Elastography: A new diagnostic tool for evaluation of obstructive diseases of the salivary glands; primary results

Purpose: Obstructive diseases of the salivary glands, a common problem in the ENT field, are often based on sialolithiasis but can also result from rare circumstances. Due to recent technical innovations, there has been significant development in the treatment of obstructive diseases of the salivary glands such that minimally invasive glandula-sustaining therapy has now become standard. However, there is still no effective technique to assess and monitor the recovery of the parenchyma of the gland. As a result, recurrent infections often lead to modification of the gland in which fibrosis increases and the gland becomes coarse. After treatment, the parenchyma of the gland is able to recover. Thus, to more effectively monitor and promote the success of treatment, we have developed a new method to measure and quantify the stiffness of the glandula tissue using elastography (Virtual Touch TM Application) to assess the degree of recovery. Materials and methods: First, we collected elastography data from 30 healthy volunteers as part of a conventional ultrasound (Siemens, ACUSON, S 2000, Germany) with a multi-frequency linear 9 MHz transducer in order to determine if normal findings are sufficiently quantifiable. We subsequently measured patients with sialolithiasis of the submandibular gland. Results: For healthy volunteers, the average value was 1.96 ± 0.48 m/s for the glandula submandibularis and 2.66+/- 0.89 for the parotid gland, a statistically significant difference. For patients with sialolithiasis of the submandibular gland, the average value was 2.98 ± 0.4 m/s, a highly significant difference in comparison to the healthy side of the patient. Conclusion: Elastography is an easy to use diagnostic method that shows promise to become a valuable tool for the assessment of disease severity as it provides the possibility to quantify the level of treatment benefit for the patient.