[Visual rating of T2'-blood-oxygen-level-dependent magnetic resonance imaging in acute stroke patients--a pilot study]. / T2'-Blood-Oxygen-Level-Dependent-Magnetresonanz-Bildgebung beim akuten Schlaganfall--eine Pilotstudie.

PURPOSE: Delineation of brain tissue that is at risk but not yet infarcted (penumbra) continues to be a major challenge for stroke imaging. Metabolic characterization of the penumbra might be able to be achieved using blood-oxygen-level-dependent (BOLD) imaging. MATERIALS AND METHODS: We analyzed MRI data from 20 patients within the first 6 hours after stroke onset and after 5-8 days. Among other sequences, the MRI protocol consisted of diffusion-weighted (DWI/ADC = apparent diffusion coefficient) and quantitative T2 and T2* imaging (qT2, qT2*). BOLD images (T2') were calculated using 1/T2' = 1/qT2* - 1/qT2. BOLD lesions were rated by two blinded observers. RESULTS: Based on the primary blinded reading of the BOLD images, the lesion side was rated correctly by observers 1 and 2 in 80/50 % of the cases, incorrectly in 5/40 % of the cases, and rated as not visible in 15/10 % of the cases. After unblinding the observers, the visibility was rated in 45/45 % of the cases as good, in 35/40 % of the cases as reasonable, and in 20/15 % of the cases as insufficient for diagnostic purposes. The sensitivity for subsequent infarct growth was 0.88 (95 % confidence interval, CI 0.47 to 0.99), the specificity was 0.33 (95 % CI 0.07 to 0.70), the positive predictive value (PPV) was 0.54 (95 % CI 0.25 to 0.81), and the negative predictive value (NPV) was 0.75 (95 % CI 0.19 to 0.99). The odds ratio for subsequent infarct growth was 3.5 (95 % CI 0.20 to 115.53). CONCLUSION: Hypo-intense lesions in BOLD imaging were visible and exceeded the lesion in diffusion-weighted imaging in most of the stroke patients. The encouraging results justify further testing of the hypothesis that BOLD lesions, when larger than DWI lesions, are associated with infarct growth from initial DWI to final infarct.

The amount of solid cerebral microemboli during carotid stenting does not relate to the frequency of silent ischemic lesions.

BACKGROUND AND PURPOSE: Carotid artery stent placement (CAS) may be associated with clinically silent cerebral lesions. We prospectively evaluated the association of the number of solid cerebral microemboli during unprotected CAS with the frequency of silent cerebral lesions as detected by diffusion-weighted MR imaging (DWI). METHODS: We performed multifrequency transcranial Doppler detection of solid microemboli in the ipsilateral middle cerebral artery (MCA) during CAS in 27 consecutive patients with symptomatic high-grade carotid stenoses. No embolus protection was used in any of the cases. DWI before and 24 +/- 2 hours after CAS was used to detect new ischemic lesions. RESULTS: We detected 484 solid microemboli in 17 patients (63%). On MR imaging 24 +/- 2 hours after CAS, 6 patients (22%) had developed 13 new clinically silent DWI lesions within the ipsilateral MCA territory. In patients with Doppler evidence of solid emboli during CAS, the incidence of new DWI lesions was higher (29%) than in patients without Doppler evidence of solid emboli during the procedure (10%); this difference was not statistically significant (P = .25). The number of solid microemboli during CAS in patients with new ipsilateral DWI lesions was not significantly different from that in patients without new ipsilateral DWI lesions. CONCLUSIONS: Solid microembolism is a common event during unprotected CAS; however, the frequency of procedure-related silent cerebral lesions appears to be independent of the number of solid cerebral microemboli during the procedure.

Disarrangement of fiber tracts and decline of neuronal density correlate in glioma patients--a combined diffusion tensor imaging and 1H-MR spectroscopy study.

BACKGROUND AND PURPOSE: Diffusion tensor imaging (DTI) and MR spectroscopy are noninvasive, quantitative tools for the preoperative assessment of gliomas with which the quantitative parameter fractional anisotropy (FA) and the concentration of neurometabolites N-acetylaspartate (NAA), choline (Cho), creatine (Cr) of the brain can be determined. Measurements of FA and NAA reflect the integrity of fiber tracts and the presence of neurons, respectively. This investigation examines changes of FA and NAA and compares these different aspects in architecture of gliomas after spatial coregistration. METHODS: DTI and chemical shift (1)H-MR spectroscopy was performed in 34 healthy volunteers and 69 patients with histologically confirmed (n = 48) or morphologically suspected (n = 21) non-necrotic brain glioma. Volumes of interest (VOIs) were placed in the tumor center (TC), the tumor border (TB), the normal-appearing white matter adjacent to the tumors (TNWM), and in the white matter of the contralateral hemisphere (NWMC). Median FA values and NAA/Cr and NAA/Cho ratios were calculated in the patients' VOIs and the gray and white matter of the volunteers. Correlations of FA values and NAA ratios were calculated. RESULTS: Continuous changes of FA and NAA from the tumor center to the periphery (the adjacent white matter and the contra-lateral hemisphere, respectively) were observed, where median values were: TC: 0.73 +/- 0.45, 0.47 +/- 0.58, 0.17 +/- 0.15 (NAA/Cr, NAA/Cho, FA); TB: 1.06 +/- 0.53, 1.00 +/- 0.15, 0.23 +/- 0.08; TNWM: 1.42 +/- 2.48, 1.21 +/- 0.95, 0.34 +/- 0.09; and NWMC: 1.63 +/- 0.72, 1.56 +/- 1.34, 0.38 +/- 0.08. Correlation of median FA values and NAA ratios in the cumulative group of patients was high (r = 0.99 [NAA/Cr], 0.95 [NAA/ Cho] at P < .01). Correlation between the individual NAA ratios and the FA values was moderate (r = 0.53 [NAA/Cr], 0.51 [NAA/Cho] at P < .01). CONCLUSION: In gliomas, the degree of tissue organization decreases continuously from the surrounding tissue toward the center of the tumor accompanied by a concordant decrease of NAA. This uniform behavior of FA and NAA reflects a decreasing integrity of both neuronal structures and fibers.

Motor cortex excitability after cerebellar infarction.

BACKGROUND AND PURPOSE: The cerebellum has an influence on motor excitability. We investigated if the location of a cerebellar infarction was crucial for changes of motor cortex excitability and if the electrophysiological findings were correlated with motor performance. METHODS: Transcranial magnetic stimulation was applied to study intracortical inhibition (ICI), intracortical facilitation (ICF), motor thresholds, and corticospinal excitability. Dexterity as a measure of motor performance was tested with the Nine-Hole-Peg Test (9HPT). Ratios (affected/unaffected) were also calculated. RESULTS: ICI and ICF ratios were negatively correlated with 9HPT ratios in all patients (n=9). Compared with an age-matched control group, patients with lesions in the territory of the superior cerebellar artery (SCA) (n=3) or a lesion rostral of the dentate nucleus (n=1) had abnormally enhanced ICI and a loss of ICF (3 patients). Dexterity was impaired in all 4 patients. Motor excitability and motor performance normalized over the subsequent weeks. Patients with an infarct either in the territory of the anterior inferior cerebellar artery (n=2) or in the territory of the posterior inferior cerebellar artery (n=3) displayed motor excitability and motor performance within the normal range. CONCLUSIONS: The superior part of the cerebellum has a strong influence on motor cortex excitability. We suggest that the enhancement of motor inhibition and reduction of motor facilitation is mediated by an impairment of the deep cerebellar nuclei.

Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome. METHODS: From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization. RESULTS: Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis. CONCLUSIONS: Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.

Effect of intravenous thrombolysis on MRI parameters and functional outcome in acute stroke <6 hours.

BACKGROUND AND PURPOSE: The goals of this study were to examine MRI baseline characteristics of patients with acute ischemic stroke (AIS) and to study the influence of intravenous tissue plasminogen activator (tPA) on MR parameters and functional outcome using a multicenter approach. METHODS: In this open-label, nonrandomized study of AIS patients with suspected anterior circulation stroke, subjects received a multiparametric stroke MRI protocol (diffusion- and perfusion-weighted imaging and MR angiography) within 6 hours after symptom onset and on follow-up. Patients were treated either with tPA (thrombolysis group) or conservatively (no thrombolysis group). Functional outcome was assessed on day 90 (modified Rankin Score; mRS). RESULTS: We enrolled 139 AIS patients (no thrombolysis group, n=63; thrombolysis group, n=76). Patients treated with tPA were more severely affected (National Institutes of Health Stroke Scale score, 10 versus 13; P=0.002). Recanalization rates were higher in the thrombolysis group (Thrombolysis in Myocardial Infarction criteria 1 through 3 on day 1; 66.2% versus 32.7%; P<0.001). Proximal vessel occlusions resulted in larger infarct volumes and worse outcome (P=0.02). Thrombolysis was associated with a better outcome regardless of the time point of tPA treatment (< or =3 hours or 3 to 6 hours) (univariate analysis: mRS < or =2, P=0.017; mRS < or =1, P=0.023). Age (P=0.003), thrombolytic therapy at 0 to 6 hours (P=0.01), recanalization (P=0.016), lesion volume on day 7 (P=0.001), and initial National Institutes of Health Stroke Scale score (P=0.001) affected functional outcome (mRS on day 90) positively (multivariate analysis). The time point of tPA therapy affected the recanalization rate (P=0.024) but not final infarct volume. CONCLUSIONS: In this pilot study, tPA therapy had a beneficial effect on vessel recanalization and functional outcome. Multiparametric MRI delineates tissue at risk of infarction in AIS patients, which may be helpful for the selection of patients for tPA therapy. tPA therapy appeared safe and effective beyond a 3-hour time window. This study delivers the rationale for a randomized, MR-based tPA trial.

The predictive value of early CT and angiography for fatal hemispheric swelling in acute stroke.

PURPOSE: Our goal was to analyze the predictive value of early CT and arteriographic morphologic criteria to achieve a more reliable prediction of fatal outcome in patients undergoing fibrinolytic stroke treatment. METHODS: In 74 patients with acute carotid artery stroke, early signs of cerebral ischemia were determined by CT. The site of vascular occlusion was identified by digital subtraction angiography (DSA). The patients were subsequently treated by intraarterial (n = 68) or intravenous (n = 6) fibrinolysis by means of recombinant tissue plasminogen activator (rt-PA), urokinase, or rt-PA combined with lys-plasminogen and followed-up for a period of 3 months. CT and DSA data were compared with the clinical course, with special emphasis on signs of early fatal deterioration (ie, death by intracranial mass effect) as determined by corresponding CT and clinical observations, occurring within 7 days after stroke. RESULTS: Seventeen patients died, all of intracranial mass effect, and all within a week after stroke. In nine of these fatalities, DSA revealed carotid "T" occlusion (CTO), which affected 19 patients. In five of the fatalities, a major early sign of ischemia (MESI, referring to cortical hypodensity in more than a third of the territory of the middle cerebral artery, as seen in 14 patients) was recognizable on the initial CT scan. This led to a higher predictive value and sensitivity of CTO relative to MESI for estimating early fatality. CONCLUSION: CTO as determined by DSA is a substantially better predictor of fatal outcome in patients undergoing intraarterial thrombolytic therapy than is MESI as determined by CT.

[Stroke MRI: pathophysiology, potential and perspectives]. / Das Schlaganfall-MRT: Pathophysiologie, Potenzial und Perspektiven.

Magnetic resonance imaging (MRI) is increasingly utilized as the primary imaging modality in major stroke centers. The ability to depict several aspects of individual pathophysiology makes the use of MRI in stroke both attractive and complex. Profound knowledge of the pathophysiology of the imaging findings is crucial for a rational diagnostic workup. The pathophysiology of MRI in stroke will be reviewed considering recent experiences in clinical application, and the potential of stroke MRI will be assessed. Further perspectives like application of "blood oxygen level dependent" (BOLD) and the use of multiparametric prediction maps will be discussed.

[Spinal dural arteriovenous fistula: clinical and radiological findings in 54 patients]. / Die spinale durale arteriovenöse Fistelerkrankung (SDAVF): klinische und radiologische Befunde von 54 Patienten.

PURPOSE: Presentation of the clinical and radiological findings in spinal dural arteriovenous fistulas (SDAVF) based on the experience in 54 patients. MATERIAL AND METHODS: Evaluation of patients' records and myelography (n = 23), MRI (n = 54) as well as conventional angiography (n = 54) with respect to history, symptoms, clinical and radiological results. RESULTS: Clinically, a long history (mean 20 months) with progressive ascending paresis (100 %), sensory deficits (93 %) and loss of control over bladder and bowel function (89 %) in male patients (78 %) of advanced age (mean 60 years) indicates the disease. Typical signs in MRI are central cord hyperintensity (100 %) with slight medullary distension (74 %), contrast enhancement (79 %) and distended perimedullary veins (89 %), the latter being disclosed by myelography in 78 % of cases. For diagnosis spinal angiography is necessary which most often shows a thoracic location of the fistula (69 %), more than one feeding artery (67 %) and caudal as well as rostral venous drainage (63 %). CONCLUSION: MRI is superior to myelography to detect diagnostic signs of SDAVF in patients with typical clinical presentation. For definitive diagnosis spinal angiography is still indispensable.

[Endovascular therapy of high-degree stenoses of the neck vessels-stent-supported percutaneous angioplasty of the carotid artery without cerebral protection]. / Endovaskuläre Behandlung hochgradiger Halsgefässstenosen - Stentgestützte perkutane Angioplastie der Arteria Carotis ohne Protektion.

PURPOSE: Technical essentials and therapeutic results of carotid stenting without cerebral protection are presented. MATERIALS AND METHODS: In 161 patients, 167 high grade carotid stenoses were stented, followed by percutaneous transluminal angioplasty, with subsequent evaluation of the clinical and angiographic results. Diffusion-weighted MRI was carried out in 108 patients to detect cerebral sequelae. RESULTS: Endovascular therapy was successful (residual stenosis < 25 %) in 166 stenoses (99.4 %). Twelve patients (7.5 %) had cerebrovascular complications within the 30-day perioperative period, seven of which occurred during the procedure. After treatment, diffusion-weighted MRI disclosed at least one new cerebral lesion in 40 patients (37 %), which were symptomatic in six patients. CONCLUSION: Even without cerebral protection, high grade carotid stenosis can be safely treated with stent-protected percutaneous angioplasty. Microemboli detected by postoperative MRI are infrequently symptomatic.

Neue Aspekte zur Mechanik der Tuba auditiva.

The aim of the present article is to describe the mechanical components of the auditory tube and the role of these components in auditory tube function. Particular attention will be given to those aspects which have not been sufficiently dealt with in the past, such as the role of the isthmus region, the function of the lateral mucosal folds, the significance of the surfactant proteins and the pathophysiology of the patulous auditory tube. Special attention is given to the tensor veli palatini muscle and its physiology. Because of its isometric contraction, the function of this muscle depends on so-called hypomochlia changing the direction of its force. In the context of this article, the three hypomochlia involved are the pterygoid hamulus, Ostmann's fatty tissue and the medial pterygoid muscle.The so-called "Eppendorf-maneuver" is depicted for the first time.

A multicenter (1)H-MRS study of the medial temporal lobe in AD and MCI.

OBJECTIVE: The need for biological markers of Alzheimer disease (AD) is constantly increasing. Proton magnetic resonance spectroscopy ((1)H-MRS) studies have provided consistent evidence for a reduction of the neuronal marker N-acetylaspartate (NAA) in patients with AD. Within the German Competence Network on Dementia, we conducted a (1)H-MRS study in patients with mild dementia and mild cognitive impairment (MCI) at four sites to investigate the multicenter feasibility of (1)H-MRS. METHODS: In total, 130 patients with dementia (98 AD, 32 non-AD), 136 subjects with MCI (70 of AD type, 66 of non-AD type), and 45 unimpaired control subjects were included. Single-volume (1)H-MRS of the left medial temporal lobe was performed at long and short echo times. Metabolites were quantified and metabolic ratios were determined. RESULTS: We found a significant reduction of NAA concentration in patients with AD as compared to healthy volunteers and compared to patients with MCI of AD type. NAA/Cr (creatine/phosphocreatine) was also lower in patients with AD compared to control subjects. NAA, choline compounds, and Cr were lower in patients with AD compared to patients with non-AD dementia. CONCLUSIONS: We demonstrated the multicenter feasibility of proton magnetic resonance spectroscopy ((1)H-MRS) of the medial temporal lobe in mild dementia and mild cognitive impairment, which is a prerequisite for the application of (1)H-MRS in large-scale clinical trials. Since the concentration measures of the metabolites are adjusted for brain tissue volume, these findings are indicators of biochemical pathology beyond brain atrophy.

Influence of different ionic and pH environments on structural alterations of poliovirus and their possible relation to virus uncoating.

Poliovirus eclipse products were totally precipitated from infected HeLa cells after different times of infection by using TCA, suggesting that cellular enzymic digestion of parental proteins was not involved in virus uncoating. In an investigation of poliovirus thermal stability in vitro, progressive degradation of native virus into 80S empty capsids occurred upon incubation at 37 degrees C in a buffer of low ionic strength containing 20 mM-Tris-HCl pH 7.5, whereas in Eagle's medium or in the presence of L cells degradation was very slow. Degradation was faster at alkaline than at acid pH. Furthermore, liberation of the viral RNA was prevented and 135S particles were produced upon treatment of virus at 37 degrees C in 20-mM-Tris-HCl pH 7.5 containing 2 mM-CaCl2. Although the poliovirus receptor is able to induce conformational alterations of the capsid, low ion concentration could contribute to virus uncoating as well.

[Fibrinolytic therapy of acute cerebral infarct]. / Fibrinolysebehandlung beim akuten Hirninfarkt.

On the basis of our upon own results of local intra-arterial fibrinolysis (LIF), this article gives a short overview of recently established thrombolytic therapy in acute ischemic stroke. Fifty patients with acute occlusions of vertebrobasilar arteries and 118 patients showing occlusions of branches of the internal carotid artery were treated with LIF. The Occlusion type, occlusion site and successful recanalization were associated with a favorable outcome: 92% of embolic occlusions in the vertebrobasilar territory were recanalized and resulted in 50% in a favorable outcome. In the carotid territory, optimal outcome was achieved in main stem and branch occlusions of the middle cerebral artery, due to recanalization rates of 49%-64%. In contrast, occlusions of the intracranial bifurcation of the carotid artery (carotid-"T") resulted in death in 59%. Despite the lack of randomized trials, LIF is an established form of therapy in the vertebrobasilar territory. In the carotid territory randomized clinical studies could demonstrate the efficacy of intravenous fibrinolytic therapy in some stroke patients. It can be presumed from pilot studies that LIF is superior to the intravenous version in the carotid territory.

Intracranial tuberculomas mimicking a malignant disease in an immunocompetent patient.

We present the unusual occurrence of multiple systemic and two central nervous system tuberculomas in an immunocompetent young patient. A large left frontal epidural tuberculoma with transcalvarian extension was removed surgically and chemotherapy was initiated. The patient remained on a chemotherapy with INH, RMP, and EMB and was followed clinically and with MRI scans for 24 months. Findings. The clinical presentation and neuroimaging studies initially suggested malignant disease. Surgical resection of the left frontal lesion was required to relieve the mass effect. The histological evaluation showed a granulomatous inflammation with epithelial and Langhans giant cells, but no acid-fast bacilli. Cultures of the specimens yielded a mixed infection with Corynebacterium species and Staphylococcus epidermidis. Based on the histological findings, chemotherapy for tuberculosis was initiated. Subsequently, Mycobacterium tuberculosis was cultured from the surgical specimen and sputum. Interpretation. Parenchymal CNS tuberculosis with or without extracerebral manifestations may present as a space-occupying lesion. Because a tuberculoma is rarely suspected especially if there is atypical morphology, biopsy is required to establish the diagnosis and expedite specific treatment.

[New aspects of the mechanics of the auditory tube]. / Neue Aspekte zur Mechanik der Tuba auditiva.

The aim of the present article is to describe the mechanical components of the auditory tube and the role of these components in auditory tube function. Particular attention will be given to those aspects which have not been sufficiently dealt with in the past, such as the role of the isthmus region, the function of the lateral mucosal folds, the significance of the of the surfactant proteins and the pathophysiology of the patulous auditory tube. Special attention is given to the tensor veli palatini muscle and its physiology. Because of its isometric contraction, the function of this muscle depends on so-called hypomochlia changing the direction of its force. In the context of this article, the three hypomochlia involved are the pterygoid hamulus, Ostmann's fatty tissue and the medial pterygoid muscle. The so-called "Eppendorf-maneuver" is depicted for the first time.

Angiographic follow-up of vertebrobasilar artery aneurysms treated with detachable coils.

Endovascular treatment of ruptured vertebrobasilar artery aneurysms with Gugliemi detachable coils (GDC) has become an alternative to surgery. Mid-term angiographic follow-up can now be reported. Of 111 vertebrobasilar aneurysms in 110 patients we treated with GDC since 1992, 53 underwent angiography within 1 year and 59 after more than 18 months. We did not achieve complete occlusion on initial treatment of 23 aneurysms (21%). Complications were observed in 19 patients (17%), leading to permanent clinical disability in eight. Enlargement of the neck or reopening was seen in 12 (23%) of 53 aneurysms followed by angiography within 12 months. Documented recanalisation was treated in four (8%). Angiography was performed after 18-78 months in 59 patients, of whom nine, including three with initially incomplete occlusions, were retreated with GDC. Within the entire second observation period, three (5%) of the 59 patients had a further haemorrhage and were retreated with GDC. Rebleeding proved to be the only factor influencing the clinical outcome of retreated patients.

[Congestive myelopathy caused by spinal dural arteriovenous fistulas. Anamnesis, clinical aspects, diagnosis, therapy and prognosis]. / Die kongestive Myelopathie durch spinale durale arteriovenöse Fisteln. Anamnese, Klinik, Diagnostik, Therapie und Prognose.

Congestive myelopathy, formerly referred to as varicosis spinalis or Foix-Alajouanine syndrome, is caused by a spinal dural arteriovenous fistula (SDAVF). So far, the blood supply from the meningeal arteries draining through the fistula into the medullary venous system can only be verified by spinal angiography. Patients predominantly male and over the age of 60 are afflicted. Initially reversible functional disorders caused by the congestion of the spinal cord veins eventually become irreversible, the most common symptom being an increasingly paretic gait disorder, the signs of which generally begin symmetrically and progress from distal to proximal signs. Simultaneously, predominantly transverse sensory dysfunctions develop, as well as bladder and bowel dysfunctions, most often leading to incontinence. MRI typically shows a central medullary signal enhancement with slight swelling of the afflicted region, initially indicative of a reversible congestive edema and later of an irreversible infarction, and extended perimedullar vessels. Thus, if the clinical course and the characteristic MRI findings suggest the possibility of disease related to congestive myelopathy, spinal angiography becomes indispensable. Since ensuing the success of therapy and prognosis depends on rapid determination of the extent of the illness, a speedy diagnostic reaction is mandatory to institute the treatment necessary to prevent paraplegia.

[CT-angiography for diagnostic assessment of intracranial vascular aneurysms]. / Die CT-Angiographie zur diagnostischen Beurteilung intrakranieller Gefässaneurysmen.

Intracranial aneurysms bear a high risk of morbidity and mortality especially when they have become symptomatic due to rupture or represent a space occupying lesion. Therefore operative treatment is aimed at the obliteration of the aneurysm to eliminate the risk of hemorrhage. Planning of treatment requires a diagnostic resolution capable of showing aneurysms and their anatomic relationship to the adjacent structures. Due to technical advances computed tomography has reached a diagnostic accuracy sufficient to plan aneurysm treatment. This report describes the present state of three-dimensional spiral-CT angiography (3D-spiral-CTA) and our protocol to examine the arteries of the Circle of Willis for the presence and microanatomy of aneurysms. The experience of 46 patients with 64 aneurysms is reported and the diagnostic value of the method in comparison to conventional angiography is evaluated.