Shunted pouches of cavernous sinus dural AVFs: evaluation by 3D rotational angiography.

INTRODUCTION: The aims of this study were to evaluate the angioarchitecture of cavernous sinus dural arteriovenous fistulas (CSdAVFs), including the number and location of shunted pouches (SPs), and to evaluate whether the location and number of the SPs affect the outcomes of transvenous embolization of CSdAVFs. METHODS: Nineteen consecutive cases of CSdAVFs that underwent rotational angiography and transvenous embolization were reviewed. Multiplanar reconstruction images of rotational angiography and selective angiography were reviewed with particular interest in the SPs. Relationships of the locations and number of SPs with the results of transvenous embolization were statistically analyzed. RESULTS: All cases showed SPs, with numbers ranging from 1 to 4 (mean, 2.2). The location of the SPs was "posteromedial" in 16, "posterolateral" in 13, "lateral" in 6, and "medial" in 3 patients. Six cases showed posteromedial SPs alone, and three cases showed posterolateral SPs alone. The other 10 cases showed multiple locations of SPs. All cases were treated by transvenous embolization with sinus packing (n = 11) or selective embolization of the SP (n = 8). Complete occlusion of dAVF was obtained in 16 cases immediately after embolization. Locations of SPs and drainage types were significantly associated with the immediate angiographic results (p < 0.01). CONCLUSION: The SP of CSdAVFs is often multiple and is located posteriorly to the CS. The number and location of SPs affect immediate angiographic results of transvenous embolization.

Anatomical variations in termination of the uncal vein and its clinical implications in cavernous sinus dural arteriovenous fistulas.

INTRODUCTION: The aim of the study was to investigate the variations in the uncal vein (UV) termination and its clinical implication in cavernous sinus dural arteriovenous fistulas (CSDAVFs). METHODS: Biplane cerebral angiography in 80 patients (160 sides) with normal cerebral venous return (normal group) was reviewed with special interest in the termination of the UV. Frequency and types of uncal venous drainage from CSDAVFs in consecutive 26 patients were also analyzed. RESULTS: In the normal group, the UV was identified in 118 sides (74 %). The UV terminated into cavernous sinus (CS) in 41 sides (34 %), the superficial middle cerebral vein (SMCV) in 58 sides (48 %), the laterocavernous sinus (LCS) in 15 sides (13 %), and the paracavernous sinus (PCS) in 4 sides (3 %). Cerebral venous blood via the UV draining into the CS directly (n=41) or through the SMCV and/or the LCS (n=45) was observed in 86 sides (54 %). Uncal venous drainage from CSDAVFs was found in 13 patients (50 %). The CSDAVFs drained directly into the UV in two patients, drained via LCS into the UV in two patients, and drained through the SMCV into the UV in the remaining nine patients. All cases were successfully treated by transvenous embolization with special attention given to uncal venous drainage. CONCLUSION: There are several variations in UV termination according to the embryological development of the primitive tentorial sinus and the deep telencephalic vein. Careful attention should be paid to uncal venous drainage for the treatment of CSDAVFs.

Maxillary artery: functional and imaging anatomy for safe and effective transcatheter treatment.

The maxillary artery is a terminal branch of the external carotid artery. Although the main maxillary artery trunk and most of its branches course within the extracranial space and supply the organs and muscles of the head and neck, other surrounding soft tissues, and the oral and rhinosinusal cavities, other branches supply the dura mater and cranial nerve and can anastomose to the internal carotid artery (ICA). Various pathologic conditions of the intracranial, head, and neck regions can involve the branches of the maxillary artery. Many of these diseases can be treated with endovascular approaches; however, there is a potential risk of complications in the brain parenchyma and cranial nerves related to the meningoneuronal arterial supply and anastomoses to the ICA. Therefore, familiarity with the functional and imaging anatomy of the maxillary artery is essential. In the past, conventional angiography has been the standard imaging technique for depicting the maxillary artery anatomy and related pathologic findings. However, recent advances in computed tomographic, magnetic resonance, and rotational angiography have further elucidated the maxillary artery anatomy by means of three-dimensional representations. Understanding the functional and imaging anatomy of the maxillary artery allows safe and successful transcatheter treatment of pathologic conditions in the maxillary artery territories.

Spinal ventral epidural arteriovenous fistulas of the lumbar spine: angioarchitecture and endovascular treatment.

INTRODUCTION: Spinal ventral epidural arteriovenous fistulas (EDAVFs) are relatively rare spinal vascular lesions. We investigated the angioarchitecture of spinal ventral EDAVFs and show the results of endovascular treatment. METHODS: We reviewed six consecutive patients (four males and two females; mean age, 67.3 years) with spinal ventral EDAVFs treated at our institutions from May 2011 to October 2012. All patients presented with progressive myelopathy. The findings of angiography, including 3D/2D reformatted images, treatments, and outcomes, were investigated. A literature review focused on the angioarchitecture and treatment of spinal ventral EDAVFs is also presented. RESULTS: The EDAVFs were located in the ventral epidural space at the L1-L5 levels. All EDAVFs were supplied by the dorsal somatic branches from multiple segmental arteries. The ventral somatic branches and the radiculomeningeal arteries also supplied the AVFs in two patients. The AVFs drained via an epidural venous pouch into the perimedullary vein in four patients and into both the perimedullary vein and paravertebral veins in two patients. Four cases without paravertebral drainage were treated by transarterial embolization with diluted glue, and two cases with perimedullary and paravertebral drainages were treated by transvenous embolization alone or in combination with transarterial embolization. An angiographic cure was obtained in all patients. Clinical symptoms resolved in two patients, markedly improved in three patients, and minimally improved in one patient. CONCLUSION: In our limited experience, spinal ventral EDAVFs were primarily fed by somatic branches. EDAVFs can be successfully treated by endovascular techniques selected based on the drainage type of the AVF.

Utility of a Steerable Microcatheter for the Selective Transvenous Embolization of Dural Arteriovenous Fistulas.

Objective: Selective transvenous embolization (sTVE) is an effective technique for treating dural arteriovenous fistulas (DAVFs); however, selective catheterization into the shunted pouch is often difficult due to the acute angle of the access route between the target pouch and dural sinus. We present our initial experience using a steerable microcatheter (SM) to manually control the tip angle for selective catheterization and sTVE of DAVFs. Methods: Thirteen consecutive cases of DAVFs and 16 procedures that involved sTVE using SM between October 2016 and October 2018 were reviewed. SMs were used for selective catheterization of shunted venous pouches and/or the affected sinus and coil embolization. We evaluated the maneuverability of the SM, the success of selective catheterization into the target lesions, and the results of endovascular treatments. Results: Endovascular procedures were performed in a single session in 10 cases and in two staged sessions in 3 cases. There was no difficulty in maneuverability of the SM. Successful selective catheterization was achieved in 26 of 27 target lesions. Immediately after embolization, angiography showed complete occlusion in 10 cases and marked reduction in 3 cases. During 40.9 months of mean follow-up, 12 cases showed complete occlusion and one case showed a small residual shunt on MRI. Procedure-related complications of spontaneous thrombosis of the affected sinus were observed in one case. There were no cases of recurrence or exacerbation during follow-up. Conclusion: SM is useful for selective catheterization for target lesions during sTVE of DAVFs.

[Effect of Gorei-san with tranexamic acid for preventing recurrence of chronic subdural hematoma].

OBJECT: Chronic subdural hematoma is often seen in elderly patients. One burr hole surgery with subdural drainage has been performed and prognosis is good, but the recurrence rate is still about 10%. To prevent the recurrence, we used Kampo-medicine Gorei-san with tranexamic acid after surgery. The purpose of this study is to investigate if the recurrence is able to prevent by using these drugs. METHODS: From January 2008 to December 2010, 199 consecutive cases with chronic subdural hematoma were examined at Nagatomi Neurosurgical Hospital. Patients were divided into four groups according to the administered drugs; Gorei-san, tranexamic acid, Gorei-san with tranexamic acid and no drug groups. The recurrence rate was compared between each group. The chi-square test was performed as a statistical analysis. RESULTS: In all patients, the mean age was 77.7±10.5 years. There were 140 males and 59 females. Overall recurrence rate was 7.0%. Each recurrence rate was 8.3% in the Gorei-san administration group, and 10.9% in the tranexamic acid group, and 2.9% in Gorei-san with tranexamic acid group, and 5.7% in the no-drug group. There was no significant difference between the four groups in statistical analysis. CONCLUSIONS: Gorei-san with the tranexamic acid administration group had the minimum recurrence. There was no significant difference but these drugs would be preventable recurrence of chronic subdural hematoma. We need to accumulate more cases as a prospective study in the future.

High D-Dimer Concentration Is a Significant Independent Prognostic Factor in Patients with Acute Large Vessel Occlusion Undergoing Endovascular Thrombectomy.

OBJECTIVE: To investigate prognostic factors that affect the modified Rankin Scale score at 3 months after onset of acute stroke in patients with large vessel occlusion who underwent endovascular thrombectomy. METHODS: We retrospectively examined 87 consecutive patients who underwent endovascular cerebral thrombectomy for acute anterior circulation large vessel occlusion at Oita University Hospital and Nagatomi Neurosurgery Hospital from January 2014 to December 2020. RESULTS: Age, National Institutes of Health Stroke Scale score, and D-dimer concentration on admission were significant univariate prognostic factors related to modified Rankin Scale score at 3 months after stroke onset. Multivariate logistic regression analysis showed that D-dimer concentration was the only significant independent prognostic factor. The area under the receiver operating characteristic curve for D-dimer concentration and modified Rankin Scale score at 3 months was 0.715 (95% confidence interval 0.599-0.831); sensitivity and specificity were 60.6% and 80.0%, respectively, using a 1.9 µg/mL cutoff value. CONCLUSIONS: Prognosis may be worse in patients undergoing acute endovascular cerebral thrombectomy with high D-dimer concentration on admission. Other treatment options should be considered for these patients.

Selective transvenous embolization combined with balloon angioplasty of the occluded inferior petrosal sinus for the treatment of cavernous sinus dural arteriovenous fistulas.

BACKGROUND AND PURPOSE: Angioplasty of the dural sinus has rarely been performed for the treatment of cavernous sinus dural arteriovenous fistulas. We evaluated the efficacy of selective transvenous embolization (TVE) combined with balloon angioplasty of the occluded inferior petrosal sinus (IPS) for the treatment of cavernous sinus dural arteriovenous fistulas (CSDAVFs). MATERIALS AND METHODS: A total of 8 consecutive patients with CSDAVFs with occlusion of the IPS treated by selective TVE with balloon angioplasty of the IPS from July 2018 to January 2019 were retrospectively reviewed. There were 6 females and 2 males with an average age of 77.6 years. All patients showed ocular symptoms. Angiography showed cortical venous reflux in 7 cases and localized shunted pouches at the medial portion of the cavernous sinus, intercavernous sinus, or laterocavernous sinus. Selective TVE was performed via the occluded IPS with bilateral femoral venous approaches, and the occluded IPS was reconstructed by angioplasty with a 2- to 3-mm diameter balloon during or after selective TVE. RESULTS: CSDAVFs disappeared immediately after treatment, and the occluded IPSs were successfully reconstructed with re-establishment of normal antegrade venous flow in all cases. No complications were observed, and symptoms resolved within 2 weeks after treatment. During the 7-month mean follow-up period (range 1-12 months), no cases showed recurrence of CSDAVFs. CONCLUSION: Selective TVE combined with balloon angioplasty of the occluded IPS is safe and effective for the treatment of CSDAVFs and re-establishes normal venous circulation in selected cases with localized shunted pouches.

Endovascular recanalization of acute intracranial vertebrobasilar artery occlusion using local fibrinolysis and additional balloon angioplasty.

INTRODUCTION: Vertebrobasilar artery occlusion (VBO) produces high mortality and morbidity due to low recanalization rate utilization in endovascular therapy. The use of percutaneous transluminal angioplasty (PTA) to improve recanalization rate additional to local intra-arterial fibrinolysis (LIF) was investigated in this study. Results obtained following recanalization therapy in acute intracranial VBO are reported. METHODS: Eighteen consecutive patients with acute VBO underwent LIF with or without PTA, from August 2000 to May 2006. Eight patients were treated using LIF alone, and ten required additional PTA. Rate of recanalization, neurological status before treatment, and clinical outcomes were evaluated. RESULTS: Of 18 patients, 17 achieved recanalization. One procedure-related complication of subarachnoid hemorrhage occurred. Overall survival rate was 94.4% at discharge. Seven patients achieved good outcomes [modified Rankin scale (mRS) 0-2], and the other 11 had poor outcomes (mRS 3-6). Five of six patients who scored 9-14 on the Glasgow Coma Scale (GCS) before treatment displayed good outcomes, whereas ten of 12 patients who scored 3-8 on the GCS showed poor outcomes. GCS prior to treatment showed a statistically significant correlation to outcomes (p < 0.05). Moreover, the National Institutes of Health Stroke Scale (NIHSS) before treatment correlated well with mRS (correlation coefficient 0.487). No statistical difference between the good and poor outcome groups was observed for the duration of symptoms, age, etiology, and occlusion site. CONCLUSIONS: Endovascular recanalization can reduce mortality and morbidity of acute VBO. Good GCS and NIHSS scores prior to treatment can predict the efficacy of endovascular recanalization.

Diploic arteriovenous fistulas with marked cortical venous reflux.

Diploic arteriovenous fistulas are rare arteriovenous shunts involving the skull, which often drain antegradely into the internal or external jugular veins. Diploic arteriovenous fistulas with marked cortical venous reflux are extremely rare. Here, we present the case of a patient with diploic arteriovenous fistulas with marked cortical venous reflux and a literature review. A 73-year-old woman presented with headache. Magnetic resonance angiography revealed abnormal signal intensity in the diploic layer of the left frontal bone. Digital subtraction angiography demonstrated a diploic arteriovenous fistulas located in the left frontal bone. The arteriovenous fistulas were fed by multiple branches of the left external carotid artery, mainly from the middle meningeal artery, branches of the ophthalmic artery, and the inferolateral trunk. The fistulas drained into the cerebral cortical veins surrounding the frontal lobe via an emissary vein of the frontal bone. With the femoral arterial approach, transarterial catheterization into the shunted diploic vein was performed with a small tapered microcatheter, and the arteriovenous fistulas were completely embolized with N-butyl-2-cyanoacrylate. The patient was discharged without complications. No recurrent arteriovenous fistulas were observed during the 12-month follow-up period. Endovascular treatment is an effective technique for the curative treatment of diploic arteriovenous fistulas.

Direct Carotid Cavernous Fistulas.

A direct carotid cavernous fistula (CCF) is an abnormal shunt between the internal carotid artery (ICA) and the cavernous sinus (CS). Traumatic CCF is the most common type, accounting for up to 75% of all CCFs. For the management of direct CCF, endovascular therapy has become the standard. For successful endovascular therapy, evaluation of the size and location of orifice of the CCF, venous drainage, and tolerance for ICA occlusion on cerebral angiography is necessary. Multi-planner reformatted images of 3D rotation angiography are useful to visualize the fistula and compartments of the CS precisely. Due to the limited commercial availability of detachable balloons, detachable coils have become a widely employed endovascular tool for the treatment of direct CCFs. The advantageous aspects of coil application are their easy retrievability and better control. In the case of large/multiple fistulas, adjunctive techniques, including balloon- and stent-assisted techniques, are often needed to occlude the CCF while preserving the ICA. To avoid cranial nerve palsy related to over-packing of the CS with detachable coils or a detachable balloon, selective embolization of the fistula portion is required. Use of liquid embolic materials and covered stents was recently reported as another adjunctive technique. In cases in which it is impossible to occlude the CCF while preserving the ICA, parent artery occlusion (PAO) is considered. The selection of additional/alternative techniques and devices depends on the anatomy and hemodynamics of each CCF, and the skill and experience of individual operators.

Basal cerebral venous drainage from cavernous sinus dural arteriovenous fistulas.

INTRODUCTION: This study aimed to define the patterns of basal cerebral venous drainage (BCVD) from cavernous sinus dural arteriovenous fistulas (CSDAVFs). MATERIALS AND METHODS: Forty sets of selective angiographic data from 36 patients with spontaneous CSDAVFs (age range, 53-79 years) were retrospectively analyzed for their drainage patterns. Three types of BCVD were observed, i.e., superolateral type, BCVD via the deep middle cerebral vein or uncal vein; posterolateral type, BCVD via the superior petrosal sinus and petrosal vein; and posteromedial type, BCVD via the bridging vein and the anterior pontomesencephalic vein. MR images and/or 3D-DSA images were also reviewed when available. RESULTS: BCVD from CSDAVF was found in 12 patients (30%), and the other drainage routes included the superior ophthalmic vein in 25 (63%), the inferior petrosal sinus in 17 (43%), the superficial middle cerebral vein in 17 (43%), intercavernous sinus in 15 (38%), the superior petrosal sinus in seven (18%), and pterygoid plexus in two (5%), respectively. In 12 patients with BCVD, superolateral type was found in four (33%), posterolateral type in five (42%), and posteromedial type in seven (58%). Four cases of posteromedial type were associated with other types of BCVD. CONCLUSION: CSDAVFs are often associated with BCVD via three different pathways. The posteromedial type via the bridging vein is the most frequent type of BCVD.

The anterior medullary-anterior pontomesencephalic venous system and its bridging veins communicating to the dural sinuses: normal anatomy and drainage routes from dural arteriovenous fistulas.

INTRODUCTION: We evaluated the normal venous anatomy of the anterior medullary/anterior pontomesencephalic venous (AMV/APMV) system and bridging veins connected to the dural sinuses using magnetic resonance (MR) imaging and demonstrated cases of dural arteriovenous fistulas (DAVFs) with bridging venous drainage. MATERIALS AND METHODS: MR images obtained using a 3D gradient echo sequence in 70 patients without lesions affecting the deep or posterior venous channels were reviewed to evaluate the normal anatomy of the AMV/APMV system and bridging veins. MR images and digital subtraction angiography in 80 cases with intracranial or craniocervical junction DAVFs were reviewed to evaluate the bridging venous drainage from DAVFs. RESULTS: MR images clearly revealed AMV/APMV in 35 cases. Fifteen cases showed a direct connection between AMV and APMV, while 15 cases showed an indirect communication via the transverse pontine vein or the bridging vein. In the five remaining cases, the AMV and APMV end separately to the bridging vein or the transverse pontine vein. Bridging veins were identified in 34 cases, connecting to the cavernous sinus in 33, to the suboccipital cavernous sinus in 11, and the inferior petrosal sinus in five cases. In 80 DAVF cases, seven of 40 cavernous sinus DAVFs, two craniocervical junction DAVFs, and one inferior petrosal sinus DAVF drained via bridging veins to the brain stem. CONCLUSION: The AMV/APMV and bridging veins showed various anatomies and frequently showed a connection to the cavernous sinus. Knowledge of the venous anatomy is helpful for the diagnosis and intravascular treatment of DAVFs.

Unique infiltrating morphology of a meningioma-a case report.

BACKGROUND: We report on the case of a patient with meningioma that was correctly identified through biopsy. CASE DESCRIPTION: A 69-year-old woman presented with slight headache and was then examined at our hospital. Neurologic and physical examinations found no abnormality. Magnetic resonance imaging demonstrated a well-enhanced huge, dural-based, and plaque-like mass extending throughout the parietooccipital convexity and the posterior fossa. Tumors pressed the adjacent brain cortex while extending along the Virchow-Robin space. A CT scan also showed hyperostosis on the parietooccipital bone. Angiography demonstrated a vascular blush that appeared to be of a tumor-like shape. A biopsy was performed to confirm the diagnosis. The histologic findings demonstrated meningothelial meningioma with infiltration into the Virchow-Robin space. CONCLUSIONS: Many radiographic patterns of meningioma have been reported, but the present case is quite rare. The radiographic and pathologic findings in our patient are discussed.

Shapability, memory, and luminal changes in microcatheters after steam shaping: a comparison of 11 different microcatheters.

PURPOSE: The purpose of this study was to compare the characteristics of shaped microcatheters, including shapability, durability, and luminal changes. MATERIALS AND METHODS: Eleven brands of steam-shaped microcatheters and one brand of preshaped microcatheter were evaluated. There were 2 nonreinforced and 10 reinforced devices supported by coils. For evaluation of shapability, the tip angle of 6 samples of each brand were measured after steam-shaping for 20 seconds with a shaping mandrel bent at a 90 degrees or 150 degrees angle. The ability to maintain the shaped angle after guidewire insertion stress (durability) was compared by calculation of the change in the tip angle by using 3 samples of each brand. Luminal change after steam shaping was evaluated by calculation of narrowing rate of the smallest diameter and observation of the surface morphology of the mold of each catheter lumen by using a silicone polymer by means of a fluorescent projection method. RESULTS: The nonreinforced microcatheters and the fiber-braided microcatheter showed higher shapability than the others. The degree of distal microcatheter straightening with the microguidewire insertion was less pronounced in the preshaped microcatheter and the fiber-braided microcatheter. Spontaneous recovery to the initial tip angle 5 minutes after the guidewire procedure was observed in 10 brands to various degrees (87%-98%). Irregular luminal surface morphology at the angled portion was found in 6 reinforced brands. One nonreinforced catheter and the fiber-braided catheter showed high narrowing rates >6%. CONCLUSION: There are differences in shapabilty, durability, and luminal changes of steam shaping in 12 brands of microcatheters. These characteristics could be important factors in catheter choice for endovascular procedures.

Limitations of three-dimensional reconstructed computerized tomography angiography after clip placement for intracranial aneurysms.

OBJECT: The authors compared the usefulness of three-dimensional (3D) reconstructed computerized tomography (CT) angiography with 3D digital subtraction (DS) angiography in assessing intracranial aneurysms after clip placement. A retrospective review of clinical cases was performed. METHODS: Between May 2001 and May 2003, 17 patients with a total of 20 intracranial aneurysms underwent 3D CT and 3D DS angiography following clip placement. The authors assessed the presence or absence of residual aneurysm necks and stenoocclusive changes in the parent artery and the neighboring artery. The efficacy of CT angiographic visualization was also evaluated. In 12 of the 20 aneurysms, both 3D modalities similarly demonstrated the residual aneurysm neck and stenoocclusive changes in the parent artery and neighboring artery. Three-dimensional CT angiography failed to demonstrate three of the aneurysms, and the studies were not considered suitable for evaluation because of the presence of metallic artifacts. In the remaining five studies, the 3D CT angiograms did not effectively demonstrate the neighboring and parent arteries. The detectability of residual aneurysm necks was correlated with the clip material and with the number of clips applied. CONCLUSIONS: Three-dimensional DS angiography is still necessary in cases involving multiple clips or with cobalt alloy clips because the clips appear as metal artifacts on 3D CT angiography.

Anatomic features predictive of complete aneurysm occlusion can be determined with three-dimensional digital subtraction angiography.

BACKGROUND AND PURPOSE: Complete occlusion of intracranial aneurysms is the goal of endovascular treatment and is influenced by several aneurysm-related anatomic factors. The anatomic features of aneurysms can be characterized by three-dimensional reconstructed images by use of rotational digital subtraction angiography (3D-DSA). The purpose of this study was to determine the anatomic factors that could help predict complete endosaccular packing of cerebral aneurysms by use of 3D-DSA and to design a simple scoring system to predict the difficulty of achieving complete occlusion of the aneurysm. METHODS: Forty-seven patients with 47 intracranial berry (<12 mm) aneurysms underwent 3D-DSA. Aneurysms were subsequently treated by endosaccular packing with coils. The following aneurysm-related anatomic parameters were measured on 3D-DSA images: largest diameter, neck size, dome-to-neck ratio, shape, and relationship to the neighboring artery. The relationship between each parameter and the rate of successful treatment was determined, and a score used to rate difficulty of attaining occlusion (ie, difficulty score) was developed on the basis of the identified predictors of successful treatment. Subsequently, we assessed the correlation between the score and the rate of successful occlusion. RESULTS: Four anatomic parameters correlated significantly with the rate of successful occlusion: neck size (P =.014), shape (P=.042), dome-to-neck ratio (P <.01), and relationship to neighboring artery (P=.025). The difficulty score based on two parameters (dome-to-neck ratio and relationship to neighboring artery) significantly correlated with the occlusion rate (r = 0.63, P <.01). CONCLUSION: In this population, the difficulty score based on 3D-DSA findings provides useful information for prediction of successful endovascular treatment for intracranial aneurysms.

Treatment of intracranial dural arteriovenous fistulas: current strategies based on location and hemodynamics, and alternative techniques of transcatheter embolization.

Intracranial dural arteriovenous fistulas (AVFs) can occur anywhere within the dura mater. Patients may be clinically asymptomatic or may experience symptoms ranging from mild symptoms to fatal hemorrhage, depending on the location (eg, cavernous sinus, transverse-sigmoid sinus, tentorium, superior sagittal sinus, anterior fossa) and venous drainage pattern of the AVF. In the past, dural AVFs have been treated with a variety of approaches, including surgical resection, venous clipping, transcatheter embolization, radiation therapy, or a combination of these treatments. Recent developments in catheter intervention now allow most patients to be cured with transcatheter embolization, although stereotactic radiation therapy is demonstrating good results in an increasing number of cases and surgery is still the preferred option in some cases. Familiarity with drainage patterns, the risk of aggressive symptoms, recent technical advances, and current treatment strategies is essential for the treatment of intracranial dural AVFs.

Transcatheter obliteration of gastric varices. Part 1. Anatomic classification.

Since its introduction in the mid-1990s, balloon-occluded retrograde transvenous obliteration (BRTO) has become widely accepted in Japan as a minimally invasive, highly effective treatment for gastric varices. Sufficient filling and stagnation of the sclerosing agent in the entire variceal complex is essential for successful BRTO of gastric varices. However, the success of BRTO in this context also requires familiarity with the hemodynamic features of the varices, including the patterns of their afferent and draining veins, which affect the degree of difficulty in performing BRTO. Thus, accurate assessment of the hemodynamic pattern before and during each procedure is essential for successful treatment. Sixty cases of gastric varices that were successfully treated with transcatheter techniques over the past 5 years were reviewed and analyzed. From this study, a classification system for gastric varices was developed that is based on the hemodynamic pattern of the varices.

Transcatheter obliteration of gastric varices: Part 2. Strategy and techniques based on hemodynamic features.

Balloon-occluded retrograde transvenous obliteration (BRTO) has become the treatment of choice for gastric varices at many institutions in Japan. However, in some cases that involve complex types of afferent or draining veins, the use of standard BRTO for the treatment of gastric varices may be associated with several difficulties that can lead to unfavorable results. In such cases, additional techniques are required for successful treatment. These techniques include stepwise injection of the sclerosing agent, selective injection of the agent via a microcatheter, coil embolization of the afferent gastric veins, double-balloon catheterization, and BRTO performed with percutaneous transhepatic portal venous access or transileocolic venous access. The majority of gastric varices can be treated successfully with a combination of these techniques. However, accurate assessment of the variceal hemodynamic pattern is the most important factor in ensuring successful treatment.