Trends in adverse events after IV administration of contrast media.

OBJECTIVE: Data collected from 1985 to 1999 on adverse events after the IV administration of contrast media were evaluated to identify trends. MATERIALS AND METHODS: Data collected on 391 adverse events after 90,473 administrations of iodinated contrast media and 19 events after 28,340 administrations of gadolinium were evaluated. Reactions were graded as mild, moderate, or severe. Data were also collected regarding contrast extravasation. RESULTS: When only ionic iodinated contrast material was used, the adverse reaction rate was 6-8%. With the selective use of contrast material, the adverse reaction rate was 0.6% and 0.7%, respectively, for ionic and nonionic agents. The rate decreased to 0.2% with the universal use of nonionic agents. More than 90% of adverse reactions were allergic-like. Seven severe reactions (0.05%) and no deaths occurred in the ionic group. During the selective use period, one death occurred in the nonionic group. No severe reactions or deaths occurred during the first 5 years of universal nonionic use. Since then, 10 severe reactions (0.02%) and one death have occurred. Seven reactions occurred in patients after helical CT angiography. The extravasation rate for iodinated contrast material has remained constant at 0.3-0.4% annually. The adverse reaction rate to gadolinium contrast material was 0.06%. CONCLUSION: Mild and moderate adverse events are more common with ionic contrast material than with nonionic. Most reactions are allergic-like. Severe reactions are seen equally with ionic and nonionic contrast material but differ in type. The reactions were allergic-like in the ionic group but were predominantly attributable to cardiopulmonary decompensation in the nonionic group. Helical CT angiography may play a role in reactions.

Meta-analysis of increases in micronuclei in peripheral blood lymphocytes after angiography or excretory urography.

Norman, A., Cochran, S. T. and Sayre, J. W. Meta-analysis of Increases in Micronuclei in Peripheral Blood Lymphocytes after Angiography or Excretory Urography. Radiat. Res. 155, 740-743 (2001). Meta-analysis of 10 studies confirms a significant increase in the frequency of micronuclei in peripheral blood lymphocytes after angiography or excretory urography; the weighted average increase is 4.2 (95% confidence interval 2.8-5.6) per 1000 binucleate lymphocytes, about the same increase in micronuclei as that produced in vitro by a diagnostic X-ray dose of 4 cGy. The analysis failed to reveal a significant effect of the specific contrast medium used in the X-ray examinations on the increased frequency of micronuclei. These results are consistent with the hypothesis that the effect of the contrast media is limited to the enhancement, by the photoelectric effect, of the X-ray dose absorbed by the lymphocytes irradiated while suspended in the contrast medium. Therefore, an estimate of increased cancer risk based on elevated frequencies of micronuclei or chromosome aberrations in peripheral blood lymphocytes may be greatly exaggerated whenever the radiation damage is largely confined to the cells circulating in the blood, as it is in people who have recently had X-ray examinations that use intravenous injections of contrast medium. Such examinations include angiography, excretory urography and CT scans, which are received annually by millions of people.

Cystic renal masses: accurate Bosniak classification requires adequate renal CT.

OBJECTIVE: The objective of this study was to assess the practical usefulness of the Bosniak classification system for separating surgical from nonsurgical cystic renal masses in a large number of patients examined with properly performed renal CT. The study included only patients whose scans were technically adequate to allow proper assignment of the lesion to a category. MATERIALS AND METHODS: The scans of 109 patients were gathered from two large teaching institutions both prospectively and retrospectively, yielding a total of 116 analyzable renal cystic lesions. Eighty-two masses were resected from 77 of these patients, retrospectively categorized by two experienced uroradiologists using the Bosniak classification system, and correlated with pathology reports. A second group of 34 lesions in 32 patients with atypical cysts was followed up prospectively for periods ranging from 3 months to 10 years. RESULTS: The results were similar for the two institutions: 15 resected categories I and II lesions were correctly identified as benign, and all 18 category IV lesions were malignant. Twenty-nine (59%) of 49 pooled category III masses were malignant. No malignancies have been identified in the prospectively monitored group of patients. CONCLUSION: Our results are compared with earlier, smaller series and support those that show that the Bosniak classification system is useful in separating lesions requiring surgery from those that can be safely followed up, provided proper CT techniques are used.

Complications of peritoneal dialysis: evaluation with CT peritoneography.

Computed tomographic (CT) peritoneography involves CT of the abdomen and pelvis after administration of a mixture of contrast material and dialysate. CT peritoneography can demonstrate a variety of complications of continuous ambulatory peritoneal dialysis. In patients with symptoms of peritonitis, CT peritoneography is better than conventional CT in demonstrating loculated fluid collections and indicates adhesions by means of uneven distribution of the contrast material-dialysate mixture. In patients with edema or abdominal bulging, CT peritoneography reliably shows the site of dialysate leakage and allows differentiation of a leak from a hernia. In patients with problems of fluid return, catheter malposition and its effect on dialysate distribution can be determined with CT peritoneography. In patients with poor ultrafiltration, demonstration of restricted space in the pelvis or poor distribution of fluid with CT peritoneography suggests adhesions. CT peritoneography also provides anatomic information for referring physicians that may determine whether treatment is medical or surgical.

Percutaneous nephrostomy: placement under CT and fluoroscopy guidance.

OBJECTIVE: The purpose of this paper is to present our experience with CT- and fluoroscopy-guided percutaneous nephrostomy tube (PNT) placement and to describe the technique of placement with patients in the supine-oblique position. MATERIALS AND METHODS: A CT scanner was coupled with a ceiling-mounted C-arm for fluoroscopy at the CT table, PNT was done with CT localization and fluoroscopic control. We attempted 148 placements in 129 patients, with most patients in the supine or the supine-oblique position. RESULTS: Successful PNT placement was achieved in 144 (97%) of 148 kidneys. In the native kidney group, 101 (81%) of 124 PNTs were placed with the patients in the supine-oblique position. We experienced no major complications, three (2%) minor complications, and two (1%) catheter dislodgments. CONCLUSION: CT-fluoroscopy control allows routine PNT placement with patients in the supine or the supine-oblique position and is associated with the lowest complication rate to our knowledge.

Helical CT angiography for examination of living renal donors.

OBJECTIVE: This prospective study was intended to determine if helical CT arteriography plus conventional radiography is sufficiently accurate to replace and less costly than excretory urography and conventional renal arteriography, the techniques currently used to examine living renal donors. SUBJECTS AND METHODS: Patients underwent CT arteriography with a helical CT scanner. Conventional radiographs were obtained during the pyelographic phase to evaluate the urothelium. Findings on CT arteriograms were compared with findings on conventional arteriograms and at surgery. RESULTS: Of 57 patients who underwent CT arteriography, 46 also underwent conventional arteriography and 40 underwent surgery. For those 46 patients, we found agreement between results of CT arteriography and conventional arteriography in 89% of kidneys. For those 40 patients, we found agreement between results of CT arteriography and findings at surgery in 90% of kidneys and agreement between results of conventional arteriography and findings at surgery in 87% of kidneys. Of the 57 patients, six (11%) had findings on CT angiograms that precluded further consideration for donation. CONCLUSION: Eight to ten percent of renal arteries are not seen on renal arteriograms when compared with findings at surgery. Our results indicate that CT arteriography is as accurate as conventional arteriography at revealing the number of vessels that perfuse and drain the kidneys and can replace conventional arteriography. Use of CT angiography plus conventional radiography instead of excretory urography and conventional arteriography can result in a 35-50% reduction in cost of the imaging studies in potential renal donors.

Renocolic fistulas: complementary roles of computed tomography and direct pyelography.

Three patients with renocolic fistulas are presented. Antegrade or retrograde pyelography showed the fistula in one patient but was unsuccessful in two others. CT demonstrated perinephric inflammation extending to the colon, complex air-fluid collections within the kidney, or extension of renal contrast into the colon. CT and direct pyelography complement each other for the diagnosis of renocolic fistulas.

Quality assessment and improvement: what radiologists do and think.

OBJECTIVE: The main objectives of the study were as follows: first to study the nature and extent of radiologists' involvement in and their attitudes toward quality assessment (QA) and continuous quality improvement (CQI)/total quality management (TQM) in hospitals and in offices; and second, to ascertain whether differences in size, type, and location among hospitals and nonhospital radiology offices affect the QA and CQI/TQM activities of radiologists. We analyzed data from a national survey conducted by the American College of Radiology (ACR) in 1993. MATERIALS AND METHODS: Questionnaires about QA and CQI/TQM activities and attitudes were mailed to 216 hospital-affiliated diagnostic radiology group practices using a sample selected from the ACR master list of radiology practices in the United States. The response rate was 90%. A stratified random sample ensured representation of different geographic regions, various group sizes, and both academic and nonacademic groups. Responses were weighted so that our data show what answers about hospitals would have been if (i) the survey had been answered by all hospital radiology departments in the United States (except for those few staffed by solo practitioners or nonradiologists) and (ii) our questions about nonhospital offices had been answered by all radiology groups in the United States (except those few having no hospital activity). RESULTS: The majority (86%) of hospital radiology departments report having a program to monitor and evaluate physicians' performances. Fifty-one percent collect incorrect diagnoses by specific radiologist. Twenty-eight percent collect some of their QA data through computerized information systems. We found some statistically significant differences by hospital size and location, with larger hospitals and urban hospitals being more likely to engage in some QA activities. Multivariate analyses, once controlled for hospital size and location, found no significant differences in QA activity between university and community hospitals or between hospitals with and without a residency program. QA and CQI programs were less common in offices than in hospitals. With the exception of mammographic interpretations, most practices did not monitor and evaluate physicians' performances in the office setting. Respondents representing 58% of hospital radiology departments thought that QA and CQI contributed to improvement in patient care. Only 19% of radiology practices answered that CQI has been of cost benefit to their organization. CONCLUSION: Most radiology practices engage in a variety of QA and CQI activities in hospitals. However, this is less true in offices, in which radiologists have more discretion, and radiologists remain skeptical about the usefulness of CQI.

Induction of micronuclei in lymphocytes of patients undergoing excretory urography with ioversol.

RATIONALE AND OBJECTIVES: The hypothesis that nonionic contrast medium administered during excretory urography may cause cytogenetic damage was tested. METHODS: Micronuclei were scored in peripheral blood lymphocytes obtained from 33 patients before and after excretory urography with ioversol, a nonionic contrast medium. RESULTS: The examination resulted in a highly significant (sign test, P = .005) increase in the median (range) counts of micronuclei per 1,000 binucleate from 18 (0 to 31) before to 24 (5 to 40) after excretory urography. CONCLUSIONS: Nonionic ioversol produces a statistically significant increase in the chromosome damage of lymphocytes from patients undergoing excretory urography. This increase is similar to that reported for the ionic contrast media, ioxaglate and iothalamate, and equal to that produced by 6 to 7 cGy of 100-kilovolt x-rays.

Noninvasive radiological diagnosis of renal vein thrombosis in renal transplantation.

Thrombosis of the allograft renal vein is a rare complication of renal transplantation. Of 557 consecutive renal transplants performed between January 1, 1985 and November 30, 1989, 3 cases occurred for an over-all incidence of 0.4%. In 2 cases the diagnosis was made preoperatively with renal scintigraphy and duplex Doppler sonography. No graft was salvaged, despite timely diagnosis in 2 patients. We conclude that the diagnosis of renal vein thrombosis in the renal allograft recipient should be suspected clinically and by the radiographic findings of absent perfusion on renal scintigraphy, and the detection of an arterial signal, albeit abnormal, on duplex Doppler sonography. When diagnosed, nephrectomy appears to be the only treatment.

Percutaneous nephrostomy tube placement: an outpatient procedure?

The authors report their experience with 56 percutaneous nephrostomies (PCNs) performed on an outpatient basis on 55 patients. Complications included pain that required use of parenteral medication in four patients, bleeding in three that resolved spontaneously, and shaking chills or fever in 12. This last complication, considered to be a sign of sepsis and treated with antibiotics, occurred more frequently than the 1.4%-4.5% infectious complication rate reported in the literature. Antibiotic use during and after PCN significantly decreased the likelihood of sepsis. In the high-risk group, antibiotic administration during and after PCN decreased the risk of developing signs of sepsis from 50% to 9%. On the basis of the authors' results and the findings in the literature about antibiotic prophylaxis, guidelines are recommended to improve the safety of PCN as an outpatient procedure. In the majority of instances PCN should still be considered to be more safely performed as an inpatient procedure at this time.