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Biomedical subjects

K Kyoshima

Publications and source records attributed to K Kyoshima.

At least 73 records · Page 4Linked to original sources
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

Bilateral subdural empyema due to Salmonella enteritidis in an infant.

A case is reported of an infant with bilateral subdural empyema due to Salmonella enteritidis. This Salmonella species is extremely uncommon as a pathogen in a focal infection in the central nervous system. Treatment by early surgical drainage, followed by systemic antibiotics and subdural irrigation, was successful. This is the first case reported of infantile subdural empyema due to S. enteritidis.

Drainage↗
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

Carotid cave aneurysms of the internal carotid artery.

In a series of 32 surgical cases of carotid-ophthalmic artery aneurysm, seven of the lesions were located in the "carotid cave." This special type of aneurysm is usually small and projects medially on the anteroposterior view of the angiogram. At surgery, it is located intradurally at the dural penetration of the internal carotid artery (ICA) on the ventromedial side, appears to be buried in the dural pouch (carotid cave), and is often difficult to find, dissect, and clip. The aneurysm extends into the cavernous sinus space, and the parent ICA penetrates the dural ring obliquely. An ipsilateral pterional approach was used in all 32 cases, and ring clips were used exclusively because the aneurysms were located ventromedially. Clipping was successful in five cases. All patients returned to their preoperative occupation, although vision worsened postoperatively in two cases. The technical steps required for successful obliteration of this aneurysm are summarized as follows: 1) exposure of the cervical ICA; 2) unroofing of the optic canal and removal of the anterior clinoid process; 3) exploration of the ICA around the dural ring and opening of the cavernous sinus; 4) direct retraction of the ICA and optic nerve; and 5) application of multiple ring clips to conform to the natural curvature of the carotid artery; a curved-blade ring clip is especially useful. The relevant topographic anatomy is discussed.

Adult↗
PubMed1988

Microsurgical anatomy of the arteries of the pituitary stalk and gland as viewed from above.

The microsurgical anatomy of the arteries of the pituitary stalk and gland as viewed from above was studied in 50 adult cadaveric hemispheres using the operating microscope. There were three types of vessels to the pituitary from above: the superior hypophyseal artery originating from the internal carotid artery, the infundibular artery from the posterior communicating artery, and the prechiasmal artery from the ophthalmic artery. The superior hypophyseal artery originated from the medial to posterior aspect of the internal carotid artery. The average number of vessels of the superior hypophyseal artery was 2.2 per hemisphere, and the diameter was 0.25 mm on average. The majority (76%) of superior hypophyseal arteries arose from the proximal half of the segment between the origins of the ophthalmic and posterior communicating arteries of the internal carotid artery. The infundibular artery originated mainly from the medial side (69%) of the posterior communicating artery. Its diameter was 0.22 mm, and number 0.23 per hemisphere. The number of prechiasmal arteries was 0.06 per hemisphere. As a result, there were on average 2.5 vessels per hemisphere, totally 5 per brain, with the average diameter 0.25 mm, supplying the pituitary stalk and gland from above. The clinical application of these anatomical data to the diagnosis and treatment of suprasellar tumours and carotid-ophthalmic aneurysms is discussed.

Arteries↗
PubMed1988

[Monostotic fibrous dysplasia of the sphenoidal bone presenting with visual disturbance during pregnancy].

A case of monostotic fibrous dysplasia in the anterior skull base, which presented with visual disturbance during pregnancy, is reported. A 32-year-old female was referred to our department for examination of the progressing right visual disturbance in the third trimester of her second pregnancy. She had experienced the same episode in her first pregnancy, recovering from it after delivery. This time, however, the visual acuity did not change after delivery. Plain craniogram showed sclerotic changes in the right sphenoidal ridge and the right frontal skull base. CT scan showed an isodense mass which was enhanced by contrast medium in the right sphenoidal sinus. Angiography demonstrated no positive findings. RI bone scintigram using 99 m Tc-MDP revealed an abnormal uptake in this region. The patient was operated on in two stages. The first operation was transsphenoidal removal of the tumor in the sphenoidal sinus. The pathological diagnosis was fibrous dysplasia. Transfrontal decompression of the right optic canal and ophthalmic artery was performed at the second operation. The tumor was totally removed and the decompressed orbital roof was reconstructed using an alumina ceramic plate. Visual acuity gradually improved in the follow-up study. To our best knowledge, only one case of fibrous dysplasia with growth during pregnancy have been reported; it was monostotic fibrous dysplasia of the maxilla. From the clinical course of our case, it is suggested that the pregnancy influenced growth of the monostotic fibrous dysplasia; possibly by way of hypothalamic hormonal factor.

Female↗
PubMed1988

[Clinical evaluation of subarachnoid hemorrhage of unknown etiology].

This study concerns 16 cases with spontaneous subarachnoid hemorrhage (SAH) of unknown etiology experienced in our department during a period from September 1979 through August 1986. SAH was confirmed by computed tomographic scanning (CT) or lumbar puncture. All cases were studied by four or three-vessel study. In the case of three-vessel study, adequate opacification of the posterior inferior cerebellar artery contralateral to the injected vertebral artery was considered as a necessary condition. Panangiography was repeated in all patients one to two weeks after the initial study and was negative. The severity of SAH in these patients on admission was relatively mild (Hunt and Kosnik grade I + II = 75%), and the degree of subarachnoid bleeding on CT was also mild. Medium to long-term outcome was excellent or good in 81% of cases, and none of them experienced rebleeding. Only one patient died of severe vasospasm on the 20th hospital day, but no aneurysm was found at autopsy. Illustrative 3 patients in whom the cause of SAH had been finally found was briefly reported. In the first patient, SAH was secondary to a paraventricular cryptic angioma. In the second patient, a microaneurysm had been concealed at the initial angiography by the parent arteries or intra-aneurysmal clot. In the third case of a fusiform aneurysm of the vertebral artery, the aneurysm proximal to the posterior inferior cerebellar artery could not be found at the first three-vessel angiography. Importance of CT and the necessity of repeat panangiography including magnification or oblique views so as not to over-look the causative vascular abnormalities were emphasized.

Adult↗
PubMed1987

Fixation system for cervical spinal operation: application of the head fixation system and multipurpose cervical frame.

We have designed a multipurpose cervical frame to use with our operative head fixation system and have used it in 60 cervical spinal operations including anterior, posterior, lateral, and transoral approaches, with satisfactory results. We emphasize the following advantages of this system: (a) Both stability and an exact position of the cervical spine can be maintained during operation. (b) Positioning of patients for operation, including those with a halo vest, is efficiently carried out with safety and ease. (c) Our newly designed cervical frame enables exact and refined intraoperative retraction with various kinds of retractors. (d) When microsurgery is performed, the surgeon can sit at the patient's head in an operating chair.

Head↗
PubMed1987

[Electron microscopic observation of cells ensheathing axons and their association with basal lamina in sciatic-nerve-grafted spinal cords].

In transected and reanastomosed peripheral nerve, cells proliferate in the scar which unites the proximal and distal cut ends of the nerve. Those cells are considered to produce favorable effects on the advancement of naked axons, and ultrastructural studies have revealed that the naked axons are partially or completely ensheathed by cells in the union scar. On the other hand, in a spinal cord model, structure with a histological appearance similar to that of the union scar in the transected peripheral nerve has been produced experimentally by delayed autogenous sciatic nerve grafting into the transected spinal cord gap. In the present study, the same spinal cord model was used and an electron microscopic study of the junctional area between the spinal cord and grafted nerve was carried out in an attempt to answer the following questions: (1) Do cells in the spinal cord-nerve graft junction ensheath axons? And, if so, (2) is it possible to identify these cells? Five adult dogs were used for the experiment. One week after the first spinal cord transection, the wound was opened, necrotic materials in the gap were carefully removed microsurgically, and segments of autogenous sciatic nerve were placed in the gap of the spinal cord. The dogs were killed at 1 and 3 weeks, 3, 9 and 12 months after the delayed nerve grafting and electron microscopic observations were made. The cells which ensheathed axons at the graft junction were classified into five morphologically identifiable cell types: migratory Schwann cells, committed Schwann cells, astrocytes, oligodendrocytes and macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

[Conjoined lumbosacral nerve roots--diagnosis by metrizamide myelography and metrizamide CT].

Several kinds of the lumbosacral nerve root anomalies have already been recognized, and the conjoined nerve roots is the most common among them. It does not make symptoms by itself, but if there is a causation of neural entrapment, for example, disc herniation, lateral recessus stenosis, spondylolisthesis, etc., so called "biradicular syndrome" should occur. Anomalies of the lumbosacral nerve roots, if not properly recognized, may lead to injury of these nerves during operation of the lumbar spine. Recently, the chance of finding these anomalous roots has been increased more and more with the use of metrizamide myelography and metrizamide CT, because of the improvement of the opacification of nerve roots. We describe the findings of the anomalous roots as revealed by these two methods. They demonstrate two nerve roots running parallel and the asymmetrical wide root sleeve. Under such circumstances, it is important to distinguish the anomalous roots from the normal ventral and dorsal roots.

Adult↗
PubMed1985

Cranioplasty with inner table of bone flap. Technical note.

A new method of cranioplasty is described in which the inner table of the bone flap obtained during craniotomy is used for grafting. The method was used in 10 cases to repair bone defects caused by a growing skull fracture in two, created during removal of an invasive skull tumor in two, during the approach to intraorbital tumors in two, and secondary to craniectomy for additional exposure in four. The method has the advantage that a piece of the inner table for grafting can be obtained from the craniotomy bone flap, without the need for an additional skin incision or taking a graft from another part of the body, and foreign-body reaction is minimal.

Child↗
PubMed1984

Aneurysms of the proximal anterior cerebral artery.

The authors report eight cases of aneurysm of the anterior cerebral artery proximal to the anterior communicating artery (A1 segment). In six of these cases, the aneurysms arose from the proximal anterior cerebral artery at the origin of either a cortical branch (on case), the accessory middle cerebral artery (one case), or a perforating branch (four cases). In another case the aneurysm arose at the proximal end of the fenestration, whereas in the one remaining case no branch was present at the site of the aneurysmal neck.

Aged↗
PubMed1983

Vasoactive intestinal polypeptide immunoreactive and cholinergic nerves in the whole mount preparation of the major cerebral arteries of the rat.

An immunofluorescence histochemical study of vasoactive intestinal polypeptide (VIP) was made in the major rat cerebral arteries of the whole mount preparation. A comparison was made between the distribution of VIP-immunoreactive and cholinergic nerves. An abundant number of VIP-containing nerves were observed in the internal carotid, anterior cerebral, middle cerebral and basilar artery. VIP and cholinergic nerves were unaffected by bilateral superior cervical ganglionectomy. The density and distribution of VIP-immunoreactive fibers was essentially the same as that of the cholinergic fibers of the rat cerebral vasculature. It is suggested that, as was previously demonstrated in other peripheral organs, VIP coexists within cholinergic neurons of the rat cerebral arteries.

Animals↗