Effect of Nitroglycerin-Enhanced Dual-Energy CT on Imaging Periarticular Arteries in Knee Osteoarthritis: A Prospective Observational Study

RATIONALE AND OBJECTIVES: Accurate visualization of periarticular arteries is crucial for vascular evaluation in knee osteoarthritis (KOA), which often entails complex vascular changes. This study aims to assess the impact of dual-energy computed tomography (DECT) combined with sublingual nitroglycerin (NTG) on the imaging quality of computed tomographic angiography (CTA) in KOA patients. MATERIALS AND METHODS: A prospective observational study was conducted, from January 2024 to October 2024, involving 60 patients with KOA. Participants were divided into two groups: one receiving NTG (n = 30) and a control without NTG (n = 30). Lower-limb CTA was performed using DECT, and 40-keV virtual monochromatic images (VMI) were reconstructed. Evaluation metrics included contrast-to-noise ratio (CNR), arterial diameters, overall image quality, and the number of visible periarticular arteries. RESULTS: NTG administration significantly increased arterial diameters, with the popliteal artery measuring 5.06 ± 0.92 mm vs 5.98 ± 0.84 mm (P < .001) and the middle genicular artery from 0.79 ± 0.27 mm to 1.06 ± 0.30 mm (P < .001). The visualization rate of smaller arteries improved, notably the medial inferior genicular artery from 51.6% to 78.3% (P < .001). Overall image quality scores and CNR were higher in the NTG group (4.77 ± 0.54 vs 3.83 ± 0.73, P < .001; 77.87 ± 21.89 vs 50.25 ± 15.27, P = .002). CONCLUSION: Combining sublingual NTG with 40-keV virtual monochromatic DECT enhances arterial visualization and imaging quality, especially for smaller vessels, indicating potential benefits for preoperative vascular evaluation in KOA management.