Diagnostic value of computed tomography and magnetic resonance imaging in ovarian malignant mesothelioma.

OBJECTIVE: To investigate the diagnostic value of computed tomography (CT) and magnetic resonance imaging (MRI) in ovarian malignant mesothelioma (OMM). METHODS: The clinical and imaging data of 10 pathologically-confirmed OMM patients were analyzed retrospectively. RESULT: (1) The patients were 27 years to 70 years old, with an average age of 57.2 ± 15.4 years. Seven patients reported abdominal distension and pain, 1 reported lower abdominal discomfort and decreased appetite, and 2 patients had no symptoms. (2) Two cases of localized OMM with incomplete semi-annular "capsule" observed around the localized OMM tumors were reported while 8 cases had diffuse OMM in which the tumor parenchyma showed isointense or slightly hypointense on T1WI, inhomogeneous hyperintense on T2WI, and obviously hyperintense on DWI, with obvious inhomogeneous enhancement after enhancement. Diffuse OMM was not mainly composed of ovarian masses and was mainly characterized by mild ovarian enlargement, nodular and irregular thickening of the peritoneum, cloudy omentum, unclear fat gap, and reticular or irregular thickening, which can fuse into a "cake-shape". (3) All 10 patients underwent surgery, while 9 patients underwent systemic chemotherapy or immunotherapy after surgery. All patients with localized OMM survived. Out of the 8 diffuse-type patients, 5 died, 1 was lost to follow-up, and 2 survived. CONCLUSION: OMM has certain clinical and imaging characteristics. There is no liquefaction, calcification, or partition in the tumor. The ovarian enlargement in the diffuse lesion is not significant. The diffuse thickening of the peritoneum and omentum with early appearance of mural nodules and ascites in the upper abdomen, help the diagnosis of OMM.

Clinical characteristics and high-resolution computed tomography findings of 805 patients with mild or moderate infection from SARS-CoV-2 Omicron subvariant BA.2.

BACKGROUND: COVID-19 is a global pandemic. Currently, the predominant strain is SARS-CoV-2 Omicron subvariant BA.2 in many countries. Understanding its infection characteristics can facilitate clinical management. OBJECTIVES: This study aimed to characterize the clinical, laboratory, and high-resolution computed tomography (HRCT) findings in patients with mild or moderate infection from SARS-CoV-2 Omicron subvariant BA.2. METHODS: We performed a retrospective study on patients infected with SARS-CoV-2 Omicron subvariant BA.2 between April 4th and April 17th, 2022. The clinical characteristics, laboratory features, and HRCT images were reviewed. RESULTS: A total of 805 patients were included (411 males and 394 females, median age 33 years old). The infection was mild, moderate, severe, and asymptomatic in 490 (60.9%), 37 (4.6%), 0 (0.0%), and 278 (34.5%) patients, respectively. Notably, 186 (23.1%), 96 (11.9%), 265 (32.9%), 11 (3.4%), 7 (0.9%), and 398 (49.4%) patients had fever, cough, throat discomfort, stuffy or runny nose, fatigue, and no complaint, respectively. Furthermore, 162 (20.1%), 332 (41.2%), and 289 (35.9%) patients had decreased white blood cell counts, reduced lymphocytes, and elevated C-reactive protein levels, respectively. HRCT revealed pneumonia in 53 (6.6%) patients. The majority of the lung involvements were ground-glass opacity (50, 94.3%) mostly in the subpleural area. The grade of lung injury was mainly mild (90.6%). Short-term follow-ups showed that most patients with pneumonia recovered. CONCLUSION: Most patients with mild or moderate infection from SARS-CoV-2 Omicron subvariant BA.2 were adults, with fever and upper respiratory symptoms as the main clinical presentations. Lower respiratory infection was mild, with ground-glass opacity in the subpleural area as the main finding.

Dynamic Volume Computed Tomography for Characterizing Pulsatile Tinnitus Caused by Sigmoid Sinus Diverticulum with Bone Defects: Clinical Implications.

OBJECTIVE: The objective of this study is to investigate the diagnosis of dynamic volume computed tomography (CT) for pulsatile tinnitus caused by sigmoid sinus diverticulum (SSD) and bone defects. METHODS: Data obtained by dynamic volume CT from 35 patients with SSD were retrospectively collected. Then the ear morphological parameters, including bone defect, transverse sinus stenosis, position of the jugular bulb, jugular bulb diverticulum, defect of the jugular bulb wall, gross venous sinus thrombosis and SSD, and blood perfusion parameters, including cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT), were evaluated and compared between the tinnitus side and the asymptomatic side of the ear. RESULTS: The maximum diameters of the bone defects on the tinnitus side were greater than those on the asymptomatic side (Horizontal 6.36±2.35mm vs. 1.12±0.78mm; Longitudinal 4.87±1.25 vs. 0.88±0.06mm). Dynamic volume CT visually displayed the SSD herniated into the adjacent mastoid via the bone defect. Transverse sinus stenosis, high position of the jugular bulb, jugular bulb diverticulum, defect of the jugular bulb wall, and gross venous sinus thrombosis were present more frequently on the tinnitus side than on the asymptomatic side (P < 0.05). Moreover, CBF, CBV, and MTT were significantly greater on the tinnitus side than on the asymptomatic side (P < 0.05). CONCLUSION: Dynamic volume CT examination is an effective method for the diagnosis of pulsatile tinnitus caused by SSD with bone defects.

Reduction of Metallic Artifacts of the Post-treatment Intracranial Aneurysms: Effects of Single Energy Metal Artifact Reduction Algorithm.

PURPOSE: This study evaluated the quality of computed tomography (CT) and CT angiography images generated using the single-energy metal artifact reduction (SEMAR) algorithm during perfusion examination in patients who had undergone reconstruction with neurosurgical clipping or endovascular coiling for treatment of aneurysms. METHODS: A total of 55 patients with implanted intracranial clips or coils (24 men and 31 women; mean age 60.15 ± 15.86 years) underwent perfusion studies evaluated by CT and CT angiography with a 320-row CT scanner. Images were reconstructed with either the SEMAR algorithm combined with iterative reconstruction (SEMAR group), or by iterative reconstruction only (non-SEMAR group control). The SEMAR and control images were compared for artifacts (index and maximum diameter), image quality, cerebral perfusion parameters, noise (images with the worst artifacts), and contrast-to-noise ratio. The metallic artifacts were visually evaluated by two radiologists using a four-point scale in a double-blinded manner. RESULTS: The noise, artifact diameter, and artifact index of the SEMAR images were significantly lower than that of the control images, and the subjective image quality score and contrast-to-noise ratio were significantly higher (P < 0.01, all). The cerebral perfusion parameters of the SEMAR and control images were comparable (i. e. blood flow, blood volume, and mean transit time). CONCLUSION: For imaging intracranial metallic implants, the SEMAR algorithm produced images with significantly fewer artifacts than the iterative reconstruction alone, with no statistical changes in perfusion parameters. Thus, SEMAR reconstruction can be instrumental in improving CT image quality and may ultimately improve the detection of postoperative complications and patient prognosis.

Molecular Mechanism and Dynamics of S-Deoxyephedrine Moving through Molecular Channels within D3R.

In this article, the trajectories of S-deoxyephedrine (SBD) along molecular channels within the complex protein structure of third dopamine receptor (D3R) are analyzed via molecular dynamic techniques, including potential mean force calculations of umbrella samplings from the 4.5 version of the GROMACS program. Changes in free energy due to the movement of SBD within D3R are determined, and the molecular dynamic mechanisms of SBD transmitting along molecular channels are probed. Molecular simulated results show that the change in free energy is calculated as 171.7 kJ·mol-1 for the transmission of SBD toward the outside of the cell along the y+ axis functional molecular channel and is 275.0 kJ·mol-1 for movement toward the intracellular structure along the y- axis. Within the internal structure of D3R, the changes in free energy are determined to be 103.6, 242.1, 459.7, and 127.8 kJ·mol-1 for transmission of SBD along the x+, x-, z+, and z- axes, respectively, toward the cell bilayer membrane, which indicates that SBD leaves much more easily along the x+ axis through the gap between the TM5 (the fifth transmembrane helix) and TM6 (the sixth transmembrane helix) from the internal structure of D3R. The values of free-energy changes indicate that SBD molecules can clear the protective channel within D3R, which helps dopamine molecules to leave the D3R internal structure along the x+ axis and to prevent them for exerting excessive neurotransmitter function. Therefore, our results suggest that SBD is effective for development as a drug for treating schizophrenia and its pharmacology is closely related to its dynamics and mechanisms within the molecular pathway of dopamine receptors.

Coronary Computed Tomographic Angiography at Low Concentration of Contrast Agent and Low Tube Voltage in Patients with Obesity:: A Feasibility Study.

RATIONALE AND OBJECTIVES: Using lower tube voltage can reduce the exposure to radiation and the dose of contrast agent. However, lower tube voltage is often linked to more noise and poor image quality, which create a need for more effective technology to resolve this problem. To explore the feasibility of coronary computed tomographic angiography (CCTA) in patients with obesity at low tube voltage (100 kV) and low contrast agent concentration (270 mg/mL) using iterative reconstruction. MATERIALS AND METHODS: A total of 48 patients with body mass index greater than 30 kg/m(2) were included and randomly divided into two groups. Group A received a traditional protocol (iopromide 370 mg/mL + 120 kV); group B received a protocol with low tube voltage (100 kV), low contrast agent concentration (270 mg/mL), and iterative reconstruction. The effective dose (ED), average attenuation values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), the figure of merit (FOM), image quality scores, and the total iodine intake were compared. RESULTS: No significant differences in average CT attenuations, SNR, CNR, and subjective scores were noticed between the two groups (P > 0.05), whereas the FOM of group B was significantly higher than that of group A. Effective radiation dose, total iodine, and iodine injection rate in group B were lower than those of group A (P <0.01). CONCLUSIONS: In patients with obesity, isotonic contrast agent with low iodine concentration and low-dose CCTA were feasible. Substantial reduction in radiation dose and the iodine intake could be achieved without compromising the image quality.

Improved Image Quality and Decreased Radiation Dose of Lower Extremity Computed Tomography Angiography Using Low-Tube-Voltage and Adaptive Iterative Reconstruction.

OBJECTIVE: The aim of the study was to investigate the feasibility of low-tube-voltage computed tomography (CT) in combination with 3-dimensional adaptive iterative dose reduction (AIDR-3D) algorithm in lower extremity CT angiography. METHODS: The CT data of the 120-kV group (n = 30) were reconstructed with filtered back projection (FBP) algorithm. The CT data of the 100-kV group (n = 30) were reconstructed with FBP as well as AIDR-3D algorithms. RESULTS: The 100-kV group showed significantly lower dose-length product than the 120-kV group (P < 0.05). In comparison with the 120-kV and FBP protocol, the 100-kV and FBP protocol showed significantly increased vascular density and noise (P < 0.05). However, in the 100-kV group, images reconstructed with AIDR-3D showed significantly lower noise and significantly higher signal-to-noise ratio and contrast-to-noise ratio than FBP (P < 0.05). CONCLUSIONS: Low-tube-voltage (100 kV) 320-row CT in combination with AIDR-3D reconstruction can significantly improve the image quality and reduce radiation dose of lower extremity CT angiography.