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ABSTRACT: BACKGROUND: We aimed to evaluate the validity of duplex ultrasonography (DUS) using a microconvex array transducer (MAT) with enhanced flow imaging (EFI) for visualization of the distal, internal carotid artery (ICA) and the accurate assessment of ICA stenosis. METHODS: Patients who underwent both DUS and digital subtraction angiography (DSA) were registered for this study. DUS was performed by using a linear array transducer (LAT) and an MAT with EFI. The visibility of the ICA was compared between the 2 transducers. ICA stenosis was evaluated by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method on DUS, and the peak systolic flow velocity (PSV) was evaluated by using an MAT. These results were compared with DSA. RESULTS: In 238 internal carotid arteries, the average length of visualized ICA was longer for DUS using an MAT than an LAT (38.7 ± 11.7 mm versus 25.8 ± 9.8 mm, P < .0001). In 68 stenotic, internal carotid arteries, the degree of ICA stenosis detected by the NASCET method on DUS was correlated to that on DSA (P < .0001, r = .969, and adjusted r(2) = .938). PSV also correlated to NASCET method on DSA (P < .0001, r = .804, and adjusted r(2) = .640). CONCLUSIONS: DUS using an MAT with EFI technology could reveal more extended distal views of the ICA and was strongly correlated with NASCET method on DSA.
Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 04/2013;
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ABSTRACT: BACKGROUND AND PURPOSE: Artery-to-artery embolism generally occurs in patients with not only moderate to severe arterial stenosis but also plaque vulnerability. Two unique cases with free-floating thrombi at the distal side of the small plaque in the internal carotid artery without stenosis are presented and its clinical implications are discussed. RESULTS: Two middle-aged men suffered embolic stroke. Initial duplex ultrasonography revealed small plaques and vortex flow without significant stenosis or plaque vulnerability in their internal carotid arteries. Continuous examination by duplex ultrasonography showed that free-floating thrombi developed and regressed at the distal side of the small plaques. Histological examination disclosed plaque erosion at the distal side of the plaques without lipid core rupture. CONCLUSIONS: In these two cases, duplex ultrasonography revealed free-floating thrombi developed at the distal region of small plaques. Aggressive treatment should be considered in a patient with thromboembolic stroke who has the small plaque presenting "snake fang" sign even if there is no stenosis or plaque vulnerability.
Journal of neuroimaging: official journal of the American Society of Neuroimaging 12/2012; · 1.72 Impact Factor
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ABSTRACT: The authors present the case of a 78-year-old man who presented with a subarachnoid hemorrhage due to rupture of an aneurysm at the origin of the persistent primitive olfactory artery (PPOA). Interestingly, the PPOA was originating from the A1 segment of the anterior cerebral artery and coursed anteromedially along the olfactory tract. Moreover, the PPOA in this case had 2 branches: the branch making a hairpin turn and supplying the distal part of the anterior cerebral artery territory (Type 1), and the branch extending to the cribriform plate to supply the nasal cavity (Type 2). To the best of the authors' knowledge, this is a new variant (Type 3) of PPOA associated with a ruptured aneurysm. The clinical implications of this case are discussed in terms of the embryological aspects.
Journal of Neurosurgery 04/2012; 117(1):26-8. · 2.96 Impact Factor
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ABSTRACT: Coil migration during cerebral aneurysm embolization is rare, but one of the most troublesome events. A 65-year-old woman was referred to our hospital for the treatment of a cerebral aneurysm. Angiography showed the aneurysm at the C3 portion of the right internal carotid artery. The neck of the aneurysm was wide. A detachable coil was placed into the aneurysm using the balloon neck plasty technique and was detached after confirmation of its stability. However, after detachment, the coil started to migrate. The balloon was inflated to prevent coil migration and another coil was inserted into the aneurysm to stabilize the migrated coil. Finally, the aneurysm was subtotally embolized with 9 coils. The postoperative course was uneventful. Coil migration may occur especially in a wide-neck aneurysm. Appropriate coil selection is important to prevent such migration. Subsequent coil insertion, retrieval of the migrated coil, and stent placement are the treatment options for coil migration.
No shinkei geka. Neurological surgery 03/2012; 40(3):271-6. · 0.13 Impact Factor
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Acta Neurochirurgica 02/2012; 154(6):989-91. · 1.52 Impact Factor
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Kenta Ujifuku,
Takayuki Matsuo,
Keisuke Toyoda,
Shiro Baba,
Tomohiro Okunaga,
Yukishige Hayashi,
Kensaku Kamada, Minoru Morikawa,
Kazuhiko Suyama,
Izumi Nagata,
Nobuyuki Hayashi
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ABSTRACT: A 63-year-old woman presented with right hearing disturbance and vertigo. Magnetic resonance (MR) imaging revealed the presence of right vestibular schwannoma (VS). Stereotactic radiosurgery (SRS) was performed with a tumor marginal dose of 14 Gy using two isocenters. She was followed up clinically and neuroradiologically using three-dimensional spoiled gradient-echo MR imaging. She experienced temporal neurological deterioration due to peritumoral edema in her right cerebellar peduncle and pons for a few months beginning 1.5 years after SRS, when she experienced transient right facial dysesthesia and hearing deterioration. Ten years after SRS, the patient presented with sudden onset of vertigo, gait disturbance, diplopia, dysarthria, and nausea. MR imaging demonstrated a new lesion in the right cerebellar peduncle, which was diagnosed as radiation-induced stroke. The patient was followed up conservatively and her symptoms disappeared within a few months. Multiple delayed onset radiation injuries are possible sequelae of SRS for VS.
Neurologia medico-chirurgica 01/2012; 52(12):933-6. · 0.61 Impact Factor
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ABSTRACT: The authors report a case of ruptured giant thrombosed aneurysm successfully treated with endovascular internal trapping following emergent balloon occlusion test (BOT), and discuss its clinical implications regarding emergent BOT. A 41-year-old female showing massive epistaxis was referred to our institute for the treatment of a giant aneurysm. Computed tomography and digital subtraction angiography revealed a giant thrombosed aneurysm located at the petrous portion of the right internal carotid artery with an erosion of the petrous bone. Emergent BOT was performed under the monitoring of regional oxygen saturation of the brain (rSO₂) and stump pressure as well as neurological changes and confirmed tolerance for permanent internal artery occlusion with a little change of rSO₂ and stump pressure. Endovascular internal trapping was performed with detachable coils and the postoperative course was uneventful. Magnetic resonance imaging showed a decrease in the size of the aneurysm three month after the treatment, and the aneurysm got organized four years later. For ruptured aneurysms, emergent BOT is sometimes difficult to perform due the neurological deterioration or inability to prepare radioisotope for single photon computed tomography. Nevertheless, monitoring of rSO₂ and stump pressure as well as neurological changes can be of help for decision making concerning the treatment strategy. Endovascular treatment following BOT is a feasible and life-saving approach for emergent management of ruptured internal carotid artery aneurysms presented with massive epistaxis.
No shinkei geka. Neurological surgery 01/2012; 40(1):61-6. · 0.13 Impact Factor
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ABSTRACT: The authors present the case of a 66-year-old female who developed progressive pulsating exophthalmos, a bruit, and conjunctival chemosis 7 months after a head injury. These symptoms, though highly suspicious of carotid cavernous fistula, were caused by an arteriovenous fistula (AVF) between the inferolateral trunk (ILT) and the ophthalmic veins. A direct AVF at the branch of the ILT without involvement of the cavernous sinus is extremely rare, but could occur in the case of acquired AVF since the ILT has some branches around venous structures outside the cavernous sinus. The clinical implications of this case are discussed in terms of the anatomical aspects.
Acta Neurochirurgica 11/2011; 154(3):465-9. · 1.52 Impact Factor
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ABSTRACT: Recent studies have investigated plaque morphology to determine patients who are at high risk of carotid atherosclerosis. In this study, we investigated whether a difference in dynamic enhancement pattern in plaque components could be useful to assess plaque stability with multidetector CT angiography.
Fifty-nine lesions with moderate to severe carotid atherosclerosis in 51 patients (33 symptomatic, 18 asymptomatic) were consecutively included. Early- and delayed-phase images were obtained in 3 equivalent axial slices with multidetector CT angiography. Hounsfield units (HU) in the early phase were subtracted from those in the delayed phase in plaques (ΔHU) and compared with clinical features, MRI-based plaque characteristics, and histological findings with 20 surgical specimens acquired from carotid endarterectomy.
The ΔHU was significantly higher in asymptomatic than that in symptomatic presentation (P=0.02). With MRI, a higher ΔHU was negatively correlated with signal intensity on T1-weighted imaging (r=-0.56, P<0.0001). Histology confirmed that ΔHU was positively correlated with fibrous tissue (r=0.67, P=0.001) and negatively correlated with a lipid-rich necrotic core with hemorrhage (r=-0.70, P<0.001). Moreover, less neovascularization and inflammation was found in plaques with a higher ΔHU.
Delayed-phase images provide information regarding the dynamic change in contrast media from the early arterial phase. An increase in HU from the early phase on multidetector CT angiography indicates plaque stability with more fibrous tissue and a less lipid-rich necrotic core, intraplaque hemorrhage, and neovascularization.
Stroke 11/2011; 43(2):393-8. · 5.73 Impact Factor
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ABSTRACT: Blood blister-like aneurysms (BBAs) tend to have a more precipitous clinical course, enlarging rapidly and rebleeding frequently. Nevertheless, they often present a diagnostic challenge because of the characteristic morphological features of a wide neck and shallow outpouching of the medial wall. The authors present the case of a 34-year-old woman who suffered a subarachnoid hemorrhage whose cause could not be determined on the initial imaging with digital subtraction (DS) angiography and CT angiography. Interestingly, MR imaging studies obtained on the 7th day revealed an intramural hematoma on the dorsal wall of the left internal carotid artery, which helped in the diagnosis of BBA on the third DS angiography study obtained on the 8th day, and in the surgical intervention on the 10th day. This case supports the hypothesis that focal dissection contributes to the formation of BBAs. Use of MR imaging in the subacute stage, in addition to DS and CT angiography, might be helpful in the diagnosis of BBAs.
Journal of Neurosurgery 09/2011; 115(6):1206-9. · 2.96 Impact Factor
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ABSTRACT: We first present 2 cases of spinal arteriovenous fistulae (AVFs) successfully treated with the help of intra-arterial indocyanine green (ICG) angiography.
To demonstrate the efficacy of intra-arterial ICG angiography in spinal AVFs compared with the role of intravenous ICG injection and intraoperative digital subtraction angiography (DSA).
Intravenous ICG fluorescent angiography is an emerging intraoperative tool to recognize vascular anatomy. The technique is quite simple and provides real-time vascular hemodynamics in the operative field. However, it takes time for the ICG to be washed out; therefore, repeat studies are somewhat tedious and time consuming, especially in spinal AVFs with multiple shunts/drainer. In this setting, intraoperative DSA has still been the standard to confirm the complete obliteration, although this has a risk of radiation exposure and renal failure.
Two patients, a 46-year-old man with spinal dural AVF at the cervicomedullary junction and a 68-year-old woman with spinal perimedullary AVF at the conus medullaris, were surgically treated with the help of intra-arterial ICG angiography.
We introduced a catheter into the target artery and injected 0.05 mg ICG in 2 mL of normal saline in multiple, short intervals. This approach enabled us to detect the residual shunt/drainer and confirm complete obliteration. With this technique, a tiny amount of ICG was used in the operative field to clearly label only the affected vessels. Intraoperative DSA was not performed in these cases.
These cases demonstrate that intra-arterial ICG angiography is a powerful tool for visualizing spinal AVFs in terms of addressing the disadvantages of intravenous ICG injection and intraoperative DSA.
Spine 07/2011; 37(4):E264-7. · 2.08 Impact Factor
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ABSTRACT: To evaluate the relationship between preoperative analysis of platelet aggregability and perioperative complications, we analyzed 42 patients who underwent carotid endarterectomy or carotid artery stenting. The effect of antiplatelet drugs was tested by whole blood aggregometry. ADP (adenosine-diphosphoric acid) and collagen were used as agonists. According to platelet aggregability, patients were classified into 4 groups (class A: highly inhibited, class B: moderately inhibited, class C: normally inhibited, class D: non-inhibited). Seven (32%) of 22 patients were stratified as clopidogrel nonresponders, whereas four (10%) of 40 patients were aspirin nonresponders. Hemorrhagic complications were registered in four patients. All of them were classified as class A. Ischemic complications occurred in two patients, one was classified as class C, the other was class D. Preoperative analysis of platelet aggregability could be useful to reduce the risk of perioperative complications after carotid surgery.
No shinkei geka. Neurological surgery 05/2011; 39(5):459-63. · 0.13 Impact Factor
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ABSTRACT: Leptomeningeal high signal intensity (ivy sign) on fluid-attenuated inversion-recovery (FLAIR) MR imaging is one of the features of Moyamoya disease. However, the correlation between ivy sign and cerebral perfusion status has not been fully evaluated.
To characterize ivy sign on FLAIR images in Moyamoya disease and compare this finding with hemodynamic alterations on perfusion single-photon emission CT (SPECT) obtained before and after bypass surgery.
Sixteen patients with angiographically confirmed Moyamoya disease who underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis were included in the study. The presence of ivy sign on FLAIR images was classified as 'negative', 'minimal' and 'positive'. We evaluated the relationship between ivy sign and findings of SPECT, including cerebral vascular reserve (CVR) before and after surgery.
Minimal or positive ivy sign was seen in 13 (81%) of 16 patients, and 21 (66%) of 32 hemispheres. CVR in the areas with positive or minimal ivy sign was lower than that in the areas with negative ivy sign. After STA-MCA anastomosis, ivy sign disappeared or decreased in all 21 hemispheres demonstrating ivy sign. SPECT demonstrated apparent hemodynamic improvement in areas demonstrating disappearance or decrease of ivy sign.
Ivy sign on FLAIR image is seen in areas with decreased cerebral perfusion. The sign is useful for non-invasive assessment of cerebral hemodynamic status before and after surgery.
Acta Radiologica 04/2011; 52(3):291-6. · 1.37 Impact Factor
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ABSTRACT: Recently, endovascular management has been reported as a feasible option for Takayasu aortitis. However, few papers have focused on restenosis in the follow-up, and therefore, it is important to predict high-risk cases for restenosis after endovascular treatment. We herein report three cases with Takayasu aortitis showing repeated restenosis after endovascular percutaneous transluminal angioplasty (PTA)/stenting and discuss its clinical implications with a review of the literature. We should keep in mind that endovascular PTA/stenting for Takayasu aortitis does not always keep the patency of the affected vessels, and severity of the stenosis and/or uncontrollable systemic inflammation could be a risk factor for restenosis. Therefore, careful follow-up under strict control of inflammation is mandatory. Overall, this method is effective as an initial treatment since repeated PTA is available until collateral supply develops.
Acta Neurochirurgica 02/2011; 153(5):1135-9; discussion 1139. · 1.52 Impact Factor
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Acta Neurochirurgica 12/2010; 153(5):1143-4. · 1.52 Impact Factor
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ABSTRACT: The Rubinstein-Taybi syndrome (RTS) is defined congenital anomalies and is characterized by postnatal growth deficiency, microcephaly, specific facial characteristics, broad thumbs and big toes, and mental retardation. RTS displays an autosomal dominant inheritance pattern and is typically caused by cAMP response element-binding (CREB)-binding protein deficiency. Various complications such as eye anomalies and a variety of congenital heart defects are reported in such cases. We treated an RTS patient who had a dissecting aneurysm of the anterior cerebral artery. The patient was a 44-year-old man who was brought to our hospital because of sudden left hemiplegia. Magnetic resonance images showed a cerebral infarction caused by anterior cerebral artery dissection. Coil embolization was performed on enlargement of the dissecting aneurysm, and the procedure was successful. Conclusion: RTS may be accompanied by cerebrovascular disease.
Brain and nerve = Shinkei kenkyū no shinpo 10/2010; 62(10):1083-8.
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ABSTRACT: Although aneurysm formation accompanying parenchymal hemorrhage is one of devastating complications in the central nerves system (CNS), imaging studies of the brain are not routinely warranted in patients with infective endocarditis (IE). To assess the clinical importance for detecting silent lesions in the central nervous system, we investigated hypointense signal spots detected on the brain T2*-weighted MR imaging in patients with IE.
Eleven patients with IE were retrospectively reviewed. Seven patients (63.6%) showed hypointense signal spots on T2*-weighted MR images. The number of hypointense signal spots increased within only a few weeks in five patients.
The brain T2*-weighted MR imaging in patients with IE may have a potential role to detect CNS lesions with clinical significance of potentially high risk of intracranial hemorrhage. T2*-weighted hypointense signal spots may be specific to brain involvement, and be quite useful in monitoring CNS lesions associated with IE, even if they are asymptomatic.
Clinical neurology and neurosurgery 04/2010; 112(5):436-40. · 1.30 Impact Factor
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ABSTRACT: The hemostatic puncture closure device Angio-Seal is a quick and easy-to-use system, allowing rapid sealing of the vascular access site after interventional procedure. The rate of complications associated with the use of this device has been reported to be low; nonetheless, certain specific complications may arise. In the present study, we describe a case of vascular occlusion that occurred because of the use of the Angio-Seal device. A 59-year-old man with no sign of peripheral arterial occlusive disease underwent carotid artery stenting. The left common femoral artery was closed with the Angio-Seal device. After 7 days, the patient complained of intermittent claudication, especially while climbing up the stairs. Angiography of the left iliac artery at 2 months after carotid artery stenting revealed occlusion of the left common femoral artery. Deep and superficial femoral arteries were fed by the collateral flow from the muscle branch. Because the patient's symptom was mild and his daily life was not affected, he was treated conservatively. In conclusion, arterial closure performed using a hemostatic device is associated with a risk of vascular occlusion.
Brain and nerve = Shinkei kenkyū no shinpo 02/2010; 62(2):173-6.
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ABSTRACT: Granulocytic sarcoma consists of neoplastic granulocytic precursors and myeloblasts. It is a focal lesion seen in 2-10.9% of acute myelogenous leukaemia (AML) patients. It usually develops either concurrently with the AML or after a remission. On rare occasions, it may be an initial manifestation of AML. Most common involvement sites are bone, periostium, soft tissue, lymph nodes and skin. Intracranial granulocytic sarcoma rarely occurs in meningeal or parenchymal form. We present an extremely rare case of intracranial granulocytic sarcoma extending from the posterior fossa to the carotid space via the jugular foramen in a 69 year old female. This form of involvement has not been previously reported. On MRI, the lesion appears isointense compared with normal grey matter in T1 and T2 weighted images and shows homogeneous contrast enhancement. With these findings, it is difficult to differentiate the lesion from other extraaxial tumours such as meningioma, paraganglioma, schwannoma, carcinoma, metastatic tumor, malignant lymphoma. However, granulocytic sarcoma, densely increased tumour cells restrict diffusion and reduce the extracellular volume fraction, tends to be markedly hyperintense on diffusion-weighted MR images and exhibits a marked decrease in ADC values. Therefore, DWI may be helpful in differentiating granulocytic sarcoma from other intracranial lesions.
No shinkei geka. Neurological surgery 01/2010; 38(1):53-9. · 0.13 Impact Factor
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ABSTRACT: Preoperative embolization of cranio-cervical tumors is commonly used to reduce intraoperative blood loss. Gelpart is a new collagen embolic agent. Because of its porous structure, it is deformable and tends not to aggregate. The purpose of this study is to evaluate the efficacy of the Gelpart embolization for cranio-cervical tumors.
The shape and size of Gelpart was observed under high-resolution microscope. Eight cases of cranio-cervical tumors were treated with Gelpart embolization. A microcatheter was introduced to the feeding artery and Gelpart, mixed with contrast medium, was injected manually. The effect of the Gelpart embolization was evaluated with MRI and operative specimen.
The shape of Gelpart was not spherical, but the surface became smooth after mixture with contrast medium. Gelpart injection proceeded smoothly and it resulted in excellent angiographical devascularization. No complications occurred related to the Gelpart embolization. At surgery, the tumor was soft and was removed easily. Intraoperative blood loss was relatively less than that using often method. Gelpart embolized peritumoral small arteries and induced tumor necrosis.
We reported our preliminary experience of Gelpart for preoperative embolization of cranio-cervical tumors. Gelpart was effective for tumor embolization.
No shinkei geka. Neurological surgery 08/2009; 37(7):651-6. · 0.13 Impact Factor
