Evaluation of superficial neck and deep posteriorneck muscles at obstructive sleep apnea syndromepatients with elastography

The aim of our study was to evaluate muscle strain in neck muscles in patients with OSAS (obstructive sleep apnea syndrome). Patients who presented to Afyon Kocatepe University Faculty of Medicine Department of Chest Diseases Center for Sleep Disorders between May 2012 and July 2012 with moderate-to-severe OSAS diagnosed with single night polysomnography, were included. A total of 50 (26 males, 24 females) healthy control subjects were also included, matched with the study subjects for age and sex with ages between 27-74. Control group was picked out of persons without snoring. Volunteers with previous neck surgery and radiotherapy were excluded. All subjects were assessed with an ultrasonography device with a real-time elastography software. For posterior cervical regional evaluation, C4 level was marked by a skin pen. Next, longitudinal images were obtained by sliding the probe to the right of the neck and rotated 90 degrees. In this study, multifidus muscle and rotatory muscles could not be clearly distinguished and both were named multifidus muscle. Muscles in the posterior cervical region (trapezius, splenius, semispinalis capitis (Sscap), semispinalis cervicis (Sscerv), and multifidus) were insonated via the probe in a way to align them perpendicular to the probe. Assessment of the anterior cervical region was accomplished by imaging sternocleidomastoid (SCM) and strap muscles (sternothyroid and sternohyoid) transversely at the level of thyroid gland after placement of the probe to the anterior aspect of the neck, immediately right to the midline. Mann– Whitney U-tests were employed and a P value of less than 0.05 was considered significant. There was no significant difference between patient and control groups in terms of strain index values for neck muscles (p>0.05). For both patient and control groups, the highest and lowest strain indexes were of semispinalis capitis 44