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Biomedical subjects

H Bussaka

Publications and source records attributed to H Bussaka.

At least 19 recordsLinked to original sources
PubMed1998

Dural carotid cavernous fistulas: role of conventional radiation therapy--long-term results with irradiation, embolization, or both.

PURPOSE: To evaluate the long-term results of irradiation alone or of embolization with or without irradiation in patients with dural carotid cavernous fistulas (DCCFs). MATERIALS AND METHODS: Between 1984 and 1996, symptomatic DCCFs in 26 patients were treated by using irradiation alone (protocol 1, n = 12) before April 1988 and by using embolization as an initial treatment (protocol 2, n = 14) during and after April 1988. When angiography showed no improvement after embolization, irradiation was added (n = 6). On the basis of drainage flow speed, DCCFs were classified as fast, medium, or slow. RESULTS: With irradiation alone, all six patients with slow- to medium-type DCCFs had cure with a mean follow-up of 62 months. Four of six patients with fast-type DCCFs had cure or improvement, but the remaining two had no change. In the embolization group, irradiation was added in six patients with fast-type DCCFs. With a mean follow-up of 24 months, four of the six patients had cures, one had improvement, and one had no clinical change. Those who underwent protocol 2 had cures significantly earlier than those who underwent protocol 1 (P < .05). CONCLUSION: Conventional radiation therapy resulted in cure of DCCFs in nine (75%) of the 12 patients and in improvement of signs and symptoms in one (8%). Fast-type DCCFs may not always be improved. Radiation therapy may be useful in DCCFs after embolization.

Adult↗
PubMed1996

Basic imaging properties of a new screen-film system for chest radiography.

To evaluate the potential clinical usefulness of a new screen-film system (advanced screen-film system; AD system) for chest radiography, its fundamental imaging properties compared with a conventional screen-film system (HR-4/HR-S) were investigated. The basic imaging properties were evaluated by measuring characteristic (H&D) curves, relative speeds, MTFs (modulation transfer functions), WS (Wiener spectra), and x-ray attenuations of screens. The detail visibilities and pathological details of various diseases in chest radiographs of patients were evaluated subjectively. The film gradient of the AD system was slightly lower at low radiographic density, and higher at high density, as compared with a conventional screen-film system. The screen speed of the AD system was 212% greater than that of the conventional system, and the film speed was 53% that of the conventional film. As the result, the total speed of the AD system was slightly higher compared with the conventional system. The spatial resolution of the AD system was comparable to or slightly lower than that of the conventional system. The noise level of the AD system was considerably lower than that of the conventional system at low (D = 0.5) and middle (D = 1.0) radiographic density levels. However, it was high at high radiographic density (D = 1.8). The radiographic densities in the underpenetrated areas with the AD system were greater than those of the conventional system when the lung densities are matched comparable. Improvement in noise level with the AD system at low and middle density levels may be useful for detection of various diseases in chest radiographs.

Equipment Design↗
PubMed1994

[Percutaneous transluminal angioplasty of the ilio-femoro-popliteal arteries: initial and long-term results].

The initial and long-term results of percutaneous transluminal angioplasty (PTA) were assessed in 254 atherosclerotic lesions of the ilio-femoro-popliteal arteries in 130 patients. There were 122 men and 8 women, aged 36-85 years (average, 68 years). Follow-up periods ranged from 1 to 131 months, with a mean of 42 months. PTA was performed in 6 patients in Fontaine's stage I, 112 patients in stage II, and 12 patients in stage III-IV. We reported initial success rates of 92%, 58%, 83% and 74% for iliac stenosis, occlusion, femoro-popliteal stenosis and occlusion, respectively. Overall, the initial success rate was 82% (203/247). The 5-year patency rates according to Kaplan-Meier analysis were 70%, 69% and 63% for iliac stenosis, occlusion and femoro-popliteal stenosis, respectively. In femoro-popliteal occlusion, the 1-year patency rate was 42%, which was significantly worse than that for stenosis (P < 0.01). The longest patency periods obtained were 131 months in the iliac artery, and 106 months in the femoro-popliteal artery. The recurrence rate within 6 months was significantly higher in patients with diabetes. The recurrence rate between 6 and 12 months was significantly higher in patients with poor run-off, and those of advanced age.

Adult↗
PubMed1994

[Preliminary clinical applications of asymmetric screen-film systems in chest radiography].

The physical imaging properties of asymmetric systems and a conventional system were evaluated by measuring characteristic curves, resolution properties and noise Wiener spectra. The potential clinical application of asymmetric screen-film systems was studied by evaluating the visibility of the anatomical structures and various types of abnormalities in comparison with those of a conventional screen-film system. The asymmetric systems showed a wider dynamic range than the conventional system. The resolution properties of asymmetric systems depend on the combination of front and back screens used. Chest radiographs obtained with asymmetric systems improved the visibility of the mediastinal area. The visibility of the lung field in the asymmetric systems was slightly inferior to that with the conventional system when the same tube potential was used. However, the image quality and visibility of various abnormalities showed greater improvement with the asymmetric systems when a lower tube potential was applied. We conclude that the selection of radiographic techniques and combination of screens are important for the clinical use of asymmetric systems.

Humans↗
PubMed1994

[Percutaneous transluminal angioplasty of the subclavian arteries].

We studied the complications and long-term results of percutaneous transluminal angioplasty (PTA) of subclavian artery stenosis in 11 patients. In all patients but one, the systolic blood pressure before PTA in the arm on the involved side was at least 30 mmHg lower than that in the opposite arm. PTA of 11 left subclavian arteries and one right subclavian artery was attempted. Five of the patients suffered from symptoms of vertebrobasilar insufficiency as well as ischemia of the upper limb, two had only cerebral symptoms, two had only ischemia of the upper limb, and another had no symptoms related subclavian arterial lesion. Standard techniques for PTA were employed, using the femoral route eight times and the axillary route four times. Angioplasty was successful in 11 lesions (92%). In the successfully treated patients, the blood pressure in the ipsilateral arm was significantly increased after PTA. No complications occurred during or after the procedure. The patients were followed for 2-74 months (mean 25.7 months). During this time, no recurrence of the stenosis was observed, although the symptoms of vertebrobasilar insufficiency did not always improve. These results suggest that PTA is useful for treating subclavian artery stenosis.

Adult↗
PubMed1992

Evaluation of oil-soluble FUdR ester for transcatheter arterial treatment of hepatomas.

From January 1987 to December 1989, we performed a prospective study of transcatheter arterial chemoembolization therapy with iodized oil (Lipiodol) mixed with an anticancer agent. A new oil-soluble modification of FUdR, FUdR-C8 ester, was developed and dissolved in Lipiodol as an embolic material, which was administered to 36 patients with hepatomas. Water-soluble adriamycin emulsified in Lipiodol was used as control in 67 patients with hepatomas. Initial effects on tumors were observed as decrease of tumor size in 25.0% for the FUdR group and 17.9% for the control group. Alpha-fetoprotein decreased more than half in 41.9% of the FUdR group, and 16.1% of the ADM group. Six-month and one-year survivals were 74.2% and 46.8% for the FUdR group (median survival 317 days), whereas the control group yielded 61.0% and 28.3% survivals, respectively (median survival 191 days).

Carcinoma, Hepatocellular↗
PubMed1992

Percutaneous transluminal angioplasty: pain during balloon inflation.

The pain during the balloon dilatation of angioplasty was evaluated prospectively to assess its clinical significance. In 54 angioplasties, no pain was observed in 54%, mild pain in 20%, moderate pain in 11% and severe pain in 15%. Moderate or severe pain was observed in 39% of 28 iliac angioplasties and in 7% of 14 femoral angioplasties. There was a significant difference between the two groups. We did not find any significant correlation between the severity of pain and stenotic ratio before angioplasty. Severe pain may be a warning of severe dissection; in our study, all severe dissections were accompanied by severe pain without arterial rupture.

Angioplasty, Balloon↗
PubMed1991

[CT appearance of small renal angiomyolipoma].

Twenty-six small renal angiomyolipomas (AML) in 21-patients, detected incidentally by ultrasonography, were evaluated with CT. Conventional CT findings of AML were classified into three types by the degree of the fatty areas in the mass. Type 1 is a mainly fat density mass like a lipoma observed in 7 lesions (26.9%). Type 2 is a fatty mass intermixed with areas of tissue density and found in 15 lesions (57.7%). Type 3 is a mass without fatty portion and observed in 4 lesions (15.4%). These latter lesions were indistinguishable from renal cell carcinoma on CT. It is important to diagnose a small lesion of the kidney as AML correctly for proper treatment.

Adult↗
PubMed1991

Development of a ceiling-suspended angiographic unit for interventional neuroradiology.

A new neuroangiographic unit was developed with a ceiling-suspended gantry, capable of rotation (110 degrees) and craniocaudal angulation (+/- 45 degrees) along the body axis. The gantry could also be rotated 225 degrees at the ceiling suspension axis and sidetracked away from the angiographic table in case of emergency. Two sets of a twin-focus X-ray tube and a 12-inch image intensifier (II) were mounted on the gantry in the isocentric and cross-firing positions. High resolution 1024 x 1024 matrix digital radiography was obtained with a speed of 30 frames/s, while conventional film-screen radiography was obtained at 4 films/s. Rapid film changers were installed and interchangeable with the IIs. The lateral II and X-ray tube could be positioned from either side of the patient. There was no angulated position of the lateral imaging system during angulated anteroposterior or Towne projection of the frontal imaging system. Automatic repositioning of the gantry was possible to the preset position. Stereoscopic, magnification and stereoscopic magnification radiography could be obtained easily in monoplane or biplane mode. Switching from fluoroscopy to radiography and vice versa was possible rapidly and easily. Neuroangiographic as well as interventional procedures were performed expeditiously with lower complication rates. Suspending the gantry from the ceiling made more space available on the floor for the anesthesiologists.

Angiography↗
PubMed1991

Normal and abnormal pituitary glands: gadopentetate dimeglumine-enhanced MR imaging.

Dynamic magnetic resonance (MR) imaging with a 1.5-T superconductive unit was used in the evaluation of nine normal pituitary glands and 10 pituitary adenomas, including four microadenomas and six macroadenomas. Seven to 10 images were obtained every 20-30 seconds with use of the spin-echo technique after rapid injection of gadopentetate dimeglumine. The earliest contrast material enhancement of normal structures was seen in the infundibulum and posterior lobe of the pituitary gland at 20 seconds, followed by gradual contrast material enhancement of the anterior lobe of the pituitary gland from the junction of the infundibulum to the peripheral portion of the anterior lobe of the pituitary gland within 80 seconds after gadopentetate dimeglumine injection. The peak enhancement of pituitary adenomas occurred at 60-200 seconds, usually after the most marked enhancement of the normal pituitary gland. Microadenomas are best visualized at earlier phases of gadopentetate dimeglumine-enhanced dynamic imaging, with signal intensity lower than that seen on images of normal pituitary glands.

Adenoma↗
PubMed1990

[Lateral position of the external carotid artery].

Lateral position of the external carotid artery was seen in 17 cases (4.3%), of which 13 cases were on the right side and 4 cases on the left. It is necessary to know the lateral position of the external carotid artery for the correct diagnosis by IVDSA and doppler scanning.

Aged↗
PubMed1990

[Cerebellar infarction; the findings of CT, MRI and cerebral angiography].

The findings of CT, MRI and cerebral angiography were analysed in 18 cases with cerebellar infarction, of which 10 were men and 8 women. The areas of infarction were as follows; PICA in 9 cases, SCA in 8 cases, AICA and diffuse type in one case each. One case had two lesions. CT showed low density areas in 15 cases after 24 hours of the onset, but an abnormality was not demonstrated in one case which had an infarction of PICA area. MRI showed a high-intensity lesion on T2 weighted image during the first and tenth day after the onset, while a low-intensity lesion on T1 weighted image and high-intensity lesion on T2 weighted image were demonstrated after seventh day. MRI revealed the area of infarction better than CT. Vertebral angiography and DSA showed narrowing or poor visualization of the cerebellar arteries in 5 cases but this finding was not shown in 3 cases which were examined by IVDSA.

Adult↗
PubMed1989

Intraarterial infusion of 5-fluoro-2-deoxyuridine-C8 dissolved in a lymphographic agent in malignant liver tumors. A preliminary report.

The drug 5-fluoro-2-deoxyuridine-C8 (FUdR-C8), one of the lipophilic prodrugs of FUdR, was dissolved in an oily lymphographic agent (Lipiodol Ultra Fluid, Andre Gelbe Laboratory, Paris, France; Ethiodol, Savage Laboratories, Melville, NY) and used for the intraarterial treatment of malignant liver tumors. From August 1985 to June 1988, 33 patients with hepatocellular carcinoma and 13 patients with metastatic liver tumors were treated with this agent at the Kumamoto University Hospital and its affiliated hospitals. The response rate (complete remission [CR] and partial remission [PR]) was 27.6% for hepatocellular carcinomas and 46.1% for metastatic liver tumors. The cumulative 1-year survival rate was 55.1% for hepatocellular carcinomas and 70.0% for metastatic liver tumors. More than a 50% decrease in the tumor marker level was observed in ten of 21 patients with hepatocellular carcinoma and in two of eight patients with metastatic liver tumors. The side effects, which were transient and controlled with conservative treatment, included fever, abdominal pain, nausea, vomiting, and acute gastritis.

Adult↗
PubMed1989

[Angiographic positions for thoracic outlet syndrome].

Thirty four patients (18 males and 16 females, 54 lesions) with thoracic outlet syndrome (TOS) were studied with conventional angiography. Angiography in the supine position did not confirm subclavian artery compression in 43.4% of patients. Lordotic position or upright position was useful for demonstration of subclavian artery compression in patients who did not show any findings in conventional techniques.

Adolescent↗
PubMed1989

[Percutaneous transluminal renal angioplasty: indication for renovascular hypertension associated with renal atrophy].

The results of clinical studies indicate that percutaneous transluminal renal angioplasty (PTRA) is an effective means for treating renovascular hypertension resulting from renal artery stenosis. However, the indications for the patients with renal failure or renal atrophy are not established on a firm ground. We attempted PTRAs of ten kidneys in nine patients with hypertension associated with renal atrophy. They were followed for an average of 8 months by the methods including blood pressure, angiography or DSA, blood chemistry, and RI-renogram. We also evaluated enlargement of the renal size on an angiogram or on a plain film at DSA. Angiographic follow-up showed persistent relief of the stenosis in all cases. After PTRA, blood pressure reduced to normal or improved in two thirds of the patients for the follow-up period. In the study of three patients with excellent results for blood pressure, two patients showed the renal length to be increased by 1.0 cm or more, and one patient by 0.5 cm. In the same group, RI-renogram also showed good response. These data indicate that PTRA could improve total perfusion on the affected kidneys. On the other hand, in three patients with no change in blood pressure, there was poor response in both the renal size and the data of RI-renograms. We suggest that the irreversible changes might have occurred in these kidneys. It was difficult to predict cure group from no change group before PTRA.

Adult↗
PubMed1989

[Localization of spinal tumors by MRI].

Exact localization of the spinal tumors is particularly important for differential diagnosis and surgery. Therefore, it was attempted to evaluate the diagnostic accuracy of MRI in localizing the spinal tumors exactly. Nineteen cases of spinal cord tumors, being localized in the intradural extramedullary, extradural and both intradural and extradural spaces, were studied with MRI. Intradural extramedullary tumors showed small CSF spaces just below and above the tumor which were demonstrated as CSF intensity on T1 and T2 weighted images. Although extradural tumors did not show CSF spaces, there was extradural sign or dural density between the tumor and the spinal cord. Intradural and extradural tumors were outlined as having both characteristics. Signal intensities of the spinal tumors were not characteristic for specific histology. Gd-DTPA was quite useful for accurate localization of the tumors. In comparison with myelography, MRI was superior to myelography in extradural tumors and equally useful for intradural and extradural tumors, but it was less diagnostic in intradural extramedullary tumors. In general, MRI was quite useful in localizing the spinal tumors exactly and the accuracy of MRI was quite high. In the near future this technique will replace myelography and other radiologic methods.

Adult↗
PubMed1988

Depth determination on stereoscopic digital subtraction angiograms.

The determination of depth on stereoscopic digital subtraction angiographic (DSA) images was evaluated. A "plus" phantom that contained simulated blood vessels of various sizes with various concentrations of contrast medium was used for the study. The vessels ranged in diameter from 0.46 to 1.35 mm, with concentrations of contrast material of 1.6%-25%. The images were evaluated by seven radiologists and six radiologic technologists. The detectability of depth separation increased as the iodine concentration and the vessel size increased. With stereoscopic DSA, correct identification of depth is possible more than 80% of the time for vessels approximately 1 mm in diameter and containing 3.1% contrast medium when the vessels are separated by more than 2.8 mm.

Angiography↗