[The role of thoracic CT scan, a triage tool for suspected COVID-19 cases]. / Place du scanner thoracique, outil de triage des cas suspects de Covid-19.

The SARS-Cov-2 pandemic took health care players across the world by surprise, including caregivers, managers and logisticians. In the absence of a vaccine or a specific therapy, detecting the disease at an early stage and isolating confirmed cases from the rest of the healthy population was soon considered to be essential. The RT-PCR technique was the gold standard method for testing for infection with the virus. It has high specificity but moderate sensitivity. It was difficult to access it during the first weeks of the pandemic. On the basis of the observations of the Chinese and Italian scientific community in particular, the recommendation was to combine use of the RT-PCR with a low-dose thoracic CT scan. In the absence of easy access to the RT-PCR, the use of the lung CT scan for a rapid triage of patients within emergency departments proved effective.

Gastric Wall Fatty Infiltration in Patients Without Overt Gastrointestinal Disease.

OBJECTIVE: The purpose of this study was to evaluate the frequency of gastric wall fatty infiltration in patients without overt gastrointestinal disease. MATERIALS AND METHODS: A retrospective study included patients who underwent unenhanced MDCT for renal colic. Two radiologists reviewed all of the images and evaluated for the presence of gastric wall fatty infiltration. The following patient characteristics were also recorded: sex, age, body mass index, total and visceral fat area, and presence of colic or ileal fat halo sign, or hepatic steatosis. A t test and Fisher test were used to compare the results between patients with and patients without gastric wall fatty infiltration. RESULTS: Gastric wall fatty infiltration was present in 25 of 120 (21%) patients in the study. Mean age, weight, body mass index, visceral and total fat areas, proportion of hepatic steatosis, number of men, and frequency of the presence of colic and ileal fat halo signs were significantly higher among patients with gastric wall fatty infiltration than in those without infiltration. CONCLUSION: Gastric wall fatty infiltration was significantly more frequent in men older than 45 years and patients with a body mass index greater than 25. It may represent a normal finding, but its relation to other pathologic conditions related to obesity remains to be explored.

Low-dose CT with automatic tube current modulation, adaptive statistical iterative reconstruction, and low tube voltage for the diagnosis of renal colic: impact of body mass index.

OBJECTIVE: The objective of our study was to evaluate the impact of body mass index (BMI) on dose, diagnostic performance, and image quality of a low-dose CT examination for renal colic. MATERIALS AND METHODS: This retrospective study included all patients who underwent a low-dose CT examination for renal colic performed during the year 2012 with automatic tube current modulation, adaptive statistical iterative reconstruction, and a low tube voltage (kV). Three readers independently reviewed all images for the presence of renal colic and evaluated diagnostic confidence and image quality. The results and doses were compared among patients grouped by body mass index (BMI) and between patients with a BMI<25 and those with a BMI≥25. RESULTS: Eighty-six patients were included in the study: 39 patients had a BMI<25 and 47 had a BMI≥25. No statistically significant difference was found between the accuracy rates for the diagnosis of renal colic when the rates of the three independent readers were averaged for both BMI groups (95.7% vs 96.4%, respectively; p=0.83). Image quality and diagnostic confidence scores were significantly better for patients with a BMI≥25 than for patients with a BMI<25 (mean image quality score, 3.7 vs 3.4, p<0.001; mean diagnostic confidence score, 2.8 vs 2.5, p<0.001). The mean radiation dose for patients with a BMI<25 was 2.4 mGy compared with 3.7 mGy for patients with a BMI≥25 (p<0.001). CONCLUSION: The diagnostic performance of our low-dose CT protocol for renal colic was excellent for all patients, and image quality and diagnostic confidence were significantly better for patients with a BMI≥25. However, our protocol also required exposure to a greater dose of radiation for these overweight and obese patients.