, was introduced. We retrospectively analyzed our initial and follow-up results with the Woven EndoBridge 17 in ruptured and unruptured...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:4D-DSA allows time-resolved 3D imaging of the cerebral vasculature. The aim of our study was to evaluate this method in comparison with the current criterion standard 3D-DSA by qualitative and quantitative means using computational fluid dynamics. MATERIALS AND METHODS:3D- and 4D-DSA datasets were acquired in patients with cerebral aneurysms. Computational fluid dynamics analysis was performed for all datasets. Using computational fluid dynamics, we compared 4D-DSA with 3D-DSA...
Wed Sep 04, 2019 18:00
BACKGROUND AND PURPOSE:Intrasaccular flow diversion offers a promising treatment option for complex bifurcation aneurysms. The purpose of this study was to compare the flow conditions between successfully occluded and incompletely occluded aneurysms treated with intrasaccular devices. MATERIALS AND METHODS:The hemodynamics in 18 completely occluded aneurysms after treatment with intrasaccular devices was compared against 18 that were incompletely occluded at follow-up. Hemodynamic and geometric...
Wed Sep 04, 2019 18:00
Publication date: Available online 3 September 2019Source: Academic RadiologyAuthor(s): V Linehan, J Ramlackhansingh, A Hartery, R GullipalliRational and ObjectivesDespite the increasing use of point of care ultrasound (POCUS) across many specialities, ultrasound training in Canadian medical schools is limited. At our center, the student Radiology Interest Group (RIG) has addressed this learning need by hosting an annual workshop for diagnostic ultrasound to improve student competency in POCUS.Materials...
Wed Sep 04, 2019 17:46
Publication date: 15 November 2019Source: NeuroImage, Volume 202Author(s): Essam A. Rashed, Jose Gomez-Tames, Akimasa HirataAbstractThe development of personalized human head models from medical images has become an important topic in the electromagnetic dosimetry field, including the optimization of electrostimulation, safety assessments, etc. Human head models are commonly generated via the segmentation of magnetic resonance images into different anatomical tissues. This process is time consuming...
Wed Sep 04, 2019 17:41
Publication date: 15 November 2019Source: NeuroImage, Volume 202Author(s): Luis M. Colon-Perez, Kristen R. Ibanez, Mallory Suarez, Kristin Torroella, Kelly Acuna, Edward Ofori, Yona Levites, David E. Vaillancourt, Todd E. Golde, Paramita Chakrabarty, Marcelo FeboAbstractExtracellular β-amyloid (Aβ) plaque deposits and inflammatory immune activation are thought to alter various aspects of tissue microstructure, such as extracellular free water, fractional anisotropy and diffusivity, as well as the...
Wed Sep 04, 2019 17:41
Presenting a case of neuroblastoma with sutural metastases. DAMS unplugged is YouTube series by DAMS team presenting clinical and integrated videosFamous Radiology Blog http://www.sumerdoc.blogspot.com TeleRad Providers at www.teleradproviders.com Mail us at sales@teleradproviders.com
Wed Sep 04, 2019 16:36
Publication date: Available online 4 September 2019Source: Ultrasound in Medicine & BiologyAuthor(s): Lauri Stenroth, Sandra Sefa, Jari Arokoski, Juha TöyräsAbstractThis study investigated the reliability of Achilles and patellar tendon cross-sectional area (CSA) measurement using ultrasound imaging (USI) and magnetic resonance imaging (MRI). Fifteen healthy adults were imaged twice on two occasions, interrupted by a tendon loading protocol. Tendon CSA segmentations were conducted by an experienced...
Wed Sep 04, 2019 15:34
Publication date: Available online 4 September 2019Source: Ultrasound in Medicine & BiologyAuthor(s): Simon Chun-Ho Yu, Eva Chun-Wai Cheung, Vivian Yee-Fong Leung, Linda Wen-Ying FungAbstractThe use of a modified energy transmission protocol and oxytocin augmentation is being proposed as a high-intensity–focused ultrasound (HIFU) treatment for uterine fibroids, to aim for an effective and well-tolerable treatment to be given as an out-patient procedure without anesthesia or sedation. The objective...
Wed Sep 04, 2019 15:34
Abstract Background Magnetic resonance imaging (MRI) of the abdomen can be especially challenging in pediatric patients because of image quality degradation from respiratory motion. Abdominal MR protocols tailored for free-breathing children can potentially improve diagnostic image quality and reduce scan time. Objective To evaluate the performance of a free-breathing...
Wed Sep 04, 2019 03:00
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