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ABSTRACT: A 32-year-old man presented with a rapidly progressive decrease in visual acuity and diplopia. Magnetic resonance imaging (MRI) revealed a suprasellar cystic mass extending to the upper part of the clivus. The content of this cyst showed a slightly higher signal intensity than that of his cerebrospinal fluid (CSF) on T1-weighted images. The cyst stretched the pituitary stalk, but a normal pituitary signal was observed. The cyst wall was maximally resected under neuroendoscopy, which yielded fluid contents that were white and mucous like, with a carcinoembryonic antigen (CEA) level 1,400 ng/ml or higher. On light microscopy, one to two layers of epithelial cells with cylindrical nuclei on loose connective tissue lined the cyst cavity. These cells were positive for periodic acid-Schiff, CEA, and cytokeratin 7 and negative for cytokeratin 20. On electron microscopy, epithelial cells showed many short microvilli with coating material. The cytoplasm was rich in electron-dense material, and dense intercellular adhesion was observed, but neither goblet cells nor cilia were present. On the basis of MRI features, cytokeratin expression patterns and electron microscopic findings, the patient was considered to have a suprasellar endodermal cyst derived from Seessel's pouch.
Brain Tumor Pathology 07/2012; · 1.19 Impact Factor
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Clinical neurology and neurosurgery 03/2012; 114(7):1062-5. · 1.30 Impact Factor
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Naoto Kanesaka,
Ryuji Mikami,
Hidetsugu Nakayama,
Sachika Nogi,
Yu Tajima, Nobuyuki Nakajima,
Jun Wada,
Tamotsu Miki,
Jou Haraoka,
Mitsuru Okubo,
Shinji Sugahara,
Koichi Tokuuye
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ABSTRACT: To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) for craniopharyngioma.
Between 1999 and 2005, 16 patients with craniopharyngioma were referred to Tokyo Medical University Hospital. They received FSRT alone after histologic confirmation by needle biopsy and underwent cyst drainage via endoscopy. The median prescription dose fraction was 30 Gy in six fractions. All patients except 1 were followed up until December 2009 or death.
The median follow-up period was 52 months (range, 4-117 months). Of the 17 patients, 3 experienced recurrence 4 to 71 months after FSRT. The 3-year local control rate was 82.4%. One patient died of thyroid cancer, and the 3-year survival rate was 94.1%. Eight patients had improved visual fields at a median of 2.5 months after FSRT, but hormonal functions did not improve in any patient.
FSRT after cyst drainage seems to be safe and effective for patients with craniopharyngiomas, and it may be a safe alternative to surgery.
International journal of radiation oncology, biology, physics 06/2011; 82(4):1356-60. · 4.59 Impact Factor
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ABSTRACT: We developed an image-guided robot system to provide mechanical assistance for skull base drilling, which is performed to gain access for some neurosurgical interventions, such as tumour resection. The motivation for introducing this robot was to improve safety by preventing the surgeon from accidentally damaging critical neurovascular structures during the drilling procedure.
We integrated a Stealthstation navigation system, a NeuroMate robotic arm with a six-degree-of-freedom force sensor, and the 3D Slicer visualization software to allow the robotic arm to be used in a navigated, cooperatively-controlled fashion by the surgeon. We employed virtual fixtures to constrain the motion of the robot-held cutting tool, so that it remained in the safe zone that was defined on a preoperative CT scan.
We performed experiments on both foam skull and cadaver heads. The results for foam blocks cut using different registrations yielded an average placement error of 0.6 mm and an average dimensional error of 0.6 mm. We drilled the posterior porus acusticus in three cadaver heads and concluded that the robot-assisted procedure is clinically feasible and provides some ergonomic benefits, such as stabilizing the drill. We obtained postoperative CT scans of the cadaver heads to assess the accuracy and found that some bone outside the virtual fixture boundary was cut. The typical overcut was 1-2 mm, with a maximum overcut of about 3 mm.
The image-guided cooperatively-controlled robot system can improve the safety and ergonomics of skull base drilling by stabilizing the drill and enforcing virtual fixtures to protect critical neurovascular structures. The next step is to improve the accuracy so that the overcut can be reduced to a more clinically acceptable value of about 1 mm.
International Journal of Medical Robotics and Computer Assisted Surgery 10/2008; 4(4):321-30. · 1.59 Impact Factor
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ABSTRACT: We created an image-guided robot system to assist with skull base drilling by integrating a robot, a commercial navigation system, and an open source visualization platform. The objective of this procedure is to create a cavity in the skull base to allow access for neurosurgical interventions. The motivation for introducing an image-guided robot is to improve safety by preventing the surgeon from accidentally damaging critical structures during the drilling procedure. Our approach is to attach the cutting tool to the robot end-effector and operate the robot in a cooperative control mode, where robot motion is determined from the forces and torques applied by the surgeon. We employ "virtual fixtures" to constrain the motion of the cutting tool so that it remains in the safe zone that was defined on a preoperative CT scan. This paper presents the system design and the results of phantom and cadaveric experiments. Both experiments have demonstrated the feasibility of the system, with average overcut error at about 1 mm and maximum errors at 2.5 mm.
Studies in health technology and informatics 02/2008; 132:198-203.
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ABSTRACT: Virtual endoscopic simulations using volume rendering (VR) have been proposed as a tool for training and understanding intraventricular anatomy. It is not known whether surface rendering (SR), an alternative to VR, can visualize intraventricular and subependymal structures better and thus making the virtual endoscope more useful for simulating the intraventricular endoscopy. We sought to develop SR-virtual endoscopy and compared the visibility of anatomical structures in SR and VR using retrospective cases.
Fourteen patients who underwent endoscopic intraventricular surgery of third ventricle enrolled the study. SR-virtual endoscopy module was developed in open-source software 3D Slicer and virtual endoscopic scenes from the retrospective cases were created. VR virtual endoscopy of the same cases was prepared in commercial software. Three neurosurgeons scored the visibility of substructures in lateral and third ventricle, arteries, cranial nerves, and other lesions Results: We found that VR and SR-virtual endoscopy performed similarly in visualization of substructures in lateral and third ventricle (not significant statistically). However, the SR was statistically significantly better in visualizing subependymal arteries, cranial nerves, and other lesions (p<0.05, respectively).
We concluded that SR-virtual endoscopy is a promising tool to visualize critical anatomical structures in simulated endoscopic intraventricular surgery. The results lead us to propose a hybrid technique of volume and surface rendering to balance the strength of surface rendering alone in visualizing arteries, nerves and lesions, with fast volume rendering of third and lateral ventricles.
NeuroImage 01/2007; 37 Suppl 1:S89-99. · 5.89 Impact Factor
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The Journal of trauma 11/2006; 61(4):985-9. · 2.48 Impact Factor
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ABSTRACT: A 48-year-old woman with a history of viral influenza infection was admitted with rapidly progressive numbness and weakness of the right extremities. On admission, general physical examination revealed no abnormality. Cerebrospinal fluid analysis showed no abnormal findings. Brain computed tomography and magnetic resonance imaging showed an open ring-like enhanced lesion in the white matter of the right parietal lobe with massive perifocal edema. Cerebral angiography showed no tumor staining and thallium-201 single photon emission computed tomography showed no abnormal uptake. The preoperative diagnosis was malignant glioma and partial resection was performed. Histological examination showed perivascular accumulation of small lymphocytes and a large number of macrophages with reactive astrocytes. Phagocytosis of myelin was observed in the macrophages and nuclear fragmentation in the reactive astrocytes. The histological diagnosis was acute inflammatory demyelinating disease. After therapy with methylprednisolone, her neurological symptoms improved gradually and no relapse occurred during 18 months of follow up. Tumor-like masses of demyelination may occupy an intermediate position between acute multiple sclerosis and postinfectious encephalitis. Open ring sign may be a pathognomonic feature of these lesions.
Neurologia medico-chirurgica 08/2006; 46(7):353-7. · 0.61 Impact Factor
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ABSTRACT: Since there is no current consensus on the diagnostic standards or surgical indications for symptomatic cysts of the septum pellucidum (CSP), we presented our experience treating such cases with neuroendoscopic surgery in order to possibly make a contribution to the attainment of such a consensus.
In the last 5 years, we effectively treated 5 patients (4 males and 1 female) with CSP by neuroendoscopic surgery. The 3 congenital cases were young: 9, 14, and 29 years old. The 2 secondary cases were adults aged 51 and 65 years old. We were able to fenestrate, and biopsy for pathological analysis, the cyst walls of symptomatic CSP using a minimally invasive neuroendoscopic technique, with postoperative improvement in compression of adjacent structures, as well as clinical signs.
It is necessary to consider the overall picture including clinical signs, progress of the condition, intracranial pressure, and cerebral circulation, in deciding whether surgery is indicated. Neuroendoscopic surgery is an effective, optimal, and convenient therapeutic modality for symptomatic CSP.
Child s Nervous System 06/2005; 21(5):372-81. · 1.54 Impact Factor
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Shigeto Kobayashi,
Tetsuro Yano,
Yoshifuji Matsumoto,
Fujio Numano, Nobuyuki Nakajima,
Keishu Yasuda,
Chikao Yutani,
Toshiko Nakayama,
Akiko Tamakoshi,
Takashi Kawamura,
Yoshiyuki Ohno,
Yutaka Inaba,
Hiroshi Hashimoto
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ABSTRACT: To elucidate epidemiologic and clinical manifestations of Japanese patients with giant cell arteritis (GCA), the first nationwide survey for GCA was conducted in 1998 in Japan.
The first questionnaire on GCA for patients treated in 1997 was sent to 10,717 medical departments in Japan. A total of 177 patients were reported. Among the 177 patients, 66 GCA patients with detailed clinical and epidemiologic features on second survey were analyzed.
Prevalence in patients 50 years of age and older in 1997 was 1.47 per 100,000 population in Japan. The average age at onset was 71.5 years old. The male:female ratio was 1:1.7. The association with permanent and complete visual loss (6.5%), jaw claudication (15.2%), and polymyalgia rheumatica (PMR) (30.3%) were low in frequency compared with those reported from other countries. All patients were treated with corticosteroids. Only 3 (4.5%) patients were reported as deceased due to other causes.
The prevalence of GCA in Japan was revealed to be extremely low compared with other countries. Clinical findings of permanent and complete visual loss, jaw claudication, and PMR were infrequent among Japanese patients with GCA.
Arthritis & Rheumatism 09/2003; 49(4):594-8. · 7.87 Impact Factor
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Nō to shinkei = Brain and nerve 07/2003; 55(6):479-86.
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ABSTRACT: To elucidate histological changes in the pituitary gland and adenomas following radiotherapy, two irradiated pituitary glands and seven irradiated non-functioning adenomas were studied. The latter included four cases with conventional radiation (CR) and three cases with radiosurgery: two with gamma knife radiosurgery (GKR) and one with stereotactic fractionated radiotherapy (SRT). The specimens were obtained 10 months to 10 years (mean 58 months) after the radiotherapy. Irradiated pituitary glands showed diffuse fibrosis in the adenohypophysis, whereas irradiated adenomas showed either mild or no fibrosis in five CR/SRT cases and diffuse thick hyaline deposits in two GKR cases. No necrosis was observed. Stellate-shaped S-100 protein-positive cells were greater in number in the irradiated pituitary glands than in the normal glands. Pituitary cells with dense granular reactivity for mitochondrial protein, cytochrome oxidase, and Mn-SOD, mimicking oncocytes, were greater in number in the irradiated adenohypophysis but did not show any change in cell size. Many irradiated pituitary cells and some irradiated adenoma cells were densely positive with anticytokeratin 1,5,10,14 antibody whereas non-irradiated counterparts were negative. In adenomas, MIB-1 labeling index remained unchanged after the radiation. The results may indicate that radiation-induced fibrosis was associated with an increased number of folliculo-stellate cells, mitochondrial dysfunction, and squamous metaplasia. These findings were prominent in irradiated pituitary cells and may participate in delayed pituitary hypofunction following radiotherapy. In irradiated adenoma cells, similar findings were observed but diffuse fibrosis was absent. The histological changes were more intensive in adenomas following GKR than those following CR.
Neuropathology 04/2002; 22(1):19-25. · 2.02 Impact Factor
