Quantification of dynamic velopharyngeal port excursion following sphincter pharyngoplasty.

The sphincter pharyngoplasty is a surgical procedure designed to correct velopharyngeal dysfunction. Its advocates cite the theoretical advantage of its induction of dynamic activity of the neovelopharyngeal port, but this dynamic activity has yet to be quantitatively demonstrated in the literature. The purpose of this study was to quantify postoperative velopharyngeal dynamism and to document the results of intervention outcome on sphincteric excursion measurements from minimal-to-maximal orifice closure. We conducted a 7-year retrospective review of speech videofluoroscopy evaluations in patients who had undergone sphincter pharyngoplasty in our center. Between 1989 and 1994, there were 58 patients so treated for postpalatoplasty velopharyngeal dysfunction by two surgeons using the same operative technique. Patients for whom sphincter pharyngoplasty was recommended fulfilled both of the following criteria: (1) velopharyngeal dysfunction caused by an anatomic, myoneural, or combined deficiency of the velopharyngeal sphincter that would not be expected to be managed by speech therapy alone, and (2) preoperative videonasendoscopy and speech videofluoroscopic studies that demonstrated large-gap coronal, circular, or bow-tie closure patterns or velopharyngeal hypodynamism. Of the original 58 patients, 24 underwent postoperative speech videofluoroscopic evaluations with basal views. Of these, 20 of the evaluations (83 percent) were of adequate quality to be included in a research study. Still images showing maximum and minimum excursion of the sphincter in basal view were obtained. To test for observer reliability, the speech videofluoroscopic studies were randomized and presented for measurement to the same individual on two occasions, each session separated by a 1-month time interval. Topographic imaging software was used to obtain maximum and minimum measurements to within 0.1 mm. Partitioning the variance of the data showed that measurement variability was a very small portion of the total, and that difference between the minimum and maximum values was the largest source of variability. Of the total variability in the data, 64.0 percent originated in the minimum/maximum difference, 34.3 percent came from patient variability, and only 1.7 percent resulted from original or repeat measurements. The patient variability may be exaggerated because of variability in the scale of measurement. Results of this study indicate a quantifiable and statistically significant difference in maximum-to-minimum excursion of sphincteric closure. Sphincter pharyngoplasty appears to be dynamic in the majority of cases.

The role of the cranial base in facial growth: experimental craniofacial synostosis in the rabbit.

Craniofacial synostosis designates premature fusion in sutures of the cranial vault (calvarium). When craniofacial synostosis is associated with a syndrome (e.g., Apert, Crouzon), premature fusion of the cranial base has been postulated to occur as well. This study was designed to determine whether the primary growth disturbance in craniofacial synostosis is located at the cranial base (i.e., spheno-occipital synchondrosis) or the calvarial vault (i.e., coronal and sagittal sutures) or both. Sixty newborn New Zealand White rabbits were randomly assigned to six groups: (I) calvarial control, (II) cranial base control, (III) cranial base immobilization, (IV) coronal suture immobilization, (V) coronal and sagittal suture immobilization, and (VI) cranial base and coronal and sagittal suture immobilization. An anterior cervical microsurgical approach to the cranial base was used, while cranial vault sutures were exposed through a bicoronal scalp incision. All sutures were fused by periosteal abrasion and application of methyl cyanoacrylate. Cephalograms were taken at 30, 60, and 90 days postoperatively to assess craniofacial growth. Linear and angular measurements of facial, calvarial, and basicranial growth were subjected to multivariate analysis. Analysis indicated that (1) craniofacial length was shortened most significantly by cranial base fusion, (2) cranial base fusion and cranial vault fusion had an additive effect on craniofacial length restriction, (3) the anterior cranial base was significantly shortened by cranial base and cranial vault fusion (p < 0.05), (4) the posterior cranial base was shortened by cranial base fusion only (p < 0.05), and (5) cranial base fusion alone significantly flattened the cranial base angle (p < 0.05), whereas cranial vault fusion alone did not. These results suggest that cranial base fusion alone may account for many dysmorphic features seen in craniofacial synostosis. This model is consistent with the findings of other investigators and confirms both a primary directive and translational role of the cranial base in craniofacial growth.

Congenital nasal pyriform aperture stenosis. Isolated abnormality vs developmental field defect.

Congenital nasal pyriform aperture stenosis has recently been described as a cause of nasal airway obstruction in the newborn. As some investigators have observed, the nasal pyriform aperture is narrowed owing to bony overgrowth of the nasal process of the maxilla. This overgrowth is confirmed by computed tomography. In six previously reported cases, follow-up as long as 16 months revealed normal facial growth. We describe six patients with congenital nasal pyriform aperture stenosis. On eruption of deciduous dentition, four of the six patients were found to have a single prominent central maxillary incisor, ie, "megaincisor." Computed tomographic scans have confirmed this dental anomaly as well as maxillary bony overgrowth. A single maxillary incisor has been described as an autosomal dominant microform of holoprosencephaly, a developmental field defect. We propose that in some patients congenital nasal pyriform aperture stenosis may represent more than an isolated congenital abnormality of the airway and may, in fact, be a midfacial dysostosis with associated endocrine and central nervous system abnormalities.