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Conventional arteriography and intraarterial digital subtraction arteriography (IADSA) were compared in 36 patients with primary bone or soft-tissue tumors of the extremities. The sensitivity of IADSA was at least equal to conventional arteriography for demonstrating normal or abnormal major arteries and feeding arteries, equal to or superior for depicting tumor stains or draining veins, but slightly inferior for revealing minute tumor vessels. An increase of the matrix size from 256 X 256 to 512 X 512 improved these sensitivities. IADSA with 15% diatrizoate contrast material eliminated the contrast material-induced pain in all patients. With a computer-controlled iris setting, an average of 5 minutes of procedure time and 1.7 R of radiation (0.44 mC kg) per examination could be saved. IADSA reduced the cost of an examination by an average of $67. The results indicate that IADSA was diagnostic in all instances and can replace conventional arteriography for the evaluation of extremity tumors.

The computed tomographic (CT) findings of two popliteal cysts are presented, and the correlated anatomico-pathologic changes are discussed. The characteristic findings include thin, well-defined cyst wall, fluid density contents, central septum or septi, and medial popliteal location with mediocaudal extension. These findings, however, may vary due to herniation or rupture of the synovial membrane, gelatinous cyst contents, or metaplastic change of the cyst wall. Differential diagnoses include liposarcoma, popliteal aneurysm or hematoma, thrombophlebitis, xanthoma, fibrosarcoma, or other soft tissue tumors.

The preoperative diagnosis of abdominal cerebrospinal fluid pseudocyst, in association with ventriculoperitoneal shunts, was made in two patients. Computed tomography and/or ultrasound and radiologicol procedures of choice to demonstrate and localize these cysts.

CT examination of 71 patients with cerebral hemiatrophy revealed dilatation of the ventricle and low density of the cortex of the involved side in all cases. Thickening of the calvarium and a shift of the midline were found in about half of the patients.

Myelographic changes after spinal operation are often difficult to interpret especially with regard to the differentiation between arachnoiditis and recurrent disc prolapse. The radiological appearances using iophendylate (Myodil) and the distinguishing features are discussed and illustrated.

Familial polyposis coli and Gardner's syndrome have identical colonic manifestations. Recent evidence has shown that both conditions are associated with occult osteomatous lesions in the mandible. We present 3 patients from 2 families with familial polyposis coli who, in addition to the colonic lesions, also had occult osteomatous mandibular lesions. The value and practical application of radiography of the mandible as an additional diagnostic aid in familial polyposis coli are emphasized.

One of the most effective treatment modalities for tumors of the head and neck has been radiation therapy. In a small number of cases, delayed radiation necrosis of the brain is a dreaded and devastating complication of radiation therapy. The imaging studies (radionuclide brain scan, cerebral angiography, computed tomography and magnetic resonance imaging) in 12 cases of histologically proven, delayed radiation necrosis of the brain are analysed. While both computed tomography and magnetic resonance imaging can depict radiation necrosis with great sensitivity, however, the ability of these imaging techniques to differentiate between radiation necrosis and recurrent or residual brain tumor is low.

Two cases of leukaemic infiltration of the stomach are presented. In both patients the dominant presenting sign was gastro-intestinal bleeding. The clinical, radiological and pathological findings are presented together with a brief review of the literature.

Craniopharyngiomas present a diverse appearance on computed tomography. Histological diagnosis is not always possible, but computed tomography is of great assistance in the delineation of the tumour as well as of the degree of associated hydrocephalus. Computed tomography also enables rapid non-invasive follow-up after surgery or radiotherapy, or both.

The computed tomographic findings in 54 patients with intracranial meningioma are presented. Computed tomography is a rapid, noninvasive and highly accurate method of diagnosing intracranial meningioma and, in most cases, the findings are specific for this tumor.

The continuing increase in diagnostic examinations using digitally formatted image instrumentation imposes new requirements on the acquisition, display, transmission, recording, and archiving of all diagnostic data. The fabrication decisions and initial clinical testing of a prototype on-line, decentralized digital image management system are described. With this system, raw digital data can be viewed by multiple users as soon as it is acquired by an acquisition node and transmitted to a display node. Radiologists and clinicians have given this system a favorable reception.

Digital medical imaging modalities construct and display images as cross-sections of anatomy. The technologies of these digital imaging systems are moving towards thinner cross-section thicknesses, higher spatial resolutions, and larger dynamic ranges. These imaging modalities provide cross-sectional displays in which there is no superimosing of organs. This provides relatively precise two-dimensional geometric information. In regarding the general three-dimensional (3-D) space relationships among a number of anatomic structures is difficult to acquire from a large number of thin serial sections. Clinicians are required to visualize such information by mentally stacking these serial sections to obtain the complete structure. A number of 3-D surface reconstruction algorithms have been developed for displaying 3-D anatomic structures on raster graphic displays. This paper will present a comparison among these reconstruction algorithms for: (1) computation time; (2) algorithm complexity; (3) computer storage requirements; and (4) clinical efficacy. The authors will report on a three-year study of the clinical utilization of 3-D display algorithms using raster graphic display systems.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The computed tomography (CT) findings in 5 patients with tuberous sclerosis are presented. CT is recommended as a rapid, non-invasive, easily repeated investigative procedure for patients with clinically suspected tuberous sclerosis and epilepsy of unknown origin.

Computed tomography (CT) has revolutionized the diagnosis of diseases affecting the vertebral column. CT effectively demonstrates the bony vertebral column with its intervertebral articulations, its soft tissue contents, and the surrounding paravertebral soft tissues. The vertebral column may be the site of involvement of a wide variety of benign diseases. These diseases may be congenital or acquired and may arise from within the spinal canal, from the vertebrae themselves, or from the paravertebral soft tissues. These lesions may be unsuspected clinically and may be detected incidentally in patients undergoing CT of the spine for nonspecific complaints. The axial projection is extremely useful in displaying spinal anatomy and pathology and, combined with sagittal and coronal reformation, provides diagnostic information not possible from any other radiological modality. More invasive radiological procedures, such as myelography, may in many cases be obviated, especially if shorter segments of the vertebral column are to be surveyed. The CT findings in many cases are sufficiently characteristic to enable a specific diagnosis to be made.

The use of fine-needle percutaneous transhepatic cholangiography is becoming a standard procedure for investigating jaundiced patients undergoing surgery. The results of this procedure in 40 patients investigated at the Johannesburg Hospital show the importance of correlating the site of obstruction with the nature of the lesion.

We present a prospectus on the use of computer graphics for the three-dimensional reconstruction and visualization of brain lesions from computed tomographic head examinations, including an algorithm that utilizes surface contour information to reconstruct and display three-dimensional anatomical sites. We provide examples of the use of this algorithm. We offer an algorithm for estimation of the volume and surface area of anatomical sites. The advantages and disadvantages for the clinical use of these algorithms are discussed.

Two paraplegic men with post-traumatic syringohydromyelia presented initially with neuropathic arthropathy of the elbow and shoulder, respectively. Both patients had sustained spinal trauma years earlier and had been lost to orthopedic and neurosurgical follow-up study. Characteristic history and physical findings were present in both patients. Conventional myelography failed to demonstrate the lesion in the first patient. The diagnosis in the second patient was confirmed by lumbar injection of low-dose metrizamide followed by immediate and delayed computerized axial tomography in the supine and lateral positions. Both patients were treated by surgical decompression and subarachnoid shunts with arrest of the neurologic deterioration. To the authors' knowledge, this is the first report of patients with post-traumatic syringohydromyelia presenting with neuropathic joints. The present case reports illustrate the need for long-term follow-up studies of patients with spine injury in specialty clinics. The use of computerized axial tomography and low-dose intrathecal metrizamide is advocated for diagnosing post-traumatic syringohydromyelia.

A case of pneumatosis coli of the caecum and ascending colon with a closed loop obstruction secondary to carcinoma of the descending colon is presented. The caecum was grossly distended and impending rupture was diagnosed. It is postulated that complete transmural rupture of the caecum was prevented by partial decompression of caecal air into the bowel wall.