22q11.2 Deletion Syndrome (22q) is the most common microdeletion known in humans. Studies have hypothesized that larger nasopharyngeal proportions lead to velopharyngeal dysfunction (VPD) in individuals in 22q.22q patients that undergo the pharyngeal flap surgery to correct their velopharyngeal insufficiency have been reported to experience an increased rate of surgical complications due to their complex anatomical differences.Treatment of velopharyngeal insufficiency among patients with 22q therefore requires quantitative anatomical data of the nasopharyngeal area for surgical planning. No studies to date have analyzed the nasopharyngeal volume in a non-sedated pediatric population with 22q. The aim of this study was to investigate the volumetric and linear characteristics of the nasopharyngeal port among children with 22q using a novel, non-sedated 3D imaging protocol.

MRI data were obtained on 20 participants, 10 with a confirmed diagnosis of 22q and 10 control subjects. All participants were between 4-12 years of age. 3D MRI data were collected while the velum was relaxed as the participants lay in the supine position. The 3D scan involved a 0.8 in-plane isotropic resolution with an acquisition time of less than 5 minutes.MRI data were transferred into Amira 6 Visualization Volume Modeling software (Visage Imaging GmbH, Berlin, Germany). Both volumetric and linear measurements of the nasopharyngeal port were taken. The measures were selected based on relevance to speech resonance features and comparable studies in the literature. Linear measurements were taken of the velopharyngeal (VP) width, anterior cranial base angle (ACBA), pharyngeal depth, osseous pharyngeal depth, and adenoid-nasopharyngeal ratio (ANR). Volumetric measurements included adenoid volume (AV), nasopharyngeal volume (NPV), and oronasopharyngeal volume (ONV) . Independent samples t-tests were used to assess differences between the control and clinical groups.

The total volume of the nasopharynx was found to be significantly larger in the 22q group (2890.70 mm3) compared to the control group (1542.10 mm3). Significant differences were additionally noted among linear measures, including a more obtuse angle of the ACBA in the 22q group. These results support our initial hypothesis regarding larger nasopharyngeal airways in patients with 22q compared to the control group. Quantitative anatomical data of nasopharyngeal proportions in children with 22q can be used to tailor surgery to provide a more personalized treatment approach to enhance speech and surgical outcomes in the 22q population.

Thesis Completion




Thesis Chair/Advisor

Kollara Sunil, Lakshmi


Bachelor of Science (B.S.)


College of Health Professions and Sciences


Communication Sciences and Disorders



Access Status

Campus Access

Length of Campus-only Access

5 years

Release Date