Dexterous helical magnetic robot for improved endovascular access.

Treating vascular diseases in the brain requires access to the affected region inside the body. This is usually accomplished through a minimally invasive technique that involves the use of long, thin devices, such as wires and tubes, that are manually maneuvered by a clinician within the bloodstream. By pushing, pulling, and twisting, these devices are navigated through the tortuous pathways of the blood vessels. The outcome of the procedure heavily relies on the clinician's skill and the device's ability to navigate to the affected target region in the bloodstream, which is often inhibited by tortuous blood vessels. Sharp turns require high flexibility, but this flexibility inhibits translation of proximal insertion to distal tip advancement. We present a highly dexterous, magnetically steered continuum robot that overcomes pushability limitations through rotation. A helical protrusion on the device's surface engages with the vessel wall and translates rotation to forward motion at every point of contact. An articulating magnetic tip allows for active steerability, enabling navigation from the aortic arch to millimeter-sized arteries of the brain. The effectiveness of the magnetic continuum robot has been demonstrated through successful navigation in models of the human vasculature and in blood vessels of a live pig.

Endovascular therapy outcome in isolated posterior cerebral artery occlusion strokes: A multicenter analysis of the Swiss Stroke Registry.

PURPOSE: There is little data on the safety and efficacy of endovascular treatment (EVT) in comparison with intravenous thrombolysis (IVT) in acute ischemic stroke due to isolated posterior cerebral artery occlusion (IPCAO). We aimed to investigate the functional and safety outcomes of stroke patients with acute IPCAO treated with EVT (with or without prior bridging IVT) compared to IVT alone. METHODS: We did a multicenter retrospective analysis of data from the Swiss Stroke Registry. The primary endpoint was overall functional outcome at 3 months in patients undergoing EVT alone or as part of bridging, compared with IVT alone (shift analysis). Safety endpoints were mortality and symptomatic intracranial hemorrhage. EVT and IVT patients were matched 1:1 using propensity scores. Differences in outcomes were examined using ordinal and logistic regression models. FINDINGS: Out of 17,968 patients, 268 met the inclusion criteria and 136 were matched by propensity scores. The overall functional outcome at 3 months was comparable between the two groups (EVT vs IVT as reference category: OR = 1.42 for higher mRS, 95% CI = 0.78-2.57, p = 0.254). The proportion of patients independent at 3 months was 63.2% in EVT and 72.1% in IVT (OR = 0.67, 95% CI = 0.32-1.37, p = 0.272). Symptomatic intracranial hemorrhages were overall rare and present only in the IVT group (IVT = 5.9% vs EVT = 0%). Mortality at 3 months was also similar between the two groups (IVT = 0% vs EVT = 1.5%). CONCLUSION: In this multicenter nested analysis, EVT and IVT in patients with acute ischemic stroke due to IPCAO were associated with similar overall good functional outcome and safety. Randomized studies are warranted.

Coronary Heart Disease and an Incidental Parathyroid Carcinoma.

A 71-year-old woman was admitted with angina pectoris. During hospitalization she developed a myocardial infarction (NSTEMI). Laboratory results revealed a mild elevated troponin and an elevated calcium level (3.35 mmol/l). Subsequently, there was a decreased phosphate (0.36 mmol/l [normal 0.81-1.62 mmol/l]) as well as 16-fold elevated serum level of parathyroid hormone (PTH, 1156 ng/l [normal 10-73 ng/l]), indicating a primary hyperparathyroidism. Sonographically a thyroidal node was detected, not clearly demarcated (TIRADS 5). FNA showed a monomorphic, partial follicular cell population with an immunohistochemical positivity for PTH. Magnetic resonance imaging (MRI) showed a 5 cm large tumor at the right caudal pole of the thyroid with compression of the dorsolateral trachea without infiltration. Surgical removal with en bloc resection of the right hemithyroid with parathyroidectomy was performed. Postoperatively the PTH level dropped to 12.1 ng/l. Pathological examination revealed a 5 cm tumor with infiltration of the thyroid and a perineural invasion. The diagnosis of a presymptomatic parathyroid carcinoma could be established. The affirmative histopathological diagnosis of a parathyroid carcinoma can be challenging and is limited to tumors with evidence of invasive growth in adjacent structures such as the thyroid and/or soft tissue, perineural spaces, angioinvasion of capsular and/or extracapsular vessels, and/or documented metastases.

Susceptibility and Tumor Size Changes During the Time Course of Standard Treatment in Recurrent Glioblastoma.

BACKGROUND AND PURPOSE: Susceptibility-weighted magnetic resonance imaging (SWI) yields information regarding tumor biology (e.g., hemorrhage) of growing gliomas. SWI changes can also be observed as a consequence of treatment, for example radiation therapy. The aim of our study was to investigate how susceptibility changes occur during the time course after completion of standard treatment in newly diagnosed glioblastoma (GBM). METHODS: Eighteen GBM patients were retrospectively analyzed. After completion of therapy, imaging was performed every 3 months. MRI was analyzed at the following time points: after the third and sixth cycle of adjuvant temozolomide chemotherapy, thereafter in 3 month intervals and at recurrence. The number of SWI positive tumor pixels was quantified and compared with progression as defined by the RANO criteria on T2- and contrast-enhanced T1-weighted MRI sequences (T1-CE). RESULTS: The MRI interval between completion of the sixth chemotherapy cycle and last MRI before progression was 390 ± 292 days. Between the last MRI before progression and at progression a significant increase in SWI positive tumor pixels was observed (P = .012), whereas tumor size remained unchanged (RANO T2: P = .385; RANO T1-CE: P = .165). The number of SWI positive pixels remained unchanged between last MRI before progression until progression (P = .149), whereas RANO T2 and T1-CE showed tumor progression (interval 128 ± 69 days). CONCLUSIONS: SWI positive pixel count increases significantly prior to changes in tumor size (RANO). Our findings may be explained by microbleeds compatible with stimulation of angiogenesis and possibly serve as an early biomarker of tumor progression.

Modulation of the Emotional Response to Viewing Strabismic Children in Mothers-Measured by fMRI.

PURPOSE: Strabismus influences not only the individual with nonparallel eyes but also the observer. It has previously been demonstrated by fMRI that adults viewing images of strabismic adults have a negative reaction to the images as demonstrated by limbic activation, especially activation of the left amygdala. The aim of this study was to see if mothers would have a similar reaction to viewing strabismic children and whether or not that reaction would be different in mothers of strabismic children. METHODS: Healthy mothers of children with strabismus (n = 10, Group I) and without strabismus (n = 15, Group II) voluntarily underwent fMRI at 3T. Blood oxygen level dependent signal responses to viewing images of strabismic and non-strabismic children were analyzed. RESULTS: Group II, while viewing images of strabismic children, showed significantly increased activation of the limbic network (p < 0.05) and bilateral amygdala activation. Group I showed considerably less limbic activation, compared to the group II, and had no amygdala activation. Both groups revealed statically significant activation in the FEF (frontal eye field) when they were viewing images of strabismic children as compared to when they were viewing children with parallel eyes. The activated FEF area for Group II was much larger than for group I. CONCLUSION: Mothers of non-strabismic children showed similar negative emotional fMRI patterns as adults did while viewing strabismic adults. Strabismus is an interpersonal organic issue for the observer, which also impacts the youngest members of our society.

Relationship between the optic nerve sheath diameter and lumbar cerebrospinal fluid pressure in patients with normal tension glaucoma.

PurposeTo investigate on the relationship between the optic nerve sheath diameter (ONSD) and the lumbar cerebrospinal fluid pressure (CSF-p) in Caucasian patients with normal tension glaucoma (NTG).Patients and methodsRetrospective analysis of medical records of patients with open-angle glaucoma in the period from 2005 to 2015 from the Ophthalmology Department, Cantonal Hospital Aarau, Switzerland was performed. A total of 38 patients (mean age 68.6±11.3 years, 21 females and 17 males) fulfilled the diagnostic criteria of NTG and underwent computed tomography (CT) of the orbit and lumbar puncture (LP). In total, 38 age- and gender-matched Caucasian subjects (mean age: 68.9±10.9 years) without known ON diseases served as controls for ONSD measurements. ONSDs were measured at a distance of 3 mm from the posterior globe and lumbar CSF-p was related to the measurements. Statistical analysis was performed by using the independent two-tailed t-test and the non-parametric Spearman's correlation test.ResultsThe mean ONSD in NTGs measured 6.4±0.9 mm and in controls 5.4±0.6 mm. The difference between NTGs and controls showed statistical significance (t-test: P<0.000). The mean CSF-p in NTG was 11.6±3.7 mm Hg. There was no statistical significant correlation between ONSD and CSF-p (Spearman's correlation coefficient ρ=0.06, P=0.72).ConclusionsThis study demonstrates enlarged ONSDs and normal lumbar CSF-p in 38 Caucasian NTG patients. As enlarged ONSDs generally are associated with increased intracranial CSF-p, these results can be explained by a disturbed communication of CSF-p between the intracranial and intraorbital subarachnoid spaces.

Mechanical Thrombectomy Using the New ERIC Retrieval Device Is Feasible, Efficient, and Safe in Acute Ischemic Stroke: A Swiss Stroke Center Experience.

BACKGROUND AND PURPOSE: Intravenous thrombolysis and mechanical thrombectomy predominantly using stent retrievers have been shown to effectively restore cerebral blood flow and improve functional outcome in patients with acute ischemic stroke. We sought to determine the safety and feasibility of mechanical thrombectomy using the new ERIC retrieval device. MATERIALS AND METHODS: We identified 36 consecutive patients from our Stroke Center registry with acute ischemic stroke who were treated with the new ERIC retriever from September 2013 to December 2014. Patients with ischemic stroke meeting the following criteria were eligible: onset-to-treatment time of ≤4.5 hours or wake-up stroke (n = 10) with relevant CT perfusion mismatch, NIHSS score of ≥4, and proof of large-vessel occlusion in the anterior circulation on CT angiography. We assessed the baseline characteristics including age, sex, comorbidities, stroke severity, site of vessel occlusion, presence of tissue at risk, and treatment-related parameters such as onset-to-treatment time, recanalization grade, and outcome. RESULTS: The mean age was 70 ± 13 years, and the median NIHSS score on admission was 18 (interquartile range, 10-20). Seventeen of 36 patients were on platelet inhibitors or anticoagulants before endovascular treatment (47.2%); 20 patients received intravenous thrombolysis (55.5%). The ERIC was used as the sole retriever in 28 patients (77.8%) and as a rescue device in 8. Excellent recanalization was achieved in 30/36 patients (83.3%) with TICI 3 in 19/36 and 2b in 11/36, respectively. Median procedural time in these patients was 90 minutes (interquartile range, 58-133 minutes). No intraprocedural complications occurred. CONCLUSIONS: In this observational study, the new ERIC retrieval device was technically feasible, safe, and effective in acute ischemic stroke with large-vessel occlusion.

Effects of contour propagation and background corrections in different MRI flow software packages.

BACKGROUND: Velocity-encoded magnetic resonance imaging (VENC-MRI) is a commonly used technique in cardiac examinations. This technique utilizes the phase shift properties of protons moving along a magnetic field gradient. VENC-MRI offers a unique way of measuring the severity of valve regurgitation by directly quantifying the regurgitation flow volume. PURPOSE: To compare flow analysis results of different software programs and to assess the effect of background correction in sample patient cases. MATERIAL AND METHODS: A phantom was built out of Polymethyl methacrylate (PMMA) which provides tubes of different diameters. These tubes can be connected to an external water circuit to generate a water flow inside the tubes. Expected absolute flow quantities inside the tubes were determined from preset tube- and flow-parameters. Different flow conditions were measured with a VENC-MRI sequence and the images evaluated using different software packages. In a second step six randomly selected patients showing different degrees of aortic insufficiency were evaluated in clinical terms. RESULTS: The contour propagation algorithms used in the software packages performed differently even on static phantom geometry. In terms of clinical evaluation the software packages performed similarly. Enabling background correction or leaving out manual correction of propagated contours changed results for severity of aortic insufficiency. CONCLUSION: Turning on background correction and manual correction of propagated contours in MRI flow volume measurements is strongly recommended.

Susceptibility changes in meningiomas influence the apparent diffusion coefficient in diffusion-weighted MRI.

INTRODUCTION: Cell-dense tumors may restrict diffusivity which can be measured by diffusion-weighted MRI (DWI), and which is quantified by the apparent diffusion coefficient (ADC). Little is known about diffusivity in meningiomas. These tumors frequently show hemorrhage and calcification which can be demonstrated using susceptibility weighted MRI (SWI). Both DWI and SWI represent T2-derived MRI sequences. Here we investigated ADC variability in meningiomas and analyzed whether susceptibility changes (SWIpos) alter diffusivity. METHODS: We grouped newly diagnosed meningiomas according to the presence (SWIpos) or absence (SWIneg) of susceptibility changes. ADC values were calculated using region-of-interest analysis, and ADC values of SWIpos and SWIneg meningiomas were compared. In addition ADC histograms were created. RESULTS: We retrospectively studied 36 patients (13 WHO grade I, 8 WHO grade II, 15 suspected meningiomas). Thirteen meningiomas (36%) exhibited SWIpos. Global ADC values were higher in SWIpos (1.00 ± 0.15 × 10-3mm(2)/s) compared to SWIneg (0.82 ± 0.09 × 10-3mm(2)/s) tumors (P<0.0001). Meningiomas showing both SWIpos and SWIneg areas caused two separated histogram peaks, whereas homogeneously appearing meningiomas with either SWIposor SWIneg areas showed one peak only. ADC values did not correlate with age or gender, and showed substantial overlap between WHO grade I and II. CONCLUSION: Susceptibility changes (SWIpos) in meningiomas influence measures of diffusivity by increasing ADC values on average by 38%. This shift has to be considered when conclusions on tumor behavior are drawn from DWI. Further studies should address whether ADC changes and histogram patterns can be used to monitor treatment of meningiomas.

3D computerized occlusion rating of embolized experimental aneurysms using noninvasive 1.5T MR imaging.

BACKGROUND AND PURPOSE: For embolized cerebral aneurysms, the initial occlusion rate is the most powerful parameter to predict aneurysm rerupture and recanalization. However, the occlusion rate is only estimated subjectively in clinical routine. To minimize subjective bias, computer occlusion-rating (COR) was successfully validated for 2D images. To minimize the remaining inaccuracy of 2D-COR, COR was applied to 1.5T 3D MR imaging. MATERIALS AND METHODS: Twelve experimental rabbit aneurysms were subjected to stent-assisted coil embolization followed by 2D DSA and 3D MR imaging. Subjective occlusion-rate (SOR) was estimated. Linear parameters (aneurysm length, neck width, parent vessel diameter) were measured on 2D DSA and 3D MR imaging. The occlusion rate was measured by contrast medium-based identification of the nonoccluded 2D area/3D volume in relation to the total aneurysm 2D area/3D volume. 2D and 3D parameters were statistically compared. RESULTS: There were no limiting metallic artifacts by using 3D MR imaging. Linear parameters (millimeters) were nearly identical on 2D DSA and 3D MR imaging (aneurysm length: 7.5 ± 2.6 versus 7.4 ± 2.5, P = .2334; neck width: 3.8 ± 1.0 versus 3.7 ± 1.1, P = .6377; parent vessel diameter: 2.7 ± 0.6 versus 2.7 ± 0.5, P = .8438), proving the high accuracy of 3D MR imaging. COR measured on 3D MR imaging was considerably lower (61.8% ± 26.6%) compared with the following: 1) 2D-COR (65.6% ± 27.1%, P = .0537) and 2) 2D-SOR estimations (69.2% ± 27.4%, P = .002). These findings demonstrate unacceptable bias in the current clinical standard SOR estimations. CONCLUSIONS: 3D-COR of embolized aneurysms is easily feasible. Its accuracy is superior to that of the clinical standard 2D-SOR. The difference between 3D-COR and 2D-COR approached statistical significance. 3D-COR may add objectivity to the ability to stratify the risk of rerupture in embolized cerebral aneurysms.

Complex bilobular, bisaccular, and broad-neck microsurgical aneurysm formation in the rabbit bifurcation model for the study of upcoming endovascular techniques.

BACKGROUND AND PURPOSE: Despite rapid advances in the development of materials and techniques for endovascular intracranial aneurysm treatment, occlusion of large broad-neck aneurysms remains a challenge. Animal models featuring complex aneurysm architecture are needed to test endovascular innovations and train interventionalists. MATERIALS AND METHODS: Eleven adult female New Zealand rabbits were assigned to 3 experimental groups. Complex bilobular, bisaccular, and broad-neck venous pouch aneurysms were surgically formed at an artificially created bifurcation of both CCAs. Three and 5 weeks postoperatively, the rabbits underwent 2D-DSA and CE-3D-MRA, respectively. RESULTS: Mortality was 0%. We observed no neurologic, respiratory, or gastrointestinal complications. The aneurysm patency rate was 91% (1 aneurysm thrombosis). There was 1 postoperative aneurysm hemorrhage (9% morbidity). The mean aneurysm volumes were 176.9 ± 63.6 mm(3), 298.6 ± 75.2 mm(3), and 183.4 ± 72.4 mm(3) in bilobular, bisaccular, and broad-neck aneurysms, respectively. The mean operation time was 245 minutes (range, 175-290 minutes). An average of 27 ± 4 interrupted sutures (range, 21-32) were needed to create the aneurysms. CONCLUSIONS: This study demonstrates the feasibility of creating complex venous pouch bifurcation aneurysms in the rabbit with low morbidity, mortality, and high short-term aneurysm patency. The necks, domes, and volumes of the bilobular, bisaccular, and broad-neck aneurysms created are larger than those previously described. These new complex aneurysm formations are a promising tool for in vivo animal testing of new endovascular devices.

Cavernous malformations of the central nervous system in children: presentation, treatment and outcome of 20 cases.

BACKGROUND: Cavernous malformations (CM) of the central nervous system are vascular malformations responsible for symptoms such as seizures, headache, and neurological deficits: 25% of cases already present in childhood. MATERIAL AND METHODS: Retrospective study including all CMs of the central nervous system in childhood diagnosed in the period 1993-2008 in 3 paediatric hospitals in Switzerland, focusing on clinical manifestations, neuroimaging findings, treatment, and outcome. RESULTS: 20 children (13 females) were diagnosed with CM, with an average age at presentation of 8.5 years (range 7 months-16 years). 17/20 presented with acute haemorrhage, 9/17 with seizures, 5/17 with focal neurological symptoms, and 3/17 with severe headache only. Localisation was supratentorial in 15/20, infratentorial in 2/20, supra- and infratentorial in 2/20, and spinal in 1 child. Five children had multiple CMs. Treatment was conservative in 10 cases and surgery was indicated in 10: for acute haemorrhage in 5; recurrent bleeding in 3; and epilepsy in 2. Follow-up after diagnosis was 0.5 years-10 years (mean 4 years), revealing neurological sequelae in 6 patients. The CM increased in size in 2 cases with an increase in number also in 1 of these. CONCLUSIONS: We confirm that CMs in childhood mainly present with seizures, severe headache, or focal symptoms due to acute haemorrhage. During infancy they may appear as dynamic lesions increasing in size and/or number. The regular application of newer neuroimaging techniques such as susceptibility weighted imaging will detect more lesions but not necessarily resolve problems concerning optimum treatment.

Mapping of direction and muscle representation in the human primary motor cortex controlling thumb movements.

Larger body parts are somatotopically represented in the primary motor cortex (M1), while smaller body parts, such as the fingers, have partially overlapping representations. The principles that govern the overlapping organization of M1 remain unclear. We used transcranial magnetic stimulation (TMS) to examine the cortical encoding of thumb movements in M1 of healthy humans. We performed M1 mapping of the probability of inducing a thumb movement in a particular direction and used low intensity TMS to disturb a voluntary thumb movement in the same direction during a reaction time task. With both techniques we found spatially segregated representations of the direction of TMS-induced thumb movements, thumb flexion and extension being best separated. Furthermore, the cortical regions corresponding to activation of a thumb muscle differ, depending on whether the muscle functions as agonist or as antagonist for flexion or extension. In addition, we found in the reaction time experiment that the direction of a movement is processed in M1 before the muscles participating in it are activated. It thus appears that one of the organizing principles for the human corticospinal motor system is based on a spatially segregated representation of movement directions and that the representation of individual somatic structures, such as the hand muscles, overlap.

Real-time visualization of ultrasound-guided retrobulbar blockade: an imaging study.

BACKGROUND: Retrobulbar anaesthesia allows eye surgery in awake patients. Severe complications of the blind techniques are reported. Ultrasound-guided needle introduction and direct visualization of the spread of local anaesthetic may improve quality and safety of retrobulbar anaesthesia. Therefore, we developed a new ultrasound-guided technique using human cadavers. METHODS: In total, 20 blocks on both sides in 10 embalmed human cadavers were performed. Using a small curved array transducer and a long-axis approach, a 22 G short bevel needle was introduced under ultrasound guidance lateral and caudal of the eyeball until the needle tip was seen 2 mm away from the optic nerve. At this point, 2 ml of contrast dye as a substitute for local anaesthetic was injected. Immediately after the injection, the spread of the contrast dye was documented by means of CT scans performed in each cadaver. RESULTS: The CT scans showed the distribution of the contrast dye in the muscle cone and behind the posterior sclera in all but one case. No contrast dye was found inside the optic nerve or inside the eyeball. In one case, there could be an additional trace of contrast dye behind the orbita. CONCLUSIONS: Our new ultrasound-guided technique has the potential to improve safety and efficacy of the procedure by direct visualization of the needle placement and the distribution of the injected fluid. Furthermore, the precise injection near the optic nerve could lead to a reduction of the amount of the local anaesthetic needed with fewer related complications.

Clinical validation of an automated vessel-segmentation software of the extracranial-carotid arteries based on 3D-MRA: a prospective study.

OBJECTIVES: To determine the accuracy of automated vessel-segmentation software for vessel-diameter measurements based on three-dimensional contrast-enhanced magnetic resonance angiography (3D-MRA). METHOD: In 10 patients with high-grade carotid stenosis, automated measurements of both carotid arteries were obtained with 3D-MRA by two independent investigators and compared with manual measurements obtained by digital subtraction angiography (DSA) and 2D maximum-intensity projection (2D-MIP) based on MRA and duplex ultrasonography (US). In 42 patients undergoing carotid endarterectomy (CEA), intraoperative measurements (IOP) were compared with postoperative 3D-MRA and US. RESULTS: Mean interoperator variability was 8% for measurements by DSA and 11% by 2D-MIP, but there was no interoperator variability with the automated 3D-MRA analysis. Good correlations were found between DSA (standard of reference), manual 2D-MIP (rP=0.6) and automated 3D-MRA (rP=0.8). Excellent correlations were found between IOP, 3D-MRA (rP=0.93) and US (rP=0.83). CONCLUSION: Automated 3D-MRA-based vessel segmentation and quantification result in accurate measurements of extracerebral-vessel dimensions.

[Diagnosis and treatment of carotid cavernous fistulas]. / Carotis-Cavernosus-Fisteln: Diagnostik und Therapie.

This article provides an overview on the actual state of the interventional neuroradiological management of carotid cavernous fistulas depending on their anatomy and pathophysiology. The results are based on our experience gained during the treatment of patients with complex CCF during the last 15 years. Indications, procedures, and results of transarterial, transvenous and combined arteriovenous approaches for balloon occlusion, embolization, coiling and stenting of these lesions are discussed. Progress in this field is constant so that new technical advances are expected to improve the safety and to expand the indications for these procedures in the future.

Prospective navigator-echo-based real-time triggering of fetal head movement for the reduction of artifacts.

The purpose of this study was to evaluate the neuroimaging quality and accuracy of prospective real-time navigator-echo acquisition correction versus untriggered intrauterine magnetic resonance imaging (MRI) techniques. Twenty women in whom fetal motion artifacts compromised the neuroimaging quality of fetal MRI taken during the 28.7 +/- 4 week of pregnancy below diagnostic levels were additionally investigated using a navigator-triggered half-Fourier acquired single-shot turbo-spin echo (HASTE) sequence. Imaging quality was evaluated by two blinded readers applying a rating scale from 1 (not diagnostic) to 5 (excellent). Diagnostic criteria included depiction of the germinal matrix, grey and white matter, CSF, brain stem and cerebellum. Signal-difference-to-noise ratios (SDNRs) in the white matter and germinal zone were quantitatively evaluated. Imaging quality improved in 18/20 patients using the navigator echo technique (2.4 +/- 0.58 vs. 3.65 +/- 0.73 SD, p < 0.01 for all evaluation criteria). In 2/20 patients fetal movement severely impaired image quality in conventional and navigated HASTE. Navigator-echo imaging revealed additional structural brain abnormalities and confirmed diagnosis in 8/20 patients. The accuracy improved from 50% to 90%. Average SDNR increased from 0.7 +/- 7.27 to 19.83 +/- 15.71 (p < 0.01). Navigator-echo-based real-time triggering of fetal head movement is a reliable technique that can deliver diagnostic fetal MR image quality despite vigorous fetal movement.

Symptomatic intracranial haemorrhage after intra-arterial thrombolysis in acute ischaemic stroke: assessment of 294 patients treated with urokinase.

BACKGROUND: The PROACT II trial showed that intra-arterial thrombolysis (IAT) is effective for treatment of acute ischaemic stroke attributable to M1 and M2 segment occlusions. Incidence of symptomatic intracranial haemorrhage (sICH) was 10%. OBJECTIVE: To evaluate the risk and predictors of sICH after IAT by using urokinase in a large number of patients presenting with the whole spectrum of cerebral vessel occlusions. METHODS: 294 patients with stroke treated with intra-arterial urokinase were retrospectively analysed. The risk of sICH as well as bleeding characteristics were assessed. Demographic and radiological data, time to treatment, urokinase dose, recanalisation rates, stroke aetiology and severity were analysed for predictors. RESULTS: sICH occurred in 14 of 294 (4.8%) patients. The median National Institute of Health Stroke Scale score of all patients was 15. All but one sICH were located in the infarcted brain tissue, and no sICH occurred in patients with peripheral vessel occlusions (M3 or M4 segments of the middle cerebral artery). Poor collaterals (p = 0.001), early signs of ischaemia on computed tomography (p = 0.003), higher urokinase dose (p = 0.019), lower recanalisation rate (p = 0.02) and higher diastolic blood pressure on admission (p = 0.04) were found to be correlated with sICH on univariate analysis. On multivariate analysis, poor collaterals (p = 0.004), urokinase dose (p = 0.021) and early signs on computed tomography (p = 0.026) remained predictors of sICH. CONCLUSIONS: With regard to the whole spectrum of cerebral vessel occlusions, an incidence of <5% sICH after IAT is distinctly low. This result underlines the important role of IAT in the treatment of acute stroke.