Response letter to "Acute cholangitis: Does malignant biliary obstruction vs choledocholithiasis etiology change the outcomes?" with imaging aspects.

Radiological imaging findings may contribute to the differentiation of malignant biliary obstruction from choledocholithiasis in the etiology of acute cholangitis.

Quadruple-Rule-Out Computed Tomography Angiography (QRO-CT): A Novel Dual-Energy Computed Tomography Technique for the Diagnostic Work-Up of Acute Chest Pain.

BACKGROUND: Computerized tomography (CT) has been increasingly utilized in the differential diagnosis of acute chest pain. Combining the triple rule out CT angiography (TRO-CT) approach with dual-energy CT (DECT) can enhance the diagnostic capability by identifying myocardial perfusion deficiencies. This combination can yield a quadruple-rule-out computed tomography angiography (QRO-CT) technique. The aim of this study is to determine the efficacy of the QRO-CT. METHODS: Intraluminal diseases and abnormalities in the main coronary arteries and branches were investigated. The myocardial dark spots on the color-coded iodine map were identified as perfusion deficiencies. Pulmonary arteries and aorta were also evaluated. RESULTS: The study population consisted of 211 patients. The sensitivity, specificity, and positive and negative predictive values of QRO-CT for pulmonary embolism were 93.5%, 100%, 100%, and 95.3%, respectively. For obstructive coronary artery disease, the values were 96.1%, 93.4%, 89.2%, and 97.7%, respectively. For myocarditis, the values were 69.2%, 100%, 100%, and 93.6%, respectively. CONCLUSIONS: the QRO-CT method may successfully evaluate myocardial perfusion deficits, hence expanding the differential diagnosis capabilities of the standard TRO-CT method for myocarditis. It can provide useful information on myocardial perfusion, which may influence the choice to perform invasive catheterization in cases of coronary artery obstruction.

There Is No Relation between Epitympanic Recess Volume and Chronic Otitis Media.

BACKGROUND: Chronic otitis media is recurrent infection of the middle ear and mastoid air cells in the setting of perforation of the tympanic membrane. Risk factors for chronic otitis media include predisposing characteristics such as gender, allergies, Eustachian tube dysfunction, history of acute otitis media, and upper respiratory tract infection. The purpose of this study was to evaluate the potential relationship between chronic otitis media and epitympanic recess volume. MATERIALS AND METHODS: A total of 197 patients with chronic otitis media had their epitympanic recess volume compared to the epitympanic volume of 99 healthy controls. The epitympanic recess volume was measured via the 3D volumetric measurement tool of the local PACS. Epitympanic recess volume measurement was performed using axial sections in a plane starting from the level of the malleus head-anvil body in the craniocaudal direction to the tegmen tympanum. RESULTS: It was shown that patients with bilateral involvement had an epitympanic recess volume of 75.00 mm3, compared to 72.30 mm3 in those with unilateral chronic otitis media. The healthy control group's median value for the epitympanic recess was 74.73 mm3. CONCLUSIONS: Epitympanic volume values did not differ substantially between patients with chronic otitis media and healthy persons, and epitympanic volume was not recognized as a predisposing factor (p = 0.686).

Virtual non-enhanced dual-energy computed tomography reconstruction: a candidate to replace true non-enhanced computed tomography scans in the setting of suspected liver alveolar echinococcosis.

PURPOSE: When a suspected hepatic alveolar echinococcosis (AE) lesion is detected on a contrast enhanced computed tomography (CT) scan, an additional triphasic or non-enhanced CT scan is required to determine the presence of calcification and enhancement. As a result, imaging costs and exposure to ionizing radiation will increase. We can create a non-enhanced series from routine contrast-enhanced images using dual-energy CT (DECT) and virtual non-enhanced (VNE) images. This study's objective is to assess virtual non-enhanced DECT reconstruction as a potential diagnostic tool for hepatic AE. METHODS: Triphasic CT scans and a routine dual energy venous phase were acquired using a third-generation DECT system. A commercially available software package was used to generate VNE images. Individual evaluations were conducted by two radiologists. RESULTS: The study population consisted of 100 patients (30 AE, 70 other solid liver masses). All AE cases were diagnosed [no false positives/negatives, 95% confidence interval (CI) sensitivity: 91.3%-100%; 95% CI specificity: 95.3%-100%]. Interrater agreement was k: 0.79. In total, 33 (33.00%) of the patients had AE, which was detected using both true non-enhanced (TNE) and VNE images. The mean dose-length product of a standard triphasic CT was significantly higher than biphasic dual-energy VNE images. CONCLUSION: In terms of diagnostic confidence, VNE images are comparable with actual non-enhanced imaging when evaluating hepatic AE. Further, VNE images could replace TNE images with a substantial radiation dose reduction. Advances in knowledge: hepatic cystic echinococcosis and AE are serious and severe diseases with high fatality rates and a poor prognosis if managed incorrectly, especially AE. Moreover, VNE images produce equal diagnostic confidence to TNE images for assessing liver AE, with a significant reduction in radiation dose.