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A 72-year-old woman with Type 1 diabetes was admitted to the hospital with a left hemiparesis and hypoglycemia. Her neurological signs partially resolved with restoration of euglycemia. Magnetic resonance spectroscopy of the brain showed... more
A 72-year-old woman with Type 1 diabetes was admitted to the hospital with a left hemiparesis and hypoglycemia. Her neurological signs partially resolved with restoration of euglycemia. Magnetic resonance spectroscopy of the brain showed normal levels of N-acetyl aspartate. Three months after the hypoglycemic episode, her brain scans and N-acetyl aspartate levels remained unchanged.
OBJECTIVE The Woven Endobridge (WEB) device has been in clinical use for the treatment of brain aneurysms for the past 4 years. Observational studies to assess clinical outcome and related complications have been published. Clear evidence... more
OBJECTIVE The Woven Endobridge (WEB) device has been in clinical use for the treatment of brain aneurysms for the past 4 years. Observational studies to assess clinical outcome and related complications have been published. Clear evidence is required to better understand the safety profile of the WEB device. The authors here present a multicenter series that provides a detailed safety analysis focused on patient selection, procedural events, and technical issues of treated patients throughout the United Kingdom (UK). METHODS A nationwide password-protected database was set up to collect anonymous information across the UK (14 centers). Complications and clinical outcome were analyzed for the initial 109 patients (112 procedures). An independent root cause analysis classified the complications into groups (procedural, disease, device, ancillary device, and other). The modified Rankin Scale (mRS) was used as a marker of clinical outcome. RESULTS Each of the 109 patients had 1 aneurysm...
Ventral sulcus spinal cord arteriovenous shunts (SCAVS) are rare vascular lesions that are located outside the spinal cord, are exclusively vascularized by the anterior spinal axis, and drain exclusively through the anterior spinal vein.... more
Ventral sulcus spinal cord arteriovenous shunts (SCAVS) are rare vascular lesions that are located outside the spinal cord, are exclusively vascularized by the anterior spinal axis, and drain exclusively through the anterior spinal vein. We report the anatomical, clinical, and neuro-radiological features of SCAVS managed by our team. We conducted a retrospective study of patients with SCAVSs evaluated by the senior author of this report (GR) between 1981 and 2014. Data were collected by reviewing clinical notes and by a systematic analysis of spinal angiograms and MRI. Among 358 patients, we identified 8 patients (3 women) with ventral sulcus spinal cord arteriovenous shunts. Mean age was 30.5 years. Six patients presented with progressive neurological symptoms, and two with acute neurological symptoms related to hematomyelia. Three shunts were located in the cervical cord, four in the thoracic cord, and one at the conus medullaris; there were two nidus type A-V shunts (AVMs) and si...
The HydroSoft coil was developed as a finishing coil, ideally to be placed along the aneurysm neck to enhance intracranial aneurysm healing. The GEL THE NEC (Gaining Efficacy Long Term: Hydrosoft, an Emerging, New, Embolic Coil)... more
The HydroSoft coil was developed as a finishing coil, ideally to be placed along the aneurysm neck to enhance intracranial aneurysm healing. The GEL THE NEC (Gaining Efficacy Long Term: Hydrosoft, an Emerging, New, Embolic Coil) multicenter registry was developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We report angiographic and clinical results of this prospective registry. GEL THE NEC was performed at 27 centers in five countries. Patients aged 21-90 years with a ruptured or unruptured aneurysm 3-15 mm in size were eligible for enrollment. The following variables were obtained: demographics/comorbidities, aneurysm geometry, adjunctive devices used, proportion of patients in whom HydroSoft coils were successfully placed, and long-term angiographic outcomes (graded by an independent core laboratory using the Modified Raymond Scale), and procedure-related adverse events. Predictors of good angiographic outcome were studied using χ(2) a...
The rate of diagnosis of radiologically significant abnormalities in outpatients following requests of magnetic resonance imaging (MRI) of the brain and spine by general practitioners was compared with the rate following MRI scan requests... more
The rate of diagnosis of radiologically significant abnormalities in outpatients following requests of magnetic resonance imaging (MRI) of the brain and spine by general practitioners was compared with the rate following MRI scan requests by hospital clinicians. A similar rate of significant pathology was diagnosed in both groups in both the brain and the spine. Under carefully controlled conditions, open-access MRI scanning of the brain and spine can contribute to effective patient management.
There is a need for an accurate non-invasive diagnostic test for variant Creutzfeldt-Jakob disease (vCJD). We investigated the sensitivity and specificity of bilateral pulvinar high signal on magnetic resonance imaging (MRI) for the... more
There is a need for an accurate non-invasive diagnostic test for variant Creutzfeldt-Jakob disease (vCJD). We investigated the sensitivity and specificity of bilateral pulvinar high signal on magnetic resonance imaging (MRI) for the diagnosis of vCJD. MRI from patients with vCJD and controls (patients with suspected CJD) were analysed. Scans were reviewed on two separate occasions by two neuroradiologists and scored for the distribution of changes, and likely final diagnosis. Scans from vCJD cases were reassessed to reach a consensus on all abnormalities. We analysed 36 patients and 57 controls. vCJD patients were correctly identified based on bilateral pulvinar high signal in 29 of 36 and 32 of 36 cases on the first assessment by the two radiologists, and 32 of 36 and 31 of 36 on their second assessment. Bilateral increased pulvinar signal was identified in one of 57 and one of 57 controls on the first assessment and two of 57 and three of 57 controls on the second assessment. Thes...
The UltiPaq very soft, stretch-resistant coil is a useful new addition to the coil range available to neurointerventionists. Its highly compliant character makes it very suitable for small, ruptured aneurysms, which can easily rerupture... more
The UltiPaq very soft, stretch-resistant coil is a useful new addition to the coil range available to neurointerventionists. Its highly compliant character makes it very suitable for small, ruptured aneurysms, which can easily rerupture during coiling, and for packing the necks of larger aneurysms. It has the advantage of a rapid detachment and does not leave any tail in the parent vessel. The high density of packing achieved in these cases should result in good long-term results, but further follow up is awaited.
To test the interobserver reliability of a simple method of classifying cerebral infarcts as seen on CT brain scans, which might allow differentiation of the site and size of the infarct from infarct swelling and hemorrhagic... more
To test the interobserver reliability of a simple method of classifying cerebral infarcts as seen on CT brain scans, which might allow differentiation of the site and size of the infarct from infarct swelling and hemorrhagic transformation. Two experienced neuroradiologists independently reviewed 119 CT brain scans showing recent small to large cortical and subcortical cerebral infarcts and classified each for site and size, amount of swelling, and hemorrhagic transformation blind to clinical information. Six less experienced general radiologists in training classified 33 of the CT scans blind to clinical information. Interobserver agreement was calculated using unweighted kappa statistics. The kappa statistics between the two experienced neuroradiologists were: (a) 0.78 for site and size (95% confidence interval 0.69-0.87); (b) 0.8 for swelling (95% confidence interval, 0.68-0.92); and (c) 0.3 for hemorrhagic transformation (95% confidence interval, 0-0.77); indicating "good,&...
CT angiography (CTA) is often used for assessing patients with acute ischaemic stroke. Only limited observer reliability data exist. We tested inter- and intra-observer reliability for the assessment of CTA in acute ischaemic stroke. We... more
CT angiography (CTA) is often used for assessing patients with acute ischaemic stroke. Only limited observer reliability data exist. We tested inter- and intra-observer reliability for the assessment of CTA in acute ischaemic stroke. We selected 15 cases from the Third International Stroke Trial (IST-3, ISRCTN25765518) with various degrees of arterial obstruction in different intracranial locations on CTA. To assess inter-observer reliability, seven members of the IST-3 expert image reading panel (>5 years experience reading CTA) and seven radiology trainees (<2 years experience) rated all 15 scans independently and blind to clinical data for: presence (versus absence) of any intracranial arterial abnormality (stenosis or occlusion), severity of arterial abnormality using relevant scales (IST-3 angiography score, Thrombolysis in Cerebral Infarction (TICI) score, Clot Burden Score), collateral supply and visibility of a perfusion defect on CTA source images (CTA-SI). Intra-obse...
Reported risks of hemorrhage from intracranial developmental venous anomalies (DVAs) vary, so we investigated this in a systematic review and population-based study. We systematically reviewed the literature (Ovid Medline and Embase to... more
Reported risks of hemorrhage from intracranial developmental venous anomalies (DVAs) vary, so we investigated this in a systematic review and population-based study. We systematically reviewed the literature (Ovid Medline and Embase to November 7, 2007) and selected studies of >or=20 participants with >or=1 DVA(s) that described their clinical presentation and/or their clinical course over a specified follow-up period. We also identified every adult first diagnosed with a DVA in Scotland from 1999 to 2003 and followed them in a prospective, population-based study. Of 2068 articles detected by the literature search, 15 met our inclusion criteria and described clinical presentation, 8 of which also described the clinical course of DVAs. In the 15 studies of 714 people first presenting with a DVA, 61% were incidental findings, the mode of presentation was unclear in 23%, 6% presented with nonhemorrhagic focal neurological deficit, 6% had caused symptomatic hemorrhage, 4% were ass...
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ABSTRACT The authors report two patients with aneurysmal subarachnoid hemorrhage in whom carotid arteriography revealed aneurysms that had developed at previously normal locations and from infundibula during the years since initial... more
ABSTRACT The authors report two patients with aneurysmal subarachnoid hemorrhage in whom carotid arteriography revealed aneurysms that had developed at previously normal locations and from infundibula during the years since initial angiography. Neither of these patients had congenital anomalies of the cerebral circulation and, apart from smoking in excess of 30 cigarettes a day, there were no common clinical features. The role of congenital and environmental factors in the formation of aneurysms and the enlargement of infundibula are reviewed.
Magnetic resonance angiography (MRA) for determining the degree of carotid stenosis prior to carotid endarterectomy is attractive because it does not have the high morbidity associated with conventional intra-arterial angiography. We... more
Magnetic resonance angiography (MRA) for determining the degree of carotid stenosis prior to carotid endarterectomy is attractive because it does not have the high morbidity associated with conventional intra-arterial angiography. We assessed the interobserver variability in the estimation of the degree of stenosis amongst observers of different experience. In a prospective study, consecutive patients with transient ischaemic attacks and symptomatic tight carotid stenosis shown by Doppler ultrasound underwent conventional intra-arterial angiography and 2-D and 3-D time-of-flight MRA of the carotid bifurcations. The films of the processed MRA images were reviewed blind to other clinical and imaging data by eight observers of different levels of experience and coded for the presence and degree of stenosis. The stenosis on intra-arterial angiography was used as the reference standard. There was considerable variability between observers for estimation of the degree of stenosis on MRA. The observers' accuracy ranged from 41% (student) to 79% (experienced). From these estimations, excluding those of the student, it could be seen that up to 23% of patients who would have had an endarterectomy based on MRA should not have done so according to angiography, and up to 33% of patients who should have had an endarterectomy according to angiography would have inappropriately missed having an endarterectomy based on MRA results. Observer reliability of MRA processed images is not good, even in experienced hands. Using the source images and views of the circle of Willis might improve the accuracy, but a further study is required to assess this.
Status epilepticus is usually a straightforward diagnosis when a patient has two or more seizures without regaining consciousness. However, when status is non-convulsive and, in particular, has a temporal lobe flavour the clinical... more
Status epilepticus is usually a straightforward diagnosis when a patient has two or more seizures without regaining consciousness. However, when status is non-convulsive and, in particular, has a temporal lobe flavour the clinical presentation may be misleading. Presentation with automatic or psychic behaviour is well recorded. We report a patient with nonconvulsive status who presented with progressive dysphasia with widespread CT and MRI changes. The dysphasia and imaging changes led to a diagnosis of a probable neoplastic brain process but reversed with anticonvulsant treatment.
Coated coils for endovascular treatment of cerebral aneurysm were developed to reduce recurrence and retreatment rates, and have been in clinical use for 8-9 years without robust evidence to determine their efficacy. We assessed the... more
Coated coils for endovascular treatment of cerebral aneurysm were developed to reduce recurrence and retreatment rates, and have been in clinical use for 8-9 years without robust evidence to determine their efficacy. We assessed the efficacy and safety of hydrogel-coated coils. This randomised trial was undertaken in 24 centres in seven countries. Patients aged 18-75 years with a previously untreated ruptured or unruptured cerebral aneurysm of 2-25 mm in maximum diameter were randomly allocated (1:1) to aneurysm coiling with either hydrogel-coated coils or standard bare platinum coils (control). Randomisation was done with a computer-generated sequence, stratified by aneurysm size, shape, and dome-to-neck ratio; intention to use assist device; and by region. Participants and those assessing outcomes were masked to allocation. Analysis was by modified intention to treat (excluding missing data). Primary outcome was a composite of angiographic and clinical outcomes at 18-month follow-up. We also did prespecified subgroup analyses of characteristics likely to be relevant to angiographic outcome. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN30531382. 249 patients were allocated to the hydrogel coil group and 250 to the control group. In 44 of 467 patients for whom an 18-month composite primary outcome was unavailable, 6-month angiographic results were used. 70 (28%) patients in the hydrogel group and 90 (36%) control patients had an adverse composite primary outcome, giving an absolute reduction in the proportion of adverse composite primary outcomes with hydrogel of 7·0% (95% CI -1·6 to 15·5), odds ratio (OR) 0·73 (0·49-1·1, p=0·13). In a prespecified subgroup analysis in recently ruptured aneurysms, there were more adverse composite primary outcomes in the control group than in the hydrogel group-OR 2·08 (1·24-3·46, p=0·014). There were 8·6% fewer major angiographic recurrences in patients allocated to hydrogel coils-OR 0·7 (0·4-1·0, p=0·049). There were five cases of unexplained hydrocephalus in not-recently-ruptured aneurysms in the hydrogel coil group and one case in the control group. Whether use of hydrogel coils reduces late aneurysm rupture or improves long-term clinical outcome is not clear, but our results indicate that their use lowers major recurrence. MicroVention Inc.
BACKGROUND Aneurysmal subarachnoid haemorrhage (SAH) is devastating for many young and middle aged patients. Mortality and disability have altered little over the past 20 years (Hopet al. 1997). Moreover, about one-quarter of patients do... more
BACKGROUND Aneurysmal subarachnoid haemorrhage (SAH) is devastating for many young and middle aged patients. Mortality and disability have altered little over the past 20 years (Hopet al. 1997). Moreover, about one-quarter of patients do not even survive long enough to reach hospital. Of those that do, about one-third rebleed in the first three weeks with a subsequent mortality of 60–80% (Alvord et al. 1972; Kassell et al. 1990; Brilstra et al. 2000; Roos et al. 2000). The first concern after resuscitation is therefore to secure the aneurysm, and so prevent rebleeding. This also allows more aggressive treatment of the complications of SAH such as vasospasm. Since Dandy first surgically clipped an aneurysm in the 1930s, clipping has until recently been the accepted method of isolating the aneurysm from the parent artery. Although clipping was never subjected to a randomised trial, it has been calculated that it reduces the mortality
A double blind, placebo controlled, escalating dose study was undertaken in five healthy, conscious volunteers to investigate the effects of human synthetic alpha calcitonin gene-related peptide (CGRP) on middle cerebral artery (MCA)... more
A double blind, placebo controlled, escalating dose study was undertaken in five healthy, conscious volunteers to investigate the effects of human synthetic alpha calcitonin gene-related peptide (CGRP) on middle cerebral artery (MCA) blood flow velocity using transcranial Doppler sonography. During placebo infusion, there was no significant change in any of the parameters studied. During CGRP infusion, all subjects showed flushing of the face and neck. Infusion of CGRP caused a significant increase in arterial pulse pressure and heart rate and a fall in diastolic and mean arterial blood pressure when compared to baseline. Peak and mean MCA velocity did not change significantly. There was a significant increase in pulsatility index though interpretation of this was confounded by the central systemic effects of CGRP. The observed haemodynamic changes may be explained by a prompt sympathetic nervous system response in order to maintain mean arterial blood pressure. Our data suggest that if cerebral vasodilatation had occurred, it was not associated with increased blood flow as an increase in MCA velocity might have been expected. An alternative explanation is that, at the doses employed, CGRP did not cause dilatation of normal cerebral vessels in healthy subjects. This does not however exclude the fact that CGRP may cause dilatation of a spastic artery as seen in cerebral vasospasm following subarachnoid haemorrhage.
Simple methods of quantifying selected physical characteristics of angiographic catheters, which are likely to influence their in vivo performance, have been developed. The torsional stiffness ('torque') of catheters was... more
Simple methods of quantifying selected physical characteristics of angiographic catheters, which are likely to influence their in vivo performance, have been developed. The torsional stiffness ('torque') of catheters was measured, and tip control ('manoeuvrability') in an angiographic phantom was studied. Both braided and unbraided catheters were investigated all having the 'headhunter' tip shape. Significant differences between measurements made at 20 and 37 degrees C were found. Torsional stiffness was not a good predictor of performance in the angiographic phantom. Ethylene oxide re-sterilization has only a limited effect on the physical characteristics studied.
A 64-year-old man with right aural discharge presented complaining of progressive deafness. Other otological symptoms were absent and specifically there was no seventh nerve paresis. A right aural polyp was identified and biopsied.... more
A 64-year-old man with right aural discharge presented complaining of progressive deafness. Other otological symptoms were absent and specifically there was no seventh nerve paresis. A right aural polyp was identified and biopsied. Histology showed the polyp to be a schwannoma.Subsequent temporal bone computed tomography showed expansion of the distal facial canal. At operation, the schwannoma filled the middle ear cleft and extended from the genu to the region of the stylomastoid foramen. The floor of the middle ear had been eroded, exposing the jugular bulb.Facial paresis is the usual presenting feature of a facial schwannoma, while deafness, ageusia and reduced lacrimation are variable, dependent upon the site of the lesion. The absence of facial palsy as a presenting feature is very rare and this case illustrates the need for histological examination of all abnormal aural material.
Abstract
Amongst in vivo skin imaging methods, magnetic resonance (MR) imaging and spectroscopy is of high interest not only for its ability to distinguish structures at a submillimetre scale but also for its ability to describe the physiology of... more
Amongst in vivo skin imaging methods, magnetic resonance (MR) imaging and spectroscopy is of high interest not only for its ability to distinguish structures at a submillimetre scale but also for its ability to describe the physiology of the different skin layers through the measurement of their intrinsic MR parameters. High spatial resolution MR imaging allows the differentiation of epidermis, dermis and hypodermis. Cutaneous appendages such as hair follicles are also clearly visible. By measuring proton relaxation times and proton density, it is possible to go a step further in the description of skin physiology in vivo through the analysis of water-macromolecular interactions within the dermis as an example. Finally, quantification of water and lipid components in healthy and diseased adipose tissue by localized spectroscopy is also described. Even if MR imaging is of little interest for dermatological diagnosis, some preliminary studies have shown interesting results for preoperative staging, postoperative follow-up, and assessment of the efficacy of new dermatological products. In healthy skin, MR imaging and spectroscopy is a very promising method for the study of chronological and photoageing effects.
Alteplase, an intravenously administered form of recombinant tissue plasminogen activator (rt-PA), remains the only US FDA-approved thrombolytic treatment for acute ischemic stroke within 3 h of symptom onset. Patients treated with... more
Alteplase, an intravenously administered form of recombinant tissue plasminogen activator (rt-PA), remains the only US FDA-approved thrombolytic treatment for acute ischemic stroke within 3 h of symptom onset. Patients treated with intravenous rt-PA are at least 30% more likely to have minimal or no disability at 3 months compared with placebo. Despite an increased risk of symptomatic intracranial hemorrhage, rt-PA does not increase mortality. The benefit achieved with rt-PA is cost effective and sustained 1 year after treatment. Despite its clear benefit, rt-PA remains underutilized. Although the future of acute ischemic stroke treatment will most likely involve a multi-faceted treatment approach, the primary objective remains to establish recanalization of the involved vessel. For patients with acute ischemic stroke within the first 3 h of symptom onset, rt-PA remains the first step in accomplishing this goal.
OBJECTIVE Previous studies of a cohort of 100 patients with IDDM have shown that a history of recurrent severe hypoglycemia is associated with a modest impairment of cognitive function. The aim of the present study was to determine... more
OBJECTIVE Previous studies of a cohort of 100 patients with IDDM have shown that a history of recurrent severe hypoglycemia is associated with a modest impairment of cognitive function. The aim of the present study was to determine whether IDDM patients with and without a history of severe hypoglycemia have lesions in the brain that are identifiable by magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) and to investigate the putative relationship of any structural brain abnormalities with cognitive function. RESEARCH DESIGN AND METHODS MRI and MRS of the brain were performed in 22 patients from the original cohort. Eleven IDDM patients with no history of severe hypoglycemia (group A) were compared with 11 IDDM patients who had a history of five or more episodes of severe hypoglycemia (group B). RESULTS Nine patients (41%) had abnormal scans. Two types of abnormalities were observed: high-intensity rounded lesions, > 3 mm in diameters, distributed in the pe...
ABSTRACT

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