The learning curve for interventional cardiologists performing acute stroke interventions

Background

Endovascular treatment for acute stroke because of large vessel occlusion became the standard of care in certain clinical settings. Due to lack of trainees and specialized centers, interventional cardiologists joined multidisciplinary stroke teams, and contribute their extensive knowledge on acute cardiovascular interventions and catheter skills to optimize patient management and outcomes.

Purpose

To investigate if a learning curve exists for interventional cardiologists performing acute stroke interventions.

Methods

Consecutive patients undergoing acute endovascular stroke treatment from 07/2012 – 10/2020 at our center were reviewed. The interventional approach, lesion preparation and material selection were at the discretion of the performing cardiologist. Baseline characteristics, procedural information and in-hospital outcomes were retrospectively collected. Cases were chronologically sorted, divided into quartiles and outcomes were compared.

Results

One-hundred-thirteen patients underwent endovascular procedures for acute stroke treatment. Patients were 72.9 SD 13.3 years old, and 51.5% were female. NIHSS at baseline was 15 [12–18]. In 92% the blood flow of the anterior circulation was affected. The door to needle (DTN) time decreased over time (Q1 1:19h [range0:54–1:58] vs. Q2 0:49h [range 0:34–1:32] vs. Q3 1:13h [range 0:56–1:31] vs. Q4 0:54 [range 0:37–1:08], p=0.003), as well as the procedure duration (time of vascular access to (full) reperfusion Q1 1:24h [range 0:44–2:23] vs. Q2 0:52h [range 0:32–1:16] vs. Q3 0:49h [range 0:27–1:15] vs. 0:44h [range 0:28–1:17], p=0.014) and the use of contrast medium (Q1 103.3mL [range 75.1–147.7] vs. Q2 123.5mL [range 60.5–149.9] vs. Q3 99.8mL [range 73–132] vs. Q4 74.8 mL [range 52.4–94.6], p=0.014). A stent retriever only strategy was preferred in the early stages (Q1 42.8% vs. Q2 53.5% vs. Q3 32.1% vs. Q4 17.2%. p=0.010), whereas a stent retriever plus aspiration strategy (Q1 17.8% vs. Q2 14.2% vs. Q3 28.5% vs. Q4 50%, p=0.122) became more popular later on. The combined quality endpoint comprising of TICI IIb/III flow after the procedure, no embolization to new territories and no symptomatic intracranial bleeding was reached 84%, with no difference between groups. Vascular access site complications were low (overall 3.5%) and NIHSS prior to discharge was comparable (Q1 3 [range 1.75–7.25] vs. Q2 4.5 [range 1.75–8.25] vs. Q3 5 [range 2–8] vs. Q4 4 [range 2–7], p=0.725). In-hospital death occurred in 21 (18.5%) patients.

Conclusions

A learning curve for interventional cardiologist performing acute stroke interventions could be observed in terms of optimized management strategies such as a reduced door to needle time and procedural aspects, like decreased procedure duration and contrast medium use over time. However, the quality of care was unaffected and continuously high.

Funding Acknowledgement

Type of funding sources: None.

Regular hours vs. on-call endovascular interventions for acute stroke treatment: initial single-center experience by interventional cardiologists

Background

Endovascular treatment for acute stroke with large vessel occlusion became the mainstay therapy but remains limited due to lack of trainees and specialized centers. To offer this therapeutical option to a vast population, interventional cardiologists joined interdisciplinary stroke teams. Because of limited experience, it remains unclear if the timing of the procedure (i.e., regular hours vs. on-call time) may influence quality, time-effectiveness and outcomes.

Purpose

To investigate if the timing of the procedure (i.e., regular hours vs. on-call time) significantly influences procedural parameters and outcomes of patients undergoing acute endovascular stroke treatment.

Methods

Consecutive patients undergoing acute endovascular stroke treatment from 07/2012 – 10/2020, treated by cardiologists, were reviewed. Baseline characteristics, procedural aspects and clinical outcomes were retrospectively collected. Cases were divided into two groups, depending on the timing of the procedure: on-call time (OC, i.e., weekend days, public holidays and documented “call in” of the on-call service) vs. regular hours (RH, i.e., all other procedures) and outcomes subsequently compared.

Results

One-hundred-thirteen consecutive patients underwent endovascular treatment for acute stroke; of those 77 (68.1%) during regular hours and 36 (31.9%) during on-call time. Patients were in their early 70ies and risk factors such as arterial hypertension, diabetes mellitus, dyslipidemia and atrial fibrillation were evenly distributed. Modified Ranking Scale (mRS) at presentation was 5 in both groups and decreased to 3 at discharge. The anterior circulation was most often affected (RH: 90.9% vs. OC: 94.4%, p=0.518) and a stent retriever only strategy commonly chosen (RH: 42.8% vs. OC: 30.5%, p=0.211), followed by a combined approach of stent retriever use and aspiration (RH: 25.9% vs. OC: 27.7%, p=0.752). Door-to-needle time (RH: 0:55h IQR [0:45–1:22] vs. OC: 1:05h IQR [0:54–1:30], p=0.237) and procedure duration (RH: 0:48h IQR [0:30–1:25] vs. OC: 0:58h IQR [0:35–1:46], p=0.214) were comparable. Contrast agent use and radiation time (RH: 17.6 min IQR [11.7–29.3] vs. OC: 17.6 min IQR [12.1–33.6]) did not differ between groups, however patients in the OC group experienced a higher dose area product (RH: 4827mGy cm2 IQR [1567–14092] vs. 12727mGy cm2 [6732–18889], p<0.001). The combined quality endpoint, comprising of TICI IIb/III flow after the procedure, no embolization to new territory and no symptomatic intracranial bleeding during in hospital stay was met in 85.5% of patients in the RH group and 80.5% of the on-call group (p=0.485). Death during in-hospital stay was observed in 22% of patients in the RH group and 11.1% of the OC group (p=0.163).

Conclusions

Endovascular intervention for acute stroke treatment during on-call time is as effective and safe as if performed during regular hours but associated with a higher dose area product.

Funding Acknowledgement

Type of funding sources: None.

Acute stroke intervention for acute embolic procedural strokes performed by cardiologists

Acute ischemic stroke is a feared complication during cardiovascular procedures associated with high morbidity and mortality if not immediately recognized and treated. We conducted a review of cases at our center where patients experienced an acute, procedure-related ischemic stroke and underwent immediate endovascular stroke treatment by the interventional cardiologists trained in acute endovascular stroke intervention. Baseline demographics, procedural and follow-up data were collected. Three patients were identified in whom the percutaneous procedure (peripheral arterial intervention, transapical NeoChord [NeoChord Inc, Minnesota, USA] implantation and transcatheter aortic valve implantation, respectively) was complicated by an acute embolic ischemic stroke. In all cases, cerebral vessel re-canalization was technically successful with thrombolysis in cerebral infarction (TICI) IIB/III flow. Follow-up computed tomography scans showed no infarct demarcation, oedema or intracranial hemorrhage. One patient survived with no neurological symptoms at 6-month follow-up whereas the two other patients died of unrelated intensive care complications and decompensated heart failure. We conclude that endovascular stroke treatment during cardiovascular interventions can be performed by interventional cardiologists with appropriate training. It offers the unique opportunity to treat cerebral embolization in a time-efficient manner, potentially improving morbidity and mortality of affected patients.

Post-Market Clinical Follow-Up With the Patent Foramen Ovale Closure Device IrisFIT (Lifetech) in Patients With Stroke, Transient Ischemic Attack, or Other Thromboembolic Events

BACKGROUND

A patent foramen ovale (PFO) has been associated with embolic strokes and transient ischemic attacks (TIAs). Catheter closure of PFO is effective in preventing recurrent events. Residual shunts and procedure or device related complications can occur, including atrial fibrillation and thrombus formation. This study examines the initial experience with a new PFO closure device, the IrisFIT PFO-Occluder (Lifetech Scientific, Shenzhen, China).

METHODS

95 patients with indications for PFO closure underwent percutaneous closure with the IrisFIT PFO-Occluder. The primary endpoint was the rate of accurate device placement with no/small residual shunt at 3 or 6 months follow-up. All patients underwent transoesophageal echocardiography (TEE) after 1 to 6 months. In case of a residual shunt, an additional TEE was performed after 12 months. Clinical follow-up was performed up to a mean of 33.1 ± 3.6 months.

RESULTS

The device was successfully implanted in 95 (100%) patients with no relevant procedural complications. At final TEE follow-up (7.6 ± 3.9 months) the effective closure rate was 96.8% with 1 moderate and 2 large residual shunts. There were 8 cases of new onset atrial fibrillation and 2 TIAs. There were no cases of device embolization or erosion.

CONCLUSION

The IrisFIT occluder is a new PFO closure device with several advantages compared to other devices. In this small study cohort, technical success rate, closure rate and adverse event rate were comparable to other devices. The rate of new onset atrial fibrillation was higher in comparison to other studies and warrants further investigation.

Outcomes following endovascular therapy for acute stroke by interventional cardiologists

OBJECTIVES

To summarize the outcomes of acute ischemic stroke (AIS) intervention by interventional cardiologists (IC) working on a stroke team.

BACKGROUND

There is a geographic maldistribution of dedicated neuro-interventionalists (NI) to treat large vessel occlusion (LVO) AIS.

METHODS

Results of 166 consecutive patients who received endovascular therapy (EVT) for AIS due to LVO by IC at three centers between 2009 and 2019 are reported. A modified Rankin score (mRs) of ≤ 2 at 90 days after EVT was used as the primary measurement of a good neurological outcome. Univariate logistic regression was used to evaluate predictors of the mRS > 2 and mortality. Those variables with significance of p < .2 from the univariate analysis were included in a multivariate analysis.

RESULTS

All-cause mortality at 30 days was 22%. A favorable clinical outcome, mRS ≤ 2 at 90 days, was 49%. After multivariate analysis and controlling for confounders, a higher baseline NIHSS was predictive of 30-day mortality (OR 1.20 [95% CI 1.09-1.32] p < .001) and unfavorable clinical outcome (mRS > 2) at 90 days (OR 1.16 [95% CI 1.07-1.25] p < .001).

CONCLUSION

Outcomes for carotid stent capable IC performing EVT for AIS are comparable to those achieved by NI physicians in major randomized clinical trials. Our data supports conducting a clinical trial of carotid stent capable IC working on multidisciplinary stroke teams to perform EVT for AIS due to LVO in communities and hospitals without timely access (<60 min by ground transport) to dedicated NI.

The IrisFIT Patent Foramen Ovale Closure Device in Patients With History of Cryptogenic Embolization

BACKGROUND

The aim of this study was to assess safety, efficacy, and clinical outcome of the IrisFIT PFO Closure System (Lifetech Scientific) for transcatheter closure of patent foramen ovale (PFO) in patients with a history of cryptogenic stroke, transient ischemic attack (TIA), or peripheral embolization.

PATIENTS AND METHODS

We report the results of 60 consecutive patients undergoing PFO closure with the IrisFIT occluder for secondary prevention of paradoxical embolization. All cases were analyzed for periprocedural and device-related adverse events up to 12 months after implantation. In addition, the patients were evaluated for complete defect closure with transesophageal echocardiography (TEE) after 1 month, 6 months, and (if indicated) 12 months. Mean patient age was 53 ± 14 years and 37 patients (62%) were males. All patients had a history of at least 1 cryptogenic stroke, TIA, or peripheral embolization.

RESULTS

Technical success was achieved in all 60 procedures. The mean procedure time was 28 ± 11 minutes. There were no periprocedural or device-related complications up to 12 months after the implant. Successful defect closure at 6 months post device implantation was achieved in 56 cases (93.3%). Within 12 months of follow-up, 2 patients had recurrent TIAs, both with complete PFO sealing at the last TEE prior to the event.

CONCLUSION

The IrisFIT PFO Closure System can be used safely and with high technical success for secondary prevention of cryptogenic stroke or peripheral embolization.

Endovascular Therapy for Acute Ischemic Stroke: A Comprehensive Review of Current Status

Stroke remains among the leading causes of disability and death worldwide. Fibrinolytic therapy is associated with poor patency and functional outcomes. Recently, multiple randomized trials have been published that have consolidated the role of endovascular therapy for ischemic stroke due to large vessel occlusion in the anterior cerebral circulation. This manuscript reviews the current understanding of the endovascular management of acute stroke including technical aspects and current evidence base.

Abstract WP3: Occluded Vessel Location is a Predictor of Clinical Outcome in the Natural History of Acute Ischemic Stroke From Large Vessel Occlusion Eligible for Mechanical Thrombectomy

Purpose: The preponderance of evidence suggests that target vessel locations (TVL) are important predictors of outcomes in acute ischemic stroke (AIS). However, few studies have examined in detail their correlation in the natural history of a cohort of patients with ICA, M1 and M2 vessel occlusions who are eligible for, but untreated with, mechanical thrombectomy.

Hypothesis: We hypothesize that, similar to the broader stroke cohort, there is a correlation between TVL and outcomes.

Methods: The SOS and FIRST trials were prospective, multicenter studies evaluating the natural history of a stroke cohort eligible for mechanical thrombectomy but did not receive the treatment. Enrolled patients presented with symptoms of AIS due to LVO and were refractory or ineligible for rtPA treatment. Functional independence was defined as a mRS score 0-2 at 90 days. Incidence of death, intracranial hemorrhage (ICH), serious adverse events (SAEs), and mortality were assessed for association with TVL.

Results: A total of 238 patients (median age: 71) met study criteria. Occlusions were reported in the ICA (32.5%), M1 (54.4%), M2 (8.9%), and basilar artery (1.7%). At 90 days, 9.2% of ICA, 12.1% of MCA M1, 25.0% of MCA M2, and 0.0% of basilar artery patients achieved functional independence as defined by a mRS score of 0-2. Although the rate of SAEs was similar between ICA (83.3%), M1 (81.4%), and basilar artery (75%), the rate was lowered in patients with M2 occlusion (61.9%, p<0.05). There were also significantly fewer mortalities associated with occlusion of the M1 (27.4%, p<0.01) and M2 (10.0%, p<0.01) when compared to ICA occlusions (40.8%).

Conclusion: Similar to the broader patients with AIS, there is a significant correlation between TVL and outcomes in patients with LVO eligible for mechanical thrombectomy. Although occlusion of smaller vessels (i.e. M2) predicts better functional outcome, 75% of patients will not reach functional independence.

Giant crystals inside mitochondria of equine chondrocytes

The present study reports for the first time the presence of giant crystals in mitochondria of equine chondrocytes. These structures show dark contrast in TEM images as well as a granular substructure of regularly aligned 1-2 nm small units. Different zone axes of the crystalline structure were analysed by means of Fourier transformation of lattice-resolution TEM images proving the crystalline nature of the structure. Elemental analysis reveals a high content of nitrogen referring to protein. The outer shape of the crystals is geometrical with an up to hexagonal profile in cross sections. It is elongated, spanning a length of several micrometres through the whole cell. In some chondrocytes, several crystals were found, sometimes combined in a single mitochondrion. Crystals were preferentially aligned along the long axis of the cells, thus appearing in the same orientation as the chondrocytes in the tissue. Although no similar structures have been found in the cartilage of any other species investigated, they have been found in cartilage repair tissue formed within a mechanically stimulated equine chondrocyte construct. Crystals were mainly located in superficial regions of cartilage, especially in joint regions of well-developed superficial layers, more often in yearlings than in adult horses. These results indicate that intramitochondrial crystals are related to the high mechanical stress in the horse joint and potentially also to the increased metabolic activity of immature individuals.

First protein and peptide characterization of the tarsal adhesive secretions in the desert locust, Schistocerca gregaria, and the Madagascar hissing cockroach, Gromphadorhina portentosa

Peptides and proteins have been largely neglected in the analysis of insect tarsal adhesives. After extraction of the protein fraction of the tarsal secretion of the desert locust, Schistocerca gregaria, and Madagascar hissing cockroach, Gromphadorhina portentosa, we combined Fourier transform infrared spectroscopy (FTIR), sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) analyses for protein mass detection. In both these insects, SDS-PAGE analysis revealed several protein bands ranging from 8-190 kDa in both the tarsal secretion and the tibia control sample. Two (S. gregaria) and one (G. portentosa) protein bands exclusively occurred in the tarsal secretion and can be considered to belong to peptides and proteins specific to this secretion. MALDI-TOF analyses revealed 83 different proteins/peptides of 1-7 kDa in S. gregaria, and 48 of 1-11 kDa in G. portentosa. 59 (S. gregaria) and 27 (G. portentosa) proteins exclusively occurred in the tarsal secretion. In G. portentosa, a characteristic series of signal peaks occurred in the range of c. 10-12 kDa, each peak being approximately 160 Da apart. Such a pattern is indicative of proteins modified by glycosylation. Our approach demonstrates that extensive sampling involving considerable time and manpower to sample the adhesive fluid directly from the tarsi opens up a perspective for extracting peptides and proteins in sufficient quantities. This makes them accessible to the field of proteomics and thus to elucidate their possible function in the adhesive process.

Oligodendrogliomas: A comparison of CT and MR imaging features with histological malignancy grading in 20 cases: A pathoradiological study

Purpose: To study the pattern of contrast enhancement in MR and CT of oligodendrogliomas and to compare this with other imaging findings and with histopathological grading criteria.

Material and Methods: 20 patients with oligodendrogliomas (12 low-grade WHO II and 8 anaplastic WHO III) were reviewed. 20 complete MR investigations, 20 non-enhanced CT studies and 16 CTs after contrast enhancement were estimated blindly without knowledge of the tumour histological grades.

Results: All anaplastic oligodendrogliomas showed tumour contrast enhancement on MR and CT images. Also in 6/12 low-grade oligodendrogliomas the contrast was enhanced on MR imaging. In 5 of these, tumour calcifications were detected by CT. The remaining 6/12 WHO grade II cases showed no significant MR contrast enhancement. Of the oligodendrogliomas grade II, CT showed contrast uptake in 3 cases and no enhancement in 6, while in 3 cases postcontrast CT was not available. A comparison of contrast enhancement with tumour grade resulted in a p-value of 0.042 for MR and of 0.011 for CT. A combined statistical test of tumour grade and calcifications detected by CT compared with MR contrast enhancement showed a significant correlation ( p=0.014).

Conclusion: These data demonstrated that a clear grading of oligodendrogliomas based on the image criterion MR contrast enhancement was not possible. We suppose that, besides tumour neovascularisation, additional factors such as calcifications may disturb the blood-brain barrier.

Initial Experience Using the Gore Embolic Filter in Carotid Interventions

BACKGROUND

This is the first clinical report on experience in the use of the Gore embolic filter in carotid interventions. It was designed as a guidewire and embolic protection system in carotid, peripheral, and coronary interventions. The ability to capture debris is driven by the frame of the filter, which is designed to improve vessel wall apposition and allows a short landing zone.

METHODS

We report the results of the first 20 consecutive patients undergoing carotid artery stenting using the Gore embolic filter in our institution. We analyzed technical success as well as the occurrence of transient ischemic attack (TIA), stroke, or death periprocedurally and through 30 days of follow-up. Mean patient age was 72 years and 12 patients (60%) were male. Seven patients were symptomatic and 4 patients suffered recurrent neurological events.

RESULTS

Technical success was achieved in all procedures. In 1 patient, the retrieval catheter was caught between the proximal struts of the stent and required further retrieval maneuvers. Within 30 days of follow-up, 1 patient had a TIA. No stroke, death, or myocardial infarction occurred.

CONCLUSION

This initial experience suggests that the Gore embolic filter device can be used safely for distal embolic protection during carotid stenting procedures with high technical success.

‘Stroke Room': Diagnosis and Treatment at a Single Location for Rapid Intraarterial Stroke Treatment

Background: For patients with acute ischemic stroke, intra-arterial treatment (IAT) is considered to be an effective strategy for removing the obstructing clot. Because outcome crucially depends on time to treatment (‘time-is-brain' concept), we assessed the effects of an intervention based on performing all the time-sensitive diagnostic and therapeutic procedures at a single location on the delay before intra-arterial stroke treatment. Methods: Consecutive acute stroke patients with large vessel occlusion who obtained IAT were evaluated before and after implementation (April 26, 2010) of an intervention focused on performing all the diagnostic and therapeutic measures at a single site (‘stroke room'). Result: After implementation of the intervention, the median intervals between admission and first angiography series were significantly shorter for 174 intervention patients (102 min, interquartile range (IQR) 85-120 min) than for 81 control patients (117 min, IQR 89-150 min; p < 0.05), as were the intervals between admission and clot removal or end of angiography (152 min, IQR 123-185 min vs. 190 min, IQR 163-227 min; p < 0.001). However, no significant differences in clinical outcome were observed. Conclusion: This study shows for the, to our knowledge, first time that for patients with acute ischemic stroke, stroke diagnosis and treatment at a single location (‘stroke room') saves crucial time until IAT.

In vitro experiments of cerebral blood flow during aspiration thrombectomy: potential effects on cerebral perfusion pressure and collateral flow

Background

Mechanical thrombectomy with stent retriever devices is associated with significantly better outcomes than thrombolysis alone in the treatment of acute ischemic stroke. Thrombus aspiration achieves high patency rates, but clinical outcomes are variable. The aim of this study was to examine the effect of different suction conditions on perfusate flow during aspiration thrombectomy.

Methods

A computational fluid dynamics model of an aspiration device within a patent and occluded blood vessel was used to simulate flow characteristics using fluid flow solver software. A physical particulate flow model of a patent vessel and a vessel occluded by thrombus was then used to visualize flow direction and measure flow rates with the aspiration catheter placed 1–10 mm proximal of the thrombus, and recorded on video.

Results

The mathematical model predicted that, in a patent vessel, perfusate is drawn from upstream of the catheter tip while, in an occluded system, perfusate is drawn from the vessel proximal to the device tip with no traction on the occlusion distal of the tip. The in vitro experiments confirmed the predictions of this model. In the occluded vessel aspiration had no effect on the thrombus unless the tip of the catheter was in direct contact with the thrombus.

Conclusions

These experiments suggest that aspiration is only effective if the catheter tip is in direct contact with the thrombus. If the catheter tip is not in contact with the thrombus, aspirate is drawn from the vessels proximal of the occlusion. This could affect collateral flow in vivo.

Abstract 194: Preliminary Results from the FIRST Trial: Natural History of Acute Stroke from Large Vessel Occlusion

Purpose: Current literature has limited information on the natural history of the stroke cohort eligible for mechanical thrombectomy. The placebo group from the PROACT II study is often used as a historical control, despite differences in entry criteria. Reported herein are data in a stroke cohort eligible for mechanical thrombectomy but untreated due to unavailability or inability to initiate endovascular treatment within the 8-hr window due to delayed presentation. The goal is to compare the functional independence rate with the PROACT placebo group.

Methods: The FIRST Trial is a prospective, multicenter, natural history study of a stroke cohort eligible for but untreated by mechanical thrombectomy presenting within 8 hrs of symptom onset from a large vessel occlusion and a NIHSS of at least 10. The primary endpoint is functional outcome at 90 days as defined by a mRS 0-2. Results are reported from an interim analysis.

Results: Fifty-nine (59) patients were enrolled and met study criteria for this interim analysis. The mean age was 68.2 ± 17 years; median NIHSS was 18 (5-34). Target vessel occlusions were in the ICA (35.7%), MCA (60.7%), and other (3.6%). At admission, the TIMI 0-1 rate was 89% (49/55), and the TICI 0-1 rate was 89% (48/54). Of these, only 10% (3/30) showed spontaneous recanalization (TIMI 2-3 or TICI 2a-3). Eleven of 55 (20%) patients achieved a good 90-day outcome, and 24 of 59 (40.7%) died. The serious adverse event rate was 52.6% (30/57), including respiratory failure (8 cases) and pneumonia (4 cases). A total of 6 (10%) patients suffered intracerebral hemorrhage (ICH). Below is a comparison of the MCA cohort vs. PROACT II placebo patients.

Conclusion: Compared with PROACT II placebo patients, the stroke cohort eligible for mechanical thrombectomy who were untreated have a lower rate of recanalization and worse outcome. These results indicate it may not be appropriate to use the PROACT placebo patients as historical controls for mechanical thrombectomy trials.

Mobile stroke unit for diagnosis-based triage of persons with suspected stroke

BACKGROUND

In this feasibility study, we tested whether prehospital diagnostic stroke workup enables rational decision-making regarding treatment and the target hospital in persons with suspected stroke.

METHODS

A mobile stroke unit that delivers imaging (including multimodal brain imaging with CT angiography and CT perfusion), point-of-care-laboratory analysis, and neurologic expertise directly at the emergency site was analyzed for its use in prehospital diagnosis-based triage of suspected stroke patients.

RESULTS

We present 4 complementary cases with suspected stroke who underwent prehospital diagnostic workup that enabled direct diagnosis-based treatment decisions and reliable triage regarding the most appropriate medical facility for that individual, e.g., a primary hospital vs specialized centers of a tertiary hospital.

CONCLUSIONS

This preliminary report demonstrates the feasibility of prehospital diagnostic stroke workup for immediate etiology-specific decision-making regarding the necessary time-sensitive stroke treatment and the most appropriate target hospital.

Diagnosis and treatment of patients with stroke in a mobile stroke unit versus in hospital: a randomised controlled trial

BACKGROUND

Only 2-5% of patients who have a stroke receive thrombolytic treatment, mainly because of delay in reaching the hospital. We aimed to assess the efficacy of a new approach of diagnosis and treatment starting at the emergency site, rather than after hospital arrival, in reducing delay in stroke therapy.

METHODS

We did a randomised single-centre controlled trial to compare the time from alarm (emergency call) to therapy decision between mobile stroke unit (MSU) and hospital intervention. For inclusion in our study patients needed to be aged 18-80 years and have one or more stroke symptoms that started within the previous 2·5 h. In accordance with our week-wise randomisation plan, patients received either prehospital stroke treatment in a specialised ambulance (equipped with a CT scanner, point-of-care laboratory, and telemedicine connection) or optimised conventional hospital-based stroke treatment (control group) with a 7 day follow-up. Allocation was not masked from patients and investigators. Our primary endpoint was time from alarm to therapy decision, which was analysed with the Mann-Whitney U test. Our secondary endpoints included times from alarm to end of CT and to end of laboratory analysis, number of patients receiving intravenous thrombolysis, time from alarm to intravenous thrombolysis, and neurological outcome. We also assessed safety endpoints. This study is registered with ClinicalTrials.gov, number NCT00153036.

FINDINGS

We stopped the trial after our planned interim analysis at 100 of 200 planned patients (53 in the prehospital stroke treatment group, 47 in the control group), because we had met our prespecified criteria for study termination. Prehospital stroke treatment reduced the median time from alarm to therapy decision substantially: 35 min (IQR 31-39) versus 76 min (63-94), p<0·0001; median difference 41 min (95% CI 36-48 min). We also detected similar gains regarding times from alarm to end of CT, and alarm to end of laboratory analysis, and to intravenous thrombolysis for eligible ischaemic stroke patients, although there was no substantial difference in number of patients who received intravenous thrombolysis or in neurological outcome. Safety endpoints seemed similar across the groups.

INTERPRETATION

For patients with suspected stroke, treatment by the MSU substantially reduced median time from alarm to therapy decision. The MSU strategy offers a potential solution to the medical problem of the arrival of most stroke patients at the hospital too late for treatment.

FUNDING

Ministry of Health of the Saarland, Germany, the Werner-Jackstädt Foundation, the Else-Kröner-Fresenius Foundation, and the Rettungsstiftung Saar.

Point-of-care laboratory halves door-to-therapy-decision time in acute stroke

Currently, stroke laboratory examinations are usually performed in the centralized hospital laboratory, but often planned thrombolysis is given before all results are available, to minimize delay. In this study, we examined the feasibility of gaining valuable time by transferring the complete stroke laboratory workup required by stroke guidelines to a point-of-care laboratory system, that is, placed at a stroke treatment room contiguous to the computed tomography, where the patients are admitted and where they obtain neurological, laboratory, and imaging examinations and treatment by the same dedicated team. Our results showed that reconfiguration of the entire stroke laboratory analysis to a point-of-care system was feasible for 200 consecutively admitted patients. This strategy reduced the door-to-therapy-decision times from 84 ± 26 to 40 ± 24 min (p < 0.001). Results of most laboratory tests (except activated partial thromboplastin time and international normalized ratio) revealed close agreement with results from a standard centralized hospital laboratory. These findings may offer a new solution for the integration of laboratory workup into routine hyperacute stroke management.

[Cavernous malformations]

Cavernomas of the CNS may involve brain parenchyma as well as the spinal cord and belong to those cerebrovascular malformations that have no arteriovenous shunt and thus are generally angiographically occult. Contrary to computed tomography (CT), which is generally suited to reveal calcifications or acute bleeding, magnetic resonance imaging (MRI) enables detection of even small cavernomas. A frequently associated venous anomaly is helpful for correct diagnosis.

[Sellar tumors]

Because of the complex anatomy, examination of the sella turcica and hypophysis needs a dedicated MR sequence protocol. Not every sellar lesion is a pituitary adenoma. Thus, this review article summarizes the most frequently encountered intra-, supra-, and parasellar tumors and lesions. Differential diagnoses comprise besides adenoma among others craniopharyngioma, meningioma, glioma, germinoma, hamartoma, aneurysm, trigeminal schwannoma, pituitary carcinoma, chordoma, metastasis, infection, and empty sella. Characteristic imaging findings are presented and correlated to micro- and macro-pathology.

[Supratentorial tumors]

Magnetic resonance imaging is a routine diagnostic measure for a suspected intracerebral mass. Computed tomography is usually also indicated. Further diagnostic procedures as well as the interpretation of the findings vary depending on the tumor location. This contribution discusses the symptoms and diagnostics for supratentorial tumors separated in relation to their intra- or extracranial location. Supratentorial tumors include astrocytoma, differentiated by their circumscribed and diffuse growth, ganglioglioma, ependyoma, neurocytoma, primitive neuroectodermal tumors (PNET), oligodendroglioma, dysem-bryoplastic neuroepithelial tumors (DNET), meningoangiomatosis, pineal tumors, hamatoma, lymphoma, craniopharyngeoma and metastases. The supratentorial extracranial tumors include the choroid plexus, colloid cysts, meningeoma, infantile myofibromatosis and lipoma. The most common sub-forms, especially of astrocytoma, will also be presented.

[Spinal infections]

Regardless of the compartment involved, imaging of spinal infections and other spinal inflammatory diseases must be performed by magnetic resonance imaging (MRI). This allows early detection of changes in disk space or vertebral bodies. Associated paraspinal and epidural masses are depicted. However, in spinal cord inflammation MRI has a very limited specificity and cannot usually differentiate between the wide array of possible causes of intramedullary lesions. This article covers a spectrum of inflammatory lesions of the spinal cord.

[Stroke]

Today stroke represents a major medical and political problem in Western industrial nations. High demands need to be placed on the initial diagnostic work-up and therapeutic treatment to ensure that the patients benefit from the recent advancements achieved in diagnostic and therapeutic fields. According to the motto "time is brain" the clinical examination and imaging have to be performed within 60 min ("door to needle time") so that potential patients can be quickly treated with systemic or intra-arterial lysis. However, it should be taken into consideration that the selection of diagnostic imaging facilities depends on several factors such as infrastructure, the time remaining in the diagnostic window, and the severity of the clinical symptoms.

[Imaging of spinal tumors]

Spinal tumors are often categorized into extradural, intradural extramedullary, or intramedullary. Although this classification represents somewhat of an overgeneralization as a lesion may reside in two compartments, it still helps to characterize spinal tumors. In the intradural, extramedullary space, primary tumors, such as neurofibroma and meningioma, are relatively common. Secondary tumors or leptomeningeal enhancement also occur. In the intramedullary space, primary tumors are far more common than secondary tumors or metastases.

[Spondylitis/spondylodiscitis]

Spondylitis is an inflammation of the vertebral body. If the infection is manifested in the vertebral motor segment it is called spondylodiscitis, which can be divided into specific and nonspecific forms. It is clinically impressive that at the beginning of the disease, the patients who are quite often immunosuppressed suffer from localized, especially nocturnally exacerbated backache. The initial diagnostic work-up generally consists of clinical history, examination, laboratory tests, and (especially advanced) imaging findings. Although computed tomography still remains the most frequently used advanced imaging technique, magnetic resonance imaging is the golden standard for the diagnosis of spondylitis and spondylodiscitis.

[Skull base tumors]

Modern imaging techniques have great importance in the diagnosis and therapy of skull-base pathologies. Many of these lesions, especially in relation to their specific location, can be evaluated using CT and MR imaging. Tumors commonly found in the anterior skull base include carcinoma, rhabdomyosarcoma, esthesioneuroblastoma and meningioma. In the central cranial fossa, nasopharyngeal carcinoma, metastases, meningioma, pituitary adenoma and neurinoma have to be considered. The most common neoplasms of the posterior skull base, including the CP angle, are neurinoma, meningioma, nasopharyngeal carcinoma, chordoma and paraganglioma. One major task of imaging is the evaluation of the exact tumor extent as well as its relationship to the neighboring neurovascular structures. The purpose of this review is to recapitulate the most important anatomical landmarks of the skull base. The typical imaging findings of the most common tumors involving the skull base are also presented.

Anatomie des Kleinhirnbrückenwinkels

The cerebellopontine angle (CPA) is an anatomically complex region of the brain. In this article we describe the anatomy of the CPA cisterns, of the internal auditory canal, the topography of the cerebellum and brainstem, and the neurovascular structures of this area.

[Spinal intradural tumors]

Spinal intradural tumors are uncommon lesions but may cause significant morbidity. In establishing the differential diagnosis for a spinal lesion, location, age, and the patient's clinical presentation are important. Magnetic resonance imaging plays a central role in the visualization of spinal tumors, easily allowing tumors to be classified as extradural, intradural extramedullary, or intramedullary which is very useful in tumor characterization. We describe intradural tumors; the majority is extramedullary, with nerve sheath tumors being the most frequent. Intramedullary tumors are uncommon spinal tumors. Ependymomas and astrocytomas comprise the majority of this group. Typical imaging features of both intradural extramedullary and intramedullary tumors are described.

Behandlung der arteriosklerotischen Karotisstenose: ein �berblick

Endarterectomy for extracranial carotid stenosis has proven to be the method of choice for symptomatic patients suffering from ischemia (NASCET, ECST). The effectivity of the operation for asymptomatic stenosis seems to be likely since the publication of the first results of the ACST trial. The safety and efficiency of carotid stenting has not been proven so far and has to be evaluated in randomized trials comparing surgery and endovascular treatment. We provide an overview of the current trials and try to define the role of carotid stenting.

MRI of the brainstem in patients with major depression, bipolar affective disorder and normal controls

Structural imaging studies of bipolar affective disorder or major depression have shown a spectrum of abnormal findings. However, a characteristic pattern of abnormality for either disease has not yet emerged. While the majority of studies focused on brain atrophy and the volumes of supratentorial cerebral structures, little attention has been paid to infratentorial structures. This MRI study focused on the pontomesencephalic area including the region of the raphe nuclei. The raphe nuclei are of special interest in affective disorders as they are the origin of the major serotonergic projections in this region. MRI scans of 10 bipolar I patients, 10 patients with major depression and 10 age-matched healthy control subjects were studied. The brain stem and the fourth ventricle areas as well as T2-relaxation times in the area of the raphe nuclei were evaluated. A difference between patients with major depression and control subjects for T(2)-relaxation times was found in a region of interest located along the midline of the pons. No difference was found between patients with bipolar disorder and control subjects. This finding needs to be replicated in a larger sample with more elaborated MRI techniques (multi-echo sequences) for the determination of T2-relaxation times.

[Craniocerebral trauma in childhood]

This article describes typical head injuries in infants and children. In comparison with adults there are distinct differences in the etiology of trauma and in the kind of reaction of the skull and brain. In infants and children there are three different types of trauma: birth trauma, accidental and non-accidental injury. The typical injuries in these three groups are described.