Collagen-sensitive dual-energy-CT as a quantitative tool for tendinopathy assessment: a prospective diagnostic...

The purpose of this study was to evaluate the effectiveness of collagen-sensitive dual-energy computed tomography (DECT) as a quantitative imaging tool for the assessment and monitoring of load-induced tendinopathy in the Achilles and patellar tendons, comparing it to magnetic resonance imaging (MRI).

In a prospective study, 15 consecutive patients clinically diagnosed with Achilles or patellar tendinopathy underwent bilateral DECT and MRI at baseline and 6 months. Quantitative measurements included collagen density assessed via DECT and signal intensity via MRI. Clinical symptoms were evaluated using numerical pain ratings and VISA-A/P scores. The diagnostic accuracy of both imaging modalities was assessed using ROC analysis, and correlations between DECT and MRI findings were investigated.

DECT revealed significantly lower collagen densities on corresponding maps in affected tendons (n = 18, 23.7 ± 20.2) compared to unaffected tendons (n = 12, 60.2 ± 29.6 HU, p < 0.001), whereas MRI demonstrated increased signal intensities in pathological regions. ROC analysis indicated comparable diagnostic performance for DECT (AUC = 0.84) and MRI (AUC = 0.80). A strong inverse correlation (r = -0.83) was observed between DECT-measured collagen densities and MRI signal intensities. Clinical improvements at follow-up were reflected by normalization trends in both imaging modalities, though not statistically significant.

Collagen-sensitive DECT provides a reliable quantitative approach for detecting and assessing tendon pathologies in load-induced tendinopathy, demonstrating diagnostic capabilities comparable to MRI while offering the possibility for collagen density quantification.