Comparison of patient comfort between iodixanol and iopamidol in contrast-enhanced computed tomography of the abdomen and pelvis: a randomized trial.

BACKGROUND: Previous clinical studies have shown that iso-osmolar iodixanol (Visipaque®) causes less patient discomfort than low-osmolar contrast media (LOCM) when administered via intra-arterial injection. No data are available comparing these agents for patient discomfort when administered intravenously (i.v.) using power injectors. PURPOSE: To compare the frequency and intensity of patient discomfort between iodixanol and iopamidol (Isovue®) administered i.v. using a power injector in contrast-enhanced computed tomography (CECT) of the abdomen and pelvis. MATERIAL AND METHODS: This was a prospective, randomized, double-blind, multicenter study of iodixanol 320 mg I/mL or iopamidol 370 mg I/mL on patient discomfort. The presence of discomfort (heat, pain, coldness) and intensity was verbally rated by patients on a 0-10 scale and converted into four categories (0, none; 1-3, mild; 4-7, moderate; 8-10, severe). Image quality was evaluated. RESULTS: Of the 299 evaluable patients enrolled at nine centers, 151 received iodixanol and 148 received iopamidol. The average age was 58 years. Iodixanol patients experienced significantly less moderate/severe discomfort (35.1% vs. 67.3%; P < 0.0001) or heat (29.8% vs. 63.9%; P < 0.0001), and severe discomfort (2.6% vs. 16.3%; P = 0.0004) or heat (2.6% vs. 15%; P = 0.0008), but three times more no discomfort (21.2% vs. 7.5%; P = 0.0008) than iopamidol patients. Excellent image quality was in 95.4% of iodixanol vs. 89.9% of iopamidol patients (P = 0.0508). Overall, adverse event (AE) rate excluding patient discomfort was 19.9% in the iodixanol group and 14.9% in the iopamidol group (P = 0.2870), but contrast-related AEs were comparable: 11.3% vs. 10.1% (P = 0.8522). Delayed skin reactions occurred in 2.6% of patients in the iodixanol group and in no patient in the iopamidol group (P = 0.1226). CONCLUSION: Patients receiving iodixanol had significantly lower moderate-to-severe or severe discomfort than patients receiving iopamidol, with heat being the major contributor. Iodixanol use trended towards better image quality but the difference was not statistically significant. No significant differences in incidences of overall or contrast-related AEs or delayed skin reactions were seen between the two groups. These data support that CM osmolality may be a key determinant of patient discomfort.

Rapid diagnosis of pedal osteomyelitis in diabetics with a technetium-99m-labeled monoclonal antigranulocyte antibody.

An in vivo method of labeling white cells that diagnoses diabetic pedal osteomyelitis safely, rapidly, and accurately is desirable. The objectives of this investigation were to evaluate a technetium-99m-labeled monoclonal antigranulocyte antibody for diagnosing diabetic pedal osteomyelitis, compared with indium-111-labeled leukocyte and 3-phase bone imaging for this purpose. Twenty-five diabetic patients with pedal ulcers, 22 in the forefoot and 3 in the midfoot, underwent antibody, indium-111-labeled leukocyte, and technetium-99m methylene diphosphonate 3-phase bone imaging. The 1-hour antibody, 24-hour labeled leukocyte, and 3-phase bone images were interpreted separately for the presence of osteomyelitis. The antibody and labeled leukocyte images also were interpreted together with the bone images to determine if the combined study was more accurate than each individual study. There were 10 cases of osteomyelitis among the 25 patients. The sensitivity, specificity, and accuracy of the antibody were.90,.67, and.76, respectively. These results were not significantly different from those obtained with labeled leukocyte imaging:.80,.67, and.72, respectively. The antibody was significantly more specific (P =.004) than 3-phase bone imaging (.27). Interpreting the antibody together with the bone scan did not alter the results. When interpreted with the bone images, the accuracy of labeled leukocyte imaging improved from.72 to.80. This was not significantly more accurate than either the antibody or labeled leukocyte imaging alone. The data suggest that the monoclonal antigranulocyte antibody is comparable with in vitro labeled leukocyte imaging for diagnosing pedal osteomyelitis in diabetic patients, and warrants further investigation in a larger population.

Osteomyelitis: diagnosis with (99m)Tc-labeled antigranulocyte antibodies compared with diagnosis with (111)In-labeled leukocytes--initial experience.

PURPOSE: To compare a technetium 99m-labeled murine immunoglobulin M monoclonal antigranulocyte antibody that binds to human polymorphonuclear leukocyte CD15 antigens with indium 111 ((111)In)-labeled leukocytes in the diagnosis of appendicular skeletal osteomyelitis. MATERIALS AND METHODS: Twenty-four patients suspected of having infected joint replacement (n = 12), diabetic pedal osteomyelitis (n = 8), or long bone osteomyelitis (n = 4) were imaged 5, 30, 60, and 120 minutes after antibody injection. Following injection, one patient experienced moderate joint pain exacerbation that resolved spontaneously. Patients underwent imaging with (111)In-labeled leukocytes and three-phase bone imaging. All studies were interpreted alone. Images obtained in antibody and (111)In-labeled leukocyte studies were also interpreted with the bone scans. One reader, without knowledge of other study results or final diagnoses, reviewed and interpreted images in a random order. Sensitivity, specificity, and accuracy were calculated for the antibody study at each time point, the (111)In-labeled leukocyte study, the three-phase bone scanning procedure, and dual-tracer studies. RESULTS: There were 11 cases of osteomyelitis. Bone scintigraphy was sensitive (1.0) but nonspecific (0.38). Images obtained in the 120-minute antibody study were sensitive (0.91), moderately specific (0.69), and comparable to those obtained in the (111)In-labeled leukocyte study (0.91 sensitivity, 0.62 specificity). When interpreted with bone scans, images obtained in the antibody and (111)In-labeled leukocyte studies showed improved sensitivity and specificity (1.0 and 0.85 and 1.0 and 0.77, respectively). CONCLUSION: Use of the monoclonal antigranulocyte antibody was comparable to the use of (111)In-labeled leukocytes in the diagnosis of appendicular skeletal osteomyelitis. The combined results of the monoclonal antibody study and bone scanning were more accurate (0.91) for diagnosing this entity than were the results of any of the other studies.