Evaluating Two Measures of Lumbar Spine MRI Overuse: Administrative Data Versus Chart Review.

PURPOSE: Lumbar spine (LS) MRI overuse may be identified in administrative data, but these data may lack the detailed clinical information needed to correctly assess overuse. The aim of this study was to compare chart review with analysis of administrative data to determine the appropriateness of LS MRI. METHODS: The sensitivity and specificity of the administrative method were determined, with inappropriateness regarded as the positive result, as if chart review determined the true state. Patients were the first 146 veterans who underwent LS MRI in the outpatient setting in fiscal year 2012 at the Veterans Affairs Palo Alto Health Care System. The InterQual criteria for chart review and the method of evaluating administrative data developed by CMS and endorsed by the National Quality Forum were used. Slight modifications were made to each measure to ensure completeness and comparability. RESULTS: Of the 146 scans reviewed, 23% were considered inappropriate by the administrative measure, whereas 59% were considered inappropriate by chart review. Compared with chart review, the administrative measure had specificity of 82% for identifying inappropriate scans and sensitivity of 27% for identifying appropriate scans. CONCLUSIONS: Compared with chart review, analysis of administrative data identified scans that were appropriate but underestimated inappropriate ordering. Contrary to expectations, chart review resulted in more scans being classified as inappropriate. The administrative method is economically feasible for identifying the overuse of LS MRI, but it underestimates the true extent of inappropriate ordering.

Content-based image retrieval in radiology: analysis of variability in human perception of similarity.

We aim to develop a better understanding of perception of similarity in focal computed tomography (CT) liver images to determine the feasibility of techniques for developing reference sets for training and validating content-based image retrieval systems. In an observer study, four radiologists and six nonradiologists assessed overall similarity and similarity in 5 image features in 136 pairs of focal CT liver lesions. We computed intra- and inter-reader agreements in these similarity ratings and viewed the distributions of the ratings. The readers' ratings of overall similarity and similarity in each feature primarily appeared to be bimodally distributed. Median Kappa scores for intra-reader agreement ranged from 0.57 to 0.86 in the five features and from 0.72 to 0.82 for overall similarity. Median Kappa scores for inter-reader agreement ranged from 0.24 to 0.58 in the five features and were 0.39 for overall similarity. There was no significant difference in agreement for radiologists and nonradiologists. Our results show that developing perceptual similarity reference standards is a complex task. Moderate to high inter-reader variability precludes ease of dividing up the workload of rating perceptual similarity among many readers, while low intra-reader variability may make it possible to acquire large volumes of data by asking readers to view image pairs over many sessions.

Portal vein thrombosis following laparoscopic sleeve gastrectomy for morbid obesity.

INTRODUCTION: Portal vein thrombosis has been documented after laparoscopic general surgery and has been uncommonly observed after laparoscopic bariatric surgery. Among bariatric operations, the sleeve gastrectomy is being performed with ever-increasing frequency. Here we report the case of a man who presented with portal vein thrombosis after laparoscopic sleeve gastrectomy. CASE DESCRIPTION: A 41-y-old man underwent an uneventful laparoscopic sleeve gastrectomy for the treatment of morbid obesity, and presented on postoperative day 10 with nonfocal abdominal pain, nausea, vomiting, and leukocytosis. Computed tomography revealed portal vein thrombosis, which was found in the setting of Clostridium difficile colitis. DISCUSSION: Portal vein thrombosis may be identified with increasing frequency as the number of laparoscopic bariatric operations continues to increase. A high index of suspicion is necessary to diagnose this rare, but potentially lethal, complication.

Using contrast-enhanced helical CT to visualize arterial extravasation after blunt abdominal trauma: incidence and organ distribution.

OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.