[Influence of extreme weather conditions on the deployment volume of emergency medical services]. / Einfluss von Wetterextrema auf Einsatzzahlen im Notarztdienst.

BACKGROUND: Due to global warming a worldwide increase in the frequency and intensity of heat waves have been forecast. In the context of the overall increasing number of emergency service calls, weather-induced effects on the number of calls are highly relevant. We evaluated the influence of extreme temperatures on emergency medical services. MATERIALS AND METHODS: The study was conducted in Bochum, Germany. The authors examined the data from 16,767 emergency calls. In addition, the daily updated temperature data were collected for each emergency doctor call. Data were collected from 01 January 2014 until 31 December 2015. The primary question was the influence of extremes of the perceived temperature (PT; on the day of the call and the three previous days) on the diagnosis group of cardiovascular diseases. A secondary question was the influence of extremes of the temperature parameters (air temperature, PT, physiological equivalent temperature [PET]) on the day of call and the three previous days. RESULTS: A total of 16,767 calls were assessed. The threshold values (upper and lower 5%) were -8.7 and 32.5 °C for PT and -0.7 and 26.7 °C for air temperature. Examination of the PT indicated a significantly increased rate of calls for cold spells on the day of the call (RR = 1.14; p = 0.033) as well as a lag effect of 3 days (RR = 1.1; p = 0.049). CONCLUSION: The present study shows that during cold spells there is an increased rate of calls for cardiovascular diseases. This effect is not only observable on the extreme day itself but also 3 days later.

[Nationwide treatment reality of patients with acute ischemic stroke in Germany : Update of the regionalized analysis on use of recanalization treatment procedures and stroke complex treatment]. / Bundesweite Versorgungsrealität von Patienten mit akutem Hirninfarkt in Deutschland : Update der regionalisierten Analyse zur Anwendung rekanalisierender Therapieverfahren und einer Schlaganfallkomplexbehandlung.

BACKGROUND: The guidelines of the German Society for Neurology regarding the diagnostics and treatment of acute ischemic stroke contain the general recommendation of treatment on a stroke unit (SU) and the use of recanalizing treatment (intravenous thrombolysis, IVT; mechanical thrombectomy, MT) in appropriate patients. The nationwide availability of all three components represents a large organizational and healthcare political challenge. OBJECTIVE: Updated nationwide analysis of treatment rates in Germany based on a regionalized evaluation. METHODS: Based on the patient's place of residence, nationwide data of all hospitalized patients were evaluated using the German diagnosis-related groups (DRG) statistics from 2018 and compared with previous years. The rates for SU treatment, IVT and MT in the 412 German regional districts were analyzed. The 412 regions were grouped according to the degree of urbanization. RESULTS: Nationwide, a total of 224,647 patient cases with a main diagnosis of acute ischemic stroke were treated in 1382 hospitals in Germany in 2018. Overall, relatively high treatment rates were determined (SU = 73.3%; IVT = 16.4%; MT = 6.5%). Only 10.2% of treatments in the SU were performed on a SU located at a hospital with no neurology department. The regionalized analysis showed large treatment ranges for all three therapeutic components, with significantly lower treatment rates in regions with a lower degree of urbanization (SU, IVT, MT rates: urban = 75.4%, 17.4%, 7.5% and rural = 67.1%; 15.4%, 5.3%, respectively). CONCLUSION: Hospitalized healthcare in Germany shows high treatment rates for both SU admission and acute recanalization treatment in patients with acute ischemic stroke; however, there is further optimization potential in rural regions.

Intravenous thrombolysis for large vessel or distal occlusions presenting with mild stroke severity.

BACKGROUND AND PURPOSE: We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points. METHODS: The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding. RESULTS: We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy. CONCLUSIONS: Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.

Atrophy of optic nerve detected by transorbital sonography in patients with demyelinating diseases of the central nervous system.

BACKGROUND AND PURPOSE: Transorbital sonography (TOS) has emerged as promising imaging method for the diagnosis and follow-up of acute optic neuritis (ON). Available studies report an increase in the optic nerve diameter (OND) and the optic nerve sheath diameter (ONSD) in the case of a first episode of ON in the affected eye compared to either the contralateral unaffected eye or controls. However, the utility of TOS in the case of recurrent episodes of ON has never been assessed. METHODS: In our prospective cohort study, the diagnostic utility of TOS in patients with demyelinating diseases of the central nervous system was assessed, and the association between TOS, optical coherence tomography (OCT) and visual evoked potentials was examined further. RESULTS: Seventy-eight patients with a history of demyelinating disorders of the central nervous system (mean age 38.2 ± 14.2 years; 24% with acute ON) were included. No differences in the OND (3.2 ± 0.5 mm vs. 3.2 ± 0.4 mm) and ONSD (5.1 ± 0.8 mm vs. 5.1 ± 0.7 mm) measurements were found between patients with and without acute ON. Papillary swelling was more frequent in patients with acute ON (14.2% vs. 1.5%, P = 0.002). Patients with a history of previous ON were found to have lower OND (P < 0.001) and ONSD (P = 0.007) compared to patients without a history of previous ON. TOS measurements were inversely associated with disease duration and positively correlated with OCT findings. No association with visual evoked potential measurements was found. CONCLUSION: No evidence was found for TOS-sensitive differences in the OND and ONSD of patients with demyelinating diseases, according to the presence of acute ON. The association between TOS and OCT measurements deserves further investigation.

Safety of urgent endarterectomy in acute non-disabling stroke patients with symptomatic carotid artery stenosis: an international multicenter study.

BACKGROUND AND PURPOSE: International recommendations advocate that carotid endarterectomy (CEA) should be performed within 2 weeks from the index event in symptomatic carotid artery stenosis (sCAS) patients. However, there are controversial data regarding the safety of CEA performed during the first 2 days of ictus. The aim of this international, multicenter study was to prospectively evaluate the safety of urgent (0-2 days) in comparison to early (3-14 days) CEA in patients with sCAS. METHODS: Consecutive patients with non-disabling (modified Rankin Scale scores ≤2) acute ischaemic stroke or transient ischaemic attack due to sCAS (≥70%) underwent urgent or early CEA at five tertiary-care stroke centers during a 6-year period. The primary outcome events included stroke, myocardial infarction or death during the 30-day follow-up period. RESULTS: A total of 311 patients with sCAS underwent urgent (n = 63) or early (n = 248) CEA. The two groups did not differ in baseline characteristics with the exception of crescendo transient ischaemic attacks (21% in urgent vs. 7% in early CEA; P = 0.001). The 30-day rates of stroke did not differ (P = 0.333) between patients with urgent (7.9%; 95% confidence interval 3.1%-17.7%) and early (4.4%; 95% confidence interval 2.4%-7.9%) CEA. The mortality and myocardial infarction rates were similar between the two groups. The median length of hospitalization was shorter in urgent CEA [6 days (interquartile range 4-6) vs. 10 days (interquartile range 7-14); P < 0.001]. CONCLUSIONS: Our findings highlight that urgent CEA performed within 2 days from the index event is related to a non-significant increase in the risk of peri-procedural stroke. The safety of urgent CEA requires further evaluation in larger datasets.

Thrombectomy in posterior circulation stroke: differences in procedures and outcome compared to anterior circulation stroke in the prospective multicentre REVASK registry.

BACKGROUND AND PURPOSE: In contrast to anterior circulation stroke (ACS), there is no evidence from randomized trials that mechanical thrombectomy (MT) with modern stent retrievers or thromboaspiration is safe and effective in posterior circulation stroke (PCS). METHODS: The present analysis was based on the prospective multicentre Registry on Revascularization in Ischemic Stroke Patients (REVASK) in Germany. Demographic data, periprocedural times and complications, recanalization rates, and functional outcome at discharge and after 3 months were compared between 139 consecutive patients with PCS (84.9% basilar artery, 16.5% vertebral artery and 4.3% posterior cerebral artery occlusion) and 961 patients with ACS treated with MT. RESULTS: Compared to ACS, PCS patients were significantly younger (65 vs. 69 years, P = 0.021) and had a lower median National Institutes of Health Stroke Scale (NIHSS) score at baseline (12 vs. 15, P = 0.024). Patients with PCS had a significantly longer time delay between symptom onset and both start and end of the MT procedure. Successful recanalization and thrombectomy passes did not significantly differ between the two groups. No symptomatic intracranial haemorrhage occurred in PCS compared to 3% in ACS (P = 0.010). The median NIHSS score at discharge was 3 in PCS and 4 in ACS. Favourable functional outcome at 3 months (modified Rankin Scale 0-2 38.0% vs. 42.6%, P = 0.392) and mortality (33.7% vs. 30.8%, P = 0.539) did not differ significantly between PCS and ACS. CONCLUSIONS: The study suggests that MT in PCS shows a lower risk of symptomatic intracranial haemorrhage and similar effectiveness compared to ACS. PCS patients also seem to benefit from MT started beyond 6 h after symptom onset.

[Characteristics and dynamics of inpatient treatment of patients with Parkinson's disease in Germany : Analysis of 1.5 million patient cases from 2010 to 2015]. / Charakteristika und Dynamik der stationären Behandlung von Parkinson-Patienten in Deutschland : Analyse von 1,5 Mio. Patientenfällen aus den Jahren 2010 bis 2015.

BACKGROUND: Parkinson's disease is the most common neurodegenerative movement disorder and the fastest-growing neurological disease in the world. The diagnostic spectrum, demographic characteristics, comorbidities and case number developments of inpatient treatment in Germany with resulting implications for patient care have so far been insufficiently investigated. METHODS: Data from the diagnosis-related groups (DRG) statistics were analyzed in patients with a main and secondary diagnosis of primary Parkinson's syndrome (PS), secondary PS or other degenerative disease of the basal ganglia. For the reporting years 2010-2015, the dataset comprised 1,520,366 patient cases from 413 districts/independent cities throughout Germany. RESULTS: In 2015, mostly patients with moderate and severe primary PS were hospitalized (64.7%) often exhibiting motor fluctuations as well as marked medical and psychiatric comorbidities. Vascular parkinsonism was the most frequent secondary PS (36.6%) and progressive supranuclear palsy was the leading diagnosis in the other disorders of the basal ganglia (51.9%). Primary PS as a secondary diagnosis was found in many internal medicine hospitalizations. The inpatient case numbers for primary PS increased significantly from the years 2010 to 2015 and rural regions were particularly affected. CONCLUSION: The number of inpatient cases of Parkinson's disease is greatly increasing in Germany and mainly affects patients with severe motor complications and secondary parkinsonian syndromes. Particularly in rural areas, there is a risk of overburdening the treatment infrastructure, so that both outpatient and inpatient sectors must be strengthened. A limitation of the study is the analysis of only DRG coded data, whose quality could be improved in subsequent examinations by comparison with the current diagnostic criteria of the specialist societies.

[Availability of mechanical thrombectomy for acute stroke : Analysis of the health care reality in Germany]. / Verfügbarkeit der mechanischen Thrombektomie bei akutem Hirninfarkt : Analyse der Versorgungsrealität in Deutschland.

BACKGROUND: Mechanical thrombectomy (MT) has become an evidence-based therapy for stroke patients with proximal vessel occlusion of the anterior cerebral circulation. Nationwide availability of MT for all eligible patients within the shortest possible time window is a major challenge. AIM OF THE STUDY: Nationwide analysis of the rates of systemic thrombolysis (STL) and MT in Germany according to region and hospital-based evaluation. METHODS: The evaluation involved data analysis of the diagnosis-related groups (DRG) statistics and structured quality reports of hospitals for 2010 and 2014. The rates and changes of STL and MT were evaluated in the 413 German districts with reference to the corresponding case number of patients with acute ischemic stroke. RESULTS: Nationwide recanalization treatment rates increased from 2010 to 2014 both for STL (from 8.0% to 11.6%) and MT (from 0.7% to 2.3%). High variations were observed depending on the patient's place of residence (STL = 3.4-36.7%, MT = 0-7.4%). In 2014 a total of 5526 MT were coded in a total of 244,757 ischemic strokes. A total of 134 hospitals with more than 2 MT per year were identified; however, 21% of the nationwide MTs were performed in only 7 hospitals with more than 100 MT/year. In 308 (75%) of the 413 districts, not a single MT was performed. CONCLUSION: Due to a narrow net of certified stroke units with nationwide availability of STL, excellent structural conditions for treatment of acute stroke patients are already established in Germany. With regard to the nationwide availability of MT, there is still a need for optimization. Despite the increasing number of hospitals providing MT as an emergency procedure, a trend toward large intervention centers with supraregional catchment areas can be observed.

[Treatment reality of internal carotid artery stenosis in Germany : requirement and reality in international comparison and in light of the current S3 guidelines]. / Versorgungsrealität von Karotisstenosen in Deutschland : Forderung und Wirklichkeit im internationalen Vergleich und im Lichte der aktuellen S3-Leitlinie.

BACKGROUND: Severe atherosclerotic extracranial carotid artery stenosis accounts for 5-10 % of all ischemic strokes. Currently, therapeutic recommendations are undergoing changes, particularly regarding the treatment of asymptomatic stenosis. Consolidated knowledge on the indications, nationwide distribution and numbers of cases are not available. Moreover, the impact and grade of implementation of the recently published national S3 guidelines on the reality of medical treatment remain unclear. METHODS: Analysis of administrative hospital data involving the diagnosis-related groups (DRG) statistics and structured quality reports for 2010 and 2013 to evaluate the procedural therapy trends concerning operative and interventional approaches for symptomatic and asymptomatic carotid artery stenoses. RESULTS: In Germany approximately 37,000 carotid endarterectomies (CEA) and approximately 5,000 carotid angioplasties with stenting (CAS) are carried out per year. Approximately 94 % of CEA and 62 % of CAS are performed in centers with more than 25 procedures per year. Only 33 % of CEA and 39 % of CAS are related to symptomatic stenosis. CONCLUSION: Mathematically, an undertreatment of symptomatic and an overtreatment of asymptomatic carotid artery stenoses become apparent. Efforts should be made to achieve inpatient medical treatment conforming to the national S3 guidelines, in particular to adequately reduce the risk of stroke recurrence in patients with atherosclerotic symptomatic carotid artery stenosis.

Safety of early endarterectomy in patients with symptomatic carotid artery stenosis: an international multicenter study.

BACKGROUND AND PURPOSE: Although the latest recommendations suggest that carotid endarterectomy (CEA) should be performed in symptomatic carotid artery stenosis (sCAS) patients within 2 weeks of the index event, only a minority of patients undergo surgery within the recommended time-frame. The aim of this international multicenter study was to prospectively evaluate the safety of early CEA in patients with sCAS in everyday clinical practice settings. METHODS: Consecutive patients with non-disabling acute ischaemic stroke (AIS) or transient ischaemic attack (TIA) due to sCAS (≥ 70%) underwent early (≤ 14 days) CEA at five tertiary-care stroke centers during a 2-year period. Primary outcome events included stroke, myocardial infarction (MI) or death occurring during the 30-day follow-up period and were defined according to the International Carotid Stenting Study criteria. RESULTS: A total of 165 patients with sCAS [mean age 69 ± 10 years; 69% men; 70% AIS; 6% crescendo TIA; 8% with contralateral internal carotid artery (ICA) occlusion] underwent early CEA (median elapsed time from symptom onset 8 days). Urgent CEA (≤ 2 days) was performed in 20 cases (12%). The primary outcomes of stroke and MI were 4.8% [95% confidence interval (CI) 1.5%-8.1%] and 0.6% (95% CI 0%-1.8%). The combined outcome event of non-fatal stroke, non-fatal MI or death was 5.5% (95% CI 2.0%-9.0%). Crescendo TIA, contralateral ICA occlusion and urgent CEA were not associated (P > 0.2) with a higher 30-day stroke rate. CONCLUSIONS: Our findings indicate that the risk of early CEA in consecutive unselected patients with non-disabling AIS or TIA due to sCAS is acceptable when the procedure is performed within 2 weeks (or even within 2 days) from symptom onset.

[Quality parameters in the treatment of acute stroke: comparison of various regional treatment concepts]. / Qualitätsparameter der akuten Schlaganfallversorgung: Gegenüberstellung unterschiedlicher regionaler Versorgungskonzepte.

BACKGROUND: The long-term prognosis of stroke patients is still dependent in particular on the timing of a correct diagnosis, immediate initiation of a suitable specific therapy and competent treatment in a stroke unit. Therefore, nationwide attempts are being made to establish a comprehensive coverage of the necessary specific competence and infrastructural requirements. Divergent regional circumstances and economic viewpoints determine the characteristics of the various healthcare concepts and the interplay between participating cooperation partners. This article compares the development with respect to three qualitative treatment parameters exemplified by four regional healthcare models during the time period 2008-2011. METHODS: The hospitalization rates for patients with transitory ischemic attacks, ischemic and hemorrhagic stroke, the case numbers for stoke unit treatment and the rates of systemic thrombolysis and mechanical thrombectomy in the regions of Berlin, the Ruhr Area, Ostwestfalen-Lippe and southeast Bayern (TEMPiS) are presented based on the data from the DRG statistical reports for the years 2008 and 2011. RESULTS: The average hospitalization rates for ischemic stroke patients (brain infarct ICD 163) in the time period from 2008 to 2011 were 294 per 100,000 inhabitants for the Ruhr Area, 257 per 100,000 inhabitants for Ostwestfalen-Lippe and 265 per 100,000 inhabitants each for Berlin and southeast Bayern. The complex stroke treatment quota for southeast Bayern in 2008 was 31 % and 47 % in 2011 and the respective quotas for the other regions studied were 42-44 % and 58-59 %. The rate of systemic thrombolysis in 2008 ranged between 4.2 % and 7.4 % and in 2011 the increase in the range for the 4 regions studied was between 41 % and 145 %. In 2011 the thrombectomy quota of 2 % in the Ruhr Area was the only one which was above the national average of 1.3 % of all brain infarcts. DISCUSSION: Stroke is a common disease in the four regions studied. For the established forms of therapy, complex treatment of stroke and systemic thrombolysis, the positive effect of structurally improved approaches in the four different regional treatment concepts could be confirmed during the course of the observational time period selected. Mechanical thrombectomy which is currently still considered to be an individual healing attempt, was used significantly more often in the Ruhr Area in 2011 than in the other three regions studied. A standardized referral procedure had previously been established in the metropolitan regions.

[Reality of acute stroke patient care in the metropolitan Ruhr area: status quo and perspectives of a stroke-specific network]. / Versorgungsrealität der Patienten mit ischämischem Schlaganfall im Ruhrgebiet : Aktueller Stand und Perspektiven einer fachspezifischen Vernetzung.

BACKGROUND: Networking structures are constructed to improve daily care of acute stroke patients, in the Ruhr area by the association of 26 neurological departments. Quality of care can be measured by the rate of stroke unit treatment and of thrombolysis. Epidemiological data are mainly derived from registers resulting in sparse insight into incidence and rate of specialized care in daily practice. METHODS: The study involved data analysis of diagnosis-related groups (DRG) statistics and structured quality reports for 2008 and 2010 for depiction of the quality of routine treatment. Aggregation of the number of cases for incidence, rate of stroke unit treatment and thrombolysis district, province, and nation wide were analyzed. RESULTS: In 5.2 million inhabitants, the incidence of ischemic stroke (ICD I63) was 296/100,000 in 2010 (district-wise range 244-364) and 56% of patients were treated on a stroke unit (range 18-80%; 2008: 43%, range 10-72%). The rate of thrombolysis (ICD I63) was 6.4% and 9.1% in 2008 and 2010 (2008 range 0-11.2%, 2010 range 3.9-18.0%), respectively, which was significantly above the provincial average in 10 out of 15 districts. DISCUSSION: Ischemic stroke is a common disease in the area and the quality of care (e.g. stroke unit treatment and thrombolysis rate) is above average. The heterogeneous character of the region allows an exemplary networking aiming for the improvement of routine patient care, e.g. by the implementation of homogeneous standards and structural measures for the implementation of novel therapies. The current analysis allows the identification of the potential for optimization and monitoring of any changes.

[Switching from clopidogrel hydrogen sulfate to clopidogrel besylate. Impaired antiplatelet effect in patients with ischemic stroke]. / Umstellung von Clopidogrel-Hydrogensulfat auf Clopidogrel-Besilat. Unzureichende plättchenhemmende Wirkung bei Patienten mit Hirninfarkt.

The use of antiplatelet medications, such as acetylsalicylic acid (ASA), a combination of dipyridamol with ASA and also clopidogrel, is of great importance for the secondary prevention of ischemic stroke or transient ischemic attacks. In addition to the known form of clopidogrel hydrogen sulfate (CHS) a further clopidogrel salt, clopidogrel besylate (CB), has also been available since May 2008. The presented case illustrates that in patients with a history of cerebrovascular disease the antiplatelet response of CB can be diminished in comparison to CHS. Therefore we recommend testing the antiplatelet effectiveness when changing patient medication from CHS to CB.

["Chronic cerebrospinal venous insufficiency" and multiple sclerosis: critical analysis and first observation in an unselected cohort of MS patients]. / "Chronische zerebrospinale venöse Insuffizienz" und Multiple Sklerose: Kritische Analyse und erste Untersuchungen an einem unselektierten MS-Kollektiv.

Currently, the hypothesis that altered venous hemodynamics might play a causative role in the pathogenesis of multiple sclerosis (MS) is being controversially discussed. This new "venous hypothesis" postulates that obstructions of the cervical venous system cause an increased pressure of the intracranial venous system and that in turn intracranial congestion disintegrates the blood-brain barrier initiating the inflammatory process in MS.The "venous hypothesis" is analyzed and evaluated with regard to the following aspects: first concerning the validity of published data, second with regard to the plausibility in view of the currently approved pathogenetic model of MS, and third with regard to the compatibility with preliminary neurosonological findings in a small but unselected cohort of patients at our department.The authors conclude that the "chronic cerebrospinal venous insufficiency (CCSVI)" cannot represent the exclusive pathogenetic factor in the pathogenesis of MS. In our cohort, only 20% of the patients fulfilled the required neurosonological features of CCSVI. So far, the pathogenetic relevance of these findings remains speculative. Thus, based on the current scientific position we cannot justify invasive "therapeutic" approaches, especially if they are performed outside of clinical trials.

Detection of cerebral perfusion abnormalities in acute stroke using phase inversion harmonic imaging (PIHI): preliminary results.

Phase inversion harmonic imaging (PIHI) with newer contrast agents can display parameters of cerebral perfusion either using the established ipsilateral approach, or the novel bilateral approach in which both hemispheres are assessed in one examination. The aim of this study was to evaluate the potential of PIHI in detecting pathological perfusion in acute stroke, using the bilateral approach. Patients with a hemispheric syndrome presenting within 12 hours after symptom onset were examined with PIHI (SonoVue; bolus kinetics, fitted model function) using the bilateral approach if possible. Semi-quantitative perfusion related parameters (time to peak intensity (TPI) and peak width (PW)) were evaluated, and results correlated to follow up cerebral computed tomography (CCT) scans. In these four preliminary cases (one ipsilateral, three bilateral), PIHI was able to identify the ischaemic region because the function could not be fitted to the data. In one case, there was a difference between a core region where no perfusion was seen, and a surrounding region where hypoperfusion was detected (prolonged TPI and reduced PW). PIHI was able to predict the localisation and size of the eventual infarction even if no early CCT signs were seen. Furthermore, in one case, a surrounding hypoperfused region was identified, where tissue survived after recanalisation of the initially occluded middle cerebral artery. Using the bilateral approach, two advantages in comparison with the ipsilateral approach were obvious: cortical structures could be evaluated, and only one examination was needed to compare unaffected (ipsilateral) with affected (contralateral) tissue. These results should be confirmed by more cases, and should also be correlated to acute perfusion/diffusion weighted MRI data.