The reliability of duplex ultrasound in diagnosing popliteal artery entrapment syndrome: An observational pilot study

Abstract

Background and objective: Popliteal artery entrapment syndrome (PAES) is a vascular compression affecting young people. PAES can cause claudication and lead to distal blood flow reduction. Ultrasound could provide a direct and indirect diagnosis approach using different provocative maneuvers. However, the reliability and accuracy of Duplex ultrasound alone to diagnose PAES are uncertain. This study hypothesizes that Duplex ultrasound could lead to false-positive results. Therefore, the study aims to assess the popliteal artery diameter and velocity profile in asymptomatic young people at different provocative maneuvers. Methods: A prospective study of twenty-three limbs of asymptomatic young individuals aged between 21 and 24 was conducted. All individuals were offered a Duplex ultrasound scan of the popliteal and distal runoff arteries at the vascular ultrasound laboratory. Peak systolic velocity (PSV), spectral waveform, the diameter of the popliteal artery, and distal runoff flow velocities were measured at three positions (neutral, active plantarflexion, and erect on top of toes above and below the knee level. These diagnostic parameters were recorded and analyzed. Results: The data was collected over two months; the examined individuals were men with an average age of 23 years and a body mass index of 23.16 kg/m. Popliteal artery diameter above the knee at the neutral position was 5.57 mm, active plantarflexion 5.48 mm, and erect on the top of toes 5.69 mm, (p = 0.624). PSV means above-knee at neutral, active plantarflexion, and erect on the top of toes positions were 50.80, 56.17, and 61.61, respectively, with a p-value of 0.225. There was a significant difference in the diameter and velocity of the popliteal artery below the knee at active plantarflexion and erect on top of toes positions; the mean diameter at neutral was 4.61, at active plantarflexion 4.57, and at erect on top of toes 3.47 (p = 0.018). Furthermore, there was a significant difference in the PSV between measurements, mean at neutral, active plantarflexion, and erect on top of toes, (56.67, 69.43, 93.04) respectively, with a p-value of 0.006. Conclusion: Duplex ultrasound diagnosis is a valuable imaging technique and can provide important information about the diameter and velocity profile of the popliteal artery at different provocative maneuvers. However, our findings suggest that Duplex ultrasound alone would lead to false-positive results and cannot be elusive in determining the asymptomatic from symptomatic patients with PAES.

Keywords

• Popliteal artery
• Entrapment syndrome
• Ultrasound
• Diameter
• Velocity
• Doppler spectral