Low-keV and Low-kVp CT for Positive Oral Contrast Media in Patients with Cancer: A Randomized Clinical Trial.

Background Substantial gain in the attenuation of iodine on low-kVp and dual-energy CT processed low-keV virtual monochromatic images provides an opportunity for customization of positive oral contrast media administration. Purpose To perform an intrapatient comparison of bowel labeling, opacification, and taste preference with iodinated oral contrast medium (ICM) in standard (sICM) and 25%-reduced (rICM) concentrations at low tube voltage (100 kVp) or on low-energy (50-70 keV) virtual monochromatic images compared with barium-based oral contrast medium (BCM) at 120 kVp. Materials and Methods In this prospective clinical trial, 200 adults (97 men, 103 women; mean age, 63 years ± 13 [standard deviation]) who weighed less than 113 kg and who were undergoing oncologic surveillance (from April 2017 to July 2018) and who had previously undergone 120-kVp abdominopelvic CT with BCM randomly received sICM (7.2 g iodine) or rICM (5.4 g iodine) and underwent 100-kVp CT or dual-energy CT (80/140 kVp) scans to be in one of four groups (n = 50 each): sICM/100 kVp, rICM/100 kVp, sICM/dual-energy CT, and rICM/dual-energy CT. Qualitative analysis was performed for image quality (with a five-point scale), extent of bowel labeling, and homogeneity of opacification (with a four-point scale). Intraluminal attenuation of opacified small bowel was measured. A post-CT patient survey was performed to indicate contrast medium preference, taste of ICM (with a five-point scale), and adverse effects. Data were analyzed with analogs of analysis of variance. Results All CT studies were of diagnostic image quality (3.4 ± 0.3), with no difference in the degree of bowel opacification between sICM and rICM (P > .05). Compared with BCM/120 kVp (282 HU ± 73), mean attenuation was 78% higher with sICM/100 kVp (459 HU ± 282) and 26%-121% higher at sICM/50-65 keV (50 keV = 626 HU ± 285; 65 keV = 356 HU ± 171). With rICM, attenuation was 46% higher for 100 kVp (385 HU ± 215) and 19%-108% higher for 50-65 keV (50 keV = 567 HU ± 270; 65 keV = 325 HU ± 156) compared with BCM (P < .05). A total of 171 of 200 study participants preferred ICM to BCM, with no taste differences between sICM and rICM (3.9 ± 0.6). Fifteen participants had diarrhea with BCM, but none had diarrhea with ICM. Conclusion A 25%-reduced concentration of iodinated oral contrast medium resulted in acceptable bowel labeling while yielding substantially higher luminal attenuation at low-kVp and low-keV CT examinations with improved preference in patients undergoing treatment for cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Laghi in this issue.

Zinc and selenium modulate barium-induced oxidative stress, cellular injury and membrane-bound ATPase in the cerebellum of adult rats and their offspring during late pregnancy and early postnatal periods.

CONTEXT: Barium (Ba) may induce oxidative stress leading to tissues injury. OBJECTIVE: Our study investigated the therapeutic efficiency of zinc (Zn) and selenium (Se) against neurotoxicity induced by Ba in adult rats and their progeny. MATERIAL AND METHODS: Pregnant rats are exposed either to Ba (67 ppm), Ba + Zn, Ba + S or to only Zn and Se. RESULTS: In Ba-treated rats, there was an increase of MDA, H2O2, AOPP levels and SOD activity in the cerebellum of dams and their pups, a decrease in GPx, CAT, AChE, Na+K+-ATPase and Mg2+-ATPase activities, GSH and NPSH levels. These changes were confirmed by histological damages. Co-administration of Zn or Se to Ba-treated rats ameliorated the biochemical and histological aspects. CONCLUSION: Our results revealed that Zn and Se have shown promising effects against Ba toxicity in the cerebellum of adult rats and their suckling pups.

Colon ischaemia secondary to barolith obstruction.

A case is described of an elderly woman who developed an obstructing barolith in the sigmoid colon following a barium enema. Colonic ischaemia developed in the proximal colon. Predispositions and prevention of baroliths are discussed.

Anaphylaxis to carrageenan: a pseudo-latex allergy.

BACKGROUND: Anaphylactic reactions during a barium enema have been attributed to allergy to latex on the barium enema device. The observation of anaphylaxis during barium enema without latex exposure or latex allergy led to the performance of an allergy skin test to the barium enema solution. METHODS: Individual components of the barium enema solution were obtained for double-blind skin testing. A RAST to identify specific IgE antibodies to the skin test active agent was established. RESULTS: Carrageenan, a component of the barium enema solution, produced positive reactions to allergy skin test and RAST. Gastrointestinal symptoms for which the patient was being investigated by the barium enema subsequently disappeared with a diet free of carrageenan. CONCLUSIONS: Carrageenan is a previously unreported cause of anaphylaxis during barium enema. It is an allergen widely distributed in common foods and potentially could account for some symptoms related to milk products or baby formula.

A review of environmental characteristics and health effects of barium in public water supplies.

A comprehensive review is made of sources, occurrence, removal, health effects and water quality standard of barium in public drinking water supplies. The primary source of naturally occurring barium in drinking water results from the leaching and eroding of this metal from sedimentary rocks into the aquifers of ground water. It is a localized problem in several areas of the United States. The removal of barium from drinking water appears to be most efficiently accomplished utilizing ion exchange softening. Health effects studies are based primarily on animal experimentation. Such effects include stimulation of smooth, striated, and cardiac muscle, elevation of blood pressure, initiation of catecholamine release, rapid and preferential deposition in bone, and excretion principally in the feces. Humans over 60 years of age appear to be at high risk to developing cardiac arrhythmias following the barium enema. The current United States drinking water standard of 1.0 mg/l is based on several faulty assumptions and should be critically reevaluated.