Background: Three-dimensional ultrasound (3D-US) and computed tomography (CT) have proven abdominal aortic aneurysm (AAA) volume a more sensitive measure of growth than diameter. This proof-of-concept study aimed to investigate the clinical applicability of two-dimensional ultrasound and 3D-US for AAA diameter and volume growth pattern evaluation.
Methods: AAA patients with at least three follow-ups within a minimum of 24 months were included prospectively and consecutively from the COpenhagen Aneurysms CoHort (COACH). Individual diameter and volume growth rates were categorized as rapid, slow, or no growth (>6.0, 3.8-6.0, and ≤3.7 mm/year for diameter. >17.4, 8.8-17.3, and ≤8.7 mL/year for volume). Similarly, diameter and volume growth patterns were categorized as as linear, exponential, staccato, and indeterminate growth, based from individual regressions.
Results: Thirty patients were included, of which 19 (63%) had no diameter growth, 10 (33%) had slow growth, and one (3%) had rapid growth. Regarding volume, 11 (37%) patients had no growth, 12 (40%) had slow growth, and seven (23%) had rapid growth. Growth patterns according to diameter showed that 18 (60%) patients had linear growth, none had staccato or exponential growth. Twelve (40%) were indeterminate. Volume growth patterns found 19 (63%) patients with linear growth, 3 (10%) with staccato, and none with exponential growth. Eight (27%) were indeterminate.
Conclusions: Analysis of AAA volume growth patterns is a practical and safe modality that seems more sensitive at detecting growth patterns than AAA diameter. Volume also detects more AAA growth than diameter.