Biomedical subjects

H Bussaka

Publications and source records attributed to H Bussaka.

63 records · Page 4Linked to original sources

PubMedDate not supplied

Intraarterial digital subtraction angiography vs conventional angiography of abdominal diseases.

Seventy-five patients with various abdominal diseases were studied by intraarterial digital subtraction angiography (IA DSA) during conventional abdominal angiographic examinations. The image quality, tumor stain, and arterial encasements were evaluated and diameters of vessels visualized by IA DSA were measured. The vessels greater than 2.0 mm or more in diameter were equally well demonstrated on IA DSA. IA DSA demonstrated tumor stains and portal system to good advantage. Real time imaging was also advantageous during an embolization procedure.

Abdominal Neoplasms↗

PubMedDate not supplied

High resolution DSA: experimental and clinical evaluation.

The DSA system has been upgraded for capabilities of slow scan video technique and progressive T.V. read-out of 1024 X 1024 matrix with 10 bits of depth. A square wave test pattern made of lead bar demonstrated moderate improvement in spatial resolution, but imaging of a Burger-Rose phantom revealed no significant increase in contrast resolution. Clinical study of various angiograms with intraarterial injections showed that there was slight improvement in the visibility of the vessels, especially small arterial branches, while there was no increase in visibility of the veins. There were no cases in which diagnoses were altered by application of high resolution DSA. With future improvements of the image intensifiers, DSA with 1024 X 1024 matrix may reveal its potential advantage, especially when coupled to larger image intensifiers such as 12 or 14 in.

Angiography↗

PubMedDate not supplied

Determination of left ventricular volumes with use of DSA density values.

A computer program was developed to obtain left ventricular volumes from the density values of DSA. The highest density value along the horizontal pixel line over the left ventricle in 30 degrees RAO was considered to correspond to the greatest width on the same level of 60 degrees LAO. The left ventricular volume was obtained by converting the density values into the width and integrating these values. This method estimated experimental balloon volumes with considerable accuracy. Clinical evaluation revealed good correlation between DSA and conventional cine left ventriculography.

Angiography↗

PubMedDate not supplied

MR visualization and clinical significance of the anterior longitudinal epidural venous plexus in cervical extra-axial lesions.

A thin band of intermediate signal intensity behind the cervical vertebral bodies, demonstrated on sagittal MR images, was attributed to the anterior longitudinal epidural venous (AEVP). Percentage visualization and clinical significance of this structure were evaluated in extra-axial lesions of the spinal cord. In review of 50 normal controls, the percentage visualization of this structure at each cervical vertebral level was 25.5% on T1 weighted sagittal SE images, while that of T2 or proton density weighted SE images was 26.0%. AEVP was demonstrated by sagittal MRI in 29 of 128 extra-axial lesions of the cervical cord (22.7%), including cervical spondylosis, ossification of the posterior longitudinal ligament (PLL), herniated disk and spondylosis at a single level. AEVP in these conditions was often thickened compared with normal controls, probably due to venous engorgement and contribution of the dura mater and PLL. Posterior displacement of this structure or "lifted band appearance" indicated herniated disk or posteriorly protruding osteophyte, demonstrating true anteroposterior diameter of the spinal canal. Demonstration of AEVP on sagittal MRI was important in the diagnosis of extra-axial lesions of the cervical cord.

Cervical Vertebrae↗

PubMedDate not supplied

Digital TV tomography: description and physical assessment.

A digital TV tomography system, capable of retrospective reconstruction of multiple digital tomographic images, has been developed and its basic physical characteristics have been evaluated. The multiple tomographic images were formed through retrospective reconstruction of digital data acquired on a linear tomographic x-ray unit and an image intensifier-television system. Digital data were obtained with a series of 30 pulsed exposures during linear motion of the system. A distortion correction algorithm for the convex surface of the image intensifier was developed in order to reduce image distortion. A phantom study showed that the square-wave response at the fulcrum plane was slightly inferior to that in conventional tomography. There was also a slight decrease in the square-wave response away from the fulcrum plane and upon application of a correction algorithm, as compared with the response of the original reconstructed image at the fulcrum plane. The exposure dose for a single image was approximately half that in conventional tomography. Because of many advantages, including low exposure, short examination time, digital image manipulation, and applicability to picture archiving and communication systems, this is likely to become an important method in radiology when further technical refinements have been made.

Angiography, Digital Subtraction↗

PubMedDate not supplied

Clinical evaluation of digital TV tomography.

A unit for digital TV tomography (DTT) was constructed on the basis of retrospective reconstruction of digital data acquired during a linear tomographic motion of an X-ray tube and an image intensifier with a television camera (I.I.-TV) assembly. Following descriptions of the basic principle and system, clinical results obtained with this unit are presented. Comparison with conventional tomography of the chest, skull, abdomen, and bones and joints showed equal diagnostic information in more than 50% of cases. Application to intra-arterial and intravenous DSA provided excellent images, but no new information was obtained. DTT has the advantages of technical simplicity, short examination time, low exposure dose, and compatibility with a PACS system. This technique will become an important part of a modern radiology department.

Aged↗

PubMedDate not supplied

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

Percutaneous transluminal angioplasty has been widely used for dilatation and recanalization of occluded or stenosed vessels, but clinical experience in Japan is not extensive. Follow-ups of 78 ilio-femoro-popliteal angioplasties were performed for up to 51 months to assess the initial and long-term results. The initial technical success rate was 91%. The three-year cumulative patency rate was 75%. This study demonstrates that the long-term results of PTA of ilio-femoro-popliteal arterial lesions are competitive with reconstructive surgery. PTA should be the treatment of choice in patients with atherosclerotic narrowing or occlusion of the lower extremities.

Aged↗

PubMedDate not supplied

Evaluation of prototype equipment for digital subtraction angiography in diagnosing intracranial lesions.

Two prototype units for digital subtraction angiography have been developed by Japanese manufacturers. Their performance in demonstrating various intracranial lesions in 121 patients was evaluated. Comparison with conventional selective catheter angiography was possible in 77 patients. Digital subtraction angiography proved useful in preoperative evaluation of pituitary tumors when transsphenoidal surgery was being considered; demonstration of faint tumor stains which might be missed on conventional angiography; demonstration of larger aneurysms, arteriovenous malformations, and tumors as a screening technique; demonstration of abnormalities involving the dural sinuses; and follow-up of patients after surgery or embolization.

Brain Diseases↗

PubMedDate not supplied

Iotrolan: a blood-isotonic nonionic dimer contrast agent for peripheral angiography.

Twenty-four patients undergoing peripheral arteriography with iotrolan 280, a blood-isotonic, nonionic, dimeric contrast medium, were evaluated in a carefully controlled phase III open trial using a variety of objective and subjective tests of discomfort. There was almost no evidence of pain, and the patients reported that they had minimal warm sensation during injection. No abnormalities in blood chemistry or urinalysis were noted in relation to injection of the contrast medium. Opacification of the peripheral arteries was excellent in all patients. Multiple physical examinations, chemical tests, electrocardiograms, and monitoring of the blood pressure showed that iotrolan 280 was a safe and useful contrast agent for peripheral angiography.

Adult↗