Biomedical subjects

S Ban

Publications and source records attributed to S Ban.

At least 19 recordsLinked to original sources

PubMed1995

Effect of radiation and cigarette smoking on expression of FUdR-inducible common fragile sites in human peripheral lymphocytes.

In vitro X-irradiation of human peripheral blood lymphocytes increased the frequencies of fluorodeoxyuridine-induced fragile sites in a dose-related manner. However, the cells from 30 atomic bomb survivors exposed to either high or low radiation doses 47 years earlier showed no demonstrable difference in fragile site expression, indicating that fragile site induction was ephemeral in nature. When fragile sites were analyzed on the basis of tobacco smoking habits, an elevated number was observed in the smokers. The results confirm that fragile sites can be affected by recent exposure to exogenous agents, but the effect is probably of limited duration, based on the atomic bomb survivor experience.

Aged↗

PubMed1995

Absorbed dose measurements and calculations in phantoms for 1.5 to 50 keV photons.

A Monte Carlo code EGS4 expanded for low energy photon transport was validated by measuring absorbed doses in a phantom for 30 and 10 keV monoenergetic photons from synchrotron radiation. Using the EGS4 code, depth doses at 0.07 mm, 0.02 to 0.1 mm, and 10 mm in the ICRU slab phantoms were calculated for 1.5 to 50 keV photons using the updated photon cross section data PHOTX. The results show that the doses at 0.02 to 0.1 mm below 10 keV are practical indices of effective dose as calculated by others, based on the 1990 ICRP recommendations (1991).

Humans↗

PubMed1995

[Primary oculomotor nerve palsy due to head injury: analysis of 10 cases].

Ten cases of primary oculomotor nerve palsy due to head injury are presented. All ten patients had a dilated, non reactive pupil. Seven had complete oculomotor palsy. Two had partial extraocular palsy or blepharoptosis and one had neither extraocular palsy nor blepharoptosis. The initial ophthalmoplegia was recognized immediately after trauma. Nine patients had severely impaired consciousness on admission, but eight patients recovered fully within two months after the traumatic event, while one patient remained disoriented. Emergency CT scan on admission showed mass lesions in no patients except one who had a hematoma measuring 3 cm in the frontal lobe, but had no herniation sign. Patients with complete oculomotor palsy had a high incidence of traumatic SAH (71%) or skull fracture (57%). Recovery from third nerve palsy was not so good. The follow-up period extended from 3 months to 18 months. Of the 10 patients, none recovered completely from third nerve palsy. The prognoses of blepharoptosis, external ophthalmoplegia and internal ophthalmoplegia were analyzed separately. The recovery rates were 78%, 44% and 20%, respectively, the internal ophthalmoplegia showing poorest recovery. We discuss the mechanism of direct injury to the oculomotor nerve.

Adult↗

PubMed1995

[Leiomyosarcoma metastatizing to the sphenoid bone presenting exophthalmos: a case report].

A rare subcutaneous leiomyosarcoma metastatizing to the sphenoid bone and presenting exophthalmos is reported. A 56-year-old female presented with protrusion of the right eye and a slowly growing lump on the right temporal region. Six years previously, she had undergone removal of a subcutaneous mass in the back, which was histologically diagnosed in another hospital as leiomyosarcoma. She had undergone four other operations, including removal of local recurrences and a right renal metastasis. On admission, physical examination showed no neurological deficits. Craniogram revealed an osteolytic lesion without marginal sclerosis in the right sphenoid bone. CT showed an inhomogeneously enhanced mass with irregular expansion of the diploic space, which was partly invading the right orbit. MRI demonstrated an extradural mass in the right sphenoid region, which was slightly low-intense in T1-weighted image, high-intense in T2-weighted image, and inhomogeneously enhanced by Gd-DTPA. Right external carotid angiogram showed a highly vascular stain fed by meningeal arteries. Radionuclide bone scintigram showed multiple high-uptake areas in the left femoral head, the ribs, and the sphenoid bone. Preoperative embolization of the tumor vessels fed by the external carotid artery was performed. Following this procedure, the tumor stain disappeared completely. The tumor was totally excised with minimal bleeding through an orbitozygomatic approach. The tumor was loosely adherent to the dura and periorbit. The bone defect was covered with a methylmethacrylate resin plate. the histological examination demonstrated fascicular arrangement of the spindle shaped cells with mitotic figures. Immunohistochemical studies showed that most tumor cells were positive for actin and myosin, but negative for desmin.(ABSTRACT TRUNCATED AT 250 WORDS)

Exophthalmos↗

PubMed1995

[Non-traumatic cerebrospinal fluid rhinorrhea associated with hydrocephalus: a case report].

We report an unusual case of non-traumatic cerebrospinal fluid rhinorrhea associated with aqueductal stenosis and hydrocephalus. The patient was a 10-year-old girl who suddenly developed massive CSF rhinorrhea following severe edema of the left side of her face. CT scan showed marked dilatation of the lateral and third ventricles and enlarged sphenoid sinus of water density, extending to the lateral wall of the left orbit and to the left pterygoid fossa. Immediately after the onset of CSF rhinorrhea, ventricular drainage was performed, but the rhinorrhea persisted. Ventriculography revealed predominant flow of the contrast medium into the left temporal horn and abnormal collection in the sphenoid sinus. Coronal CT scan did not show any focal bony defect, but a thin layer was seen in the base of the left middle fossa. Exploration of the skull base in the left middle fossa was performed through a left frontotemporal craniotomy. An irregular bony defect measuring 7 x 12mm was then found in the anterolateral floor of the middle fossa and the dura was also perforated there. Brain tissue including the temporal horn protruded through the bony defect into the sphenoid sinus. After excision of the herniated brain tissue, repair was accomplished by packing muscle into the bony defect and covering the dural defect with fat reinforced by coating with fibrin glue. Postoperatively, the CSF rhinorrhea has stopped and the edema of her face has disappeared. We discuss the etiology of this unusual spontaneous CSF leakage through the middle fossa and the abnormally enlarged sphenoid sinus.

Cerebrospinal Fluid Rhinorrhea↗

PubMed1995

[A case of deep sylvian meningioma presenting temporal lobe epilepsy].

A rare case of deep sylvian meningioma is presented. A 62-year-old woman was admitted to our hospital because of one year history of temporal lobe epilepsy. She had no neurological deficit except for EEG abnormality. CT scans showed a small calcified mass in the left temporal lobe adjacent to the sylvian fissure with no enhancement by contrast medium. The mass was low-intense in both T1- and T2-weighted MR images. The T1-weighted image after the infusion of gadolinium revealed enhancement of the middle cerebral artery adjacent to the mass, similar to dural tail sign. Left external carotid angiography did not show any tumor stain nor the dilatation of the middle meningeal artery. Left internal carotid angiography disclosed enlarged middle cerebral artery without tumor stain. A left frontotemporal craniotomy was performed and the mass was totally removed. The tumor was located deep in sylvian fissure without any connection to the dura or ventricular system, which was firmly adherent to the middle cerebral artery. The histological examination of the surgical specimen revealed a psammomatous meningioma. Meningiomas are believed to originate from the arachnoid cap cells and can arise from various intracranial locations where arachnoid cap cells exist. The majority of them are attached to the dura, choroid plexus, or the tela choroidea. Only eleven cases of deep sylvian meningiomas have been presented in the literature. We have reviewed the clinical and radiological findings in such meningiomas. MR findings in deep sylvian meningioma have not been described.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Aqueduct↗

PubMed1994

Calcium phosphate precipitation on the surface of HA-G-Ti composite under physiologic conditions.

Hydroxyapatite-glass-titanium (HA-G-Ti) functionally gradient composite plates bound face-to-face by nylon wire were soaked in a simulated body fluid. The gap between the plates was filled with the precipitates after soaking for 6 months, and a tight chemical bond was formed between them. Field emission-type (FE) scanning electron microscopy (SEM) and transmission electron microscopy observations revealed that the growth rate and morphology of the precipitates differed widely from the outside portion to the inside one on the surface region of the composite plates. In the portion relatively near the outside, the mutually bonded portion, needle-like precipitates with preferred orientation to the c-axis were markedly observed. From the results of Fourier transform infrared spectroscopy and energy dispersive x-ray microanalysis, it was found that the precipitates were Ca-deficient carbonate apatite with low crystallinity. On the other hand, HA-G-Ti composite rods were implanted in the femur of beagle dogs for 3 months. FE-SEM observations demonstrated that needle-like precipitates were deposited on both the surfaces of the composite and bone at the portion having a narrow gap, about 0.1-0.2 mm between them prepared deliberately before implantation. It was found that both the morphologies and the composition of the precipitates in vivo were similar to those in vitro. It is concluded that the HA particles on the surface of the composite act as nucleation sites for precipitation in physiologic environments, whereas the glass matrix is independent to it.

Animals↗

PubMed1994

Radiographic patterns of osteomyelitis in the mandible. Plain film/CT correlation.

Mandibular osteomyelitis often is associated with involvement of the masticator space. Assessment of mandibular osteomyelitis should therefore involve assessment of soft tissue involvement of the lesion. The purpose of this study was to clarify the relationship between computed tomography patterns and the presence of inflammation in soft tissues. Thirty-three cases diagnosed with osteomyelitis of the mandible were analyzed radiologically with conventional radiographs and with computed tomography scans. Computed tomography patterns of osteomyelitis were classified into four types, lytic, mixed, sclerotic, and sequestrum patterns. Location, extent of the lesion, and change of the cortical plate were evaluated and compared with conventional radiographic findings. Mixed pattern cases displayed diffuse bone abnormalities, which sometimes were accompanied by cortical plate disruption and periosteal reaction. In addition, most mixed pattern cases showed soft tissue involvement, especially of the masseter muscle. Inflammation of the masseter muscle was found to be related to periosteal reaction and disruption of the buccal cortical plate. The data demonstrate a close interaction between cortical plate disruption and muscle inflammation. The extent of inflammation including soft tissue involvement was better appreciated with computed tomography in osteomyelitis, especially in mixed pattern cases.

Adolescent↗

PubMed1994

An unusual type of Hangman's fracture with cord compression: a case report.

An unusual case of hangman's fracture with neurologic sequelae is described in a 43-year-old woman. The fracture involved the body of C-2 with gross dislocation of the anterior part of C-2 and C-1 forward on C-3, associated with severe cord compression. The patient was successfully treated with a decompression of the foramen magnum and C-1 laminectomy, accompanying in situ fusion. The images obtained by computed tomography and magnetic resonance imaging were useful in understanding the true nature of the injury and planning the appropriate surgical treatment.

Adult↗

PubMed1994

Increased attenuation in odontogenic keratocysts with computed tomography: a new finding.

An increased attenuation area (IAA) is sometimes seen in the cystic cavity of odontogenic keratocysts (OKCs) on CT scans. The significance of IAA was compared radiologically and histologically in 26 cysts in which a provisional diagnosis of OKC had been made. First, the presence of IAA in the cystic cavity was assessed. Then, relationship between the presence of IAA and data obtained from the cysts, including the CT and histological findings and the visual appearance of the cyst contents, was evaluated. An IAA was frequently seen in large multilocular cysts. There was no relationship between the presence of IAA and aggressive features of the cyst on CT or the cyst contents. Histologically, subepithelial inflammation was often observed in the cysts with IAA. In order to ascertain whether the IAA was due to the keratin mass, a CT scan of a bundle of hair in a water bath was performed and shown to have a similar density. Our study demonstrated that IAA in cystic cavities results from desquamated keratin. Since this seems to occur in long-standing or inflamed multilocular OKCs, it could be used as a significant finding in the diagnosis of OKC.

Adolescent↗

PubMed1994

Spontaneous subperiosteal hematoma of the orbit--case report.

A 62-year-old female was admitted with complaints of sudden proptosis of the left eye and severe left orbital pain without history of trauma or previous illness. Computed tomography and magnetic resonance imaging demonstrated a biconvex extraconal hematoma in the upper part of the left orbit. Surgical exploration of the orbit revealed the presence of a subperiosteal hematoma without a causative lesion. Such spontaneous subperiosteal hematoma of the orbit is extremely rare, but may result from an occult vascular disorder.

Craniotomy↗

PubMed1994

[Traumatic anterior cerebral artery aneurysm difficult to distinguish from congenital cerebral aneurysm: case report].

We report the case of a 29-year-old woman in whom a saccular aneurysm of the distal anterior cerebral artery developed following head trauma due to a car accident. She was semicomatose on admission but had no lateralizing motor signs. Reflexes were symmetrical, with bilateral extensor toe sign. X-ray of the skull showed no fracture but CT scans demonstrated a large frontal hematoma and interhemispheric bleeding. Initial cerebral angiography performed within 12 hours of trauma showed a small protrusion on the pericallosal portion of the left pericallosal artery with no branching point nearby. Angiography was repeated on the 9th day after admission and confirmed the presence of a saccular aneurysm of the pericallosal artery, which had been visible as a small protrusion on the initial angiogram. Traumatic aneurysm was suspected and successful neck clipping of the aneurysm was performed on the 14th day. Preoperative CT and angiographic findings could not rule out a congenital aneurysm but the histological study of the specimen confirmed that it was a traumatic false aneurysm. We discussed the diagnosis and the etiology of posttraumatic aneurysm.

Adult↗

PubMed1994

[Peritumoral hemorrhage after radiosurgery for metastatic brain tumor: a case report].

An unusual case of peritumoral hemorrhage after radiosurgery for the treatment of metastatic brain tumor is reported. This 64-year-old woman had a history of breast cancer and underwent right mastectomy in 1989. She remained well until January 1993, when she started to have headache, nausea and speech disturbance, and was hospitalized on February 25, 1993. Neurological examination disclosed right hemiparesis and bilateral papilledema. CT scan and MR imaging showed a solitary round mass lesion in the left basal ganglia region. It was a well-demarcated, highly enhanced mass, 37mm in diameter. Cerebral angiography confirmed a highly vascular mass lesion in the same location. She was treated with radiosurgery on March 8 (maximum dose was 20Gy in the center and 10Gy in the peripheral part of the tumor). After radiosurgery, she had an uneventful course and clinical and radiosurgical improvement could be detected. Her neurological symptoms and signs gradually improved and reduction of the tumor size and perifocal edema could be seen one month after radiosurgery. However, 6 weeks after radiosurgery, she suddenly developed semicoma and right hemiplegia. CT scan disclosed a massive peritumoral hemorrhage. Then, emergency craniotomy, evacuation of the hematoma and total removal of the tumor were performed on April 24. Histopathological diagnosis was adenocarcinoma. It was the same finding as that of the previous breast cancer. Histopathological examination revealed necrosis without tumor cells in the center and residual tumor cells in the peripheral part of the tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

PubMed1994

[Dilated pericerebellar fluid space in patients with chronic subdural hematoma].

It is not uncommon to observe the dilation of the pericerebellar fluid space (PCFS) on CT in patients with chronic subdural hematoma (CSDH). CT scans of 92 patients with CSDH proven by surgery were reviewed with respect to the dilatation of PCFS and we evaluated the incidence of dilated PCFS and the relationship between PCFS and other factors. There were 68 males and 24 females. Patients ranged in age from 20 to 90 years (mean 65.2 years). Another 50 patients without CSDH were also reviewed as a control group. A new PCFS grading based on the CT findings was proposed, divided into 3 grades as follows. In grade 0, no PCFS could be seen on CT scans. In grade 1, PCFS could be detected along the posterior aspect of the petrous pyramid, and in grade 2, PCFS could be seen not only along the posterior aspect of the petrous pyramid but also under the tentorium cerebelli. The dilation of PCFS was seen in 78 patients (84.8%) out of the 92 cases. In 50 patients without CSDH (control group), the dilatation of PCFS was noted only in 6 (12%). The dilatation of PCFS was almost always seen on the same side as the CSDH. Among many factors, the significant factor was the degree of the midline shift, the bigger the midline shift caused by CSDH, the larger was the dilated PCFS. Although the mechanism of the dilated PCFS in patients with CSDH is not clear, it is postulated that the mechanism is caused by CSF flow disturbance, compression or adhesion of the subarachnoid space due to CSDH.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Analysis of maxillary sinusitis using computed tomography.

Odontogenic maxillary sinusitis can be defined as sinusitis induced by a dental lesion. We examined the CT findings of 68 patients with maxillary sinusitis in order to differentiate between inflammation of sinus origin and inflammation of dental origin. Maxillary sinusitis was classified into four types according to clinical symptoms, history and conventional radiographic findings: type 1, simple sinusitis; type 2, odontogenic sinusitis; type 3, mixed sinusitis; type 4, slight sinus abnormality with a dental lesion. The relationship between the type of maxillary sinusitis and CT findings was analysed. Type 1 sinusitis exhibited severe pathological changes in both mucosa and bone which often extended into the nasal cavity and other paranasal sinuses. Type 2 sinusitis exhibited localized pathology on the unilateral antral floor. Type 3 sinusitis exhibited severe pathology characteristic of type 1 combined with type 2 sinusitis. Type 4 sinusitis could be differentiated by the CT findings into type 1 or type 2 sinusitis. The classification of sinusitis in this manner has implications for treatment planning, and CT should therefore be performed when conventional radiography does not provide sufficient information.

Female↗

PubMed1993

Factors affecting the transformation of octacalcium phosphate to apatite in vitro.

A fresh octacalcium phosphate (OCP) precipitate without drying and three kinds of dried OCP powders were soaked for 3 weeks in 11 kinds of physiological solutions consisting of different combinations of Ca2+, Mg2+, K+, Na+, HCO3-, HPO4(2-), F-, albumin, collagen and alkaline phosphatase, in three different pH values and at three different temperatures. X-ray diffraction study showed that most of the OCP had been transformed to apatite with low crystallinity after soaking in the solutions without Mg2+. The IR absorption spectra revealed that CO3 was incorporated in the apatite formed from OCP in the solution without Mg2+, whereas OCP changed little after soaking in the solution containing Mg2+. These results suggest that the presence of Mg2+ in the solution is one of the most effective means of inhibiting the transformation of OCP to apatite by interrupting the precipitation process of apatite.

Analysis of Variance↗

PubMed1993

Application of generalized estimating equations to a study of in vitro radiation sensitivity.

We describe an application of the generalized estimating equation (GEE) method (Liang and Zeger, 1986, Biometrika 73, 13-22) for regression analysis of correlated Poisson data from a split-plot design with a small number of experimental units. As an alternative to the use of an arbitrarily chosen working correlation matrix, we demonstrate the use of GEE with a reasonable model for the true covariance structure among repeated observations within individuals. We show that, under such a split-plot design with large clusters, the asymptotic relative efficiency of GEE with simple (independence or exchangeable) working correlation matrices is rather low. We conclude by summarizing issues and needs for further work concerning efficiency of the GEE parameter estimates in practice.

Biometry↗

PubMed1993

[Complication of gastro-duodenum with intra-hepatic arterial infusion chemotherapy using implantable reservoir system for hepatic tumors].

The subjects were 20 cases with implantable reservoir systems for unresectable hepatic tumors. We evaluated the correlation between a complication of the gastro-duodenum after intra-hepatic arterial chemotherapy and a gastro-duodenal distribution of anti-cancer drugs using the hepatic perfusion scintigram by 99mTc-macroaggregated albumin via reservoirs. The 20 cases were divided into 3 groups (A, B, C) according to the level of gastro-duodenal accumulation of 99mTc-MAA. In group A with the strongest accumulation in the gastro-duodenum, we frequently found a gastro-duodenal ulcer after intra-hepatic arterial chemotherapy. There was a significant difference between group A and group C, the latter without a gastro-duodenal accumulation. These results suggested that the hepatic perfusion scintigram via reservoir was a useful examination to expect and prevent the complication of gastro-duodenum on intra-hepatic arterial infusion (especially continuous infusion) chemotherapy.

Carcinoma, Hepatocellular↗