Acute Glaucoma Following Internal Carotid Artery Stenting: A Rare But Serious Complication of Ocular Ischemic Syndrome.

Acute glaucoma following carotid artery recanalization is a rare but severe complication of underlying ocular ischemic syndrome. We present a case of a 71-year-old woman with ocular ischemic syndrome and severe stenosis of the right internal and external carotid artery undergoing carotid artery stenting. Immediate postprocedural angiography showed pronounced reperfusion of the ophthalmic artery. Subsequently, the patient developed vision-threatening acute glaucoma despite treatment with acetazolamide. Monitoring of intraocular pressure is important in patients who are at risk of developing ocular ischemic syndrome because of internal carotid artery stenosis. Interventionalists should also assess the degree of vascular collateralization from the external carotid artery.

Visualization of Liliequist's membrane prior to endoscopic third ventriculostomy.

PURPOSE: Endoscopic third ventriculostomy (ETV) is an effective treatment in patients with obstructive hydrocephalus caused by aqueductal stenosis. Operative failure may occur if an unnoticed membrane below the floor of the third ventricle is present, such as Liliequist's membrane (LM). To analyze how often LM can be visualized by high-resolution heavily T2-weighted 3D-MRI prior to ETV, and to find out potential reasons for diagnostic failure. MATERIALS AND METHODS: Preoperative 3D-MR images of 37 consecutive patients (19 female, median 42 years) were retrospectively analyzed. Visualization of three LM segments (sellar, diencephalic, mesencephalic), dimensions of the space below the third ventricle, and extent of hydrocephalus were measured. Image quality was scored (score 1[poor] to 3[excellent]). Preoperative imaging findings were compared with intraoperative findings. RESULTS: Patients were subdivided into group 1 (no segment of LM identified, n = 18), and group 2 (at least one segment of LM was identified, n = 19). The sellar segment of LM was most often positively identified (10 out of 19 cases). The mean distance between the pons and the sella/clivus was significantly shorter in group 1 than in group 2 (3.7 vs. 6.2 mm; p < 0.01). Other variables, such as the distance between tip of the pons and the mamillary bodies as well as the image quality, were not significantly different between both groups. Intraoperatively, LM was present in 78 % of group 2 patients, and in 28 % of group 1 patients, respectively (p < 0.03). CONCLUSIONS: LM can be detected in about half of patients prior to ETV. Reduced PSD influences visualization of LM.

Focal subarachnoid haemorrhage mimicking transient ischaemic attack--do we really need MRI in the acute stage?

BACKGROUND: Acute non-traumatic focal subarachnoid haemorrhage (fSAH) is a rare transient ischaemic attack (TIA)-mimic. MRI is considered to be indispensable by some authors in order to avoid misdiagnosis, and subsequent improper therapy. We therefore evaluated the role of CT and MRI in the diagnosis of fSAH patients by comparing our cases to those from the literature. METHODS: From 01/2010 to 12/2012 we retrospectively identified seven patients with transient neurological episodes due to fSAH, who had received unenhanced thin-sliced multiplanar CT and subsequent MRI within 3 days on a 1.5 T scanner. MRI protocol included at least fast-field-echo (FFE), diffusion-weighted imaging (DWI), T2-weighted fluid-attenuated inversion recovery (FLAIR) and time-of-flight (TOF) MRA sequences. By using MRI as gold-standard, we re-evaluated images and data from recent publications regarding the sensitivity to detect fSAH in unenhanced CT. RESULTS: fSAH was detected by CT and by FFE and FLAIR on MRI in all of our own cases. However, DWI and T2w-spin-echo sequences revealed fSAH in 3 of 7 and 4 of 6 cases respectively. Vascular imaging was negative in all cases. FFE-MRI revealed additional multiple microbleeds and superficial siderosis in 4 of 7 patients and 5 of 7 patients respectively. Including data from recently published literature CT scans delivered positive results for fSAH in 95 of 100 cases (95%), whereas MRI was positive for fSAH in 69 of 69 cases (100%). CONCLUSIONS: Thin-sliced unenhanced CT is a valuable emergency diagnostic tool to rule out intracranial haemorrhage including fSAH in patients with acute transient neurological episodes if immediate MRI is not available. However, MRI work-up is crucial and mandatorily has to be completed within the next 24-72 hours.

Mechanical thrombectomy in basilar artery thrombosis: technical advances and safety in a 10-year experience.

PURPOSE: Multiple endovascular devices have been used for mechanical thrombectomy (MT) in basilar artery occlusion (BAO) for >10 years. Based on a single-center experience during the course of one decade, we present data on safety and efficacy of previous MT devices compared with modern stent retriever and suction thrombectomy. MATERIALS AND METHODS: Eighty-one patients (29 women, 52 men, mean age 61.5 years, range 17-90) with angiographically confirmed BAO that had been treated by MT between 2001 and 2011 were retrospectively evaluated. Patients in group 1 (n = 60) had been treated between 2001 and 2008 with different devices available at that time. Patients in group 2 (n = 21) had been treated by modern stent retriever or local suction devices between 2008 and 2011. Recanalization rate, needle to recanalization time, procedure-related complications, and distal embolization of thrombotic material were recorded and compared. RESULTS: Recanalization rates of 95% were high in both groups. Procedure-related dissection (n = 5) and subarachnoid hemorrhage (n = 9) occurred in group 1 but not in group 2 (p < 0.016). Needle-to-recanalization time was less than half in group 2 compared with group 1 (54.6 vs. 132.3 min, p < 0.01). Frequency of distal embolization was comparable in both groups (47%). CONCLUSION: High recanalization rates have been achieved since the introduction of MT in BAO. However, modern stent retriever and suction devices allow for safer and more rapid recanalization compared with previous MT devices.

Current strategies in the diagnosis of diffuse large B-cell lymphoma of the central nervous system.

Lymphomas can arise within the central nervous system (CNS) as primary CNS lymphoma (PCNSL) typically involving the brain and less often the leptomeninges, eyes, and spinal cord. In contrast to PCNSL, secondary CNS lymphoma (SCNSL) is considered to originate as quasi metastasis from systemic lymphoma spreading to the CNS. Both types of CNS lymphomas are predominantly tumours of the diffuse large B-cell type and represent aggressive diseases necessitating a rapid diagnosis. Following neuroimaging based on magnetic resonance imaging, stereotaxy and histopathological diagnosis of CNS lymphoma currently remain obligatory to plan treatment. However, progress in cytopathological, immunophenotypic, and molecular genetic analyses of the cerebrospinal fluid (CSF) has been achieved recently and potentially will facilitate lymphoma diagnosis in the future. This review describes the diagnostic procedures in patients with suspected CNS lymphomas, primarily PCNSL. In addition to a summary of the standard diagnostic work-up, an overview and discussion of current data on different techniques for evaluation of the CSF in CNS lymphoma are given.

MRI patterns in recurrence of primary CNS lymphoma in immunocompetent patients.

PURPOSE: Primary CNS lymphomas (PCNSL) are highly malignant non-Hodgkin's B-cell lymphoma restricted to the CNS. While MRI features of PCNSL at initial presentation have been comprehensively described, literature on MRI-characteristics at relapse is sparse. The purpose of this study was to investigate anatomic location and contrast enhancement patterns at PCNSL recurrence by cranial MRI. METHODS: Sixteen immunocompetent patients (9 men, 7 women, median age 65 years) with histologically proven PCNSL and initial response to a standardized polychemotherapy, but suffering from a relapse were consecutively recorded. Native and contrast-enhanced MRI examinations carried out at initial presentation and at time of relapse were compared. Anatomical site of parenchymal enhancement, frequency and presence of non-parenchymal contrast enhancement (i.e. ventricular, superficial, subependymal) patterns at initial presentation and at relapse were recorded and compared. RESULTS: Local recurrence was found at the site of the initial tumor presentation in four of the 16 cases. Six of 11 patients presenting a unilateral PCNSL at initial presentation had a bilateral involvement at relapse. In two cases, recurrence appeared solely on the contralateral side without involvement of the hemisphere initially affected. At both dates, subependymal enhancement was the most often found non-parenchymal pattern (six at initial presentation, and five at relapse). The number of patients with a ventricular contrast enhancement increased from one at initial presentation to four at relapse. CONCLUSIONS: PCNSL tend to recur in different parenchymal anatomic sites as compared with the site of the initial tumor presentation. Contrast-enhancing non-parenchymal lesions are also frequent and might change their pattern at relapse.

Management of patients with transient ischemic attack is safe in an outpatient clinic based on rapid diagnosis and risk stratification.

BACKGROUND: Transient ischemic attack (TIA) patients are at high risk of short-term stroke, myocardial infarction and vascular death. Stroke risk is reduced by immediate treatment initialization. Stroke unit treatment is recommended for TIA patients. We established an outpatient TIA clinic to address the question whether outpatient evaluation of suspected TIA is safe. METHODS: TIA workup included cerebral imaging, duplex sonography, transcranial Doppler screening for patent foramen ovale, electrocardiography, blood tests, ABCD(2) score and ankle-brachial index within one day. TIA patients received secondary prophylaxis immediately. TIA patients fulfilling predefined criteria for high early stroke risk (ABCD(2) score ≥4 points and TIA within 72 h, symptomatic stenosis, newly detected atrial fibrillation, recurrent TIA) were referred to the stroke unit. The remaining patients were discharged home. 90-day telephone follow-up was obtained. RESULTS: 123 consecutive patients with suspected TIA (53 male, age 59 ± 17.2 years) were prospectively evaluated. TIA or minor stroke was diagnosed in 69 (56%), and TIA mimics in 54 (44%) patients. Median time from symptom onset to presentation was 48 h (1 h to 3 months). Patients with TIA/minor stroke presented significantly more frequently with ABCD(2) score ≥4 points (p = 0.021). Twelve patients (9.8%) were admitted to the stroke unit. There were 2 strokes during follow-up. The stroke rate was 1.6% within all patients, and 2.9% within the subgroup of patients with TIA/minor stroke, compared to 5.7% predicted by the ABCD(2) score. Other vascular end points were not found. CONCLUSION: Based on risk stratification, outpatient evaluation of TIA is safe. TIA mimics are frequent.

Three-dimensional constructive interference in steady-state magnetic resonance imaging in obstructive hydrocephalus: relevance for endoscopic third ventriculostomy and clinical results.

OBJECT: Endoscopic third ventriculostomy is the treatment of choice in patients with obstructive hydrocephalus caused by aqueductal stenosis. The authors examined the clinical course and results of surgical treatment for obstructive hydrocephalus with pre- and postoperative refined constructive interference in steady-state (CISS) MR imaging. METHODS: Forty patients with obstructive hydrocephalus underwent pre- and postoperative 3D-CISS imaging and clinical evaluation. Radiological findings were correlated with intraoperative observations of the thickness and transparency of the floor of the third ventricle and the patient's postoperative clinical course. RESULTS: Three-dimensional CISS MR imaging provides precise visualization of the basilar/posterior cerebral artery, its distance to the clivus, the diameter of the foramen of Monro, and the extension of and thickness of the floor of the third ventricle. In 71% of patients a flow void was detectable postoperatively on the ventriculostomy. In this group 81.5% had strong and 14.8% moderate clinical benefit, and 3.7% required secondary shunt placement. In the remaining 29% of the patients without a visible flow void, strong improvement was seen in 54.5%, moderate improvement in 18.2%, and stoma failure occurred in 27.3% (p = 0.094). Radiological measurements of the thickness of the third ventricle floor correlated with intraoperative findings (r = 0.35, p = 0.029). Comparison of outcomes showed a statistically significant tendency for a better outcome in patients with thin and easily perforated third ventricle floors (p = 0.04). CONCLUSIONS: Endoscopic ventriculostomy in patients with obstructive hydrocephalus is safe and mostly successful, and 3D-CISS MR imaging seems to be a valuable diagnostic method for precisely identifying the anatomy of relevant structures. Furthermore, 3D-CISS MR imaging allows judgment of the thickness of the third ventricle floor and display of the ventriculostomy/flow void, which are predictive for intraoperative course and clinical outcome.

Continuous intra-arterial nimodipine for the treatment of cerebral vasospasm.

Two patients with refractory symptomatic cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) were treated by continuous intra-arterial nimodipine infusion via a catheter placed in the internal carotid artery or vertebral artery for 3 and 12 days, respectively. Recovery of the neurological deficits, normalization of MR perfusion, a decrease in the elevated mean flow velocity measured by transcranial duplex sonography, and angiographic recanalization were observed. Continuous intra-arterial nimodipine might be a treatment option in severe refractory vasospasm following SAH.

Treatment of wide-necked intracranial aneurysms with a novel self-expanding two-zonal endovascular stent device.

INTRODUCTION: Endovascular treatment of intracerebral wide-necked aneurysms carries the risk of incomplete embolisation and recanalisation of the aneurysm as well as coil protrusion into the parent artery and embolic complications. We present preliminary results with the placement of a novel tightly braided stent across the aneurysm neck which might lead to thrombosis of these aneurysms. METHODS: A bifurcation artery aneurysm was created in a male New Zealand White Rabbit. After 4 weeks, a novel highly flexible stent with a central tightly braided mesh was placed across the aneurysm neck. Diagnostic angiography was performed during the procedure and immediately after stent deployment as well as 2 and 4 weeks following stent placement. Histological analyses, including microscopic investigations for evaluating intra-aneurysmal thrombosis and proliferation of the intima, were performed after 1 month. RESULTS: Intra-aneurysmal flow reduction due to stent placement was achieved as early as 45 min after deployment. Unchanged complete occlusion of the aneurysm could be observed by angiography 2 and 4 weeks post-stent deployment. Histological analysis confirmed angiographical findings of complete aneurysm occlusion and excluded significant neointimal coverage. CONCLUSION: This newly designed flexible stent may offer the potential to expand endovascular treatment of wide-necked intracranial aneurysms.

Functional outcome after severe cerebral venous thrombosis.

Severe cerebral venous thrombosis (CVT) is a rare cerebrovascular condition which in the more severe cases warrants intensive care treatment. While the outcome in the majority of uncomplicated CVT cases is good, it may be fatal in more affected patients. We provide long-term functional and quality of life (QOL) outcome data in the form of a retrospective analysis of 10 patients admitted to a neurological ICU with severe CVT. Outcome measures used were the modified Rankin Scale, the 36-item Short Form Health Survey, and the Psychological General Well-Being index. The mortality rate was 50% but 4 out 5 survivors had a good functional outcome with normal QOL despite a very severe clinical course. This finding justifies extensive life-sustaining therapy as the prognosis even of severe cases may be good if the acute phase is survived.

A multicenter, site-independent, blinded study to compare the diagnostic accuracy of contrast-enhanced magnetic resonance angiography using 1.0M gadobutrol (Gadovist) to intraarterial digital subtraction angiography in body arteries.

PURPOSE: Prospective evaluation of diagnostic accuracy of single field-of-view contrast-enhanced MR Angiography (ceMRA) with 1.0M gadobutrol compared to intraarterial DSA in body arteries. MATERIALS AND METHODS: In an European multicenter study 179 patients underwent ceMRA and DSA. For each indication five prospectively defined vessel segments were evaluated by local investigators onsite and by three site-independent blinded readers (BR) independently. RESULTS: The agreement between ceMRA and DSA diagnosis was statistically significant in the onsite (96.6%) and blinded reader (86.6-90.2%) evaluation. Sensitivity, specificity, accuracy, positive (PPV) and negative predictive values (NPV) for detection of relevant stenosis (>50%) were calculated for the right and left internal carotid arteries, and common and external iliac arteries: Sensitivity was 95-98% (onsite) and 76-96% (BR), specificity 94-96% (onsite) and 86-94% (BR), accuracy 96% (onsite) and 87-93% (BR), NPV 98-99% (onsite) and 84-98% (BR), and PPV 79-93% (onsite) and 44-91% (BR), respectively. CONCLUSION: CeMRA of body arteries using 1.0M gadobutrol provides diagnostic information comparable to intraarterial DSA.

Stent-angioplasty of intracranial vertebral and basilar artery stenoses in symptomatic patients.

BACKGROUND: To present our two-center treatment results with stent angioplasty of intracranial vertebrobasilar stenoses in symptomatic patients. MATERIAL AND METHODS: Between 2001 and 2003, 21 patients with 22 stenoses, refractory to medical therapy, who underwent elective stenting of intracranial vertebrobasilar stenoses were retrospectively analyzed. All patients had ischemic events clinically referable to the stenoses. Only high-grade stenoses of at least 80% were treated. Clinical evaluation was done based on the modified ranking scale (MRS). RESULTS: In all cases, the stent deployment turned out to be technically successful and control angiography demonstrated the elimination of the high-grade stenoses. A minor residual stenoses was still detectable in six cases. According to the MRS, clinical outcome improved in the case of four patients, seemed unchanged in 14 and worsened in three. The clinical morbidity rate amounted to 14%. Clinical follow-up was available for 13 patients after 9 months with no recurrent symptoms and angiographic follow-up was available after 10 months. Re-stenoses occurred in two cases without clinical symptoms. Retreatment was not done. CONCLUSION: According to our data, stent angioplasty for symptomatic intracranial vertebrobasilar stenoses can be a treatment alternative in case of recurrent symptoms despite medical therapy; particularly, for stenoses of type Mori A or B.

Extent of spontaneous cross-flow via the anterior communicating artery in steno-occlusive carotid artery disease.

PURPOSE: Our purpose was to evaluate the agreement of transcranial color-coded duplex sonography (TCCS) measurements and intra-arterial digital subtraction angiography (DSA) findings in determining the extent of spontaneous cross-flow via the anterior communicating artery (AcoA) in patients with internal carotid artery (ICA) stenosis. METHODS: Thirty adult patients with suspected uni- or bilateral high-grade carotid artery stenosis were prospectively examined by DSA and angle-corrected TCCS. The extent of cross-flow was determined considering retrograde flow in the ipsilateral anterior cerebral artery (ACA) and sideto-side differences of the A1-segments of the ACA and middle cerebral arteries (MCAs) by both techniques. Cross-flow was angiographically categorized by means of a four-step scale. DSA findings were correlated with side-to-side differences in mean blood flow velocity as well as flow direction measured by TCCS. RESULTS: Twenty-seven of 30 patients had a uni- or bilateral ICA stenosis of >49%. Excellent agreement between TCCS and DSA was evaluated for the detection of lack (grades 0 and 1) or presence (grades 2 and 3) of reversed flow in the ACA (sensitivity 100%, specificity 93%, positive predictive value 94%). Post hoc analysis of the mean velocities in the ACA and MCA revealed a side-to-side difference of 25 cm/s as a cutting point allowing for definition of a corresponding four-grade scale for ultrasound. However, full agreement, i.e.same grade of cross-flow detected by both techniques, was only found in 17(57%) of 30 cases. CONCLUSIONS: Non-invasive TCCS is reliable for detecting reversed flow in the ACA in patients with ICA stenosis. However, there is only a moderate agreement between angiography and TCCS in quantifying the extent of spontaneous anterior cross-flow because different information on the intracranial hemodynamics may be obtained.

Treatment of vertebrobasilar occlusion by using a coronary waterjet thrombectomy device: a pilot study.

BACKGROUND AND PURPOSE: Despite improved patient outcomes because of intraarterial fibrinolysis, vertebrobasilar thromboembolism remains a fatal disease with a death rate of more than 50%. The outcome depends on the success of recanalization. Fibrinolysis achieves recanalization in only 50%-70% of the cases. Therefore, we investigated the feasibility of using a coronary mechanical device to increase the recanalization rate. METHODS: Twelve patients with acute vertebrobasilar occlusion were included in the pilot study. The older 5F and the new 4F versions of the Possis Angiojet catheter, which use a waterjet to attract, fragment, and extract the thrombus, were used. Inclusion depended on the presence of acute multisegmental intracranial or any extracranial vertebrobasilar occlusion. Exclusion criteria included coma lasting >8 hours and age >80. The Angiojet treatment did not exclude other therapeutic options. RESULTS: The Angiojet catheter accessed the thrombosed site in 10 of 12 patients. Combined treatment with the Angiojet and additional fibrinolysis or angioplasty resulted in a recanalization rate of 100%. Of 37 occluded vertebrobasilar segments, 30 were primarily recanalized with the Angiojet. Three symptomatic and two asymptomatic hemorrhages were detected by CT. Five of the 12 patients died. Fifty percent of all patients obtained a moderate to excellent outcome (Modified Rankin Scale 0-3). CONCLUSIONS: Use of the coronary Angiojet in the vertebrobasilar system is feasible. The device has the potential to increase the recanalization rate, especially in cases of extensive thrombosis, and, thus, improve patient outcomes.