Infection versus tumor in the spine: criteria for distinction with CT

To develop criteria to distinguish among pyogenic infection, nonpyogenic infection, and neoplastic processes in the spine by means of computed tomography (CT), the authors retrospectively analyzed 17 cases of pyogenic infection (20 sites), 40 cases of neoplastic disease (56 sites), and five cases of granulomatous infection (eight sites). Reliable criteria for pyogenic infection were complete prevertebral soft-tissue involvement, diffuse osteolytic destruction, gas within both bone and soft tissue, and a process centering on an intervertebral disk. Neoplastic disease was characterized by posterior element involvement, partial or absent prevertebral soft-tissue swelling, and osteoblastic alterations. In a limited number of cases, nonpyogenic infection was characterized by focal lytic bone involvement and marginal sclerosis. Blinded testing of these criteria indicated potential for improved diagnostic accuracy in clinical practice.     

Unsatisfactory hepatic perfusion after placement of an implanted pump and catheter system: angiographic correlation

Thirty-five patients with scintigrams showing unsatisfactory hepatic artery perfusion after surgical placement of an implanted pump and catheter system were examined with selective angiography (33 cases) or digital subtraction angiography (DSA) during which the contrast material was injected through the side port of the pump (six cases). In 34 of 35 cases, the cause of the unsatisfactory (either extrahepatic or incomplete) hepatic perfusion was defined. DSA was definitive in only two cases, in which extrahepatic flow through collateral vessels was demonstrated. The cause of the perfusion defect was hepatic artery thrombosis in 14 cases, extrahepatic flow through collateral vessels in 14 cases, a misplaced catheter in four cases, and a short proper hepatic artery without adequate length for mixing in two cases. Although hepatic artery perfusion scintigraphy is the primary tool for evaluation of hepatic perfusion after catheter placement, angiography plays an important role in treating the subset of patients with unsatisfactory hepatic perfusion.     

Association of heterotopic gray matter with seizures: MR imaging. Work in progress

Heterotopic gray matter, which previously had been associated with severe congenital malformations of the brain and developmental delay, was found without these associated conditions. The authors found ten cases of heterotopic gray matter on magnetic resonance (MR) images. The lesions had a signal intensity that was isointense compared with that of gray matter on T1, spin-density, and T2-weighted images. Nine of the ten cases were associated with a seizure disorder. The tenth case, discovered during a workup for metastatic lung disease, was confirmed with pathologic studies. Heterotopic gray matter is the presence of cortical neurons in an abnormal location, which may be periventricular (nodular) or within the white matter (laminar). A knowledge of heterotopic gray matter and its association with seizures may prevent the misinterpretation of findings on MR images.     

Follow-up of 13 children after ureterosigmoidostomy

Follow-up of 13 children who had had a ureterosigmoid anastomosis 3 1/2 to 10 years previously and whose initial urogram had been satisfactory, showed that growth was normal and that there was no serious metabolic disorder. In particular whole-body potassium did not differ significantly from normal values (as given by Langham, 1961). Asymptomatic urinary infection is the chief hazard in these cases but is difficult to diagnose and may lead to progressive dilatation of the ureters.