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Shunji Matsubara

Publications and source records attributed to Shunji Matsubara.

11 recordsLinked to original sources
PubMed2006

Microcatheter pull-up technique in the transvenous embolization of an isolated sinus dural arteriovenous fistula. Technical note.

The authors describe a novel technique involving the use of a gooseneck snare for microcatheterization of isolated sinus dural arteriovenous fistulas (DAVFs). In some patients the inferior petrosal and transverse-sigmoid sinuses, the route of transvenous embolization (TVE) for DAVF, are separated by several channels. Even if a guidewire can be passed over the occluded portion and the affected sinus can be accessed, one may not necessarily be able to insert a microcatheter. The authors report on three patients who underwent successful microcatheterization via a novel pull-up technique, which makes use of a gooseneck snare to perform TVE even in very difficult circumstances.

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PubMed2005

Angiographic changes in venous drainage of cavernous sinus dural arteriovenous fistulae after palliative transarterial embolization or observational management: a proposed stage classification.

OBJECTIVE: We assessed whether angiographic changes in venous drainage patterns occur over time in cavernous sinus dural arteriovenous fistulae (dAVFs) without a complete cure. METHODS: We classified 65 cavernous sinus dAVFs into three types on the basis of initial angiographic findings. In Type 1, both anterior and posterior drainage routes were open; in Type 2, the posterior drainage route was closed, whereas the anterior drainage route was open; and in Type 3, both the posterior and anterior drainage routes were closed. RESULTS: Of the 65 dAVFs, 40 were of Type 1, 21 of Type 2, and 4 of Type 3. During the follow-up period, 17 of the dAVFs that were treated palliatively with transarterial embolization (n = 11) or monitored without therapy (n = 6) demonstrated angiographic changes. In these 11 patients, there was a change in the venous drainage pattern from Type 1 to Type 2 (n = 5), from Type 2 to Type 3 (n = 3), and from Type 1 to Type 3 (n = 3). One of 11 had a conversion into a lesion with cortical venous drainage. The remaining 6 dAVFs (4 with observational management, 2 with transarterial embolization) demonstrated closure of the fistula; in 5 of these, the affected cavernous sinus was not depicted on follow-up angiograms. CONCLUSION: In some cavernous sinus dAVFs with palliative transarterial embolization or observational management, there was a change in the venous drainage patterns, consisting of a decrease in the number of venous drainage routes. There was a trend for the posterior route to close before the anterior drainage or cortical drainage route. This suggests the occurrence of a staged progression in a regular direction in cavernous sinus dAVFs. Without treatment aiming at a complete cure, most cavernous sinus dAVFs can behave benignly, with a low possibility of development of cortical venous reflux during follow-up.

Adult↗
PubMed2005

Evaluation of aneurysm stability after endovascular embolization with Guglielmi detachable coils: correlation between long-term stability and volume embolization ratio.

The correlation between volume embolization ratio (VER), the percentage of aneurysm volume occupied by coils, and aneurysm stability after endovascular treatment with platinum coils was studied in 86 patients who underwent embolization of 88 cerebral saccular aneurysms with standard platinum coils between March 1997 and January 2003. Radiographic follow up was possible of 62 aneurysms with greater than 70% obliteration on immediate post-procedure angiograms for more than 6 months. Immediate post-procedure evaluation found that 12 of 14 small (<4 mm), 12 of 38 medium (4-<10 mm), and two of 10 large (> or =10 mm) aneurysms had high (> or =25%) VER. In addition, the VER was high in 22 of 40 aneurysms with small (<4 mm) and four of 22 with wide necks (> or =4 mm). Evaluation of 57 aneurysms at 6 months after coil embolization found recanalization in two of 25 aneurysms with high VER and 21 of 32 with low (<25%) VER, indicating that aneurysms with high VER are significantly more stable than those with low VER (p < 0.01). VER strongly affects aneurysm stability, so high VER is desirable and a useful predictor of aneurysm stability.

Adult↗
PubMed2004

Ruptured de novo thrombotic giant aneurysm induced by ethyl 2-cyanoacrylate: case report.

BACKGROUND: A very rare case of a ruptured aneurysm induced by ethyl 2-cyanoacrylate is reported. CASE DESCRIPTION: Six years earlier, this 68-year-old woman had undergone microvascular decompression for trigeminal neuralgia during which the left vertebral artery, which compressed the exit zone of the trigeminal nerve, had been detached and fixed to the dura mater of the petrous bone with ethyl 2-cyanoacrylate. Shortly thereafter she underwent microvascular decompression for left-side facial palsy; again ethyl 2-cyanoacrylate was used. Six years later, she suffered a subarachnoid hemorrhage because of rupture of a new aneurysm of the left vertebral artery. She was referred to our hospital where coil embolization was attempted on the day following the insult. However, the left vertebral artery and the aneurysm could not be occluded completely, and she suddenly died 20 days later from rerupture of the aneurysm. CONCLUSION: This is the first pathologic report of a ruptured de novo aneurysm induced by ethyl 2-cyanoacrylate. We suggest that arterial wall damage by ethyl 2-cyanoacrylate may have contributed to the development of the de novo aneurysm.

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PubMed2004

Does multimodality therapy of arteriovenous malformations improve patient outcome?

The strategy for treating arteriovenous malformations (AVMs) has undergone changes and long-term follow-up results remain unclear. To compare the outcomes of different treatment strategies, we divided 112 patients with 113 AVMs into groups with hemorrhagic (n = 71, 62.8%) and nonhemorrhagic (n = 42, 37.2%) AVMs and subdivided these according to the period in which they were treated (before/after 1990). In the more recent period, treatment more frequently involved the use of the gamma-knife and microembolization to the AVM as well as combination therapy. Long-term follow-up showed that the complication rate was lower and the Rankin scale better, in the more recently treated group. Based on our findings we suggest that AVMs should be treated aggressively using a multimodality strategy.

Adolescent↗
PubMed2004

Detection of enlarged cortical vein by magnetic resonance imaging contributes to early diagnosis and better outcome for patients with anterior cranial fossa dural arteriovenous fistula.

Twelve patients (10 men, 2 women) with anterior cranial fossa dural arteriovenous fistula (AVF) were treated at our institute between January 1976 and March 2002. Intracranial hemorrhage was the presenting symptom in six patients. Magnetic resonance (MR) imaging findings identified abnormal cortical veins as flow voids in four of five patients. Angiography was the basis of the diagnosis in all patients. Surgery was the primary treatment in nine patients. The other three patients refused intervention and managed conservatively. Surgical morbidity was negligible and the treatment outcome was highly dependent on the clinical status at presentation. In contrast to the reported high incidence of intracranial hemorrhage in patients with dural AVF in the anterior cranial fossa, only half of our study population presented with hemorrhage. Enlarged cortical veins in the frontobasal area could be detected as flow voids on MR images. This finding contributed to the early diagnosis and treatment of patients treated at our institution for dural AVF in the anterior cranial fossa, and to the better outcomes we obtained in these patients.

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PubMed2004

Ischemic basilar artery dissecting aneurysm treated by stenting only--case report.

A 45-year-old man presented with enlargement of basilar artery dissecting aneurysm 10 months after suffering brain stem infarction. Combined stenting and placement of Guglielmi detachable coils (GDCs) was planned to obliterate the aneurysm sac. Stent deployment was performed but the procedure was halted to avoid overdosing with contrast material. Cerebral angiography 10 days later showed thrombosis of the aneurysm sac and normalization of the blood flow in the basilar artery. The patient has been followed up for 2 years and showed good clinical and angiographic outcome. Stenting results in obliteration of the aneurysm sac, so a two-stage procedure is recommended.

Aortic Dissection↗
PubMed2004

Incidence and risk factors for the growth of unruptured cerebral aneurysms: observation using serial computerized tomography angiography.

OBJECT: The goal of this study was to examine the growth of unruptured intracranial aneurysms with the focus on the risk factors and incidence of these lesions. METHODS: One hundred sixty-six untreated cerebral saccular aneurysms were analyzed in 140 patients. The age of the patients ranged from 29 to 82 years (mean 62.8 years), the female/male ratio was 94:46, and the mean follow-up period was 17.7 months. Aneurysms were located at the internal carotid artery (ICA) in 68 patients, the middle cerebral artery (MCA) in 43, the anterior cerebral artery in 38, the basilar artery (BA) in 13, and the vertebral artery in four patients. The maximum diameter of the lesions ranged from 2 to 20 mm (mean 4.1 mm). All patients were examined using serial computerized tomography angiography to evaluate signs of aneurysm growth. Although growth was identified in 10 aneurysms (nine patients 16.4%]), no bleeding occurred. Growth-related changes were significantly associated with the size of the aneurysm and occurred in three (2.4%) of 125 aneurysms measuring 2 to 4 mm, three (9.1%) of 33 lesions measuring 5 to 9 mm, and four (50%) of eight lesions measuring 10 to 20 mm. These changes were more frequently found in aneurysms located at the BA bifurcation (two [40%] of five lesions) and the ICA (six [8.8%] of 68 lesions) than in those located at the MCA (zero of 43 lesions, p < 0.05). The 1-, 2-, and 3-year cumulative growth rates calculated using the Kaplan-Meier method were 2.5, 8, and 17.6%, respectively. CONCLUSIONS: A diameter of at least 10 mm and a location at the BA bifurcation or the ICA were significant risk factors for aneurysm growth. The incidence of growth was 2.5% in the 1st year and this risk increased yearly. Computerized tomography angiography is useful for follow up of patients with aneurysms because it allows the detection of even subtle morphological changes.

Adult↗
PubMed2003

Central nervous system lesions associated with hereditary hemorrhagic telangiectasia--three case reports.

Hereditary hemorrhagic telangiectasia (HHT) is easily overlooked in patients with central nervous system (CNS) lesions. Our clinical experience of three patients with CNS lesions associated with HHT stresses the importance of considering HHT. A 23-year-old male presented with consciousness disturbance and right hemiparesis. Emergency cerebral digital subtraction angiography revealed occlusion of the left middle cerebral artery and the left anterior cerebral artery. Pulmonary arteriography showed three pulmonary arteriovenous malformations (AVMs). A 62-year-old male presented with consciousness disturbance and sensory aphasia. Magnetic resonance imaging revealed a ring-enhanced lesion in the left temporal lobe which was removed by left frontotemporal craniotomy. The diagnosis was brain abscess. Chest computed tomography (CT) revealed two pulmonary AVMs. A 32-year-old female presented with progressive mild weakness in her left hand. Initial CT showed subcortical hemorrhage in the right frontal lobe. Cerebral angiography revealed no vascular malformations, but chest CT disclosed five pulmonary AVMs. All three patients had a family history of HHT. The possibility of HHT is important to consider in patients with cerebrovascular disease (CVD) or brain abscess to prevent complications, not only in the patients but also their blood relatives. Therefore, the medical and family history of patients with CVD or brain abscess should be investigated and HHT should be considered during the physical examination.

Adult↗
PubMed2002

Can diffusion- and perfusion-weighted magnetic resonance imaging evaluate the efficacy of acute thrombolysis in patients with internal carotid artery or middle cerebral artery occlusion?

OBJECTIVE: The value of combined diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) for detecting ischemic lesions of patients with acute ischemic injury was analyzed. Combined pre- and posttreatment DWI and PWI studies were used to assess the efficacy of intra-arterial thrombolysis. METHODS: Intra-arterial thrombolysis was performed within 6 hours of onset in 10 patients who presented with acute middle cerebral artery or internal carotid artery occlusion. DWI and PWI obtained before and after treatment were studied. The final T2-weighted magnetic resonance scans were obtained 1 month after onset. Thrombolysis resulted in recanalization in seven patients. The mismatch ratio percentage ([initial PWI-initial DWI/initial PWI] x 100) and the rescued ratio percentage ([initial PWI-final T2/initial PWI] x 100) were calculated. The National Institutes of Health Stroke Scale (NIHSS) was used for neurological assessment of stroke severity at admission and at 1 month after onset. RESULTS: In all patients, the mismatch ratio was greater than 60% (mean +/- standard deviation, 81.7 +/- 16.7%) and was significantly correlated with initial NIHSS score (-0.74; P = 0.03), and the rescued ratio was significantly correlated with the NIHSS score 1 month after the insult (r = -0.83; P = 0.01). In patients who exhibited recanalization of the occluded artery (n = 7), the mean rescued ratio was 89.6 +/- 12.8% (range, 63-100%). In addition, the lesion volume on posttreatment DWI scans and final T2-weighted magnetic resonance images was not enlarged; on posttreatment PWI scans, it was significantly decreased. The NHISS score at 1 month after the insult (2.3 +/- 2.1) was markedly improved as compared with the initial NHISS score (10.7 +/- 3.9). CONCLUSION: In a small number of patients who presented with internal carotid artery or middle cerebral artery occlusion, the DWI/PWI mismatch ratio correlated with the initial neurological severity. The rescued ratio may be an objective indicator of the efficacy of treatment.

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