Evaluation of the levator veli palatini muscle thickness in patients with velocardiofacial syndrome using magnetic resonance imaging.

Velocardiofacial syndrome (VCFS) is associated with velopharyngeal insufficiency, which occurs in approximately 75% of VCFS patients. Surgical management of velopharyngeal insufficiency in VCFS patients is difficult with a high revision rate due to the anatomic and physiological abnormalities of the velopharynx. The aims of this study were to evaluate the thickness and symmetry of the levator veli palatini (LVP) muscle using magnetic resonance imaging (MRI), and to compare the findings in VCFS patients to those in patients with nonsyndromic submucous cleft palate. We conducted a prospective analysis of 17 VCFS patients (nine boys, eight girls; age range, 4-9 years) and nine patients with submucous cleft palate without VCFS (eight boys, one girl; age range, 4-13 years) who had undergone MRI between March 2009 and August 2013. The thickness of the LVP muscle was measured at six locations in both groups. The symmetry was determined by comparing the values between the average of the left three points and the right three points. The mean LVP muscle thickness was significantly thinner in VCFS patients (2.14 ± 0.73 mm) than in patients without VCFS (3.70 ± 1.08 mm) (p < 0.001). In addition, the difference between the left and right sides of muscle thickness in the VCFS group was larger than that in the nonsyndromic submucous cleft palate group (0.25 and 0.09 mm, respectively). The thinness and asymmetry of the LVP muscle should be considered when determining the surgical management of velopharyngeal insufficiency in VCFS patients.