Is there an association between radiologist turnaround time of emergency department abdominal CT studies and radiologic report quality?

The aim of this study was to assess for an association between radiologists' turnaround time (TAT) and report quality for emergency department (ED) abdominopelvic CT examinations. Reports of 60 consecutive ED abdominopelvic CT studies from five abdominal radiologists (300 total reports) were included. An ED radiologist, abdominal radiologist, and ED physician independently evaluated satisfaction with report content (1-10 scale), satisfaction with report clarity (1-10 scale), and extent to which the report advanced the patient on a previously published clinical spectrum scale (1-5 scale). TAT (time between completion of imaging and completion of the final report) and report quality were compared between radiologists using unpaired t tests; associations between TAT and report quality scores for individual radiologists were assessed using Pearson's correlation coefficients. The five radiologists' mean TAT varied from 35 to 53 min. There were significant differences in report content in half of comparisons between radiologists by observer 1 (p ≤ 0.032) and in a minority of comparisons by observer 2 (p ≤ 0.047), in report clarity in majority of comparisons by observer 1 (p ≤ 0.031) and in a minority of comparisons by observer 2 (p ≤ 0.010), and in impact on patient care in a minority of comparisons for all observers (p ≤ 0.047). There were weak positive correlations between TAT and report content and clarity for three radiologists for observer 1 (r = 0.270-0.362) and no correlation between TAT and any report quality measure for remaining combinations of the five radiologists and three observers (r = -0.197 to +0.181). While both TAT and report quality vary between radiologists, these two factors were not associated for individual radiologists.

Impact of size of region-of-interest on differentiation of renal cell carcinoma and renal cysts on multi-phase CT: preliminary findings.

INTRODUCTION: To assess impact of size of regions-of-interest (ROI) on differentiation of RCC and renal cysts using multi-phase CT, with focus on differentiating papillary RCC (pRCC) and cysts given known hypovascularity of pRCC. METHODS: 99 renal lesions (23 pRCC, 47 clear-cell RCC, 7 chromophobe RCC, 22 cysts) underwent multi-phase CT. Subjective presence of visual enhancement was recorded for each lesion. Whole-lesion (WL) ROIs, and small (≤ 5 mm(2)), medium (average size of small and large ROIs), and large (half of lesion diameter) peripherally located partial-lesion (PL) ROIs, were placed on non-contrast and nephrographic phases. Impact of ROI size in separating cysts from all RCC and from pRCC based on increased attenuation between phases was assessed using ROC analysis. RESULTS: Visual enhancement was perceived in 96% of ccRCC, 61% of pRCC, and 9% of cysts. AUCs for separating all RCC and cysts for WL-ROI and small, medium, and large PL-ROIs were 91%, 96%, 91% and 93%, and among lesions without visible enhancement were 60%, 79%, 67% and 67%. AUCs for separating pRCC and cysts for WL-ROI and small, medium, and large PL-ROIs were 78%, 92%, 82% and 84%, and among lesions without visible enhancement were 64%, 88%, 69% and 69%. CONCLUSION: Small PL-ROIs had higher accuracy than WL-ROI or other PL-ROIs in separating RCC from cysts, with greater impact in differentiating pRCC from cysts and differentiating lesions without visible enhancement. Thus, when evaluating renal lesions using multi-phase CT, we suggest placing small peripheral ROIs for highest accuracy in distinguishing renal malignancy and benign cysts.

Utility of MRI features in differentiation of central renal cell carcinoma and renal pelvic urothelial carcinoma.

OBJECTIVE: The purpose of this article is to evaluate the utility of various morphologic and quantitative MRI features in differentiating central renal cell carcinoma (RCC) from renal pelvic urothelial carcinoma. MATERIALS AND METHODS: Sixty patients (39 men and 21 women; mean [± SD] age, 65 ± 14 years; 48 with central RCC and 12 with renal pelvic urothelial carcinoma) who underwent MRI, including diffusion-weighted imaging (b values, 0, 400, and 800 s/mm(2)) and dynamic contrast-enhanced imaging, before histopathologic confirmation were included. Tumor T2 signal intensity and apparent diffusion coefficients (ADCs) were measured and normalized to muscle and CSF (hereafter referred to as normalized T2 signal and normalized ADC, respectively) and then were compared using receiver operating characteristic analysis. Also, two blinded radiologists independently assessed all tumors for various qualitative features, which were compared with the Fisher exact test and unpaired Student t test. RESULTS: Urothelial carcinoma exhibited significantly lower normalized ADC than did RCC (p = 0.008), but no significant difference was seen in ADC or normalized T2 signal intensity (p = 0.247-0.773). Normalized ADC had the highest area under the curve (0.757); normalized ADC below an optimal threshold of 0.451 was associated with sensitivity of 83% and specificity of 71% for diagnosing urothelial carcinoma. Features that were significantly more prevalent in urothelial carcinoma included global impression of urothelial carcinoma, location centered within the collecting system, collecting system defect, extension to the ureteropelvic junction, preserved renal shape, absence of cystic or necrotic areas, absence of hemorrhage, homogeneous enhancement, and hypovascularity (all p < 0.033). Increased T1 signal intensity suggestive of hemorrhage was significantly more prevalent in RCC (p = 0.02). Interreader agreement for the subjective features ranged from 61.7% to 98.3%. CONCLUSION: In addition to various qualitative MRI parameters, normalized ADC has utility in differentiating central RCC from renal pelvic urothelial carcinoma. Such differentiation may assist decisions regarding possible biopsy and treatment planning.

Prostate cancer: comparison of dynamic contrast-enhanced MRI techniques for localization of peripheral zone tumor.

OBJECTIVE: The objective of this study was to compare the performance of different methodologies for interpretation of dynamic contrast-enhanced MRI (DCE-MRI) in localization of peripheral zone prostate cancer. MATERIALS AND METHODS: Forty-three men (mean age, 59±8 years) with biopsy-proven prostate cancer who underwent prostate MRI including DCE-MRI before prostatectomy were included. Two observers independently reviewed DCE-MRI data using three methodologies: qualitative, in which kinetic curves of signal intensity versus time were generated for foci showing rapid enhancement on subtracted contrast-enhanced images; semiquantitative, in which a biexponential heuristic model was used to generate color-coded maps depicting maximum slope and washout of contrast enhancement; and quantitative, in which a Tofts model was used to generate color-coded influx rate transfer constant (Ktrans) and efflux rate transfer constant (Kep) maps. Findings were stratified by whether suspicious foci showed evidence of washout with each method and compared with histopathologic results in each sextant. RESULTS: There was similar accuracy for the semiquantitative and quantitative models for both observers irrespective of requiring evidence of washout. For the more experienced observer, requiring washout resulted in lower sensitivity and higher specificity for the qualitative and semiquantitative models. Also for the more experienced observer, use of either a semiquantitative or quantitative model provided greater sensitivity compared with a qualitative model when requiring washout. There was no association between tumor detection and Gleason score for any DCE-MRI methodology for either reader. CONCLUSION: For the experienced reader, sensitivity for peripheral zone tumor was increased by use of either a semiquantitative or quantitative model compared with a qualitative model and decreased by requiring washout. We failed to identify a difference in performance between semiquantitative and quantitative models.

Comparison of CT and MRI findings in the differentiation of acute from chronic cholecystitis.

We compared individual computed tomography (CT) and MRI findings in differentiating acute from chronic cholecystitis. Thirty-seven patients undergoing both studies before cholecystectomy were included. Two radiologists (R1/R2) independently assessed all cases. For detecting acute cholecystitis, MRI showed better sensitivity (R1) using gallbladder wall thickening, accuracy (R1) and sensitivity (R1) using gallstones, sensitivity (R1 and R2) and accuracy (R2) using gallbladder wall hyperemia, accuracy (R1 and R2) using gallbladder wall defect, and accuracy (R2) using adjacent liver hyperemia (P=.004-.063). MRI also showed better specificity (R2) using pericholecystic fat stranding (P=.016). Overall, several findings showed better sensitivity and/or accuracy for acute cholecystitis on MRI than CT.

Recommendations for additional imaging on emergency department CT examinations: comparison of emergency- and organ-based subspecialty radiologists.

PURPOSE: Past studies have identified a high frequency of recommendations for additional imaging (RAI) for computed tomography (CT) studies performed in an emergency department (ED), thereby potentially contributing to increased imaging utilization and costs. The purpose of this study was to compare rates of RAI within the ED setting between ED-based and organ-based subspecialty radiologists. METHODS: We identified 600 ED CT studies, comprising 200 head, chest, and abdominal CT studies, split equally between cases reviewed by ED-based and organ-based radiologists. Frequency of RAI for the three examinations was compared between these subspecialty groups. RESULTS: Frequencies of RAI were 21.5 %, 13.5 %, and 5.5 % for CT examinations of the chest, abdomen, and brain, respectively. There was a significantly higher frequency of RAI for chest CT studies interpreted by chest radiologists than by ED radiologists (28.0 % vs. 15.0 %, respectively, p = 0.036), largely due to a higher rate of RAI for incidentally detected lung nodules and masses as well as other pulmonary parenchymal abnormalities by chest radiologists. There was no significant difference in RAI on brain or abdominal CT studies between the two groups (p = 0.426-1.0). However, on abdominal studies, only ED-based radiologists provided RAI for abnormalities of the bowel or uterus, while only organ-based radiologists provided RAI for pancreatic abnormalities. Only 25.6 % of RAI were subsequently performed at our institution. CONCLUSION: For chest CT studies performed at the authors' institution, differences in management of incidental pulmonary nodules contributed to a significantly higher frequency of RAI by chest radiologists than by ED-based radiologists. Further investigation of the impact of these differences on cost and patient outcomes is warranted.