Long-Term Outcome of Patients with Spinal Dural Arteriovenous Fistula: The Dilemma of Delayed Diagnosis.

BACKGROUND AND PURPOSE: The impact of various radiologic and clinical features on the long-term outcome in spinal dural arteriovenous fistulas is still unclear; thus, they are the purpose of this study. MATERIALS AND METHODS: We retrospectively analyzed our medical data base for all patients treated for spinal dural arteriovenous fistula in our institution between 2006 and 2016. Patient age, neurologic status at the time of diagnosis, the duration of symptoms from onset to diagnosis, and follow-up information were evaluated. The extent of medullary T2WI hyperintensity, intramedullary contrast enhancement, and elongation of perimedullary veins on MR imaging at the time of diagnosis were additionally analyzed. RESULTS: Data for long-term outcome analysis were available in 40 patients with a mean follow-up of 52 months (median, 50.5 months; range, 3-159 months). The mean age at the time of diagnosis was 69.27 ± 9 years (median, 71 years; range, 53-84 years) with a male predominance (n = 32; 80%). The mean duration of symptoms was 20.2 months (median, 10 months; range, 1-120 months). Shorter duration of symptoms at the time of diagnosis was significantly correlated with better outcome of symptoms (P < .05). CONCLUSIONS: Spinal dural arteriovenous fistulas are characterized by interindividually variable clinical presentations, which make a determination of specific predictors for long-term outcome more difficult. Fast and sufficient diagnosis might result in a better outcome after treatment. The diagnosis of spinal dural arteriovenous fistula remains markedly delayed, reflecting an ongoing lack of knowledge and awareness among treating physicians of this rare-but-serious disease.

Treatment strategy and long-term outcome in patients with deep lumbosacral arteriovenous fistulas. A single center analysis in nineteen patients.

OBJECTIVE: Deep lumbosacral dural arteriovenous fistulas (lsDAVF) are rare and present serious diagnostic and treatment difficulties. In our current analysis we present our treatment strategy and the long-term clinical outcome of nineteen patients with lsDAVF. PATIENTS AND METHODS: We retrospectively analyzed our radiological and medical records for patients presenting with SDAVF between 1990 and 2018 at the University Hospital Aachen. We identified twenty patients with a lsDAVF. All patients were treated surgically. One patient died of pulmonary embolism three months after treatment and was excluded from our outcome analysis. Clinical data at time of admission, discharge, one year after discharge and at the last follow-up were evaluated according to modified Aminoff-Logue disability score (AL-score) for this analysis. RESULTS: Mean age was 65 ±â€¯7 years (median, 67; range, 53-78), sixteen patients (84 %) were male. After surgery, four patients developed a recurrent fistula in the same shunt zone and were re-treated microsurgically. Follow-up data one year after treatment was available in 15 patients. No relevant changes in AL-score were observed within this period. For the long-term follow-up analysis, data of 13 patients were available; 38.5 % of patients developed late functional deterioration. CONCLUSION: In our cohort, patients with deep lumbosacral dural arteriovenous fistula had a higher risk of early recurrence compared to patients with thoracolumbar SDAVF, with a considerable percentage of late functional deterioration. Thus strict clinical and radiologic long-term follow-up examinations are recommended in those patients.

Double spinal dural arteriovenous fistulas.

BACKGROUND: Spinal dural arteriovenous fistulas (SDAVF) are usually solitary lesions. Synchronous and/or metachronous double SDAVF have rarely been reported in the literature. We report on three patients with double SDAVF and present our single center experience in the diagnostic and treatment management in these patients. MATERIAL AND METHODS: We retrospectively revised our medical database for all patients who were diagnosed and treated in our center due to a SDAVF between 1990 and 2017. All data including demographics, clinical presentations, as well as radiological data were re-evaluated for this study. RESULTS: Three (1.4%) of 209 consecutive patients with SDAVF presented double SDAVF with different arterial feeders and venous drainage patterns. All three patients were men. The mean age at time of diagnosis was 67.9 ± 10 years (median; 68, range: 53-82). Myelopathic symptoms were reported in all three cases. All three fistulas were located in the thoracolumbar region between T7 and L2. MRI/CE-MRA showed medullar T2-hyperintensity, intramedullary contrast-enhancement and dilatation of perimedullary veins in various extensions. CONCLUSION: Double SDAVF are extremely rare and were found in 1.4% of patients in our series. The vast majority of the reported double SDAVF in the literature has been detected synchronously within an area of equal or less than three vertebral levels. Thus, whenever the SDAVF is identified, further injections of the fistula-zone neighbored segmental arteries might be recommended. However, due to the extremely low incidence of double SDAVF a complete spinal DSA is not indicated.

The clinical value of venous drainage in patients with spinal dural arteriovenous fistula.

BACKGROUND: Spinal dural arteriovenous fistulas (sdAVF) with rapid deterioration are a known clinical phenomenon but have been rarely reported in the past. Clinical and radiologic features of these fistulas are analyzed for this study. MATERIAL AND METHODS: We retrospectively reviewed our medical records for sdAVF patients who were treated in our center between 2006 and 2017. Our cohort was dichotomized in two groups; a) patients with acute/ subacute onset and rapid deterioration within a period of ≤6 months, b) patients with chronic progressive deterioration within a period of >6 months. MR findings at time of diagnosis were re-evaluated. All patients were treated microsurgically. Follow-up data were included. RESULTS: Data of forty patients were available for this study. Rapid deterioration was observed in 13/40 (32.5%) patients. AL-score at time of diagnosis did not differ between both groups (3.2 ±â€¯1.2 vs 3 ±â€¯2, p = .78). Patients with rapid deterioration showed significantly more prominent arterialized perimedullay veins at time of diagnosis (p < .05). At the last follow-up (53 ±â€¯3 months), patients with rapid deterioration improved up to one point on AL-scores (from 3.2 ±â€¯1.4 to 2 ±â€¯1.6) and those with chronic progressive deterioration were unchanged (from 3 ±â€¯1.6 to 3 ±â€¯1.7). CONCLUSION: Patients with rapid deterioration in our group (32.5%) presented with a significantly more prominent appearance of the arterialized perimeduallry veins. This may reflect, in the earlier phase of the disease, a better compensation of the venous hypertension as well as the associated venous outlet disorder of the spinal cord. This may also explain the better outcome of these patients.

Spinal Epidural Arteriovenous Fistula with Perimedullary Venous Reflux: Clinical and Neuroradiologic Features of an Underestimated Vascular Disorder.

BACKGROUND AND PURPOSE: The purpose of this study was to discuss the clinical and radiologic characteristics of spinal epidural arteriovenous fistulas (SEAVF) and demonstrate their specific angiomorphology in a single-center series. MATERIALS AND METHODS: Thirteen consecutive patients were diagnosed with SEAVF at RWTH Aachen University Hospital between 2006 and 2018 and were included in this study. All patients had MR imaging and DSA before treatment; 10 of these 13 patients received contrast-enhanced MRA (CE-MRA). RESULTS: The mean patient age was 72 ± 8 years. Paraparesis was present in 12 (92%) patients. Sphincter dysfunction and sensory symptoms were observed in 7 (54%) and 6 (46%) patients, respectively. The mean duration of symptoms was 6 ± 8 months. Congestive myelopathy on MR imaging was present in all patients. Prominent arterialized perimedullary veins were demonstrated in only 3 cases. CE-MRA revealed arterialized perimedullary veins and an arterialized epidural pouch in 9/10 (90%) patients, mostly located ventrolaterally. DSA demonstrated a multisegmental extension of the arterialized ventrolateral epidural pouch in 6 (46%) cases. An intradural radicular drainage vein was localized distant from the original fistula point in 3 (23%) patients. CONCLUSIONS: Congestive myelopathy with an acute/subacute clinical course was the dominant finding in spinal epidural arteriovenous fistulas. CE-MRA is a powerful diagnostic tool for identifying arterialized perimedullary veins as well as an arterialized epidural pouch. While arterialized perimedullary veins frequently present with only mild enlargement and elongation in spinal epidural arteriovenous fistulas, the arterialized epidural pouch is frequently located ventrolaterally and may extend over several vertebral levels. DSA remains the criterion standard to precisely visualize a spinal epidural arteriovenous fistula and its intradural radicular drainage vein, which may be located distant from the fistulous point.

Clinical and Radiologic Characteristics of Deep Lumbosacral Dural Arteriovenous Fistulas.

BACKGROUND AND PURPOSE: Spinal dural arteriovenous fistulas located in the deep lumbosacral region are rare and the most difficult to diagnose among spinal dural arteriovenous fistulas located elsewhere in the spinal dura. Specific clinical and radiologic features of these fistulas are still inadequately reported and are the subject of this study. MATERIALS AND METHODS: We retrospectively evaluated all data of patients with spinal dural arteriovenous fistulas treated and/or diagnosed in our institution between 1990 and 2017. Twenty patients with deep lumbosacral spinal dural arteriovenous fistulas were included in this study. RESULTS: The most common neurologic findings at the time of admission were paraparesis (85%), sphincter dysfunction (70%), and sensory disturbances (20%). Medullary T2 hyperintensity and contrast enhancement were present in most cases. The filum vein and/or lumbar veins were dilated in 19/20 (95%) patients. Time-resolved contrast-enhanced dynamic MRA indicated a spinal dural arteriovenous fistula at or below the L5 vertebral level in 7/8 (88%) patients who received time-resolved contrast-enhanced dynamic MRA before DSA. A bilateral arterial supply of the fistula was detected via DSA in 5 (25%) patients. CONCLUSIONS: Clinical symptoms caused by deep lumbosacral spinal dural arteriovenous fistulas are comparable with those of spinal dural arteriovenous fistulas at other locations. Medullary congestion in association with an enlargement of the filum vein or other lumbar radicular veins is a characteristic finding in these patients. Spinal time-resolved contrast-enhanced dynamic MRA facilitates the detection of the drainage vein and helps to localize deep lumbosacral-located fistulas with a high sensitivity before DSA. Definite detection of these fistulas remains challenging and requires sufficient visualization of the fistula-supplying arteries and draining veins by conventional spinal angiography.

The Transdural Course of Radicular Spinal Cord Veins--A Microangiographical and Microscopical Study.

PURPOSE: This study focuses on the following questions: What are the morphological features at the transdural course of radiculomedullary veins? How are these short transdural segments that may harbour pathological arteriovenous shunts connected to the internal vertebral venous plexus? Is the conception of a reflux-impeding mechanism at the transdural segment indispensable and convincing? METHODS: A total of 102 radiculospinal veins were studied microscopically at various levels of the spinal canal using serial paraffin and semi-thin sections. In addition, 26 vessels were investigated microangiographically following orthograde (12) or attempted retrograde (14) opacification of the intradural venous segment with barium sulphate. After paraplast-embedding, contact-microradiographs were taken using high-resolution spectroscopic plates. RESULTS: At their transdural course, the veins showed narrowing of their lumen accompanied by changes in the vessel wall composition and a tortuous course. Two structurally distinct arrangements of the transdural segment could be identified: A slit type was seen in 60% of the veins studied and a bulge- or nodular type was seen in 35% of the veins. In total, 5% of cases could not be assigned to either one of these types. Reflux to radicular veins from the outside of the dura mater could be produced in 2 out of 14 specimens. The extradural venous plexus, which primarily receives the radicular vein, was composed more frequently of lacunar spaces rather than plexiform blood vessel convolutions. Rare observations were fibrotic, blind ending radiculomedullary veins and continuation of a distinct venous blood vessel after crossing the dura. CONCLUSIONS: Reflux from the epidural plexus to radicular veins is not reliably stopped at the dural level and possibly physiological. Different arrangements of the transdural course of the veins appear to be at least appropriate to modulate flow. The purpose for two different types of radicular vein exit is unclear. The clinical impact of disturbed reflux-control is uncertain, which is in stark contrast to the severe consequences resulting from dural arteriovenous shunts. The functional role of the probably predominant epidural venous plexus for the spinal cord blood circulation remains poorly understood.

[The Compression Syndrome of Lumbar Arteries - Case Report of a Rare Disease Pattern]. / Das Kompressionssyndrom der Lumbalarterien - Kasuistik eines seltenen Krankheitsbilds.

STUDY DESIGN: We present a monocentric analysis of the lumbar artery compression syndrome (LACS) in the form of a case report. OBJECTIVES: Literature information was collected about the symptoms, diagnosis and treatment of this rare disorder in the context of the existing data. METHODS: The current medical literature includes only one report about three cases of LACS, collected over 20 years in France and Germany. We compared these cases with the experience of the European Vascular Center Aachen-Maastricht. RESULTS: The symptoms of this rare disorder are dominated by reversible, motion-dependent paralysis of the legs. Compression of the right lumbar arteries by muscular fibres or connective tissue is a fundamental cause. CONCLUSION: Surgical treatment, which means decompression of the lumbar arteries via a thoracolaparotomy, is an appropriate therapy with few complications and good long-term results.

Spinal cord motion: influence of respiration and cardiac cycle.

PURPOSE: To assess physiological spinal cord motion during the cardiac cycle compared with the influence of respiration based on magnetic resonance imaging (MRI) measurements. MATERIALS AND METHODS: Anterior-posterior spinal cord motion within the spinal canal was assessed in 16 healthy volunteers (median age, 25 years) by cardiac-triggered and cardiac-gated gradient echo pulse sequence MRI. Image acquisition was performed during breath-holding, normal breathing, and forced breathing. Normal spinal cord motion values were computed using descriptive statistics. Breathing-dependent differences were assessed using the Wilcoxon signed-rank test and compared with the cardiac-based cord motion. RESULTS: A normal value table was set up for the spinal cord motion of each vertebral cervico-thoracic-lumbar segment. Significant differences in cord motion were found between cardiac-based motion while breath-holding and the two breathing modalities (P < 0.01 each). Spinal cord motion was found to be highest during forced breathing, with a maximum in the lower cervical spinal segments (C5; mean, 2.1 mm ±â€Š1.17). Image acquisition during breath-holding revealed the lowest motion. CONCLUSION: MRI permits the demonstration and evaluation of cardiac and respiration-dependent spinal cord motion within the spinal canal from the cervical to lumbar segments. Breathing conditions have a considerably greater impact than cardiac activity on spinal cord motion. KEY POINTS: • Cardiac-triggered and ECG-gated MRI allows for demonstration of the smallest spinal cord motions.• Respiratory influences seem to have the highest impact on spine motion.• In contrast, the influence of the cardiac cycle seems to be small.• The smallest spinal cord motions were measured during breath-hold.

[Different manifestations of the cerebral nocardiosis]. / Unterschiedliche Manifestationsformen der zerebralen Nokardiose.

Nocardial infections affect mainly the respiratory tract but also can attack the CNS. Clinical experience with cerebral nocardiosis is very limited. We present two patients with very different cerebral affections due to nocardiosis. Cerebral nocardial infections can cause both multiple small abscesses and single large abscesses in the human brain. Despite the rare incidence of cerebral nocardiosis, it is an important differential diagnosis of expansive processes and abscesses in the CNS.

Value and limitations of contrast-enhanced MR angiography in spinal arteriovenous malformations and dural arteriovenous fistulas.

BACKGROUND AND PURPOSE: The purpose of this work was to study the validity of MR angiography (MRA) for identification of spinal arteriovenous (AV) abnormalities. MATERIALS AND METHODS: Thirty-four consecutive patients with suspicion of spinal vascular abnormalities underwent digital subtraction angiography (DSA) after MRA. The level and side of the suspected spinal dural arteriovenous fistula (SDAVF) and the feeding arteries in spinal arteriovenous malformations (SAVMs) were determined from the MRA and compared with DSA. RESULTS: DSA revealed SDAVF in 20 abnormalities of which 19 were spinal and 1 was tentorial with spinal drainage, as well as SAVM in 11 patients. In 3 patients, MRA and DSA were both normal. For detection of spinal arteriovenous abnormalities, neither false-positive nor false-negative MRA results were obtained. The MRA-derived level of the feeding artery in SDAVF agreed with DSA in 14 of 19 cases. In 5 cases, a mismatch of 1 vertebral level (not side) was noted for the feeding artery. For the tentorial AVF, only the spinal drainage was depicted; the feeding artery was outside the MRA field of view. In intradural SAVM, the main feeding artery was identified by MRA in 10 of 11 patients. MRA could differentiate between glomerular and fistulous SAVM in 4 of 6 cases and between sacral SDAVF and filum terminale SAVM in 2 of 5 cases. CONCLUSIONS: MRA reliably detects or excludes various types of spinal AV abnormalities and localizes the (predominant) arterial feeder of most spinal AV shunts. Although classification of the subtype of SAVMs remains difficult, with MRA it greatly helps to focus subsequent DSA.

Ischemic and hemorrhagic complications after intra-arterial fibrinolysis in vertebrobasilar occlusion.

BACKGROUND AND PURPOSE: To evaluate the incidence and location of hemorrhagic and ischemic lesions after local intra-arterial (IA) fibrinolysis in patients with acute vertebrobasilar occlusion (VBO). METHODS: One hundred forty-three patients with VBO treated with local IA fibrinolysis were retrospectively evaluated. Two different thrombolytic substances, namely urokinase (UK, n = 57 patients) and recombinant tissue plasminogen activator (rtPA, n = 86 patients), were used. Incidence and location of intracranial hemorrhage and ischemic infarction were assessed by means of 403 peri-interventional CT and MR imaging scans. Recanalization success and bleeding rate were correlated with the type and dosage of fibrinolytic agent. Multiple logistic regression was used for statistical analysis. RESULTS: Intracranial hemorrhage was detected in 46 (32%) patients. Bleeding rate was significantly higher for high-dose rtPA than for UK (36% versus 21%, P < .01). Neurologic outcome was worse in patients with postinterventional bleeding (P < .001). Ischemic infarctions were present in 136 (95%) patients. Ischemic lesions of the occipital lobe and thalamus were more frequently seen in the case of successful recanalization than after absent recanalization (P < .005). Occlusion of the postcommunicating segment of the posterior cerebral artery after successful recanalization was seen in 39% of patients. CONCLUSIONS: In acute VBO, bleeding rate after IA rtPA seems to be higher than that using IA UK, especially after high-dose rtPA. Ischemic lesion patterns after successful local IA fibrinolysis are common and correspond to the frequent distal migration of the thrombus. Novel recanalization techniques allowing for endovascular thrombectomy are needed to reduce ischemic and hemorrhagic complications in the treatment of acute VBO.

Outcome of acute vertebrobasilar occlusions treated with intra-arterial fibrinolysis in 180 patients.

BACKGROUND AND PURPOSE: To evaluate predictors of recanalization and a favorable neurologic outcome in patients with acute vertebrobasilar occlusion (VBO) treated with local intra-arterial fibrinolysis (LIF). METHODS: The multicentric data of 180 patients with acute VBO treated with LIF were retrospectively evaluated. The modified Rankin scale (mRS) was used to evaluate the neurologic status before LIF and at the time of discharge. Patient's sex, age, etiology of VBO, recanalization, symptom duration before LIF, and pretreatment mRS were correlated with posttreatment mRS. Multiple logistic regression analysis was used to identify independent variables for recanalization and neurologic outcome. RESULTS: The overall mortality was 43%. Complete recanalization was achieved in 99 (55%) patients and a partial recanalization in 35 (19%) patients, respectively. Recanalization was significantly associated with a favorable outcome (P < .001). The success of recanalization was negatively correlated with the volume of the thrombus (P < .001). No correlation was found between site and etiology of VBO and recanalization. Neurologic outcome correlated strongly with the pretreatment mRS (P < .001) and also with age (P < .02). Coma lasting less than 4.5 hours led to a positive trend toward a better outcome after univariate testing (P < .001). CONCLUSIONS: Success of recanalization and neurologic status before treatment predict neurologic outcome in patients with VBO. Thrombus volume has an adverse effect on the recanalization success.

MR angiography of the great anterior radiculomedullary artery (Adamkiewicz artery) validated by digital subtraction angiography.

BACKGROUND AND PURPOSE: Imaging of the anterior superficial spinal cord arteries by MR angiography is hindered by their small calibers and the similarity in configuration with the anterior superficial spinal cord veins. To validate the location and spatial configuration of the great anterior radiculomedullary artery, (ie, the Adamkiewicz artery [AKA]), contrast-enhanced MR angiography (CE-MRA) was compared with digital subtraction angiography (DSA). METHODS: Fifteen patients with suspected spinal cord vascular pathology underwent both spinal CE-MRA and selective spinal DSA. Two phase CE-MRA was performed with the use of a centric k-space filling scheme synchronized to the contrast bolus arrival. The level and side of the AKA origin were scored on the DSA and CE-MRA images and compared regarding image quality in terms of vessel conspicuity, contrast, continuity, sharpness, and background homogeneity on a relative 5-point scale. RESULTS: Localization and spatial configuration of the AKA by CE-MRA was in agreement with DSA findings in 14 of 15 cases. One mismatch of 1 vertebral level (not side) appeared as a result of the tangled vascular pathology. Comparison of image quality revealed that DSA is superior to CE-MRA concerning vessel continuity, sharpness, and background homogeneity (P < .001). Overall vessel conspicuity and contrast were judged to be similar. CONCLUSION: CE-MRA can visualize and localize the level of the AKA correctly. Image quality of CE-MRA is sufficient for detection of the AKA but is inferior to DSA.

Delayed diagnosis of spinal dural arteriovenous fistula in the absence of pathological vessels on MRI.

The authors report on a 69-year-old man presenting with progressive leg weakness and gait ataxia over two years. A central intramedullary cord lesion ranging from T8-12 on MR imaging was misdiagnosed as a low-grade glioma and a biopsy was attempted followed by temporary clinical deterioration. Selective spinal angiography revealed a spinal dural arteriovenous (AV) fistula on the left L3 nerve root sheath despite the absence of pathological vessels on MR imaging. The fistula was successfully treated by microsurgical interruption of the arterialized intradural vein. The present case should remind us to include selective spinal angiography in our diagnostic work-up in patients predisposed for spinal dural AV fistula by male sex, advanced age and clinical presentation of slowly progressive sensorimotor symptoms with myelopathy on MR imaging, even in the absence of any pathological vascular structures.

Silent microemboli related to diagnostic cerebral angiography: a matter of operator's experience and patient's disease.

INTRODUCTION: The aim of the present investigation was to elucidate in a large consecutive patient cohort whether the level of training has an effect on the number of microemboli detected by diffusion-weighted imaging (DWI) and which additional risk factors can be identified. METHODS: A total of 107 consecutive patients in whom a diagnostic cerebral angiography had been performed were prospectively investigated with DWI; 51 angiographies were performed by experienced neuroradiologists, 56 by neuroradiologists in training. RESULTS: In 12 patients (11.1%), a total of 17 new lesions without any clinically overt neurological symptoms were identified. Of these, 12 patients, 11 (91.7%) with 16 lesions were investigated by junior neuroradiologists. In 11 of 12 patients with DWI abnormalities (91.7%), risk factors could be identified (atherosclerotic vessel wall disease, vasculitis, hypercoagulable states). Experienced neuroradiologists performed 21 of 48 angiographies (43.8%) on patients with the above-mentioned risk factors, whereas junior neuroradiologists performed 27 angiographies in this subgroup (46.2%). The rate of diffusion abnormalities in patients with risk factors was 11/48 (22.9%) - considerably higher than in patients without risk factors (1/59; 1.7%). CONCLUSION: The level of experience and the nature of the underlying disease are predictors of the occurrence of cerebral ischemic events following neuroangiography. Alternative diagnostic modalities should be employed in patients who are investigated for diseases with the highest risk of angiographic complications (i.e., vasculitis, and arteriosclerotic vessel wall disease). If diagnostic angiography remains necessary in these patients, the highest level of practitioner training is necessary to ensure good patient outcome.

Non-traumatic cortical subarachnoid haemorrhage: diagnostic work-up and aetiological background.

Only 15% of all subarachnoid haemorrhages (SAHs) are not of aneurysmal origin. Among those, circumscribed SAHs along the cortical convexity are rare and have only been described in singular case reports so far. Here, we present a collection of 12 cases of SAH along the convexity, of non-traumatic origin. Over a period of 10 years, 12 cases of circumscribed SAH along the convexity were identified at our clinic. The clinical presentations, neuroradiological SAH characteristics, further diagnostic work-up to identify the underlying aetiologies, the therapy and clinical outcome were analysed. The patients' chief complaints were unspecific cephalgia, focal or generalised seizures and focal neurological deficits. Typical signs of basal SAH, such as nuchal rigidity, thunderclap-headache or alteration of consciousness, were rare. Magnetic resonance imaging (MRI) and digital subtraction angiography (DSA) revealed different aetiologies, namely postpartal posterior encephalopathy (three), cerebral vasculitis (two), dural sinus thrombosis (two), cortical venous thrombosis (one), intracerebral abscesses (one) and cerebral cavernoma (one). Two cases remained unresolved. Treatment of the underlying disease and symptomatic medication led to good clinical outcome in almost all cases. On the basis of these findings, we demonstrate that the clinical presentation, localisation and aetiology of cortical SAH differ clearly from other SAHs. A diagnostic work-up with MRI and eventually DSA is essential. Mostly, the causative disease can be identified, and specific treatment allows a favourable outcome.

Image-guided microneurosurgical management of small cerebral arteriovenous malformations: the value of navigated computed tomographic angiography.

In small arteriovenous malformations (AVM) with large hematomas, surgery remains the main therapeutic option. However, intraoperative identification of the AVM, feeders, and draining veins could be difficult in the environment of substantial intracerebral blood. In those selected cases, we use navigated computed tomographic angiography (CTA) for the microneurosurgical management. It is our objective to report our initial experiences. Prior to operation a conventional CTA with superficial skin fiducials placed on a patient's head was acquired for diagnostic and neuronavigation purposes. Image data were transferred to a neuronavigation device with integrated volume rendering capacities which allows a three-dimensional reconstruction of the vascular tree and the AVM to be created. In all patients the AVM was removed successfully after having been localized with CTA-based neuronavigation. Navigated CTA is helpful for the operative management of small AVMs with large hematomas. The technique allows feeding arteries to be distinguished from draining veins thereby allowing the nidus of the AVM to be identified despite the presence of substantial intracerebral blood. CTA can be easily implemented into commercial neuronavigation systems.