Joanna Wardlaw

Disappearing hyperdense middle cerebral artery sign in ischaemic stroke patients treated with intravenous thrombolysis: clinical course and prognostic significance.

Background and purpose: Hyperdense middle cerebral artery sign (HMCAS) on CT is a well known indication of thromboembolic arterial occlusion. Its disappearance after thrombolytic therapy is poorly described. Taking the rate of HMCAS disappearance as a surrogate for MCA recanalisation, its prognostic value after intravenous thrombolysis was examined. Methods: 1905 stroke patients with HMCAS on admission CT scan in the Safe Implementation of Treatment in Stroke-International Stroke Thrombolysis Register (SITS-ISTR) were studied. On follow-up CT scans 22–36 h after thrombolysis, HMCAS disappeared in 831 cases, persisted in 788 and was uncertain in 122; follow-up CT was not done in 164 cases. Results: Patients whose HMCAS disappeared were younger (median age 67 years vs 69 years for persistent; pu200a=u200a0.03), with milder stroke (admission National Institute of Health Stroke Scale (NIHSS) score was 16 vs 17; p<0.005) and were less likely to have early infarct signs on admission CT (26% vs 33%; p<0.005). Patients with disappearing HMCAS were more likely to have early improvement in NIHSS score (median improvement 2 vs 0 at 2 h; 4 vs 1 at 24 h), be independent at 3 months (42% vs 19%), with fewer deaths (15% vs 30%) than those with persistent HMCAS. In multivariate analysis, HMCAS disappearance independently predicted functional independence and survival. Early NIHSS improvement independently predicted HMCAS disappearance. Conclusions: HMCAS disappeared after intravenous thrombolysis in about half of cases and these patients had twice as good outcomes compared with those with persistent HMCAS. The prognosis in patients with MCA occlusion that persists after intravenous thrombolysis is poor, which may indicate the need for an alternative treatment approach to this subgroup.

Does Early Reperfusion of a Cerebral Infarct Influence Cerebral Infarct Swelling in the Acute Stage or the Final Clinical Outcome

Forty-seven patients presenting with symptoms of large middle cerebral artery territory infarcts were studied prospectively using serial CT brain scanning to assess infarct extent and swelling, and tr

Sensitivity and Specificity of the Hyperdense Artery Sign for Arterial Obstruction in Acute Ischemic Stroke

Background and Purpose— In acute ischemic stroke, the hyperdense artery sign (HAS) on noncontrast computed tomography (CT) is thought to represent intraluminal thrombus and, therefore, is a surrogate of arterial obstruction. We sought to assess the accuracy of HAS as a marker of arterial obstruction by thrombus. Methods— The Third International Stroke Trial (IST-3) was a randomized controlled trial testing the use of intravenous thrombolysis for acute ischemic stroke in patients who did not clearly meet the prevailing license criteria. Some participating IST-3 centers routinely performed CT or MR angiography at baseline. One reader assessed all relevant scans independently, blinded to all other data; we checked observer reliability. We combined IST-3 data with a systematic review and meta-analysis of all studies that assessed the accuracy of HAS using angiography (any modality). Results— IST-3 had 273 patients with baseline CT or MR angiography and was the largest study of HAS accuracy. The meta-analysis (n=902+273=1175, including IST-3) found sensitivity and specificity of HAS for arterial obstruction on angiography to be 52% and 95%, respectively. HAS was more commonly identified in proximal than distal arteries (47% versus 37%; P=0.015), and its sensitivity increased with thinner CT slices (r=−0.73; P=0.001). Neither extent of obstruction nor time after stroke influenced HAS accuracy. Conclusions— When present in acute ischemic stroke, HAS indicates a high likelihood of arterial obstruction, but its absence indicates only a 50/50 chance of normal arterial patency. Thin-slice CT improves sensitivity of HAS detection. Clinical Trial Registration— URL: http://www.controlled-trials.com/ISRCTN25765518. Unique identifier: ISRCTN25765518.

Differential Associations of Cortical and Subcortical Cerebral Atrophy With Retinal Vascular Signs in Patients With Acute Stroke

Background and Purpose— The relationship of cortical and subcortical cerebral atrophy to cerebral microvascular disease is unclear. We aimed to assess the associations of retinal vascular signs with cortical and subcortical atrophy in patients with acute stroke. Methods— In the Multi-Centre Retinal Stroke Study, 1360 patients with acute stroke admitted to 2 Australian and 1 Singaporean tertiary hospital during 2005 to 2007 underwent neuroimaging and retinal photography. Cortical and subcortical cerebral atrophy were graded based on standard CT scans. A masked assessment of retinal photographs identified focal retinal vascular signs, including retinopathy and retinal arteriolar wall signs (ie, focal arteriolar narrowing, arteriovenous nicking, arteriolar wall light reflex) and measured quantitative signs (retinal arteriolar and venular caliber). Results— After adjusting for age, gender, study site, hypertension, hypercholesterolemia, diabetes, and smoking status, none of the retinal vascular signs assessed were associated with cortical atrophy, whereas retinopathy (OR, 1.9; CI, 1.2 to 3.0) and enhanced arteriolar light reflex (OR, 2.0; CI, 1.2 to 3.2) were significantly associated with subcortical atrophy. Conclusion— Our finding that certain retinal vascular signs are associated with subcortical but not cortical atrophy, suggests a differential pathophysiology between these 2 cerebral atrophy subtypes and a potential role for small vessel disease underlying subcortical cerebral atrophy.

Comparison of a Simple Isotope Method of Predicting Likely Middle Cerebral Artery Occlusion with Transcranial Doppler Ultrasound in Acute Ischaemic Stroke

The accuracy of a simple isotope method of assessing middle cerebral arterial occlusion was compared with that of transcranial Doppler ultrasound and with a careful clinical examination and CT brain scan to predict the probable pattern of cerebral arterial occlusion in 85 acute stroke patients. The isotope method detected likely middle cerebral artery main stem or large branch occlusion with equal accuracy to transcranial Doppler ultrasound. This simple isotope method is a practical way of assessing cerebral arterial occlusion, is inexpensive, non-operator-dependent, faster than transcranial Doppler ultrasound and uses technology which is already widely available. It may be useful for research in acute stroke at present and in future may help guide treatment of acute ischaemic stroke.

Recurrent cerebral haemorrhage in a 65 year old man: advanced clinical neurology course, Edinburgh, 1997.

A 65 year old, right handed, retired police inspector presented to hospital as an emergency. That afternoon, while decorating, he had complained of a headache, although it did not prevent him from continuing with his work. Three hours later, however, his wife found him unable to speak, with a drooped right face and shortly afterwards, complete right sided paralysis. He was known to have hypertension and, 3 months earlier, he had been investigated for weight loss and painless obstructive jaundice. Endoscopic retrograde cholangiopancreatography (ERCP) had shown an impacted gall stone and appearances consistent with a periampullary tumour, although no histology was obtained. Sphincterotomy had led to improvement and the diagnosis had not been pursued further. Routine screening had also disclosed a lymphocytosis of 8.25×109 /l, which was confirmed to be due to an asymptomatic, early chronic lymphocytic leukaemia. His medications consisted of 100 mg atenolol daily, 25 mg mefruside daily, and 400 mg cimetidine twice daily. He smoked 15 cigarettes a day and drank alcohol rarely.nnOn examination, he was drowsy with conjugate deviation of gaze to the left, and had dysphasia, a right homonymous hemianopia, and total right sided paralysis. Fundoscopy was normal. Other than mild jaundice, cardiovascular and general examination was normal. Brain CT (fig 1) showed a large, left frontoparietal haematoma with moderate mass effect and he had a leucocytosis of 21.2×109 (lymphocytes 9.75×109) with a normal haemoglobin and platelet count, and a bilirubin of 28 mmol/l.nnnnFigure 1 nBrain CT (without contrast) on first presentation shows a large left frontoparietal haematoma (white) with some mass effect. Note that the haematoma extends out through the cortex to the surface of the brain.nnnnAfter admission, his wife mentioned that he had been having word finding difficulties for about a year, although it was not clear if this …

Tumors of the Central Nervous System

These volumes in the TUMORS OF THE CENTRAL NERVOUS SYSTEM, will discuss all aspects, including initiation, progression, metastasis and therapy (surgery, radiation and chemotherapy), of the malignancies of the brain and the spinal cord. The most recent information on this project will be presented by 150 experts representing 12 counties. The objective is to discuss all commonly occurring tumors of the central nervous system (CNS).