CT enterography: technical and interpretive pitfalls.

CT enterography is a first-line test at many institutions to investigate potential small bowel disorders. While numerous articles have focused on the ability of CT enterography to diagnose and stage Crohn's disease, small bowel neoplasia, and malabsorptive or vascular disorders, this article reviews CT enterography limitations, technical and interpretive pitfalls, image review tactics, and complementary radiologic and endoscopic examinations to improve diagnostic accuracy. CT enterography limitations include its inability to demonstrate isolated mucosal abnormalities such as aphthous ulcers and its use of ionizing radiation. The most common technical pitfall of CT enterography is inadequate small bowel distention resulting from inadequate ingestion, gastric retention, or rapid small bowel transit of a large volume of neutral enteric contrast material. Additionally, segments of jejunum are frequently collapsed. Interpretive pitfalls commonly result from peristaltic contractions, transient intussusception and opaque intraluminal debris. Opaque debris is especially problematic during multiphasic CT enterography performed to identify potential small bowel sources of obscure gastrointestinal bleeding. False-negative examinations may result from inadequate radiation dose. Examinations complementary to CT enterography include small bowel follow through, enteroclysis, CT enteroclysis, MR enterography, MR enteroclysis, capsule endoscopy, and balloon-assisted endoscopy. Properly performed and accurately interpreted CT enterography contributes to the diagnosis and management of small bowel disease by itself and as a complement to other radiologic and optical small bowel imaging examinations.

Ultrasound and fine-needle aspiration in dermatology, underuse of minimally invasive, efficient diagnostic tools.

BACKGROUND: Ultrasound imaging and ultrasound-guided fine-needle aspiration (FNA) are common procedures used to evaluate and sample cutaneous and subcutaneous tissue. Although ultrasound and FNA have been explored for individual neoplasms, lymph node involvement, and metastases, their use in day-to-day dermatology is not well defined. OBJECTIVE: To investigate the use and utility of ultrasound and FNA in the dermatologic surgery division of a large academic institution. METHODS: Retrospective case review of all ultrasound and FNA procedures ordered by a dermatologic surgeon over a 3-year period. RESULTS: Metastatic disease was suspected in 11 of 21 (52.4%) cases. Cytology confirmed the presence of metastatic disease in two of the 11 cases, and metastatic disease was identified in one additional case in which the diagnosis was not suspected at clinical presentation. Cytology revealed leukemia or lymphoma in three (14.3%) cases, two of which were new diagnoses. Sonographic imaging and cytology revealed a benign diagnosis in 16 (76.2%) cases, five of which were reactive lymph nodes. CONCLUSIONS: The results suggest that ultrasound and FNA are underused techniques that may play an important role in dermatology diagnostics and have the potential for expansion in day-to-day clinical practice.

Automatic selection of tube potential for radiation dose reduction in vascular and contrast-enhanced abdominopelvic CT.

OBJECTIVE: The purpose of this study is to assess the ability of a novel automatic tube potential selection tool to reduce radiation dose while maintaining diagnostic quality in CT angiography (CTA) and contrast-enhanced abdominopelvic CT. MATERIALS AND METHODS: One hundred one CTA examinations and 90 contrastenhanced abdominopelvic examinations were performed using an automatic tube potential selection tool on a 128-MDCT scanner. Two vascular radiologists and two abdominal radiologists evaluated the image quality for sharpness, noise, artifact, and diagnostic confidence. In a subset of patients who had undergone prior studies (CTA, 28 patients; abdominopelvic CT, 25 patients), a side-by-side comparison was performed by a separate radiologist. Dose reduction and iodine contrast-to-noise ratio resulting from use of the tool were calculated. RESULTS: For CTA, 80 or 100 kV was selected for 73% of the scans, with a mean dose reduction of 36% relative to the reference 120-kV protocol. For abdominopelvic CT examinations, 80 or 100 kV was used for 55% of the scans, with a mean dose reduction of 25%. Overall dose reduction relative to the reference 120-kV protocol was 25% and 13% for CTA and abdominopelvic CT scans, respectively. Over 98% of scans had acceptable sharpness, noise texture, artifact, and diagnostic confidence for both readers and diagnostic tasks; 94-100% of scans had acceptable noise. Iodine contrast-to-noise ratio was significantly higher than (p < 0.001) or similar to (p = 0.11) that of prior scans, and equivalent quality was achieved despite the dose reduction. CONCLUSION: Automatic tube potential selection provides an efficient and quantitativeway to guide the selection of the optimal tube potential for CTA and abdominopelvic CT examinations.

Detection of distal ureteral stones in pregnancy using transvaginal ultrasound.

AIMS: To determine the performance of transvaginal ultrasound for the visualization of distal ureteral stones in pregnant patients with renal colic and to evaluate the diagnostic value of secondary findings suggestive of obstructing ureteral stone disease. METHODS: We retrospectively identified 129 pregnant patients with a total of 142 encounters with both abdominal and transvaginal ultrasound. Ultrasound images for each patient were reviewed recording the presence of stone with location, hydronephrosis, resistive indices (RI), and status of the ureteral jets. Patients were subcategorized into two groups based on the visualization of distal ureteral stone. RESULTS: The transvaginal technique identified 94% (N = 16/17) of sonographically detected stones in the distal ureter/urethra, while the transabdominal technique identified 29% (N = 5/17). The combined imaging for initial assessment of renal colic in pregnancy demonstrated a sensitivity of 89%, specificity 100%, and negative predictive value (NPV) of 98%. The frequency of hydronephrosis was statistically greater in the visualized stone group (94% vs 51%). Mean RI was identical in both groups however the delta RI was significantly elevated in those patients with distal ureteral stones with a mean delta RI value of 0.05. The rate of absence of ureteral jets was not statistically significant. CONCLUSION: The present data would suggest a utility of transvaginal ultrasound for the evaluation of the pregnant patient with 94% of distal stones being detected transvaginal versus 29% transabdominally. Additionally, there was significantly increased hydronephrosis and elevated RIs in patients with distal ureteral stones.

Syntactic and semantic errors in radiology reports associated with speech recognition software.

Speech recognition software can increase the frequency of errors in radiology reports, which may affect patient care. We retrieved 213,977 speech recognition software-generated reports from 147 different radiologists and proofread them for errors. Errors were classified as "material" if they were believed to alter interpretation of the report. "Immaterial" errors were subclassified as intrusion/omission or spelling errors. The proportion of errors and error type were compared among individual radiologists, imaging subspecialty, and time periods. In all, 20,759 reports (9.7%) contained errors, of which 3992 (1.9%) were material errors. Among immaterial errors, spelling errors were more common than intrusion/omission errors ( p < .001). Proportion of errors and fraction of material errors varied significantly among radiologists and between imaging subspecialties ( p < .001). Errors were more common in cross-sectional reports, reports reinterpreting results of outside examinations, and procedural studies (all p < .001). Error rate decreased over time ( p < .001), which suggests that a quality control program with regular feedback may reduce errors.

Syntactic and Semantic Errors in Radiology Reports Associated With Speech Recognition Software.

Speech recognition software (SRS) has many benefits, but also increases the frequency of errors in radiology reports, which could impact patient care. As part of a quality control project, 13 trained medical transcriptionists proofread 213,977 SRS-generated signed reports from 147 different radiologists over a 40 month time interval. Errors were classified as "material" if they were believed to alter interpretation of the report. "Immaterial" errors were subclassified as intrusion/omission or spelling errors. The proportion of errors and error type were compared among individual radiologists, imaging subspecialty, and time periods using .2 analysis and multiple logistic regression, as appropriate. 20,759 (9.7%) reports contained errors; 3,992 (1.9%) contained material errors. Among immaterial errors, spelling errors were more common than intrusion/omission errors (P<.001). Error proportion varied significantly among radiologists and between imaging subspecialties (P<.001). Errors were more common in cross-sectional reports (vs. plain radiography) (OR, 3.72), reports reinterpreting results of outside examinations (vs. in-house) (OR, 1.55), and procedural studies (vs. diagnostic) (OR, 1.91) (all P<.001). Dictation microphone upgrade did not affect error rate (P=.06). Error rate decreased over time (P<.001).

Comparison of the applicability of the 2006 and the 2010 cardiac CT angiography appropriate use criteria.

PURPOSE: In a previous study, the 2006 appropriateness criteria (AC) for cardiac CT were applied to 251 patients. It was found that 46% of patients could not be classified, and two observers showed only fair agreement (κ = 0.31) on the assigned appropriateness rating (appropriate, inappropriate, uncertain, or not classifiable). The conclusion was that the 2006 AC were difficult to apply. The AC were revised in 2010. The aim of this study was to determine if the rate of patients not classifiable and interobserver variability had decreased to the point at which the AC could be reasonably applied. METHODS: Medical records of the 251 patients who were classified using the 2006 AC were reviewed by two observers, who attempted to assign the patients' indications using the 2010 AC. Patients for whom no indications could be found were deemed not classifiable. A third observer settled disagreements. The numbers of patients not classifiable using the 2006 and 2010 criteria and the number of patients on whom the two reviewers disagreed on indications were compared using McNemar's test. RESULTS: One hundred fifteen patients (46%) were not classifiable using the 2006 AC. With the 2010 AC, the number of patients not classifiable decreased to 39 (16%) (P < .001). With the 2006 criteria, the observers disagreed on specific indications for 152 patients (61%). With the 2010 criteria, the observers disagreed for 118 patients (47%) (P = .002). CONCLUSIONS: Using the 2010 AC, the number of patients not classifiable and the number of disagreements decreased. Although the rate of patients not classifiable has decreased to an acceptable level, the interobserver variability remains concerning.