Achilles tendon (TA) size and power Doppler ultrasound (PD) changes compared to MRL: A preliminary observational study

AIM: To assess whether abnormal Achilles tendon (TA) magnetic resonance ima ging (MRI) and spectral ultrasound (US) features have associated developmen t of microvascular power Doppler (PD) flow. MATERIALS AND METHODS: In a prospective, controlled and blinded study six p atients with TA symptoms were compared to five with other ankle abnormaliti es. Two radiologists independently measured the mean maximal anteroposterio r diameter on MRI and conventional US (categorized as normal <6 mm, mild 6. 1-10 mm, moderate 1.1-1.5 cm and severely enlarged > 1.6 cm), assessed morp hology and studied the vessels using power Doppler. They formed a consensus over discrepancies. Sonography of the contralateral side within 24 h was u sed as a control. RESULTS: Twenty-one tendons in six women and five men, aged 45-77 years (me an 57.6 years), were examined, 12 tendons were of normal US morphology and size (< 6 mm), and did not exhibit PD's flow (interobserver agreement K > 0 .74). Of the 12 tendons studied by MRI five were normal, seven tendons were enlarged, five of which had a proportionate increase in PD flow at the mar gin on the deep surface and four also had vessels in the centre of the tend on. All five of these tendons had high signal on T2-weighting (T2W). Of the two mildly enlarged tendons of intermediate signal on T1 and T2W, one show ed PD flow and the other did not. CONCLUSIONS: In patients with TA disease power Doppler ultrasound shows pro liferation of vessels in enlarged, abnormal tendons demonstrated on MRI and standard ultrasound, in the absence of definite tears. (C) 2001 The Royal College of Radiologists.