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Many anomalous phenomena have been observed in NiTi alloys above martensite start temperature, such as softening of the shear constants, increase of internal friction and diffuse scattering of TEM. However, little information has been obtained about the change in the electron system of the parent phase prior to the martensitic transformation, which should be the origin of all pre-martensitic phenomena. In this work, the temperature change of positron annihilation lifetime, which is quite sensitive to electronic-structural changes of matter, were carried out for NiTiCu alloys. The alloys show martensitic transformation from a B2 (cubic) phase to a B19' (monoclinic) phase via a B19 (orthorhombic) phase as the temperature is lowered. We have found anomalous positron lifetime changes in Ni10Ti50Cu40 and Ni15Ti50Cu35 alloys which show a B2–B19–B19' phase transformation. Positron lifetime increases anomalously with decreasing temperature at temperatures higher than the transformation temperature into a B19' phase. On the other hand, positron lifetime does not show any anomaly in the B2 phase of Ni30Ti50Cu20 alloy which shows B2–B19 phase transformation. The positron lifetime of the parent B2 phase shows good agreement with the theoretically-calculated value. Those of the martensite phases of B19 and B19', although, are about 30 ps longer than calculated ones. This big difference between experimental and calculated positron lifetimes cannot be explained by any existing theory.

The authors present the case of a patient with ischemic episodes and recurrent intracerebral hemorrhages probably caused by primary angiitis of the central nervous system (CNS). An initial angiogram revealed multiple cerebral artery aneurysms as well as vascular wall irregularity; a second angiogram obtained 2 years later, however, did not demonstrate the previous aneurysms but instead showed new ones together with stenosis. Based on the histopathological findings and clinical course in this case, the multiple aneurysms appear to have been induced by vascular wall fragility and subsequent self-repair resulting from primary angiitis of the CNS. The authors present the histological and clinical characteristics of this unusual case of granulomatous, necrotizing CNS vasculitis.

Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography.

We present two cases of central giant cell granuloma in the temporal bone. CT showed an enhancing tumor causing a smoothly margined temporal squamosa and floor of the middle fossa. External carotid angiograms showed tumor stain mainly supplied by the temporal branches of the internal maxillary artery. In one case, MR images showed a hypointense mass on both T1- and T2-weighted images that was thought to reflect the pathologic character of this lesion.

Meningiomas are principally benign in nature. Some meningiomas, however, grow fast or recur even after total removal. The biological behavior of meningiomas often can not be predicted from conventional histopathological studies. A monoclonal antibody against proliferating cell nuclear antigen (PCNA) was used to investigate the usefulness of the PCNA index as a parameter to estimate the proliferative activity of meningiomas. Fifty-two meningiomas were examined. The mean PCNA index of recurrent meningiomas (3.37 +/- 0.92%) was significantly higher than that of non-recurrent meningiomas (1.12 +/- 0.51%) (p < 0.005). The PCNA indices of recurrent cases were all higher than 2.0%. A semilog linear regression analysis between tumor doubling time and PCNA index showed a significant correlation (r = 0.90, p < 0.05). An inverse linear correlation between PCNA index and interval to recurrence was observed (r = 0.62, p < 0.05). A good linear correlation was also shown between PCNA index and BUdR labeling index (r = 0.88, p < 0.01). The results of this study suggest that, providing the methods of tissue processing, immunostaining and counting of positive nuclei are unified, the PCNA index is a useful parameter for estimating the biological behavior of meningiomas.

Chordomas are rare neoplasms arising from notochordal remnants found predominantly in the clivus and the sacrococcygeal regions. Most clivus chordomas show extradural extension and bone destruction. Such a tumour can rarely be intradural. This report is concerned with the radiological findings in prepontine intradural chordoma.

A 64-year-old male presented with a unique choroid plexus metastasis from gastric cancer. Computed tomography and magnetic resonance imaging demonstrated a moderately enhanced mass in the lateral ventricle. The tumor was totally removed and histological examination revealed adenocarcinoma. Systemic investigation revealed gastric cancer. The differential diagnosis for intraventricular masses should include the possibility of metastasis from unidentified primary lesions.

Objective: Our goal was to determine the appearance and enhancement pattern of human pineal glands on MRI., Materials and Methods: High-resolution sagittal MR images (3 mm section thickness with an 18 cm field of view) obtained in 60 patients were retrospectively analyzed to determine the size and enhancement patterns of normal pineal glands following the intravenous injection of contrast medium., Results: Pineal glands were either solid (40%) or cystic (60%) with various enhancement patterns: diffuse (15%) and partially enhanced (25%) in solid and ring-like (20%) and peripherally partial (40%) in cystic. Their diameter exceeded 10 mm but was < 20 mm in five cases and resembled cystic pineal neoplasms. Two such cases were found to be histologically normal., Conclusion: Information on the appearance and enhancement patterns of normal pineal glands on MR images can improve the accuracy of diagnosing space-occupying lesions in the pineal region and perhaps help to prevent unnecessary surgery.

Cats are assumed to be one of the most important reservoirs of causative agent of human Q fever especially in urban areas. There is no evidence of Coxiella burnetii infection in cats in Japan prior to this. Sera from 100 cats, collected in various parts of Japan, were examined for antibody against C. burnetii. Sixteen out of the 100 samples contained antibodies against C. burnetii. The prevalence of the antibody decreased from the northeastern to the southwestern part of Japan. A high prevalence of the antibodies was observed in sera from cats of more than four years of age. It is difficult to deny that cats would be one of the important sources of human Q fever in Japan.

We report a case of a 50-year-old woman with traumatic dissection of the right common carotid artery secondary to attempted suicidal hanging. Initial examination showed marks of strangulation on the neck, facial edema, and multiple conjunctival petechiae accompanied by difficulty in breathing and loss of consciousness. She gradually recovered except for her left upper limb weakness. Rehabilitation, with a diagnosis of left brachial plexus injury, was started. Two years later, she occasionally felt numbness of the left upper extremity. On her second admission, a bruit was heard on the right side of her neck. Neurological examination did not reveal any change. CT scan showed atrophic changes. Angiography demonstrated approximately 80% stenosis of the right common carotid artery which was thought to be responsible for the attacks of numbness. Right carotid endarterectomy was performed. Histological findings revealed dissection of the medial layer of the arterial wall. Complaints of numbness disappeared postoperatively, and angiography showed good patency at a follow-up examination. We conclude that the stenosis of the common carotid artery was not due to atherosclerosis but due to the dissection as a result of hanging.

An unusual case of a giant prolactinoma extending to the nasopharynx and nasal cavity is presented. A 35-year-old man admitted for nasal obstruction and visual disturbances was found to have bilateral anosmia, right homonymous hemianopsia, and a right hemiparesis. The serum prolactin level was 13,300 ng/mL. Radiological examination revealed a large mass invading the skull base and extending into the suprasellar region and the left frontal lobe superiorly and into the nasopharynx inferiorly. Subtotal removal was done through a bilateral orbitofrontal craniotomy, which was followed by radiotherapy and bromocriptine administration. Immunohistochemical analysis confirmed a prolactinoma. The rarity of such a tumor, its location and extension, and the usefulness of magnetic resonance imaging and immunohistochemistry are stressed. Pertinent literature is reviewed.

Magnetic resonance (MR) images obtained in 35 patients with intramedullary spinal tumors were reviewed. Hypointense areas on both T1- and T2-weighted images were seen within or around eight tumors, all of which were in the cervical cord. Hypointensity at the tumor margin was seen in seven cases. Hypointensity within the tumor was seen in two cases. (One case had both types of hypointensity). In seven surgically confirmed cases, hypointensity at the tumor margin was found to be a relatively firm pseudocapsule, and hypointensity within the tumor corresponded to intratumoral hematoma. All of the tumors with hypointensity were ependymomas at histologic examination. When MR imaging shows an intramedullary tumor with hypointensity at the tumor margin, it is suggestive, but not pathognomonic, of an ependymoma.

We treated three cases of inflammatory granulomas extending from the sphenoid sinus to the cavernous sinus. Case 1 was that of a 36-year-old male with diplopia and right ptosis. Case 2 was that of a 40-year-old male with frontal headache. Case 3 was that of a 70-year-old female with left impaired vision and frontal headache. In the first case, MRI demonstrated a mass lesion extending from the right half of the sphenoid sinus to the cavernous sinus and retropharyngeal space. In the second case the granuloma extended from the right cavernous sinus to the right retroorbital space. In the last case, MRI demonstrated diffuse Gd-DTPA enhancement of the left cavernous sinus and the left half of the sphenoid sinus. In all cases an operation was performed using the sublabial rhinoseptal approach, and the tumor in the sphenoid sinus was removed. Histological examination revealed an inflammatory granuloma in all 3 cases. In the first case the clinical symptoms improved following administration of glucocorticoids. In the second case the mass in the cavernous sinus decreased in size postoperatively. In the last case, the clinical symptoms gradually improved with administration of antibiotics after surgery. Granuloma of the cavernous sinus is difficult to diagnose, but when a similar pathological lesion coexists in the sphenoid sinus, a definitive diagnosis can be easily made via the sublabial rhinoseptal approach.

Ectopic pituitary adenomas are very rare and only 17 cases have been reported. In this paper we present a case of large pituitary adenoma originating in the suprasellar region. A 26-year-old man was admitted to our clinic with a chief complaint of headaches. Neurological examination revealed slight disorientation and bilateral choked disk. Hormonal study revealed that the serum prolactin level was 3300ng/ml and serum growth hormone level was 29.5ng/ml. Computed tomography showed a large mass in the suprasellar region extending upward to the third ventricle and backward to the pons. T1-weighted MR imaging revealed that the intensity of the mass was the same as that of the cerebral cortex and the pituitary gland was showing high intensity in the pituitary fossa. The tumor was radically removed via the transpetrosal transtentorial approach. Histologically, the tumor was a prolactin-growth hormones producing pituitary adenoma. The literature was reviewed and the origin of the tumor was discussed.

The fine structural features and water content of white matter associated with the resolution process of brain edema were sequentially investigated in the model produced by infusion of autoserum, mock CSF, or ferritin into the centrum semiovale of cats. The correlation between water content and morphological features was good. Mock CSF-infused edema disappeared within 3 days, serum infused edema within 6 days. In a fine structural study of serum-infused white matter, the distended extracellular spaces were found to be occupied with electron-dense materials, active phagocytosis of the dense materials being observed in the macrophages. Around the postcapillary venules, edematous changes were characterized by wide expansion of the perivascular spaces between endothelial cells and astrocytic endfeet. In some instances, the dense materials in the cytoplasm or in the membrane-bound vacuoles of the astrocytic endfeet were continuous with those in the perivascular space, through the hiatuses of the perivascular astrocytic endfeet being separated at their margins. At 3 days after infusion, wide distension of the extracellular space persisted, but the dense materials had markedly diminished. These results strongly suggest that water clearance of vasogenic brain edema does not commence until proteinaceous macromolecules are degraded and removed from the extracellular space. Perivascular channels around the postcapillary venules might also have some role on the movement of edematous fluid.

Epithelial cell cultures of urothelial origin can be initiated with the sediment of voided urines of normal adults. The proliferating cells can be subcultured provided that nonconfluent cultures are used. In some instances cells have been transferred up to seven times. Flow cytometric analysis of the cells grown in vitro revealed a DNA distribution pattern consistent with a nonsynchronized, proliferating diploid cell population. Karyologic studies showed that 98% of the cells were diploid and had normal banding patterns. Tetraploid cells with 92 chromosomes constituted about 2% of the counted metaphases. These observations, supplementing the authors' previous data provide further evidence that urothelial cells derived from normal adults retain characteristics of normal human cells. Urine represents an easily available source for initiating cultures of human epithelial cells and the application of the system in diagnosis and research is being explored.

Cytogenetic analyses of eight meningiomas grown in culture for 1 week are reported. Normal karyotypes were found in three cases and hypodiploidy in the remaining five. In the five hypodiploid meningiomas, one chromosome #22 was missing in four cases, and one case exhibited a 22q- deletion. In four of these five cases, chromosome #14 was either lost or altered. Chromosome #1 was lost or altered in three, and chromosome #6 in two. These findings lend further support for the association of total or partial loss of chromosome #22 in meningiomas and suggest the involvement of other chromosomes in the clonal evolution of these tumors.

Although meningiomas have been regarded as one of the benign brain tumors, cases showing clinically malignant behavior have been reported. For the purpose of detecting the possibility of predicting different biological behavior in meningiomas, eleven meningiomas were studied with the aid of flow cytometric (FMC) and cytogenetic techniques. Morphologically two cases were diagnosed as syncytial meningiomas and nine as transitional meningiomas. The former included one case (#5) of "syncytial poorly structured meningioma" (Zang et al.). In the FCM study seven out of eleven cases showed diploid (2C) or near diploid modal peaks with small amounts of tetraploid DNA (4C) cells. The remaining four cases had larger cell populations at 4C. Cytogenetically cells corresponding to 2C and near 2C peaks were also proved to be composed of diploid or hypodiploid cells in all of the eight cases studied. Chromosomal analyses revealed normal karyotypes in three. The remaining five hypodiploid cases had common chromosomal aberrations in G22, including missing chromosome 22 in four cases and 22 q-deletion in one. Nine cases grown in culture were also studied by FCM and were able to be maintained in culture from 14 days to 5 months. Close to the terminal stage of culture, most of the cases in culture tended to have higher cell population at 4C and the appearance of cells even at 8C (polyploidization). Similar changes were also obtained in cultured human fibroblast and seem not to be specific to this benign tumor. These results are discussed with reference to the previous reports from the point of view of patterns of FCM histograms from surgical specimens, degree of hypodiploidy, morphological behavior. Further studies, especially relating to basic cell kinetics are needed before clinical application can be made.

Although infiltrating angiolipomas are histologically benign, recurrence has been reported in more than 50% of patients after partial extirpation. The authors have treated a 14-year-old female with a large infiltrating angiolipoma of the neck, in whom magnetic resonance imaging was more valuable than x-ray computed tomography and angiography in delineating the extent of the tumor. Total removal of the tumor was performed with the aid of an operating microscope. To our knowledge, this is the first description of the magnetic resonance imaging of an infiltrating angiolipoma. When other neuroradiologic examinations cannot be considered to demonstrate the extent of the tumor accurately, magnetic resonance imaging may be recommended.

This experimental work was carried out to examine whether activation of autonomic cortical and hypothalamic areas by electrical stimulation is related to changes in the intracranial pressure (ICP) in cats anaesthetized lightly with sodium pentobarbital. Electrical stimulation was performed using a concentric electrode with a train of electrical pulses (pulse duration, 0.4 ms; frequency, 40 Hz; intensity, 50-400 microA). Stimulation of sites in the anterior cingulate gyrus produced a rise in ICP associated with a fall in systemic arterial blood pressure (BP) or with no change in BP. Stimulation of sites in the anterior hypothalamus produced a fall in BP with an increase in ICP. Stimulation of sites in the area extending from the anterior hypothalamus to the posterior hypothalamus produced rises in BP and ICP. These observations suggest that activation of autonomic cortical and hypothalamic areas is involved in changes in ICP.

It has been suggested that brain stem activity is involved in the occurrence of pressure waves. Different sites in the brain stem were activated by electrical stimulation in cats anaesthetized with sodium pentobarbital, to produce an increase in intracranial pressure (ICP) similar to the pressure waves. Then the effect of artificial ventilation on the occurrence of the pressure wave-like response produced under spontaneous respiration was examined since Lundberg's A-waves appear even in artificial ventilation, and B-waves are effaced during artificial ventilation. This results in a brain stem map of ICP and systemic arterial blood pressure (BP) produced by electrical stimulation during spontaneous respiration. Stimulation of the rostral medullary reticular formation produced a rise in ICP and BP in association with a change in the rhythm of the spontaneous respiration; with artificial ventilation, stimulation produced a rise in BP but ICP kept almost at the same level. However, the rise in ICP that was produced by stimulation of the caudal medullary reticular formation during spontaneous respiration also occurred with a depressor response of BP during controlled ventilation. The pressure wave-like responses could be classified, therefore, into two types. One was the response seen during both spontaneous and controlled ventilation, which we designated the 'alpha' wave. The other was the response seen only during spontaneous ventilation, the 'beta' wave. These observations suggest that the origins of A- and B-waves may be related to those of 'alpha' and 'beta' waves, respectively.

The management of patients with intramedullary spinal cord tumours is controversial. The authors have treated these tumours in accordance with the principles of radical resection, using microsurgical techniques. There have been 22 cases of intramedullary spinal cord tumours (4 astrocytomas, 3 glioblastoma multiformes, 5 ependymomas, 7 haemangioblastomas, 1 dermoid, 1 lipoma and 1 schwannoma) thus treated at our department during the past 13 years. Sixteen were adults and six were children. The early and late results of their surgical treatment have been analyzed, with follow-up periods ranging from 10 months to 12 years. Of the 22 patients, total removal was performed in 16, subtotal removal in 5 and biopsy in 1. Guidetti's criteria were adopted in assessing the results of surgery. Long-term results were as follows: 8 very good, 5 good, 3 fair, 3 poor and 3 deceased. The 3 latter cases were glioblastoma multiformes. Gross total removal of intramedullary tumours is technically feasible and compatible with neurological recovery. Since the majority of intramedullary tumours are benign and their course may span not only years but decades, long-term follow-up is essential.

Two of three patients who proved to have symptomatic Rathke's cleft cysts presented with visual field deficit and all with diabetes insipidus. CT showed intra- and suprasellar cystic low density lesions with ring enhancement. MR showed intra- and suprasellar masses. On the T1-weighted images two of the three had hyperintense portions similar to fat and the other a hyperintense portion similar to white matter within the cysts. These portions were isointense to brain on the T2-weighted images in all cases. This characteristic intensity on MR images provides differentiation from cystic pituitary adenomas and cystic craniopharyngiomas, and leads to correct diagnosis of Rathke's cleft cyst.