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Deep brain stimulation (DBS) is performed by burr hole surgery. In microelectrode recording by multi-channel parallel probe, because all microelectrodes do not always fit in the burr hole, additional drilling to enlarge the hole is occasionally required, which is time consuming and more invasive. We report a stereotactic burr hole technique to avoid additional drilling, and the efficacy of this novel technique compared with the conventional procedure. Ten patients (20 burr holes) that received DBS were retrospectively analyzed (5 in the conventional burr hole group and 5 in the stereotactic burr hole group). In the stereotactic burr hole technique, the combination of the instrument stop slide of a Leksell frame and the Midas Rex perforator with a 14-mm perforator bit was attached to the instrument carrier slide of the arc in order to trephine under stereoguidance. The efficacy of this technique was assessed by the number of additional drillings. Factors associated with additional drilling were investigated including the angle and skull thickness around the entry points. Four of the 10 burr holes required additional drilling in the conventional burr hole group, whereas no additional drilling was required in the stereotactic burr hole group (p = 0.043). The thicknesses in the additional drilling group were 10.9 ± 0.9 mm compared to 9.1 ± 1.2 mm (p = 0.029) in the non-additional drilling group. There were no differences in the angles between the two groups. The stereotactic burr hole technique contributes to safe and exact DBS, particularly in patients with thick skulls.

Background Camptocormia, a disturbance of posture, is a well-described clinical feature of PD and other parkinsonian syndromes. Previous reports have shown that DBS of the subthalamic nucleus (STN) or globus pallidus internus is effective in treating camptocormia. However, the efficacy of DBS for camptocormia varies. Objective To determine a clinical marker for selecting an appropriate therapy for camptocormia, a disabling manifestation of Parkinson's disease (PD) that has a variable response to systemic and local therapies. Methods We obtained pre-operative lumbar magnetic resonance imaging of 14 consecutive PD patients with camptocormia who underwent subthalamic nucleus deep brain stimulation (STN-DBS) in this retrospective-designed study. Lumbar MRI was performed three to six months prior to the operation. We measured the cross-sectional area (CSA) and width of each participant's paraspinal muscles. Results Four (28.6%) patients were effective (EF), five (35.7%) were partially effective (PE), and five (35.7%) were non-effective (NE) to STN-DBS. The lumbar paraspinal CSA and width were significantly larger in the EF group than in the PE and NE groups. Conclusions The CSA of paraspinal muscles and erector spinae width can be good predictive markers for improving camptocormia in patients with PD after deep brain stimulation.

Spinal cord dissemination (metastasis) of a fourth ventricle ependymoma more than ten years after surgical resection is extremely rare. In this report, we present an unusual case of a fourth ventricle ependymoma with metastasis to the thoracic spinal cord 19 years after the initial therapy, but without local recurrence. A 37 year-old patient underwent gross total resection of a fourth ventricle ependymoma and postoperative radiation therapy to the posterior fossa. Computed tomography (CT) scanning and/or magnetic resonance (MR) imaging performed during follow up examinations, conducted annually for ten years after the therapy, revealed no evidence of local tumor recurrence. However, 19 years after the initial treatment, the patient complained of back pain and gait disturbances. MR imaging revealed an intradural extramedullary tumor at the Th2-5 levels. MR imaging of the brain revealed no local tumor recurrence or intracranial tumor dissemination. Cerebrospinal fluid cytology revealed no presence of tumor cells. Total resection of the spinal cord tumor was performed, and the tumor was diagnosed as an ependymoma. We describe the clinical features of this rare lesion and particularly emphasize the need for long-term follow up, for more than ten years after the initial treatment, in patients with fourth ventricle ependymoma.

We propose a novel super-resolution near-field structure (super-RENS) read-only-memory (ROM) disc with a narrow track pitch using a group tracking technique. The group tracking technique enables the tracking control of an optical disc because it consists of track pitch sizes that are less than the diffraction limit. The group tracking technique to increases capacity in the radial direction of the super-RENS ROM disc. By using this technique, carrier-to-noise ratio (CNR) was obtained at 33 dB and the minimum crosstalk level was -23 dB at the 100 nm pit length. A readout track was selected by controlling the offset level of the tracking error signal in a high definition digital versatile disc (HD-DVD) system. It was confirmed that the capacity of the super-RENS ROM disc with the group tracking structure was improved in the radial direction.

We propose a new thermal lithography technique that utilizes the thermal decomposition of platinum oxide. This technique enables lithography characterized by high resolution, high speed and large writing area (96?cm2). The smallest reproduced feature was 110?nm in diameter, using an optical system consisting of a 405?nm laser beam and an objective lens with numerical aperture (NA) of 0.65. This feature is six times smaller than is achievable by conventional photolithographic techniques. High-speed writing of over 3?m?s?1 was achieved, with 1.5?million nanodots fabricated per second. Furthermore, a high-aspect-ratio structure, with holes with a diameter of 100?nm and depth 500?nm, was realized.

We propose a new lithography technique using thermal decomposition of platinum oxide (PtOx) for high-throughput master disc fabrication. The smallest pit size was evaluated to be 50 nm using a laser wavelength of 405 nm and a numerical aperture (NA) of 0.65; hence, it is one-twelfth the optical spot size. In addition, fabrication of pits with different shapes was examined, and its effects on super-resolution near-field structure (super-RENS) disc properties were studied. The readout signal characteristic evaluated on the basis of carrier-to-noise ratio (CNR) with an elliptical pit was 7 dB larger than that of the round one. The results demonstrated that this high-throughput fabrication technique is also useful for controling the pit shape for CNR improvement of super-resolution readout.

Cervical compressive myelopathy patients sometimes show localized girdle sensation in the mid trunk (so-called false localizing sign). This symptom often confuses physicians, but the clinical features and mechanism of this symptom are still unclear. We investigated the clinical features and possible mechanism. In each of five cases of cervical compressive myelopathy disease with and without mid-truncal girdle sensation, the clinical features, degree and shape of cord compression were analysed. The girdle sensation was expressed as a vague or burning sensation, and was localized with a width of 3 or 4 dermatomes from the T3 to T11 level. There was no correlation between the appearance of the girdle sensation and etiology and level of cervical cord compression. Pyramidal tract signs and disturbance of superficial sensation were observed in all cases. Furthermore, on axial MRI, the midline ventral surface of the cervical cord was remarkably compressed in cases with girdle sensation, as if the compressive lesion entered the anterior medial fissure of the cervical cord. From these findings, this false localizing sign may be caused by severe compression of midline ventral structure of the cervical cord. Ischemia of the thoracic watershed zone of the anterior spinal artery from the compression of the anterior spinal artery at the cervical level might also be considered to be a possible cause.

Continuous drainage of lumbar cerebrospinal fluid (CSF) was analyzed for the preoperative management of patients with aneurysmal subarachnoid hemorrhage (SAH) in 50 consecutive cases of surgically treated aneurysmal SAH. Patients were divided into a lumbar drainage group, in whom continuous lumbar CSF drainage was established for preoperative management, and a non-lumbar drainage group. Rebleeding from the aneurysm during the insertion of the lumbar drainage tube and during continuous lumbar drainage, effect on the control of the systolic blood pressure, and effect on the sedation of the patient were examined. Continuous lumbar CSF drainage significantly decreased the systolic blood pressure. Seven of 17 patients in the non-lumbar drainage group had systolic blood pressure uncontrollable to below 150 mmHg even when a large amount of nicardipine was used, whereas only two of 33 patients had the same problem in the lumbar drainage group. Sedation was better in the patients in the lumbar drainage group with a smaller amount of analgesics. The rebleeding rate was 11.7% among patients in the non-lumbar drainage group, and 9.09% among patients in the lumbar drainage group. No rebleeding occurred during insertion of the lumbar drainage catheter. Continuous lumbar CSF drainage improved control of systolic pressure and sedation, and is a useful method of preoperative management for patients with aneurysmal SAH.

A 59-year-old male presented with a large cholesterol granuloma arising from the frontal sinus manifesting as a large, fluctuated, soft mass in his brow, compressing left eye. Skull radiography showed dilation of the frontal sinus. Computed tomography and magnetic resonance imaging revealed a cystic mass extending into the left orbit and anterior cranial fossa. Gross inspection at the frontal craniotomy showed mucinous, dark green fluid intermingled with shining material. The histological diagnosis was cholesterol granuloma with epithelial lining. Large cholesterol granuloma with facial deformity is always associated with bone and cosmetic problems. Wide opening of the frontal sinus followed by cyst wall removal and plastic repair of the skull is necessary.

For the development and improvement of optical discs, the temperature dependence of the optical properties of the disc component materials is required. The temperature dependence of the complex refractive indices of Sb–Te alloy films was investigated using a spectroscopic ellipsometer in the wavelength range of 250–1700 nm and in the temperature range from room temperature to 300 °C. It was clear that the complex refractive index of Sb–Te alloys at room temperature widely change with their composition and wavelength. It was also found that the real and imaginary parts of the refractive index at a wavelength of 650 nm, which is generally used in optical discs, are decrease as the temperature increases.

Two dielectric materials were added to a super-resolution near-field optical disc structure (super-RENS) to improve the readout durability. PtOx–SiO2 (Pt8.4Si21.1O70.5) layers showed O2 desorption for temperatures above 200 °C and were usable as write-once recording layers. The GeNy interfacial layers located between the Sb75Te25 and (ZnS)85(SiO2)15 layers suppressed degradation in the reflected light intensity from the disc, i.e., maintained the recorded structure as is, to at least 5×104 readout cycles using a recorded pattern designed to accelerate disc deterioration. The carrier-to-noise ratio (CNR) obtained for 100-nm marks (laser wavelength: 405 nm, numerical aperture: 0.65) was about 43 dB. It was possible to readout 2.6×105 cycles before the CNR decreased by 3 dB. This represents an improvement of a factor of 70 over the readout durability of a conventional super-RENS structure.

Metal-free phthalocyanine (C32H18N8) film was sandwiched by ZnS–SiO2 layers, and it was prepared on read-only-memory disc substrate. Super-resolution effect was observed when the readout laser power was 4.4 mW at a disc rotation speed of 6 m/s, and carrier-to-noise ratio of about 40 dB was obtained at 200-nm mark that was 75% size of the resolution limit (laser wavelength = 635 nm, numerical aperture = 0.60). The super-resolution readout was achieved at higher than a threshold laser power (at around 3.0 mW with 6 m/s), and the power shifted as a function of disc rotation speed suggesting that the readout depends on temperature, which is similar to super-resolution near-field structure disc using platinum-oxide recording layer.

We developed a novel simulation program unified by electromagnetic and thermal distributions for a rotating optical disc on the basis of the three-dimensional finite-difference time-domain (FDTD) method. We applied this simulation to super-resolution near-field structure (super-RENS) read-only-memory (ROM) discs and elucidated that the temperature distribution is not only dependent on disc structure and pit shape, but also on incident laser light polarization. We obtained the result that the temperature at the pit became higher than the surrounding temperature for the first time using our simulation program. We believe that our program will aid our understanding of the phenomena behind the super-resolution readout of super-RENS discs.

Objective Appropriate stimulation of the dorsal column is required in order to achieve optimal control over pain by way of spinal cord stimulation (SCS). In this study, we objectively evaluated changes in somatosensory evoked potentials (SEPs) during a collision test in order to investigate whether paresthetic sensation or amount of pain reduction was correlated with the degree of dorsal column stimulation. Materials and Methods We studied 12 patients with intractable pain who underwent permanent SCS implantation. SEP collision was examined while recording the cortical SEP components elicited by posterior tibial nerve stimulation. A positive collision effect was observed when the SEP amplitude was clearly reduced by the SCS. Results Based on the SEP collision findings, the effects of SCS were classified into four patterns: positive collision with pain reduction (Type 1), positive collision without pain reduction (Type 2), negative collision with pain reduction (Type 3), and negative collision without pain reduction (Type 4). Type 1 was observed for well-known diseases in which SCS was very effective, whereas Type 2 was seen in poor candidates for dorsal column stimulation. Patients with poststroke pain exhibited various patterns including types 1, 2, and 3. One patient showed Type 4 patterning, and we recommended further SCS trials before the abandonment of SCS therapy for this patient. Conclusions We show that SEP collision is useful for evaluating the degree of dorsal column stimulation needed as well as in considering factors related to differences between responders and nonresponders to SCS therapy.

Study design Case report of a patient with atlantoaxial subluxation who underwent posterior cervical fixation. Objective To describe a novel approach for the efficient use of a full-scale, 3-dimensional model for preoperative planning and surgery. Summary of background data Instrumented fusion of the cervical spine with screws and rods is indicated for atlantoaxial subluxation. Fatal complications, such as vertebral artery and spinal cord injuries, may occur during screw insertion. Making appropriate connecting rods, after screw insertion, is often time consuming. Therefore, precise preoperative planning and careful intraoperative procedures are required. Methods A 73-year-old male with atlantoaxial subluxation presented with progressive quadriplegia and gait disturbance. Surgery involving a C1 laminectomy and posterior cervical fixation was planned; and a 3D model, allowing visualization of the vertebral artery, was developed. Bilateral C1 and C4 lateral mass screws and C2 pars screws were experimentally inserted into the model. Rods with appropriate curvature were created to obtain rigid screw fixation, and were used during the surgery. Moreover, radiography and computed tomographic images of the instrumented model were analyzed to ensure the proper orientation of the screws. Results During surgery, screw insertion was performed, under fluoroscopic guidance, and compared with the 3D model and its preoperative radiographs. According to the preoperative analysis of the model-computed tomographic images, the direction of the C1 lateral mass screws was changed laterally, and the lengths of the C2 pars screws were shortened to avoid complications. The sterile, prebent rods could be elegantly adapted to the screws without additional bending. The postoperative course was uneventful, and postoperative computed tomographic images showed proper screw positioning. Conclusion Three-dimensional models that allow (1) visualization of the vertebral artery, (2) evaluation of radiological images after screw insertion, and (3) the use of prebent rods during surgery contribute to the safety of the cervical posterior fixation. Level of evidence N/A.

✓ The case of a 40-year-old woman with a mature cystic teratoma in the lateral ventricle is reported. An unusual mobile sediment of radiopaque material in the cyst was identified as grains of calcium carbonate. It was considered to have precipitated from the cystic fluid under specific chemical conditions.

In a 47-year-old woman experiencing pulsatile headache, radiological examination revealed a large right posterior cerebral artery (PCA) aneurysm. Preoperative neurological examination showed bilateral papilledema, but no visual disturbance. Cerebral angiography revealed that the aneurysm originated from the ambient segment of the PCA, and the posterior temporal, calcarine, and parieto-occipital arteries were all branched from the aneurysmal dome. Clipping of the feeding PCA trunk was performed via a left subtemporal approach. As a result of left occipital lobe infarction due to calcarine artery occlusion, right upper quadrant hemianopsia appeared after surgery, as confirmed by Goldman's perimetry. Other cerebral infarctions were identified in the junction between the left posterior internal capsule and thalamus, in the left posterior corpus callosum, and in the posterior base of the left temporal lobe due to the occlusion of the posterolateral thalamoperforating, posterior pericallosal, and posterior temporal arteries, respectively. The aneurysm was thrombosed and headache and papilledema subsided. The patient was able to detect the motion of a subject in a blind field, but consciousness of sight was absent. She was able to unconsciously move her finger toward a small penlight, and insert a paper into a slot with variable angles in the blind field. These phenomena disappeared within 4 months of the surgery. The results to forced choice tasks with figures (circle, cross, square, triangle, and star) and colors (red, blue, yellow, and green) were below chance levels. The present case was thus diagnosed as blindsight type 2 (gnosopsia) associated with awareness, probably due to transient activation of the dorsal "what" pathway among numerous visual processes.

Putting germanium nitride thin-films between Sb-Te and ZnS-SiO2 was effective to improve super-resolution readout durability of a super-RENS disc using PtOx-SiO2 recording layer. 260,000 times readout was possible with CNR over 40 dB.

We report on the temperature dependence of the refractive index and thermal diffusivity for several optical disk materials up to a few hundred degrees °C. A novel system to obtain thermal diffusivity in the films is also introduced.

Neuroleptic malignant syndrome (NMS), also called parkinsonism-hyperpyrexia syndrome (PHS), is a severe, general, sometimes fatal, physical reaction, induced by sudden and strong blockade of dopamine receptors. When subthalamic nucleus (STN)-deep brain stimulation (DBS) is used on patients with Parkinson disease (PD), dopaminergic medications are transiently stopped prior to the procedure, and a reduction in the use of drugs is routinely attempted after the procedure. Although a sudden stop or abrupt reduction of dopaminergic medications may set the stage for NMS/PHS, only three cases have been reported after STN-DBS surgery. Here, we describe a 75-year-old woman with PD who experienced delayed onset, yet fatal, PHS after STN-DBS. Although STN-DBS might prevent or suppress PHS, its protective effect is not always complete. We must be aware that fatal PHS can occur when the use of medication for PD is reduced or altered, even when patients are under continuous STN stimulation.

The occurrence of neurogenic pulmonary edema (NPE) associated with subarachnoid hemorrhage (SAH) due to ruptured aneurysm was analyzed in 48 consecutive patients. Correlations of the location of the aneurysm, clinical grade, amount of subarachnoid clot, and severity of NPE were examined. NPE was observed in 29.4% of all SAH cases, but the incidence was significantly higher in cases of ruptured vertebral artery (VA) aneurysm. Clinical grade, severity of NPE, and deformation of the medulla oblongata were studied in the five cases of ruptured VA aneurysm. Deformation of the ventrolateral medulla oblongata was observed in all patients. Asymmetry index of the medulla oblongata measured on the axial computed tomography scan was correlated with the severity of NPE. Severity of NPE tended to correlate with deformation of the medulla oblongata. NPE associated with ruptured VA aneurysm is caused by deformation of the ventrolateral site of the medulla oblongata by the localized hemorrhage.

A case of brain surface ependymoma is reported here. A 41-year-old woman presented with weakness of the right upper limb. Magnetic resonance imaging revealed a left fronto-parietal cystic tumor with a calcified mural nodule. Total removal of the tumor was performed. This tumor was located within the surface portion of the fronto-parietal parenchyma and was sharply demarcated from the surrounding brain tissue, and there was no continuity with the ventricles. Histological examination of this tumor showed monotonous proliferation of tumor cells with moderate cellularity and occasional mitoses, forming true ependymal rosettes and perivascular pseudorosettes with fibrillary background. A clear cell component resembling oligodendroglioma was partly noted. The tumor cells showed positive immunoreaction for glial fibrillary acid protein and vimentin.

A central nervous system germinoma is curable in most cases by radiotherapy, and most of the tumor mass disappears promptly after 20-30 doses. However, some germinomas take a longer period to vanish completely from magnetic resonance imaging (MRI) or computed tomography (CT) scans. In such cases, the tumor may contain components such as teratoma. The aim of this study was to clarify the nature of the persistence of some germinomas. Five cases of histologically verified germinoma in which radiotherapy was performed to treat residual tumor were selected. The doses of focal radiotherapy and whole brain radiotherapy were 10-20 Gy and 20-34 Gy, respectively. In these cases, correlation was made between the degree of persistence of the tumor when assessed by MRI and the amount of interstitial content, as determined by histology. The histological evaluation, using hematoxylin-eosin stain, silver impregnation and Azan staining was carried out independently of clinical information. The tumor vanished soon after radiotherapy in three cases, but 3-15 months passed before the tumor completely vanished from the MRI scans in the other two cases. The histology of the cases in which the tumor disappeared rapidly was predominantly of large tumor cells and only small amounts of reticulin. However, in the persistent tumors, large amounts of reticulin and vascular components were present. Thus, it is proposed that tumors with a large parenchymal component disappear soon after radiotherapy, whereas tumors composed mainly of interstitial component persist. Long-standing enhancement seen on MRI or CT scans of patients with an intracranial germinoma is indicative of a large amount of interstitial component in the tumor.

An extremely rare case of the primary leiomyosarcoma of the cervical spine presenting as a compression fracture is reported. A 69-year-old man complained of dysesthesia of both hands. A plain radiograph, computed tomography and magnetic resonance imaging of the cervical spine showed a compression fracture of the vertebral body at C7 without the formation of an obvious mass. From radiological findings, the fracture was considered to be caused by an infiltrative vertebral bone tumor. Biopsy of the tumor revealed a leiomyosarcoma, a metastatic tumor being ruled out by a systemic investigation. The patient died of pleural metastasis 6 months later, and an autopsy confirmed the primary site of the tumor as the cervical spine.

A 48-year-old female was stabbed by her husband with a chopstick made of wood in the left temporal region during a quarrel. She suffered laceration of the left temporal scalp. At initial examination, she concealed the assault with a chopstick. Radiography showed no abnormality, so the wound was sutured. One month after the injury, a painless subcutaneous mass appeared in the left temporal region which grew rapidly for 3 months. She was then admitted to our department. Computed tomography (CT) on admission showed a hyperdense area at the center of the mass. This area was hypointense on both T1- and T2-weighted magnetic resonance (MR) images. Temporalis muscle tumor with accompanying central necrosis, old hematoma, and inflammatory granuloma was considered. The mass was totally resected for cosmetic purposes and was found to be wooden foreign body granuloma. High density on CT and hypointensity on both T1- and T2-weighted MR images are characteristic of a chronically retained wooden foreign body in the living body and are useful for detecting wooden foreign bodies in the chronic granulomatous phase.

Tenting of the arachnoid with intact trabeculae to facilitate and maintain rotation of the cord during the resection of ventrally or ventrolaterally located spinal meningiomas is proposed. The arachnoid-trabeculae tenting acts as a self-retaining retractor, and prevents overlapping of the cord onto the tumor due to gravity.

We describe the readout-power dependence of the properties optical readout signals, and discuss the super-resolution mechanism in platinum-oxide super-resolution near-field structure (super-RENS) disks. From the Fourier analysis of a focused spot, it is clear that a low-reflectivity region within the beam spot during readout above the threshold readout power is generated in a special-temperature region, which, in turn, is associated with the readout mechanism. These phenomena suggest that such readout is related to a large change in the optical properties of a phase change layer, as proposed in the ferroelectric catastrophe model.

We describe surface plasmon enhancement by near-field interaction with Ag-scattering centers. By inserting mark trains between two Ag-scattering centers, the near-field signals were further enhanced in a super-resolution near-field structure. Observing the enhancement in more detail, it was found that surface plasmons are generated along the mark trains and are dispersed in a range of 1 µm along the marks and 40–50 nm normal to the multilayer stack.

We describe the optical properties of readout signals from light-scatting-center super-resolution near-field structure disks by a numerical simulation using a three-dimensional finite-difference time-domain method (FDTD). Since the generation process of the near-field readout signals has a relationship between the direction of the mark train and the polarization direction of incident light, the optical properties of readout near-field signals strongly depended on the incident light polarization. It was found that the land & groove structure, and the scattering center size also influenced the readout signals.

Using a silver oxide thin film of a non-magnetic mask layer, the magneto-optical (MO) recording signals were enhanced by surface plasmon. A resolution of less than 170 nm was achieved by the near-field coupling between a light-scattering center generated in the AgO x film and the light polarization of MO marks. The electrical field intensity was also confirmed by a computer-simulation. Optimization of the disk structure and materials, and the effects of readout power were investigated.

The authors report a case of hemophilia B complicated by subacute subdural hematoma after minor head injury, which was successfully managed by surgery and the use of concentrates of plasma factor IX (Konyne).

Eighteen cases of intracranial meningioma that received preoperative or post-operative irradiation with60Cobalt or Linac have been reviewed. Eight patients received preoperative irradiation because their tumours were very large, hypervascular, and surgically not readily accessible. Two angioblastic meningiomas of the haemangiopericytoma type responded well to irradiation and were easily extirpated. One of these developed a local recurrence and metastases to the lungs and liver nine years after surgery. The recurrent intracranial tumour and nodules in the lungs responded well to irradiation. The other six cases of meningiomas of meningothelial, transitional, or haemangioblastoma types, did not improve clinically or radiologically after irradiation. Ten cases received postoperative irradiation because their tumours were only partially removed or were histologically malignant. In all cases irradiation was most effective for recurrent tumours of the haemangiopericytoma type. This study indicates that irradiation is useful in tumours of the haemangiopericytoma type as an adjunct to surgery or for palliation in advanced stages. Irradiation may have been effective in supressing recurrences in two cases of other types of meningioma, although the number of cases is too small to allow any definite conclusion.

A case of a suprasellar epithelial cyst in a 48-year-old man is reported. The cyst was lined with two different types of stratified epithelium: one was two to three or more layers of squamous cells with overlying ciliated columnar cells and goblet cells at the surface and the other was tyical stratified squamous epithelial cells. The tumor was neither a pure Rathke's cleft cyst nor a typical craniopharyngioma but was considered essentially to be a craniopharyngioma with ciliated columnar cells and goblet cells. Thus it might be considered a mixed form of these two tumors. This case indicates the close relationship between craniopharyngiomas and Rathke's cleft cysts.

Epithelial cells composing symptomatic Rathke's cleft cysts were examined electron microscopically in two cases, and the fine structures were compared with those of the mucosa in the normal sphenoid sinus, of the normal choroid plexuses, and of a craniopharyngioma with goblet and ciliated cells. The Rathke's cleft cysts were composed of a single or pseudostratified epithelial layer abutting on the connective tissue. The epithelial cells were of four different kinds of cells, such as goblet, ciliated, flat, and basal cells. The flat cells containing bundles of tonofilaments and desmosomes were the squamous cells. They were present in a single-epithelial layer in both cases. The basal cells were present as small, wedge-shaped cells, even if the number was very small. The epithelial cells in Rathke's cleft cysts were more similar to those of the mucosa in the sphenoid sinus and those of a craniopharyngioma with goblet and ciliated cells than those of the choroid plexus. This study indicates the close relationship between Rathke's cleft cysts and mucosa in the sphenoid sinus or craniopharyngioma with ciliated and goblet cells.

CSF cells in a case of primary reticulum cell sarcoma of the brain with diffuse subarachnoid spreading were examined by 3H-thymidine autoradiography. Immediately after lumbar puncture, the CSF withdrawn was incubated at 37°C for 1 hr with an admixture of 3H-thymidine at a rate of 1 μCi/ml CSF. The cells were collected by centrifugation and the microautoradiographic procedure was performed. The labeling index (L.I.) of the total CSF cells was 10.5%, and when non-neoplastic cells, i.e. polymorphonuclear leukocytes, small lymphocytes, monocytes etc., were excluded, the real L.I. of the tumor cells in the CSF was supposed to be more than 14.4%. Referring to the results of various brain tumors reported in the literature, this belongs at least to the highest labeling group. The high L. I. of the tumor cells in this case was well consistent with the extremely rapid clinical course. It should be stressed that the examination of CSF cells by 3H-thymidine autoradiography in cases of brain tumors could be one of the valuable methods indicating the DNA synthesis of the tumor cells, which is an important parameter of malignancy.

Human CSF cells in cases of non-neoplastic disease of the central nervous system (CNS) were examined in vitro by 3H-thymidine autoradiography. Immediately after withdrawl by lumbar or ventricular puncture, the CSF was incubated in a sedimentation chamber at 37 degrees C for 1 hr with an admixture of 3H-thymidine at a concentration of 1-2 muCi/ml CSF. In a few cases the CSF withdrawn was incubated in a glass tube in the same condition as in a sedimentation chamber, and the CSF cells were collected by centrifugation. The CSF cells collected were fixed in methanol and the microautoradiographic procedure was performed. Labeled CSF cells were found in 21 cases out of 22. The average labeling index of the total nucleated cells was 0.22% with the highest labeling of 0.74%. Almost all the labeled cells were thought to be medium to large sized lymphocytes and monocytoids. Peripheral blood was examined by a similar method and the results were compared with those of the CSF. It may be noteworthy that thre exist DNA synthesizing cells in the CSF even in a non-neoplastic state of the CNS, although the number is not large.

The authors describe the case of a 19-day-old infant with a ruptured intracranial aneurysm. She had suddenly become lethargic after drinking milk. Cerebral angiography demonstrated a large aneurysm arising from the right middle cerebral artery. Because the aneurysm was fusiform, the parent artery was clipped. Histological examination of a specimen taken from the aneurysmal dome showed an organized thrombus with deposition of a calcium-like substance in the wall, which appeared on histochemical examination to be pseudolime. The postoperative course was uneventful and she was discharged without neurological deficits.

Primary intramedullary spinal glioblastoma multiforme is very rare. Spinal dissemination from intracranial glioblastoma is also uncommon. We present a 13-year-old girl who had difficulty in elevating her right upper extremity and developed spinal symptoms. Metrizamide myelography, computed tomographic metrizamide myelography, and magnetic resonance imaging showed intramedullary mass expanding from medulla oblongata to C-7 vertebral body level. Laminectomy from C-2 to C-7 revealed intramedullary tumor infiltrating the right C-5 spinal nerves. Histopathologically, the surgical specimen showed the peculiar featuers of a glioblastoma multiforme.

✓ A case of cavernous hemangioma of the optic nerve of a 24-year-old pregnant woman is reported. The visual disturbance with subacute onset was thought to be related to the delivery of a child. The lesion was totally removed through the subfrontal approach, resulting in satisfactory recovery of visual symptoms. Cavernous hemangioma involving the optic nerve and chiasm is extremely rare. Only two similar cases have been reported previously.

In order to evaluate subarachnoid dissemination of brain tumor, the cerebrospinal fluid (CSF) cells of 104 patients with brain tumor were examined by 3H-thymidine autoradiography and cytology. As a control CSF cells from 34 patients with non-neoplastic disease were examined by the same method. Immediately after withdrawal by lumbar or ventricular puncture, the CSF was incubated with an admixture of 3H-thymidine at a concentration of 1–2 μCi/ml CSF at 37°C for 1 h. The CSF cells were collected by sedimentation or centrifugation and the microautoradiographic procedure was performed. The labeling index (LI) of CSF cells was counted excluding small lymphocytes and polymorphonuclear leukocytes. Labeled CSF cells were found in 33 of 34 cases of non-neoplastic cases. The mean LI of CSF cells in non-neoplastic cases was 0.4% and the highest was 1.7%. Cytological study revealed neoplastic CSF cells in 15 of 104 cases of brain tumor. A LI exceeding 1.7%, which was the highest in non-neoplastic cases, was encountered in 24 of 104 neoplastic cases. The highest LI in neoplastic cases was 14.4% in a case of primary reticulum cell sarcoma of the brain. High labelings were seen in cases of primary brain sarcoma, metastatic carcinoma, meningeal leukemia and pinealoma. In cases of glioma, even though malignant, the LI was relatively low in most cases. High LIs were parallel with the result of cytology in most cases. It was suggested that either 3H-thymidine autoradiography or cytology of CSF cells alone was not always conclusive for the diagnosis of subarachnoid dissemination of brain tumor, but by using both methods the diagnosis would be obtained with more accuracy.