Effect of Radiology Study Flow on Report Turnaround Time.

OBJECTIVE: The purpose of this study was to assess the importance of relative value unit (RVU) flow and other factors in report turnaround time (TAT) in emergency radiologic operations. MATERIALS AND METHODS: RVU flow was defined as the normalized (to 60 minutes) total work RVUs for studies performed in a given time interval of 30 minutes (RVU flow 30) or 60 minutes (RVU flow 60). Twenty-five weekday emergency radiology shifts each for four radiologists were randomly selected. The institutional radiology search engine was queried to obtain the following data for each study: study completion time, work RVU, attending radiologist, and report TAT. RVU flow 30, RVU flow 60, presence of resident, and number of hours since start of shift were computed. Two separate multiple linear regression analyses were performed with RVU flow 30 or RVU flow 60 and other factors as independent variables and TAT as the dependent variable. RESULTS: The study included 7378 radiology studies from 100 weekday shifts, from which 1537 RVU flow 30 and 792 RVU flow 60 data points were generated. RVU flow 60 (p = 0.0026) and RVU flow 30 (< 0.0001) were significantly associated with radiology report TAT. One attending radiologist had statistically significant lower TAT 30 and TAT 60, whereas another had a lower TAT 30 but not TAT 60. The presence of a resident was significantly associated with reduced TAT 30 (p = 0.0005) and TAT 60 (p = 0.0028). CONCLUSION: RVU flow 60, RVU flow 30, specific attending radiologist, and presence of a resident are significantly correlated with radiology report TAT. RVU flow should be considered when evaluating radiologist and overall system performance with respect to report TAT.

In vivo comparison of tantalum, tungsten, and bismuth enteric contrast agents to complement intravenous iodine for double-contrast dual-energy CT of the bowel.

To assess the ability of dual-energy CT (DECT) to separate intravenous contrast of bowel wall from intraluminal contrast, we scanned 16 rabbits on a clinical DECT scanner: n = 3 using only iodinated intravenous contrast, and n = 13 double-contrast enhanced scans using iodinated intravenous contrast and experimental enteric non-iodinated contrast agents in the bowel lumen (five bismuth, four tungsten, and four tantalum based). Representative image pairs from conventional CT images and DECT iodine density maps of small bowel (116 pairs from 232 images) were viewed by four abdominal imaging attending radiologists to independently score each comparison pair on a visual analog scale (-100 to +100%) for (1) preference in small bowel wall visualization and (2) preference in completeness of intraluminal enteric contrast subtraction. Median small bowel wall visualization was scored 39 and 42 percentage points (95% CI 30-44% and 36-45%, both p < 0.001) higher for double-contrast DECT than for conventional CT with enteric tungsten and tantalum contrast, respectively. Median small bowel wall visualization for double-contrast DECT was scored 29 and 35 percentage points (95% CI 20-35% and 33-39%, both p < 0.001) higher with enteric tungsten and tantalum, respectively, than with bismuth contrast. Median completeness of intraluminal enteric contrast subtraction in double-contrast DECT iodine density maps was scored 28 and 29 percentage points (95% CI 15-31% and 28-33%, both p < 0.001) higher with enteric tungsten and tantalum, respectively, than with bismuth contrast. Results suggest that in vivo double-contrast DECT with iodinated intravenous and either tantalum- or tungsten-based enteric contrast provides better visualization of small bowel than conventional CT. Copyright © 2016 John Wiley & Sons, Ltd.

Extravasated contrast material in penetrating abdominopelvic trauma: dual-contrast dual-energy CT for improved diagnosis--preliminary results in an animal model.

PURPOSE: To compare the diagnostic performance of dual-energy (DE) computed tomography (CT) with two simultaneously administered contrast agents (hereafter, dual contrast) with that of conventional CT in the evaluation of the presence and source of extravasation in penetrating abdominopelvic trauma. MATERIALS AND METHODS: Institutional animal care and use committee approval was obtained, and the study was performed in accordance with National Institutes of Health guidelines for the care and use of laboratory animals. Five rabbits with bowel trauma, vascular penetrating trauma, or both were imaged with simultaneous iodinated intravenous and bismuth subsalicylate enteric contrast material at DE CT. Four attending radiologists and six radiology residents without prior DE CT experience each evaluated 10 extraluminal collections to identify the vascular and/or enteric origin of extravasation and assess their level of diagnostic confidence, first with virtual monochromatic images simulating conventional CT and then with DE CT material decomposition attenuation maps. RESULTS: Overall accuracy of identification of source of extravasation increased from 78% with conventional CT to 92% with DE CT (157 of 200 diagnoses vs 184 of 200 diagnoses, respectively; P < .001). Nine radiologists were more accurate with DE CT; one had no change. Mean confidence increased from 67% to 81% with DE CT (P < .001). CONCLUSION: In a rabbit abdominopelvic trauma model, dual-contrast DE CT significantly increased accuracy and confidence in the diagnosis of vascular versus enteric extravasated contrast material.

In vivo differentiation of complementary contrast media at dual-energy CT.

PURPOSE: To evaluate the feasibility of using a commercially available clinical dual-energy computed tomographic (CT) scanner to differentiate the in vivo enhancement due to two simultaneously administered contrast media with complementary x-ray attenuation ratios. MATERIALS AND METHODS: Approval from the institutional animal care and use committee was obtained, and National Institutes of Health guidelines for the care and use of laboratory animals were observed. Dual-energy CT was performed in a set of iodine and tungsten solution phantoms and in a rabbit in which iodinated intravenous and bismuth subsalicylate oral contrast media were administered. In addition, a second rabbit was studied after intravenous administration of iodinated and tungsten cluster contrast media. Images were processed to produce virtual monochromatic images that simulated the appearance of conventional single-energy scans, as well as material decomposition images that separate the attenuation due to each contrast medium. RESULTS: Clear separation of each of the contrast media pairs was seen in the phantom and in both in vivo animal models. Separation of bowel lumen from vascular contrast medium allowed visualization of bowel wall enhancement that was obscured by intraluminal bowel contrast medium on conventional CT scans. Separation of two vascular contrast media in different vascular phases enabled acquisition of a perfectly coregistered CT angiogram and venous phase-enhanced CT scan simultaneously in a single examination. CONCLUSION: Commercially available clinical dual-energy CT scanners can help differentiate the enhancement of selected pairs of complementary contrast media in vivo.

Surgical treatment options for subacute ischemia of the hand: case report and literature review.

PURPOSE: The most effective surgical approach to the treatment of digital ischemia has not yet been established. The purpose of this study is to review currently accepted options for revascularization in acute and chronic settings of digital ischemia, and to augment this discussion by describing the approach of our surgical team in a unique case of subacute ischemia. OPERATIVE TECHNIQUE: To restore blood flow to a patient's ischemic hand, we performed a microvascular reconstruction, using a reverse interpositional vein graft with 3 anastomoses: the ulnar artery was used for inflow and the superficial palmar arch and the common digital artery were used for outflow. RESULTS: The patient experienced immediate postoperative pain relief. Blood flow was restored, which prevented digital amputation. The graft remained patent at 18 months' follow-up and the patient exhibited normal motor and sensory function. CONCLUSIONS: Surgical reconstruction of the hand is a viable treatment option for carefully selected patients presenting with subacute digital ischemia. Other medical and surgical techniques have been described in the recent literature, but further study is needed to determine the long-term success of newer microsurgical interventions.