Cranial nerve deficits in giant cavernous carotid aneurysms and their relation to aneurysm morphology and location.

BACKGROUND: Giant cavernous carotid aneurysms (GCCAs) usually exert substantial mass effect on adjacent intracavernous cranial nerves. Since predictors of cranial nerve deficits (CNDs) in patients with GCCA are unknown, we designed a study to identify associations between CND and GCCA morphology and the location of mass effect. METHODS: This study was based on data from the prospective clinical and imaging databases of the Giant Intracranial Aneurysm Registry. We used magnetic resonance imaging and digital subtraction angiography to examine GCCA volume, presence of partial thrombosis (PT), GCCA origins, and the location of mass effect. We also documented whether CND was present. RESULTS: We included 36 GCCA in 34 patients, which had been entered into the registry by eight participating centers between January 2009 and March 2016. The prevalence of CND was 69.4%, with one CND in 41.7% and more than one in 27.5%. The prevalence of PT was 33.3%. The aneurysm origin was most frequently located at the anterior genu (52.8%). The prevalence of CND did not differ between aneurysm origins (p = 0.29). Intracavernous mass effect was lateral in 58.3%, mixed medial/lateral in 27.8%, and purely medial in 13.9%. CND occurred significantly more often in GCCA with lateral (81.0%) or mixed medial/lateral (70.0%) mass effect than in GCCA with medial mass effect (20.0%; p = 0.03). After adjusting our data for the effects of the location of mass effect, we found no association between the prevalence of CND and aneurysm volume (odds ratio (OR) 1.30 (0.98-1.71); p = 0.07), the occurrence of PT (OR 0.64 (0.07-5.73); p = 0.69), or patient age (OR 1.02 (95% CI 0.95-1.09); p = 0.59). CONCLUSIONS: Distinguishing between medial versus lateral location of mass effect may be more helpful than measuring aneurysm volumes or examining aneurysm thrombosis in understanding why some patients with GCCA present with CND while others do not. CLINICAL TRIAL REGISTRATION NO: NCT02066493 ( clinicaltrials.gov ).

Oxygen diffusion in marine-derived tissue engineering scaffolds.

This paper addresses the computation of the effective diffusivity in new bioactive glass (BG) based tissue engineering scaffolds. High diffusivities facilitate the supply of oxygen and nutrients to grown tissue as well as the rapid disposal of toxic waste products. The present study addresses required novel types of bone tissue engineering BG scaffolds that are derived from natural marine sponges. Using the foam replication method, the scaffold geometry is defined by the porous structure of Spongia Agaricina and Spongia Lamella. These sponges present the advantage of attaining scaffolds with higher mechanical properties (2-4 MPa) due to a decrease in porosity (68-76%). The effective diffusivities of these structures are compared with that of conventional scaffolds based on polyurethane (PU) foam templates, characterised by high porosity (>90%) and lower mechanical properties (>0.05 MPa). Both the spatial and directional variations of diffusivity are investigated. Furthermore, the effect of scaffold decomposition due to immersion in simulated body fluid (SBF) on the diffusivity is addressed. Scaffolds based on natural marine sponges are characterised by lower oxygen diffusivity due to their lower porosity compared with the PU replica foams, which should enable the best oxygen supply to newly formed bone according the numerical results. The oxygen diffusivity of these new BG scaffolds increases over time as a consequence of the degradation in SBF.

Factors affecting formation and rupture of intracranial saccular aneurysms.

Unruptured intracranial aneurysms represent a decisional challenge. Treatment risks have to be balanced against an unknown probability of rupture. A better understanding of the physiopathology is the basis for a better prediction of the natural history of an individual patient. Knowledge about the possible determining factors arises from a careful comparison between ruptured versus unruptured aneurysms and from the prospective observation and analysis of unbiased series with untreated, unruptured aneurysms. The key point is the correct identification of the determining variables for the fate of a specific aneurysm in a given individual. Thus, the increased knowledge of mechanisms of formation and eventual rupture of aneurysms should provide significant clues to the identification of rupture-prone aneurysms. Factors like structural vessel wall defects, local hemodynamic stress determined also by peculiar geometric configurations, and inflammation as trigger of a wall remodeling are crucial. In this sense the study of genetic modifiers of inflammatory responses together with the computational study of the vessel tree might contribute to identify aneurysms prone to rupture. The aim of this article is to underline the value of a unifying hypothesis that merges the role of geometry, with that of hemodynamics and of genetics as concerns vessel wall structure and inflammatory pathways.

Endovascular treatment of brain arteriovenous malformations using a liquid embolic agent: results of a prospective, multicentre study (BRAVO).

OBJECTIVES: To evaluate the safety and efficacy of a new liquid embolic agent in brain arteriovenous malformation (bAVMs) embolisation. METHODS: A prospective, multicentre series was conducted at 11 interventional centres in Europe to evaluate embolisation of bAVMs with the new liquid embolic agent. Technical conditions, complications, clinical outcome and anatomical results were independently analysed. RESULTS: From December 2005 to December 2008, 117 patients (72 male; 45 female, aged 18-75 years) were included. Clinical presentation was mostly haemorrhage (34.2 %) and seizures (28.2 %). Most AVMs were located in the brain hemispheres (85.5 %). AVMs were <3 cm in 52.1 % of patients and ≥ 3 cm in 47.9 %. Morbidity was observed in 6/117 patients (5.1 %), related to haemorrhagic events in 2 cases and non-haemorrhagic complications in 4 cases. Five patients (4.3 %) died in relation to the treatment (bleeding in 4 patients and extensive venous thrombosis in 1). Complete occlusion of the AVM by embolisation alone was obtained in 23.5 % of patients. Complementary treatment was performed in 82.3 % of patients with partial AVM occlusion, mostly radiosurgery. CONCLUSIONS: In this prospective, multicentre, European, observational series, the new liquid embolic agent proved to be suitable for BAVM embolisation, with acceptable morbidity and mortality and good efficacy. KEY POINTS: • Numerous interventional techniques have been used to embolise brain arteriovenous malformations (AVMs). • This prospective multicentre study demonstrates the suitability of a liquid embolic agent. • The safety of treatment using Onyx is acceptable. • Such embolisation leads to complete AVM occlusion in 23.5 % of patients.

The European Rare Disease Network for HHT Frameworks for management of hereditary haemorrhagic telangiectasia in general and speciality care.

Hereditary haemorrhagic telangiectasia (HHT) is a complex, multisystemic vascular dysplasia affecting approximately 85,000 European Citizens. In 2016, eight founding centres operating within 6 countries, set up a working group dedicated to HHT within what became the European Reference Network on Rare Multisystemic Vascular Diseases. By launch, combined experience exceeded 10,000 HHT patients, and Chairs representing 7 separate specialties provided a median of 24 years' experience in HHT. Integrated were expert patients who focused discussions on the patient experience. Following a 2016-2017 survey to capture priorities, and underpinned by more than 40 monthly meetings, and new data acquisitions, VASCERN HHT generated position statements that distinguish expert HHT care from non-expert HHT practice. Leadership was by specialists in the relevant sub-discipline(s), and 100% consensus was required amongst all clinicians before statements were published or disseminated. One major set of outputs targeted all healthcare professionals and their HHT patients, and include the new Orphanet definition; Do's and Don'ts for common situations; Outcome Measures suitable for all consultations; COVID-19; and anticoagulation. The second output set span aspects of vascular pathophysiology where greater understanding will assist organ-specific specialist clinicians to provide more informed care to HHT patients. These cover cerebral vascular malformations and screening; mucocutaneous telangiectasia and differential diagnosis; anti-angiogenic therapies; circulatory interplays between anaemia and arteriovenous malformations; and microbiological strategies to counteract loss of normal pulmonary capillary function. Overall, the integrated outputs, and documented current practices, provide frameworks for approaches that augment the health and safety of HHT patients in diverse health-care settings.

Use of Cangrelor in Cervical and Intracranial Stenting for the Treatment of Acute Ischemic Stroke: A "Real Life" Single-Center Experience.

BACKGROUND AND PURPOSE: In cases of large-vessel-occlusion strokes due to an underlying tandem internal carotid artery occlusion or intracranial atherosclerotic disease, concomitant stent placement may be needed. Immediate platelet inhibition is necessary, but to date, a standardized approach for antiplatelet inhibition in acute settings is still missing. Here we report our single-center experience about the safety and efficacy of periprocedural administration of cangrelor in patients with acute ischemic stroke due to intracranial or cervical artery occlusion undergoing stent placement. MATERIALS AND METHODS: We retrospectively evaluated all cases of acute ischemic stroke that needed acute stent implantation and were treated with periprocedural administration of cangrelor between January 2019 and April 2020 at our institution. All patients who needed either extracranial or intracranial artery stent placement (in either the anterior or posterior circulation) were included. RESULTS: We evaluated 38 patients in whom cangrelor was administered IV periprocedurally. Their mean age was 64 years (range, 26-85 years), with 25/38 male subjects and 13/38 female patients. In 26 patients (68.4%), a tandem occlusion was present and was treated with carotid artery stent placement, while 12 patients (31.6%) required an intracranial stent implantation. In 4 subjects (10.5%), an intracerebral hemorrhage occurred after the procedure. All patients in the series were alive 1 week after the procedure. CONCLUSIONS: Although larger, multicentric randomized studies are strongly warranted, our results support the hypothesis of a possible role of cangrelor as a valuable therapeutic option in the management of platelet inhibition in acute ischemic stroke procedures after intra- or extracranial stent placement.

Contrast echocardiography for pulmonary arteriovenous malformations screening: does any bubble matter?

AIMS: To evaluate diagnostic accuracy of contrast echocardiography (CE) as compared with CT, for the screening of pulmonary arteriovenous malformations (PAVMs) in hereditary haemorrhagic telangiectasia (HHT); to evaluate the clinical significance of semi-quantitative analysis of a shunt on CE. METHODS AND RESULTS: A blinded prospective study was conducted in 190 consecutive subjects at risk of HHT who underwent screening for PAVMs, including clinical evaluation, pulse oximetry, standard and CE, and chest multirow CT without contrast medium. A semi-quantitative analysis of the shunt size was performed according to the contrast echo opacification of the left-sided chambers: Grade 0, no bubbles; 1, occasional filling with <20 bubbles; 2, moderate filling; 3, complete opacification. The first 100 patients were compared with 100 controls. A total of 119 (63%) patients had positive CE (32.2% Grade 1, 13.1% Grade 2, 11% Grade 3, 6.3% with patent foramen ovale). The overall diagnostic performance of CE was sensitivity 1.00, specificity 0.49, positive predictive value (PPV) 0.32, negative predictive value (NPV) 1.00. The PPV for the different grades was 0.00 for Grade 1, 0.56 for Grade 2, 1.00 for Grade 3; the NPV of Grade 0 was 1.00. A significant correlation was found between the CE grading and the number of PAVM, and complications (P < 0.0001). CONCLUSION: CE is an extremely sensitive procedure for the detection of PAVMs with substantial clinical impact.

Angiographic follow-up of traumatic carotid cavernous fistulas treated with endovascular stent graft placement.

BACKGROUND AND PURPOSE: Endovascular treatment (EVT) of carotid cavernous fistulas (CCFs) is based on various techniques, mainly those using detachable balloons. Coronary covered stent grafts have been sporadically used in the intracranial arteries and only 2 traumatic CCFs have been reported in the literature; moreover, there is poor information about the long-term follow-up. We present 8 cases of CCFs treated by the placement of a covered stent, 5 of which have a 1-year clinical and angiographic follow-up. METHODS: Eight patients with posttraumatic CCF were treated by positioning a covered stent in the intracranial internal carotid artery (ICA) to occlude the fistula. They received periodic clinical and angiographic follow-up to evaluate the patency and the stability of clinical results. RESULTS: In all cases, the symptoms related to the CCF regressed after treatment and did not recur in the follow-up. Two patients presented residual filling of the CCF at the end of the procedure. The angiographic follow-up revealed in 6 patients of 7 a good patency of the ICA; in 1 patient, there was an ICA asymptomatic occlusion. One patient required transvenous coil occlusion of the cavernous sinus. CONCLUSION: When standard treatments fail, covered stent grafts can be used as a valid alternative in the treatment of CCFs, but more data are needed, especially in the long-term follow-up.

Bioactivity and Mechanical Stability of 45S5 Bioactive Glass Scaffolds Based on Natural Marine Sponges.

Bioactive glass (BG) based scaffolds (45S5 BG composition) were developed by the replica technique using natural marine sponges as sacrificial templates. The resulting scaffolds were characterized by superior mechanical properties (compression strength up to 4 MPa) compared to conventional BG scaffolds prepared using polyurethane (PU) packaging foam as a template. This result was ascribed to a reduction of the total scaffold porosity without affecting the pore interconnectivity (>99%). It was demonstrated that the reduction of total porosity did not affect the bioactivity of the BG-based scaffolds, tested by immersion of scaffolds in simulated body fluid (SBF). After 1 day of immersion in SBF, a homogeneous CaP deposit on the surface of the scaffolds was formed, which evolved over time into carbonate hydroxyapatite (HCA). Moreover, the enhanced mechanical properties of these scaffolds were constant over time in SBF; after an initial reduction of the maximum compressive strength upon 7 days of immersion in SBF (to 1.2 ± 0.2 MPa), the strength values remained almost constant and higher than those of BG-based scaffolds prepared using PU foam (<0.05 MPa). Preliminary cell culture tests with Saos-2 osteoblast cell line, namely direct and indirect tests, demonstrated that no toxic residues remained from the natural marine sponge templates and that cells were able to proliferate on the scaffold surfaces.

Risk Factors for Ischemic Complications following Pipeline Embolization Device Treatment of Intracranial Aneurysms: Results from the IntrePED Study.

BACKGROUND AND PURPOSE: Risk factors for acute ischemic stroke following flow-diverter treatment of intracranial aneurysms are poorly understood. Using the International Retrospective Study of Pipeline Embolization Device (IntrePED) registry, we studied demographic, aneurysm, and procedural characteristics associated with postoperative acute ischemic stroke following Pipeline Embolization Device (PED) treatment. MATERIALS AND METHODS: We identified patients in the IntrePED registry with post-PED-treatment acute ischemic stroke. The rate of postoperative acute ischemic stroke was determined by demographics, comorbidities, aneurysm characteristics, and procedure characteristics (including anticoagulation use, platelet testing, number of devices used, sheaths, and so forth). Categoric variables were compared with χ(2) testing, and continuous variables were compared with the Student t test. Odds ratios and 95% confidence intervals were obtained by using univariate logistic regression. Multivariate logistic regression analysis was used to determine which factors were independently associated with postoperative stroke. RESULTS: Of 793 patients with 906 aneurysms, 36 (4.5%) patients had acute ischemic stroke. Twenty-six (72.2%) strokes occurred within 30 days of treatment (median, 3.5 days; range, 0-397 days). Ten patients died, and the remaining 26 had major neurologic morbidity. Variables associated with higher odds of acute ischemic stroke on univariate analysis included male sex, hypertension, treatment of MCA aneurysms, treatment of fusiform aneurysms, treatment of giant aneurysms, and use of multiple PEDs. However, on multivariate analysis, the only one of these variables independently associated with stroke was treatment of fusiform aneurysms (OR, 2.74; 95% CI, 1.11-6.75; P = .03). Fusiform aneurysms that were associated with stroke were significantly larger than those not associated with stroke (mean, 24.5 ± 12.5 mm versus 13.6 ± 6.8 mm; P < .001). CONCLUSIONS: Ischemic stroke following PED treatment is an uncommon-but-devastating complication. Fusiform aneurysms were the only variable independently associated with postoperative stroke.

Pipeline Embolization Device with or without Adjunctive Coil Embolization: Analysis of Complications from the IntrePED Registry.

Flow diversion to treat cerebral aneurysms has revolutionized neurointerventional surgery. Because the addition of coils potentially increases the time and complexity of endovascular procedures, we sought to determine whether adjunctive coil use is associated with an increase in complications. Patients in the International Retrospective Study of Pipeline Embolization Device registry were divided into those treated with the Pipeline Embolization Device alone (n = 689 patients; n = 797 aneurysms; mean aneurysm size, 10.3 ± 7.6 mm) versus those treated with the Pipeline Embolization Device and concurrent coil embolization (n = 104 patients; n = 109 aneurysms; mean aneurysm size, 13.6 ± 7.8 mm). Patient demographics and aneurysm characteristics were examined. Rates of neurologic morbidity and mortality were compared between groups. The Pipeline Embolization Device with versus without coiling required a significantly longer procedure time (135.8 ± 63.9 versus 96.7 ± 46.2 min; P < .0001) and resulted in higher neurological morbidity (12.5% versus 7.8%; P = .13). These data suggest that either strategy represents an acceptable risk profile in the treatment of complex cerebral aneurysms and warrants further investigation.

Surpass flow diverter in the treatment of intracranial aneurysms: a prospective multicenter study.

BACKGROUND AND PURPOSE: Incomplete occlusion and recanalization of large and wide-neck brain aneurysms treated by endovascular therapy remains a challenge. We present preliminary clinical and angiographic results of an experimentally optimized Surpass flow diverter for treatment of intracranial aneurysms in a prospective, multicenter, nonrandomized, single-arm study. MATERIALS AND METHODS: At 24 centers, 165 patients with 190 intracranial aneurysms of the anterior and posterior circulations were enrolled. The primary efficacy end point was the percentage of intracranial aneurysms with 100% occlusion on 6-month DSA. The primary safety end point was neurologic death and any stroke through a minimum follow-up of 6 months. RESULTS: Successful flow-diverter delivery was achieved in 161 patients with 186 aneurysms (98%); the mean number of devices used per aneurysm was 1.05. Clinical follow-up (median, 6 months) of 150 patients (93.2%), showed that the primary safety end point occurred in 18 subjects. Permanent neurologic morbidity and mortality were 6% and 2.7%, respectively. Morbidity occurred in 4% and 7.4% of patients treated for aneurysms of the anterior and posterior circulation, respectively. Neurologic death during follow-up was observed in 1.6% and 7.4% of patients with treated intracranial aneurysms of the anterior and posterior circulation, respectively. Ischemic stroke at ≤30 days, SAH at ≤7 days, and intraparenchymal hemorrhage at ≤7 days were encountered in 3.7%, 2.5%, and 2.5% of subjects, respectively. No disabling ischemic strokes at >30 days or SAH at >7 days occurred. New or worsening cranial nerve deficit was observed in 2.7%. Follow-up angiography available in 158 (86.8%) intracranial aneurysms showed 100% occlusion in 75%. CONCLUSIONS: Clinical outcomes of the Surpass flow diverter in the treatment of intracranial aneurysms show a safety profile that is comparable with that of stent-assisted coil embolization. Angiographic results showed a high rate of intracranial aneurysm occlusion.

International retrospective study of the pipeline embolization device: a multicenter aneurysm treatment study.

BACKGROUND AND PURPOSE: Flow diverters are increasingly used in the endovascular treatment of intracranial aneurysms. Our aim was to determine neurologic complication rates following Pipeline Embolization Device placement for intracranial aneurysm treatment in a real-world setting. MATERIALS AND METHODS: We retrospectively evaluated all patients with intracranial aneurysms treated with the Pipeline Embolization Device between July 2008 and February 2013 in 17 centers worldwide. We defined 4 subgroups: internal carotid artery aneurysms of ≥10 mm, ICA aneurysms of <10 mm, other anterior circulation aneurysms, and posterior circulation aneurysms. Neurologic complications included spontaneous rupture, intracranial hemorrhage, ischemic stroke, permanent cranial neuropathy, and mortality. Comparisons were made with t tests or ANOVAs for continuous variables and the Pearson χ(2) or Fisher exact test for categoric variables. RESULTS: In total, 793 patients with 906 aneurysms were included. The neurologic morbidity and mortality rate was 8.4% (67/793), highest in the posterior circulation group (16.4%, 9/55) and lowest in the ICA <10-mm group (4.8%, 14/294) (P = .01). The spontaneous rupture rate was 0.6% (5/793). The intracranial hemorrhage rate was 2.4% (19/793). Ischemic stroke rates were 4.7% (37/793), highest in patients with posterior circulation aneurysms (7.3%, 4/55) and lowest in the ICA <10-mm group (2.7%, 8/294) (P = .16). Neurologic mortality was 3.8% (30/793), highest in the posterior circulation group (10.9%, 6/55) and lowest in the anterior circulation ICA <10-mm group (1.4%, 4/294) (P < .01). CONCLUSIONS: Aneurysm treatment with the Pipeline Embolization Device is associated with the lowest complication rates when used to treat small ICA aneurysms. Procedure-related morbidity and mortality are higher in the treatment of posterior circulation and giant aneurysms.

Prognostic significance of hyperglycemia in acute stroke.

Prognostic significance of hyperglycemia on short-term survival was evaluated in 72 patients with acute hemispheric stroke. All patients were admitted within 48 hours of onset, and the neurologic deficit was assessed by means of a standardized score. A computed tomogram was taken in all cases on admission. Mortality was higher in hyperglycemic patients with no history of diabetes mellitus (78%) than in diabetic (45%) and in normoglycemic nondiabetic (29%) patients. In nondiabetic patients, the glucose level correlated with the neurologic score and with lesion size on computed tomogram. Reactive hyperglycemia due to a major stress response accounts for the worse prognosis of these patients. This correlation was not found in diabetic patients. Preexisting hyperglycemia, as well as systemic complications, could explain the higher mortality in these patients compared with normoglycemic nondiabetic patients.

Venous thromboembolism in acute stroke. Prognostic importance of hypercoagulability.

To assess the incidence, risk factors, and clinical importance of deep vein thrombosis in acute stroke, we studied 70 consecutive patients who underwent hemostasis screening at the time of entry into the study and followed up these patients with serial venous Doppler examinations and the iodine 125-labeled fibrinogen uptake test. Mortality was significantly higher among the 20 patients who developed a deep vein thrombosis, and eight of them had necropsy evidence of pulmonary embolism. Severity of leg paresis and a shortened activated partial thromboplastin time were significantly associated with subsequent deep vein thrombosis with multivariate analysis. Significantly higher levels of fibrinopeptide A were found in patients with postmortem evidence of pulmonary embolism. Deep vein thrombosis is a frequent complication of acute stroke and may influence the prognosis by inducing pulmonary embolism. Our findings allow rapid identification of high-risk patients who may benefit maximally from prophylactic treatment of venous thromboembolism.

Hypercoagulability in acute stroke: prognostic significance.

To evaluate the clinical significance of hemostatic abnormalities in acute stroke, we studied coagulation and platelet function in 70 patients with recent cerebral infarction or hemorrhage and in 45 age-matched controls. Higher levels of one-stage factor VIII coagulant activity, fibrinopeptide A (FPA), and beta-thromboglobulin were associated with the occurrence of stroke. All hemostatic test results were remarkably similar in patients with ischemic and hemorrhagic stroke. FPA levels and size of the lesion on CT were the only variables independently predicting mortality in a multivariate regression analysis. Our findings demonstrate that hypercoagulability is an important prognostic factor in stroke and lend support to clinical trials of drugs interfering with the coagulation system in the early phase of cerebral ischemia.

Alexia in recent and late Broca's aphasia.

The hypothesis was tested that alexia associated with Broca's aphasia may often be a residual receptive disorder of a broader picture of global aphasia. It was found that alexia does tend to be associated, as expected, to the long-standing Broca's aphasias more often than to the recent ones. However, the CT scan failed to disclose larger and more posterior lesions in Broca's alexic than in Broca's non-alexic patients.

Myelopathy and radiculopathy due to cervical spondylosis: myelographic-CT correlations.

Forty patients with symptoms and signs of radicular disease or spinal cord involvement secondary to cervical spondylosis were studied with myelography (using nonionic water-soluble contrast medium) followed by computed tomographic (CT) myelography. In 17 patients CT was also performed before myelography. CT myelography adds useful information to the myelographic findings. Cord compression is better evaluated and osteophytes can be differentiated from disk herniation. Plain CT can demonstrate a herniated disk but with less accuracy than CT myelography. Cord and root compression are not seen directly on plain CT; for this reason myelography should be the first procedure in patients with myelopathy or myeloradiculopathy, which may be followed by CT myelography.

Unexpected CT-scan findings in global aphasia.

The clinical-CT scan correlation was studied in 37 stroke patients with global aphasia. The time between stroke and language examination was between 21 and 60 days; the time between stroke and CT scan was equal to or longer than 21 days. It was found that while 22 patients harboured the expected large lesions including Broca's and Wernicke's areas, 8 had anterior lesions sparing Wernicke's area, 3 had posterior lesions sparing Broca's area, and 4 had deep lesions centered on the insula and lenticular nucleus. These findings suggest that global aphasia, albeit apparently simple from the semeiological viewpoint (also due to its severity), does in fact include different clinical entities. However, no clear-cut correlation was found between either subtype of speech production or severity, and locus of the lesion (except that deep lesions were associated with somewhat milder forms). An interesting finding, i.e. that all 8 patients with anterior lesions were females, while the 3 posterior ones were male, is briefly discussed in terms of possible differential organization of language functions in the two sexes.

Progressive myelopathy caused by intracranial dural arteriovenous fistula: report of two cases and review of the literature.

We report two rare cases of progressive myelopathy caused by intracranial dural arteriovenous fistulae with venous drainage into the spinal medullary veins. Both patients were referred to us with a history of progressively worsening quadriparesis. A posterior fossa dural arteriovenous fistula with spinal venous drainage was discovered by angiography in both cases. Treatment consisted of direct clipping of the venous drainage in one patient and of transarterial embolization and excision of the involved dural sinus in the other patient. Such procedures provided a radioanatomical cure and marked neurological recovery in both patients. Only 10 cases of progressive myelopathy caused by an intracranial dural arteriovenous fistula have been previously reported. Dysfunction of the cervical cord by venous engorgement is thought to be the most probable cause of the neurological symptoms in such cases.