On the variability of velopharyngeal valve anatomy and function: a combined peroral and nasendoscopic study.

The oropharynx stripped of the tonsils and the excessive mucosal folds after the uvulopalatopharyngoplasty operation allows a closed observation of the outline of the pharyngeal muscles. Forty-two consecutive patients undergoing uvolopalatopharyngoplasty were subjected to peroral examination of the oropharynx combined with nasendoscopic examination of the velopharyngeal valve. At rest, the oropharynx of the patients with coronal closure patterns was found to be flat relative to the oropharynx of the patients with the other closure patterns. During closure of the velopharyngeal valve, an anteroposterior movement of the velum, forming the nasendoscopic coronal closure pattern, was observed in patients with a flat oropharynx. On the other hand, a medial movement of the pharyngeal walls was found, forming the circular or sagittal closure pattern seen in patients with a deep oropharynx. Our conclusion is therefore that a different muscular orientation is responsible for both the different pharyngeal configuration at rest and the different contribution of the lateral and posterior pharyngeal walls to velopharyngeal valve closure.     

Does velopharyngeal closure pattern affect the success of pharyngeal flap pharyngoplasty?

Historically at The Hospital for Sick Children in Toronto, pharyngeal flap pharyngoplasty has been the treatment of choice for treatment of velopharyngeal insufficiency, regardless of velopharyngeal closure pattern. The authors hypothesize that pharyngeal flap pharyngoplasty is more effective in treating velopharyngeal insufficiency in patients with circular or sagittal velopharyngeal closure and less effective in treating the coronal closure pattern. Ninety-three patients who underwent superiorly based pharyngeal flap surgery for velopharyngeal insufficiency were evaluated in a retrospective chart review. Closure pattern was determined preoperatively by nasopharyngoscopy or multiview videofluoroscopy. Nasalance was assessed preoperatively and at 6 weeks and 1 year postoperatively. Nasalance during nonnasal speech was decreased on average, for all closure patterns, postoperatively. However, a significantly higher percentage of patients were corrected to normal nasalance scores in thenoncoronal group than in the coronal group (57 percent versus 35 percent, respectively) at 1 year postoperatively (p < 0.05). Surgical overcorrection, as determined by postoperative hyponasality, occurred at a rate of 13 percent in the coronal group versus 7 percent in the noncoronal group (not statistically significant). The results demonstrate that hypernasality in patients with a coronal velopharyngeal closure pattern can be improved by pharyngeal flap pharyngoplasty. This procedure, however, is more frequently effective in correcting noncoronal closure pattern velopharyngeal insufficiency than coronal pattern velopharyngeal insufficiency. The authors are now more selective in their approach to the management of velopharyngeal insufficiency and are more inclined to treat coronal pattern velopharyngeal insufficiency with sphincter pharyngoplasty.     

Positive narrowing pharyngoplasty with forearm flap for functional restoration after extensive soft palate resection

The restoration of velopharyngeal function after extensive soft palate resection to treat malignant oropharyngeal tumors is a major challenge to reconstructive surgeons. The authors had previously reconstructed soft palatal defects routinely with the folded forearm flap. A patient who had more than half of the soft palate excised experienced postoperative velopharyngeal dysfunction. To restore efficient velopharyngeal function, pharyngoplasty was additively applied where the folded ridge of the forearm flap was sutured to the posterior pharyngeal wall in an inverse manner of the pharyngeal flap technique. The essence of the procedure was positive narrowing of the nasopharyngeal space. Five patients who underwent this pharyngoplasty and another five who did not were evaluated for postoperative functions of speech intelligibility and of nasal regurgitation during oral feeding. The velopharyngeal movements of all patients were examined under a nasopharyngeal endoscope. The evaluations demonstrated that this surgical procedure afforded satisfactory results. This positive narrowing pharyngoplasty technique is simple, easy, and minimally invasive to the remaining healthy tissue, and it is the method of choice for the reconstruction of the soft palate after malignant tumor resection.     

Speech results of the Zürich approach in the treatment of unilateral cleft lip and palate

The purpose of this study was to describe perceptually the speech articulation, voice quality, and velopharyngeal competency of subjects with complete unilateral cleft lip and palate treated by the Zürich approach. The mean age of the 37 subjects was 10.5 years. Although only one subject had had secondary palatal management, no subject was rated as exhibiting a severe articulation or nasality problem. Subjects were rated as exhibiting adequate to marginal velopharyngeal competency 94.5 percent of the time, and the incidence of compensatory articulation errors was low. In comparison with other studies that evaluated the two-stage palatal repair, the Zürich approach appears to give the better results. The type of initial soft palate repair is probably the significant factor which contributes to the better speech of these subjects.     

An outcome evaluation of sphincter pharyngoplasty for the management of velopharyngeal insufficiency

Sphincter pharyngoplasty is frequently used for the management of children with velopharyngeal insufficiency. The purpose of this study was to evaluate outcome and revision rates of sphincter pharyngoplasty at the authors' institution. Two hundred fifty patients underwent sphincter pharyngoplasty for velopharyngeal insufficiency between January of 1987 and March of 2001. There were 117 female patients and 133 male patients, with a mean age at primary sphincter pharyngoplasty of 7.6 years (range, 1 to 45 years). Diagnoses included velopharyngeal insufficiency alone (n = 63), velopharyngeal insufficiency associated with cleft palate (n = 127), velocardiofacial syndrome (n = 32), submucous cleft (n = 15), and other (n = 13). Pharyngoplasty revision was defined as any secondary surgical revision of the sphincter as determined by clinical evaluation and objective speech assessment. The pharyngoplasty revision rate was found to be 12.8 percent (n = 32). A favorable outcome was demonstrated in 30 of these patients (93.8 percent) after pharyngoplasty revision. Two patients, one with a diagnosis of a submucous cleft and velocardiofacial syndrome and the other with a cleft palate, required a second revision because of persistent velopharyngeal insufficiency. The revision rate was highest in those patients with velocardiofacial syndrome (21.8 percent) and lowest in patients with velopharyngeal insufficiency alone (6.3 percent). Patients who required revision had significantly higher preoperative oral sentence nasometry (55.2 percent versus 46.1 percent; p < 0.01) and larger velopharyngeal areas (23.7 mm2 versus 18.9 mm2). There was no significant difference in age or sex for those patients who required a revision compared with those who did not require revision. Mean follow-up was 2.4 years (range, 4 months to 13.6 years). Sphincter pharyngoplasty is an effective procedure for the treatment of velopharyngeal insufficiency using revision rate as the standard of success. It had an 87 percent primary success rate that increased to 99 percent after a single revision. Patients with velocardiofacial syndrome, more severe preoperative hypernasal resonance, and larger velopharyngeal areas were more likely to require pharyngoplasty revision.     

Levator veli palatini muscle and eustachian tube function

Thirty previously unoperated patients with submucous cleft palate, occult submucous cleft palate, and unilateral congenital paralysis of the levator veli palatini muscle were examined. All patients were subjected to a comprehensive otoscopic, endoscopic, audiologic, and tympanometric evaluation. A correlation was made between levator veli palatini muscle anomalies, eustachian tube orifice anomalies, and middle ear ventilation and disorders. Normal middle ear ventilation was found in 23 patients. Negative middle ear pressure that consequently normalized following treatment of coexisting sinusitis was found in 3 patients. Only in 4 patients was chronic middle ear disease found. In one of them, middle ear effusion disappeared following successful treatment of sinusitis. Our conclusion is that the levator veli palatini muscle has no significant function in the opening mechanism of the eustachian tube and must be considered as a velopharyngeal valve muscle only.     

The dermatoglyphic and clinical features of the 9p trisomy and partial 9p monosomy syndromes

Summary The physical and dermatoglyphic features obtained from published reports of 128 patients with the trisomy 9p syndrome and 27 patients with the partial 9p monosomy syndrome are tabulated. This information is also provided on two new individuals with each of these chromosomal disorders. The dermal ridge patterns and palmar creases of trisomy 9p which are most helpful from a diagnostic standpoint are zygodactylous or absent palmar digital triradii, brachymesophalangy, reduced total finger ridge count, complex thenar/ID I patterns, transverse palmar ridge alignment, simian creases, distal axial triradii, and great toe and hallucal arch patterns. The characteristic features in partial 9p monosomy include dolichomesophalangy with accessory finger flexion creases, digital whorl patterns and elevated total finger ridge count, distal axial triradii, simian creases, and palmar dermal ridge dissociation.     

Velopharyngeal function following maxillary advancement.

In a series of 40 patients who had maxillary advancements, none developed velopharyngeal incompetence. Unlike the cleft palate patient who is more at risk, there are distinct anatomical characteristics in craniofacial dysostosis which favor maintenance of the integrity of the velopharyngeal mechanism. Hyponasality was eliminated in 5 patients with Crouzon's disease. On cephalometric study, it was observed that after maxillary advancement the nasopharyngeal volume was expanded and the angle formed by the hard and soft palates was increased. On phonating cephalograms, the velopharyngeal contact became more physiological after maxillary advancement in the craniofacial dysostosis patient. The only postoperative articulatory changes after maxillary advancement were in the production of the /s/ sound, which is particularly sensitive to changes in dentoalveolar relationships.     

Velopharyngeal surgery: a prospective randomized study of pharyngeal flaps and sphincter pharyngoplasties

Residual velopharyngeal insufficiency after palatal repair varies from 10 to 20 percent in most centers. Secondary velopharyngeal surgery to correct residual velopharyngeal insufficiency in patients with cleft palate is a topic frequently discussed in the medical literature. Several authors have reported that varying the operative approach according to the findings of videonasopharyngoscopy and multiview videofluoroscopy significantly improved the success of velopharyngeal surgery. This article compares two surgical techniques for correcting residual velopharyngeal insufficiency, namely pharyngeal flap and sphincter pharyngoplasty. Both techniques were carefully planned according to the findings of videonasopharyngoscopy and multiview videofluoroscopy. Fifty patients with cleft palate and residual velopharyngeal insufficiency were randomly divided into two groups: 25 in group 1 and 25 in group 2. Patients in group 1 were operated on by using a customized pharyngeal flap according to the findings of videonasopharyngoscopy and multiview videofluoroscopy in each case. Those in group 2 received a sphincter pharyngoplasty also customized according to the findings of videonasopharyngoscopy and multiview videofluoroscopy. The median age of the patients in both groups was not significantly different (p > 0.5). The frequency of residual velopharyngeal insufficiency after the individualized velopharyngeal surgery was not significantly different between the patient groups (12 percent versus 16 percent; p > 0.05). It seems that customized pharyngeal flaps and sphincter pharyngoplasties performed according to the findings of videonasopharyngoscopy and multiview videofluoroscopy are safe and reliable procedures for treating residual velopharyngeal insufficiency in cleft palate patients.     

Surgical treatment of submucous cleft palate: a comparative trial of two modalities for palatal closure

Submucous cleft palate is a congenital malformation with specific clinical and anatomical features. It can be present with or without velopharyngeal insufficiency. Surgical treatment of this malformation is indicated only when velopharyngeal insufficiency has been demonstrated. This article compares two modalities of surgical treatment for submucous cleft palate. The first includes a minimal incision palatopharyngoplasty, as described in a previous report. The second combines the first technique with additional individualized velopharyngeal surgery (individualized pharyngeal flap or sphincter pharyngoplasty) performed simultaneously. The individualized part of the procedure was selected and performed according to the findings of videonasopharyngoscopy and multiview videofluoroscopy, as reported previously. Two hundred and three patients with submucous cleft palate were studied from 1990 to 1999. Videonasopharyngoscopy and multiview videofluoroscopy demonstrated velopharyngeal insufficiency in 72 patients, who were randomly divided into two groups. Those in group 1 (n = 37) underwent a minimal incision palatopharyngoplasty. Patients in group 2 (n = 35) also underwent that procedure but simultaneously received individualized pharyngeal flap or sphincter pharyngoplasty, according to the findings of videonasopharyngoscopy and multiview videofluoroscopy. The median age of the patients from both groups was not significantly different (p > 0.5). The frequency of residual velopharyngeal insufficiency after palatal closure was not significantly different in both groups of patients (14 percent versus 11 percent; p > 0.5). The mean size of the gap at the velopharyngeal sphincter during speech was not significantly different in both groups of patients before surgery (23 percent versus 22 percent; p > 0.5). After the surgical procedures, there was a nonsignificant difference between both groups of patients in mean residual size of the gap in cases of velopharyngeal insufficiency (7 percent versus 8 percent; p > 0.5). It seems that minimal incision palatopharyngoplasty is a safe and reliable procedure for palatal closure in patients with submucous cleft palate. The use of additional individualized velopharyngeal surgery performed simultaneously did not seem to decrease the frequency of residual velopharyngeal insufficiency. Moreover, the residual size of the gap at the velopharyngeal sphincter was not significantly reduced when an additional surgical procedure was performed simultaneously with palatal closure.     

Velopharyngeal motion after sphincter pharyngoplasty: a videonasopharyngoscopic and electromyographic study

Sphincter pharyngoplasty is a surgical procedure for managing velopharyngeal insufficiency after palatal closure. This procedure is intended to create an active diaphragm for velopharyngeal closure. The purpose of this study was to evaluate velopharyngeal motion after sphincter pharyngoplasty, by using selective electromyography and simultaneous videonasopharyngoscopy. Twenty-five patients who were subjected to sphincter pharyngoplasty from 1985 to 1996 were reviewed. All conditions were evaluated by using electromyography with simultaneous videonasopharyngoscopy. The following velopharyngeal muscles were examined: superior constrictor pharyngeus, palatopharyngeus, and levator veli palatini. The palatopharyngeus was included in the superiorly based surgical flaps inserted at the posterior pharyngeal wall. Twenty-three patients (92 percent) showed complete velopharyngeal closure. The two patients with residual velopharyngeal insufficiency showed a defect size of 20 and 25 percent. None of the patients showed electromyographic activity at the superiorly based flaps, indicating absence of activity of the palatopharyngeus muscles. However, all patients showed normal electromyographic activity at the superior constrictor pharyngeus and the levator veli palatini. Videonasopharyngoscopy demonstrated that lateral pharyngeal wall movements, which ranged from 25 to 40 percent, were related to strong electromyographic activity at the superior constrictor pharyngeus. It is concluded that the superiorly based pharyngeal flaps of the sphincter pharyngoplasty do not seem to create an active diaphragm for velopharyngeal closure. Moreover, the observed sphinctering seems to be passive, caused by the contraction of the superior constrictor pharyngeus.     

Influence of palatal fistulas on velopharyngeal movements: a cineradiographic study

Ten patients with hard palate fistulas and velopharyngeal incompetence were examined cineradiographically with lateral and frontal projections during connected speech. The purpose was to study velopharyngeal function for open versus covered fistulas. Fistula length, width, and size were measured. With an open fistula, the degree of lateral pharyngeal wall activity was significantly correlated at the 0.05 level to fistula size. There was no statistically significant correlation between fistula size and the degree of velar activity. With the fistula covered, the velopharyngeal movements improved or even normalized in all patients regardless of fistula size. These findings indicate that patients with both velopharyngeal incompetence and an additional fistula will need covering of the fistula. If velopharyngeal incompetence persists after a temporary covering of the fistula, a combination of velopharyngeal flap surgery and fistula covering ought to be performed to normalize the velopharyngeal activity and speech and resonance.     

Radiographic and aerodynamic measures of velopharyngeal anatomy and function following Furlow Z-plasty

Recent studies have shown that the Furlow double-opposing Z-plasty has several advantages that make it an attractive procedure for cleft palate repair and treatment of velopharyngeal insufficiency in selected cases. The anatomic changes associated with this procedure have never been documented prospectively. The purpose of this study was to describe radiographic dimensions of the velopharynx and aerodynamic measures of velopharyngeal function in a group of patients before and after Furlow Z-plasty for the treatment of velopharyngeal insufficiency. Twelve consecutive patients with cleft palate and velopharyngeal insufficiency, ranging in age from 3 to 19 years, were selected as candidates for Furlow Z-plasty based on perceptual, endoscopic, and radiographic findings. Eight patients had repaired cleft palate with a residual muscle diastasis and four patients had unrepaired submucous cleft palate. Subjects received aerodynamic and cephalometric assessments before and after Z-plasty. Cephalometric x-rays were measured for velar length, thickness, and pharyngeal depth. Mean nasal airflow during pressure consonants (Vn) was calculated from pressure/flow studies, and patients were categorized as having complete closure (<10 cc/sec Vn) or incomplete closure (>10 cc/ sec Vn). After Z-plasty, there was a significant increase in velar length (p = 0.002) and velar thickness (p = 0.001). After surgery, patients with complete velopharyngeal closure had significantly greater velar length than the incomplete closure group (p = 0.05) with nearly twice the increase in length. Similarly, following surgery, the complete closure group had significantly greater thickness than the incomplete closure group (p = 0.01), with a greater postoperative increase in velar thickness (p = 0.005). Finally, there was a significant negative correlation between percent increase in length and percent increase in thickness for patients in the complete closure group (r = -0.91, p = 0.03). Findings demonstrate that following Furlow Z-plasty, patients with cleft palate and velopharyngeal insufficiency obtained significant increases in velar length and thickness. Greater velar length and greater velar thickness both were associated with complete velopharyngeal closure. Patients in the complete closure group tended to demonstrate large percent gains in either length or thickness or moderate gains in both. Patients in the incomplete closure group tended to demonstrate relatively small percent gains in both dimensions. Results suggest there may be important anatomic features (such as pharyngeal depth/velar length ratio) that can be evaluated before surgery to predict which patients may be most likely to benefit from Furlow Z-plasty as a form of treatment for velopharyngeal insufficiency.     

The potential for and constraints on the evolution of compensatory ability in Asclepias syriaca

To investigate the potential for and constraints on the evolution of compensatory ability, we performed a greenhouse experiment using Asclepias syriaca in which foliar damage and soil nutrient concentration were manipulated. Under low nutrient conditions, significant genetic variation was detected for allocation patterns and for compensatory ability. Furthermore, resource allocation to storage was positively, genetically correlated both with compensatory ability and biomass when damaged, the last two being positively, genetically correlated with each other. Thus, in the low nutrient environment, compensatory ability via resource allocation to storage provided greater biomass when damaged. A negative genetic correlation between compensatory ability and plant biomass when undamaged suggests that this mechanism entailed an allocation cost, which would constrain the evolution of greater compensatory ability when nutrients are limited. Under high nutrient conditions, neither compensatory ability nor allocation patterns predicted biomass when damaged, even though genetic variation in compensatory ability existed. Instead, plant biomass when undamaged predicted biomass when damaged. The differences in outcomes between the two nutrient treatments highlight the importance of considering the possible range of environmental conditions that a genotype may experience. Furthermore, traits that conferred compensatory ability did not necessarily contribute to biomass when damaged, demonstrating that it is critical to examine both compensatory ability and biomass when damaged to determine whether selection by herbivores can favor the evolution of increased compensation. Received: 2 April 1999 / Accepted: 21 September 1999     

Use of the pharyngeal flap in the treatment of congenital velopharyngeal incompetence

Seventy-four patients were referred to the senior author because of presumed velopharyngeal incompetence without cleft palate. As a result of an extensive preoperative evaluation that included assessment of articulation patterns, nasal emission, oronasal resonance, and general speech intelligibility, 57 of the 74 patients were selected for a pharyngeal flap procedure. In 54 of the 57 patients (95 percent), the operation corrected inappropriate nasal emission and hypernasality and improved intraoral air pressure to allow normal speech production.     

A single surgeon's experience with the Delaire palatoplasty

The purpose of this review was to evaluate the clinical outcomes regarding velopharyngeal insufficiency and fistulization in patients with cleft palate who underwent primary repair with the one-stage Delaire palatoplasty. All patients who had a primary Delaire-type palatoplasty performed by the senior surgeon over a 10-year period (1988 to 1998) were studied. During this period, each consecutive patient with an open palatal cleft underwent the same type of repair by the same surgeon. Speech quality and velopharyngeal competence as determined by a single speech pathologist were recorded. A total of 95 patients were included in this series. The average length of follow-up was 31 months (range, 1 to 118 months). Average age at time of surgery was 13.3 months (range, 6 to 180 months). Thirty-one patients (32.6 percent) had significant associated anomalies. The average length of hospital stay was 1.9 days (range, 1 to 8 days) with a trend in recent years toward discharge on postoperative day 1. There were no intraoperative complications, either surgical or anesthetic. Three patients (3.2 percent) developed palatal fistula; none of them required repair. Six patients (6.3 percent) had velopharyngeal incompetence. In patients with more than 1 year of follow-up, the incidence of velopharyngeal incompetence was 9.2 percent (6 of 65). The incidence of fistula after the Delaire palatoplasty was lower than usually reported. The incidence of velopharyngeal incompetence requiring pharyngoplasty was equal to or lower than that seen after other types of palatoplasty, suggesting superior soft-palate muscle function attributable to approximation of the musculus uvulae. The Delaire palatoplasty results in a functional palate with low risk for fistula formation and velopharyngeal incompetence.     

Results with Furlow palatoplasty in management of velopharyngeal insufficiency.

A retrospective study was undertaken to assess speech outcomes in patients undergoing Furlow palatoplasty. Since 1994, the authors have used the position of the levator veli palatini musculature to determine type of surgical intervention recommended for the management of velopharyngeal insufficiency. Furlow palatoplasty has been used in patients with clinical evidence of sagittally oriented levator veli palatini musculature. Forty-eight patients who underwent a Furlow palatoplasty between June of 1994 and August of 1998 were included. All patients underwent preoperative and postoperative perceptual speech analyses to describe velopharyngeal insufficiency severity, nasal air emissions, and resonance, and preoperative nasendoscopy to assess velopharyngeal gap size and palatal and lateral pharyngeal wall movement. Other patient characteristics considered included gender, age at time of surgery, previously repaired cleft palate, submucous cleft palate, and syndrome diagnosis. Speech outcomes were determined on the basis of postoperative perceptual speech analyses and were categorized in one of three ways: (1) complete resolution of velopharyngeal insufficiency, (2) substantial improvement of velopharyngeal insufficiency, and (3) audible residual velopharyngeal insufficiency. Complete resolution of velopharyngeal insufficiency was defined as normal resonance and an absence of nasal air emissions. Substantial improvement of velopharyngeal insufficiency was defined as an improvement of at least two categories in velopharyngeal insufficiency severity in those patients without complete resolution. Audible residual velopharyngeal insufficiency refers to patients with postoperative velopharyngeal insufficiency severity ratings of mild, moderate, or severe. The male:female ratio in the study was 27:21. Twelve patients were syndromic; three had velocardiofacial syndrome. The median age at surgery was 6.5 years (range, 2 to 22 years). The average duration of follow-up was 14.7 months (range, 1.3 to 58.6 months). Postoperatively, the severity of velopharyngeal insufficiency was rated as none in 19 of the 48 patients (39.6 percent), minimal in eight (16.7 percent), mild in six (12.5 percent), moderate in nine (18.75 percent), and severe in six (12.5 percent). Substantial improvement was seen in seven of the 29 patients without complete resolution. There was a significant association between male gender and complete resolution of velopharyngeal insufficiency (p < 0.05). Presence of syndrome and female gender was associated with audible residual velopharyngeal insufficiency (p < 0.05). The main complication was palatal fistula (two cases). In conclusion, most patients who underwent a Furlow palatoplasty had a complete resolution or substantial improvement of velopharyngeal insufficiency postoperatively, and there were few surgical complications.     

A comparison between the inlet and outlet diameters of the normal aortic valve.

Two studies are described comparing the inlet and outlet diameters of the normal aortic valve. Both studies show the valve inlet to be smaller than the valve outlet. The first study is of measurements made on 12 casts of physiologically pressurised human aortic valves. The mean ratio between the diameter of the aortic ring and of the aorta just distal to the sinus ridge was 1.1, and the mean ratio between the diameter of the aortic ring and the maximum diameter of the valve leaflets was 1.18. The second study presents echocardiographic data from normal volunteers. The mean ratio between the diameter of the aortic ring and of the aorta just distal to the sinus ridge was 1.17. It is suggested that stents made to support the leaflets of prosthetic valves are made in conical or hyperbolic form, with the outlet being approximately 20% larger than the inlet.     

Predictors of velopharyngeal insufficiency in cleft palate orthognathic surgery

The purpose of this study was to appraise the value of preoperative speech assessments, nasopharyngoscopy, and surgical models as predictors of velopharyngeal deterioration after a Le Fort I maxillary advancement in cleft patients. This retrospective study involved a series of 26 cleft patients (16 unilateral complete and nine bilateral complete cleft lips and palates, and one isolated complete cleft palate) who had Le Fort I maxillary advancements between March 1, 1993, and February 7, 1996. The 13 male patients and 13 female patients ranged in age from 15.3 to 46 years (mean age, 19.5 years). Four of these patients had previously undergone pharyngeal flap surgery. Eleven patients had palatal fistulas and one had a bifid uvula that was repaired at the time of orthognathic surgery. Patients with perceived hypernasal speech preoperatively all had hypernasality after advancement (nine of nine). Velopharyngeal insufficiency was observed in two of the 16 whose resonance preoperatively was within normal limits. Speech assessment, therefore, predicted accurately the postoperative status in 23 of 26 patients. Twelve patients had preoperative nasopharyngoscopy that indicated a high risk for velopharyngeal insufficiency (borderline or inadequate closure). Nine of these patients had postoperative velopharyngeal insufficiency. Two of the 14 patients not judged at risk by nasopharyngoscopy developed velopharyngeal insufficiency. Therefore, 21 of the 26 patients were accurately predicted by nasopharyngoscopy. Scoping detected borderline velopharyngeal insufficiency in one patient who was not detected by speech alone. The combined predictive value of speech and scope identified all but one patient who would develop postoperative velopharyngeal insufficiency. The degree of anteroposterior movement determined from surgical models was not predictive of the outcome. Patients with hypernasal speech preoperatively continue to have hypernasal speech after Le Fort I advancement. Preoperative perceptual speech assessment by specially trained speech-language pathologists is an excellent test for predicting postoperative velopharyngeal insufficiency status. Nasopharyngoscopy is an invasive and resource-dependent test that should be assessed with respect to cost effectiveness. In this series, only one patient's risk was more accurately predicted using nasopharyngoscopy than by speech assessment alone.     

Evidence for plasticity of the dopaminergic system in Parkinsonism

A series of compensatory mechanisms within the dopaminergic system have been shown to maintain clinical function in the presence of dopamine loss. Experimental evidence for increased presynaptic dopamine turnover owing to increased dopamine synthesis, release, and reduced reuptake exists. Direct evidence that these mechanisms maintain extracellular dopamine levels is provided by intracerebral microdialysis techniques. Postsynaptic denervation supersensitivity clearly occurs with D2 dopamine receptors, although this is less evident with D1 receptors. Similarly, mechanisms of plasticity have been shown to be relevant in human postmortem and Positron Emission Tomographic studies of patients with Parkinson's disease. However, although presynaptic increases in dopamine turnover are well documented, postsynaptic D1 and D2 receptor changes have been more difficult to establish, mainly because of methodological difficulties. D2, but not D1, receptor increases have been documented in drug naive Parkinsonian patients with PET techniques. In transplantation of adrenal gland to striatum in animal models and patients with Parkinsonism where clinical improvement occurs, plasticity of host response may be as important as plasticity of the graft. Although some elements of the compensatory mechanism of dopamine plasticity may be deleterious, such as dyskinesias owing to dopamine receptor supersensitivity, the overall effect of delay and minimization of the clinical expression of disease is advantageous. An even greater understanding of the mechanisms involved may assist in developing future therapeutic strategies.