Dextran microsphere embolization: experimental and clinical experience with radiologic-pathologic correlation. Work in progress

The radiologic and pathologic effects of canine renal embolization with dextran microspheres of two size ranges (40-150 micron and 100-300 micron) were studied 30 minutes and 1, 2, 4, and 6 weeks after embolization. Dramatic occlusions occurred with very small quantities of these particles, which reached more distally and were suspended and embolized more easily than other solid embolic agents. Because of these qualities, however, they should be used with more caution. They can be injected through 2-F catheters, calibrated-leak balloons, and open-ended guide wires. Embolization with dextran microspheres was also used for epistaxis, meningioma, dural arteriovenous malformation, renal tumors, bone metastasis, multiple myeloma, or peripheral angioma in ten patients. The technique was safe and effective, but special attention should be directed to proper dilution and gentle embolization with careful monitoring to avoid excessive embolization or reflux.     

Peritoneal reaction resulting from iodinated contrast material: comparative study

A consensus does not exist as to the optimal contrast agent for hysterosalpingography. This study was undertaken to evaluate the early and delayed inflammatory responses of the peritoneal surfaces to various types of iodinated contrast media. Guinea pigs received intraperitoneal injections of lactated Ringer solution, iothalamate meglumine, diatrizoate sodium, ioxilan, or ethiodized oil. The inflammatory response of the peritoneal surfaces was assessed at 1,7, and 30 days. Five animals were studied at each time point for each agent. No animals that received Ringer lactate or iothalamate meglumine had inflammation at any time. Ioxilan produced inflammation in two of five animals at 7 days and no inflammation at 1 or 30 days. Ethiodized oil produced no inflammation at 1 day; however, three animals had inflammation at 7 days, and all five had inflammation at 30 days. The 30-day group showed striking inflammatory response with granulomatous features. The authors recommend the continued use of meglumine-based water-soluble ionic contrast material for hysterosalpingography.     

Human leg neuromuscular diseases: P-31 MR spectroscopy

Phosphorus-31 magnetic resonance (MR) spectra of leg muscles in patients with the neuromuscular diseases Duchenne dystrophy, myotonic dystrophy, postpoliomyelitis, Werdnig-Hoffmann disease, and pedal dystonia were recorded. Ratios of beta-adenosine triphosphate (ATP), inorganic phosphate (Pi), alpha-glycerophosphorylcholine (GPC), and phosphomonoesters to phosphocreatine (PCr) were calculated from peak integrals and compared with normal muscle ratios. In all diseases studied, beta-ATP/PCr and Pi/PCr values showed an increase from normal values. The extent of increase in beta-ATP/PCr was related to the clinical severity of the disease, suggesting that this could be a useful noninvasive means of monitoring effectiveness of therapy for neuromuscular disorders. In myotonic dystrophy and Werdnig-Hoffmann disease, GPC/PCr values increased greatly. The intracellular pH in Duchenne and postpoliomyelitis muscles was slightly elevated compared with that in normal muscles. Hydrogen-1 MR images of muscles showed fat infiltration in all patients, more in weaker muscles and less in stronger muscles.     

Simon nitinol inferior vena cava filter: initial clinical experience. Work in progress

The Simon nitinol filter for percutaneous interruption of the vena cava to prevent pulmonary embolism is currently undergoing a multicenter clinical trial. Preliminary clinical results are reported as work in progress. The results in 44 patients at two centers are analyzed in detail, and major events are reported from 103 patients in 17 centers in the United States during a 10-month period. The filter was successfully inserted via the femoral or jugular route in all patients through a 9-F catheter. The placement procedure was easy and without significant complications. Follow-up studies included plain radiography, ultrasonography, magnetic resonance (MR) imaging, and clinical evaluation. No filter migration or perforation occurred among the 103 patients. Symptomatic occlusions occurred in 7%-9%, comparable to other series, and some asymptomatic occlusions were detected with MR imaging only. The implications of occlusion of the filter are discussed.