Azmera GissilaAmir AlwanYimaj AbduHawi Farris2026-06-222026-06-222025-02-07https://etd.aau.edu.et/handle/123456789/8304Background: The diameter of the thoracic aorta (TA) is a crucial factor in assessing cardiovas cular health, as deviations from normal ranges can indicate underlying pathological conditions, such as aortic dilatation and aneurysm. Although substantial research has been conducted worldwide to determine normative data for TA diameters, there is a notable lack of such data for Ethiopian populations. The accuracy, speed, reproducibility, simplicity, and 3D capability of Computed Tomography (CT) have made it the gold standard for evaluating the TA. Objective: To assess the diameter of the TA at multiple anatomical levels and identify factors correlated with its diameter in adult Ethiopians who visited the Radiology Department at Tikur Anbessa Specialized Hospital between September 1 and November 30, 2024. Methodology: An institution-based prospective cross-sectional study was conducted using a consecutive sampling method. Data were collected from consecutive eligible adults who came for contrast-enhanced CT scans during the study period, using interviewer-administered struc tured questionnaires. The data were cleaned and analyzed using SPSS version 27. Descriptive statistics, including frequency, percentages, means, and ratios, as well as the independent Stu dent's t-test, Mann-Whitney U test, and Pearson correlation, were used for statistical analysis. The p-value threshold was set at 0.05. Results: A total of 386 study participants were included, of whom 244 (63.2%) were females and 142 (36.8%) were males. The mean age was 46.04 ± 15.39 years, with a range of 18 to 86 years. The thoracic aorta showed smooth tapering from the ascending to the descending aorta. The diameters (mean ± SD) at the level of the sinus of Valsalva, STJ, mid-ATA, distal ATA, arch, proximal DTA, mid-DTA, and distal DTA were 35.29 ± 2.60 mm, 27.10 ± 2.71 mm, 33.72 ± 3.35 mm, 32.35 ± 3.29 mm, 29.42 ± 2.82 mm, 26.66 ± 2.89 mm, 23.42 ± 2.49 mm, and 21.80 ± 2.40 mm, respectively. The thoracic aorta diameter at all levels had a statistically significant correlation with age, weight, BSA, and hypertension (p<0.05). Conclusion: This study evaluated the mean diameter of the thoracic aorta at various levels in Ethiopian adults at TASH, providing a normal reference range. It found a statistically significant association of the TA diameter at all levels with age, weight, BSA, and hypertension.enThoracic aorta diameterassociation of TA diameter with anthropometric variablesand Computed Tomography.Thesis