From the Guidelines
I recommend ordering an MRI of the ankle without contrast to evaluate the Achilles tendon, as it offers high sensitivity in diagnosing ankle tendon tears and can detect partial tears, complete ruptures, tendinosis, and peritendinous edema. The order should specifically request imaging of the ankle with attention to the Achilles tendon, and should include relevant clinical information such as suspected tear, tendinopathy, or other pathology 1. The patient should be positioned supine with the ankle in a neutral position. T1-weighted, T2-weighted, and proton density sequences with fat suppression are typically included in the protocol to provide comprehensive evaluation of tendon integrity, inflammation, and surrounding structures.
Key Considerations
- MRI is the preferred imaging modality for Achilles tendon evaluation because it offers excellent soft tissue contrast and can detect associated pathologies that may not be visible on ultrasound or X-ray 1.
- The examination typically takes 30-45 minutes to complete, and patients should be advised to remove all metal objects before the procedure.
- No special preparation is required, though patients with claustrophobia may benefit from mild sedation arranged in advance.
Imaging Protocol
- The MRI protocol should include:
- T1-weighted sequences to evaluate tendon morphology and detect tendinosis
- T2-weighted sequences with fat suppression to detect inflammation and edema
- Proton density sequences to evaluate tendon integrity and detect partial tears
Clinical Context
- The clinical information provided with the order should include suspected tear, tendinopathy, or other pathology, as well as any relevant medical history or previous imaging studies 1.
- The ordering physician should be aware of the potential for MRI to detect asymptomatic tendon pathology, and should correlate the imaging findings with the patient's clinical symptoms and physical examination results 1.
From the Research
MRI Sequences for Evaluating Achilles Tendon
- The use of fat suppression sequences allows the ability to detect focal lesions 2
- Sagittal and coronal sections are useful for assessing the distance between stumps of a ruptured tendon 2
- Sequences with contrast are indicated in postoperative investigations and suspicion of infection, arthritis or tumor 2
- T1-weighted images following gadolinium contrast medium enhancement proved to be the best method by which to visualize intratendinous signal abnormality 3
Imaging Modalities for Achilles Tendon Pathology
- MRI is superior to ultrasound in detection of partial tears and for postoperative assessment 2
- Ultrasound is the technique of choice for detecting xanthomas 4
- MRI and ultrasound are useful for assessing Achilles tendon pathology, with each modality having its own advantages and technical considerations 5