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ABSTRACT: We report herein the technical considerations for endoscopic septostomy in a case of hydrocephalus associated with tuberous sclerosis.
A 17-year-old boy presented with visual and gait disturbances. Computed tomography revealed an intraventricular mass obstructing the foramen of Monro bilaterally and marked hydrocephalus. First, we planned a ventriculo-peritoneal shunt with endoscopic septostomy using a biportal approach to resolve the hydrocephalus. Guidance by a rigid endoscope inserted into the anterior horn of the left lateral ventricle allowed us to easily and safely perform septostomy using the fiberscope inserted into the anterior horn of the right lateral ventricle.
A biportal approach such as the dual endoscopic technique is useful in the treatment of complicated intraventricular lesions with loss of midline structures.
min - Minimally Invasive Neurosurgery 05/2009; 52(2):79-82. · 0.70 Impact Factor
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ABSTRACT: The subtemporal transtentorial approach provides excellent exposure of the middle incisural space. A modification of the subtemporal transtentorial approach with use of a partial mastoidectomy is presented to avoid damage to the temporal lobe as a result of retraction as well as damage to venous structures.
Four patients, one with a superior cerebellar artery aneurysm, one with a metastatic tumor in the midbrain, one with a tentorial meningioma, and one with a tentorial schwannoma were treated with the present approach. After subtemporal craniotomy, all of the cortical bone overlying the mastoid was removed. The mastoid air cells were drilled down, and the upper part of Trautman's triangle was exposed above the level of the lateral semicircular canal. The presigmoid dura and the temporal dura were opened and connected by incising the superior petrosal sinus. The cerebellar tentorium was incised in a lateral-medial direction along the angle of the tentorium.
In each case, the tentorium was incised with minimal retraction of the temporal lobe without any damage to the temporal lobe, or venous structures. The present approach yielded excellent visualization of the lesion and adjacent neurovascular structures. In 3 of 4 cases, the lesions were successfully treated. In the patient with a tentorial schwannoma extending from the middle to posterior incisural space, the extreme lateral supracerebellar-infratentorial approach was combined with the present approach.
Although additional partial mastoidectomy is time-consuming, it reduces the risk of damage to the temporal lobe as a result of retraction as well as damage to venous structures.
min - Minimally Invasive Neurosurgery 01/2009; 51(6):340-4. · 0.70 Impact Factor
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ABSTRACT: The neuroendoscope is playing an increasing role in the diagnosis and treatment of several types of lesions, in particular in the ventricular system. Hydrocephalus associated with intraventricular hemorrhage (IVH) is a good indication for neuroendoscopic surgery. We describe herein our experiences with 17 cases of IVH combined with hydrocephalus treated using a neuroendoscope.
The subjects comprised 17 patients with IVH combined with hydrocephalus treated in our department, including cases of thalamic hemorrhage (n=10), caudate hemorrhage (n=5), moya-moya disease (n=1), and dural arteriovenous fistula (n=1). We used a flexible fiberscope that was inserted into the anterior horn of the lateral ventricle. Hematoma was easily evacuated through the working channel of the neuroendoscope by manual maneuvers. Hematomas in the third ventricle, aqueduct and fourth ventricle could also be evacuated. With the addition of septostomy, hematomas in the contralateral lateral ventricle could also be evacuated.
All patients underwent successful procedures with good outcomes. No permanent morbidity and mortality was associated with any neuroendoscopic procedures. Shunt insertion was required in 3 cases due to malabsorption of cerebrospinal fluid (CSF) in the chronic stage.
Neuroendoscopic procedures with a flexible fiberscope for the removal of IVH allow resolution of the disturbed CSF circulation. This procedure improves the safety and accuracy of treatment for IVH combined with hydrocephalus.
min - Minimally Invasive Neurosurgery 01/2009; 51(6):345-9. · 0.70 Impact Factor
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ABSTRACT: Selective venous sampling from the posterior portion of the cavernous sinus (CS) is recommended for the diagnosis of Cushing disease, because samples from the posterior portion yield higher adrenocorticotropic hormone (ACTH) levels than those from the anterior and middle portions. We prospectively assessed this intracavernous gradient of ACTH level to determine which site in the CS yields adequate sampling.
In 5 patients with Cushing syndrome, cavernous sinography was performed to assess drainage pattern of the CS. Sampling was performed from the anterior, middle, and posterior parts of the CS, inferior petrosal sinus (IPS), and the peripheral vein. The ratio of the concentration in CS and IPS to that in peripheral blood plasma (C/P ratio) was calculated.
Cavernous sinography showed that the main drainage route was the IPS in 6 sides and that the pterygoid plexus (PP) was developed to the same extent as the IPS in 3 sides. In 1 patient, the CS drained mainly to the PP. In 1 patient with an ectopic lesion, no increase in ACTH level was detected. In 3 of 4 patients with Cushing disease, the highest C/P ratio was obtained from the posterior portion. In 1 patient whose main drainage route was the PP, the highest C/P ratio was obtained from the anterior portion. In this case, sampling data from the posterior portion and the IPS yielded false-negative results.
Understanding the drainage patterns of the CS is essential for interpretation of sampling data from the CS and avoiding false-negative results.
American Journal of Neuroradiology 02/2008; 29(1):69-72. · 2.93 Impact Factor
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ABSTRACT: In a previous study, we found that thrombin induced proliferation of TM-1 and T98G human glioma cells and that the mitogenic effect was abolished by hirudin.
We investigated thrombin's effects on the proliferation of A172 human glioblastoma cells and the induction of growth factors. Furthermore, we examined whether or not the expression of heparin cofactor II (HCII) in A172 cells using adenovirus vector could suppress thrombin's effects.
The effect of thrombin on cell proliferation was assessed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. The amount of growth factors in the conditioned medium was measured by enzyme-linked immunosorbent assay. The level of platelet-derived growth factor (PDGF)-B mRNA was assessed by reverse transcriptase-polymerase chain reaction analysis.
Thrombin-induced proliferation of A172 cells primarily depended on the enhanced secretion of PDGF-AB by thrombin. The action of thrombin depended on its proteolytic activity. However, thrombin-induced PDGF-AB secretion was not abolished by anti-protease-activated receptor (PAR) antibody. The PAR-1 agonist peptide had no effect on cell growth and PDGF-AB levels. Thrombin did not increase PDGF-B gene expression. Expression of HCII effectively suppressed thrombin-induced PDGF-AB release.
These results indicate that thrombin may play an important role in the proliferation of A172 cells by inducing PDGF-AB secretion and that thrombin's action is mediated by its proteolytic activity. Inhibition of thrombin's proteolytic activity may be a new therapeutic method for gliomas.
Journal of Thrombosis and Haemostasis 12/2007; 5(11):2219-26. · 5.73 Impact Factor
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ABSTRACT: Anatomical connections of the insular cortex suggest its involvement in cognition, emotion, memory, and behavioral manifestation. However, there have been few neurophysiological studies on the insular cortex in primates, in relation to such higher cognitive functions. In the present study, neural activity was recorded from the monkey insular cortex during performance of a delayed-response delayed-reward go/nogo task. In this task, visual stimuli indicating go or nogo responses associated with reward (reward trials) and with no reward (no-reward trials) were presented after eye fixation. In the reward trials, the monkey was required to release a button during presentation of the 2nd visual stimuli after a delay period (delay 1). Then, a juice reward was delivered after another delay (delay 2). The results indicated that the neurons responding in each epoch of the task were topographically localized within the insular cortex, consistent with the previous anatomical studies indicating topographical distributions of afferent inputs from other subcortical and cortical sensory areas. Furthermore, some insular neurons 1) nonspecifically responded to the visual cues and during fixation; 2) responded to the visual cues predicting reward and during the delay period before reward delivery; 3) responded differentially in go/nogo trials during the delay 2; and 4) responded around button manipulation. The observed patterns of insular-neuron responses and the correspondence of their topographical localization to those in previous anatomical studies suggest that the insular cortex is involved in attention- and reward-related functions and might monitor and integrate activities of other brain regions during cognition and behavioral manifestation.
Neuroscience 01/2007; 143(2):627-39. · 3.38 Impact Factor
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ABSTRACT: In elderly patients with aneurysmal subarachnoid hemorrhage (SAH), complications including vasosopasm, subdural effusion, and late hydrocephalus, are liable to occur even after aneurysmal surgery. We examined prospectively the efficacy of arachnoid plasty using fibrin glue membrane during surgery of ruptured aneurysms in the elderly patients for preventing complications. The effects on the modified Rankin scale (mRS) and the Glasgow outcome scale (GOS) 3 months after SAH were noted.
Total of 31 patients aged more than 70 years selected from a consecutive series of patients with aneurysmal SAH, were divided into two groups alternately, a group with arachnoid plasty (n = 16) and a control group without arachnoid plasty (n = 15). Statistical analyses were performed to assess relationships among various clinical and neuroradiological variables, especially between arachnoid plasty and occurrence of symptomatic vasospasm, subdural effusion, late hydrocephalus, or outcome such as mRS and GOS 3 months after onset.
Statistical analyses revealed that arachnoid plasty were associated with late hydrocephalus and subdural effusion negatively, but with better mRS at 3 months after SAH. A tendency to be associated with less frequent symptomatic vasospasm was also noted.
Arachnoid plasty using fibrin glue is suggested to be effective in preventing complications associated with SAH and aneurysmal surgery. A better outcome in the elderly patients can be achieved.
Acta Neurochirurgica 07/2006; 148(6):627-31; discussion 631. · 1.52 Impact Factor
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ABSTRACT: Emergency revascularization of acute carotid artery occlusion is still controversial.We treated 15 patients (13 men and two women, mean age of 67.3 years) with acute atherosclerotic carotid occlusion by endovascular procedures and evaluated the usefulness of this treatment. All of the patients were evaluated with emergency MRI and MRA before treatment. Intracranial tandem arterial occlusion due to distal embolism was observed in nine patients, and contralateral carotid stenosis (> 70%) was observed in seven. The mean NIHSS score of the patients was 15.4 +/- 7.4 (mean +/- SD) before treatment. Treatment modality included local intraarterial fibrinolysis (LIF), percutaneous transluminal angioplasty (PTA), and carotid artery stenting (CAS). A protective balloon was successfully placed in the distal carotid artery through the plaque before recanalization in seven patients. Three patients were treated with LIF+PTA, five with PTA+CAS, six with LIF+PTA+CAS, and one with PTA only. Successful recanalization of the carotid artery was obtained in 14 of the 15 patients, and distal tandem middle cerebral artery occlusion was also successfully recanalized in eight of the nine patients. GOS was four or five in eight patients (good outcome group) and 1-3 in seven patients (poor outcome group). Mean NIHSS score of the 15 patients was (6.9 +/- 7.4) after treatment. Preoperative NIHSS score (10.3 +/- 7.4) in the good outcome group was significantly lower than that (21.3 +/- 5.4) in the poor outcome group. The protective balloon technique, PTA with stenting, seems to be useful for acute revascularization of urgent carotid occlusion. Simultaneous treatment of the intracranial tandem occlusive lesion is essential to achieve good clini-cal results. Patients with acute carotid occlusion with NIHSS scores of less than 16 could be good candidates for this advanced treatment.
Interventional Neuroradiology 01/2006; 12(Suppl 1):233-40. · 0.56 Impact Factor
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ABSTRACT: Neuro-endoscopy is playing a greater role in the diagnosis and treatment of several types of lesions, especially in the ventricular system. However, surgical planning and intraoperative orientation during endoscopic surgery are sometimes difficult. The efficacy of a neurosurgical navigation system using three-dimensional computer graphics of magnetic resonance (MR) images in neuro-endoscopic surgery was evaluated in this study.
We have developed a navigational endoscopic system designed to monitor the tip and direction of the endoscope, with the mirror marker of the navigation connected to a rigid endoscope. Eight patients, 3 cases of aqueductal stenting for isolated fourth ventricle, 3 cases of cystostomy for ependymal cyst, 1 case of septostomy for isolated lateral ventricle, and 1 case of ventricular tap in narrow ventricles, underwent endoscopic surgery using the present system.
All patients underwent successful procedures with good outcomes. The present system was very useful in the cases of an accurate ventricular tap in narrow ventricles, identification of anatomic structures, and determining the appropriate route to the target point.
This navigational endoscopic system improved the safety and accuracy of neuro-endoscopic surgery.
min - Minimally Invasive Neurosurgery 09/2005; 48(4):197-201. · 0.70 Impact Factor
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European Neurology 02/2005; 53(1):38-9. · 1.81 Impact Factor
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ABSTRACT: In this study the hemodynamic status and treatment modality of aggressive dural arteriovenous fistulas (dAVFs) was evaluated. Of 145 intracranial dAVFs treated in our clinic, there were 38 aggressive lesions presenting with hemorrhage, infarction, seizures, and symptoms of increased intracranial pressure. They included 3 (5% of all cavernous sinus lesions) cavernous sinus, 24 (44%) transverse-sigmoid and superior sagittal sinus, and 11 (46%) direct cortical types of dAVFs. Of these 38 aggressive lesions, retrograde leptomeningeal venous drainage was disclosed in 35 lesions, and retrograde sinus drainage in 3. Eighteen cases were treated only with endovascular procedures, 7 with surgical interventions, and 13 with combined endovascular and surgical procedures. Angiographic results were complete obliteration in 66% of the cases, subtotal and partial obliteration in 34%. Clinical outcome was GR (good recovery) in 58% of cases, MD (moderate disability) in 18%, SD (severe disability) in 13%, VS (vegetative state) in 8%, and D (death) (due to acute cardiac infarction) in 3%. Symptomatic procedural complication occurred in 3 cases. In conclusion, aggressive dural AVF resulted from retrograde leptomeningeal venous drainage. Combined surgical and endovascular treatment played the leading part in the management of this aggressive type of lesion.
Acta neurochirurgica. Supplement 02/2005; 94:123-6.
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ABSTRACT: The surgical anatomy of structures surrounding the anterior clinoid process (ACP) was examined in 39 cadavers to enable safe performance of selective extradural anterior clinoidectomy.
The lateral portion of the optic canal (OC) at the end of the orbit was defined as point A, and the lateral margin of the dural insertion into the superior orbital fissure (SOF) as B. A vertical line from A to the lateral margin of the ACP was assumed to define a crossing, defined as C. Distances between A and B, C and B, and C and A were measured. The length and width of OC and the optic strut were also measured.
The mean distances between A and B, C and B, and C and A were 11.8, 8.9 and 6.3 mm, respectively. The mean length and width of OC were 8.9 and 5.7 mm, and those of the optic strut 5.4 and 2.4 mm, respectively.
We propose a modified, efficient procedure for selective extradural anterior clinoidectomy, as follows. Drilling is started from the point approximately 9 mm posterior to the lateral margin of the dural insertion into the SOP, and pointed medially in the direction with a right angle to the lateral margin of the ACP. After drilling about 6 mm to reach the lateral border of the OC, unroofing of the OC is carried out to remove the ACP en bloc by fracturing of the optic strut. Using the present procedure, the distance of drilling of the lesser wing of the sphenoid bone is minimized.
min - Minimally Invasive Neurosurgery 01/2005; 47(6):355-8. · 0.70 Impact Factor
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ABSTRACT: Neuronavigation has become an effective therapeutic modality and is used routinely for intra-axial tumor removal. This retrospective study was conducted to evaluate the clinical impact of neuronavigation and image-guided extensive resection for adult patients with supratentorial malignant astrocytomas. Between 1990 and 2002, 76 adult patients with pathologically confirmed malignant astrocytomas underwent craniotomy and removal of the tumors at the Toyama Medical and Pharmaceutical University Hospital. Of these 76 patients, 42 were treated using neuronavigation with conventional microneurosurgery and the other 34 were treated with conventional microneurosurgery alone. Postoperative early MRI with contrast enhancement was done, and gross total resection was defined as the complete absence of residual tumor. Survival time was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from the Cox proportional hazards model. In univariate analysis, age (< 65), grade 3, preoperative KPS (>/= 80), use of neuronavigation, and gross total resection were significantly associated with longer survival. However, when the data were submitted to multivariate analysis, grade 3, preoperative KPS (>/= 80), and gross total resection were independent prognostic factors. The median survival periods of patients receiving gross total resection (vs. partial resection) and neuronavigation (vs. no neuronavigation) were 16 (vs. 9) months and 16 (vs. 10) months, respectively. The percentage of a gross total resection was significantly higher in the neuronavigation group compared to that in the no-navigation group (64.3 % vs. 38.2 %, p < 0.05). Neurological deterioration occurred in 4 of 42 (9.5 %) and in 6 of 34 (17.6 %) patients after surgery with neuronavigation and surgery without neuronavigation, respectively, although this difference was not statistically significant. Our results showed that neuronavigation increases the radicality in the resection of malignant astrocytomas and is objectively useful for improving survival time.
min - Minimally Invasive Neurosurgery 11/2004; 47(5):278-83. · 0.70 Impact Factor
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ABSTRACT: A 13-year-old female is presented. When she was six years old, she had fallen, holding wooden chopsticks and got stuck with a chopstick in the right upper eyelid. She was brought to a physician immediately, but a residual foreign body was missed and no particular symptom had developed during 7 years. She visited our department with fever and headache, and a brain abscess and an intracranial foreign body were found on computed tomography (CT) and magnetic resonance image (MRI) 7 years after the penetrating injury. She underwent removal of the object and abscess by craniotomy and recovered without neurological abnormalities. Since intracranial retained wooden foreign bodies frequently cause delayed complications of severe central nervous system infection, surgical removal is necessary even in the absence of symptoms.
Acta Neurochirurgica 09/2004; 146(8):847-50. · 1.52 Impact Factor
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ABSTRACT: Neuronal degeneration within the brainstem has been reported in patients with impaired postural stability. However, the functional significance of these abnormalities is unknown at present. In the present study, we evaluated the relationship between the presence of pontine lacunae and postural stability measured by stabilometry. A total of 209 consecutive patients without neurological signs were divided into three groups according to the territory of lacunae on magnetic resonance imaging: (1) non-lacunar group, (2) pontine lacunar group, and (3) non-pontine lacunar group. Stabilometry was performed and statokinesigram measures including each Romberg quotient were compared among the three groups. Using multivariate analysis, postural stability was found to be disturbed in the pontine lacunar group compared with the other groups. The data of stabilometry in this group were compatible with disturbance of the central controlling system for keeping postural stability. Pontine lacuna is associated with patients with postural instability. This result may be related to the deterioration of the central coordination system for posture and locomotion.
European Neurology 02/2004; 51(3):138-43. · 1.81 Impact Factor
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ABSTRACT: Indices of the corpus callosum with normal aging and their sex differences were elucidated using quantitative MRI. We studied 94 Japanese men (mean+/-SD 57.3+/-20.8 years, range 6-90 years) and 111 Japanese women (mean+/-SD 61.2+/-17.6 years, range 9-86 years) who had no intracranial lesions on MRI and no history of neurological illness. The widths of the rostrum, body and splenium, the anterior to posterior length, and the maximum height in the midsagittal image were selected for measurement. The Evans index, which is the relative ratio of lateral ventricle expansion, and the maximum width of the third ventricle in the axial image were also estimated for comparison. The widths of rostrum, body and splenium of the corpus callosum became thinner with age. Conversely, the anterior to posterior length and the maximum height of the corpus callosum increased with age. The ratio of the width of the body to the length of the corpus callosum and the ratio of the width of the body to the height of the corpus callosum are best correlated with age. No sex differences in regional size of corpus callosum, including these two ratios, were observed in any raw measures, although ventricular indices were larger in men than women. Evaluation of the ratio of the width of the body to its length and the ratio of the width of the body to its height may enable accurate estimation of normal or pathological changes of the corpus callosum. Aging and pathological atrophy of corpus callosum can be evaluated without any adjustment for gender.
Neuroradiology 09/2003; 45(8):513-8. · 2.82 Impact Factor
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ABSTRACT: Hemiplegia is a rare complication accompanied with hypoglycemia. We reported three cases of hypoglycemic hemiplegia (HH). Case 1: A 74-year-old female had medication for diabetes mellitus (DM). She had right hemiplegia and aphasia. Case 2: A 72-year-old male had DM, and was admitted to our hospital having loss of consciousness and right hemiplegia. Case 3: An 82-year-old female suffered from consciousness disturbance with tetraplegia, and had left hemiparesis later. She had no DM, but suffered from iatrogenic hypoglycemia. The brain CT of these three cases showed atrophy, and MRI demonstrated multiple infarction. The angiography of case 1 showed the stenosis of bilateral internal carotid artery and the origin of the left vertebral artery. The angiography of case 2 showed severe stenosis of the left internal carotid artery. The cases above had hypoglycemia at admission. The value of the case 1 was 48 mg/dl, case 2 was 35 mg/dl and case 3 was 38 mg/dl. But these symptoms of the three cases disappeared rapidly after glucose infusion. The literature regarding HH was reviewed, and the pathogenesis was discussed. We emphasize the importance of checking blood sugar levels for the emerging patients with hemiplegia, because it is difficult to discriminate by clinical history or neurological findings.
Nō to shinkei = Brain and nerve 01/2002; 53(12):1135-9.
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ABSTRACT: A 55-year-old woman presented with fever and a stiff neck due to an intracranial poorly differentiated carcinoma at the right cerebellopontine angle. The patient suffered from typical trigeminal pain and had undergone a removal of the right cerebellopontine angle epidermoid 13 years before at another hospital. On admission, MRI imaging showed a lesion at the right cerebellopontine angle with marked contrast enhancement. Partial removal of the tumor was achieved. A histological examination of the tumor showed a poorly differentiated carcinoma accompanied by typical desquamated tissue of the epidermoid. The patient died 3 months after the operation because of aggressive meningeal carcinomatosis.
Journal of Clinical Neuroscience 12/2001; 8(6):572-4. · 1.25 Impact Factor
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ABSTRACT: No marker that predicts accurately the time of occurrence of cerebral vasospasm due to subarachnoid hemorrhage (SAH) has been reported. In the present study, membrane-bound tissue factor (mTF) and myelin basic protein (MBP) concentrations in cerebrospinal fluid (CSF) were evaluated as a predictor of the time of occurrence of cerebral vasospasm. The mTF and MBP concentrations were measured in the CSF from 28 patients with SAH due to ruptured aneurysm. Serial assays were performed from day 4 to day 14 after SAH. CSF mTF and MBP concentrations from days 5 to 9 correlated with the volume of cerebral infarction due to vasospasm and outcome three months after SAH. From the serial assays, CSF mTF measurements predicted the time of occurrence and severity and irreversibility of symptoms due to vasospasm. In conclusion, CSF mTF is predictive of the occurrence and the recovery of cerebral vasospasm, while CSF MBP is only an indicator of severity of brain damage due to vasospasm.
Neurological Research 11/2001; 23(7):715-20. · 1.52 Impact Factor
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ABSTRACT: We reported a rare case of craniopharyngioma with chemical meningitis due to spontaneous rupture of the tumor. A 50-year-old woman was admitted with high fever, headache, and nausea. On physical examination, she had nuchal rigidity. The examination of her cerebral spinal fluid(CSF) revealed pleocytosis(mononuclear cell dominant), low value of glucose level and high content of protein. The feature of her CSF findings suggested tuberculosis or fungal meningitis, but bacteriologic culture of the CSF was negative. The CT scan showed an isodensity mass in the suprasellar region and a spotty calcification in the third ventricle. The MRI with gadolinium enhancement suggested that the tumor must be craniopharyngioma and that meningitis was a type of chemical meningitis due to spontaneous rupture of craniopharyngioma. The corticosteroid therapy was rather effective to the symptoms of fever and headache. Then the operation was performed by neurosurgeons, and the diagnosis of craniopharyngioma was pathologically confirmed. Spontaneous rupture of craniopharyngioma rarely occurred and was followed by chemical meningitis. This case was an extremely rare condition that presented with chemical meningitis as an initial symptom.
Nō to shinkei = Brain and nerve 11/2001; 53(10):957-60.
