Assessment of Cirrhotic Liver Enhancement With Multiphasic Computed Tomography Using a Faster Injection Rate, Late Arterial Phase, and Weight-Based Contrast Dosing.

PURPOSE: This study aimed to update our liver computed tomography (CT) protocol according to published guidelines, and to quantitatively evaluate the effect of these modifications. METHODS: The modified liver CT protocol employed a faster injection rate (5 vs 3 mL/s), later arterial phase (20-second vs 10-second postbolus trigger), and weight-based dosing of iodinated contrast (1.7 mL/kg vs 100 mL fixed dose). Liver and vascular attenuation values were measured on CTs of patients with cirrhosis from January to September 2015 (old protocol, n = 49) and from October to December 2015 (modified protocol, n = 31). CTs were considered adequate if liver enhancement exceeded 50 Hounsfield units (HU) in portal venous phase, or when the unenhanced phase was unavailable, if a minimum iodine concentration of 500 mg I/kg was achieved. Attenuations and iodine concentrations were compared using the t test and the number of suboptimal studies was compared with Fisher's exact test. RESULTS: CTs acquired with the modified protocol demonstrated higher aortic (P = .001) and portal vein (P < .0001) attenuations in the arterial phase as well as greater hepatic attenuation on all postcontrast phases (P = .0006, .002, and .003 for arterial, venous, and equilibrium phases, respectively). Hepatic enhancement in the portal venous phase (61 ± 15 HU vs 51 ± 16 HU; P = .0282) and iodine concentrations (595 ± 88 mg I/kg vs 456 ± 112 mg I/kg; P < .0001) were improved, and the number of suboptimal studies was reduced from 57% to 23% (P = .01). CONCLUSIONS: A liver CT protocol with later arterial phase, faster injection rate, and weight-based dosing of intravenous contrast significantly improves liver enhancement and iodine concentrations in patients with cirrhosis, resulting in significantly fewer suboptimal studies.

ACR Select Identifies Inappropriate Underutilization of Magnetic Resonance Imaging in British Columbia.

PURPOSE: A study was performed to evaluate the ACR Select software in determining the level of appropriateness of computed tomography (CT) and magnetic resonance imaging (MRI) in Island Health in British Columbia. METHODS: A total of 1228 consecutive CT and MRI studies performed in a 3-day period were entered into a software program provided by the National Decision Support Company based on the ACR Appropriateness Criteria. The program was able to analyze 93% (1141) of these studies. A subset of these requisitions was manually reviewed. RESULTS: The software program demonstrated a very low 2.5% inappropriate rate and manual review showed an even lower number of 0.6%. In a sample of studies deemed to be appropriate by the software, manual review agreed with this ranking in all cases. In addition, in 20% of cases where CT was done, the software program suggested that MRI would be a more appropriate choice. CONCLUSIONS: First, the ACR Select software is a useful tool to assess appropriateness of CT and MRI, although it may underestimate the level of appropriateness of studies labeled as inappropriate. Second, CT and MRI are being ordered appropriately in Island Health in British Columbia. The software recommendation of MRI as more appropriate in 20% of cases where CT was done suggests a lack of MRI resources in Island Health.

Vasitis: clinical and ultrasound confusion with inguinal hernia clarified by computed tomography.

Vasitis or inflammation of the vas deferens is a rarely described condition categorized by Chan & Schlegel1 as either generally asymptomatic vasitis nodosa or the acutely painful infectious vasitis. Clinically, infectious vasitis presents with nonspecific symptoms of localized pain and swelling that can be confused with other, more common conditions such as epididymitis, orchitis, testicular torsion, and inguinal hernia. Ultrasound with duplex Doppler scanning can be used to exclude epididymitis, orchitis, and testicular torsion. On the other hand, while inguinal hernia is difficult to differentiate from vasitis using ultrasound, computed tomography (CT) is diagnostic. We describe 2 cases of vasitis with clinical and ultrasound findings that initially were interpreted as inguinal hernias. In both patients, CT was diagnostic for vasitis showing an edematous spermatic cord and no hernia. Urine cultures in both patients were negative, but the symptoms resolved with antibiotic treatment.