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ABSTRACT: A 68-year-old man presented with right cervical carotid artery stenosis manifesting as ipsilateral amaurosis fugax. Angiography showed non-bifurcating cervical carotid artery with atherosclerotic stenosis near the branching of the superior thyroid artery. Carotid artery stenting (CAS) was carried out using two balloons for embolic protection of the internal carotid artery and middle meningeal artery because the ophthalmic artery was supplied by the middle meningeal artery. No procedure-related complications or restenosis occurred after stenting. Non-bifurcating cervical carotid artery is a very rare anomaly, in which the branches of the external carotid artery directly arise from the common trunk of the carotid artery without forming a bifurcation. The present patient was successfully treated with CAS for atherosclerotic stenosis associated with non-bifurcating cervical carotid artery.
Neurologia medico-chirurgica 01/2013; 53(4):228-32. · 0.61 Impact Factor
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ABSTRACT: Although large and giant aneurysms can induce visual disturbance by compression of the anterior visual pathway, splitting and penetration of the optic apparatus are extremely rare. The authors describe three patients who underwent clipping surgery for anterior communicating artery aneurysm infiltrating into the optic nerve or chiasm. These findings were suspected on preoperative magnetic resonance imaging and confirmed at surgery. Two aneurysms were ruptured and one unruptured. The authors review the literature and discuss the mechanism of cranial nerve penetration by an aneurysm.
06/2011; 35(3):128-132.
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ABSTRACT: Intracranial arterial dissections of the vertebrobasilar system are recognized as a cause of stroke. Although the pathogenic mechanism underlying this phenomenon is unknown, in some cases the stroke originates from subarachnoid hemorrhage, while in others ischemia is the cause. In cases where hemorrhage occurs, occlusion of the lesion is effective in reducing the risk of re-bleeding. However, deciding on treatment is difficult in uncommon cases in which occlusion occurs immediately after hemorrhage. Intracranial arterial dissections of the vertebrobasilar system often present as subarachnoid hemorrhage, and the most appropriate surgical treatment remains controversial. In this report, we describe a rare case of vertebral artery dissection in which occlusion occurred immediately after subarachnoid hemorrhage. Serial angiography revealed spontaneous recanalization of the right vertebral artery dissection, as well as enlargement. The progressive angiographic changes of the ruptured vertebral artery dissection and the endovascular treatment of such arterial dissections are discussed.
Journal of Clinical Neuroscience 07/2008; 15(6):700-3. · 1.25 Impact Factor
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Yuichiro Tanaka,
Toshiki Takemae, Shigeaki Kobayashi,
Keiichi Sakai,
Takahiro Miyahara,
Shigetoshi Ishizaka,
Kunihiko Kodama,
Tatsuya Kobayashi,
Yozo Ichikawa,
Keiji Tsutsumi,
Kazuhiro Hongo
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ABSTRACT: In order to improve QOL in patients with craniopharyngioma, retrospective analysis was performed to discover factors for influencing functional outcome and the best treatment strategy. 56 patients were treated between 1978 and 2005. They were initially treated with surgery and surgical cure was obtained in 29 patients (Group A). Subtotal tumor resection with prophylactic radiation was performed in 8 patients (Group D). Tumor recurrence was noted in 19 patients and stereotactic radiation or 2nd operation was performed in 11 patients (Group B). 2nd operation and fractionated radiation were undertaken in 8 patients (Group C). Endocrine, vision and recognition were scored from 2 to 0, respectively; 2 indicates normal, 1 partially disturbed, 0 fully disturbed. The mean score before treatment was 4.7 and the final score was 3.9. Factors leading to poor outcome included extrasellar origin, solid tumor, bad score before treatment, 2nd surgery for recurrence. The change of scores after the treatment was -0.1 in group A, -0.7 in Group B, -0.9 in Group C and 0.3 in Group D. Maximum tumor removal should be attempted with functional preservation. Subtotal removal with prophylactic radiation is recommended if the patient has normal hypothalamic function.
No shinkei geka. Neurological surgery 10/2007; 35(9):887-93. · 0.13 Impact Factor
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ABSTRACT: We report a patient in whom placement of a ventriculoperitoneal shunt for obstructive hydrocephalus secondary to non-neoplastic aqueductal stenosis was complicated by progressive parkinsonism and midbrain dysfunction. These sequelae were refractory to treatment, including shunt revision and levodopa therapy. These findings contradict the opinion from the literature that this type of parkinsonism is a reversible condition and levodopa therapy is effective for managing the symptoms. We discuss the pathophysiological mechanism of this complication.
Journal of Clinical Neuroscience 05/2006; 13(3):373-8. · 1.25 Impact Factor
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ABSTRACT: This study was conducted to determine the incidence, severity, and causes of delayed vasospasm after clipping of unruptured paraclinoid aneurysms of the internal carotid artery (ICA). A retrospective analysis was made of 30 patients, who underwent clipping of unruptured paraclinoid aneurysms in our institution between 1991 and 1998. We compared angiograms before and after operation and classified them into two groups: vasospasm group and non-vasospasm group. Eleven variables were assessed as to their relationship to delayed vasospasm. There were 9 patients (30%) in the vasospasm group, of which 3 patients (10%) were clinically symptomatic. For all symptomatic patients, aggressive treatment, including triple-H therapy, was conducted with good outcome. The number of clips used (p<0.04) and temporary occlusion of the ICA (p<0.005) were statistically significant factors associated with the incidence of vasospasm. It is suggested that mechanical stimulation to the vascular wall of the ICA is responsible for causing spasm in addition to intraoperative bleeding around the dural ring.
Journal of Clinical Neuroscience 03/2005; 12(2):150-5. · 1.25 Impact Factor
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ABSTRACT: A case of a histologically unclassified brain tumor in a 32-month-old boy is reported. He presented with vomiting, appetite loss, and right motor weakness. MR images revealed a huge mass in the left frontoparietal region that was enhanced after the administration of Gd-DTPA. The mass was removed three times because of its recurrence.
Histologically, the tumor was composed largely of small-undifferentiated round cells without any patterns of differentiation. Immunohistochemically, the tumor cells were positive for cytokeratin and focally for epithelial membrane antigen (EMA). Glial fibrillary acidic protein (GFAP), S-100 protein and neuronal markers were negative. Electron microscopic investigations demonstrated no evidence of specific differentiation. MIB-1 staining index was 10-40%. The origin of the tumor was not detected. Expression of the hSNF5/INI1 of this tumor was not detected by reverse transcription-polymerase chain reaction (RT-PCR). The patient has been in a good condition for 7 years after the first operation.
Based on the immunohistochemical findings, the tumor was descriptively diagnosed as an embryonal tumor with an epithelial immunophenotype. The hSNF5/INI1 gene has recently been reported to act as a tumor suppressor in atypical teratoid/rhabdoid tumors. The hSNF5/INI1 gene may lead to tumorigenesis in this case.
Child s Nervous System 03/2005; 21(2):150-5. · 1.54 Impact Factor
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ABSTRACT: The purpose of this study was to retrospectively evaluate and compare the feasibility, indication and limitations of two treatment options, clipping and coil embolization, for basilar artery (BA) bifurcation aneurysms.
During the last 13 years, 117 patients with 117 BA bifurcation aneurysms were treated exclusively with direct surgery until February 1997, and with either direct surgery or coil embolization therapy since March 1997. Of them, 76 (65%) aneurysms were treated with direct clipping and 41 (35%) were treated with Guglielmi detachable coils (GDCs) embolization. The 76 surgically clipped aneurysms were analyzed on the basis of the pre-operative angiograms as to whether coil embolization would be feasible or not if each case had been attempted. The 41 embolized aneurysms, on the other hand, were analyzed as to whether clipping surgery would be feasible or not if it had been attempted.
In the total 117 aneurysms, complete coil obliteration was judged to be possible and simple in 61 (52%) aneurysms, possible with complex techniques (difficult) in 29 (25%) and impossible in 27 (23%). Whereas, complete obliteration with direct clipping was judged to be simple in 66 (57%) aneurysms, difficult in 38 (32%) and impossible in the remaining 13 (11%). Linear correlation as to the technical difficulty was found in 61 (52%) aneurysms, but 14 (12%) had marked discrepancy between the two methods. Of the 76 patients treated with clipping surgery, 17 (22%) were left with some post-operative neurological deficits, and in six out of the 17 aneurysms, embolization might have been simple. There were complications in two patients; one procedure-related and the other with late re-bleeding due to aneurysmal re-growth, in the embolization, group.
Endovascular therapy is an effective alternative for treating BA bifurcation aneurysms, although a quarter of the cases cannot be obliterated completely. It is important to select a suitable treatment option in each case depending on the patient's condition and the angiographical features of each aneurysm as well as the characteristics of the two methods.
Journal of Clinical Neuroscience 07/2004; 11(5):475-9. · 1.25 Impact Factor
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ABSTRACT: The purpose of this article is to assess, in a 25-year retrospective study, the clinical outcome in children with craniopharyngioma.
From 1978 to 2002, 12 children younger than 15-year-old underwent treatment with surgery and/or radiotherapy for craniopharyngioma. The clinical course and outcome were reviewed.
The median age was 7.3 years (range, 3 to 12 years) at the time of initial surgical resection. With a mean follow-up period of 132 months (range, 29 to 255 months), 1 patient died of tumor progression due to malignant transformation at 205 months after the initial surgery and the overall outcome was good in 11 patients. Out of 12 patients 4 presented a recurrence of their tumor, 2 after an apparently gross total removal. Because of tumor recurrence, 2 received conventional radiation therapy and 3 received gamma knife radiosurgery. There was neither operative mortality nor major complication. All patients required hormonal replacement postoperatively.
The goal in the treatment of craniopharyngiomas is to achieve total removal without morbidity. Our results compared favorably with the previous reports in the literature. MRI follow-up should be performed even in patients whose primary tumor is resected "completely". Suitable combination of open surgery, conventional radiotherapy and gamma knife radiosurgery may result in optimal functional outcome. Recovery from postoperative pituitary dysfunction can be occasionally expected.
No shinkei geka. Neurological surgery 05/2004; 32(4):345-53. · 0.13 Impact Factor
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ABSTRACT: A 24-year-old woman was struck on the head by a hammer. Because of early signs and symptoms of intercranial hypertension, she underwent surgery for elevation of the depressed fragments which was compressing the superior sagittal sinus (SSS). After operation, the intracranial pressure (ICP) once decreased, but it gradually increased again. After hypothermia and barbiturate therapy, she recovered fully except for partial visual field defect due to brain contusion. A carotid angiogram 28 days after injury revealed complete occlusion of the whole SSS with good collateral circulation. After brain edema had subsided, a follow-up angiogram revealed normal blood flow through the SSS. Elevation of depressed bony fragments is required for a case presenting with early signs and symptoms of intracranial hypertension due to sinus compression. In a case with severe destruction of the SSS, one needs to know that re-occlusion of the dural sinus may occur after surgical recanalisation.
Journal of Clinical Neuroscience 05/2004; 11(3):322-4. · 1.25 Impact Factor
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ABSTRACT: The NeuRobot is a telecontrolled microscopic micromanipulator system designed for neurosurgical procedures. The unit houses a three-dimensional endoscope and three robot arms that the surgeon operates without direct contact with the patient. The authors have successfully performed robotics-assisted neurosurgical procedures by using the NeuRobot in a 54-year-old man who had a recurrent atypical meningioma. Following the usual preparation of craniotomy and opening of the dura mater, a portion of the tumor was removed using the NeuRobot with the aid of microscopic observation. No complication related to the use of the NeuRobot was encountered and the patient's postoperative course was uneventful. Although various kinds of robots have been developed for use in neurosurgery in recent years, a robotic telemanipulation system capable of performing several surgical tasks has not previously been introduced to clinical neurosurgery. This is the first case report in which neurosurgical manipulation by a robotics system is described.
Journal of Neurosurgery 01/2004; 99(6):1082-4. · 2.96 Impact Factor
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ABSTRACT: As far as we know, 6 cases of extracranial (including craniocervical junction) intradural aneurysms of the posterior inferior cerebellar artery have been previously reported. However, preoperative detailed evaluation of the origin site and a course of the posterior inferior cerebellar artery by means of angiography were not reported in previous papers.
We report a rare case of aneurysm of the posterior inferior cerebellar artery, which originated extradurally from the right vertebral artery. A 69-year-old woman experienced a sudden headache 16 years ago and a computed tomography scan showed a subarachnoid hemorrhage around the midbrain. Four-vessel cerebral angiography, however, failed to disclose a source of the hemorrhage. Magnetic resonance angiography incidentally revealed an aneurysm at the craniocervical junction 16 years after the subarachnoid hemorrhage. The aneurysm was exposed and clipped via a suboccipital route. At surgery, it was of no use to apply a temporary clip on the intradural segment of the vertebral artery, because the posterior inferior cerebellar artery was found to enter the intradural space separately from the vertebral artery. The blood flow to such an aneurysm cannot be stopped with this procedure.
Careful neuroimaging study is essential for the accurate diagnosis and successful treatment of such a rare aneurysm.
Surgical Neurology 11/2003; 60(4):329-33; discussion 333. · 1.67 Impact Factor
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ABSTRACT: Distal posteroinferior cerebellar artery (PICA) aneurysms are rare and have not been well investigated previously. We report our series of 24 patients with 27 distal PICA aneurysms.
All patients with distal PICA aneurysms that were surgically treated at Shinshu University Hospital and its affiliated hospitals between 1983 and 2001 were reviewed retrospectively. Data relating to clinical, radiological, and intraoperative findings were analyzed.
In our series, distal PICA aneurysms reached an incidence of 0.28 and 0.38% of all intracranial aneurysms and ruptured aneurysms, respectively. There were 23 ruptured and 4 unruptured distal PICA aneurysms. Of these, 74.1% were saccular, 7.4% fusiform, and 18.5% dissecting aneurysms. Primarily the telovelotonsillar segment of the PICA was affected. Usually, the surgical outcome was favorable and was influenced by the obstructive hydrocephalus and the preoperative grade. It was sometimes difficult to detect the ruptured distal PICA aneurysm on the initial angiogram, and an extracranial origin of the PICA was sometimes observed.
This review summarizes the presentation and outcome of a large series of 24 patients with 27 distal PICA aneurysms, and we conclude that distal PICA aneurysms are benign entities compared with vertebral artery-PICA aneurysms. Characteristics that should be considered in the treatment of distal PICA aneurysms are discussed.
Neurosurgery 10/2003; 53(3):589-95; discussion 595-6. · 2.79 Impact Factor
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ABSTRACT: Various methods have been used to report the tumor diameter of vestibular schwannomas. To clarify the most appropriate method to represent the tumor volume, tumor diameters according to various measuring methods were statistically compared with the actual tumor volume.
Tumor volume was measured by three-dimensional constructive interference in steady state images in 52 unselected vestibular schwannomas. Pearson's correlation coefficient was obtained between the tumor volume and various tumor diameters, such as diameter parallel to the petrous edge (a); a pons-to-petrous diameter (b); ab, a maximum diameter of the portion in the cerebellopontine angle cistern (max CPA); a maximum diameter of the whole tumor (Max); and a diameter through an axis of the internal auditory canal (Axis). The tumors were divided into three groups on the basis of tumor volume, as follows: Group I (small, <0.5 cm(3)), Group II (medium, 0.5-2 cm(3)), and Group III (large, >2 cm(3)).
Max and Axis correlated best with the tumor volume in Group I and correlated least with the tumor volume in Group II. Any of these measurements was acceptable in Group III tumors. The max CPA consistently revealed good correlation with the tumor volume in all three tumor groups.
The max CPA measurement is the simplest and most appropriate way to represent the tumor volume in unselected tumors. Max or Axis is better only when small tumors (<0.5 cm(3) in volume) are being assessed-that is, those with a max CPA of less than 1 cm.
Neurosurgery 09/2003; 53(3):634-7; discussion 637-8. · 2.79 Impact Factor
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ABSTRACT: A new method was developed to avoid the risk of injury to the cranial nerves and vessels during intradural bone resection at the paraclinoid region and porus acusticus. The semicircular dural flap is pulled out with a thread over the anterior clinoid process or the porus acusticus. The flap is extended over the underlying structures with a tapered spatula to create adequate space for drilling the bone. The site for drilling was adequately exposed and bone was drilled away smoothly without damaging the underlying vessels and nerves in 10 patients with paraclinoid aneurysms and in seven patients with vestibular schwannomas. This "protective dural flap" method provides wide exposure for drilling, protects the underlying structures, and allows quick inspection during bone resection.
Neurologia medico-chirurgica 09/2003; 43(8):416-8; discussion 418. · 0.61 Impact Factor
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ABSTRACT: Aneurysmal subarachnoid hemorrhage rarely occurs in young adults. The aim of this work was to clarify the clinical characteristics of ruptured aneurysms in young adults in the third and fourth decades of life and to compare these two age groups.
The authors retrospectively investigated 2493 patients who underwent surgical repair for ruptured cerebral aneurysms during a 14-year period (1988-2001). There were 25 patients (1%) in the third decade of life and 106 patients (4.3%) in the fourth decade. In general, favorable outcome was achieved in both groups. There were significant differences in the sizes and locations of aneurysms between the two age groups. Among patients in the fourth decade of life, the aneurysm was large and was located more often on the anterior cerebral artery.
In this study the authors summarize the clinical characteristics of a large series of 131 young adult patients with ruptured cerebral aneurysms. Congenital factors as well as hemodynamic stress may contribute to differences in aneurysm size and location between the two age groups.
Journal of Neurosurgery 09/2003; 99(2):276-9. · 2.96 Impact Factor
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ABSTRACT: The clinical and neuroimaging characteristics of hydrocephalus associated with vestibular schwannoma were retrospectively analyzed to improve the perioperative management of the circulation of cerebrospinal fluid.
A retrospective analysis was performed in 236 patients with unilateral vestibular schwannomas. The patients' ages ranged from 17 to 83 years (mean 53.6 +/- 13.2 years), and the diameters of the tumors the patients harbored ranged from 5 to 60 mm (mean 30.5 +/- 12.7 mm). Hydrocephalus was present before tumor resection in 33 patients (14%) and in six of these patients focal dilation of the sylvian fissures was noted. There was a significant correlation between the incidence of hydrocephalus and tumor size. The incidence of preoperative hydrocephalus among elderly patients (> or = 65 years of age) was 28.6% and that among younger patients (< 65 years of age) was 10.8%. Tumors in elderly patients with hydrocephalus (mean tumor diameter 32.8 +/- 11.7 mm; 12 patients) were significantly smaller than those in younger patients (mean tumor diameter 41.7 +/- 10.9 mm; 21 patients). Among patients with tumors smaller than 30 mm (114 patients), the incidence of hydrocephalus in elderly patients (25%) was 12-fold higher than that in younger patients (2.1%). Six patients with hydrocephalus who had focal dilation of the sylvian fissures were significantly older than 27 patients with hydrocephalus in whom there was no focal dilation. The dilated sylvian fissures collapsed in two patients spontaneously after tumor resection and in the other four patients after shunt placement.
The incidence of associated hydrocephalus is higher in older patients. Communicating hydrocephalus tends to occur in elderly patients. Enlargement of the ventricles with focal dilation of the sylvian fissures should not be misinterpreted as physiological brain atrophy.
Journal of Neurosurgery 06/2003; 98(6):1188-93. · 2.96 Impact Factor
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ABSTRACT: The behavior of brain tissue in cases of arteriovenous malformations (AVMs) is a matter of debate. The authors believe that the local microvascular environment in the AVM bed shares the hemodynamic changes influencing that behavior in one way or another. The purpose of this study was to investigate the microvascular pathological features in the immediate perinidal brain tissue.
This retrospective study was conducted using excised AVM specimens obtained in 35 patients, from which the authors selected 20 specimens that fulfilled the criteria for sufficient brain tissue around the excised nidus. Specimens were stained with hematoxylin and eosin, and the immediate perinidal microvascular environment was examined using light microscopy.
Eighty-five percent of the AVMs studied showed the presence of huge, dilated capillaries, and 65% showed severe congestion of these capillaries. The authors have named these capillaries "giant bed capillaries." In this study capillary bleeding was shown in AVMs, and a pericapillary space was seen around some vessels. The brain parenchyma containing AVMs with these findings proved to be significantly ischemic.
Journal of Neurosurgery 05/2003; 98(4):823-7. · 2.96 Impact Factor
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Journal of Neurosurgery 04/2003; 98(3):643. · 2.96 Impact Factor
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ABSTRACT: Three-dimensional (3D) neuroimages are generally considered useful for neurosurgical practice. Nevertheless, neuroimaging modalities such as 3D digital subtraction angiography and 3D computerized tomography angiography are still insufficient because the resulting images fail to delineate neural structures. Complex neurosurgical procedures are mostly performed in the cerebrospinal fluid (CSF) space of the basal cistern, where vessels and neural structures are present along with the lesion. The magnetic resonance (MR) imaging-derived 3D constructive interference in steady-state (CISS) imaging displays the margin between the CSF and neural structures, vessels, and dura mater in detail, in a two-dimensional fashion. The authors know that volume-rendered 3D CISS images would be more useful for surgery than conventional ones. Although the usefulness of "virtual MR image endoscopy" was reported previously, the endoscopic view is different from the operative field because of the perspective being emphasized. Therefore, to simulate surgical views, the authors made 3D neuroimages from a 3D CISS MR sequence by using an advanced computer workstation. After generating volume images, a cutting method was used in the desired plane to visualize the lesion with reference to a multiplanar reformatted image. The authors call these "real" 3D CISS images, and they are more comparable to the operative field. This newly developed method of producing a real 3D CISS image was used in 30 cases and contributed to the understanding of the relationship between a lesion and surrounding structures before attempting neurosurgical procedures, with minimal invasiveness to the patient.
Journal of Neurosurgery 04/2003; 98(3):625-30. · 2.96 Impact Factor
