David K. Chong

Analysis of morbidity and mortality in surgical management of craniosynostosis.

Abstract Multidisciplinary care involving plastic surgery and neurosurgery is generally accepted as optimal to manage craniosynostosis to avoid complications and to identify patients at risk. We conducted a retrospective 30-year review of craniosynostosis surgery at a single major craniofacial institute to establish the rate and predictors of complications. Medical records of 796 consecutive patients who underwent primary surgery for craniosynostosis from 1981 to 2010 at our institute were analyzed for complications. Complications were defined as intraoperative and postoperative adverse events requiring changed management. Reoperation was defined as a repeat transcranial procedure. Multivariate logistic regression was used to identify predictors for complications or revision. Across the years, the procedures evolved from technically simple to complex, which increased complications but better outcomes. Complications occurred in 111 patients (14%), and 33 (5.4%) needed major revision. Multivariate analysis identified multisuture and syndromic craniosynostosis, more recent surgeries, younger age (<9 months), spring-assisted cranioplasty, longer surgery, and greater transfusion as predictors of complications. Patients with syndromic and multisutural craniosynostosis and those operated on younger than 9 months had increased risk of major revision surgery for regression to phenotype. Our experience over 30 years indicates that pediatric transcranial craniosynostosis surgery can be safely carried out in our tertiary referral center. There were no deaths from primary surgery, and complication and reoperation rates mirror those of other published studies. Syndromic and complex craniosynostosis predicted both complications and need for major revision. Spring cranioplasty was associated with higher complications. Overall results support a recommended age for craniosynostosis surgery between 9 and 12 months.

Measuring cranial vault volume with three-dimensional photography: a method of measurement comparable to the gold standard.

The gold standard for measuring cranial vault volume is a computed tomography (CT) scan. Computed tomography scans in the pediatric population carry the significant risk of inducing a malignancy later in life. In a novel study, we show that a three-dimensional (3D) photograph can be used to measure and track cranial vault volume changes in craniosynostosis patients. In a study of adequate power as determined by pre hoc analysis, we demonstrate a greater than 0.91 correlation coefficient between volume as measured by CT and 3D photograph in more than 70 patients presenting to a tertiary craniofacial center (P < 0.001). Volume above a plane running through the lateral canthus (ex) and tragus (t) sag-ex-t on the digital 3D photograph differs from CT by a mean percentage difference of 31.9% (SD, 14.0%; 95% confidence interval, P < 0.0001). A linear regression model was used to determine the equation describing the relationship between volume as measured by 3D photograph and CT; with this equation, the absolute volume of the cranial vault is easily determined using only the 3D image. Interrater reliability is high (>0.99, ICC). The ability to measure cranial vault volume from the 3D photograph adds an important dimension to the complete and objective analysis of skull growth and postoperative change.

Changing epidemiology of nonsyndromic craniosynostosis and revisiting the risk factors.

Abstract Recent studies in Europe and the United States report increased incidence of metopic synostosis. Whether a similar trend had occurred in Australia remains unknown. This research aimed to determine changes in incidence and subtypes of craniosynostosis in Victoria and to identify perinatal risk factors. A retrospective audit of patients (n = 522) presenting to the Royal Children’s Hospital in Melbourne with nonsyndromic craniosynostosis from 1982 to 2008 was undertaken. Perinatal data were sourced from the Victorian Perinatal Data Collection. The changes in incidence of craniosynostosis subtypes were calculated based on Poisson regression, and risk factors for craniosynostosis and subtypes were analyzed by univariate logistic regression analysis. The prevalence of nonsyndromic craniosynostosis was 3.1 in 10,000 live births in Victoria. On average, the incidence of nonsyndromic craniosynostosis increased by 2.5% per year among Victorian live births. Over 25 years, metopic synostosis incidence significantly increased by 7.1% per year in the population of Victoria, outpacing other subtypes. The risk factors for metopic synostosis include being male, multiple births (ie, twins), preterm gestation, low birth weight, high maternal age, and emergency cesarean birth. This study revealed a true increase in incidence of metopic synostosis in Victoria, which could be a result of increased frequency of multiple births, preterm gestation, low birth weight, and high maternal age in the Victorian population from 1982 to 2008. The incidence of other nonsyndromic craniosynostoses, which include sagittal, unicoronal, and multisutural craniosynostoses, however, has remained unchanged.

A Cephalometric Analysis of Maxillary and Mandibular Parameters in Treacher Collins Syndrome

Background: Treacher Collins syndrome is an autosomal dominant condition of varying severity, affecting the tissues of the first and second branchial arches. The aim of this article is to present a cephalometric analysis of the craniofacial skeleton in Treacher Collins syndrome and provide an age- and sex-matched comparison as a standard control sample. Methods: Twenty-four Treacher Collins syndrome patients (11 male patients and 13 female patients; mean age, 17.99 ± 1.96 years) underwent cephalometric studies, including orthopantomography and lateral and anteroposterior cephalography, as part of their preparation for bimaxillary surgery. Cephalometric parameters assessing the relationships of the skull base, maxilla, and mandible were analyzed and compared with age- and sex-matched control data (mean age, 17.75 ± 1.95 years). Results: Cephalometric analysis before orthognathic surgery documented that the Treacher Collins syndrome mandible and midface are expectedly short in the anteroposterior plane; however, the ratio of maxillomandibular deficiency is particularly significant in the female patient. The mandibular plane angle is obtuse, affecting female patients in particular, in whom there is also a posteriorly placed chin point. Affected individuals have a high antegonial notch height. Although the parameters of anterior lower facial height proportion in control and syndrome individuals are similar, posterior face height in Treacher Collins syndrome is reduced. Conclusions: This study quantifies the cephalometric dysmorphology of patients with Treacher Collins syndrome and compares it to that of age-matched controls. These cephalometric characteristics have clinical significance in Treacher Collins syndrome and in the planning of bimaxillary advancement and genioplasty in syndrome patients.

Submucous cleft palate: an often-missed diagnosis.

AbstractThis study aimed to investigate the age at diagnosis, palatal characteristics, and symptoms of submucous cleft palate (SMCP) and to compare the speech outcomes between 3 operative techniques for primary repair of SMCP.It was a retrospective review of 92 patients diagnosed with SMCP between 1994 and 2008, where patients were treated with 1 of 3 surgical procedures: double opposing z-palatoplasty, radical intravelar veloplasty, or pharyngeal flap.The need for a second procedure was considered a primary outcome measure, with operative failure defined by the need for a secondary operation. Postoperative speech was evaluated perceptually using the Great Ormond Street Speech Assessment.We found that SMCP was diagnosed at a mean age of 3.6 years. At diagnosis, 8% were asymptomatic, 67% had abnormal speech, 49% had recurrent otitis media with effusions, and 47% had hearing loss. Ear, nose, and throat surgery was performed on 37% without the diagnosis of SMCP being made. Subjective impression of a short palate was a predictor for secondary surgery (P < 0.02). Age at repair did not affect velopharyngeal insufficiency outcome; however, repair after 18 months of age led to a higher likelihood of developing articulatory speech errors resulting in the need for more speech therapy.In conclusion, the triad of features of SMCP is well recognized, but our study reveals that a high percentage is seen by physicians who have failed to make the diagnosis despite signs and symptoms being evident. Surgical correction is successful regardless of technique and age, but earlier recognition to prevent speech impairment should be sought.

Total cranial vault remodeling for isolated sagittal synostosis: part I. Postoperative cranial suture patency.

Background: Total vault reconstruction addresses all phenotypic aspects of scaphocephaly. The clinical implications of remodeling across open cranial sutures, however, remain unclear. The purpose of this study was to assess patency of unaffected sutures following total vault remodeling for isolated sagittal synostosis. Methods: The authors reviewed routine postoperative computed tomographic scans of patients who underwent total vault remodeling for isolated sagittal synostosis between 2004 and 2008. Sutural patency was scored by a single reviewer as follows: 0 = closed, 1 = partial, and 2 = open. Individual suture scores were tallied for a total sutural patency score. Computed tomographic scans were stratified by postoperative time and craniofacial surgeon. Results: Forty-two patients met the inclusion criteria. Individual sutural closure rates were 42.6, 38.3, 74.5, and 74.5 percent for right coronal, left coronal, right lambdoidal, and left lambdoidal sutures, respectively. Lambdoidal sutures had a significantly higher rate of closure than coronal sutures (ORClosure, 4.3; 95 percent CI, 2.3 to 8.0; p < 0.001); lambdoidal patency significantly changed over time (&khgr;2 = 9.9, p = 0.04). Across craniofacial surgeons, coronal and lambdoidal patency were equivalent. The total sutural patency score did not significantly correlate with postoperative time, surgical age, preoperative cephalic index, or craniofacial surgeon. Conclusions: Total vault remodeling for isolated sagittal synostosis results in a high degree of secondary craniosynostosis. Lambdoidal sutures are especially prone to closure, with their patency diminishing over time. At this time, radiographic fusion of adjacent sutures following surgery has not been related to any difference in head shape. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Secondary effects of botulinum toxin injections into salivary glands for the management of pediatric drooling.

Abstract This study aimed to assess the secondary benefits and adverse effects of botulinum toxin A injections into the parotid and submandibular glands in children with developmental disability and to determine whether these effects are related to reduction in drooling. Twenty-six children were injected (14 boys and 12 girls; mean age, 11 years 3 months). The Drooling Impact Scale and a secondary effects questionnaire covering aspects of eating, speech, saliva management, and sleep, were administered to the main carer at specific times before and after injection. Group mean preinjection and postinjection item and domain scores were compared using paired t tests. Change scores were calculated; individually categorized as improvement, no change, or deterioration; and related to change in drooling scores using linear regression analysis. Over 4 weeks, evidence of improvement was seen for the entire group with respect to drooling (P < 0.001), eating (P = 0.05), speech (P = 0.04), and sleep (P = 0.01), but not saliva management. Conversely, a minority of families reported worsening of eating skills after the injections that was directly related to lack of improvement in drooling. Because a minority of children unpredictably experience temporary adverse effects after botulinum toxin A injections into the salivary glands, swallowing function and nutritional status should be taken into account before proceeding with treatment.

Three patterns of fronto-orbital remodeling for metopic synostosis: comparison of cranial growth outcomes.

Background: The authors compared cranial growth across three patterns of fronto-orbital remodeling for metopic synostosis. Methods: The authors reviewed all patients who underwent fronto-orbital remodeling for isolated metopic synostosis between 2006 and 2009. Inclusion criteria consisted of patients with preoperative, short-term postoperative (4 to 12 months), and long-term postoperative (>36 months) three-dimensional photographs. Patients were categorized by fronto-orbital remodeling pattern: group 1, retrocoronal; group 2, partial coronal; and group 3, precoronal. Head circumference, minimum frontal breadth (ft-ft), and maximum cranial length were measured by three-dimensional photographs, converted to standard Z scores, and compared. Results: Thirty-one patients met inclusion criteria (group 1, n = 12; group 2, n = 10; and group 3, n = 9). Group 1 presented with the greatest phenotypic severity. From preoperative to short-term postoperative assessment, head circumference Z scores rose for group 1 but dropped for groups 2 and 3, and the three groups demonstrated equivalent increases in minimum frontal breadth Z scores. From short-term to long-term postoperatively, the three groups demonstrated similar stability in head circumference Z scores but decreased minimum frontal breadth Z scores. From preoperatively to long-term postoperatively, head circumference Z scores rose for group 1 but fell for groups 2 and 3 (change in Z score, 0.5, −0.5, and −0.7, respectively; p = 0.06) and the three groups demonstrated equivalent drops in minimum frontal breadth Z scores. Across preoperative to short-term postoperative and preoperative to long-term postoperative assessment, group 1 displayed the least drop in maximum cranial length Z scores. Conclusions: Retrocoronal patterns of fronto-orbital remodeling provide long-term gains in head circumference percentile and the least growth impairment in cranial length. Irrespective of osteotomy design, expansion in frontal breadth relapses significantly over time. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Dentigerous cyst after distraction osteogenesis of the mandible.

Damage to the dentition or tooth follicle is often cited as a potential complication of Distraction Osteogenesis (DO). The authors describe a case of a dentigerous cyst that developed following DO of the mandible. The possible histogenic mechanisms and the management are outlined. Understanding the causes of dentigerous cysts as well as the anatomy of the neonatal mandible may help avoid such a complication in the future.

Computed tomography-based morphometric analysis of extended strip craniectomy for sagittal synostosis.

BackgroundThe purpose of this study is 2-fold: (1) to identify computed tomography (CT)–based morphometric parameters that differentiate the normal skull from one with sagittal synostosis and (2) to evaluate correction of sagittal synostosis with extended strip craniectomy and postoperative helmeting based on morphometric parameters. MethodsAn institutional review board–approved, retrospective review was carried out at the Hospital for Sick Children for all patients who underwent an extended strip craniectomy and postoperative helmeting for sagittal synostosis from 1999 to 2005. Inclusion criteria consisted of patients who underwent a routine craniofacial CT preoperatively and 12 months postoperatively. Craniofacial CT scans of age-matched control subjects were used for preoperative and postoperative comparison. ResultsThirty-nine patients with sagittal synostosis met inclusion criteria. Median age at preoperative CT was 3.0 months. Nine control subjects were identified, with a median age at CT scan of 5.0 months. Patients with sagittal synostosis preoperatively had a significantly longer maximum cranial length, smaller maximum cranial breadth, more acute frontal takeoff and occipital incline angles, lower cephalic index, and an anteriorly positioned vertex. Postoperative CT scans (median, 17.0 months) were compared with 10 control subjects (median, 19.0 months). Patients with sagittal synostosis postoperatively had equivalent maximum cranial breadth, frontal takeoff, and occipital incline angles as compared with controls. Sagittal synostosis patients remained with a significantly longer maximum cranial length, lower cephalic index, and anteriorly positioned vertex. ConclusionsTwelve months following extended strip craniectomy and helmeting for sagittal synostosis, CT-based morphometric analysis demonstrated correction of cranial breadth, frontal bossing, and occipital bulleting. Skull length and vertex position did not fully correct.