ObjectiveTo describe the treatment of adult velopharyngeal insufficiency (VPI) with injection of a hyaluronic acid and dextranomer copolymer (Dx/HA).Patients and MethodsThis was a retrospective case series of 25 consecutively treated adults with VPI who underwent Dx/HA injection pharyngoplasty in a multidisciplinary clinic from January 1, 2011, to December 31, 2014. Data recorded included etiology of VPI, perceptual analysis of resonance, nasalance scores, and estimation of velopharyngeal gap characteristics on video nasendoscopy before and after the intervention. Statistical comparisons were made using a 2-tailed Wilcoxon signed rank test and the Kruskal-Wallis test.ResultsPatients had VPI due to a neurologic etiology, due to a benign anatomic etiology, or acquired after treatment for a head and neck malignancy. Injections were performed with local anesthesia, monitored anesthesia care, or general anesthesia. There were statistically significant improvements in speech resonance, nasalance, and velopharyngeal gap size after treatment. Patients with neurologic or benign anatomic etiologies of their VPI had more significant improvement than those with VPI after treatment of malignancy. Nineteen of the 25 patients required only 1 injection to achieve their final result.ConclusionInjection pharyngoplasty with a readily available Dx/HA is an effective treatment for VPI that allows for titration to complete velopharyngeal closure under local anesthesia or light sedation. It is most effective in patients with nonmalignant etiologies of VPI and in those with good lateral wall motion. Complications experienced were postoperative neck pain and occult retropharyngeal fluid collection, highlighting the importance of follow-up.