Toshinori Matsushige

Cerebral sinovenous thrombosis after closed head injury.

BACKGROUND Cerebral sinovenous thrombosis (CSVT) after closed head injury is an uncommon but potentially serious complication. The aim of this study was to determine whether diffusion weighted imaging (DWI) provide predictive information regarding prognosis. METHODS We retrospectively reviewed a series of 11 patients with CSVT after closed head injury. Each patient underwent computed tomography and magnetic resonance imaging within 24 hours of onset of symptoms, including DWI, magnetic resonance venography, and conventional sequences. Apparent diffusion coefficient (ADC) values were measured in seven regions of interest in 7 of 11 patients using DWI. Follow-up imaging and clinical outcome were assessed 6 months or later after initial presentation. RESULTS The most affected sinus was the posterior portion of the superior sagittal sinus. There was a mean time interval of 4.1 days between subsequent venous stroke and the initial insult. Brain edema improved in 6 of 11 patients on follow-up imaging. Six of 11 patients recovered successfully, although high or mixed DWI intensity associated with moderately decreased ADC (0.53-0.57 x 10(-3) mm2/s). Two other patients with hematomas developed venous infarction, despite mixed DWI with heterogeneous ADC value (0.55-1.11 x 10(-3) mm2/s). The other three patients, with high DWI and strongly decreased ADC values (0.26-0.27 x 10(-3) mm2/s), developed severe brain atrophy after superior sagittal sinus thrombosis. CONCLUSIONS The prospective cutoff point of ADC value may be higher in CSVT after head injury with traumatic hematoma. The territory of venous infarction was found to be larger in infants after treatment failure. In infants, CSVT can demonstrate initially cytotoxic brain edema, which is reversible with anticoagulation therapy.

Bilateral vertebral artery dissecting aneurysm with subarachnoid hemorrhage treated with staged bilateral vertebral artery coil occlusion: a case report

BACKGROUND Vertebral artery dissecting aneurysm is now increasingly recognized as a cause of posterior circulation stroke in young adults. Here, we report a case of bilateral VADA with SAH, treated by bilateral coil occlusion using GDCs. CASE DESCRIPTION A 64-year-old woman was admitted to our hospital with consciousness disturbance (Hunt and Kosnik: grade 4). Computed tomography showed diffuse SAH with a thick hematoma in the left C-P angle. Magnetic resonance angiography, 3D-CTA, and cerebral angiography revealed bilateral VADAs. First, the ruptured left VADA involving the PICA and a perforating branch was treated by occluding the lower half of the VADA and the proximal VA with GDCs in the acute stage. Thereafter, the residual VADA and contralateral VADA exhibited enlargement on cerebral angiography and MRA for 2 months after the initial surgery; thus, the right VADA was occluded by GDCs just proximal to the right PICA after confirming BTO tolerance. CONCLUSION Staged bilateral VA coil occlusions combined with BTO may be one of the treatment strategies for bilateral VADA with SAH in cases presenting surgical difficulty due to anatomical factors or severe grade of SAH.

Superselective Shunt Occlusion for the Treatment of Cavernous Sinus Dural Arteriovenous Fistulae

BACKGROUND: In treating cavernous sinus dural arteriovenous fistulae (CSdAVFs), transvenous embolization of the whole affected sinus is usually performed, which may result in the disturbance of normal venous drainage or permanent cranial nerve palsy. OBJECTIVE: To describe superselective shunt occlusion of CSdAVFs. METHODS: Between July 2005 and August 2011, we had 20 consecutive cases of CSdAVFs. In 14 cases (70%), we could detect the restricted locus of arteriovenous shunts by 3-dimensional rotational angiography and/or superselective arteriography. After navigating the microcatheter to the shunt segment, consecutive superselective arteriovenography was performed to confirm the location of the microcatheter at the proper position. RESULTS: In 12 of 14 cases (85.7%) in which the shunt was restricted, coiling only in the small venous pouch or compartment, which was just downstream of the shunt point, led to complete disappearance of the shunt without obliterating the entire sinus. No recurrence or permanent cranial nerve palsy was observed during the follow-up period with a mean of 46 months (range, 3-69 months) in 12 cases treated by superselective shunt occlusion. CONCLUSION: This technique, which enables complete extirpation of shunts by small amounts of coils, is a feasible way to treat CSdAVFs with excellent mid- to long-term results. Understanding of the angioarchitecture by 3-dimensional rotational angiography and consecutive superselective arteriovenography was useful. This method should be considered before sinus packing or mere obliteration of dangerous venous outlets. ABBREVIATIONS: AVF, arteriovenous fistula CNP, cranial nerve palsy CS, cavernous sinus CSdAVF, cavernous sinus dural arteriovenous fistula ECA, external carotid artery 3-D RA, 3-dimensional rotational angiography SSSO, superselective shunt occlusion

Hybrid operating room for the treatment of complex neurovascular and brachiocephalic lesions

BACKGROUND We examine the impact of the installation of integrated hybrid operating rooms (ORs) that allow both surgical and endovascular procedures and are designed for less invasive and 1-stage treatment of complex neurovascular lesions. METHODS We retrospectively analyzed our experience in the treatment of complex neurovascular lesions in a hybrid OR. RESULTS Three patients with distal middle cerebral artery (MCA) aneurysms underwent a proximal clip occlusion or endovascular trapping with a superficial temporal artery-MCA bypass after correct localization of the recipient branch distal to the aneurysm using superselective intra-arterial infusion of indocyanine green under an operating microscope. Two patients with innominate artery stenosis were treated with retrograde stenting from the common carotid artery (CCA) with distal protection of the internal carotid artery (ICA) alone, and with antegrade stenting with dual protection of the ipsilateral ICA and the vertebral artery. Two patients with tandem stenosis of the proximal CCA and carotid bifurcation underwent 1-stage retrograde stenting combined with a carotid endarterectomy. A patient with the innominate artery and the proximal CCA stenosis underwent staged percutaneous antegrade angioplasty of the innominate artery followed by retrograde stenting of both lesions. A patient with tandem stenosis of the subclavian and innominate arteries underwent 1-stage retrograde stenting. In 2 patients with carotid stenosis that was difficult to access via the endovascular route, carotid stenting was performed by direct puncture of the proximal CCA. No patients suffered from new postoperative neurologic deficits. CONCLUSIONS The integration of a high-end hybrid OR enables combined endovascular and surgical procedures for complex neurovascular and brachiocephalic lesions in a 1-stage treatment.

Giant cell tumor of the temporal bone with intratumoral hemorrhage.

We report a case of hemorrhagic giant cell tumor (GCT) of the temporal bone in a 77-year-old woman. The patient suffered from sudden-onset headache and vomiting associated with left temporal hemorrhage. MRI revealed a left temporal extradural mass lesion expanding to the subtemporal fossa, showing strong hypointensity on T(2)-weighted imaging. Subsequent MRI revealed tumor growth with multiple cystic components at 1-month follow up. The tumor was found to be a GCT associated with recent intratumoral hemorrhage and abundant hemosiderin pigmentation. T(2)-weighted MRI of the GCT strongly supported hemosiderin deposition. Secondary formation of cystic components in the GCT can also reflect prior hemorrhage and indicate the progression of shape modification. A literature review revealed that hemosiderin deposition in this rare entity is not as rare as previously thought and that massive intratumoral hemorrhage may occur.

Ventricular Microaneurysms in Moyamoya Angiopathy Visualized with 7T MR Angiography

SUMMARY: The pathophysiologic role of hemodynamic alteration to peripheral vessels in Moyamoya angiopathy and the formation of microaneurysms remains unclear. The purpose of this study was to investigate microaneurysms in collateral Moyamoya vessels by using 7T ultra-high-field MR imaging. Ten patients with Moyamoya disease were evaluated with TOF-MRA at 7T acquired with 0.22 × 0.22 × 0.41 mm3 resolution. In 10 patients, 4 microaneuryms located in the ventricles were delineated. The mean diameters of collateral vessels and microaneurysms arising from those vessels were 0.87 mm (range, 0.79–1.07 mm) and 0.80 mm (range, 0.56–0.96 mm), respectively. In 1 case with follow-up scans 6 months after a direct extracranial-intracranial bypass operation, the microaneurysm disappeared. Ventricular microaneurysms in Moyamoya angiopathy collateral vessels, inaccessible by conventional imaging techniques, can be detected by 7T TOF-MRA.

Single-stage operation for a giant haemangiopericytoma following intracranial feeder embolization

Meningeal haemangiopericytomas (HPC) are malignant intracranial neoplasms that commonly recur and metastasize. Large size at diagnosis, abundant intracranial feeders and the risk of intraoperative bleeding can make them difficult to completely remove in one operation. We report here a rare case of a giant HPC which was treated successfully using a one-stage operation following superselective intracranial feeder occlusion. A 30-year-old man presented with a left middle cranial fossa tumour extending to the left temporal lobe and cerebellar tentorium. Angiography revealed supply from a dilated left posterior temporal artery branching from the posterior cerebral artery. The tumour was totally removed in a single-stage excision after embolization of the intracranial major feeding artery. The present case suggests the usefulness of preoperative embolization for HPC, particularly of intracranial feeders, to achieve total resection safely in a single operation.

Correlation of the venous angioarchitecture of multiple cerebral cavernous malformations with familial or sporadic disease: a susceptibility-weighted imaging study with 7-Tesla MRI

OBJECTIVE Multiple cerebral cavernous malformations (CCMs) are rare lesions that occur in sporadic or familial form. Depending on the disease form, the natural history and treatment of the lesions strongly vary. Molecular analysis of an underlying germline mutation (CCM1-3) is the most sensitive screening method to distinguish between sporadic and familial cases. However, based on the different pathomechanisms that are believed to be involved in either form, significant distinctions in the CCM-associated cerebral venous angioarchitecture should be detectable. This has not been systematically studied. METHODS A consecutive series of 28 patients with multiple CCMs (681 total) diagnosed on 1.5-T MRI underwent genetic screening for CCM1-3 mutations and high-resolution susceptibility-weighted imaging (SWI) of the cerebral venous angioarchitecture with 7-T MRI. Imaging data were analyzed to examine the CCM-associated venous angioarchitecture. Results were correlated with findings of molecular analysis for CCM1-3 mutations. RESULTS Two different SWI patterns (sporadic and familial) were found. The presence of associated developmental venous anomalies correlated with negative screening for germline mutations (11 sporadic) in all cases. All patients with confirmed familial disease showed normal underlying venous angioarchitecture. Additionally, a very unusual case of a probable somatic mutation is presented. CONCLUSIONS The SWI results of the venous angioarchitecture of multiple CCMs correlate with sporadic or familial disease. These results are consistent with the theory that venous anomalies are causative for the sporadic form of multiple CCMs.

Giant Intracranial Aneurysms at 7T MRI

Seven giant intracranial aneurysms were evaluated, and 2 aneurysms were available for histopathologic examination. Aneurysm walls were depicted as hypointense in TOF-MRA and SWI sequences with excellent contrast ratios to adjacent brain parenchyma. A triple-layered microstructure of the aneurysm walls was visualized in all aneurysms in TOF-MRA and SWI. This could be related to iron deposition in the wall, and similar findings were seen in 2 available histopathologic specimens. In vivo 7T TOF-MRA and SWI can delineate the aneurysm wall and the triple-layered wall microstructure in giant intracranial aneurysms. SUMMARY: Giant intracranial aneurysms are rare vascular pathologies associated with high morbidity and mortality. The purpose of this in vivo study was to assess giant intracranial aneurysms and their wall microstructure by 7T MR imaging, previously only visualized in histopathologic examinations. Seven giant intracranial aneurysms were evaluated, and 2 aneurysms were available for histopathologic examination. Six of 7 (85.7%) showed intraluminal thrombus of various sizes. Aneurysm walls were depicted as hypointense in TOF-MRA and SWI sequences with excellent contrast ratios to adjacent brain parenchyma (range, 0.01–0.60 and 0.58–0.96, respectively). The triple-layered microstructure of the aneurysm walls was visualized in all aneurysms in TOF-MRA and SWI. This could be related to iron deposition in the wall, similar to the findings in 2 available histopathologic specimens. In vivo 7T TOF-MRA and SWI can delineate the aneurysm wall and the triple-layered wall microstructure in giant intracranial aneurysms.

Vascular Wall Imaging of Unruptured Cerebral Aneurysms with a Hybrid of Opposite-Contrast MR Angiography

BACKGROUND AND PURPOSE: Inflammation and degeneration of the intracranial saccular aneurysm wall play a major role in aneurysm formation, development and subsequent rupture. The aim of this study was to characterize the walls of unruptured intracranial aneurysms by using a hybrid of opposite-contrast MRA at 3T. MATERIALS AND METHODS: Fourteen consecutive patients with 17 unruptured intracranial aneurysms who initially underwent clipping surgery were prospectively evaluated. All aneurysms were scanned preoperatively by using a hybrid of opposite-contrast MRA in 3T high-resolution MR imaging. We classified intraoperative findings of atherosclerotic plaques in the aneurysms into 3 grades: grade A (major plaques), grade B (minor plaques), and grade C (no plaques). The contrast ratio of the high-intensity area was also measured relative to the background low-intensity area inside the carotid artery. RESULTS: Findings from preoperative plaque imaging of the aneurysm corresponded to the intraoperative findings in 15 of 16 aneurysms (excluding 1 that was impossible to visualize in its entirety due to anatomic reasons). Overall sensitivity and specificity of the hybrid of opposite-contrast MRA were 88.9% and 100%, respectively. During the operation, 4 aneurysms were classified as grade A; 5, as grade B; and 7, as grade C. The means of the contrast ratio for grades A, B, and C were 0.72 ± 0.03, 0.34 ± 0.30, and −0.02 ± 0.09, respectively. CONCLUSIONS: The hybrid of opposite-contrast MRA can detect visible atherosclerotic plaques in the unruptured aneurysm wall, and the contrast ratio in intracranial aneurysms correlated with their presence and extent. A study including a larger series is needed to validate the diagnostic potential of this imaging technique.