{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:47:37Z","timestamp":1760147257834,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,18]],"date-time":"2023-01-18T00:00:00Z","timestamp":1674000000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>The rapid increase in the number of CT acquisitions during the COVID-19 pandemic raised concerns about increased radiation exposure to patients and the resultant radiation-induced health risks. It prompted researchers to explore newer CT techniques like ultra-low dose CT (ULDCT), which could improve patient safety. Our aim was to study the utility of ultra-low dose CT (ULDCT) chest in the evaluation of acute COVID-19 pneumonia with standard-dose CT (SDCT) chest as a reference standard. This was a prospective study approved by the institutional review board. 60 RT-PCR positive COVID-19 patients with valid indication for CT chest underwent SDCT and ULDCT. ULDCT and SDCT were compared in terms of objective (noise and signal-to-noise ratio) and subjective (noise, sharpness, artifacts and diagnostic confidence) image quality, various imaging patterns of COVID-19, CT severity score and effective radiation dose. The sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy of ULDCT for detecting lung lesions were calculated by taking SDCT as a reference standard. The mean age of subjects was 47.2 \u00b1 10.7 years, with 66.67% being men. 90% of ULDCT scans showed no\/minimal noise and sharp images, while 93.33% had image quality of high diagnostic confidence. The major imaging findings detected by SDCT were GGOs (90%), consolidation (76.67%), septal thickening (60%), linear opacities (33.33%), crazy-paving pattern (33.33%), nodules (30%), pleural thickening (30%), lymphadenopathy (30%) and pleural effusion (23.33%). Sensitivity, specificity and diagnostic accuracy of ULDCT for detecting most of the imaging patterns were 100% (p &lt; 0.001); except for GGOs (sensitivity: 92.59%, specificity: 100%, diagnostic accuracy: 93.33%), consolidation (sensitivity: 100%, specificity: 71.43%, diagnostic accuracy: 93.33%) and linear opacity (sensitivity: 90.00%, specificity: 100%, diagnostic accuracy: 96.67%). CT severity score (range: 15\u201325) showed 100% concordance on SDCT and ULDCT, while effective radiation dose was 4.93 \u00b1 1.11 mSv and 0.26 \u00b1 0.024 mSv, respectively. A dose reduction of 94.38 \u00b1 1.7% was achieved with ULDCT. Compared to SDCT, ULDCT chest yielded images of reasonable and comparable diagnostic quality with the advantage of significantly reduced radiation dose; thus, it can be a good alternative to SDCT in the evaluation of COVID-19 pneumonia.<\/jats:p>","DOI":"10.3390\/diagnostics13030351","type":"journal-article","created":{"date-parts":[[2023,1,18]],"date-time":"2023-01-18T03:28:38Z","timestamp":1674012518000},"page":"351","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Ultra-Low Dose CT Chest in Acute COVID-19 Pneumonia: A Pilot Study from India"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4714-6299","authenticated-orcid":false,"given":"Mandeep","family":"Garg","sequence":"first","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5051-2037","authenticated-orcid":false,"given":"Shritik","family":"Devkota","sequence":"additional","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nidhi","family":"Prabhakar","sequence":"additional","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Uma","family":"Debi","sequence":"additional","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maninder","family":"Kaur","sequence":"additional","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Inderpaul S.","family":"Sehgal","sequence":"additional","affiliation":[{"name":"Department of Pulmonary Medicine, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sahajal","family":"Dhooria","sequence":"additional","affiliation":[{"name":"Department of Pulmonary Medicine, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ashish","family":"Bhalla","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Manavjit Singh","family":"Sandhu","sequence":"additional","affiliation":[{"name":"Department of Radiodiagnosis & Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"86","DOI":"10.4103\/ijmr.IJMR_3669_20","article-title":"Computed tomography chest in COVID-19: When & why?","volume":"153","author":"Garg","year":"2021","journal-title":"Indian J. 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