Aquilion 64 slice ct

Chest CT scans were performed at the time of hospital admission and during the hospital stay, with a 64-slice scanner (Toshiba Aquilion 64-Slice CT, Tokyo, Japan) dedicated to COVID-19 patients. CT examinations were performed with the patient in the supine position using a standard dose protocol, without contrast intravenous injection. The scanning range was from the apex to the base of the lungs. The tube voltage and the current tube were 120 kV and 100–200 mA, respectively. All images were obtained with a standard dose scanning protocol, reconstructed at 1.0 mm slice thickness, with 1 mm increment, 512 × 512 mm. Images were reconstructed with a sharp reconstruction kernel for parenchyma (FC13 on Toshiba). The lung window setting was at a window level of −600 Hounsfield units (HU) and window width of 1600 HU.

A diagnosis of dementia was always supported by neuroimaging evidence. All patients underwent a brain non-contrast CT. The instrument used was a Toshiba Aquilion 64-slice CT (Manufacture product code: CTSCAN74442-3493, Japan). The slice thickness was 10 mm. Radiograms were evaluated by trained radiologists who were not informed about the clinical characteristics of the patients. In particular, by CT scans, the presence of multiple cortical/subcortical infarcts or an infarct in a strategic area such as the thalamus or temporal lobe and/or lesions of the white matter indicated probable VaD; the absence of the above-mentioned cerebrovascular lesions indicated AD. Using the choroidal fissure width, temporal horn, and hippocampal formation height, atrophy was assessed in five MTA degrees (0 to 4) [12 (link)]. A score of 0 indicated no atrophy, a score of 1 indicated an enlargement of the choroidal fissure, a score of 2 included a further enlargement of the temporal horn of the lateral ventricle, and the height of hippocampal formation was slightly reduced, a score of 3 included a moderate volume loss of the hippocampal formation, and a score of 4 indicated an increase in all of these outcomes in the final phase.

All imaging studies were performed on a Toshiba Aquilion 64 Slice CT, and the scanning protocol at the time included both unenhanced and enhanced scans. Both images were collected for evaluation. Parameters varied among the unenhanced and enhanced examinations, with a slice thickness ranging from 3 to 5 mm. All MDCT images were reviewed by two experienced radiologists (with 3 and 15 years of experience in reading CTPA, respectively) who were blinded to the patients’ medical history and examination and laboratory findings. The radiologists reviewed the records independently. When their independent observations did not agree, they attempted to achieve a consensus. If no consensus was achieved the patient was excluded. Only non-contrast images were reviewed by the radiologists to avoid possible misleading due to contrast-enhanced results. Three important radiologic features on unenhanced MDCT images were chosen to compare with the Wells score: High-attenuation emboli in pulmonary artery (PA), main PA dilatation > 33.2 mm, and peripheral wedge-shaped consolidation. Again, only when all features were agreed upon by the two radiologists was a patient included in the study.