Ultrasound-Tomographic Image Fusion - A Novel Tool for Follow up After Acute Complicated Appendicitis.

BACKGROUND: Computerized tomography (CT) is an integral part of the follow-up and decision-making process in complicated acute appendicitis (AA) treated non-operatively. However, repeated CT scans are costly and cause radiation exposure. Ultrasound-tomographic image fusion is a novel tool that integrates CT images to an Ultrasound (US) machine, thus allowing accurate assessment of the healing process compared to CT on presentation. In this study, we aimed to assess the feasibility of US-CT fusion as part of the management of appendicitis. MATERIALS AND METHODS: We retrospectively collected data of consecutive patients with complicated AA managed non-operatively and followed up with US Fusion for clinical decision-making. Patients demographics, clinical data, and follow-up outcomes were extracted and analyzed. RESULTS: Overall, 19 patients were included. An index Fusion US was conducted in 13 patients (68.4%) during admission, while the rest were performed as part of an ambulatory follow-up. Nine patients (47.3%) had more than 1 US Fusion performed as part of their follow-up, and 3 patients underwent a third US Fusion. Eventually, 5 patients (26.3%) underwent elective interval appendectomy based on the outcomes of the US Fusion, due to a non-resolution of imaging findings and ongoing symptoms. In 10 patients (52.6%), there was no evidence of an abscess in the repeated US Fusion, while in 3 patients (15.8%), it significantly diminished to less than 1 cm in diameter. CONCLUSION: Ultrasound-tomographic image fusion is feasible and can play a significant role in the decision-making process for the management of complicated AA.

Noninvasive Assessment of Fibrosis Regression after Direct-acting Antiviral Treatment in Hepatitis C Virus Patients.

BACKGROUND: New direct acting antiviral agent (DAA) therapies are associated with a high sustained virological response rate (SVR) in hepatitis C virus (HCV) patients. The understanding of the impact of SVR on fibrosis stage is limited. OBJECTIVES: To determine the effect of treatment with the DAAs on long-term liver fibrosis stages, as determined by shear-wave elastography (SWE) or FibroTest. METHODS: Fibrosis stage was determined at baseline and at 6-month intervals after end of treatment (EOT), using two-dimensional SWE or FibroTest©; APRI and FIB-4 scores. RESULTS: The study comprised 133 SVR12 patients. After a median follow-up of 15 months (range 6-33), liver fibrosis stage decreased by at least 1 stage in 75/133 patients (56%). Cirrhosis reversal was observed in 24/82 (29%). Repeated median liver stiffness SWE values in cirrhotic patients were 15.1 kPa at baseline (range 10.5-100), 13.4 kPa (range 5.5-51) at 6 months, and 11.4 kPa (range 6.1-35.8) at 12 months after EOT, P = 0.01. During the second year after EOT, no statistically significant differences in liver fibrosis stage in 12, 18, and 24 months were found. Splenomegaly was the only significant negative predictor of liver fibrosis regression during all time points of repetitive noninvasive assessment. CONCLUSIONS: Following successful DAA treatment, the majority of our HCV patients with advanced fibrosis demonstrated significant improvement, as assessed by non-invasive methods. Advanced fibrosis stage was a negative predictor of fibrosis regression. Longer follow-up periods are required to further establish the impact of DAAs treatment in HCV patients with advanced fibrosis.

The impact of bariatric surgery on nonalcoholic fatty liver disease as measured using non-invasive tests.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is common in bariatric surgery candidates. We evaluated the effect of sleeve gastrectomy (SG) on NAFLD using validated non-invasive measures. METHODS: Patients with morbid obesity and NAFLD, planned for SG, were evaluated before and after surgery. Data collected included anthropometrics, biochemistry, adiponectin, SteatoTest™, NashTest™, FibroTest™, OWLiver® test and real-time ShearWave™ elastography (SWE). RESULTS: Twenty-six subjects were included in the study, mean age 44.1 ± 4.8 years, 69.2% males. One year following SG, body mass index decreased significantly from 41.7 ± 4.8 kg/m2 to 29.6 ± 4.5 kg/m2. Concomitantly, significant improvements in triglycerides, ALT, diabetes markers and adiponectin were observed. Mean steatosis, as measured by SteatoTest™, was significantly improved. Steatohepatitis score measured by NashTest™ and OWLiver® significantly decreased. Mean fibrosis, as measured by SWE liver stiffness and FibroTest™, did not change over time. CONCLUSION: Steatosis and steatohepatitis are significantly improved by SG as measured by non-invasive measures.

Incidence and risk factors of pneumothorax following pre-procedural ultrasound-guided thoracentesis.

BACKGROUND: Data regarding the incidence and risk factors of pneumothorax following pre-procedural ultrasound (US)-guided thoracentesis is scarce. We aimed to evaluate the incidence and risk factors of pneumothorax following pre-procedural US-guided thoracentesis in a tertiary medical center. METHODS: Retrospective analysis of patients who underwent pre-procedural US-guided thoracentesis in Sheba Medical Center between January 2016 and December 2018. Data collected included incidence of pneumothorax following thoracentesis, baseline clinical and demographic characteristics, and thoracentesis-associated factors. Outcomes evaluated included length of hospital stay, mortality, chest tube insertion and intensive care unit admission. RESULTS: A total of 550 patients with pleural effusions underwent pre-procedural US-guided thoracentesis. Sixty-six (12%) of them developed pneumothorax. Compared to patients who did not develop pneumothorax, those who developed pneumothorax had a higher rate of congestive heart failure (32.2% vs. 47%, P=0.026), a smaller depth of pleural fluid marking (3.4 vs. 3.2 cm, P=0.024), a larger amount of pleural fluid drained (1,093 vs. 903.5 mL, P=0.01), and were more likely to undergo bilateral procedures (7.6% vs. 2.3%, P=0.044). In the multivariate regression analysis, volume of pleural fluid drained was significantly associated with the development of pneumothorax (OR, 1.001, 95% CI, 1-1.001; P=0.042). CONCLUSIONS: The incidence of pneumothorax following pre-procedural US-guided thoracentesis was relatively high in the present study. The amount of pleural fluid drained was the main factor associated with the risk of developing pneumothorax in these cases.

The Diffusion Tensor Imaging Properties of the Normal Testicles at 3 Tesla Magnetic Resonance Imaging.

RATIONALE AND OBJECTIVES: The testicles are structured in a well-defined microtubular network formation, which is expected to be reflected in high anisotropic diffusivity. However, preliminary studies reported on low values of fractional-anisotropy (FA) in the normal testicles. Our aim was to design and apply a diffusion-tensor imaging (DTI) protocol in order to elucidate the diffusivity properties of the testicles and their determining factors. MATERIALS AND METHODS: 16 healthy volunteers were prospectively scanned at 3T. The protocol included T2-weighted and DTI sequences, the latter using 24 directional diffusion gradients and 3 b-values (0, 100, and 700 s/mm2) that were separated for analysis based on the reference b-value of 0 or 100 s/mm2. Image processing of the two DTI datasets yielded the diffusion vector maps and parametric maps of their corresponding principal diffusion coefficients λ1, λ2, λ3, mean diffusivity and FA. RESULTS: The results demonstrated the feasibility of DTI to provide parametric maps of the testicles. The diffusion tensor parameters obtained using the pair of 0 and 700 s/mm2 b-values, exhibited relatively low diffusivity, with mean λ1 values of 1.36 ± 0.21 × 10-3 mm2/s and low anisotropy, with mean FA values of 0.13 ± 0.05. Analysis of DTI using the 100 and 700 s/mm2 b-values yielded a slight decrease in the diffusivity of 4%-5%, whereas FA remained similar. CONCLUSION: The diffusivity of the normal testicles is relatively slow, closed-to isotropic and hardly affected by the low b-values regime exclusion. Thus, DTI parameters of the normal testicles are neither dictated by the underlying architectural anisotropy nor microperfusion effects.

The Role of Liver Segment-to-Spleen Volume Ratio in the Staging of Hepatic Fibrosis in Patients with Hepatitis C Virus Infection.

BACKGROUND: Accurate assessment of liver fibrosis is crucial for the management of patients with hepatitis C virus (HCV) infection. OBJECTIVES: To evaluate the performance of liver segment-to-spleen volume ratio in predicting the severity of liver fibrosis. METHODS: Sixty-four consecutive HCV patients were enrolled in this retrospective study. All patients underwent contrast-enhanced computed tomography (CT) and were divided into three groups based on their hepatic fibrosis stage evaluated by shear-wave elastography (SWE): non-advanced (F0-F1, n=29), advanced (F2, n=19) and severe fibrosis (F3-F4, n=16). Using semi-automated liver segmentation software, we calculated the following liver segments and spleen volumes for each participant: total liver volume (TLV), caudate lobe (CV), left lateral segment (LLV), left medial segment (LMV), right lobe (RV) and spleen (SV), a well as their ratios: CV/SV, RV/SV, LLV/SV, LMV/SV and TLV/SV. RESULTS: RV/SV was found to discriminate between patients with non-advanced and advanced fibrosis (P = 0.001), whereas SV, CV, RV, TLV/SV, LMV/SV and RV/SV discriminated between patients with advanced and severe fibrosis (P < 0.05). RV/SV ≤ 3.6 and RV ≤ 2.9 were identified as the best cutoff values to differentiate non-advanced from advanced fibrosis and advanced from severe fibrosis with sensitivities of 72.2% and 92.7%, specificities of 72.7% and 77.8%, and with an area under the receiver operating characteristic (ROC) curve of 0.797 and 0.847, respectively (P ≤ 0.002). CONCLUSIONS: RV/SV may be used for the assessment and monitoring of liver fibrosis in HCV patients prior to the administration of antiviral therapy, considering SWE as the reference method.

The Yield of Abdominal Ultrasound in the Evaluation of Elevated Liver Enzymes during the Second and the Third Trimester of Pregnancy.

AIMS: To determine the clinical yield of abdominal ultrasound in the evaluation of elevated liver enzymes (ELEs) in the second and the third trimester of pregnancy. METHODS: A retrospective cohort study including all pregnant women admitted to a single tertiary care center was conducted between April 2011 and January 2015 with ELE. Inclusion criteria included gestational age above 24 weeks and ELEs, abdominal ultrasound report, and live fetus. Exclusion criteria included known maternal liver disease, structural or chromosomal fetal anomalies, and positive serology for viral hepatitis. All patients underwent abdominal ultrasound. A significant finding of this study led to a change in treatment. RESULTS: One hundred and twenty patients (41.8%) met inclusion criteria: 93 (77.5%) had a normal scan and 27 (22.5%) had abnormal findings. Significant ultrasound findings were found only in 2 (1.6%) patients: gallstones in the common bile duct and suspected autoimmune hepatitis. There were no significant differences between patients with and without ultrasound findings in the rate of cholestasis of pregnancy, preeclampsia, chronic hypertension, and gestation diabetes. CONCLUSION: Abdominal ultrasound examination in this population has a low clinical yield. The decision to perform an abdominal ultrasound must be individualized based on the obstetric history, clinical findings, and the level of liver enzymes.

Torsed and Nontorsed Inguinal Undescended Testis: Comparison of Computed Tomography Findings.

OBJECTIVE: The aim of this study was to compare the computed tomography imaging features of a torsed inguinal testis with nontorsed inguinal testes. METHODS: Computed tomography scans of patients with undescended testes were retrospectively collected (2011-2016). Imaging features of nontorsed undescended testis were compared with a case of an inguinal torsed testis. Observations included location of the undescended testis, size (length × width) and texture of each testis, peritesticular findings, position of testicular vessels, and enhancement patterns. RESULTS: Twelve nontorsed inguinal undescended testes were compared with 1 torsed undescended testicle. Torsed testis was larger than nontorsed (44 × 27 mm vs 32.9 ± 6.1 × 22.9 ± 4.9 mm), surrounded by fat stranding and fluid, with heterogeneous texture, enhancement of its outer layers, and an upward kink of its vessels. CONCLUSIONS: Because torsed undescended testis can mimic a groin abscess and because torsion is a medical emergency, radiologists should be aware of this entity and its distinguishing imaging features. Color Doppler examination can ascertain absence/reduction of blood flow.

Budd-Chiari syndrome in very young adult patients with polycythemia vera: report of case series with good outcome with direct thrombin inhibitor treatment.

Polycythemia vera is a Philadelphia chromosome-negative myeloproliferative disorder with incidence of 1% under the age of 25. The Budd-Chiari syndrome (BCS) is a well known complication of polycythemia vera even in children, and characterized by occlusion of hepatic outflow. A computerized archive search of medical records at Sheba Medical Center of the past three decades of patients with polycythemia vera and BCS under the age of 25 years was performed. A work-up for JAK2 V617F mutation and thrombophilia was done. Medical charts and imaging tests were carefully reviewed. Three patients under the age of 22 were finally recruited. Two of those were found in life-threatening condition and improved clinically following treatment with bivalirudin, a direct thrombin inhibitor. It is conceivable that bivalirudin contributed to a favorable outcome of those patients in comparison to historical outcome previously reported. In conclusion, polycythemia vera in the young is not a mild disease since BCS, which is one of its complication, can be fatal even in those age group unrelated to the presence of hereditary thrombophilia. Once BCS occurs, we would suggest giving a trial with bivalirudin before an invasive procedure is planned.