[Consideration of the Mechanism for Anterior Condylar Confluent Dural AVF Diagnosed with Neck Pain]

OBJECTIVE

Anterior condylar confluent dural arteriovenous fistula(ACC-dAVF)constitutes 3.7% of the total dAVF cases reported and has been regarded as a rare disease in the past. However, encounters with this disease are increasing due to MRI and awareness of this condition. The symptoms of this disease have been reported as tinnitus(75%), ocular symptoms(31%), sublingual nerve palsy(12%), spinal cord symptoms(11%), and intracranial bleeding(5%). Here, we report our identification of a case of ACC-dAVF, which is different from conventional reports, and the associated findings.

CASE PRESENTATIONS

We experienced a series of 3 cases of ACC-dAVF with the chief complaint of neck pain. The symptoms in all three patients disappeared after transvenous embolization. Based on the pathophysiology of cervical pain, we presumed that the blood flow dynamics of the odontoid arcade was involved. As expected, after the blood flow near the transverse ligament of the atlas was normalized the symptoms disappeared.

CONCLUSION

We could not find previous reports of ACC-dAVF where the main symptom was cervical pain. We report the possibility of a mechanism of dAVF different from those reported previously.

Subarachnoid Hemorrhage with Concurrent Dural and Perimedullary Arteriovenous Fistulas at Craniocervical Junction: Case Report and Literature Review

BACKGROUND

The association between a dural arteriovenous fistula (dAVF) and perimedullary arteriovenous fistula (AVF) is rarely observed at the craniocervical junction (CCJ). We present a case of subarachnoid hemorrhage (SAH) with concurrent dAVF and perimedullary AVF at the CCJ. Here, we describe the cause of bleeding and the process of determining whether it was a varix or an arterial aneurysm.

CASE DESCRIPTION

A 69-year-old man with SAH visited the emergency department. A dAVF at the CCJ was detected on digital subtraction angiography (DSA). However, after 3 weeks, when the DSA was repeated, a perimedullary AVF and varix were identified. We performed an endovascular treatment, but because the perimedullary AVF remained, we performed a direct surgery. The patient was discharged without weakness, but this left abducens nerve palsy remained.

CONCLUSIONS

In recent reports, SAH caused by concurrent dAVF and perimedullary AVF raised the possibility of an arterial aneurysm. However, in this case, the possibility of venous bleeding was high and a varix rather than an aneurysm was observed. On the basis of the reported cases, concurrent dAVF and perimedullary AVF at the CCJ is a "middle-flow arteriovenous shunt" that may induce a varix or an arterial aneurysm.

[Subcortical calcification on CT in Borden type III intracranial dural arteriovenous fistula]

We herein report a 67-year-old female who presented with progressive dementia and disturbance of consciousness. Brain CT showed multiple subcortical calcifications with edema. Enhanced CT showed multiple abnormal vessels in the left hemisphere. Electroencephalography indicated diffuse spike and slow wave complex, so non-convulsive status epilepticus was diagnosed. Cerebral angiography revealed several feeder arteries with retrograde leptomeningeal venous drainage. We diagnosed her with Borden type III cerebral dural arteriovenous fistulas. Trans-arterial embolization with n-butyl-2-cyanoacrylate was performed, and she has experienced no epileptic attacks for at least ten months. Calcification changes are sometimes seen in Borden type II dural arteriovenous fistulas but not in aggressive types, such as Borden type III. It is important to suspect dural arteriovenous fistulas when we encounter patients with progressive dementia or/and epilepsy with cerebral calcification lesions, as this may be a treatable disease condition.

Multiple aneurysms on the subarcuate artery arising from the anterior inferior cerebellar artery in a patient with a Borden type I transverse-sigmoid dural arteriovenous fistula manifesting as subarachnoid hemorrhage: A case report

BACKGROUND

Peripheral anterior inferior cerebellar artery (AICA) aneurysms are rare and commonly associated with vascular malformations, such as cerebellar arteriovenous malformations (AVMs). We present a case wherein multiple AICA feeding aneurysms on the subarcuate artery as a feeding artery of a Borden type I transverse-sigmoid dural arteriovenous fistula (dAVF) manifested as subarachnoid hemorrhage.

CASE DESCRIPTION

A 67-year-old woman presented with acute severe headache. Brain computed tomography (CT) demonstrated subarachnoid hemorrhage mainly in the posterior fossa. A transverse-sigmoid dAVF was detected on magnetic resonance angiography (MRA) and three-dimensional-CT angiography (3D-CTA), with no cortical venous reflex. The patient underwent conventional angiography, which showed multiple aneurysms on a small branch of the AICA, feeding a transverse-sigmoid dAVF (Borden type I). The AICA aneurysms seemed flow dependent and ruptured owing to high-flow arteriovenous shunts through the dAVF. Based on the source images of the MRA, the small artery arising from the AICA was considered the subarcuate artery, and it was confirmed on 3D-CTA after the artery was successfully embolized with Onyx without any complications. Multiple aneurysms on the subarcuate artery are extremely rare, and the artery has not been identified as a feeding artery of the transverse-sigmoid dAVF.

CONCLUSION

A rare case of multiple ruptured aneurysms on the subarcuate artery was reported in a patient with a Borden type I dAVF at the transverse-sigmoid sinuses manifesting as subarachnoid hemorrhage. Onyx embolization of the parent artery occlusion was feasible and useful in treating this type of feeding artery aneurysm of the AICA with a dAVF.

Evaluation of stereotactic radiosurgery for cerebral dural arteriovenous fistulas in a multicenter international consortium

OBJECTIVE

In this multicenter study, the authors reviewed the results obtained in patients who underwent Gamma Knife radiosurgery (GKRS) for dural arteriovenous fistulas (dAVFs) and determined predictors of outcome.

METHODS

Data from a cohort of 114 patients who underwent GKRS for cerebral dAVFs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as dAVF obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and dAVF characteristics were assessed to determine predictors of outcome in a multivariate logistic regression analysis; dAVF-free obliteration was calculated in a competing-risk survival analysis; and Youden indices were used to determine optimal radiosurgical dose.

RESULTS

A mean margin dose of 21.8 Gy was delivered. The mean follow-up duration was 4 years (range 0.5-18 years). The overall obliteration rate was 68.4%. The postradiosurgery actuarial rates of obliteration at 3, 5, 7, and 10 years were 41.3%, 61.1%, 70.1%, and 82.0%, respectively. Post-GRKS hemorrhage occurred in 4 patients (annual risk of 0.9%). Radiation-induced imaging changes occurred in 10.4% of patients; 5.2% were symptomatic, and 3.5% had permanent deficits. Favorable outcome was achieved in 63.2% of patients. Patients with middle fossa and tentorial dAVFs (OR 2.4, p = 0.048) and those receiving a margin dose greater than 23 Gy (OR 2.6, p = 0.030) were less likely to achieve a favorable outcome. Commonly used grading scales (e.g., Borden and Cognard) were not predictive of outcome. Female sex (OR 1.7, p = 0.03), absent venous ectasia (OR 3.4, p < 0.001), and cavernous carotid location (OR 2.1, p = 0.019) were predictors of GKRS-induced dAVF obliteration.

CONCLUSIONS

GKRS for cerebral dAVFs achieved obliteration and avoided permanent complications in the majority of patients. Those with cavernous carotid location and no venous ectasia were more likely to have fistula obliteration following radiosurgery. Commonly used grading scales were not reliable predictors of outcome following radiosurgery.

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

BACKGROUND

Spinal dural arteriovenous fistulas (sdAVF) with rapid deterioration are a known clinical phenomenon but have been rarely reported in the past. Clinical and radiologic features of these fistulas are analyzed for this study.

MATERIAL AND METHODS

We retrospectively reviewed our medical records for sdAVF patients who were treated in our center between 2006 and 2017. Our cohort was dichotomized in two groups; a) patients with acute/ subacute onset and rapid deterioration within a period of ≤6 months, b) patients with chronic progressive deterioration within a period of >6 months. MR findings at time of diagnosis were re-evaluated. All patients were treated microsurgically. Follow-up data were included.

RESULTS

Data of forty patients were available for this study. Rapid deterioration was observed in 13/40 (32.5%) patients. AL-score at time of diagnosis did not differ between both groups (3.2 ± 1.2 vs 3 ± 2, p = .78). Patients with rapid deterioration showed significantly more prominent arterialized perimedullay veins at time of diagnosis (p < .05). At the last follow-up (53 ± 3 months), patients with rapid deterioration improved up to one point on AL-scores (from 3.2 ± 1.4 to 2 ± 1.6) and those with chronic progressive deterioration were unchanged (from 3 ± 1.6 to 3 ± 1.7).

CONCLUSION

Patients with rapid deterioration in our group (32.5%) presented with a significantly more prominent appearance of the arterialized perimeduallry veins. This may reflect, in the earlier phase of the disease, a better compensation of the venous hypertension as well as the associated venous outlet disorder of the spinal cord. This may also explain the better outcome of these patients.

Comparison of Endovascular Embolization and Surgery in the Treatment of Spinal Intradural Dorsal Arteriovenous Fistulas

BACKGROUND

We compared the outcomes of endovascular embolization and surgery and investigated the factors affecting the clinical outcomes of spinal intradural dorsal arteriovenous fistulas (SIDAVFs).

METHODS

The medical records of 26 patients who had undergone endovascular embolization or surgery for SIDAVFs from 2004 to 2014 were retrospectively reviewed. The recurrence rate and clinical outcomes for each treatment modality were compared. Multivariate analysis was used to identify significant factors influencing the clinical outcomes using the Aminoff and Logue (AL) score.

RESULTS

Of the 26 patients, 14 (56%) had undergone endovascular embolization and 11 (44%) had undergone surgery as the initial treatment. Embolization was applied as the primary treatment for most patients. Surgery was chosen for patients with difficult superselection (n = 5), multiple feeders (n = 2), or easy surgical accessibility (n = 4). Of the 14 patients who had undergone embolization as initial treatment, 5 (36%) had developed a recurrence within an average of 29.6 months (range, 2-87). One patient with recurrent SIDAVF was treated with repeat embolization and four with surgery. None of patients in the surgical group developed recurrence. Embolization as the initial treatment resulted in significantly greater recurrence compared with surgery (odds ratio, 2.222; 95% confidence interval, 1.369-3.608; P = 0.046). Surgery resulted in better clinical outcomes than embolization (P = 0.021). The final AL score was also strongly affected by the preoperative AL score, micturition score, and recurrence (P = 0.000, P = 0.000, and P = 0.011, respectively).

CONCLUSIONS

Our results have shown that surgery results in a low recurrence rate and superior clinical outcomes. A multidisciplinary and ordered decision is crucial for the treatment choice to ensure better outcomes, especially for patients with a definite neurologic deficit at diagnosis.

Vagal Nerve Palsy After Transarterial Embolization of Transverse-Sigmoid Dural Arteriovenous Fistula Using Onyx

OBJECTIVE

We report a case of a 70-year-old man who developed a transverse-sigmoid dural arteriovenous fistula (TS-DAVF) that was successfully treated by transarterial embolization (TAE) with Onyx.

CASE PRESENTATION

The patient presented with sudden and progressive disturbance of consciousness and left hemiparesis. Magnetic resonance imaging (MRI) revealed venous infarction and hemorrhagic changes with brain swelling in the right parietal lobe. Angiography revealed a right TS-DAVF and multiple occlusions with retrograde leptomeningeal venous drainage into the cortical veins. The TS-DAVF was graded as Borden type III and Cognard type IIa+b. Because of its progressive clinical nature and wide distribution of DAVF in the occluded sinus wall, he underwent emergent TAE with liquid embolic materials including n-butyl cyanoacrylate and Onyx under informed consent by his family. Complete obliteration of the TS-DAVF was achieved, leading to a marked amelioration of symptoms, and MRI after treatment confirmed a decrease in the brain swelling. However, he suffered transient dysphagia due to right vagal nerve palsy caused by occlusion of vasa nervorum of ascending pharyngeal artery. He returned home 5 months later with a modified Rankin Scale of 1.

CONCLUSIONS

TAE with Onyx appears to be effective for aggressive TS-DAVF with a widely distributed shunt. However, the blood supply to the cranial nerves and potentially dangerous anastomoses between the external-internal carotid artery and vertebral artery should be taken into account to avoid serious complications.

Dural Arteriovenous Fistulas at the Craniocervical Junction: A Series Case Report

BACKGROUND

Craniocervical junction dural arteriovenous fistulas (CJDAVFs) are rare vascular malformations with unclear clinical characteristics. This study investigated the clinical characteristics and outcomes of patients with CJDAVFs.

METHODS

Thirty-eight patients with CJDAVFs who had undergone either conservative or surgical treatment were retrospectively analyzed.

RESULTS

Eleven (28.9%) patients were women and 27 (71.1%) were men (median age, 52.5 years). Two (5.3%) had myelopathy, and 36 (94.7%) had subarachnoid hemorrhage (SAH). Three patients had SAH recurrence before treatment. Five patients (13.9%) with SAH initially had negative results on angiography, which may have been due to a low-flow fistula without varicose veins (P = 0.034) and acute hydrocephalus (P = 0.084). Coincidental vascular lesions were noted in 5 patients (13.2%). Caudal drainage was mainly found in patients with myelopathy, whereas superolateral drainage was frequently observed in patients with SAH (P = 0.021). Thirty-six (94.7%) patients underwent microsurgery; of these, 33 (91.7%) had favorable outcomes and 3 (8.3%) had unfavorable outcomes. The main neurosurgical complications included acute hydrocephalus in 4 (10.5%) and new-onset mild persistent myelopathy in 6 (15.7%). According to the univariate analysis, the presence of myelopathy predicted poor outcomes, whereas SAH predicted favorable outcomes (P = 0.004). However, the multivariate analysis did not show statistical significance.

CONCLUSIONS

SAH is a common presenting sign of CJDAVF that may be overlooked on initial cerebral angiography, especially in patients with acute hydrocephalus and a low-flow fistula without varicose veins. Microsurgery involving disconnecting the draining vein is effective and beneficial. Further studies should be performed to investigate predictive factors influencing the prognosis.

Retrieval of a migrated N-butyl-2 cyanoacrylate cast using a snare-kit system during dural AVF embolization: A case report

N-butyl-2 cyanoacrylate (NBCA) is a liquid embolic material that is widely used in various endovascular procedures because of its permanent and rapid vascular occluding effect regardless of the coagulation profile of the patient. However, NBCA migration to unintended vessels may result in serious complications. This report describes the retrieval of a migrated NBCA cast from the transverse-sigmoid sinus during dural arteriovenous fistula embolization using a transvenous snaring technique.

Recurrent Secondary Trigeminal Neuralgia Caused by Obliterated Tentorial Dural Arteriovenous Fistula Cured with Surgical Resection: Case Report and Literature Review

BACKGROUND

Trigeminal neuralgia (TN) caused by a tentorial dural arteriovenous fistula (TDAVF) is quite rare. To date, only 10 cases and 2 small case series have been reported in this regard, and most were treated with either embolization or surgery. Here, we report a unique case of a TDAVF presented as TN, which was embolized with Onyx first and resected later.

CASE DESCRIPTION

A 57-year-old male presented with right-sided TN. Magnetic resonance imaging revealed a variceal venous dilation occupying the right lateral pontine cistern and multiple venous flow void signals adjacent to the right trigeminal nerve root entry zone. Digital subtraction angiography revealed the right TDAVF, which was completely embolized with transarterial Onyx later. The patient remained symptom free for 1 year before TN recurred. Digital subtraction angiography did not exhibit the recurrence of fistula. After resection of embolized dilated veins, the symptom alleviated and the patient remained symptom free for the 5-month follow-up to date.

CONCLUSIONS

Even complete obliteration of fistula could cause the recurrence of neuralgia, and resection of embolized dilated veins might be effective for the treatment of TN in such recurrent cases.

[The spinal dural arteriovenous fistula is an underdiagnosed vascular malformation]

The spinal dural arteriovenous fistula is the most common spinal vascular malformation, and it is severely underdiagnosed. The symptoms can mimic those of spinal stenosis. Today, the diagnosis is made by an advantageous combination of MR time-resolved imaging of contrast kinetics and digital subtraction angiography posing low risk to the patient. Treatment is primarily direct microsurgical obliteration. Early treatment is essential, since outcome is dependent on preoperative clinical status.

Transarterial Embolization of Cavernous Sinus Dural Arteriovenous Fistulas with Ipsilateral Inferior Petrosal Sinus Occlusion via the Ascending Pharyngeal Artery

BACKGROUND

Although the ipsilateral inferior petrosal sinus (IPS) is preferred for treatment of cavernous sinus dural arteriovenous fistulas (CS-dAVFs), this method is problematic if ipsilateral IPS is occluded. We describe our experience in treating CS-dAVFs with ipsilateral IPS occlusion via the ascending pharyngeal artery (APA).

METHODS

Between January 2013 and June 2017, of 36 CS-dAVFs, 23 with ipsilateral IPS occlusion were identified. Clinical charts, procedural data, angiographic results, and follow-up data were retrospectively reviewed.

RESULTS

Of 23 CS-dAVFs, 16 displayed a single or dominant feeding APA on cerebral angiography, of which 13 were treated via the APA initially. Fistulas were occluded successfully through the neuromeningeal trunk of the APA in 7 cases and through the superior pharyngeal branch of the APA in 3 cases. Glue leakage occurred in 2 cases via the superior pharyngeal branch of the APA, and superior pharyngeal branch rupture occurred during superselection of the microguidewire in 1 patient, who was treated by opening the occluded ipsilateral IPS. During the follow-up period, 12 of 13 patients had complete occlusion, and no cranial nerve palsy occurred.

CONCLUSIONS

CS-dAVF with ipsilateral IPS occlusion can be treated via various methods. Embolization through the APA as an initial access is a reasonable choice.

Spinal dural arteriovenous fistula: delay to radiological diagnosis and sources of radiological error

AIM

To highlight the magnetic resonance imaging (MRI) signs associated with spinal dural arteriovenous fistula (SDAVF) through categorisation of sources of radiological error and investigation of the delay to radiological diagnosis.

MATERIAL AND METHODS

This was a retrospective, observational study of cases referred to a neuroscience centre over 11 years. All patients who underwent spinal digital subtraction angiography (DSA) with a subsequent diagnosis of SDAVF were identified. Prior imaging was reviewed and compared with the formal reports issued.

RESULTS

Thirty-seven patients with SDAVF were initially imaged in seven institutions. Radiological abnormalities including intradural vessels (37/37, 100%), cord T2 signal change (34/37, 91.9%), and cord expansion (26/37, 70.2%) were present on prior MRI. These signs were not recognised in 22/37 (59.5%), 7/34 (20.5%), and 15/26 (57.7%) of cases, respectively. Increased T2 signal in the cord was the most commonly identified sign (27/34; 79.4%), but prompted either no diagnosis (7/34; 20.5%) or differential diagnoses including ischaemic, inflammatory, or neoplastic aetiologies or a syrinx in 11/34 (32.4%). An appropriate diagnosis was made on initial MRI in 15 patients (40.5%). The time from initial imaging to diagnosis was significantly delayed for those patients who did not have an arteriovenous vascular aetiology included in the initial differential diagnosis (281 (423.3) days versus 22 (15.7) days, p=0.03).

CONCLUSION

SDAVF have imaging features that are frequently missed or misinterpreted. This results in a significant delay to definitive diagnosis and therefore treatment.

Arterial spin labeling MR imaging aids to identify cortical venous drainage of dural arteriovenous fistulas

Cortical venous drainage (CVD) increases the probability of intracranial hemorrhage and mortality rate of dural arteriovenous fistulas (DAVF). Although digital subtraction angiography (DSA) is the most accurate method to determine CVD in DAVFs, this modality has limitations due to its invasive nature and radiation issues. The purpose of this study was to evaluate the diagnostic utility of arterial spin-labeling perfusion-weighted images (ASL-PWI) to identify CVD in patients with DAVF.The Institutional Review Board of our hospital approved this retrospective study. ASL-PWI features of 22 patients with DAVF were retrospectively reviewed for the presence of bright signal intensity in cortical veins and brain parenchyma. DAVF with bright signal intensity in cortical veins and/or brain parenchyma was regarded as having CVD. Using DSA as a reference standard, sensitivity, specificity, positive predictive value, and negative predictive value of ASL-PWI for detecting CVD were calculated.Based on DSA features, 11 (11/22, 50%) patients were classified as having "aggressive" pattern with CVD. Eleven (11/22, 50%) patients also showed bright signal intensity in cortical veins (9/22, 41%) and/or brain parenchyma (4/22, 18%) on ASL-PWI. The 11 patients who had "Aggressive" pattern on DSA were the same 11 patients who were classified as having "aggressive" pattern on ASL-PWI. ASL-PWI showed perfect diagnostic performance for identifying CVD with sensitivity, specificity, positive predictive value, and negative predictive value of 100% for all.Thus, ASL-PWI could be used as a noninvasive mean to predict the presence of CVD in patients with DAVFs. It has the potential as a screening tool to evaluate DAVF prior to invasive DSA.

Eight-and-a-Half Syndrome: A Combination of Intracranial Capillary Telangiectasia and Hematencephalon

Eight-and-a-half syndrome, a combination of one-and-a-half syndrome and ipsilateral facial palsy, was first described by Eggenberger in 1998. Intracranial capillary telangiectasia (ICT) is a rare type of latent cerebral vascular malformation characterized by a number of small, dilated, and thin-walled blood capillaries with normal brain tissues between them. Susceptibility weighted imaging is the recommended diagnostic method to detect ICT. Oommen once reported 1 case about pontine hemorrhage causing Fisher one-and-a-half syndrome with facial paralysis. Here, we report a case with regard to pontine tegmentum ICT and hematencephalon presenting as eight-and-a-half syndrome.

Dural Arterivenous Fistula at the Cavernous Sinus Diagnosed by Arterial Spin-labeled Imaging

We herein report a case of dural arteriovenous fistula (DAVF) at the cavernous sinus that was diagnosed by arterial spin-labeled imaging (ASL). A 67-year-old woman was referred to our hospital due to double vision and bilateral conjunctival injection. Conventional magnetic resonance imaging findings were normal. However, abnormal hyperintense signals on ASL were detected. Furthermore, the abnormality disappeared after successful endovascular embolization. Although conventional digital subtraction angiography is the standard tool for diagnosing DAVF, we speculated that ASL might be useful to this end as well.

Polymorphism in dural arteriovenous fistula: matrix metalloproteinase-2-1306 C/T as a potential risk factor for sinus thrombosis

Essentials Sinus thrombosis may play a crucial role in development of dural arteriovenous fistula (DAVF). Little is known about the association between gene polymorphism and the development of DAVF. MMP-2-1306 C/T showed a higher prevalence rate in DAVF cases with sinus thrombosis. MMP-2-1306C/T polymorphism is likely a potential risk factor for sinus thrombosis in DAVF.

SUMMARY

Background Dural arteriovenous fistula (DAVF) is a rare but important cerebrovascular disorder in adults. Little is known about the molecular genetic pathogenesis underlying DAVF development. Objectives To investigate the associations of gene polymorphisms and DAVF. Materials and Methods By the use of real-time PCR genotyping, seven single-nucleotide polymorphisms (SNPs) of angiogenesis-related genes were analyzed in 72 DAVF patients. Pertinent clinical and imaging data were subgrouped on the basis of location (cavernous sinus versus lateral sinus), lesions (single versus multiple), cerebral venous reflux (CVR) grading (Borden I versus Borden II/III), and sinus thrombosis (with versus without). Results We found that individuals carrying the polymorphic allele of matrix metalloproteinase (MMP)-2-1306 C/T (rs243865) had a significantly increased risk of sinus thrombosis in DAVF (odds ratio 6.2; 95% confidence interval 1.7-22.9). There was a weak difference in associations of tissue inhibitor of metalloproteinase (TIMP)-2 (rs2277698) gene polymorphism and DAVF patients subgrouped by CVR grading. Conclusions These preliminary results indicate that MMP-2-1306 C/T, but not MMP-9, TIMP-1, TIMP-2, and vascular endothelial growth factor A SNP variants, is a risk factor for the development of sinus thrombosis in DAVF patients.

Arterial Spin-Labeling Improves Detection of Intracranial Dural Arteriovenous Fistulas with MRI

BACKGROUND AND PURPOSE

Intracranial dural arteriovenous fistulas carry a risk of substantial neurologic complications but can be difficult to detect on structural MR imaging and TOF-MRA. The purpose of this study was to assess the accuracy and added value of 3D pseudocontinuous arterial spin-labeling MR imaging for the detection of these lesions.

MATERIALS AND METHODS

This retrospective study included 39 patients with a dural arteriovenous fistula and 117 controls who had undergone both DSA and MR imaging with pseudocontinuous arterial spin-labeling. Two neuroradiologists blinded to the DSA results independently assessed MR imaging with and without pseudocontinuous arterial spin-labeling. They recorded specific signs, including venous arterial spin-labeling signal, and the likelihood of a dural arteriovenous fistula using a 5-point Likert scale. Logistic regression and receiver operating characteristic analyses were performed to determine the accuracy of specific signs and the added value of pseudocontinuous arterial spin-labeling. Interobserver agreement was determined by using κ statistics.

RESULTS

Identification of the venous arterial spin-labeling signal had a high sensitivity (94%) and specificity (88%) for the presence a dural arteriovenous fistula. Receiver operating characteristic analysis showed significant improvement in diagnostic performance with the addition of pseudocontinuous arterial spin-labeling in comparison with structural MR imaging (Δarea under the receiver operating characteristic curve = 0.179) and a trend toward significant improvement in comparison with structural MR imaging with time-of-flight MRA (Δarea under the receiver operating characteristic curve = 0.043). Interobserver agreement for the presence of a dural arteriovenous fistula improved substantially and was almost perfect with the addition of pseudocontinuous arterial spin-labeling (κ = 0.92).

CONCLUSIONS

Venous arterial spin-labeling signal has high sensitivity and specificity for the presence of a dural arteriovenous fistula, and the addition of pseudocontinuous arterial spin-labeling increases confidence in the diagnosis of this entity on MR imaging.

[Tentorial Dural Arteriovenous Fistula Presenting with Ocular Symptoms:A Case Report]

Tentorial dural arteriovenous fistula(dAVF)is classified as Cognard 4 with a high risk of aggressive feature, such as intracranial hemorrhage, venous infarction, and intracranial hypertension. We report a rare case presenting with ocular symptoms caused by tentorial dAVF. A 59-year-old man presented with progressive chemosis and exophthalmos of his left eye. Angiography showed a tentorial dAVF that was primarily fed by the middle meningeal artery and the meningohypophyseal artery. The AVF drained into the superior ophthalmic vein and the cerebellar cortical vein via an enlarged petrosal vein. Because transarterial Onyx embolization resulted in incomplete obliteration of the fistula, he underwent microsurgery via a suboccipital approach to obliterate the shunt. Postoperative angiography showed complete obliteration of the shunt. His ocular symptoms rapidly cured. We present this rare case and discuss the pathomechanism associated with the development of ocular symptoms secondary to a tentorial dAVF from the viewpoint of microvascular anatomy.