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Biomedical subjects

J Handa

Publications and source records attributed to J Handa.

At least 109 records · Page 6Linked to original sources
PubMed1990

Cerebral hemodynamics in patients with normal pressure hydrocephalus: correlation between cerebral circulation time and dementia.

Regional cerebral blood flow and regional cerebral circulation time were measured in 13 demented patients with chronic hydrocephalus, mostly normal pressure hydrocephalus. The average hemispheric, frontal, and temporal cerebral blood flows were significantly reduced. The average regional cerebral circulation time values were significantly prolonged in the frontal, temporal, and thalamic regions, most markedly in the frontal white matter, where periventricular lucency was observed on computed tomography. Clinical improvement was obtained in all patients after operation. While postoperative regional cerebral blood flow values did not change compared with preoperative ones, postoperative regional cerebral circulation time values were significantly reduced in all the regions measured, and most markedly in the frontal white matter. The present results suggest that microcirculation in the frontal lobe is closely correlated with dementia in association with pressure exerted on the nerve fibers in the frontal white matter in patients with normal pressure hydrocephalus.

Aged↗
PubMed1990

Magnetic resonance imaging of large and giant intracranial aneurysms.

Twelve large or giant intracranial aneurysms were studied with magnetic resonance (MR) imaging, and the findings were compared with those from computed tomographic (CT) scanning. Characteristic MR features of such aneurysms are: round, extra-axial mass with hypointensity rim; signal void, paradoxical enhancement, or even-echo rephasing due to blood flow; and laminated, eccentric thrombus with increased signal intensity when fresh, perianeurysmal hemorrhage occurs in the acute or subacute stage after aneurysmal rupture. MR imaging, however, often fails to identify or characterize the area of calcification. For the diagnosis of large or giant intracranial aneurysms, MR imaging is apparently superior to CT scanning in differentiating aneurysms from tumors, delineating the blood flow and intraluminal thrombus, and detecting the exact size of the aneurysm. It may also provide useful information concerning the growth mechanisms of aneurysms with or without thrombus formation.

Adult↗
PubMed1989

[Use of fibrin glue (Beriplast P) in neurosurgical practice].

1. Beriplast P was used in 48 places, at 36 neurosurgical operations in 34 patients for various purposes. 2. No complications were encountered. Its use proved useful for sealing an inadvertently entered paranasal sinuses and as an auxiliary measure of controlling venous bleeding from dural sinuses or dural venous lakes difficult to control by usual means. 3. As to its use for sealing the site of dural closure to prevent the leakage and accumulation of the cerebrospinal fluid, it proved useful in the selected patients, but it should be emphasized that the meticulous closure with surgical sutures is of utmost importance and that the availability of fibrin glue does never replace the skillful operative techniques. 4. A case where Beriplast P applied over the dural surface caused obstruction of an epidural drain and resultant epidural hematoma was presented.

Female↗
PubMed1989

[Angiographically occult vascular malformations in the posterior fossa].

Three cases of spontaneous intraparenchymal hemorrhage in the posterior fossa were operated upon, and the diagnosis of thrombosed vascular malformation was histologically confirmed in two of them. So-called "angiographically occult" vascular malformations often present characteristic magnetic resonance (MR) images, namely, iso- to high intensity signal core surrounded by a low intensity signal rim or area on both T1 and T2 weighted images. Such findings are thought to indicate that subacute and chronic intraparenchymal hematoma has a relatively short T1 and long T2 relaxation times, resulting in an area of relatively increased signal intensity, and that hemosiderin deposits apparently decrease T2 relaxation time by paramagnetic effect. Most such lesions do not show significant perifocal edema. Occasionally, however, perifocal edema may be seen as in our Case 3, and the differential diagnosis from the tumor, particularly bleeding tumor, may become difficult even with the recent technical standards of high resolution CT and MRI. Reasons responsible for non-visualization of such vascular malformations at angiography are discussed. Small size of the lesion, slow blood flow through it, compression by adjacent clot or gliotic scar, spontaneous or secondary thrombosis with hyalin degeneration, and destruction at its rupture are possible factors.

Adult↗
PubMed1989

[MRI of brainstem contusion].

Three cases of brainstem contusion in whom the lesion could not be found by x-ray computed tomography (CT) but was identified clearly by magnetic resonance imaging (MRI) were reported. CT is apparently very useful in detecting the hemorrhagic components in patients with acute head injury, and it will definitely retain its important role in the management of emergency patients with possible life-threatening intracranial hemorrhage. MRI has been also known to be very useful in the diagnosis of patients with head injuries, especially in the detection of contusion in the frontal base, tip and the base of the temporal lobe, and the brainstem. T2-weighted images are the best for demonstrating such traumatic contusion of the brain.

Adolescent↗
PubMed1989

Morphogenesis of the secondary palate in mouse embryos with special reference to the development of rugae.

Morphological studies of secondary palate formation, with special reference to the development of rugae, were carried out on Jcl:ICR mouse embryos. Three rugae were observed on the anterior part of the future oral surface of the vertically developing palatal shelves in 13-day embryos. Rugae increased in number as the development of the palatal shelves proceeded, and five to six prominent rugae were observed in 14-day embryos just prior to shelf elevation. The folding of these five to six rugae progressed in conjunction with the formation of a sharp, valley-like groove at the base of the anterior two-fifths of the vertical palatal shelves. As palatal shelves elevated, the groove disappeared gradually, and, accordingly, the folding of rugae loosened. In the groove region, the superficial epithelial cells were roundish, while the basal ones were elongated. Such characteristic features were no longer observed when the disappearance of the groove was completed. Eight rugae were observed on the future hard palate of 14-day embryos with already completed palatal fusion. An additional ruga was frequently found in 15-day embryos, and the pattern then was almost the same as that of an adult. Epithelial thickening and condensation at the rugae region, as well as mesenchymal condensation under the epithelium of the rugae, were confirmed in embryos both before and after elevation of the palatal shelves. There is a possibility that these structural characteristics observed in the epithelial and mesenchymal cells of the rugae and groove regions may be related to palatal shelf elevation.

Animals↗
PubMed1989

Effects of a novel calcium antagonist, KB-2796, on neurologic outcome and size of experimental cerebral infarction in rats.

Effects of a novel calcium 2+ antagonist, KB-2796, on neurologic outcome and size of infarction were studied in the rat model of focal cerebral ischemia. Neurologic deficits were examined from 1 to 24 hours after occlusion of the middle cerebral artery and size of infarction was measured at 24 hours postocclusion. When KB-2796 (10 mg/kg, IP) was given immediately after, or 1 hour after, middle cerebral artery occlusion, marked improvement in neurologic score was seen 1 to 3 hours postocclusion. When given immediately after middle cerebral artery occlusion, size of infarction was also markedly smaller when compared with the control rat. The present study suggests that the calcium 2+ antagonist KB-2796 has brain-protective effects against ischemia even with its administration after induction of ischemia.

Animals↗
PubMed1989

Huge meningioma in a child.

A case of a 6-year-old boy with a large meningioma is reported. The patient had an enlarged head, the Foster Kennedy syndrome, and roentgenological evidence of increased intracranial pressure. A computed tomography scan and magnetic resonance image showed a huge tumor in the right parietooccipital region. The tumor was totally resected with the involved right transverse sinus in staged operations. Histology was transitional meningioma. The incidence of intracranial meningiomas is low in childhood. The literature is reviewed, and some peculiarities of childhood meningiomas are discussed.

Age Factors↗
PubMed1989

Intracranial glossopharyngeal neurinomas. Report of two cases with special emphasis on computed tomography and magnetic resonance imaging findings.

Two patients with intracranial glossopharyngeal neurinoma are described. In both patients, neurologic signs and findings of conventional radiologic and computed tomography examinations suggested a diagnosis of acoustic neurinoma. Magnetic resonance imaging, however, definitely indicated that the mass had actually arisen from the lower cranial nerves. This was confirmed at operation. The superb sensitivity and specificity of magnetic resonance imaging in the diagnosis of posterior fossa extraaxial mass are emphasized.

Cranial Nerve Neoplasms↗
PubMed1989

Focal brain ischemia model in rats. An experimental study.

Using 74 male rats, anatomical variations of branching of the proximal segment of the middle cerebral artery were studied. In 36 rats (28 Sprague-Dawley rats and eight spontaneously hypertensive rats), the middle cerebral artery and/or its branches were occluded at various sites. Occlusion of the middle cerebral artery at the lateral border of the olfactory tract with or without simultaneous ligation of the ipsilateral common carotid artery rarely caused cerebral infarction in Sprague-Dawley rats. Occlusion of the olfactory branch in addition to the trunk of the middle cerebral artery caused large infarction of the pallium in five of eight Sprague-Dawley rats. Occlusion of the middle cerebral artery at the medial border of the olfactory tract caused infarction in the pallium and/or basal ganglia in five of six rats, and neurologic deficits were severe and persistent. Occlusion of the middle cerebral artery at the lateral border of the olfactory tract in spontaneously hypertensive rats caused large infarction with severe neurologic deficits in all eight animals. Possible factors responsible for such diverse differences and the relative value of each group as an experimental model of focal cerebral ischemia in rats were discussed.

Animals↗
PubMed1989

Interface between the meningioma and the brain.

Though meningiomas are usually well demarcated from the brain, their interfaces with the brain take various forms. Based on 27 nonoperated supratentorial meningiomas from autopsies, the interfaces were classified into four types, that is, smooth, lobular, finger-like expansion, and invasive. Relationships between the types of interfaces and the so-called capsule of the tumor and subarachnoid vessels are discussed. Additionally, three surgical cases which showed more or less the invasive form are presented with neuroradiological findings.

Adult↗
PubMed1989

Pituitary adenoma with multiple ciliated cysts: transitional cell tumor?

The case of a prolactin-secreting pituitary tumor with multiple cyst formation is described. Ultrastructurally, the cyst-lining cells were ciliated and closely resembled those of Rathke's cleft cyst but contained secretory granules, and no basal lamina formation was seen between the adenoma cells and the lining cells. Immunohistochemical study revealed that the adenoma cells consisted of both prolactin-secreting cells and growth hormone-secreting cells. The lining cells were immunoreactive with the antiserum to cytokeratin. No S-100 protein-positive cells were seen. The origin of this tumor is discussed.

Adult↗
PubMed1989

[Comparison of computed tomographic scanning and magnetic resonance imaging in the diagnosis of trigeminal schwannoma. Report of four cases].

Four cases of trigeminal schwannoma with different clinical presentations are reported. Two patients had root-type tumors and two ganglion-type tumors. Computed tomography demonstrated the mass in each case, but extension of the tumor into Meckel's cave, displaced but uninvolved seventh and eighth cranial nerves, extension of the tumor into the orbit or into the infratemporal fossa, and other anatomical details were far more clearly shown by magnetic resonance imaging, which provided confirmation of the mass lesions in the base of the brain and within the posterior fossa.

Adult↗
PubMed1989

Primary intracranial epidermoid carcinoma--case report.

A 38-year-old male who presented with trigeminal nerve paresis was found to have a cerebellopontine angle tumor. The tumor was subtotally removed. Multiple histological sections showed no malignant changes, and the diagnosis was typical epidermoid cyst. Tumor growth recurred twice and the diagnosis after the third operation was epidermoid carcinoma. A review of the available literature yielded only 22 reported cases of malignant intracranial epidermoid cyst.

Adult↗
PubMed1989

Intratemporal facial nerve neurinoma--case report.

A 59-year-old female had episodes of vertigo for 13 years, right tinnitus for 6 years, and right hearing difficulty for 2 years. She had no facial nerve dysfunction or other neurological deficits. Postcontrast computed tomography (CT) did not show abnormalities, but a wide, high-window CT scan revealed erosion of the petrous pyramid on the right side. Magnetic resonance imaging clearly delineated the entirety of a small tumor transecting the petrous bone. At operation a neurinoma was found to originate from the facial nerve proximal to the geniculate ganglion; it was totally removed. This case is unique in that she had a long history of signs and symptoms of acoustic nerve disturbance, but no facial nerve dysfunction whatsoever.

Cranial Nerve Neoplasms↗
PubMed1989

[Olfactory neuroblastoma with intracranial extension. Report of two cases].

Two cases of olfactory neuroblastoma with intracranial extension are described. The radiological features, including those of magnetic resonance (MR) imaging, are emphasized. On plain X-rays, the nasal cavity, ethmoid, sphenoid, and/or frontal sinuses were opacified. Erosion of the bony confines of the sinuses and orbit was seen in Case 1, but no bony destruction was observed in Case 2 despite intracranial tumor invasion via the seemingly intact cribriform plate. Angiography showed tumor staining in the ethmoid sinus, and in Case 1 tumor vessels were also found in the base of the frontal lobe. Computed tomography (CT) disclosed a large, soft, enhanced tissue mass occupying the nasal cavity and paranasal sinuses and extending into the anterior cranial fossa. In Case 1, MR images (0.5 Tesla) with a short spin echo sequence (repetition time [TR], 600 msec; echo time [TE], 26 msec) and a long spin echo sequence (TR, 2100; TE, 30, 60, 90) were obtained. T1-weighted images delineated the tumor accurately in relation to the normal architecture. T2-weighted images revealed widespread brain edema, with the tumor recognizable as a mass of low signal intensity within the high-intensity region of brain edema. The CT and MR imaging findings are by no means specific to olfactory neuroblastoma. However, both modalities, particularly MR imaging, are of special value in demonstrating the precise extent of the tumor in three dimensions.

Humans↗