Computer tomography-based assessment of perivascular adipose tissue in patients with abdominal aortic aneurysms

• Published in: Scientific reports 2024-09, Vol.14 (1), p.20512-9, Article 20512
• Main Authors: Ginzburg, Daniel, Nowak, Sebastian, Attenberger, Ulrike, Luetkens, Julian, Sprinkart, Alois Martin, Kuetting, Daniel
• Format: Article
• Language: English
• Subjects: 692/700/1421/1846; 692/700/1421/1846/2771; Abdomen; Adipose tissue; Adipose Tissue - diagnostic imaging; Adipose Tissue - pathology; Aged; Aged, 80 and over; Aorta; Aorta, Abdominal - diagnostic imaging; Aorta, Abdominal - pathology; Aortic Aneurysm, Abdominal - diagnostic imaging; Aortic Aneurysm, Abdominal - pathology; Aortic aneurysms; Artificial intelligence; Body fat; Case-Control Studies; Computed tomography; Coronary vessels; Female; Humanities and Social Sciences; Humans; Inflammation; Male; Middle Aged; multidisciplinary; Retrospective Studies; Science; Science (multidisciplinary); Tomography, X-Ray Computed - methods
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-71283-9

This retrospective study investigates perivascular adipose tissue (PVAT) alterations in CT as a marker of inflammation in patients with abdominal aortic aneurysms (AAA). 100 abdominal CT scans of patients with abdominal aortic aneurysms and 100 age and sex matched controls without underlying aortic disease were included. Artificial Intelligence (AI) assisted segmentation of the aorta and the surrounding adipose tissue was performed. Adipose tissue density was measured in Hounsfield units (HU) close (2-5mm, HU close ) and distant (10-12mm, HU distant ) to the aortic wall. To investigate alterations in adipose tissue density close to the aorta (HU close ) as a potential marker of inflammation, we calculated the difference HU Δ  = HU close -HU distant and the fat attenuation ratio HU ratio  = HU close /HU distant as normalized attenuation measures. These two markers were compared i) inter-individually between AAA patients and controls and ii) intra-individually between the aneurysmal and non-aneurysmal segments in AAA patients. Since most AAAs are generally observed infrarenal, the aneurysmal section of the AAA patients was compared with the infrarenal section of the aorta of the control patients. In inter-individual comparisons, higher HU Δ and a lower HU ratio were observed (aneurysmal: 8.9 ± 5.1 HU vs. control: 6.9 ± 4.8 HU, p-value = 0.006; aneurysmal: 89.8 ± 5.7% vs. control: 92.1 ± 5.5% p-value = 0.004). In intra-individual comparisons, higher HU Δ and lower HU ratio were observed (aneurysmal: 8.9 ± 5.1 HU vs. non-aneurysmal: 5.5 ± 4.1 HU, p-value