Cost-effectiveness analysis of including contrast-enhanced ultrasound in management of pancreatic cystic neoplasms.

PURPOSE: Pancreatic cystic neoplasms (PCN) management consists of non-invasive imaging studies (CT, MRI), with a high resource burden. We aimed to determine the cost-effectiveness of including contrast-enhanced ultrasound (CEUS) in the management of PCN without risk features. MATERIALS AND METHODS: By using a decision-tree model in a hypothetical cohort of patients, we compared management strategy including CEUS with the latest Fukuoka consensus, European and Italian guidelines. Our strategy for BD-IPMN/MCN < 1 cm includes 1 CEUS annually. For those between 1 and 2 cm, it includes CEUS 4 times/year during the first year, then 3 times/year for 4 years and then annually. For those between 2 and 3 cm, it comprises MRI twice/year during the first one, then alternating 2 CEUS and 1 MRI yearly. RESULTS: CEUS surveillance is the dominant strategy in all scenarios. CEUS surveillance average cost is 1,984.72 €, mean QALY 11.79 and mean ICER 181.99 €. If willingness to pay is 30,000 €, 45% of patients undergone CEUS surveillance of BDIPMN/MCN < 1 cm would be within budget. CONCLUSION: Guidelines strategies are very effective, but costs are relatively high from a policy perspective. CEUS surveillance may be a cost-effective strategy yielding a nearly high QALYs, an acceptable ICER, and a lower cost.

Management of vertebral compression fractures: the role of dual-energy CT in clinical practice.

PURPOSE: To evaluate the role of dual-energy computed tomography (DECT) in the management of vertebral compression fractures in clinical practice. MATERIALS AND METHODS: This retrospective IRB-approved study included 497 consecutive patients with suspected acute vertebral fractures, imaged either by DECT (group 1) or MRI (group 2) before vertebroplasty. The site, number and type of fractures at imaging findings, and clinical outcome based on any change in pain (DELTA-VAS), before (VAS-pre) and after treatment (VAS-post), were determined and compared. Two radiologists evaluated DECT and MRI images (15 and 5 years of experience, respectively), and inter-observer and intra-observer agreement were calculated using k statistics. RESULTS: Both in the control group (n = 124) and in the group of patients treated by vertebroplasty (n = 373), the clinical outcome was not influenced by the imaging approach adopted, with a DELTA-VAS of 5.45 and 6.42 in the DECT group and 5.12 and 6.65 in the MRI group (p = 0.326; p = 0.44). In the group of treated patients, sex, age, lumbar fractures, multiple fractures, previous fractures, Genant grade, involvement of anterior apex or superior endplates, and increased spinal curvatures were similar (p = ns); however, dorsal fractures were more prevalent in group 1 (p = 0.0197). Before treatment, the mean VAS-pre was 8.74 in group 1 (DECT) and 8.65 in group 2 (MRI) (p = 0.301), whereas after treatment, the mean VAS-post value was 2.32 in group 1 (p = 0.0001), and 2.00 in group 2 (p = 0.0001). The DELTA-VAS was 6.42 in the group of patients imaged using DECT and 6.65 in the group imaged using MRI (p = 0.326). Inter-observer and intra-observer agreement were 0.85 and 0.89 for DECT, and 0.88 and 0.91 for MRI, respectively. CONCLUSION: The outcome of vertebral compression fracture management was no different between the two groups of patients studied.

Identification of pulmonary embolism: diagnostic accuracy of venous-phase dual-energy CT in comparison to pulmonary arteries CT angiography.

OBJECTIVES: To evaluate the diagnostic accuracy of venous-phase dual-energy computed tomography (VP-DECT) in the identification of PE compared with standard CT pulmonary angiography (CTPA). METHODS: This prospective IRB-approved study included 61 consecutive oncology patients (35 females, 26 males, mean age 66.91 years) examined by CTPA and VP-DECT. DECT data were post-processed on a SyngoVia workstation to obtain monoenergetic images (MEI+). The diagnosis of PE was based on the presence of any vascular perfusion defects. DECT images were evaluated independently by two radiologists (8 and 16 years of experience). A consensus reading of CTPA images (two senior radiologists, 18 and 24 years of experience) represented the reference for diagnosis. The diagnostic accuracy values of VP-DECT on a per-patient and per-lobe basis were assessed. Interobserver agreement was calculated using k-statistics. A value of p < 0.05 was considered statistically significant. RESULTS: Thirty of 61 patients (49.18%) were diagnosed with PE by CTPA, with 57/366 lobes being involved (15.57%). The sensitivity and specificity of the per-patient analysis of VP-DECT images were 90.0% (27/30) and 100% (31/31) respectively, for both readers. As concerns the per-lobe analysis, the sensitivity ranged from 100% for the right lower lobe to 50% for the left upper lobe for reader 1, and from 100% for the left upper lobe to 69.23% for the lingula for reader 2. The interobserver agreement ranged from 0.8671 (patients' analysis) to 0.6419 (lobes' analysis). CONCLUSION: VP-DECT could be considered an accurate imaging tool for diagnosing PE in a selected, high-prevalence population, compared with CTPA. KEY POINTS: • With regard to the patients' analysis, venous-phase DECT sensitivity and specificity in diagnosing pulmonary embolism were 90% and 100%, respectively, for both readers. • With regard to the lobes' analysis, the sensitivity ranged from 100 to 50%, for reader 1, and from 100 to 69.23%, for reader 2, respectively. • The sensitivity and specificity of lung perfusion maps obtained from venous DECT were 73.33% and 67.74% as concerns the patients' analysis and 71.92% and 75.72% as regards the lobes' analysis, respectively.

Identification of bone marrow edema of the knee: diagnostic accuracy of dual-energy CT in comparison with MRI.

BACKGROUND: To assess the diagnostic accuracy of dual-energy computed tomography (DECT) in diagnosing bone marrow edema (BME) of the knee in traumatic and non-traumatic patients. METHODS: This prospective IRB approved study included 33 consecutive patients (20 males, 13 females; mean age of 52.2 years) evaluated with DECT (80 and 150 kV) and MRI within 6 days. Two experienced radiologists qualitatively and quantitatively evaluated DECT images. The accuracy values were calculated by using receiver operator curves (ROC) and area under the curve (AUC), using MRI as the reference standard. Inter-observer and intra-observer agreement were calculated with k-statistics. A p < 0.05 was considered statistically significant. RESULTS: MRI depicted BME in 25/33 patients (75.7%). The sensitivity, specificity, PPV, NPV, and accuracy of per-partition qualitative analysis were 92.9, 92.9, 78.2, 97.9, and 92.9%, for reader 1, and 88.2, 93.9, 79.8, 96.6, and 92.6%, for reader 2, respectively. The inter-observer agreement was substantial (k = 0.793) and the intra-observer agreement was near-perfect (k = 0.844). At the quantitative analysis, a significant difference (p < 0.001) was depicted between the density values of positive (mean 3.6 ± 25.3 HU) and negative cases (mean - 72.2 ± 45.1 HU). By using - 15 HU cutoff to identify BME, sensitivity, specificity, PPV, NPV, and accuracy of DECT were 84.7, 93.6, 78.2, 95.7, and 91.6%, respectively. CONCLUSION: DECT can accurately identify BME of the knee.

Bone marrow edema around the hip in non-traumatic pain: dual-energy CT vs MRI.

OBJECTIVES: To evaluate the diagnostic accuracy of dual-energy computed tomography (DECT) in identifying bone marrow edema (BME) around the hip joint in non-traumatic patients. METHODS: This prospective IRB-approved study was conducted between January 2019 and October 2019 and included 59 consecutive patients (18 males, 41 females; mean age 61.5 years, range 32-82) who were assessed by DECT and magnetic resonance imaging (MRI) within a 5-day period. Diagnostic accuracy values for diagnosing BME on a per-patient and on a per-partition-basis analysis were calculated for DECT images by two readers (R1 and R2, with 15 and 10 years of experience, respectively), using MRI as reference for diagnosis. Inter-observer agreements were calculated with k-statistics. A p value of < 0.05 was considered as statistically significant. RESULTS: MRI depicted BME in 44/59 patients (74.58%), with the involvement of 83/708 (11.72%) partitions. The sensitivity, specificity, and accuracy of R1 and R2 were 95.45% (42/44), 86.67% (13/15), and 93.22% (55/59) for R1, and 86.36% (38/44), 80.00% (12/15), and 84.75% (50/59) for R2. For both readers, the BME detection rate was higher in patients with severe edema (100%) in comparison to patients with mild edema (91.30% and 73.91%). In the partition-basis analysis, sensitivity, specificity, and accuracy ranges were 33.3 to 100%, 91.84 to 100%, and 88.14 to 100%, respectively. The inter-observer agreement for patients' analysis was substantial (k = 0.7065), whereas for partition analysis ranged from fair (k = 0.2976) to near-perfect (k = 1.000). CONCLUSION: DECT can accurately identify BME around the hip joint, in comparison to MRI. KEY POINTS: • DECT can accurately identify bone marrow edema around the hip joint in a cohort of non-traumatic patients. • The detection of bone marrow edema by means of DECT may help the radiologist to identify associated findings, including avascular necrosis of the femoral head and insufficiency or stress fractures. • In cases of patients suffering from groin pain with bone marrow edema identified by DECT, the concurrent reading of high-resolution conventional CT images may increase the confidence of diagnosis and/or reduce the reading time.

Activity-Based Cost Analysis of Including Contrast-Enhanced Ultrasound (CEUS) in the Diagnostic Pathway of Focal Pancreatic Lesions Detected by Abdominal Ultrasound.

PURPOSE: To perform an activity-based cost analysis of the inclusion of contrast-enhanced ultrasound (CEUS) in the diagnostic pathway of newly detected focal pancreatic lesions revealed by abdominal ultrasound (US) in comparison to computed tomography (CT) and magnetic resonance imaging (MRI). MATERIALS AND METHODS: Over a 14-year period, 977 patients with newly detected focal pancreatic lesions on US and subsequently studied with CEUS and/or CT and MRI were included. The cost of equipment, materials and human resources for every imaging method was calculated. We analyzed the costs in different scenarios considering whether or not CT or MRI was required in the diagnostic pathway. The savings (R) were calculated by subtracting the differential cost of CEUS from the eliminated third-level exam (CCEUS: CEUS cost; CCT: CT cost; CMRI: MRI cost) compared to conventional ultrasound (CCEUS-CUS): R = CCT-(CCEUS-CUS) or R = CMRI-(CCEUS-CUS). RESULTS: Total costs were: US 28.39 €; CEUS 70.50 €; CT 106.23 €; MRI 219.61 €. In 388/563 patients CEUS characterized the pancreatic lesion as solid, with only CT being performed as a second-level investigation: the savings were 68 870.36 €. In 266/414 patients CEUS diagnosed lesions as cystic, with only MRI being performed as a second-level examination: the savings were 16 825.07 €. Considering the whole diagnostic pathway of the patients, the cost savings were 76 809.35 € for solid lesions and 26 242.49 € for cystic lesions, with overall savings of 103 051.84 €. CONCLUSION: CEUS represents a cost-effective imaging method for the differentiation of focal pancreatic lesions and could guide the selection of the best imaging modality for preoperative assessment, thereby optimizing resources and securing the diagnostic pathway.

CEUS versus CT Angiography in the follow-up of abdominal aortic endoprostheses: diagnostic accuracy and activity-based cost analysis.

PURPOSE: To evaluate diagnostic accuracy and to perform an activity-based cost analysis of contrast-enhanced ultrasonography (CEUS) compared to computed tomography (CT) during annual surveillance after abdominal aortic aneurysm repair with endovascular procedure (EVAR). MATERIALS AND METHODS: This retrospective study included 137 patients in post-EVAR follow-up over a 6-year period (average post-operatory follow-up without aneurysm sac volumetric reduction). Sensitivity, specificity, positive predictive values, negative predictive values and accuracy were considered for CEUS using CT angiography (CTA) as reference standard. An activity-based cost analysis was performed to evaluate potential savings due to the introduction of CEUS as an alternative to CT, after the first year of postoperative negative controls. RESULTS: CEUS reported accuracy, sensitivity, specificity, positive predictive values, negative predictive values of 97.4, 96, 100, 100 and 93.1% in the detection and characterization of endoleaks. CEUS cost was € 84.7, and CTA cost was € 157.77, with a differential cost of € 73.07; using CEUS as an alternative to CT allowed a potential saving of 50.052,95 € during follow-up. CONCLUSIONS: CEUS is an accurate and cheap imaging method in post-EVAR follow-up patients, and it could be considered as a valid alternative to CTA, after the first year of negative controls, reducing the number of unnecessary CT examinations.

Characterization of adrenal lesions using MDCT wash-out parameters: diagnostic accuracy of several combinations of intermediate and delayed phases.

PURPOSE: To evaluate the diagnostic accuracy of wash-out parameters calculated using multiple intermediate and delayed phases. MATERIALS AND METHODS: This prospective study had institutional review board approval and informed consent was obtained from all patients. Between January 2012 and October 2016, 108 consecutive oncologic patients (59 males, 49 females, mean age 52.6 years; 129 diagnosed lesions) underwent multiphasic CT protocol including unenhanced (UE), arterial (AE), portal (PE), 5-min (DE-5) and the 15-min (DE-15) delayed phases of adrenal glands. All images were randomly reviewed in consensus by two radiologists experienced in abdominal CT, unaware of clinical or pathologic data. Location, size and density were recorded. Absolute wash-out, percentage wash-out (PWO) and percentage enhancement wash-out ratio were calculated. The thresholds yielding the best accuracy in differentiating adenomas from nonadenomas were retrospectively determined on the basis of ROC curves. The corresponding diagnostic accuracy values were calculated. Paired sample t test was used to assess differences among imaging parameters within subgroups. Student t test was applied to compare lesions between independent subgroups. p values ≤ 0.05 were considered significant. RESULTS: The final diagnosis included 82 adenomas (62 lipid-rich and 20 lipid-poor) and 47 nonadenomas (42 metastases, 3 pheochromocytomas, 2 carcinomas). All the 62 lipid-rich adenomas were correctly diagnosed as benign lesions on the basis of their UE attenuation < 10 HU. The PEAK attenuation was achieved during AE phase for 51/129 lesions (39.5%) and at the time of PE phase in 78/129 lesions (60.5%). The best overall accuracy in diagnosing adenomas (97.6%; 126/129 lesions correctly diagnosed) was obtained using 40% threshold for calculating PWO from PEAK to DE-15 scan. CONCLUSIONS: If only an intermediate phase is available, the 15-min delayed scan should be acquired to avoid any drop in diagnostic accuracy. The availability of two intermediate phase may be used to easy CT schedule by obviating the need to acquire a longer delayed phase.

Both resistance training and aerobic training reduce hepatic fat content in type 2 diabetic subjects with nonalcoholic fatty liver disease (the RAED2 Randomized Trial).

UNLABELLED: Although lifestyle interventions are considered the first-line therapy for nonalcoholic fatty liver disease (NAFLD), which is extremely common in people with type 2 diabetes, no intervention studies have compared the effects of aerobic (AER) or resistance (RES) training on hepatic fat content in type 2 diabetic subjects with NAFLD. In this randomized controlled trial, we compared the 4-month effects of either AER or RES training on insulin sensitivity (by hyperinsulinemic euglycemic clamp), body composition (by dual-energy X-ray absorptiometry), as well as hepatic fat content and visceral (VAT), superficial (SSAT), and deep (DSAT) subcutaneous abdominal adipose tissue (all quantified by an in-opposed-phase magnetic resonance imaging technique) in 31 sedentary adults with type 2 diabetes and NAFLD. After training, hepatic fat content was markedly reduced (P < 0.001), to a similar extent, in both the AER and the RES training groups (mean relative reduction from baseline [95% confidence interval] -32.8% [-58.20 to -7.52] versus -25.9% [-50.92 to -0.94], respectively). Additionally, hepatic steatosis (defined as hepatic fat content >5.56%) disappeared in about one-quarter of the patients in each intervention group (23.1% in the AER group and 23.5% in the RES group). Insulin sensitivity during euglycemic clamp was increased, whereas total body fat mass, VAT, SSAT, and hemoglobin A1c were reduced comparably in both intervention groups. CONCLUSION: This is the first randomized controlled study to demonstrate that resistance training and aerobic training are equally effective in reducing hepatic fat content among type 2 diabetic patients with NAFLD.

Magnetic resonance imaging short protocols for intraductal papillary mucinous neoplasm (IPMN) surveillance: The time has come.

BACKGROUND/OBJECTIVES: To analyze the diagnostic performance of three short magnetic resonance imaging (MRI) protocols for the follow-up of pancratic intraductal papillary mucinous neoplasms (IPMN). METHODS: Follow-up MRI examinations of 287 patients with IPMN performed in two centers were retrospectively retrieved. Four MRI protocols were identified as follows: T1-weighted (T1w), T2-weighted (T2w), and MRCP sequences (protocol 1); T1w, T2w, MRCP, and diffusion-weighted (DWI) sequences (protocol 2); T1w, T2w, MRCP, and post-contrast T1w-sequences (protocol 3); and a comprehensive protocol including all previous sequences (protocol 4). Three radiologists with different experience in abdominal imaging expressed their opinion upon the optimal patient's management upon the evaluation of each protocol. Intra-and inter-observer agreement and concordance with the clinical decision expressed by a pancreatic surgeon were calculated with Cohen's kappa test. RESULTS: 223 patients were included (66±10 years; 92 men, 131 women). 143 patients had branch-duct-IPMNs, 25 main-duct-IPMNs and 55 mixed-type-IPMNs. 79 patients underwent surgery, resulting in 52 high-grade dysplasia (HGD) and 27 low-grade dysplasia (LGD). Concordance for the expert reader between protocols 1, 2 and 3 and the actual clinical decision were 0.63, 0.72, and 0.74 respectively (95% CI, 0.53-0.73, 0.63-0.81, and 0.65-0.83). Inter-observer agreement between reader 1 and reader 2, reader 1 and reader 3, and reader 2 and reader 3 were: 0.71, 0.50, and 0.75 for protocol 1 (95% CI, 0.63-0.81, 0.40-0.60, and 0.66-0.84);0.68, 0.54, and 0.84 for protocol 2 (95% CI, 0.59-0.77, 0.44-0.64, and 0.76-0.91); and 0.77, 0.65, and 0.86 for protocol 3 (95% CI, 0.69-0.86, 0.55-0.74, and 0.80-0.93). CONCLUSIONS: Short MRI protocol is suitable for IPMN surveillance.

Quantitative Assessment of Lung Volumes and Enhancement in Patients with COVID-19: Role of Dual-Energy CT.

Dual-energy computed tomography (DECT) has been used for detecting pulmonary embolism, but the role of lung perfusion DECT as a predictor of prognosis of coronavirus disease 2019 (COVID-19) has not been defined yet. The aim of our study was to explore whether the enhancement pattern in COVID-19+ patients relates to the disease outcome. A secondary aim was to compare the lung volumes in two subgroups of patients. In this observational study, we considered all consecutive COVID-19+ patients who presented to the emergency room between January 2021 and December 2021 with respiratory symptoms (with mild to absent lung consolidation) and were studied by chest contrast-enhanced DECT to be eligible. Two experienced radiologists post-processed the images using the "lung-analysis" software (SyngoVia). Absolute and relative enhancement lung volumes were assessed. Patients were stratified in two subgroups depending on clinical outcome at 30 days: (i) good outcome (i.e., discharge, absence of clinical or imaging signs of disease); (ii) bad outcome (i.e., hospitalization, death). Patient sub-groups were compared using chi-square test or Fisher test for qualitative parameters, chi-square test or Spearman's Rho test for quantitative parameters, Students' t-test for parametric variables and Wilcoxon test for non-parametric variables. We enrolled 78 patients (45M), of whom, 16.7% had good outcomes. We did not observe any significant differences between the two groups, both in terms of the total enhancement evaluation (p = 0.679) and of the relative enhancement (p = 0.918). In contrast, the average lung volume of good outcome patients (mean value of 4262 mL) was significantly larger than that of bad outcome patients (mean value of 3577.8 mL), p = 0.0116. All COVID-19+ patients, with either good or bad outcomes, presented similar enhancement parameters and relative enhancements, underlining no differences in lung perfusion. Conversely, a significant drop in lung volume was identified in the bad outcome subgroup eligible compared to the good outcome subgroup.

Cost-effectiveness analysis of short biparametric magnetic resonance imaging protocol in men at risk of prostate cancer.

OBJECTIVES: To compare the cost-effectiveness of a short biparametric MRI (BP-MRI) with that of contrast-enhanced multiparametric MRI (MP-MRI) for the detection of prostate cancer in men with elevated prostatespecific antigen (PSA) levels. MATERIALS AND METHODS: We compared two diagnostic procedures for detection of prostate cancer (Pca), BP-MRI and MP-MRI, in terms of quality-adjusted life years (QALY), incremental costeffectiveness ratio (ICER) and net monetary benefit (NMB) for a hypothetical cohort of 10,000 patients. We compared two scenarios in which different protocols would be used for the early diagnosis of prostate cancer in relation to PSA values. Scenario 1. BP-MRI/MP-MRI yearly if > 3.0 ng/ml, every 2 years otherwise; Scenario 2. BP-MRI/MP-MRI yearly with age-dependent threshold 3.5 ng/ml (50-59 years), 4.5 ng/ml (60-69 years), 6.5 ng/ml (70-79 years). RESULTS: BP-MRI was more effective than the comparator in terms of cost (160.10 € vs 249.99€) QALYs (a mean of 9.12 vs 8.46), ICER (a mean of 232.45) and NMB (a mean of 273.439 vs 251.863). BP-MRI was dominant, being more effective and less expensive, with a lower social cost. Scenario 2 was more cost-effective compared to scenario 1. CONCLUSIONS: Our results confirmed the hypothesis that a short bi-parametric MRI protocol represents a cost-efficient procedure, optimizing resources in a policy perspective.

Role of CT colonography in differentiating sigmoid cancer from chronic diverticular disease.

PURPOSE: To evaluate the accuracy of computed tomography colonography (CTC) in differentiating chronic diverticular disease from colorectal cancer (CRC), using morphological and textural parameters. MATERIALS AND METHODS: We included 95 consecutive patients with histologically proven chronic diverticular disease (n = 53) or CRC (n = 42) who underwent CTC. One radiologist, unaware of histological findings, evaluated CTC studies for the presence of potential discriminators including: maximum thickness, involved segment length, shouldering phenomenon, growth pattern, diverticula, fascia thickening, fat tissue edema, loco-regional lymph nodes, mucosal pattern. Another radiologist performed volumetric texture analysis on the involved segment. RESULTS: Several qualitative imaging parameters resulted to significantly correlated with colorectal cancer, including absence of diverticula in the affected segment, straightened growth pattern and shouldering phenomenon. A maximum wall thickness/involved segment length ratio < 0.1 had 98% specificity and 47% sensitivity in identifying diverticular disease. Regarding first-order texture analysis parameters, kurtosis resulted to be significantly different between the two groups. CONCLUSIONS: Absence of diverticula, straightened growth pattern and shouldering phenomenon are significantly associated with CRC (71-91% sensitivity; 82-91%).

Three-dimensional morphology of heel fat pad: an in vivo computed tomography study.

Heel fat pad cushioning efficiency is the result of its structure, shape and thickness. However, while a number of studies have investigated heel fat pad (HFP) anatomy, structural behavior and material properties, no previous study has described its three-dimensional morphology in situ. The assessment of the healthy, unloaded, three-dimensional morphology of heel pad may contribute to deepen the understanding of its role and behavior during locomotion. It is the basis for the assessment of possible HFP morphological modifications due to changes in the amount or distribution of the loads normally sustained by the foot. It may also help in guiding the surgical reconstruction of the pad and in improving footwear design, as well as in developing a correct heel pad geometry for finite element models of the foot. Therefore the purpose of this study was to obtain a complete analysis of HFP three-dimensional morphology in situ. The right foot of nine healthy volunteers was scanned with computed tomography. A methodological approach that maximizes reliability and repeatability of the data was developed by building a device to lock the foot in a neutral position with respect to the scan planes during image acquisition. Scan data were used to reconstruct virtual three-dimensional models for both the calcaneus and HFP. A set of virtual coronal and axial sections were extracted from the three-dimensional model of each HFP and processed to extract a set of one- and two-dimensional morphometrical measurements for a detailed description of heel pad morphology. The tissue exhibited a consistent and sophisticated morphology that may reflect the biomechanics of the foot support. HFP was found to be have a crest on its anterior dorsal surface, flanges on the sides and posteriorly, and a thick portion that reached and covered the posterior surface of the calcaneus and the achilles tendon insertion. Its anterior internal portion was thinner and a lump of fat was consistently present in this region. Finally, HFP was found to be thicker in males than in females.

Freehand liver volumetry by using an electromagnetic pen tablet: accuracy, precision, and rapidity.

The purpose of this study is to assess the accuracy, precision, and rapidity of liver volumes calculated by using a freehand electromagnetic pen tablet contourtracing method as compared with the volumes calculated by using the standard optical mouse contourtracing method. The imaging data used as input for accuracy and precision testing were computed by software developed in our institution. This computer software can generate models of solid organs and allows both standard mouse-based and electromagnetic pen-driven segmentation (number of data sets, n = 70). The images used as input for rapidity testing was partly computed by modeling software (n = 70) and partly selected from contrast-enhanced computed tomography (CT) examinations (n = 12). Mean volumes and time required to perform the segmentation, along with standard deviation and range values with both techniques, were calculated. Student's t test was used to assess significance regarding mean volumes and time calculated by using both segmentation techniques on phantom and CT data sets. P value was also calculated. The mean volume difference was significantly lower with the use of the freehand electromagnetic pen as compared with the optical mouse (0.2% vs. 1.8%; P < .001). The mean segmentation time per patient was significantly shorter with the use of the freehand electromagnetic pen contourtracing method (354.5 vs. 499.1 s on phantoms; 457.4 vs. 610.0 s on CT images; P < .001). Freehand electromagnetic pen-based volumetric technique represents a technologic advancement over manual mouse-based contourtracing because of the superior statistical accuracy and sensibly shorter time required. Further studies focused on intra- and interobserver variability of the technique need to be performed before its introduction in clinical application.

Identification of bone marrow edema around the ankle joint in non-traumatic patients: Diagnostic accuracy of dual-energy computed tomography.

OBJECTIVES: To evaluate the diagnostic accuracy of DECT in the identification of BME of the ankle in non-traumatic patients. METHODS: This prospective institutional review board approved study included 40 consecutive patients (21 males and 19 females, mean age 56.8 years, SD = 11.37) that were examined using DECT and MRI in the period between April 2019 and January 2020. Two radiologists (7 and 16 years of experience) evaluated the presence of BME on DECT mages. Diagnostic accuracy values for diagnosing BME on a per-patient and on a per-partition basis analysis were calculated for DECT images by two readers (R1 and R2, with 16 and 7 years of experience, respectively), using MRI as a gold-standard for diagnosis. Inter-observer agreements were calculated with k-statistics. A p-value of <0.05 was considered as statistically significant. RESULTS: MRI depicted BME in 29/40 patients (72.50%) and in 43/240 partitions (17.91%). The consensus reading by R1 and R2 of DECT images allowed us to achieve 89.7% sensitivity (26/29 patients) and 81.8% specificity (9/11 patients). Regarding the partitions-basis analysis, BME was depicted by DECT in 39/43 partitions (90.69% sensitivity), and ruled out in 189/197 partitions (95.93% specificity). Sensitivity and specificity for the most involved partitions (talar dome) were both 95%. The inter-observer agreement for patients' analysis was substantial (k = 0.697), whereas for the partitions' analysis, it ranged from substantial (k = 0.724) to near perfect (k = 0.950). CONCLUSIONS: DECT can accurately diagnose BME of the ankle in a cohort of non-traumatic patients.

Evaluation of relative wash-in ratio of adrenal lesions at early biphasic CT.

OBJECTIVE: The purpose of this study was to retrospectively evaluate the accuracy of unenhanced attenuation and relative percentage wash-in ratio in early, that is, arterial and portal venous phase, biphasic CT in differentiating adrenal adenomas from metastatic lesions. MATERIALS AND METHODS: One hundred seven adrenal masses in 86 consecutively registered patients (45 men, 41 women; mean age, 56 years) were evaluated. Diagnosis was achieved with percutaneous biopsy (n = 6), surgery (n = 13), and at least 1 year of imaging follow-up (n = 88). Unenhanced, arterial phase, and portal phase scans were obtained. Diameter and absolute attenuation values in each phase of CT were measured in a region of interest covering one to two thirds of a lesion. Relative percentage wash-in ratio was calculated. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in differentiation of adenomas from metastatic lesions were calculated for unenhanced attenuation and for wash-in ratio. A value of p < 0.05 was considered significant. RESULTS: The final diagnosis was metastasis in 51 cases and adenoma in 56 cases. A significant difference was found between benign and malignant lesions in regard to diameter (p = 0.001), unenhanced CT attenuation (p = 0.001), and relative percentage wash-in ratio from the arterial to the portal venous scan (p = 0.014). In the differentiation of benign from malignant lesions, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of unenhanced CT attenuation (at an 11-HU threshold) were 98%, 86%, 86%, 98%, and 92%, and those of relative percentage wash-in ratio from the arterial to the portal venous phase were 94%, 77%, 79%, 93%, and 85%. CONCLUSION: Relative percentage wash-in ratio may help in differentiating adenoma from metastasis and in guiding the decision to perform CT directed at the adrenal glands when unenhanced CT is not available.

Finger fractures imaging: accuracy of cone-beam computed tomography and multislice computed tomography.

OBJECTIVE: To compare the diagnostic accuracy and radiation exposure of cone beam computed tomography (CBCT) and multislice computed tomography (MSCT) in the evaluation of finger fractures. MATERIALS AND METHODS: In a 3-year period, 57 consecutive patients with post-traumatic fractures of the metacarpal-phalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with involvement of the articular surface were studied by means of CBCT and MSCT. Student's t test was used to compare CBCT and MSCT accuracy in evaluating the percentage of joint surface involvement and in detecting bone fragments. The average tissue-absorbed doses of CBCT and MSCT were also compared. A value of p < 0.05 was considered statistically significant. Inter-observer agreement was calculated. RESULTS: In all cases, CBCT allowed the percentage of articular involvement to be correctly depicted compared with MSCT, showing 100% sensitivity and specificity (p < 0.001). A total of 103 bone fragments were depicted on MSCT (mean 3.8 per patient, range 1-23). CBCT indicated 92 out of 103 fragments (89.3%) compared with MSCT (mean diameter of missed fragments 0.9 mm, range 0.6-1.3 mm), with no statistically significant difference between CBCT and MSCT (p < 0.025). Multislice CT radiation exposure was significantly higher than that of CBCT (0.18 mSv vs 0.06 mSv, p < 0.0025). Inter-observer agreement was good (overall κ = 0.89-0.96). CONCLUSIONS: Cone beam CT may be considered a valuable imaging tool in the preoperative assessment of finger fractures, when MSCT is not available.

Contrast-enhanced ultrasonography of the pancreas.

Ultrasound is often the first examination performed in patients with suspicion of pancreatic disease. The introduction of contrast-enhanced ultrasonography (CEUS) has led to great developments in the diagnostic capabilities of ultrasound. Dynamic observation of an enhancement allows a highly sensitive evaluation of any perfusion of the abdominal organs. Study of the pancreas is a new and promising application of CEUS, and can be used to characterize pancreatic lesions visible with conventional ultrasonography (US). This article reviews the clinical and surgical applications of CEUS in different pancreatic diseases and in their management.

Contrast-enhanced sonography of nonfunctioning pancreatic neuroendocrine tumors.

OBJECTIVE: Diagnosis of malignancy and prognostic assessment continue to be problems in the management of nonfunctioning pancreatic endocrine tumors. Histologic examination is the reference standard. The aim of our study was to compare B-mode and contrast-enhanced sonographic findings regarding nonfunctioning pancreatic endocrine tumors. Signs of malignancy, such as Ki67 index and presence of hepatic metastasis, were considered. MATERIALS AND METHODS: We retrospectively reviewed the cases of 38 consecutively registered patients with nonfunctioning pancreatic endocrine tumors evaluated with B-mode and contrast-enhanced sonography and resected. At contrast-enhanced sonography all lesions were divided into hypovascular lesions and isovascular or hypervascular lesions. On the basis of homogeneity of enhancement, lesions were classified as homogeneous and inhomogeneous. During the late phase of contrast enhancement, all solid focal hypoechoic liver lesions detected at contrast-enhanced sonography were considered hepatic metastatic lesions. Among pathologic data, grading, mitotic index, and Ki67 index were evaluated. Spearman's test was used to compare contrast-enhanced sonographic enhancement pattern with pathologic grade. RESULTS: In the arterial phase, 24 of 38 nonfunctioning pancreatic endocrine tumors (63.1%) were hypervascular, seven (18.4%) were isovascular, and seven (18.4%) were hypovascular. Positive correlation was found between contrast-enhanced sonographic findings and Ki67 index (r(s) = 0.62; p < 0.0001). The difference between contrast-enhanced and B-mode sonography in the diagnosis of nonfunctioning pancreatic endocrine tumors was statistically significant (p < 0.05). Use of contrast-enhanced sonography increased diagnostic confidence in the detection of hepatic metastasis. The areas under the receiver operating characteristic curves were 0.916 for B-mode sonography and 1.000 for contrast-enhanced sonography (p < 0.05). There was moderate positive correlation between contrast-enhanced sonographic enhancement pattern and the presence of hepatic metastasis at diagnosis (r(s) = 0.46; p = 0.004) and between Ki67 index and the presence of hepatic metastasis (r(s) = 0.48; p = 0.0022). CONCLUSION: The contrast-enhanced sonographic enhancement pattern of nonfunctioning pancreatic endocrine tumors has a positive correlation with Ki67 index, which is considered the most reliable independent predictor of the presence of malignancy.