[A case of symptomatic interhemispheric arachnoid cyst in the elderly].

The incidence of interhemispheric cyst is rare. There have been only 12 cases reported in adults since the advent of CT. We encountered a case of an interhemispheric arachnoid cyst in a 54-year-old patient who had developed paraparesis. Excision of the cystic wall produced a satisfactory result. The CT and MRI scans were not contributory to histological differentiation of the lesions. According to the literature, however, it is highly likely that these patients are suffering from an arachnoid cyst, when the interhemispheric cyst without agenesis of the corpus callosum occurs in adults.

Dissociation of 99mTc-ECD and 99mTc-HMPAO distributions in herpes simplex encephalitis.

In herpes simplex encephalitis (HSE), the authors noted an evident dissociation between the 99mTc-ethyl cysteinate dimer (ECD) and 99mTc-d,l-hexamethyl-propylene-amine oxime (HMPAO) single photon emission computed tomographies (SPECTs). The patient was a 5-year-old boy with diffuse type of pontine glioma, which was treated with hyperfractionated radiotherapy. Two weeks after the completion of radiation therapy, a lesion suggesting that of HSE was noted in the right fronto-temporal region on magnetic resonance images. 99mTc-HMPAO SPECT showed an increased accumulation of the tracer in this lesion. On the 99mTc-ECD dynamic SPECT, an exaggerated accumulation of the tracer was noted within 80 s of administration, followed by a rapid drop in the accumulation, resulting in a low accumulation in 10 min. It was assumed that this dissociation was due to the different mechanisms to trap HMPAO and ECD in the brain tissue.

Hypervascularity in Lhermitte-Duclos disease--case report.

A 61-year-old male presented with a hypervascular variant of dysplastic gangliocytoma (Lhermitte-Duclos disease) manifesting as gait disorder. Computed tomography and magnetic resonance imaging both showed enhancement of the tumor after injection of contrast medium. Angiography demonstrated a tumor stain. Histological examination showed a double-layered structure comprising an outer layer of myelinated axons and an inner layer of dysplastic granular cells, and numerous dilated thin-walled blood vessels. Partial resection of the tumor resulted in resolution of the neurological deficit.

Dural invasion and proliferative potential of pituitary adenomas.

The relationship between invasiveness and proliferative potential was studied in 31 cases of pituitary adenomas. The invasiveness was determined by histological examination of sellar floor dura resected during transsphenoidal surgery. The proliferative potential of adenoma specimens was examined immunohistochemically using monoclonal antibody (MIB-1). There were 11 adenomas with histologically verified dural invasion out of 31 cases. These adenomas had a higher MIB-1- positive ratio than adenomas without dural invasion (p < 0.05). Pituitary adenomas with a high proliferative potential tend to be invasive.

Cavernous sinus invasion by pituitary adenomas--relationship between magnetic resonance imaging findings and histologically verified dural invasion.

The relationship between magnetic resonance (MR) imaging findings and histologically verified invasion of the cavernous sinus by tumor cells was studied in 26 patients treated surgically for pituitary adenoma. Dural invasion of the sellar floor by tumor cells was found in 10 cases (38%). All patients were classified according to MR imaging findings into three types. Type I showed a gadolinium-enhanced stripe medial to the carotid artery (5 patients), none of which showed dural invasion. Type II showed no enhanced stripe (17 patients), six of which showed dural invasion. Within this type, tumor size and dural invasion showed no correlation. Type III showed displacement or encasement of the carotid artery by the tumor with or without extracranial extension (4 patients), all of which showed massive infiltration of the tumor cells into the dura mater. This study shows that preoperative MR imaging can provide information for assessment of invasion into the cavernous sinus in patients with pituitary adenoma.

[Clinicopathological features of dysembryoplastic neuroepithelial tumor (DNT): four cases report].

We reported four cases of dysembryoplastic neuroepithelial tumor (DNT) with intractable complex partial seizures, and analyzed their clinical and pathological features. The age of patients ranged from four to nineteen years old. Three were boys and one was a girl. The age of seizure onset ranged from eight months to five years. They did not have any neurological deficits. In all cases, CT scan revealed a low density mass in the temporal lobe. Two cases demonstrated calcifications, and another two cysts. The mass demonstrated low signal intensity in T-1 weighted MR images with mild contrast enhancement by Gd-DTPA. Long-term video-EEG monitoring revealed the epileptogenic focus in the temporal lobe on the side of the mass lesion. Anterior temporal lobectomy with total removal of the tumor was carried out in all cases. Hippocampectomy was performed in three cases in which intraoperative electrocorticogram demonstrated spike discharges in the hippocampus. In the surgical specimens, the tumor consisted of increased astrocytes, oligodendrocytes, and some neurons. A cortical nodule appeared in one case, and cortical dysplasia appeared in two cases. It was difficult to distinguish the tumor of case 3 from ganglioglioma because of mild neuronal atypia. The tumor of case 4 demonstrated increased capillary vessels and was also difficult to differentiate from vascular anomalies. The pathological diagnosis of DNT was still difficult. Consequently, we speculated that DNT included some transitional types between congenital anomalies and ganglioglioma.

[Epileptogenicity and neurotoxicity induced by intra-amygdaloid injection of various excitatory amino acids in rats].

The electroencephalographic and histopathological changes following intra-amygdaloid injection of excitatory amino acids were examined in rats. Limbic seizure status was induced after injection of kainic acid (KA), domoic acid (DA), quisqualic acid (QA), alpha-allo-kainic acid (ALLO-KA) and D-glutamic acid (D-GA). The excitatory effect was found to be in the following order: KA > DA >> QA > ALLO-KA >> D-GA. D-GA caused only a transient paroxysmal discharge on EEG. However, seizure was not induced by an injection of L-glutamic acid (L-GA), D-aspartic acid (D-AA) and L-aspartic acid (L-AA). The minimum epileptogenic doses of these amino acids were defined and intra-amygdaloid injection of these doses were performed. Seven days following the injections, histopathological study was performed. These injection resulted in various degree of degeneration and neuronal cell loss of the pyramidal cells in the ipsilateral hippocampus in the following order of severity: DA > or = KA > D-GA > ALLO-KA > QA. These results indicate absence of correlation between epileptogenicity and histopathological changes. Non epileptogenic amino acids induced no pathological changes of hippocampus or the injected site. These results suggest that the severity of hippocampal damage induced by intra-amygdaloid injection of amino acids depends not only on the magnitude of the induced limbic seizure status but also on the difference of neuropharmacological properties of those amino acids in terms of the interaction with their receptors. Further studies are necessary to elucidate the mechanism of actions of these excitatory amino acids in relation to their receptor subtypes.

Pathology of infantile brain tumor.

Five brain tumors in infancy were studied histopathologically. Though four of them could be included in primitive neuroectodermal tumor, histopathological findings were diverse. The diagnoses were medulloblastoma, cerebellar neuroblastoma, pineoblastoma, ependymoblastoma and ependymoma. While conventional stain for microscopy exhibited their specific findings, immunohistochemical and electron microscopical studies revealed morphological findings related functional structures of the tumor cells. These methodology is mandatory in order to elucidate cytogenesis and differentiation of infantile brain tumors.

[A septated syringomyelia with a dramatic clinical course in a young patient with MELAS; a case report].

This is a report of a young girl who showed a recurrence of acute worsening and remission of neurological manifestations, with consistent MRI demonstration of transaxial septated syrinxes in the cervical and the lumbar spinal cord in addition to a tight filum terminale. This 8 year-old girl had developed normally since her birth until August 1989 when she developed a gait disturbance. This worsened acutely on January 1, 1990, with the additional manifestation of a urinary bladder disturbance. General examination failed to show any abnormality or scoliosis. Neurologic examination revealed a monoparesis of the right lower extremity with muscle atrophy and pyramidal tract sign. Fecal constipation and urinary retention were noted. The MRI T1 weighted sagittal image demonstrated an incontinuous low intensity signal in the C1-C7 as well as in the T12-L2 without swelling of the cord. The axial image clearly demonstrated the septations in the syrinx which looked like eye glasses. No definite Gd enhancement was demonstrated. Chiari malformation was not associated, but the tethered cord was well identified. With the administration of steroid, she showed a marked improvement of neurological manifestations. She was able to urinate without difficulty and also walk by herself. For one month thereafter she remained well with minor neurological deficits until she developed a worsening of the gait disturbance with a newly manifested weakness of the left upper extremity. Sensory impairment was also demonstrated below L3. In contrast to the worsening of the clinical symptoms, no definite change in the abnormalities found by MRI was noted.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of primary intracerebral malignant lymphoma in systemic lupus erythematosus].

The patient, a 44-year-old female, was admitted to our department because of right hemiparesis and left oculomotor nerve palsy on February 7, 1986. Neither lymphadenopathy nor hepatosplenomegaly was present. She had been treated with prednisolone for systemic lupus erythematosus (SLE) for one and a half year before admission. The CT scan revealed a homogeneously enhanced mass lesion from the midbrain through the thalamus on the right side. The whole body gallium scintigram showed no abnormal uptake except in the brain. Stereotaxic biopsy was performed. Histopathological diagnosis was malignant lymphoma, diffuse, large cell type (International Working Formulation). The enhanced mass lesion disappeared after radiation therapy. Subsequently, she received chemotherapy. She remained well until May 1988 when she died because of the systemic lymphadenopathy. The association of malignant lymphoma and SLE has appeared occasionally in the literature. Primary intracerebral malignant lymphoma associated with SLE is much rarer but it should be considered in the differential diagnosis of symptoms of the central nervous system in a patient with SLE. Therefore, biopsy of a cerebral mass lesion is mandatory if appropriate therapy such as radiation and chemotherapy is to be administered.

[A case of extracerebral cavernous hemangioma in the middle fossa].

Authors reported an autopsy case of extracerebral cavernous hemangioma in the middle fossa and discussed the effect of irradiation therapy on it. A 72-year-old woman was admitted due to progressive deterioration of consciousness and the right hemiparesis. CT scan revealed a slightly high density mass, which was markedly heterogeneously enhanced with contrast media, in the left middle cranial fossa. Angiogram with prolonged injection demonstrated a faint tumor stain. Craniectomy and partial temporal lobectomy for decompression were performed, but the tumor could not be removed due to uncontrollable hemorrhage. Her level of consciousness further deteriorated, and in addition heart failure developed. And finally she became vegetative in spite of effective irradiation therapy of 46Gy. CT scan taken three months and seven years after the irradiation showed marked regression of the tumor. After the vegetative state for 8 years, the patient died of acute pancreatitis, and autopsy was performed. The cavernous hemangioma with markedly proliferated interstitial connective tissue and thrombosed vessels was verified by microscopical examination. Although the treatment was not successful in this patient, we confirmed that irradiation is useful in the management of the extra-axial cavernous hemangioma in the middle fossa as a pre- or postoperative adjunct therapy.

Lipoma involving the skull. Case report.

The case of an intraosseous lipoma involving the left frontal bone is reported. Lipomas of the bone are rare; only three cases of lipomas involving the skull have previously been reported. The differential diagnosis includes a healing bone infarction or fracture, meningioma, hemangioma, and fibrous dysplasia. Diagnosis prior to surgery is difficult.

Diffuse low-density areas in white matter on CT scans after intracarotid ACNU infusion--report of three cases.

Since 1984, we have treated 11 malignant glioma patients with intracarotid infusion of ACNU [1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)- 3-nitrosourea hydrochloride] in addition to surgical removal and irradiation. We experienced three patients, who showed clinical manifestation of leukoencephalopathy and computed tomographic (CT) findings of diffuse low-density areas in the white matter on the side of ACNU infusion. Two of the three patients showed an additional CT finding of ring enhancement in the temporo-occipital region. The histological diagnosis of the first case was radiation necrosis, while that of the others was recurrent tumor with coagulation necrosis in the surrounding brain. Our experience suggests that intracarotid ACNU infusion increases the hazard of radiation necrosis, and the optimum dose and effective mode of administration should be evaluated.

Intracranial malignant teratoma diagnosed in a fetus--case report.

The authors describe a case of intracranial malignant teratoma in a 28-week fetus, discovered on assessment of the mother's excessive abdominal enlargement. Alpha-fetoprotein levels in amniotic fluid and serum were high. Ultrasonography revealed a large, solid intracranial mass. The fetus was viable until completion of a cesarean delivery, at which time the heart stopped. At autopsy, the fetal brain was found to have been extensively replaced by a solid, cystic tumor, which proved to be a malignant teratoma comprising elements of all three germ cell layers. The authors' experience and review of the reported cases indicate that prenatal malignant intracranial teratoma can be safely and accurately diagnosed, and that immediate delivery or cranial decompression may be advisable when the diagnosis is established. The usefulness and limitations of ultrasonography are particularly emphasized.

Unilateral exophthalmos caused by an invasive pituitary adenoma.

A case of pituitary adenoma associated with unilateral exophthalmos is reported. An intraorbital infiltrative tumor growth was verified by histopathological study. The mechanism of exophthalmos is discussed, and edema of the intraorbital tissue secondary to an inflammatory reaction or venous stasis associated with tumor cell infiltration is considered to be the cause of exophthalmos in this patient.

[Squamous cell carcinoma of the frontal sinus caused osteomyelitis of the frontal bone].

A case of the squamous cell carcinoma of the frontal sinus complicated with osteomyelitis of the frontal bone was reported. A 47-year-old male was admitted to Asahikawa Medical College Hospital because of a bulging of forehead and remittent fever of a six-month history and general convulsive seizures on the day before admission. On physical examination, a bulging of forehead with redness, tenderness and fluctuation was noted. Sense of smell diminished bilaterally. Oto-laryngological examination disclosed paranasal sinusitis. Skull X-P and CT scan suggested osteomyelitis of the frontal bone secondary to frontal sinusitis. However, a frontal sinus tumor with osteomyelitis was also possible. Operation was performed and a granulomatous mass attached to the dura with thick epidural abscess was noted. The mass and affected bone edge were removed. Pathological examination of the specimens disclosed findings of squamous cell carcinoma and osteomyelitis. Recurrence of the tumor rapidly occurred and reoperation was performed a month after the first operation. Postoperative irradiation and chemotherapy with pepleomycin were done but failed to control the growth and recurrence occurred immediately. The tumor penetrated the skin of the forehead and the patient died of cachexy 7 months after the first surgery. Osteomyelitis usually occurred in the metaphysis of long tubular bone and rarely in short bone or flat bone such as a skull. This is attributed to the difference of distribution of the bone marrow vessels. Embolization and subsequent growth of bacteria in the blood flow is less liable to occur in short bone and flat bone.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pituitary oncocytoma].

Since the first reports of pituitary oncocytoma by Kovacs and Horvath, and Landolt and Oswald increasing numbers of cases have been reported with the advent of electron microscopy. It has been posturated that more cases were not precisely diagnosed because of lack of electron microscopic study. We reported two cases of pituitary oncocytoma and discussed clinicopathological aspects. Case 1 A 66-year-old woman had a 6 year history of visual impairment. Neurological examination revealed loss of vision on the left and decreased visual acuity (0.3) with temporal hemianopsia on the right. The endocrinological study revealed moderate panhypopituitarism. Plain skull X-ray, computed tomography and cerebral angiography showed the findings of a pituitary tumor with suprasellar extension. Subfrontal removal of the tumor followed by irradiation was performed. Case 2 A 50-year-old man was well until 8 years previously, when he experienced loss of libido. Three years before entry, the left sided exophthalmos and ptosis were noted. Neurological examination showed a severe visual impairment with a bitemporal field defect, bilateral optic atrophy and disturbance of eye movements on the left. Endocrinological study revealed panhypopituitarism. Radiological studies showed a pituitary tumor with a suprasellar extension and an invasion into the left orbital cavity. Transcranial and then transsphenoidal partial removal of the tumor were done followed by irradiation. Histological examination of the tumors revealed a poorly granurated adenoma with very weak affinity to acid dyes.(ABSTRACT TRUNCATED AT 250 WORDS)

Electroclinical features of kainic acid-induced status epilepticus in freely moving cats. Microinjection into the dorsal hippocampus.

Electrographic and clinical observations were made after the injection of kainic acid into the unilateral hippocampus of freely moving cats. Vehicle solution (phosphate buffer solution) for control study and kainic acid(1, 4 and 12 micrograms) were administered via a chronically implanted cannula. The control group showed no modification during the observation period. After the injection of 1 microgram of kainic acid, focal status epilepticus was observed for 2-3 days and then cats became normal afterwards. In the group of 4 micrograms kainic acid infection, cats demonstrated limbic status for 3 days, and persistent inter-ictal discharges continued during the observation period. Independent amygdaloid seizures and secondary generalized convulsions developed in the cats administered 12 micrograms of kainic acid. The cats died in the status epilepticus. The dose-dependent and substantial effect of KA without the influences of anesthesia and surgery was demonstrated. The results were discussed in relation to the human medial temporal sclerosis and the effects on the emotional mechanism of the limbic system. We suggest this model to be useful in the study of various types of temporal lobe epilepsy and the emotional mechanisms of the limbic system.

Congenital cerebellar neuroepithelial tumor with multiple divergent differentiations.

A case of congenital cerebellar tumor is reported. The tumor is composed of a few incomplete tubular structures analogous to the neural tube, and of neuroblastic, mature ganglionic, astrocytic, ependymal and undetermined neuroepithelial cells. A tentative diagnosis of congenital cerebellar neuroepithelial tumor with multiple divergent differentiations is made: the histogenesis is discussed. From a histogenetic point of view this tumor is given the provisional name of matrix cell tumor.