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We describe a diagnostically challenging case of infection due to a species of Salmonella in a ventricular aneurysm. Two-dimensional transthoracic echocardiography, gallium 67 scanning, and cardiac gated magnetic resonance imaging were required to make the diagnosis. Antimicrobial therapy alone was insufficient and included intravenously administered ciprofloxacin, which has been reported to be effective in refractory cases of salmonella bacteremia. The diagnosis was confirmed at surgery, which was required to achieve clinical cure. Among six previously reported cases, only one individual survived.

Acute perforated appendicitis due to large numbers of inspissated lead shot occurred in two inuit who hunted and ate game regularly. Both lived in remote villages distant from a hospital.

We investigated in vitro NMR properties of bleomycin-induced alveolitis and pulmonary fibrosis in 18 Lewis rats (6 controls). When alveolitis or fibrosis had developed, animal lungs were excised and examined histologically and gravimetrically and their T1 and T2 were determined by a NMR spectrometer at 10.7 MHz and 37 degrees C. Clinical diagnosis was confirmed histologically in each case. The NMR signal intensities were significantly elevated in both disease states (P less than 0.001). Both T1 and T2 values of alveolitic lungs were about the same as in controls, but were significantly decreased in fibrotic lungs (P less than 0.01). Changes in T1 and T2 correlated well (P less than 0.001) with changes in water content of diseased lungs.

The classical features of regional enteritis--a thickened edematous mesentery and edema of the submucosa--have been demonstrated by computed tomography. Future experience may confirm its value in separating inflammatory and neoplastic diseases of the small bowel.

Neurological, CT and high-field (1.5T) magnetic resonance imaging (MRI) data were correlated in 6 patients previously clinically diagnosed as having suffered small vertebrobasilar infarct. MRI demonstrated infarcts in areas where CT was nearly always negative. MRI allowed very precise clinico-topographic correlations and appears to be the preferred imaging technique in vertebrobasilar infarcts.

Access to medical services in north Canada is limited by geography, climate, communication and transportation. A geostationary spacecraft, Hermes, was used to provide dependable, high-quality communication between a remote nursing station, a base hospital and a health science centre. Teleradiology formed an important component of the telemedicine services. Remote supervision of radiography and fluoroscopy was made possible; consultation services were shown to be 90% effective.

A review of 15 months' experience shows the major indications for sagittal and coronal reconstruction images in computed body tomography (CBT) are in the differentiation of lung disease from disease of the chest wall; of supradiaphragmatic from infradiaphragmatic lesions; of intrahepatic from perihepatic abnormality; of renal from perirenal disease; in establishing the level of obstruction in the jaundiced patient and in mapping pelvic malignancy. The accurate definition of the extent of disease proved beneficial in planning further diagnostic procedures (needle aspiration for malignant cells or abscess drainage), in determining the surgical approach, and in planning radiation therapy.

Three patients with focal brain-stem oculomotor disturbances (nuclear sixth nerve syndrome, sixth nerve palsy, bilateral internuclear ophthalmoplegia) as a consequence of multiple sclerosis have been studied with high-volume delayed computed tomography and high-field magnetic resonance imaging. In all of them, high-volume delayed computed tomography was inconclusive in the brain stem, but magnetic resonance imaging showed an area of prolonged T1 and/or T2 in the region appropriate to the oculomotor findings. Magnetic resonance imaging is the imaging technique of choice of small plaques in the brain stem. It can considerably aid clinicotopographic correlation in multiple sclerosis.

Pulmonary edema was produced in four anesthetized dogs by saline lavage. The animals were maintained by assisted ventilation with O2/halothane and examined by a nuclear magnetic resonance (NMR) 0.15T resistive-magnet imager. The distribution of edematous fluid was clearly observed. Image contrast increased with prolongation of the cycle time (TR). Tomographic maps of spin-lattice relaxation times (T1) of the lungs were calculated from the NMR images. Comparison of T1 values with gravimetric measurements of water content of lung samples showed significant correlation (r = .7, P less than .02, n = 12) suggesting a potential for in vivo lung water quantitation by NMR imaging. This in vivo correlation is qualitatively similar to the in vitro correlation. Accurate in vivo determinations of pulmonary T2 values may require respiratory gating.

A total digital teleradiology system using a prototype DuPont laser beam scanner (DTR 2000) and a Bell Canada digital transmission network was evaluated. A total of 489 radiographic and ultrasonographic examinations were transmitted for interpretation from a 41-bed rural community hospital in Seaforth to the University Hospital in London, Ontario, 80 km away. There was concurrence in 98% of these examinations, i.e. the laser-sensitive facsimile film clearly duplicated the original film findings and allowed a confident interpretation to be made. We conclude that this system could readily serve the needs of family physicians in rural communities for radiologic consultation, diagnosis, management, and triage of patients 24 hours per day.

Present technologic limitations do not allow completely accurate reproduction of a chest film, the gold standard of teleradiology. Although interpretation accuracy of broad-band teleradiographs is reasonably good and encouraging, the low level of confidence engendered by teleradiology interpretations in narrow-band transmission is self-evident in view of the tendency to provide an immediate provisional report followed later by a signed report after direct viewing of the film. Despite this, the important observation, putting things into perspective, was made by Andrus and Bird, namely that "the question is not whether teleradiology is preferable to direct visualization when either is available, but whether teleradiology offers an acceptable universally applicable method to augment the usefulness of the radiologist." Although fiberoptic guides may well lace the country in a few years, providing ample capacity and superb transmitted images, there are several options presently worth investigating now. These could provide teleradiology services to remote and rural communities, depending on the level of need and skills at the remote site, the availability and cost of transmission, and the need for access to 24-hour consultation services. The future role of teleradiology on a much larger scale within a regional network of health care facilities has yet to be defined, based on the perceived need for reasonable access to expensive but precise imaging methods. On the face of it, it would seem unlikely that small community hospitals will be able to afford the cost and maintenance of CT and MR scanners, digital angiography, and other useful and accepted imaging services.(ABSTRACT TRUNCATED AT 250 WORDS)

To determine whether or not hepatic computed tomography density is an alternative to liver biopsy for the diagnosis of body iron overload, hepatic computed tomography density was determined in healthy controls, patients with idiopathic hemochromatosis, and patients with liver disease. Hepatic computed tomography density was obtained from a single computed tomography slice taken through the liver on a General Electric CT/T 8800 scanner. In 69 controls, hepatic computed tomography density ranged from 11 to 36 units (mean = 30). Given an upper limit of normal of 36 computed tomography units, 4 of 6 untreated patients with idiopathic hemochromatosis had elevated hepatic computed tomography density compared with 0 of 8 patients after venesection (X2 = 7.5, p = 0.01). Hepatic computed tomography density correlated directly with serum ferritin (r = 0.72, p = 0.01). In 58 consecutive patients with clinical or biochemical evidence, or both, of liver disease who underwent liver biopsy for diagnostic purposes, 0 of 52 patients with normal hepatic iron had an elevated hepatic computed tomography density as compared with 4 of 6 patients with excess iron (X2 = 35, p less than 0.001). An elevated hepatic computed tomography density associated with an elevated serum ferritin indicates iron overload; however, a normal hepatic computed tomography density does not exclude iron overload. When computerized tomography is applied to patients with an unexplained elevation of the serum ferritin, it provides a noninvasive alternative to liver biopsy for the detection of excess hepatocellular iron.

Small infarctions of the medulla produce typical neurologic deficits and can be clinically recognized fairly reliably. High-field magnetic resonance imaging with a 1.5 T prototype scanner successfully demonstrated very tiny medulla infarctions in three of five patients. These lesions were imaged readily by a fairly rapid (approximately 1-2 min scan time) partial-saturation technique and confirmed on multiple spin-echo images. In addition, in two cases vertebral occlusion ipsilateral to the infarction was suggested by high signal on T2 weighted spin-echo images.