Estimating reference values of parenchymal stiffness of normal pancreatic parenchyma by means of point shear wave elastography

Introduction: There are numerous imaging modalities available to describe pancreatic parenchyma. None of the broadly accepted diagnostic methods uses elasticity as an indicator of tissue damage. Aim: The aim of the present study was to establish reference values of parenchymal stiffness of normal pancreatic parenchyma through point shear wave elastography. Materials and methods: The design of the study is prospective single-center cohort study. Sixty patients were included in the study. The ultrasound-based point shear wave elastography (pSWE) imaging technique was applied. The mean and median shear wave velocity values of the pancreatic parenchyma in the head, body and tail were calculated. The influence of certain variables on the shear wave velocity (SWV) values was estimated. Results: A reference range for the entire pancreatic parenchyma of 0.66-1.62 m/s and a mean value of 1.17±0.22 m/s were calculated. Apart from age, none of the evaluated factors proved to have statistically significant influence on the obtained results. A measurement success rate of 94.5%, 97.2%, and 95.8% was established for the head, body, and tail of the pancreas, respectively. Transabdominal pSWE could be utilized for assessment of pancreatic parenchyma with high success rate. A mean value of 1.17 m/s was measured which is consistent with the existing literature on the matter. None of the external factors examined in the study, apart from age, was found to have statistically significant influence on the SWV values. Conclusions: The obtained results suggest that pSWE is a highly objective method for evaluating pancreatic parenchyma. Calculated reference range and mean values could be used in future studies to assess the capabilities of the method for differentiating between normal pancreatic parenchyma and diffuse and focal pancreatic disorders

Factors Affecting Residual Stone Rate, Operative Duration, and Complications in Patients Undergoing Minimally Invasive Percutaneous Nephrolithotomy

Background and objectives: Although minimally invasive percutaneous nephrolithotomy (MPCNL) has demonstrated its efficacy, complete stone clearance was not always achieved, necessitating a second procedure. The purpose of this study was to evaluate factors associated with residual stone rate, operative duration, complications, and hospital stay, in order to develop algorithms for pre-operative prognosis and planning. Materials and Methods: This retrospective study involved 163 Bulgarian patients who underwent MPCNL with Holmium: YAG lithotripsy for the treatment of kidney stones. Patients were considered stone-free if no visible fragments (<3 mm) were found on nephroscopy at the end of the procedure, as well as on postoperative X-ray and abdominal ultrasound on the first postoperative day. Results: Immediate postoperative stone-free outcome was attained for 83.43% of the patients (136/163). Residuals were associated with staghorn stones (OR = 72.48, 95% CI: 5.76 to 91.81); stones in two locations (OR = 21.91, 95% CI: 4.15 to 137.56); larger stone size (OR = 1.12, 95% CI: 1.006 to 1.25); and higher density (OR = 1.03, 95% CI:1.005 to 1.06). The overall categorization accuracy for these factors was 93.80%, AUC = 0.971 (95% CI: 0.932 to 0.991), 89.71% sensitivity, and 96.30% specificity. Predictors of prolonged operative duration were staghorn stones and volume, R-square (adj.) = 39.00%, p < 0.001. Longer hospitalization was predicted for patients with hydronephrosis and staghorn stones, R-square (adj.) = 6.82%, p = 0.003. Post-operative complications were rare, predominantly of Clavien-Dindo Grade 1, and were more frequent in patients with hydronephrosis. We did not find a link between their occurrence and the outcome of MPCNL. Conclusions: Staghorn stones and stones in more than one location showed the strongest association with residual stone rate. Staghorn stones and larger volume were linked with a longer operative duration. Hydronephrosis increased the risk of complications and longer hospitalization

Chest CT diagnostic potential as a tool for early detection of suspected COVID-19 cases in pandemic peaks

Introduction: The emergence of severe acute respiratory syndrome coronavirus disease (COVID-19) in China at the end of 2019 caused a massive global outbreak that has become a major public health issue. Aim: Our aim was to investigate the diagnostic potential of chest CT in screening patients suspected of having COVID-19 in high-prevalence settings. Materials and methods: This is a real-life, prospective, observational study involving 260 patients. All patients received chest CT scan at the emergency department (ED) of Kaspela University Hospital, Plovdiv, Bulgaria and RT-PCR testing for suspected COVID-19 from March 27 to December 31, 2020. COVID-19 likelihood was assessed by assigning each CT scan to a particular category of the COVID-19 Reporting and Data System (CO-RADS). IBM SPSS v. 26 was used to process the data. Results: The male-to-female distribution ratio was 1.4:1 – 150 (57.7%) males vs. 110 (42.3%) females (p=0.014). The median age was 55 yrs (range 46–65 yrs). Discharged patients were 247 (95.0%), the rest died in the COVID-19 intensive care unit. Males were 4.13 times more likely to be diagnosed with CO-RADS≥3 score than females. Increasing age was associated with an increased likelihood of being classified with higher CO-RADS scores. The ROC curves analysis demonstrated that CO-RADS ≥3 was the optimal cutoff for discriminating between a positive and negative PCR (Youden’s index J=0.67), with an AUC of 0.825 (95% CI 0.72-0.93), sensitivity of 91.9% (95% CI 87.7%-95.1%), specificity of 75.0% (95% CI 53.3%-90.2%) and accuracy of 76.4% (95% CI 70.7%-81.4%). Conclusions: The results of this study reveal that a CT examination can provide a quick and accurate diagnosis of patients with suspected COVID-19 infection, whereas the PCR test is time-consuming, and the delay in receiving results can be substantial when the incidence curve begins to grow rapidly

Surveillance Value of Apparent Diffusion Coefficient Maps: Multiparametric MRI in Active Surveillance of Prostate Cancer

Background: This study aims to establish the value of apparent diffusion coefficient maps and other magnetic resonance sequences for active surveillance of prostate cancer. The study included 530 men with an average age of 66, who were under surveillance for prostate cancer. We have used multiparametric magnetic resonance imaging with subsequent transperineal biopsy (TPB) to verify the imaging findings. Results: We have observed a level of agreement of 67.30% between the apparent diffusion coefficient (ADC) maps, other magnetic resonance sequences, and the biopsy results. The sensitivity of the apparent diffusion coefficient is 97.14%, and the specificity is 37.50%. According to our data, apparent diffusion coefficient is the most accurate sequence, followed by diffusion imaging in prostate cancer detection. Conclusions: Based on our findings we advocate that the apparent diffusion coefficient should be included as an essential part of magnetic resonance scanning protocols for prostate cancer in at least bi-parametric settings. The best option will be apparent diffusion coefficient combined with diffusion imaging and T2 sequences. Further large-scale prospective controlled studies are required to define the precise role of multiparametric and bi-parametric magnetic resonance in the active surveillance of prostate cancer

Point Shear Wave Elastography and 2-Dimensional Shear Wave Elastography as a Non-Invasive Method in Differentiating Benign from Malignant Liver Lesions

Non-invasive, ultrasound-based methods for visualizing and measuring tissue elasticity are becoming more and more common in routine daily practice. An accurate diagnosis of malignant and benign tumors is essential for determining the appropriate treatment. Despite the wide use of imaging techniques, the investigation for assessing the elasticity of focal liver lesions and their differentiating is still continuing. Aim: To investigate the value of point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) for the differential diagnosis of benign and malignant focal liver lesions. Materials and Methods: A total of 125 adult patients were included from the Clinic of Gastroenterology of University Hospital Kaspela, Plovdiv city, Bulgaria, in the period from January 2021 to July 2022. Participants were divided into two groups—with benign (hemangiomas) and malignant focal liver lesions (hepatocellular carcinoma). The group with benign lesions included 63 patients and the group with malignant focal liver lesions (FLLs)—62 patients. Point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) integrated in the same ultrasound machine (Esaote MyLab™ 9Exp) were performed for each lesion. Results: Malignant FLLs have significantly higher stiffness in both pSWE (2.52–4.32 m/s, 90% CI: 2.37 to 2.68, 90% CI: 4.19 to 4.55) and 2d-SWE (2.52–4.43 m/s, 90% CI: 2.31 to 2.65, 90% CI: 4.27 to 4.61). Conclusion: 2D-SWE and pSWE could provide complementary data about FLLs. They enable us to conveniently and easily obtain accurate stiffness information of FLLs

Comparison of Point Shear Wave Elastography and 2-Dimensional Shear Wave Elastography Values of Liver Metastases from Colorectal Cancer

Nowadays ultrasound-based non-invasive techniques for the evaluation of tissue elasticity are becoming increasingly popular. A key determinant for the adequate treatment of focal liver lesions is on establishment of accurate diagnosis. Contemporary imaging modalities, particularly ultrasonographic, are widely accepted for assessing the elasticity of focal liver lesions but the investigation of their accuracy and differentiation potential is still ongoing. Aim: To compare the values of point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) for liver metastases from colorectal cancer. Materials and Methods: A total of 31 adult patients with liver metastases from colorectal cancer (CRC) were included from the Department of Gastroenterology of University Hospital Kaspela, Plovdiv, Bulgaria, in the period June 2022 to November 2022. The men/women ratio of the participants was respectively 11 women and 20 men. For all of them point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) were performed to evaluate the stiffness of liver metastases, by measuring the shear wave velocity (SWV) in a region of interest (ROI). Prior histological confirmation of colorectal cancer through diagnostic lower endoscopy was a prerequisite for inclusion in the study. Contrast-enhanced computer tomography (CECT) was used as a reference imaging modality to confirm the presence of lesions in the liver. All the images were evaluated by a radiologist with long-standing experience in liver imaging. Results: For point shear wave elastography (pSWE), the lower limit was found to be 1.80 m/s (90% CI: 1.39 to 2.32) and the upper limit was 4.21 m/s (90% CI: 3.69 to 4.60). For two-dimensional shear wave elastography (2D-SWE), the lower limit was determined to be 1.87 m/s (90% CI: 1.54 to 2.25) and the upper limit was 3.65 m/s (90% CI: 3.26 to 3.97). Conclusions: Point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) could bring additional information about the stiffness of liver metastases from colorectal cancer but they are not to be considered a method to substitute biopsy of colorectal cancer during lower endoscopy