BACKGROUND: The thymus changes with age. Its shape and the proportion of solid tissue and fat vary between individuals, yet there is no comprehensive work describing the size and morphology of the normal thymus on CT. As a result, many adults with some preserved soft tissue in the thymus may undergo extensive work-up to exclude mediastinal tumor. Our aim was to quantify CT characteristics of the normal thymus in an adult population. METHODS: CT chest scans of 194 trauma patients aged 14-78 years (mean 52.6 years), were retrospectively reviewed. The density, volume, shape and predominant side of the thymus were recorded for 56 patients in whom some solid tissue was preserved. Statistical analysis of these characteristics according to the patient age and gender was performed. RESULTS: Thymic density and volume decreased progressively with age. No solid tissue component was seen in the thymus in patients older than 54 years. In the majority of patients, the thymus had an arrowhead shape, with middle position. However, great variability in thymic shape and border were noted. There was a highly significant relationship between density and patient age (p<0.0001). CONCLUSION: We hope that our work will help in the definition of normal thymic CT parameters in adults, help to prevent unnecessary and expensive imaging procedures, and reduce patient exposure to ionizing radiation.
BACKGROUND: The thymus changes with age. Its shape and the proportion of solid tissue and fat vary between individuals, yet there is no comprehensive work describing the size and morphology of the normal thymus on CT. As a result, many adults with some preserved soft tissue in the thymus may undergo extensive work-up to exclude mediastinal tumor. Our aim was to quantify CT characteristics of the normal thymus in an adult population. METHODS: CT chest scans of 194 traumapatients aged 14-78 years (mean 52.6 years), were retrospectively reviewed. The density, volume, shape and predominant side of the thymus were recorded for 56 patients in whom some solid tissue was preserved. Statistical analysis of these characteristics according to the patient age and gender was performed. RESULTS: Thymic density and volume decreased progressively with age. No solid tissue component was seen in the thymus in patients older than 54 years. In the majority of patients, the thymus had an arrowhead shape, with middle position. However, great variability in thymic shape and border were noted. There was a highly significant relationship between density and patient age (p<0.0001). CONCLUSION: We hope that our work will help in the definition of normal thymic CT parameters in adults, help to prevent unnecessary and expensive imaging procedures, and reduce patient exposure to ionizing radiation.
Authors: Tetsuro Araki; Mizuki Nishino; Wei Gao; Josée Dupuis; Gary M Hunninghake; Takamichi Murakami; George R Washko; George T O'Connor; Hiroto Hatabu Journal: Eur Radiol Date: 2015-04-30 Impact factor: 5.315
Authors: Kate A Harrington; David S Kennedy; Bobby Tang; Conor Hickie; Emma Phelan; William Torreggiani; Darragh Halpenny Journal: Br J Radiol Date: 2018-03-07 Impact factor: 3.039
Authors: Kenneth W Fishbein; Sokratis K Makrogiannis; Vanessa A Lukas; Marilyn Okine; Ramona Ramachandran; Luigi Ferrucci; Josephine M Egan; Chee W Chia; Richard G Spencer Journal: Magn Reson Imaging Date: 2018-03-29 Impact factor: 2.546
Authors: Gregory M Fahy; Robert T Brooke; James P Watson; Zinaida Good; Shreyas S Vasanawala; Holden Maecker; Michael D Leipold; David T S Lin; Michael S Kobor; Steve Horvath Journal: Aging Cell Date: 2019-09-08 Impact factor: 9.304