Utilization of 3D MRI for the Evaluation of Sphincter Pharyngoplasty Insertion Site in Patients With Velopharyngeal Dysfunction

Abstract

Sphincter pharyngoplasty is a surgical method to treat velopharyngeal dysfunction. However, surgical failure is often noted and postoperative assessment frequently reveals low-set pharyngoplasties. Past studies have not quantified pharyngoplasty tissue changes that occur postoperatively and gaps remain related to the patient-specific variables that influence postoperative change. The purpose of this study was to utilize advanced three-dimensional imaging and volumetric magnetic resonance imaging (MRI) data to visualize and quantify pharyngoplasty insertion site and postsurgical tissue changes over time. A prospective, repeated measures design was used for the assessment of craniometric and velopharyngeal variables postsurgically. Imaging was completed across two postoperative time points. Tissue migration, pharyngoplasty dimensions, and predictors of change were analyzed across imaging time points. Significant differences were present between the initial location of pharyngoplasty tissue and the pharyngoplasty location 2 to 4 months postoperatively. The average postoperative inferior movement of pharyngoplasty tissue was 6.82 mm, although notable variability was present across participants. The pharyngoplasty volume decreased by 30%, on average. Inferior migration of the pharyngoplasty tissue was present in all patients. Gravity, scar contracture, and patient-specific variables likely interact, impacting final postoperative pharyngoplasty location. The use of advanced imaging modalities, such as 3D MRI, allows for the quantification and visualization of tissue change. There is a need for continued identification of patient-specific factors that may impact the amount of inferior tissue migration and scar contracture postoperatively.

Simulation of Velopharyngeal Biomechanics Identifies Differences in Sphincter Pharyngoplasty Outcomes: A Matched Case–Control Study

“…Both participants demonstrated notable inflammation and tissue edema based on MRI data acquired within one week postoperatively. 17 Initial placement of the pharyngoplasty was observed at or above the anterior tubercle of C1 for both participants, consistent with Mason et al 17 Three months postoperatively, the inflammation had resolved, but there was inferior migration of the pharyngoplasty. The SO demonstrated 7.8 mm of inferior migration 3 months postoperatively.…”

“…13 Even with preoperative assessment and intraoperative technique, approximately 13% to 23% of patients are estimated to require additional pharyngoplasty revision at the average time point of 10.4 months after the initial surgery. [14][15][16] Mason et al 17 found that pharyngoplasty tissue migrates inferiorly postoperatively. Tissue edema, external gravitational force, scar contracture, and patient-specific variables were hypothesized to impact the final pharyngoplasty location.…”

“…Tissue edema, external gravitational force, scar contracture, and patient-specific variables were hypothesized to impact the final pharyngoplasty location. [17][18][19][20][21] It remains unknown if variability in the VP anatomy and biomechanical function of the levator muscle further influences surgical outcomes. Understanding how pharyngoplasty placement and VP function might influence the pharyngoplasty outcome may reduce the failure rate and need for additional revision surgery.…”

Magnetic Resonance Imaging for Assessing Velopharyngeal Function: Current Applications, Barriers, and Potential for Future Clinical Translation in the United States

“…These findings suggest that currently published data pertaining to normative measures, indications for use, methodology, and interpretations of results have not yet translated to clinical practice. 10,11,14,[16][17][18]21,[38][39][40][41][42][43] A continued focus on practicebased research is likely to help facilitate the translation of these methods and research findings to clinical practice. 44 Further, many clinicians identified "sedation" or "anesthesia" as a barrier to using MRI for velopharyngeal assessments, indicating a potential procedural barrier.…”

“…As a result, many clinical implications for use of MRI with cleft and craniofacial diagnostics have been proposed. 10,[13][14][15][16][17][18][19][20][21][22][23][24][25] However, the use of MRI in the assessment process for children with cleft and craniofacial conditions remains uncommon in clinical practice on cleft and craniofacial teams, both in its general use by providers on craniofacial teams and particularly for velopharyngeal assessments. Specifically, there has been little systematic discussion of the barriers many clinicians may face when considering the implementation of MRI for clinical practice for this population of patients.…”