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Background Cranial dural arteriovenous fistulas (dAVFs) are rare lesions managed mainly with endovascular treatment (EVT) and/or surgery. We hypothesize that there may be subtypes of dAVFs responding better to a specific treatment modality in terms of successful obliteration and cessation of symptoms and/or risks. Methods All dAVFs treated during 2011–2018 at our hospital were analyzed retrospectively. Presenting symptoms, radiological variables, treatment modality, complications, and residual symptoms were related to dAVF type using the original Djindjian classification. Results We treated 112 dAVFs in 107 patients (71, 66% males). They presented with hemorrhage (n = 23; 21%), non-hemorrhagic symptoms (n = 75; 70%), or were discovered incidentally (n = 9; 8%). There were 25 (22%) type I, 29 (26%) type II, 26 (23%) type III, and 32 (29%) type IV fistulas. EVT was the primary treatment modality in 72/112 (64%) dAVFs whereas 40/112 (36%) underwent primary surgery with angiographic obliteration rates of 60% and 90%, respectively. Using a secondary treatment modality in 23 dAVFs, we obtained a final obliteration rate of 93%, including all type III/IV and 26/27 (96%) type II dAVFs. Except for headache, residual symptoms were rare and minor. Permanent neurological complications consisted of five cranial nerve deficits. Conclusions We recommend EVT as first treatment modality in types I, II, and in non-hemorrhagic type III/IV dAVFs. We recommend surgery as first treatment choice in acute hemorrhagic dAVFs and as secondary choice in type III/IV dAVFs not successfully occluded by EVT. Combining the two modalities provides obliteration in 9/10 dAVF cases at a low procedural risk.

Purpose Together with the foramen ovale, the middle meningeal artery (MMA) looks like a high heel shoe print on axial time-of-flight magnetic resonance angiography (TOF-MRA) images, with the MMA resembling the heel. Cranial dural arteriovenous fistulas (DAVF) are often fed by the MMA, which can lead to an increase of signal intensity and diameter of this vessel, resulting in a more “shiny” and “thick” high heel print appearance than on the contralateral side. We describe this finding as a novel radiologic sign and provide cut-off values for the ratios of MMA signal intensities and diameters for predicting the presence of a DAVF. Methods A total of 84 TOF-MRA examinations of 44 patients with DAVFs (40 with unilateral MMA feeders, 4 with bilateral feeders) and of 40 patients without DAVFs were included. Diameters and signal intensities of both MMAs were measured by two raters and evaluated using receiver operating characteristic analysis. Results The diameters of feeding and non-feeding MMAs differed significantly, as did the ratios of signal intensities and of diameters of DAVF and control patients (P Conclusion The described sign seems promising for the detection of DAVFs with noncontrast-enhanced MRI. The TOF-MRA source images should be reviewed with special attention to the MMA.

In brain arteriovenous malformations (BAVMs) and dural arteriovenous fistulas (DAVFs), when too much blood is drained into the venous system, extensive venous congestive encephalopathy (EVCE) can appear. EVCE in BAVMs and DAVFs can be divided into acute and chronic stages. BAVMs and DAVFs have their own classification systems, but EVCE is not considered in these classification systems and needs to be emphasized. EVCE in BAVMs and DAVFs has unique clinical and imaging features. The clinical presentations usually consist of headache, cognitive impairment, and focal deficits. EVCE in BAVMs and DAVFs has several imaging features, and the venous congestion seen on computed tomography angiography and magnetic resonance angiography can present with the angiographic features of venous reflux and pseudophlebitic pattern. Digital subtraction angiography is the gold standard for the diagnosis. Delayed circulation time is observed. Tortuous, dilated, and engorged veins can be seen. For EVCE from BAVMs and DAVFs, prompt treatment is warranted due to the impairment of extensive brain tissue. Treatments include endovascular treatment (EVT), open surgery, and radiosurgery. EVT is often the primary treatment. Complete elimination in one stage is often difficult. Most of the time, staged treatment has to be chosen. No matter at the acute or chronic stage, aggressive treatment is recommended.

Background and purpose A major challenge in spinal dural arteriovenous fistula (SDAVF) is timely diagnosis, but no specific predictive biomarkers are known. Methods In the discovery cohort (case, n = 8 vs. control, n = 8), we used cerebrospinal fluid (CSF) and paired plasma samples to identify differentially expressed proteins by label-free quantitative proteomics. Further bioinformatics enrichment analyses were performed to screen target proteins. Finally, it was validated by ELISA in two of the new cohorts (case, n = 17 vs. control, n = 9), and univariate analysis, simple linear regression, and receiver operator characteristic (ROC) curve analysis were performed to evaluate the diagnostic potential. Results In the discovery cohort, the most overexpressed proteins were APOB and C4BPA in CSF samples of patients. The GO/KEGG enrichment analysis indicated that the upregulated proteins were mainly involved in the acute inflammatory response and complement activation. Hub-gene analysis revealed that APP might be the key protein in the molecular interaction network. In the validation cohort, C4BPA and C1QA were significantly overexpressed in the CSF of patients, averaging 3046.9 ng/ml and 2167.2 ng/ml, respectively. Simple linear regression demonstrated that levels of C1QA and C4 were positively correlated with total protein in CSF (R2 = 0.8021, p = 0.0005; R2 = 0.7447, p = 0.0013). The areas under the ROC curves of C4BPA and C1QA were 0.86 and 1.00, respectively. Conclusions This study was the first to identify C4BPA and C1QA as potential biomarkers for the diagnosis of SDAVF and revealed that complement pathway activation might be one of the molecular mechanisms for venous hypertension myelopathy.

The functional changes concerning memory deficits in dural arteriovenous fistula (dAVF) brain are inadequately understood. This study aimed to understand the functional connectivity alterations of brain regions widely affirmed for explicit and implicit memory functions in dAVF patients (DP) and look into the frequency effects of the altered functional networks. Resting-state functional magnetic resonance imaging (rsfMRI) analysis was done in the memory-associated regions of 30 DP and 30 healthy controls (HC). Frequency decomposition was used to determine potential frequency-dependent functional connectivity changes. They underwent neuropsychological tests and were correlated with changes in memory networks compared with HC. The results showed weaker functional connectivity among the medial temporal lobe and sub-regions in DP suggestive of dysfunction of explicit and implicit memory functions, which corroborated with the positive correlation between memory scores and hippocampal–parahippocampal connectivity of DP, along with a significant group difference of lower memory and cognitive performance in DP assessed by neuropsychological tests. A frequency-dependent study of the altered rsFC revealed lower functional connectivity strength and impaired neural coupling manifested at some sub-band frequencies indicative of disturbed cortical rhythm in DP. This pilot study gives insights into significant intrinsic functional connectivity changes in the memory regions of the dAVF brain. The results may have clinical implications in the choice of interventional management of dAVF and can impact clinical decision making for realizable prevention of progressive memory impairment and irreversible brain damage in such patients.

Purpose Intracranial lateral dural arteriovenous fistula (LDAVF) represents a specific subtype of cerebrovascular fistulae, harboring a potentially life-threatening risk of brain hemorrhage. Fluoroscopically guided endovascular embolization is the therapeutic gold standard. We provide detailed dosimetry data to suggest novel diagnostic reference levels (DRL). Methods Retrospective single-center study of LDAVFs treated between January 2014 and December 2019. Regarding dosimetry, the dose area product (DAP) and fluoroscopy time were analyzed for the following variables: Cognard scale grade, endovascular technique, angiographic outcome, and digital subtraction angiography (DSA) protocol. Results A total of 70 patients (19 female, median age 65 years) were included. Total median values for DAP and fluoroscopy time were 325 Gy cm2 (25%/75% percentile: 245/414 Gy cm2) and 110 min (68/142min), respectively. Neither median DAP nor fluoroscopy time were significantly different when comparing low-grade with high-grade LDAVF (Cognard I + IIa versus IIb–V; p > 0.05, each). Transvenous coil embolization yielded the lowest dosimetry values, with significantly lower median values when compared to a combined transarterial/transvenous technique (DAP 290 Gy cm2 versus 388 Gy cm2, p = 0.031; fluoroscopy time 85 min versus 170 min, p = 0.016). A significant positive correlation was found between number of arterial feeders treated by liquid embolization and both DAP (rs = 0.367; p = 0.010) and fluoroscopy time (rs = 0.295; p = 0.040). Complete LDAVF occlusion was associated with transvenous coiling (p = 0.001). A low-dose DSA protocol yielded a 20% reduction of DAP (p = 0.021). Conclusion This LDAVF study suggests several local DRLs which varied substantially dependent on the endovascular technique and DSA protocol.

Our purpose is to present an atypical case of a 4-month-old patient with a giant dural arteriovenous fistula (DAVF). Presentation of a case report and review of the literature. The DAVF arterial supply was through the middle meningeal artery bilaterally and the anterior and middle cerebral arteries on the right hemisphere. The venous drainage was through the posterior two-thirds of the superior sagittal sinus. The endovascular team performed an embolization to reduce the flow of the lesion, and finally, the surgical team completed the excision of the residual venous sac, without causing any significant neurological deficit. We used a double surgical approach done with two surgical teams in order to optimize the hemostasis control and reduce morbidity and mortality. Midline DAVF usually has devastating consequences in children. Endovascular treatment is the first choice since it has lower mortality. Nevertheless, it requires multiple interventions, and the cure of the disease may not be achieved. We believe that joint endovascular and surgical treatment, supported by a reliable multidisciplinary medical team, is a good option for this type of lesions.

It is sometimes difficult to differentiate between high signals originating from a reverse flow on magnetic resonance angiography (MRA) and occult arteriovenous shunting. We attempted to determine whether arterial spin labeling (ASL) can be used to discriminate reversal of venous flow from arteriovenous shunting for high-signal venous sinuses on MR angiography. Two radiologists evaluated the signals of the venous sinus on MRA and ASL obtained from 364 cases without arteriovenous shunting. In addition, the findings on MRA were compared with those on ASL in an additional 13 patients who had dural arteriovenous fistula (DAVF). In the 364 cases (728 sides) without arteriovenous shunting, a high signal due to reverse flow in the cavernous sinuses (CS) was observed on 99 sides (13.6%) on MRA and none on ASL. Of these cases, a high signal in the sigmoid sinus, transverse sinus, and internal jugular vein was seen on 3, 3, and 8 sides, respectively. All of these venous sinuses showed a high signal from the reverse flow on MRA images. ASL is a simple and useful MR imaging sequence for differentiating between reversal of venous flow and CS DAVF. In the sigmoid and transverse sinus, ASL showed false-positives due to the reverse flow from the jugular vein, which may be a limitation of which radiologists should be aware.

Among neurointerventional procedures, the embolization of complex shunt lesions usually requires more radiation dose. We aimed to evaluate the procedural outcome and safety in using low-dose DSA protocols for intracranial dural arteriovenous fistula (AVF) embolization treatment. Between January 2014 and July 2018, 55 patients with dural AVFs who underwent endovascular treatment were included in the study. The low-dose group (n = 27) included from January 2016 used various low-dose DSA protocols made by modifying the thickness of the copper filter or the detector entrance dose. We compared radiation dose metrics, such as air-kerma, kerma-air product (KAP), and fluoroscopy time, as well as clinical and imaging outcomes with the conventional-dose group (n = 28) included before January 2016. The total KAP was 40.1% lower in the low-dose group (87.9 vs. 146.7 Gy cm2, p = 0.002). The average number of DSA runs (25.1 vs. 25.5, p = 0.86) and fluoroscopy times (77.4 vs. 69.7 min, p = 0.48) were similar between the groups. An immediate favorable occlusion rate (total or near total occlusion) was achieved in 41 (74.5%) patients. Ten patients (18.2%) underwent additional procedures due to residual (n = 6) and/or recurrent (n = 5) lesions. At a median of 10 months follow-up, 45 patients (86.5%) had achieved favorable occlusion. Treatment outcomes showed no significant between-group differences. There was one case (1.8%) of procedure-related complications in the low-dose group. All but one patient showed favorable clinical outcomes (modified Rankin score ≤ 2). The low-dose protocols were feasible by showing significant radiation dose reduction and acceptable procedural outcome.

Endovascular therapy to the spinal dural arteriovenous fistula (SDAVF) with a common origin of the radiculomedullary artery and the feeder of the shunt has the risk of spinal cord infarction. This study aimed to retrospectively assess the detection rate of normal spinal arteries from the feeder of SDAVF. We retrospectively collected the angiographic and clinical data of SDAVFs. This study included 19 patients with 20 SDAVF lesions admitted to our department between January 2007 and December 2018. We assessed the detection rate of normal radiculomedullary artery branched from the feeder of SDAVF between the period using the image intensifier (II) and flat panel detector (FPD) and evaluated the treatment results. The detection rates of the radiculomedullary artery branched from the feeder of SDAVF were 10% (1/10 lesions) during the II period and 30% (3/10 lesions) during the FPD period. During the FPD period, all normal radiculomedullary arteries branched from the feeder were only detected on slab maximum intensity projection (MIP) images of rotational angiography, and we could not detect them in 2D or 3D digital subtraction angiography. All lesions that had a common origin of a normal radiculomedullary artery and the feeder were completely obliterated without complications. There was no recurrence during the follow-up period. The flat panel detector and slab MIP images seem to show the common origin of the normal radiculomedullary arteries from the feeder more accurately. With detailed analyses, SDAVF can be safety treated.

Brain capillary telangiectasias (BCTs) are small, dilated capillary networks in the brain that are most commonly asymptomatic. Though rare, symptomatic cases of BCTs have been reported, and it is therefore important to understand the nature of these lesions in order to facilitate proper recognition. Relative to other intracranial vascular malformations, updated information on the various epidemiologic, radiographic, and pathologic features of BCTs within the published literature may be inadequate. We searched the PubMed database for prior reports of symptomatically-manifested BCTs. Moreover, Google Scholar and PubMed were searched in order to review current epidemiologic, radiographic, pathologic, and pathogenetic features of BCTs. Forty-eight published studies were included for a total of 99 individual cases of BCTs with symptomatic manifestations. Thirty-three symptomatic BCTs were hemorrhagic in nature, while 66 were non-hemorrhagic. The mean age at presentation of hemorrhagic lesions was 25.5 years, and the most common location was the supratentorial CNS (54.5%) with motor disturbance representing the most commonly encountered presenting symptom (26.1%). 15.2% of hemorrhagic lesions were treated with surgical removal. In non-hemorrhagic lesions, the mean age at presentation was 39.8 years with the pons being the most common lesion location (78.5%) and headache being the most common presenting symptom (22.2%). 12.1% of patients with non-hemorrhagic lesions were treated with surgical removal. Despite their rarity, symptomatic BCTs, both hemorrhagic and non-hemorrhagic, can cause devastating neurological sequelae, potentially through multiple mechanisms. The large majority of these lesions do not require intervention, though surgical removal has been achieved with good outcome in select cases. Further documentation of symptomatic manifestations with or without surgical intervention is vital in order to further understand the clinical, surgical, and pathogenic implications of these less-appreciated vascular malformations.

Meningioangiomatosis is a rare histologically distinct abnormality that is occasionally associated with intracranial meningioma. The rhabdoid variant of meningioma is also uncommon and is classified as a World Health Organization Grade III tumour. We report a case of meningioangiomatosis in conjunction with a meningioma with prominent rhabdoid features, in an infant male who underwent complete surgical resection of the lesion. The patient has been followed up for 6 years with no disease recurrence. To our knowledge, this is the first report in the literature describing meningioangiomatosis combined with a meningioma with rhabdoid features.

Background Spinal dural arteriovenous fistula (SDAVF) usually occurs during the 4th to 6th decades of life, and adolescent SDAVF is rarely reported. SDAVF arising around a tumor is also rare, and reported tumors are mostly schwannoma and lipoma. Case presentation We reported a 16-year-old male presented with progressive weakness and numbness of lower limbs for 3 months. A SDAVF was found, which was fed by right radicular arteries from segmental artery at L2 level and drained retrogradely into perimedullary veins. A concomitant spinal extradural nodular fasciitis at right L1/L2 intervertebral foramen was also noted. The SDAVF was completely obliterated by endovascular treatment and the tumor was debulked. The patient recovered well after the procedures. Conclusions Our case report suggests SDAVF can occur in adolescent. The concomitant presence with a nodular fasciitis indicates that although it usually arises in subcutaneous tissue but can rarely form on the dura of spine.

Background Spinal AVF (SAVF), a potentially treatable cause of myelopathy, remains a challenging diagnosis. Its rarity and non-specific imaging findings often result in misdiagnosis despite a high index of clinical suspicion. The classically described high T2 signal in the spinal cord or prominent vascular flow voids in the intradural space were not infrequently missed on initial imaging, only to be picked up at follow-up imaging after progression of symptoms. Additionally, small sized fistulas( Case presentation First was a 50-year-old man presented with spastic paraparesis and was found to have an AVF at the cervical region arising from the vertebral artery. Second, a 45-year-old man with acute paraplegia post-operatively, initially treated for a transverse myelitis before lumbar region AVF was detected. Thirdly, a 27-year-old man presented with subacute lower thoracic myelopathy and deteriorated after corticosteroid treatment. The last patient, who initially appeared to have conus medullaris/cauda equina syndrome had a SAVF at the mid thoracic level. Presentation varied with some exhibiting acute deterioration mimicking other spinal cord pathology such as inflammatory disorders. All patients eventually underwent endovascular treatment with successful embolization of SDAVF. None of them exhibited further neurological deterioration after embolization. Conclusion Successful treatment of SAVF is possible provided the diagnosis is made early, allowing timely intervention. Certain clues may aid the diagnosis. Firstly, arteriovenous fistula can be located distant to the clinical localization of myelopathy resulting in the unexpected longitudinally extensive spinal cord signal change. This clinical-radiological discrepancy can be a useful clue in diagnosing SAVF. Secondly, an acute myelopathic presentation immediately post-surgery may be related to SAVF. Other SAVF feature of note includes progressive myelopathy mimicking immune-mediated myelitis among young adults below 30 years of age refractory to immune therapy.

Background Approximately 10% of hereditary hemorrhagic telangiectasia (HHT) patients harbour brain vascular malformations (VMs). Intracranial hemorrhage (ICH) from brain VMs can lead to death or morbidity, while treatment options for brain VMs also have associated morbidity. The modified Rankin Scale (mRS) may provide an approach to identifying HHT-brain VM patients with poor outcomes, and their predictors. We aimed to measure the relationship between mRS score and brain VM, brain VM number, as well as other aspects of HHT, at enrollment and during prospective follow-up. Methods 1637 HHT patients (342 with brain VMs) were recruited from 14 HHT centres of the Brain Vascular Malformation Consortium since 2010 and followed prospectively (mean = 3.4 years). We tested whether the presence of brain VM, other HHT organ involvement, and HHT mutation genotype were associated with worse mRS scores at baseline and during follow-up, using linear mixed models, adjusting for age, sex, and year of visit. Results Presence of brain VMs was not associated with worse mRS score at baseline and there was no significant worsening of mRS with prospective follow-up in these patients; 92% had baseline mRS of 0–2. HHT-related gastrointestinal (GI) bleeding was associated with worse mRS scores at baseline (0.37, 95% CI 0.26–0.47, p p p Endoglin vs ACVRL1). Only GI bleeding was associated with a significantly worsening mRS during prospective follow-up (0.64, 95% CI 0.21–1.08, p = 0.004). Conclusion Most HHT-brain VM patients had good functional capacity (mRS scores 0–2) at baseline that did not change significantly over 3.4 mean years of follow-up, suggesting that mRS may not be useful for predicting or measuring outcomes in these patients. However, HHT patients with GI bleeding, anemia history or liver VMs had worse mRS scores, suggesting significant impact of these manifestations on functional capacity. Our study demonstrates the insensitivity of the mRS as an outcomes measure in HHT brain VM patients and reinforces the continued need to develop outcomes measures, and their predictors, in this group.

Arteriovenous malformations (AVMs) are typically congenital in origin, but acquired types, such as dural arteriovenous fistula (AVF), have been described. This study aimed to describe the diagnosis and endovascular treatment of acquired hepatic arterial–portal venous (HA-PV) malformations. A retrospective review of suspected acquired HA-PV malformations from 9/2011 to 2/2018 was performed. Eight patients (1M:7F, average age 62) with HA-PV malformations were identified. Four (50%) patients had a history of liver transplant. All HA-PV malformations were Yakes type IIIA (multiple inflow arteries with a single vein outflow and with the nidus located within the vein wall). In all cases, computed tomography angiography/magnetic resonance angiography was unable to distinguish AVMs from AVFs, and a wrong diagnosis was made in each instance. Review of pre-procedural Doppler ultrasounds in all cases demonstrated arterialization of portal vein waveforms. Review of pre-procedural cross-sectional (CT/MR) imaging in all of these cases demonstrates a network of arteries around the portal vein with early portal vein filling in every instance. Attempts to close the shunts via arterial inflow embolization but without venous nidus occlusion were performed and were unsuccessful in five out of eight (62.5%) cases. All curative therapies were via embolization of the outflow vein (segmental or lobar portal vein). Technical success was seen in seven of eight cases (87.5%), while one patient is planned to receive additional nidal vein embolization. Liver function was preserved after treatment without worsening of bilirubin or albumin levels. The diagnosis of an acquired HA-PV malformation can guide curative endovascular treatment by embolization of the portal vein outflow.

The aim of this study is to describe the clinical manifestations and treatment options of patients having dural sinus malformation with giant pouch (DSMGP) in a tertiary pediatric center. Dural sinus malformation with giant pouch (DSMGP) is a rare vascular malformation affecting fetuses, newborns, and infants. It is characterized by a dilated dural sinus frequently thrombosed with arteriovenous fistula (AVF) in its wall. There is a few information about symptoms, best treatment, and prognosis of the disease. Medical charts of cases of DSMGP were retrospectively analyzed from January 2010 to January 2019. Our hospital is a pediatric tertiary center. An adult patient managed by the authors in another institution was added to the series. Eight pediatric patients from 0 to 9 months were managed, four were males. The adult patient was a 40-year-old male. Symptoms were mass effect in 4 pediatric cases. Exophthalmos was present in the pediatric case and adult case. Both cases had venolymphatic malformation of the orbit. Congestive heart failure (CHF), epistaxis and facial vein engorgement, and intracranial hemorrhage (ICH) were the symptoms in other 3 cases. A child has spontaneous resolution of the disease. Transverse sinus and superior sagittal sinus are affected more commonly. Patients with totally thrombosed pouch had mass effect symptoms. These cases were managed by surgical excision. When AVFs are present, clinical manifestations were secondary to cerebral venous hypertension or cardiac overload. If cavernous sinus drained the shunt (capture), epistaxis and facial veins engorgement could be present. AVFs are amenable to embolization, achieving the control of venous hypertension in most cases. Cavernous malformation could be present and must be controlled because its enlargement could be a sign of uncontrolled venous hypertension. On the other hand, DSMGP can be accompanied by venolymphatic malformation conforming a cerebral venous metameric syndrome.

We herein present three cases of a rare type of spinal AVF, an intradural radicular AVF, which mimicked a dural AVF. A 65-year-old male presented with congestive myelopathy. On angiography, right vertebral angiogram (VAG) showed a suspected dural AVF; however, left VAG showed the same intradural dilated vein fed by the anterior spinal artery (ASA). Intraoperative and histological results suggested that a single AVF was located on the right C1 nerve root fed by the right C1 radicular artery and branch of the anterior spinal artery. Two additional patients with a radicular AVF at the C3 or C5 level were presented. Intradural radicular AVFs and dural AVFs have very similar appearances; however, there is a difference that makes the risk of the endovascular treatment of radicular AVFs markedly higher because of blood supply from the ASA. In our case, the AVF was completely occluded by direct surgery without major complications.

Craniofacial arteriovenous malformations (CF-AVMs) are locally aggressive extracranial lesions. When CF-AVMs involve cavernous sinus (CS) as their draining vein, they represent a special subgroup which may interfere intracranial venous system. In this study, we aimed to analyze the venous drainage patterns of CF-AVMs with CS drainage and to demonstrate how it affected our treatment strategy. Cases of CF-AVMs associated with CS drainage were collected from a prospectively collected database of patients with CF-AVMs who underwent endovascular treatment from September 2016 to March 2018. Clinical data and angioarchitectural findings were analyzed. Factors associated with the presence of venous reflux (cortical venous reflux (CVR) or dural sinus reflux (DSR)) were analyzed. Fifteen CF-AVM patients associated with CS drainage were analyzed. Three cases of venous reflux from the CS were identified (CVR, 2; DSR, 1). Lesions with unilateral venous drainage, ≤ 2 draining veins, and the absence of antegrade CS outflow were more likely to develop venous reflux from the CS. We successfully performed additional trans-venous coil embolization of the superior ophthalmic vein in two patients with malformations associated with venous reflux to close this venous connection to the CS. CF-AVMs associated with CS drainage confer an increased risk of CVR and DSR, especially in cases where the drainage outflow is restricted. Identification of this venous angioarchitecture is essential in the evaluation and treatment planning of CF-AVMs.

Cerebral capillary telangiectasia (CCT) is a type of vascular malformation that is incidentally encountered in clinical practice. Diseased vessels are small and usually clinically benign over the course of a patient's life. Although most CCT patients are asymptomatic, the situation becomes complicated when trauma is encountered. A case of sudden death due to an epileptic episode after very mild head trauma is reported, including a retrospective study of 12 cases, to remind peers to pay close attention to CCT especially when located in important functional regions of the brain. After immunohistochemical staining and pathological examination, we speculated that the epileptogenic mechanism of CCT may be similar to that of hippocampal sclerosis. As the definite epileptogenic mechanism of CCT in the hippocampus is still elusive, we suggest that more research should be conducted on CCT.

Background Dural arteriovenous fistulas are intracranial vascular malformations, fed by dural arteries and draining venous sinuses or meningeal veins. Clinical course varies widely and ranges from benign with spontaneous remission to fatal, due to cerebral hemorrhage. In a 10-year single institution experience, clinical presentation of dural arteriovenous fistulas, and in particular headache and angiographic features, as well as long-term outcome were analyzed. Methods Data of 42 intracranial dural arteriovenous fistulas of 40 patients concerning demographic characteristics, medical history and risk factors, clinical presentation and headache features, location and neuroimaging findings, as well as treatment and outcome, were collected. Furthermore, we used the modified-Rankin Scale to assess the long-term outcome, by telephone contact with patients and/or their relatives. Results Patients aged between 25 and 89 years (mean age 55.8 ± 15.5). According to different clinical presentation and evolution, related to their unique drainage pattern into the cavernous sinus, we examined the carotid-cavernous fistulas separately from other dural arteriovenous fistulas. Interestingly, we found that the migraine-like headache was the major onset symptom of dural arteriovenous fistulas different from carotid-cavernous fistulas (p = 0.036). On the other hand, non-migraine-like headache was a typical characteristic of carotid-cavernous fistulas (p = 0.003). Moreover, ocular symptoms were more frequently observed in carotid-cavernous fistulas (92.9% p < 0.001). Seventy percent of patients did not report any impact on quality of life (mRS 0 or 1) at follow-up. Conclusions These findings suggest a link between the site of lesion and clinical features of the headache, a symptom that usually leads to hospitalization. In particular, ocular symptoms accompanying non-migraine-like headache should be promptly recognized and raise the suspicion of a carotid-cavernous fistula, while migraine-like headache may suggests other dural arteriovenous fistulas. This study provides new significant insights on headache and its characteristics as a presentation symptom in dural arteriovenous fistulas.

The tentorial middle region (TMR) includes the midline and paramedian tentorium. TMR dural arteriovenous fistulae (DAVFs) are complex. We performed a review of the literature on TMR DAVFs. TMR DAVFs are divided into the following four types: incisural DAVF, Galenic DAVF, straight sinus DAVF and torcular DAVF. TMR DAVFs often drain into pial veins; therefore, most TMR DAVFs are classified as Borden II-III and Cognard types IIb-IV, whose characteristics cause TMR DAVFs to be prone to hemorrhage. TMR DAVFs have a very disappointing natural progression, and treatment is necessary. TMR DAVFs have extensive arterial supply and complex venous drainages, making them difficult to treat. Currently, for TMR DAVF, endovascular treatment (EVT) has become a better option. In EVT, transarterial embolization is the first-line treatment. Many complications can occur when treating TMR DAVFs, but complete EVT can generally achieve good clinical outcomes. In this review, three educational cases with demonstrating figures are provided to elaborate TMR DAVFs.

We report a novel case of a radiation-induced cavernous malformation developing in a vestibular schwannoma previously treated with stereotactic radiosurgery. Eleven years after treatment, the patient presented with a large predominantly cystic lesion in the cerebellopontine angle. We performed surgery, and a solid vascular lesion was identified within the schwannoma, which was determined to be a cavernous malformation after histopathological analysis. We review the literature of radiation-induced cavernous lesions, illustrating that while rare, these lesions do pose concern as a long-term complication of brain radiation therapy. We also discuss the possibility that radiation-induced cavernous malformation-like lesions are pathologically distinct from cavernous malformations.

The incidental diagnosis of both developmental venous anomalies (DVAs) and cavernous malformations (CMs) in the central nervous system is increasing with improved imaging techniques. While classically silent diseases, these cerebrovascular pathologies can follow an aggressive course, particularly when present in the brainstem. In the last decade, substantial research has focussed on KRIT1-mediated tight junction gene expression and their role in CM development. However, our understanding of the physiologic conditions precipitating symptomatic CM development or CM haemorrhage with and without concomitant DVAs, remains lacking. The only established risk factor for CM haemorrhage is a previous history of haemorrhage, and literature currently reports trauma as the only precipitant for symptomatic events. While plausible, this occurs in a minority, with many patients experiencing occult events. This manuscript presents a hypothesis for symptomatic CM events by first discussing the anatomical pathways for intracranial venous outflow via the internal jugular veins (IJV) and vertebral venous plexus (VVP), then exploring the role of venous flow diversion away from the IJVs under physiologic stress during dynamic postural shift. The resultant increase in intracranial venous pressure can exacerbate normal and pre-existing structural DVA pathologies, with repeated exposure causing symptomatic or CM-inducing events. This pathophysiological model is considered in the context of the role of the autonomic nervous system (ANS) in postural intracranial venous outflow diversion, and how this may increase the risk of DVA or CM events. It is hoped that this hypothesis invokes further investigation into precipitants for DVA or CM events and their sequela and, also, furthers the current knowledge on pathophysiological development of DVAs and CMs.

No data exist regarding retrieval of displaced or stretched coil extending to the right atrium after endovascular embolization of cerebrovascular diseases. We describe a snare technique for retrieval of a displaced coil extending to the right atrium after embolization of dural arteriovenous fistula (DAVF). A 35-year-old female with a DAVF underwent transjugular coil embolization that failed with displaced coil extending to the right atrium at an outside hospital. After admission to our hospital, Onyx embolization of the DAVF was performed through left facial vein–inner canthus vein–superior ophthalmic vein to the cavernous sinus. Post-embolization angiography showed complete occlusion of the DAVF. Then we attempted to snare the tip of the displaced coil that extended to the right atrium through femoral vein–inferior vena cava approach. However, current snare techniques failed to retrieve the extended coil after several attempts. Then one week later, we used a modified dual microcatheter and microwire technique to retrieve the displaced coil. One suite of microcatheter and microwire was used to produce a handmade snare device (HMD). The other suite of microcatheter and microwire was used to assist the HMD to snare the displaced coil. Through transjugular vein approach, we used our modified dual microcatheter and microwire snare technique (handmade snare device system) to retrieve the extended coil. After several attempts, the extended coil in the atrium was successfully retrieved. Post-procedure angiography and cardiac examinations did not show any signs of abnormality. For displaced coil extending to the right atrium after transvenous embolization, our method of modified dual microcatheter technique with HMD snare device system is an effective method to retrieve the extending coil.

Neurointerventional approaches have improved myelopathy in patients with spinal vascular lesions by providing effective management, particularly when surgical approaches are difficult. However, there have been challenges in describing and comparing recovery status during the post-treatment period. We evaluated 43 patients with venous congestive myelopathy (VCM) using Aminoff–Logue Disability Scale for gait (AL-G) and micturition (AL-M) scores. These results were compared with our new PSMS grading system that evaluates four categories (grades 0–3): pain, sensory symptoms, motor deficit, and sphincter change. Simple linear regression was used to identify the association or trend among the scales. We also calculated an overall area under the receiver operating characteristic curve to compare the predictive ability of the PSMS system with that of the previous grading system (AL-G and AL-M). Compared with other grading system, the PSMS system was more sensitively correlated with patient status and the results were easy to compare with previous clinical statuses during follow-up. The PSMS system also measured pain, which is commonly associated with spinal dural arteriovenous fistula and not precisely evaluated by other grading system. The new PSMS grading system for patients with VCM correlated well with the previously used systems and included pain evaluation. This new grading system is an easy tool for the evaluation and comparison of outcomes before and after endovascular treatment.

Our purpose was to investigate the added diagnostic value of C-arm contrast-enhanced cone-beam CT (CE-CBCT) to routine contrast-enhanced MRI (CE-MRI) in detecting associated developmental venous anomalies (DVAs) in patients with sporadic intracranial cavernous malformations (ICMs). Fifty-six patients (53 with single and three with double ICMs) met the inclusion criteria. All patients had routine CE-MRI scans performed at 1.5 Tesla. The imaging studies (CE-MRI and CE-CBCT) were retrospectively and independently reviewed by two observers, with consensus by a third. Group difference, intra- and interobserver agreement, and diagnostic performance of the modalities in detecting associated DVAs were calculated. Reference standard was CE-MRI. On CE-MRI and CE-CBCT, 37 (66%; of 56) and 47 patients (84%; of 56) had associated DVAs, respectively. In 10 patients (52.6%; of CE-MRI negatives [n=19]), CE-CBCT improved the diagnosis. Nine patients (16%; of 56) had no DVA on both imaging techniques. Difference in proportions of associated DVAs on CE-MRI and CE-CBCT was statistically significant, p

We have shown recently that damage to the right hemisphere impairs the ability to update mental models when evidence suggests an old model is no longer appropriate. We argue that this deficit is generic in the sense that it crosses multiple cognitive and perceptual domains. Here, we examined the nature of this updating impairment to determine more precisely the underlying mechanisms. We had right (RBD, N = 12) and left brain damaged (LBD, N = 10) patients perform versions of our picture-morphing task in which pictures gradually morph from one object (e.g., shark) to another (e.g., plane). Performance was contrasted against two groups of healthy older controls, one matched on age (HCO-age-matched, N = 9) and another matched on general level of cognitive ability (HCO-cognitively-matched, N = 9). We replicated our earlier findings showing that RBD patients took longer than LBD patients and HCOs to report seeing the second object in a sequence of morphing images. The groups did not differ when exposed to a morphing sequence a second time, or when responding to ambiguous images outside the morphing context. This indicates that RBD patients have little difficulty alternating between known representations or labeling ambiguous images. Instead, the difficulty lies in generating alternate hypotheses for ambiguous information. Lesion overlay analyses, although speculative given the sample size, are consistent with our fMRI work in healthy individuals in implicating the anterior insular cortex as critical for updating mental models.

Although involvement of the osseous component with an anterior condylar dural arteriovenous fistula (AC-DAVF) has been frequently described, osseous venous structures in which AC-DAVFs develop have not been fully elucidated. We investigated osseous venous structures adjacent to the hypoglossal canal in normal controls and patients with AC-DAVFs. The study included 50 individuals with unruptured aneurysms as normal controls and seven patients with AC-DAVFs. Osseous venous structures adjacent to the hypoglossal canal in normal controls were analyzed using computed tomography (CT) digital subtraction venography. In patients with AC-DAVFs, the fistulous pouches, draining veins, and surrounding venous structures were examined using cone beam CT. In 46.0% of laterals in normal controls, osseous venous structures were visualized within the jugular tubercle superomedially to the hypoglossal canal. We named these structures the jugular tubercle venous complex (JTVC). The JTVC was always continuous with the anterior condylar vein and was sometimes connected to surrounding venous channels. We detected nine fistulous pouches in the seven patients with AC-DAVFs. The fistulous pouches were in the JTVC (33.3%), anterior condylar vein (33.3%), and other venous channels within the exoccipital region (33.3%). Although the JTVC is a venous structure frequently found in normal people, it had not been investigated until now. The venous channel between the anterior condylar vein and JTVC is a common origin site for AC-DAVFs, and it was associated with 66.6% of the AC-DAVF cases in the current study.

Dural arteriovenous fistulas (DAVFs) are rare in pediatrics. A case of DAVF diagnosed because of a slight conjunctival hyperemia and endovascular coil embolization at 2 years old is reported. The 2-year-old boy presented with a slight conjunctival hyperemia of the left eye for 1 month. Magnetic resonance imaging (MRI) examination of the head showed abnormal blood flow in the left middle cranial fossa. On digital subtraction angiography, a DAVF with a dural feeder shunt and a venous varix at the middle cranial fossa was confirmed. After transarterial coil embolization, shunt blood flow disappeared. This report describes a case of DAVF with a slight conjunctival hyperemia treated by coil embolization in a child.

Type I and IIa dural arteriovenous fistulas (DAVFs) have a low hemorrhagic risk, but are often the cause of debilitating tinnitus that requires treatment. While Onyx® and PHIL™ (Precipitating hydrophobic injectable liquid) transarterial embolization represent the first endovascular option, there are occasional cases where performing angioplasty and stenting of the affected sinus may lead to satisfactory results. We retrospectively analyzed four consecutive cases of patients with DAVF-induced pulsatile tinnitus secondary to type I and II DAVFs who were treated with angioplasty and stenting of the sinus only. All the patients had clinical and radiological long-term follow-up. We noticed a significant radiological and clinical improvement in all the cases. Of the patients two were completely cured at follow-up with eradication of the neurological symptoms as well as the fistula, one was retreated with Onyx® for a very small residual shunt despite having no more tinnitus, and one showed improvement in venous drainage (from type IIa+b to type I fistula) without resolution of the fistula. In cases of type I and II DAVFs associated with sinus stenosis, angioplasty and stenting alone seem to be safe and effective. This treatment probably compresses the venules within the sinus walls, promoting thrombosis of the shunts thus solving the underlying cause of the fistula.

Cerebral arteriovenous malformations (AVMs) are rare vascular lesions potentially responsible for substantial neurological morbidity and mortality. Over the past four decades, radiosurgery has become a valid therapeutic option for many patients with small intracranial AVMs, but reports describing the use of robotic stereotactic radiosurgery (SRS) are rare. The purposes of this study are to describe the efficacy and toxicity of robotic SRS for AVMs and to review the literature. The reports of 48 consecutive patients treated with SRS were reviewed. A total dose of 18 Gy in a single fraction was prescribed to the 70% isodose line. Efficacy (i.e., total obliteration of the AVM) and toxicity were analyzed. Literature search was performed on Embase and PubMed for the terms “Radiosurgery and AVMs”, “Cyberknife and AVMs” and “Radiation therapy and AVMs.” The median follow-up was 41 months. The median AVM volume was 2.62 cm3. The incidence of obliteration was 59% at 3 years. Regarding toxicity, 92% of patients remained symptom-free, 66% developed radiogenic edema on MRI, and none developed radionecrosis. Forty-one patients (85%) had embolization prior to SRS. Our study was incorporated in an exhaustive review of 25 trials categorized by SRS technique. In this review, the median follow-up was 60 months. The median nidus volume was 2 cm3. The median overall obliteration rate for SRS was 68% (range 36 to 92). The median embolization rate prior to SRS was 31% (range 8.23 to 90). Compared to other studies, tolerability was excellent and the obliteration rate was acceptable but probably affected by the high embolization rate prior to radiosurgery. Our study suggests that a higher dose is feasible. A larger cohort with a longer follow-up period will be needed to confirm the safety and effectiveness, and subsequently validate different prognosis and predictive scores with this treatment modality to maximize the benefits of this technology for selected patients in the long term.

A spinal dural arteriovenous fistula (SDAVF) is an abnormal connection between a radiculomeningeal artery and a radiculomedullary vein (RMV) characteristically draining into the perimedullary venous system. We present an observation of SDAVF draining simultaneously into the perimedullary and epidural venous systems. A 67-year-old man presented with lower extremity weakness and sphincter dysfunction. MRI documented a longitudinally extensive myelopathy with parenchymal enhancement and flow-voids on T2-weighted images. Spinal angiography revealed the presence of two SDAVFs, at left T9 and right L1. The right L1 SDAVF was treated endovascularly. Superselective angiography of the main feeder, a right T12 radiculomeningeal branch, documented an unusual drainage pattern, with contrast flowing both retrogradely towards the perimedullary venous system and antegradely into the epidural plexus. The meningeal branch was embolized using a liquid embolic agent with adequate penetration of the embolic material into the proximal segment of the draining vein. The left T9 SDAVF was surgically resected, as the radicular artery supplying the fistula also provided the artery of Adamkiewicz. Dual drainage of the right L1 SDAVF into the perimedullary and epidural venous systems allowed to locate the site of the arteriovenous shunt at the point of transdural passage of the RMV, a narrowed segment also known to represent an anti-reflux mechanism. The potential role played by the topographical relationship between the shunt and the anti-reflux mechanism of the RMV in the formation and clinical expression of SDAVFs is discussed.

The long-term efficacy of endovascular treatment (EVT) for cavernous sinus dural arteriovenous fistulae (CS-dAVF) was assessed with a special focus on residual shunts after initial EVT. This retrospective survey included 50 patients who had undergone EVT and were followed for 1 month or longer (median follow-up 56 months). Common preoperative symptoms were chemosis (78%), extra-ocular motor palsy (72%), exophthalmos (66%), and tinnitus (26%). CS-dAVF were addressed by transvenous embolization (tVE, n = 48), tVE only was used in 43 instances and tVE plus transarterial embolization (tAE) in five. Two patients underwent tAE only. Procedure-related morbidity (brainstem infarction) was recorded in one patient (2%) and transient symptom exacerbation (paradoxical worsening) in 12 patients (24%). Postoperative digital subtraction angiography showed no major retrograde shunt or cortical venous reflux in any of the 50 patients. Anterograde or minor retrograde residual shunt was observed in 17 patients (34%); three of these underwent additional tVE and four had Gamma Knife surgery. The shunt flow disappeared in all 17 patients 12.6 ± 13.4 (mean ± SD) months after initial EVT. At the latest follow-up, 65.7 ± 52.6 months after the initial operation, no shunt flow was observed in any of the 50 patients. None had remaining or newly developed chemosis or tinnitus on follow-up. The rate of persistent cavernous sinus symptoms at the latest follow-up was higher in patients with than without post-procedural paradoxical worsening (5/12, 41.7% vs. 2/38, 5.3%, p = 0.0059 by Fisher’s exact test). Long-term follow-up showed that EVT, especially tVE, is an efficient and safe treatment for CS-dAVF. It resulted in the eventual disappearance of shunt flow. Residual shunt without major retrograde flow or cortical venous reflux can be monitored without additional treatment.

To evaluate spinal MRIs without and with 3D T2W imaging among patients without and with spinal dural arteriovenous fistula (SDAVF) confirmed by spinal digital subtraction angiography (DSA). A retrospective case-control study was performed among patients without and with SDAVF who had both spinal MRIs and gold standard spinal DSA. Two neuroradiologists independently reviewed spinal MRIs that were performed with either sagittal T2W turbo spin echo (2D group) or sagittal 3D T2W sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) (3D group) and documented the presence or absence of SDAVF. Using spinal DSA diagnosis as a gold standard, the sensitivity, specificity, and interobserver agreement for the 2D-group and 3D-group MRI diagnosis were calculated. The 2D group consisted of 21 patients and the 3D group consisted of 16 patients. For both radiologists, the 2D group demonstrated a sensitivity of 100% and specificity of 100%. Interobserver agreement in the 2D group was perfect (k = 1.0). For both radiologists, the 3D group demonstrated sensitivity of 100.0% and specificity of 92.3%. Interobserver agreement in the 3D group was perfect (k = 1.0). While flow voids were considered more conspicuous, spinal cord signal abnormality was considered less conspicuous with 3D T2W SPACE compared with conventional 2D STIR sequence. 3D T2W SPACE should be used in conjunction with 2D T2W sequences to more accurately detect abnormal cord signal and determine when perimedullary flow voids are pathologically abnormal for the radiologic diagnosis of SDAVF.

Developmental venous anomalies (DVA) are common neuroimaging abnormalities that are traditionally diagnosed by contrast-enhanced T1-weighted images as the gold standard. We aimed to evaluate the sensitivity of SWI in detecting DVA and associated cavernous malformations (CM) and microhemorrhages in children in order to determine if SWI may replace contrast-enhanced MRI sequences. Contrast-enhanced T1-weighted images were used as diagnostic gold standard for DVA. The presence of DVA was qualitatively assessed on axial SWI and T2-weighted images by an experienced pediatric neuroradiologist. In addition, the presence of CM and microhemorrhages was evaluated on SWI and contrast-enhanced T1-weighted images. Fifty-seven children with DVA (34 males, mean age at neuroimaging 11.2 years, range 1 month to 17.9 years) were included in this study. Forty-nine out of 57 DVA were identified on SWI (sensitivity of 86%) and 16 out of 57 DVA were detected on T2-weighted images (sensitivity of 28.1%). General anesthesia-related changes in brain hemodynamics and oxygenation were most likely responsible for the majority of SWI false negative. CM were detected in 12 patients on axial SWI, but only in six on contrast-enhanced T1-weighted images. Associated microhemorrhages could be identified in four patients on both axial SWI and contrast-enhanced T1-weighted images, although more numerous and conspicuous on SWI. SWI can identify DVA and associated cavernous malformations and microhemorrhages with high sensitivity, obviating the need for contrast-enhanced MRI sequences.

Sacral epidural arteriovenous fistulas (eAVFs) are rare and often misdiagnosed because of the incongruence between the thoracic level of clinical deficits and the sacral location of the offending pathology. Failure to diagnose this lesion delays treatment, resulting in prolonged venous hypertension in the cord, progressive neurological deterioration, and decreased chances of recovery. A single-institution case series and the published literature were reviewed. Three patients had sacral eAVFs are located in the ventral epidural space with outflow connections to radicular veins that arterialized spinal cord veins, all presenting with thoracic myelopathy, venous engorgement, and delayed diagnosis. All eAVFs were occluded completely with radiographic and clinical improvement. Sacral eAVF pathophysiology, namely venous hypertension and compromised spinal cord circulation, is exactly the same as dural AVFs, as is their treatment: the interruption of outflow by occlusion of the draining vein, which effectively eliminates venous hypertension, without occlusion of the actual fistula itself. Epidural exposure of sacral eAVFs is not necessary, whereas complete intradural occlusion of their radicular drainage is. Draining radicular veins intermingle with the nerve roots and their occasional multiplicity makes them more difficult to identify intraoperatively.

To assess the efficacy of stereotactic radiosurgery (SRS) for intracranial dural arteriovenous fistulas (DAVFs), the authors retrospectively reviewed our 7-year experience. We evaluated the obliteration rate, improvement in clinical symptoms, and complications. Thirty patients with DAVF underwent SRS using a Gamma Knife between 2009 and 2015. Twenty-three patients were treated with SRS alone, and seven patients underwent SRS for residual or recurrent DAVFs after embolization or surgery. Chemosis, diplopia, and pulsating tinnitus were the most common symptoms. Median target volume was 2.9 cm3 (range, 0.8–13.6 cm3), and median radiation dose to the target was 17 Gy (range, 12–20 Gy). Median follow-up period was 33 months (range, 6–82 months). At the last neuroimaging follow-up, DAVFs were totally obliterated in 23 patients (77%) and subtotally in 7 (23%). At the last clinical follow-up, 21 patients (70%) showed complete recovery, and 9 (30%) showed incomplete recovery in symptoms or signs. None experienced worsening symptoms or signs. Asymptomatic perilesional edema after SRS occurred in one patient (3%). Total obliteration rates after SRS were 43% at 1 year, 79% at 2 years, and 95% at 5 years. Improvement rates of neurological function after SRS were 12% at 1 month, 52% at 2 months, 72% at 3 months, and 96% at 6 months. A multivariate analysis revealed that Borden type 1 (p = 0.019, hazard ratio, 3.254, 95% confidence interval, 1.216–8.707) was significantly associated with symptom improvement. SRS for intracranial DAVFs provided a high obliteration rate and a relatively low risk of radiation-induced complications. In selected benign cases without cortical venous drainage, SRS is a safe and effective treatment for symptom relief and fistula obliteration, even though the time course of improvement is longer than those of embolization and surgery.

Spinal extradural arteriovenous fistulas (SEDAVF) with intradural drainage are uncommon vascular lesions that cause venous congestive myelopathy. We present three SEDAVF with intradural drainage treated with surgical disconnection of the intradural drainage via a single level laminectomy, followed by transarterial embolization (TAE) with Onyx if spontaneous thrombosis of the extradural fistula did not occur spontaneously. All patients improved their neurological condition and no congestive myelopathy recurrence was noted after mean follow-up of 84 months. We believe that SEDAVF with intradural drainage constitute a specific entity that should be included in the classifications of spinal arteriovenous malformations.

We report three cases in which carotid ultrasonography was useful for the diagnosis of dural arteriovenous fistula (dAVF). In all cases, dAVFs were fed by branches of the external carotid artery (ECA) and had retrograde leptomeningeal venous drainage. Carotid ultrasonography revealed high end-diastolic ratio (ED ratio) of the common carotid artery (CCA) (1.49-2.16) and low resistance index (RI) of the ECA (0.59-0.66). They were normalized after endovascular treatment (ED ratio of CCA 1.02-1.06, RI of ECA 0.75-0.87). In conclusion, high ED ratio of the CCA and low RI of the ECA might be a useful indicator for both screening and follow-up of dAVF.

Anterior cranial fossa dural arterio-venous fistulas (DAVFs) represent 6% of all intracranial DAVFs; characteristically they show an aggressive behaviour with high risk of intracranial haemorrhage. Peculiar anatomical features, such as feeding by the ethmoidal arteries and the pattern of venous drainage (frequently with varices that mimic aneurysmal dilatation), can be evaluated in detail only by digital subtraction angiography (DSA), which represents the “gold standard” in the diagnosis of such cranial fistulas. Recent technological developments in endovascular management of this type of DAVF have partially reduced the morbidity risk related to this modality of treatment. Our purpose is to present our experience in the surgical management of 14 patients with anterior cranial fossa DAVFs, with attention paid to the possible role of preoperative embolisation in these cases and to the surgical technique. Between 1999 and 2015, 14 patients with anterior cranial fossa DAVFs were submitted to surgery in two neurosurgical departments; the mean age was 63 years old; nine DAVFs caused intracranial haemorrhage (subarachnoid haemorrhage in three cases, intracerebral haemorrhage in six cases). Pre-operative embolisation was attempted in an early case and was successfully done in one recent case. In all patients, the surgical approach chosen was a pterional craniotomy with a low margin on the frontal bone in order to gain the exposure of the anterior cranial fossa and especially of the olphactory groove region; the resection of the falx at its insertion on the crista galli was needed in five cases in order to get access to the contralateral afferent vessels. Cauterisation of all the dural feeders on and around the lamina cribrosa was needed in all cases; venous dilatations were evident in eight patients (in seven out of nine patients with ruptured DAVF and in one out of five patients with unruptured DAVF) and were removed in all cases. One patient harboured an ophthalmic artery aneurysm, which was excluded by clipping. One patient died 5 days after surgery due to the severity of the pre-operative haemorrhage. Postoperative DSA showed the disappearance of the DAVF and of the venous pseudo-aneurysms in all cases. Clinical outcome was favourable (without neurological deficits) in 11 patients; three patients presented an unfavourable clinical outcome, due to the severity of the initial haemorrhage. Surgical exclusion of the anterior cranial fossa DAVFs still represents the gold standard for such lesions, due to low post-operative morbidity and to complete protection against future rebleedings; endovascular techniques may help the surgeon in complex cases.

Spinal arteriovenous malformations (SAVMs) are rare events. This study evaluated initial clinical presentations and treatment outcomes of SAVMs. In this study, 91 consecutive patients with SAVM between January 1993 and November 2014 were evaluated. Initial clinical presentations, radiological findings, treatment results, and follow-up outcomes were evaluated according to disease type and treatment modalities. Patient status was scored using the modified Rankin scale (mRS) and Aminoff–Logue Disability scale (ALS). Of the SAVM patients 69 % were male and 31 % were female with a mean age of 49 years (range 11–82 years). At the time of initial imaging evaluation, myelopathy was the most common finding with main complaints of gait disturbance (69 out of 91, 76 %), sensory disturbances (61/91, 67 %), and bowel or bladder symptoms (51/91, 56 %). Among the 80 patients who received treatment 56 (62 %) underwent endovascular embolization and 24 (26 %) underwent surgery. Complete obliteration was achieved in 47 patients (84 %) after endovascular embolization and in 18 (75 %) after surgical ligation. At the time of final follow-up 67 patients (84 %) showed improvement of more than 1 point on the mRS, while 69 (86 %) showed significant improvement on the ALS after treatment. The SAVMs presented with diverse neurological deficits, including myelopathy. Endovascular or surgical treatment of SAVMs can result in good clinical outcomes in most patients.

Unusual entrance of the vertebral artery into the cervical transverse foramen (UE-V2S) is a relatively common clinical anomaly. Because spinal surgeons should understand the anatomical characteristics and clinical implications of this condition, we aimed to provide a description based on a very large number of UE-V2S anomaly cases. We retrospectively analyzed 2207 three-dimensional head-and-neck computed tomographic angiograms (CTAs) that did not have specific vascular abnormalities. After confirming which cases had an unusual vertebral artery (VA) entrance into the transverse foreman (TF), we measured their vertebral artery diameter (VAD), transverse foramen area (TFA) and bilateral pedicle width (PW) from C3 to C7. The shortest horizontal distance from the vertical line in the medial margin of the TF to VA (D-TFVA) was measured in the extra-osseous region to estimate the exact location of the extra-osseous VA, except at the C7 level. An unusual V2 entrance was observed in 11.4 % (252 patients) of all 2207 consecutive patients and 6.5 % (268 courses) of all 4414 courses. The prevalence rankings for the different measures were as follows: unilateral UE-V2S = E5 > E4 > E7 > E3; bilateral UE-V2S = E5 (bilateral) > E4 (Rt) with E5 (Lt) > E4 (bilateral). Generally, the VAD of the anomaly side was statistically smaller than the normal contralateral side, which can induce a smaller TFA value at all sub-axial levels. Cervical pedicle fixation was preferable in the adjacent lower segment of unusual VA entrance level than the normal side in this study due to a broader PW, which was evident on the anomaly side. However, there was no statistical evidence that the side of the C7 entrance of the VA had a narrow PW. The lowest D-TFVA value was −3.8, indicating that we should take care not to exceed 3.8 mm medially into the vertical line of the medial TF wall during dissection when taking an anterior cervical approach. To avoid an unexpected VA injury and to improve the efficiency of even routine cervical operations, spinal surgeons should determine whether the patient has a UE-V2S and have a full understanding of the clinical characteristics of this anomaly.

Ethmoidal dural arteriovenous fistulae are rare vascular malformations associated with a high risk of bleeding. We present a multicenter contemporary series of patients treated with microsurgical and endovascular techniques. Sixteen consecutive patients were evaluated and/or treated between 2008 and 2015 at four centers with large experience in the endovascular and surgical treatment of cerebrovascular diseases. We analyzed demographic and clinical data, risk factors for dural fistulas, treatment type, peri- and post-operative morbidity, clinical and radiological outcomes, rates of occlusion, and long-term neurological outcome. Sixteen patients (81 % men, mean age of 58 years) with ethmoidal dural fistulas were included in the analysis. Seven patients had suffered an intracranial hemorrhage; the remaining presenting with neurological signs and symptoms or the fistula was an incidental finding. Three patients were managed conservatively. Among patients who underwent intervention (n = 13), 46.1 % were treated with endovascular therapy and 53.9 % were treated surgically. Complete angiographic obliteration was achieved in 100 % immediately after treatment and at last follow-up evaluation. All patients experienced a favorable neurological recovery (mRS 0-2) at the last follow-up visit (12 months). Ethmoidal dural AVFs are found mostly in male patients. Nowadays, due to wider use of non-invasive imaging, AVFs are discovered with increasing frequency in patients with minimal or no symptoms. Traditionally, these fistulas were considered "surgical." However, in the modern endovascular era, selected patients can be effectively and safely treated with embolization although surgical ligation continues to have an important role in their management.

Brain capillary telangiectasias (BCT) are small, clinically benign, usually asymptomatic and rarely seen lesions during childhood. Large symptomatic BCT during childhood are extremely rare, with only a few reports in the literature. They usually cannot be detected easily on conventional magnetic resonance imaging and angiography. We present the first pediatric case series of large pontine BCT presenting with distinct symptoms and in whom the lesions were detected by susceptibility-weighted imaging (SWI), for the first time to date. SWI provides a crucial imaging modality for BCT. We suggest that the combination of signal intensity loss on SWI and focal enhancement in a lesion otherwise not seen on conventional MR images is diagnostic for BCT and serves to discard serious differential diagnoses with high specificity, reassuring patients and referring physicians. We would like to emphasize clinical and radiological findings of BCT and utility of SWI images on MRI for the confirmation of diagnosis in the pediatric age group.

The current gold standard in the assessment of lateral intracranial dural arteriovenous fistulas (LDAVF) is digital subtraction angiography (DSA). However, magnetic resonance imaging (MRI) is a non-invasive emerging tool for the evaluation of such lesions. The aim of our study was to compare the DSA to our 3 T MR-imaging protocol including a highly spatial resolved (ce-MRA) and a temporal resolved (“time-resolved imaging of contrast kinetics”, TRICKS) contrast-enhanced MR angiography to evaluate if solely DSA can remain the gold-standard imaging modality for the treatment planning of LDAVF. We retrospectively reviewed matched pairs of DSA and 3 T MRI examinations of 24 patients with LDAVF (03/2008–04/2014) by the same list of relevant criteria for an endovascular LDAVF treatment planning. In particular, we determined intermodality agreement for the Cognard classification, the identifeication of arterial feeders, and the detailed assessment of each venous drainage pattern. Intermodality agreement for the Cognard classification was excellent (ĸ = 1.0). Whereas MRI failed in identifying small arterial feeders, it was superior to the DSA in the assessment of the sinus and the venous drainage pattern. The combination of MRI and DSA is the new gold standard in LDAVF treatment planning. • DSA is superior to the MRI in detecting LDAVF arterial feeders. • MRI excellently evaluates the venous side of an LDAVF. • MRI can replace DSA in initial diagnosis and monitoring of LDAVF. • MRI and DSA combined are the new gold standard in LDAVF treatment planning.