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Cerebral small vessel disease (SVD) causes lacunar stroke and vascular cognitive impairment in older people. The pathogenic pathways from vessel pathology to parenchymal damage in SVD are unknown. Neurofilaments are axonal structural proteins. Neurofilament-light (NfL) is an emerging biomarker for neurological disease. Here, we examined the high molecular weight form neurofilament-heavy (NfH) and quantified a characteristic pattern of peri-arterial (vasculocentric) NfH labeling. Subcortical frontal and parietal white matter from young adult controls, aged controls, and older people with SVD or severe Alzheimer disease (n = 52) was immunohistochemically labeled for hyperphosphorylated NfH (pNfH). The extent of pNfH immunolabeling and the degree of vasculocentric axonal pNfH were quantified. Axonal pNfH immunolabeling was sparse in young adults but a common finding in older persons (controls, SVD, or AD). Axonal pNfH was often markedly concentrated around small penetrating arteries. This vasculocentric feature was more common in older people with SVD than in those with severe AD (p = 0.004). We conclude that axonal pNfH is a feature of subcortical white matter in aged brains. Vasculocentric axonal pNfH is a novel parenchymal lesion that is co-located with SVD arteriopathy and could be a consequence of vessel pathology.

Cerebral small vessel disease (SVD) is common in older people and is associated with lacunar stroke, white matter hyperintensities (WMH) and vascular cognitive impairment. Cerebral blood flow (CBF) is reduced in SVD, particularly within white matter.Here we quantified test–retest reliability in CBF measurements using pseudo-continuous arterial spin labelling (pCASL) in older adults with clinical and radiological evidence of SVD (N=54, mean (SD): 66.9 (8.7) years, 15 females/39 males). We generated whole-brain CBF maps on two visits at least 7 days apart (mean (SD): 20 (19), range 7-117 days).Test–retest reliability for CBF was high in all tissue types, with intra-class correlation coefficient [95%CI]: 0.758 [0.616, 0.852] for whole brain, 0.842 [0.743, 0.905] for total grey matter, 0.771 [0.636, 0.861] for deep grey matter (caudate-putamen and thalamus), 0.872 [0.790, 0.923] for normal-appearing white matter (NAWM) and 0.780 [0.650, 0.866] for WMH (all pWe conclude that pCASL has high test–retest reliability as a quantitative measure of CBF in older adults with SVD. These findings support the use of pCASL in routine clinical imaging and as a clinical trial endpoint.All data come from the PASTIS trial, prospectively registered at: https://eudract.ema.europa.eu (2015-001235-20, registered 13/05/2015), http://www.clinicaltrials.gov (NCT02450253, registered 21/05/2015).

Strokectomy means surgical excision of infarcted brain tissue post-stroke with preservation of skull integrity, distinguishing it from decompressive hemicraniectomy. Both can mitigate malignant middle cerebral artery (MCA) syndrome but evidence regarding strokectomy is sparse. Here, we report our data and meta-analysis of strokectomy compared to hemicraniectomy for malignant MCA infarction. All malignant MCA stroke cases requiring surgical intervention in a large tertiary centre (January 2012–December 2017,N = 24) were analysed for craniotomy diameter, complications, length of follow-up and outcome measured using the modified Rankin score (mRS). Good outcome was defined as mRS 0–3 at 12 months. In a meta-analysis, outcome from strokectomy (pooled from our cohort and published strokectomy studies) was compared with hemicraniectomy (our cohort pooled with published DECIMAL, DESTINY and HAMLET clinical trial data). In our series (N = 24, 12/12 F/M; mean age: 45.83 ± 8.91, range 29–63 years), 4 patients underwent strokectomy (SC) and 20 hemicraniectomy (HC). Among SC patients, craniotomy diameter was smaller, relative to HC patients (86 ± 13.10 mm, 120 ± 4.10 mm, respectively;p = 0.003), complications were less common (25%, 55%) and poor outcomes were less common (25%, 70%). In the pooled data (N = 41 SC, 71 HC), strokectomy tended towards good outcome more than hemicraniectomy (OR 2.2, 95% CI 0.99–4.7;p = 0.051). In conclusion, strokectomy may be non-inferior, lower risk and cost saving relative to hemicraniectomy sufficiently to be worthy of further investigation and maybe a randomised trial.

Background and aim Neutrophil-lymphocyte ratio (NLR) and lymphocyte-monocyte ratio (LMR) are associated with clinical outcomes in malignancy, cardiovascular disease and stroke. Here we investigate their association with outcome after acute ischaemic stroke treated by mechanical thrombectomy (MT). Methods Patients were selected using audit data for MT for acute anterior circulation ischaemic stroke at a UK centre from May 2016–July 2017. Clinical and laboratory data including neutrophil, lymphocyte and monocyte count tested before and 24 h after MT were collected. Poor functional outcome was defined as modified Rankin Scale (mRS) of 3–6 at 3 months. Multivariable logistic regression analyses were performed to explore the relationship of NLR and LMR with functional outcome. Results One hundred twenty-one patients (mean age 66.4 ± 16.7, 52% female) were included. Higher NLR (adjusted OR 0.022, 95% CI, 0.009–0.34, p = 0.001) and lower LMR (adjusted OR − 0.093, 95% CI (− 0.175)−(− 0.012), p = 0.025) at 24-h post-MT were significantly associated with poorer functional outcome when controlling for age, baseline NIHSS score, infarct size, presence of good collateral supply, recanalisation and symptomatic intracranial haemorrhage on multivariate logistic regression. Admission NLR or LMR were not significant predictors of mRS at 3 months. The optimal cut-off values of NLR and LMR at 24-h post-MT that best discriminated poor outcome were 5.5 (80% sensitivity and 60% specificity) and 2.0 (80% sensitivity and 50% specificity), respectively on receiver operating characteristic curve analysis. Conclusion NLR and LMR tested at 24 h after ictus or intervention may predict 3-month functional outcome.

The COVID-19 pandemic has resulted in periods of remote working for some junior doctors, due to shielding and clinical vulnerability. This report offers practical guidance for junior doctors and their supervisors on how to make a period of remote working safe and effective, while maintaining education, training progression and morale. We outline specific challenges and practicalities that should be considered prior to commencing remote working and discuss what tasks and activities are best suited to a remote-working junior doctor. We offer a positive outlook that, with adequate support, a junior doctor can continue to progress in their training while working remotely, and can make a period of remote working an opportunity for personal and professional development while remaining an effective and valuable member of the clinical team.

Introduction\ud There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI.\ud \ud Methods\ud In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling.\ud \ud Results\ud Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (–7.8, –4.9 mmHg; P < .001). No serious adverse events were observed.\ud \ud Discussion\ud This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.

There is no consensus on how to structure and deliver neurology training. The General Medical Council’s annual National Training Survey indicates that the quality of UK neurology training is very variable, but does not explain this variation. We used the survey data to identify the four highest and lowest performing sites for neurology training across the UK. We conducted semistructured interviews with groups of local trainees and, separately, local trainers in an exploratory qualitative study, and identified common themes across a range of aspects of neurology training. Here we present our findings, share case studies from top-performing sites and make recommendations on how best to train a neurologist.

Background and Purpose: Spontaneous intracerebral hemorrhage (sICH) is a common form of hemorrhagic stroke, with high mortality and morbidity. Pathophysiological mechanisms in sICH are poorly understood and treatments limited. Neuroinflammation driven by microglial-macrophage activation contributes to brain damage post-sICH. We aim to test the hypothesis that an anti-inflammatory (repair) process occurs in parallel with neuroinflammation in clinical sICH. Methods: We performed quantitative analysis of immunohistochemical markers for microglia and macrophages (Iba1, CD68, TMEM119, CD163, and CD206) in brain tissue biospecimens 1 to 12 days post-sICH and matched control cases. In a parallel, prospective group of patients, we assayed circulating inflammatory markers (CRP [C-reactive protein], total white cell, and monocyte count) over 1 to 12 days following sICH. Results: In 27 supratentorial sICH cases (n=27, median [interquartile range] age: 59 [52–80.5], 14F/13M) all microglia-macrophage markers increased post-sICH, relative to control brains. Anti-inflammatory markers (CD163 and CD206) were elevated alongside proinflammatory markers (CD68 and TMEM119). CD163 increased progressively post-sICH (15.0-fold increase at 7–12 days, P P P =0.020) then declined at 7 to 12 days. Monocytes increased from 0 to 2 to 3 to 5 days (1.8-fold, P Conclusions: An anti-inflammatory pathway, enlisting native microglia and blood monocytes, occurs alongside neuroinflammation post-sICH. This novel pathway offers therapeutic targets and a window of opportunity (3–5 days post-sICH) for delivery of therapeutics via invading monocytes.

Intravenous thrombolysis with alteplase within 4.5 hours from symptom onset is a well-established treatment of acute ischaemic stroke (AIS). The aim was to compare alteplase for AIS between patients aged >80 and ≤80 years in our registry data, from 2013 to 2018. Mechanical thrombectomy cases were excluded. We assessed clinical outcomes over the six-year period and between patients aged over 80 and ≤80 years, using measures including the discharge modified Rankin Scale (mRS), 24-hour National Institutes of Health Stroke Scale (NIHSS) improvement, and symptomatic intracerebral haemorrhage (sICH) rate. Of a total of 805 AIS patients who received intravenous alteplase, 278 (34.5%) were over 80 years old, and 527 (65%) were younger. 616 (76.5%) received thrombolysis ≤ 3 hours after symptom onset and 189 (23.5%) within 3-4.5 hours. Median baseline mRS and NIHSS of the elderly cohort were 1 (IQR 0-5) and 13 (IQR 2-37), respectively, compared to the younger cohort 0 (IQR 0-5) and 9 (IQR 0-29). The sICH rate was 7.2% in the elderly and 4.6% in those ≤80 years, p = 0.05 . NIHSS improved within 24 hours in 34% of the elderly cohort compared to 35% in the younger cohort. At hospital discharge, the mortality rate was 9% in the elderly cohort compared to the 6% in the younger cohort, p = 0.154 . 25% of patients aged >80 years had mRS ≤ 2 compared to 47% in the younger patients ( p < 0.0001 ). In conclusion, thrombolysis in elderly patients results in clinical improvement comparable to younger patients.

Introduction\ud Radiolabeled ligands for fibrillar amyloid beta (Aβ) peptides are used in positron emission tomography (PET) for dementia diagnosis. Current ligands do not discriminate parenchymal amyloid plaques from cerebral amyloid angiopathy (CAA).\ud \ud Methods\ud We undertook neuropathological examination of 65 older people (81.6 ± 7.96 (mean ± SD) years, 27F/38M): 15 with neuropathological diagnosis of AD, 25 with neuropathological diagnosis of other neurodegenerative dementias (Lewy body dementia and Parkinson disease dementia), and 25 without significant neurodegenerative pathology.\ud \ud Results\ud We observed CAA in non‐Alzheimer's dementia (non‐AD dementia) and control brains, of comparable extent to those with neuropathologically confirmed AD. Aβ‐positive vessel density did not differ significantly between non‐AD dementia and control groups. Across all subjects there was a highly significant correlation between vessel Aβ40 density and vessel Aβ42 density (Spearman rho = 0.855, P < .001). CAA was absent or sparse in subcortical white matter across all patient groups.\ud \ud Conclusion\ud Our data indicate that CAA can be abundant in non‐AD brains and raise a cautionary note regarding interpretation of amyloid PET imaging.

Cerebral small vessel disease in deep penetrating arteries is a major cause of lacunar infarcts, white matter lesions and vascular cognitive impairment. Local cerebral blood flow in these small vessels is controlled by endothelial-derived nitric oxide, which exerts a primary vasodilator stimulus on vascular myocytes, via cytoplasmic cyclic GMP. Here, we investigated whether the cGMP-degrading enzyme phosphodiesterase-5 (PDE5) is present in small penetrating arteries in the deep subcortical white matter of older people. Frontal cortical tissue blocks were examined from donated brains of older people (n = 42, 24 male: 18 female, median age 81, range: 59-100 years). PDE5, detected by immunohistochemical labeling, was graded as absent, sparse, or abundant in vascular cells within small arteries in subcortical white matter (vessel outer diameter: 20-100 µm). PDE5 labeling within arterial myocytes was detected in all cases. Degree of PDE5 expression (absent, sparse, or abundant) was not associated with age or with neuropathological diagnosis of small vessel disease. In conclusion, PDE5 is present in vascular myocytes within small penetrating arteries in older people. This is a potential molecular target for pharmacological interventions.

Background Cerebral small vessel disease is a common cause of vascular cognitive impairment in older people, with no licensed treatment. Cerebral blood flow is reduced in small vessel disease. Tadalafil is a widely prescribed phosphodiesterase-5 inhibitor that increases blood flow in other vascular territories. The aim of this trial is to test the hypothesis that tadalafil increases cerebral blood flow in older people with small vessel disease. Methods/design Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS) is a phase II randomised double-blind crossover trial. In two visits, 7-30 days apart, participants undergo arterial spin labelling to measure cerebral blood flow and a battery of cognitive tests, pre- and post-dosing with oral tadalafil (20 mg) or placebo. Sample size: 54 participants are required to detect a 15% increase in cerebral blood flow in subcortical white matter (p

Recombinant tissue plasminogen activator (rtPA) is currently the only approved thrombolytic agent for treating acute ischaemic stroke that is widely used in clinical practice. However, it may cause haemorrhage and hypersensitivity reactions. Orolingual angioedema is an infrequent, usually mild but potentially life threatening, hypersensitivity reaction to rtPA. Our understanding of the basic biology of angioedema has increased in recent years. There is growing evidence that rtPA-induced orolingual angioedema is driven mainly by bradykinin generation rather than it being an anaphylactic response. Monitoring is important because orolingual angioedema may evolve and compromise airways and a small number do have angioedema as part of systemic anaphylaxis. There are no published guidelines for treating rtPA-induced orolingual angioedema, although some evidence suggests that those refractory to standard antianaphylactic agents may resolve with bradykinin B2 receptor antagonists. It is important that responses to orolingual angioedema are proportionate and that patients are closely monitored.

Objectives\ud To assess the prevalence of high on-clopidogrel platelet reactivity (HCPR) in patients with ischaemic stroke or transient ischaemic attack (IS/TIA), their outcome and genetic basis of on-treatment response variability in IS/TIA patients.\ud \ud Methods\ud We conducted a comprehensive search of PubMed and EMBASE from their inceptions to March 9, 2019. Studies that reported absolute numbers/percentages of HCRP at any time point after IS/TIA onset evaluated with any type of platelet function tests, clinical outcomes and genotyping data were included.\ud \ud Results\ud Among 21 studies of 4312 IS/TIA patients treated with clopidogrel, the pooled prevalence of HCPR was 28% (95%CI: 24–32%; high heterogeneity: I2 = 88.2%, p < 0.001). Heterogeneity degree diminished across groups defined by the HCPR testing method. Clopidogrel non-responder IS/TIA patients had poorer outcome compared to responders (RR = 2.09, 95%CI: 1.61–2.70; p = 0.036; low heterogeneity across studies: I2 = 27.4%, p = 0.210). IS/TIA carriers of CYP2C19*2 or CYP2C19*3 loss of function alleles had a higher risk of HCPR compared to wild type (RR = 1.69, 95%CI: 1.47–1.95; p < 0.001; I2 = 0.01%, p = 0.475).\ud \ud Conclusions\ud This systematic review shows a high prevalence of clopidogrel resistance in IS/TIA and poor outcome in these patients. CYP2C19 polymorphisms may potentially influence clopidogrel resistance.

St George's Hospital hyperacute neurology service (HANS) is a comprehensive, consultant-delivered service set in a teaching hospital regional neuroscience centre. The service addresses deficiencies in acute neurological care previously highlighted by the Royal College of Physicians and the Association of British Neurologists. HANS adopts a disease-agnostic approach to acute neurology, prioritising the emergency department (ED) management of both stroke and stroke mimics alike alongside proactive daily support to the acute medical unit and acute medical take. Rapid access clinics provide a means to assess ambulatory patients, providing an outlet to reduce the burden of referral from primary care to acute medicine. This paper reports the results from the first year of the service. Admission was avoided in 25% of the cases reviewed in the ED. Compared to historic data, there was a significant improvement in the length of stay for non-stroke disorders while the occupancy of stroke beds by non-stroke cases reduced by 50%. The configuration of this service is replicable in other neuroscience centres and provides a framework to reduce the barriers facing patients who present with acute neurological symptoms.

Nitrones (e.g. α-phenyl-N-tert-butyl nitrone; PBN) are cerebroprotective in experimental stroke. Free radical trapping is their proposed mechanism. As PBN has low radical trapping potency, we tested Sgk1 induction as another possible mechanism. PBN was injected (100 mg/kg, i.p.) into adult male rats and mice. Sgk1 was quantified in cerebral tissue by microarray, quantitative RT-PCR and western analyses. Sgk1+/+ and Sgk1−/− mice were randomized to receive PBN or saline immediately following transient (60 min) occlusion of the middle cerebral artery. Neurological deficit was measured at 24 h and 48 h and infarct volume at 48 h post-occlusion. Following systemic PBN administration, rapid induction of Sgk1 was detected by microarray (at 4 h) and confirmed by RT-PCR and phosphorylation of the Sgk1-specific substrate NDRG1 (at 6 h). PBN-treated Sgk1+/+ mice had lower neurological deficit ( p +/+ mice. PBN-treated Sgk1−/− mice did not differ from saline-treated Sgk1−/− mice. Saline-treated Sgk1−/− and Sgk1+/+ mice did not differ. Brain Sgk3:Sgk1 mRNA ratio was 1.0:10.6 in Sgk1+/+ mice. Sgk3 was not augmented in Sgk1−/− mice. We conclude that acute systemic treatment with PBN induces Sgk1 in brain tissue. Sgk1 may play a part in PBN-dependent actions in acute brain ischemia.

Acute neurological problems are common, accounting for 10–20% of medical admissions. In the coming years, there will be increased neurology involvement in the acute care of these patients complementing traditional outpatient-based services. Models of acute neurology are reliant on close collaboration between the emergency department, acute medicine and neurology and should integrate with existing hyperacute stroke pathways. In this article the authors briefly describe the two models of acute neurology set up recently in our neuroscience group and suggest a clinical approach that may help non-neurologists involved in acute care settings. The authors emphasise some of the lessons learnt in delivering the service, particularly the importance of focusing on the acute problem and tailoring the examination and investigations to tackling it in the context of the patient9s functional level and personal circumstances. Early neurology intervention can reduce admission and hospital length of stay.

Vijyarangam Senthilkumar Shanmugam (“Kumar”) was an incredible, brave, and sincere doctor. He completed his medical training in 2000, graduating from Madurai Medical College in India. On the eve of his final practical MBBS examination, he was riding his “bullet” motorbike to pay a visit to the temple in Madurai. On the way, he was forced to swerve to avoid some boys playing a ball game, one of whom ran out into the road. He crashed, breaking his forearm. He abandoned the motorbike and returned to his digs, where he attempted to reset his arm by himself. Eventually, his friends persuaded him …

Stroke services have been centralised in several countries in recent years. Diagnosing acute stroke is challenging and a high proportion of patients admitted to stroke units are diagnosed as a non-stroke condition (stroke mimics). This study aims to describe the stroke mimic patient group, including their impact on stroke services. We analysed routine clinical data from 2,305 consecutive admissions to a stroke unit at St George's Hospital, London. Mimic groupings were derived from 335 individual codes into 17 groupings. From 2,305 admissions, 555 stroke mimic diagnoses were identified (24.2%) and 72% of stroke mimics had at least one stroke risk factor. Common mimic diagnoses were headache, seizure and syncope. Medically unexplained symptoms and decompensation of underlying conditions were also common. Median length of stay was 1 day; a diagnosis of dementia (p=0.028) or needing MRI (p=0.006) was associated with a longer stay. Despite emergency department assessment by specialist clinicians and computed tomography brain, one in four suspected stroke patients admitted to hospital had a non-stroke diagnosis. Stroke mimics represent a heterogeneous patient group with significant impacts on stroke services. Co-location of stroke and acute neurology services may offer advantages where service reorganisation is being considered.

Summary Objectives Audits in the United Kingdom and other countries show that only a small proportion of eligible stroke patients receive thrombolysis. Providing 24-hour thrombolysis cover presents major challenges in both infrastructure and staffing. One model for improving access is to provide out-of-hours cover in a regional centre but this may present problems including greater delays to hospital admissions. Design Evaluation of the introduction of a ‘hub-and-spoke’ model of thrombolysis to increase access to thrombolysis for patients in south west London. One-year data are presented. Setting A network in south-west London comprised of a hub hospital and three district ‘spoke’ hospitals. Participants All suspected stroke admissions to a regional stroke centre. Main outcome measures Thrombolysis rates for acute stroke. Results Increased out-of-hours thrombolysis rates were achieved with only a small increase in stroke admissions (approximately 10%) in the hub hospital. Thrombolysis rates increased from 1.2 per 100 stroke admissions for the local daytime service to 6 per 100 admissions for the regional service. Most patients thrombolysed were not local to the hub hospital. Only 1 in 4 patients considered for thrombolysis was thrombolysed, in line with previous data. Ten percent of all thrombolysis calls were not stroke but represented stroke mimics. Median length of stay was 6 days (target was 3 days). Fifty percent of the thrombolysed patients from spoke hospitals were discharged directly home. Conclusions In an urban area, a hub-and-spoke thrombolysis model increased access to thrombolysis without resulting in a marked increase in overall stroke admission numbers for the hub hospital. Proactive plans to repatriate patients back to district hospitals are required, and repatriation protocols have to prioritize regional patients over other targets in spoke hospitals to facilitate capacity in the hub hospital.

Patients who are face, arm, speech test (FAST) positive may have a stroke mimic diagnosis. Careful attention to the speed of onset of symptoms is paramount. Magnetic resonance imaging is helpful in supplementing the clinical assessment.

Background and Purpose— Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS) patients with carotid stenosis were randomized between endovascular treatment and endarterectomy. The rates of residual severe stenosis and restenosis and their contribution to recurrent symptoms was unclear. Methods— Endovascular patients were treated by balloon angioplasty alone (88%) or stenting (22%). Patches were used in 63% of endarterectomy patients. Carotid stenosis was categorized as mild (0% to 49%), moderate (50% to 69%), severe (70% to 99%), or occluded, using standardized Doppler ultrasound criteria at the examination closest to 1 month (n=283) and 1 year (n=347) after treatment. Recurrent cerebrovascular symptoms during follow-up were analyzed. Results— More patients had ≥70% stenosis of the ipsilateral carotid artery 1 year after endovascular treatment than after endarterectomy (18.5% versus 5.2%, P =0.0001). Residual severe stenosis was present in 6.5% of patients at 1 month after endovascular treatment. Between 1 month and 1 year, restenosis to ≥70% stenosis occurred in 10.5% of the endovascular group. After endarterectomy, 1.7% had residual severe stenosis at 1 month, and 2.5% developed severe restenosis. The results were significantly better after stenting compared with angioplasty alone at 1 month ( P P =0.02), but most were transient ischemic attacks and none were disabling or fatal strokes. There were no recurrent symptoms in the 9 endarterectomy patients with ≥70% stenosis at 1 year. Conclusions— Carotid stenosis 1 year after endovascular treatment is partly explained by poor initial anatomical results and partly by restenosis. The majority of patients were treated by angioplasty without stenting. Further randomized studies are required to determine whether newer carotid stenting techniques are associated with a lower risk of restenosis. The low rate of recurrent stroke in both endovascular and endarterectomy patients suggests that treatment of restenosis should be limited to patients with recurrent symptoms, but long term follow up data are required.

The primary deficit in acute ischaemic stroke is one of impaired blood flow. Part of the cerebral circulation is occluded either by in situ thrombosis, or embolism from the heart or a more proximal artery (for example, the ipsilateral internal carotid artery). Angiographic studies of the cerebral circulation in acute stroke demonstrate occluding thrombus in up to 80% of patients.1 The aim of thrombolytic therapy therefore is to lyse an occluding thrombus or embolus and reduce the volume of cerebral tissue irreversibly damaged. Such an approach is of course successfully employed in the treatment of acute myocardial infarction.2 However a major complication of thrombolysis in stroke is cerebral haemorrhage which could offset any beneficial effects. Here we review the available evidence for thrombolysis in acute stroke and suggest imaging methods that could be used to aid future selection of patients who are most likely to benefit from such treatment. Data from animal stroke models confirm that cerebral blood flow can be restored to near normal levels after administration of recombinant tissue plasminogen activator (rtPA)3 and that thrombolysis results in smaller infarcts and improved neurological function.4-6 Comparison of streptokinase with rtPA suggested that, although their effectiveness in producing thrombolysis was comparable, streptokinase was less clot specific and animals treated with it had increased frequency and severity of cerebral haemorrhage.7 Animals treated with rtPA had the same frequency of cerebral haemorrhages as those treated with saline but the proportion of large haematomas was increased.6 In humans, thrombolytic therapy was first tried over 40 years ago but was largely abandoned due to excess mortality from major haemorrhagic complications.8 When computed tomography became widely available interest in the use of thrombolysis returned, leading to several larger randomised controlled trials. A dose escalation study using rtPA reported that …

Acute stroke treatment using aspirin and/or heparin was studied in the International Stroke Trial (IST) and Chinese Acute Stroke Trial (CAST) which randomised over 40,000 patients altogether. Combining the results demonstrated that aspirin (150-300 mg) given within 48 h of the onset of stroke produced a small but significant improvement in outcome (death or dependency) 4 weeks to 6 months after stroke of about 1 patient per 100 treated. There was a significant reduction in recurrent ischaemic stroke of similar degree, which was not associated with significant increase in cerebral haemorrhage. Therefore, aspirin should be used as early secondary prevention against recurrent stroke, after excluding cerebral haemorrhage by scanning the patient. Heparin does not improve clinical outcome after stroke even in patients in atrial fibrillation. It decreased recurrent ischaemic stroke significantly in IST, but at the cost of a significant increase in cerebral haemorrhage. Low molecular weight heparins and heparinoids have not proved any more beneficial. Therefore, heparin does not appear to be a useful routine therapy in acute stroke. The use of heparin should, therefore, be limited to patients at high risk of deep vein thrombosis or early recurrence.

Background and Purpose — 1 H MR spectroscopy can be used to study biochemical changes occurring in the brain in stroke. We used it to examine the relationship between metabolite concentration ( N -acetyl aspartate [NAA], lactate, cholines and creatines), size of infarct, clinical deficit, and 3-month clinical outcome in patients with middle cerebral artery (MCA) territory infarction. Methods —Thirty-one patients with acute MCA territory infarction were recruited within 72 hours of the onset of symptoms. Single-voxel short echo time stimulated echo acquistion mode spectroscopy was used to obtain metabolite data from the infarct core. Metabolite concentrations were determined with use of variable projection time domain-fitting analysis. Infarct size was determined with T2-weighted images. Patient outcome groups at 3 months were “independent,” “dependent,” or “dead.” Results —All patients (100%; 95% CI 75% to 100%) who had an infarct >70 mL did poorly. Eighteen of 20 patients (90%; 95% CI 68% to 99%) with a core NAA concentration 7 mmol/L did well. Combining these results showed that all patients who had an initial infarct volume >70 mL did poorly, irrespective of the NAA concentration. Of those patients with infarcts 7 mmol/L did well (88%; 95% CI 47% to 100%), whereas those with a lower NAA concentration did poorly (80%; 95% CI 44% to 97%). There was no association between other metabolite concentrations and outcome. Conclusions —Infarct volume and NAA concentration can together predict clinical outcome in MCA infarction in humans.

Stroke has become a major NHS priority. Daniel Davies and colleagues look at a career in the area