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Yukihiko Sonoda

Publications and source records attributed to Yukihiko Sonoda.

10 recordsLinked to original sources
PubMed2006

[A simple and accurate technique for cranioplasty in skull tumor surgery].

Cranioplasty using methylmethacrylate is a common method in patients with cranial defects. However, it is often difficult to precisely restore a removed cranium. The authors developed a new technique of cranioplasty. In the present study, we first made a cast composed of methylmethacrylate using a bone flap. We then covered the cast with a sheet of wet gauze. The implant was made by applying methylmethacrylate cement onto the gauze. The implant is firmly fixed to the cranium with titanium plates. Five cranioplasties were perfomed using this new technique. All patients achieved excellent cosmetic results with no complications. This technique enables low-cost, easy and cosmetically successful cranioplastic surgery.

Adult↗
PubMed2005

[New development of surgical treatment for malignant brain tumors].

The most important prognosticator for malignant brain tumor patients is the degree of tumor removal. On the other hand, surgical removal should not induce aggravation of the patient performance status. In accordance with the result, surgical planning for glioma should be carefully considered. However, there is no standard guide for preoperative planning to date. However, there is no standard guide for preoperative planning to the present. We attempted to divide gliomas into 5 stages according to the difficulty of the surgery and analyzed the relation between the removal rate and each stage. The results demonstrated that the stage is correlated with the removal rate. This staging might contribute to standardization of glioma surgery. For surgical planning of tumors around the motor area, fiber tractography and magnetoencephalography should be very useful. As an intraoperative examination, monitoring of motor evoked potential is necessary to resect tumors around the motor area. For resection of tumors around the speech area, functional brain mapping under awake surgery is the most reliable method. In addition to these techniques for safe surgery, neuro-navigation and chemical navigation using 5-aminolevulinic acid are used to achieve of the maximum removal rate. Finally, development of preoperative examinations, microsurgical technique, and intraoperative monitoring enabled us to do safer and move sure surgery.

Astrocytoma↗
PubMed2005

[A case of giant cell tumor in atlas].

We report a rare case of giant cell tumor in the atlas. A 50-year-old female presented with severe pain in her right neck and shoulder. The preoperative magnetic resonance images showed a tumor mixed with solid and cystic components in the right side of the atlas. CT scan showed that the anterior and posterior arches of the atlas were destroyed. Preoperative biopsy led to the pathological diagnosis of giant cell tumor with multinuclear giant cells and mononuclear stromal cells. A preoperative vertebral angiogram demonstrated tumor stain supplied from the muscular branches. To reduce intraoperative bleeding, the embolization of the right vertebral artery by GDC was performed before surgical removal. The tumor was subtotally removed following ligation of the right external carotid artery to reduce bleeding of tumor. We used the Olerud cervical system to prevent cervical instability after resection of the tumor. Although the symptoms disappeared completely after surgery, regrowth of tumor was observed in follow-up MRI 4 months after the operation. For this reason, local radiation therapy was performed (50 Gy). Then, the size of the tumor has not changed in the 1.5 years since the operation.

Cervical Atlas↗
PubMed2004

[A rare case of aqueductal stenosis due to venous angioma].

Aqueductal stenosis is induced by widely various causes. These causes include congenital stenosis, tumor or inflammation. Among them vascular malformation is a very rare cause. In this paper we present a rare case of aqueductal stenosis caused by venous angioma. The patient was a 28-year-old female, who suffered from headache and double vision. On admission, CT and MRI showed lateral and third ventricular dilatation not but fourth ventricle, suggested aqueductal stenosis. Gd-DTPA enhanced T1-weighted MR image showed an abnormal draining vein passing through the orifice of the aqueduct. Angiography demonstrated the umbrella sign which was specific sign of the venous angioma. We performed endoscopic third ventriculostomy. Postoperative neuroradiological examination showed shrinkage of the ventricles and the symptom of the patient improved markedly. In the past literatures, five cases of aqueductal stenosis due to venous angioma have been reported. Although venous angioma is congenital, all five cases had been symptomatic at adult stage. Detailed evaluation of pre-and post-operative MRIs suggest that aqueductal stenosis induced enlargement of the lateral and third ventricles, which led narrowing of the suprachiasmatic cistern and the peri-mesencephalic cistern, and downward displacement of medulla and tonsil into the foramen magnum. As a result, hydrocephalus is aggravated gradually.

Adult↗
PubMed2003

Analysis of the extent of astrocytic tumour resection evaluated by magnetic resonance images.

One of the most important prognostic factors in brain tumours is the extent of tumour resection. Its evaluation has been difficult on computed tomography (CT); however, magnetic resonance imaging (MRI) can clearly determine the extent of tumour resection. Using MRI, we analyzed 77 patients with astrocytic tumours that were surgically treated at our department from 1994 to 2001. The tumours were classified into the following types: (a) well-circumscribed: single lesions that can be distinguished from normal brain; (b) localised: single lesions that are localised in one gyrus; and (c) diffuse: other tumours. Our treatment of glioma resection is to use sulcus opening and gyrectomy, a technique based on identification and dissection of the sulcus adjacent to the tumour followed by en bloc tumour resection. Almost total tumour resection (> or =95% resection) was achieved in 76.8% in the well-circumscribed type, 100% in the localised type, and only 10.5% in the diffuse type. Nearly total resection was achieved in 61%, which is considerably more than in the literature of the CT era (10.4-23.5%). The sulcus opening and gyrectomy technique based on MRI achieved radical glioma removal in cases which could be identified by MRI, resulting in a better tumour removal rate than that based on CT.

Adolescent↗
PubMed2003

Overexpression of vascular endothelial growth factor isoforms drives oxygenation and growth but not progression to glioblastoma multiforme in a human model of gliomagenesis.

Vascular endothelial growth factor (VEGF) is thought to promote tumor growth and angiogenesis. Whereas VEGF is up-regulated in only a portion of anaplastic astrocytoma (AA), it is overexpressed in most glioblastoma multiforme (GBM), and the level of expression is correlated with grade of glioma. To explore the possibility that VEGF may act as a driving force in the progression of AA to GBM, the VEGF isoforms VEGF(121) and VEGF(165) were overexpressed in genetically modified, mutant H-Ras-transformed human astrocytes that on intracranial implantation form AA-like tumors. The ability of the VEGF isoforms to stimulate growth, angiogenesis, oxygenation, and the formation of necrotic GBM-like tumors was then monitored. The parental mutant H-Ras-modified astrocytes expressed four times more endogenous VEGF than normal human astrocytes, but on intracranial implantation formed hypovascular, hypoxic, small AA-like tumors. Whereas these modest levels of VEGF overexpression were insufficient to drive oxygenation and GBM formation, an additional 8-fold increase in VEGF expression mediated by retroviral infection with constructs encoding either VEGF (121) or VEGF (165) resulted in cells which, after intracranial implantation, formed tumors that were larger, more vascular, and better oxygenated than those formed by the mutant H-ras parental cells. However, the tumors formed by the cells expressing exogenous VEGF (121) or VEGF (165) retained the phenotype of AA, lacking areas of necrosis that are the hallmark of the GBM phenotype. These results suggest that whereas the VEGF(121) and VEGF(165) isoforms can contribute to glioma vascularization, oxygenation, and growth, they do not in and of themselves drive the formation of the GBM phenotype.

Astrocytes↗
PubMed2003

[A case of cranial fasciitis induced by trauma].

We present a 20-month-old boy with a rapid growing occipital mass after head trauma, that was pathologically diagnosed as cranial fasciitis. Cranial fasciitis, first described as a specific entity by Lauer and Enzinger in 1980, is a benign fibroblastic lesion occurring in children that resembles nodular fasciitis pathologically. Nodular fasciitis also shows benign proliferation of fibroblasts and myofibroblasts in the subcutaneous tissues. This disease was firstly reported in 1955. This lesion is arising in the upper and lower extremities and trunk in adult commonly. The rapid growth, abundant cellularity, and mitotic activity cause these lesions to be misdiagnosed as sarcomas frequently. However, these lesions recur rarely, do not develop metastases, and are readily cured only by surgical excision. Cranial fasciitis is similar to nodular fasciitis in clinical cause and pathology. Therefore cranial fasciitis should be considered a variant of nodular fasciitis, although it differs from noduler fasciitis in its frequent site and age. Cranial fasciitis occurs in skull bone and in childhood. The cause of them are still unknown. However, we speculate on the relationship between head trauma and cranial fasciitis making reference to the fact that 5-15% of nodular fasciitis were caused by trauma. So we investigated this relationship in cranial fasciitis, then 8 cases of 40 cases(20%), that we could trace in the world literatures, had histories of previous head trauma. From this result, head trauma is one of a cause of cranial fasciitis probably.

Craniocerebral Trauma↗
PubMed2003

[A dura-based intracranial schwannoma in the temporal fossa: a case report].

We report a rare case of a dura-based intracranial schwannoma in the temporal fossa. A 77-year-old man admitted to our hospital with a 5 months history of mild recent memory disturbance. Magnetic resonance imaging (MRI) revealed a slight enhanced solid mass with a cystic mass in the right temporal lobe. Preoperative diagnosis was glioma and then total resection was performed by the transsylvian approach. Dense adhesion of the tumor to dura matter of the middle cranial fossa was confirmed during surgery. Microscopic examination of the tumor showed biphasic pattern with cellular Antoni A and hypocellular Antoni B areas. Immunohistochemically, the tumor was positive for S-100, vimentin and Schwann/2E and was negative for GFAP. From these findings, the tumor was diagnosed as a schwannoma arising from the dura matter of the middle fossa. The patient was discharged from our hospital with no neurological deficits. Intracranial schwannomas, which are not associated with cranial nerves, are rare. Our case was classified according to the origin into dura-based intracranial schwannoma. To our knowledge, only 14 cases of dura-based intracranial schwannoma have been reported, mostly in children and young adults. This represents the oldest case in the literature of dura-based intracranial schwannoma.

Aged↗
PubMed2003

[Rosai-Dorfman disease presenting with multiple intracranial and intraspinal masses: a case report].

Rosai-Dorfman disease (RDD), a systemic histioproliferative disorder, was first described by Rosai and Dorfman in 1969. However, only 41 cases involving the central nervous system have been reported. The authors present a rare case of RDD with multiple intracranial and spinal lesions mimicking multiple meningioma. A 59-year-old woman was admitted to our hospital with a history of bilateral visual impairment. MRI demonstrated multiple central nervous system lesions in the suprasellar region, right temporal convexity, left frontal convexity, left cerebello-pontine angle and C5 level of the spinal cord. Preoperative neuro-imaging studies suggested multiple meningioma. Subtotal removal of the suprasellar lesion was performed, followed by gamma knife radiosurgery to the residual lesion and the other intracranial lesions. All intracranial lesions disappeared following gamma knife radiotherapy. The spinal lesion, however, was completely excised one year after the initial operation following the appearance of sensory disturbance. Both intracranial and spinal lesions were diagnosed as RDD on histological examination. No recurrences have been detected on MRI two years after the initial operation. Seeing the good results already achieved by surgical removal of RDD, this case suggests that the combination of surgery and gamma knife radiotherapy might improve further.

Brain Diseases↗