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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.

On angiography, two types of intrahepatic portosystemic venous shunt were seen: intrahepatic portal venous-hepatic venous communication and intrahepatic portal venous-perihepatic venous communication. Transcatheter embolization is effective for treatment of intrahepatic portosystemic venous shunt. Retrograde transcaval obliteration is the least invasive technique and is recommended as the first choice for treatment of portosystemic venous shunt except in patients with multiple shunts.

ABSTRACT. The aim of this study was to evaluate the anatomy of and normal variations in the craniocervical junction veins. We retrospectively reviewed 50 patients who underwent contrast-enhanced CT with a multidetector scanner. Axial and reconstructed images were evaluated by two neuroradiologists with special attention being paid to the existence and size of veins and their relationships with other venous branches around the craniocervical junction. The venous structures contributing to craniocervical junction venous drainage, including the inferior petrosal sinus (IPS), transverse-sigmoid sinus, jugular vein, condylar vein, marginal sinus and suboccipital cavernous sinus were well depicted in all cases. The occipital sinus (OS) was identified in 18 cases, including 4 cases of prominent-type OS. The IPS showed variations in drainage to the jugular vein through the jugular foramen or intraosseous course of occipital bone via the petroclival fissure. In all cases, the anterior condylar veins connected the anterior condylar confluence to the marginal sinus; however, a number of cases with asymmetry and agenesis in the posterior and lateral condylar veins were seen. The posterior condylar vein connected the suboccipital cavernous sinus to the sigmoid sinus or anterior condylar confluence. The posterior condylar canal in the occipital bone showed some differences, which were accompanied by variations in the posterior condylar veins. In conclusion, there are some anatomical variations in the venous structures of the craniocervical junction; knowledge of these differences is important for the diagnosis and treatment of skull base diseases. Contrast-enhanced CT using a multidetector scanner is useful for evaluating venous structures in the craniocervical junction. Intracranial veins and venous sinuses converge to form major dural sinuses, the transverse sinus and the sigmoid sinus, which drain into extracranial veins. These major dural sinuses are connected by other venous structures at the skull base. These venous structures form complex venous networks that drain intracranial venous flow into extracranial veins at the craniocervical junction [1]. These venous structures are also known to have an important role as collateral pathways in cases of venoocclusive disease. The typical relationships between the craniocervical junction veins are shown in Figure 1. Knowledge of the anatomical relationships and variations of these veins is necessary not only for radiological diagnosis, but also when considering surgical or endovascular treatment of skull base diseases. Some investigators have previously reported the anatomy of and variations in these veins using anatomical and radiological methods with conventional angiography or contrast-enhanced MRI [2][3][4][5][6][7][8]. CT has been recognised as inadequate for evaluations of the posterior fossa owing to artefacts from bony structures; however, recent applications of multidetector row CT (MDCT) enable us to evaluate the posterior fossa with thin-sectional axial images and/o...

IntroductionSpinal 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.MethodsWe 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.ResultsThe 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.ConclusionIn 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.

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.

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.

Dilatation of peripancreatic veins with nonvisualization of inferior peripancreatic veins suggests tumor invasion of peripancreatic tissue.