H. Bussaka

Increased MR signal intensity secondary to chronic cervical cord compression

SummaryMagnetic resonance images of 128 patients with compressive lesions of the cervical spinal canal were reviewed to determine whether a high signal intensity lesion within the spinal cord was present on T2 and proton density weighted spin echo images. Such high signal intensity was observed in 24 cases or 18.8%. The incidence was higher in herniated disk (32.4%), atlanto-axial dislocation (28.6%), and ossification of the posterior longitudinal ligament (22.7%), whereas the abnormality was found sporadically in cervical spondylosis and vertebral body tumors. The high intensity lesion on T2 weighted images was generally observed in patients with constriction or narrowing of the spinal cord. The lesion was not demonstrated on T1 weighted spin echo images. Spinal cord constriction or localized narrowing seemed to be the most important portant predisposing factor in producing such a high signal intensity. The pathophysiologic basis of such an abnormality was presumed to be myelomalacia or cord gliosis secondary to a long-standing compressive effect of the spinal cord.

Cerebral vasculitis secondary to Wegener's granulomatosis: computed tomography and angiographic findings

The central nervous system is rarely involved by Wegeners granulomatosis. A case of Wegeners granulomatosis with involvement of the cerebral arteries was reported. Computed tomography showed extensive brain edema with angiographic demonstration of cerebral vasculitis.

Development of a ceiling-suspended angiographic unit for interventional neuroradiology

SummaryA new neuroangiographic unit was developed with a ceiling-suspended gantry, capable of rotation (110°) and craniocaudal angulation (±45°) along the body axis. The gantry could also be rotated 225° 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 1024×1024 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 Hs. 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.

Balloon-occluded arterial infusion therapy in the treatment of primary and recurrent gynecologic malignancies

Balloon-occuluded arterial infusion (BOAI) of bilateral internal iliac arteries produces high drug concentration as well as increased arterial flow of pelvic organs. Twenty-seven patients with primary and locally recurrent gynecologic malignancies were treated with BOAI of cisplatinum. Six of 10 patients with primary advanced uterine cancer and 5 of 11 patients with recurrent cancer showed clinical response. In 6 patients, BOAI was performed as an adjuvant therapy to radiation or other chemotherapy. Toxicity was similar to that seen with systemic treatment using cisplatinum, but its frequency and degree were less severe.

Evaluation of the cerebral vasculature by intraarterial DSA - with emphasis on in vivo resolution

SummaryComparative study was performed between IA DSA and stereoscopic magnification angiography in relation to small vessel resolution, image quality of the vessels and image quality of various pathologic lesions. The vessels of various diameters, accurately measured by stereoscopic magnification angiography, were localized on IA DSA and their resolution was carefully assessed. The vessels more than 1 mm in diameter were equally visualized on IA DSA and conventional angiography. The vessels between 1 mm and 0.5 mm showed fair resolution on IA DSA, whereas IA DSA did not resolve the vessels smaller than 0.5 mm in diameter to good advantage. In addition, image quality of the vessels on IA DSA was compared with the conventional methods. Cerebral gyrus, venous sinuses, and intracerebral veins are often shown better on DSA. The small vessels such as lenticulostriate, small cortical, thalamoperforate and meningohypophyseal arteries were not defined on DSA. Equal or better image quality was obtained in more than 85% of cases with pathologic lesions. Examinations were performed faster with lower cost and lower complication rate. Information provided by DSA was often sufficient for managements of patients. Combined use of DSA and conventional angiography will improve diagnostic accuracy and decrease the complication rate.

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.

The value of Digital subtraction angiography in peripheral vascular diseases

The iliac and subclavian arteries and their distal branches were studied by digital subtraction angiography (DSA) in 79 patients and the results compared with conventional angiograms for 35 patients. Techniques, results, advantages and disadvantages are described. DSA (both intravenous and intra-arterial) looks very promising in the diagnosis of peripheral vascular disease.

Stereoscopic DSA of the central nervous system

SummaryStereoscopic DSA is performed with alternate exposures from a twin focal X-ray tube (6,5 cm focal separation). Excellent intravenous and intraarterial DSA images of the cerebral vessels are obtained with separation of overlapping parts of the normal and abnormal vasculature. The clinical value of DSA has been enhanced by use of stereoscopic DSA.

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.

Development of a new universal neuroangiographic unit

SummaryA new neuroangiographic unit has been developed with use of a “C” type gantry, which is capable of rotation and angulation for various angiographic projections. Two sets of a twin focal X-ray tube and an imaging system are mounted on the gantry. Each imaging system consists of a 9 inch image intensifier and a 14 x 14 rapid film changer, which can be exchanged in position rapidly. Stereoscopic magnification and stereoscopic contact angiography, fluoroscopy and DSA are performed in monoplane and biplane and switched over to each other expeditiously and easily. The detailed angiographic information is obtained with lower complication rate and lower exposure to patients. Interventional neuroradiologic procedures are performed efficiently on this unit.