Steven J. Kasten

Local and regional flap closure in myelomeningocele repair: a 15-year review

PurposeA trend in large myelomeningocele defect repair involves soft tissue closure with muscle and fascial flap techniques to provide a durable, protective, and tension-free soft tissue covering. We propose that composite tissue closure yields superior outcomes regardless of defect size.MethodsWe present a retrospective review of our 15-year, single-institution experience using this approach. Our study includes 45 consecutive patients treated using combinations of muscle and fascia flaps for primary closure of a myelomeningocele defect.ResultsLumbosacral fascia closures were used in 18 cases (40%) with paraspinous muscle closure and 12 cases (27%) without paraspinous closure. Fascial closure with bony pedicle periosteum and gluteal muscle and fascial closure were used in four cases (9%) each. Other techniques included latissimus dorsi flaps and combinations of these techniques. Postoperatively, none of our patients experienced a cerebrospinal fluid leak, and only one patient required reoperation for skin flap necrosis.ConclusionsObjective measures show that universal application of flap techniques may lead to better outcomes for soft tissue closure during myelomeningocele repair.

Obstructive sleep apnea after dynamic sphincter pharyngoplasty

IntroductionIn patients who require additional surgery for velopharyngeal insufficiency (VPI), a higher incidence of obstructive sleep apnea (OSA) may be incurred. Although this phenomenon has been demonstrated with the posterior pharyngeal flap, the effect of dynamic sphincter pharyngoplasty (DSP) on OSA is less clear. The purposes of this case series were to (1) determine the incidence of OSA after DSP, (2) assess the changes in polysomnography after DSP, and (3) identify risk factors for the development of OSA after DSP. Our global hypothesis is that OSA and VPI exist on a continuum and that speech outcomes should not be considered in isolation. MethodsFor a 13-year period, 146 patients with idiopathic VPI, submucous cleft palate, cleft palate only, or cleft lip and palate underwent DSP for VPI. The diagnosis of OSA was defined as the prescription of continuous positive airway pressure therapy by a pediatric sleep medicine physician. The incidence of OSA preoperatively and postoperatively was compared using Fisher exact test. When available, preoperative and postoperative apnea–hypopnea indices (AHIs) were compared using the pairwise, 2-tailed, Student’s t-test. Patient factors, such as obesity (body mass index ≥ 95th percentile), the presence of a craniofacial syndrome, surgical history, and a preexisting OSA diagnosis, were noted. A multiple logistic regression was performed to elucidate risk factors for the development of OSA. ResultsThe average age at surgery was 9.2 years (range, 4–40 y), and the mean follow-up time was 4.5 years (range, 1 mo to 12 y). The incidence of OSA increased after DSP, from 2 to 33 patients (1.4%–22%, respectively; P = 0.05). In 23 patients (16%), both preoperative and postoperative AHIs were available. There was a significant increase in AHI after DSP, from 3.1 to 8.4 episodes per hour of sleep (P = 0.001). Previous tonsillectomy/adenoidectomy was predictive of OSA after DSP (relative risk = 2.4; P = 0.04). ConclusionsWe report an increased incidence of OSA and higher-than-average AHIs postoperatively after DSP. Preoperative tonsillectomy/adenoidectomy predicted the development of OSA after DSP. A high index of suspicion for development of OSA must be maintained in patients who undergo secondary speech operations for VPI. Clinical screening for OSA should be used in this population, with a low threshold for polysomnographic evaluation. The surgeon must be wary that improvements in speech after DSP may change airway dynamics and increase the risk of OSA.

A retrospective analysis of revision sphincter pharyngoplasty.

This retrospective study was undertaken to determine the revision rate for dynamic sphincter pharyngoplasty (DSP) at the University of Michigan Medical Center to analyze the determinants contributing to the need for revision pharyngoplasties, and ultimately to improve primary pharyngoplasty to avoid the need for revision. The records of 30 children with repaired palatal clefts who presented with velopharyngeal insufficiency and hypernasal speech, and who underwent DSP from January 1988 through July 1994 were reviewed. Clinical follow-up ranged from 6 to 48 months (mean, 20.2 months). Seven of the original 30 patients (23%) had persistent, moderate-to-severe hypernasality that required reoperation, while 1 patient (3%) demonstrated hyponasality requiring revision. Seven of 8 patients who underwent revision pharyngoplasty had acceptable speech after revision. Dehiscences, low-lying pharyngoplasty flaps, and end-to-end suturing of the flaps were the main determinants resulting in the need for revision. In our study, female gender and older age was associated with a higher success of primary operation.

Survey says? A primer on web-based survey design and distribution.

Summary: The Internet has changed the way in which we gather and interpret information. Although books were once the exclusive bearers of data, knowledge is now only a keystroke away. The Internet has also facilitated the synthesis of new knowledge. Specifically, it has become a tool through which medical research is conducted. A review of the literature reveals that in the past year, over 100 medical publications have been based on Web-based survey data alone. Because of emerging Internet technologies, Web-based surveys can now be launched with little computer knowledge. They may also be self-administered, eliminating personnel requirements. Ultimately, an investigator may build, implement, and analyze survey results with speed and efficiency, obviating the need for mass mailings and data processing. All of these qualities have rendered telephone and mail-based surveys virtually obsolete. Despite these capabilities, Web-based survey techniques are not without their limitations, namely, recall and response biases. When used properly, however, Web-based surveys can greatly simplify the research process. This article discusses the implications of Web-based surveys and provides guidelines for their effective design and distribution.

Posterior pharyngeal fat grafting for velopharyngeal insufficiency.

Objective To determine if autologous fat grafting to the posterior pharynx can reduce hypernasality in patients with cleft palate and mild velopharyngeal insufficiency (VPI). Design Retrospective case series. Setting Tertiary care center. Patients Eleven patients with cleft palate status after palatoplasty (with or without secondary speech surgery) with nasendoscopic evidence of VPI. Interventions Autologous fat was harvested and injected into the posterior pharynx under general anesthesia. Main Outcome Measures Pre- and postoperative subjective, nasometry, and nasendoscopy data. Apnea-hypopnea indices (AHIs) were also assessed. Comparisons were made using Fishers exact test, Students t tests, and relative risk (RR) assessments. Results An average of 13.1 mL of fat was injected (range: 5 to 22 mL). Mean follow-up was 17.5 months (range: 12 to 25 months). Statistically significant improvements in speech resonance were identified in nasometry (Zoo passage; p = .027) and subjective hypernasality assessment (p= .035). Eight of the patients (73%) demonstrated normal speech resonance after posterior pharyngeal fat grafting (PPFG) on subjective or objective assessment (p = .001). All five patients with previous secondary speech surgeries demonstrated normal speech resonance on similar assessment (RR = 1.8; p = .13). Complete velopharyngeal closure was observed in seven patients on postoperative nasendoscopy. No changes in AHIs were observed (p=.581). Conclusion PPFG may be best used as an adjunct to secondary speech surgery. In this series, PPFG was not accompanied by the negative sequelae of hyponasality, sleep apnea, or airway compromise.

Hemangiomas and Vascular Malformations of the Head and Neck: A Simplified Approach

This article is a review of vascular tumors and malformations that occur in infancy and childhood. It discusses anomalies of arterial, venous, capillary, lymphatic, and mixed vascular endothelium in terms of their varying forms, clinical course, imaging characteristics, complications, and treatment. The comparative utility of various imaging modalities is simplified.

Endovascular Methods for the Treatment of Vascular Anomalies

Vascular malformations are congenital lesions secondary to errors in the development of arteries, capillaries, veins, or lymphatics. Most of these lesions are sporadic; however, a certain percentage present with syndromes. This article discusses the clinical features, natural history, and epidemiology of these lesions, and the diagnostic imaging features of vascular anomalies of the head and neck are presented. The percutaneous/endovascular treatment of each of the vascular anomalies is described, and surgical and additional treatment options are discussed briefly. The clinical outcomes of the main forms of treatment and level of evidence are presented.

Assessment challenges in competency-based education: A case study in health professions education

Abstract There is a growing demand for health sciences faculty with formal training in education. Addressing this need, the University of Michigan Medical School created a Master in Health Professions Education (UM-MHPE). The UM-MHPE is a competency-based education (CBE) program targeting professionals. The program is individualized and adaptive to the learner’s situation using personal mentoring. Critical to CBE is an assessment process that accurately and reliably determines a learner’s competence in educational domains. The program’s assessment method has two principal components: an independent assessment committee and a learner repository. Learners submit evidence of competence that is evaluated by three independent assessors. The assessments are presented to an Assessment Committee who determines whether the submission provides evidence of competence. The learner receives feedback on the submission and, if needed, the actions needed to reach competency. During the program’s first year, six learners presented 10 submissions for review. Assessing learners in a competency-based program has created challenges; setting standards that are not readily quantifiable is difficult. However, we argue it is a more genuine form of assessment and that this process could be adapted for use within most competency-based formats. While our approach is demanding, we document practical learning outcomes that assess competence.

Quantitative posture analysis of 2D, 3D, and optical microscope visualization methods for microsurgery tasks.

The purpose of this paper is to present a quantitative posture analysis of microsurgery tasks performed with different visualization methods. Microsurgery is traditionally performed using a binocular microscope; however surgeons are constrained by the optical eyepieces and are forced to assume joint angles that deviate away from neutral postures. This may be especially problematic for the neck and can increase surgeon discomfort and fatigue. Alternative visualization methods may improve surgeon posture by eliminating the constraints imposed by the microscope. This study examines both 2D and 3D heads-up displays as possible alternatives. Six subjects performed microsurgical tasks with each visualization methods for four hours. Quantitative posture analysis was done using Maxtraq software that tracks reflective markers on the subjects. The initial analysis of neck, upper arm, and elbow angles found significant differences between each display. A biomechanical analysis found that the differences in angles can result in loads on the neck joint that are twice as high in the microscope than the headsup displays. Although the alternative displays can result in better postures, improvements the display technology is needed to improve microsurgical task performance.

Effect of alternative video displays on postures, perceived effort, and performance during microsurgery skill tasks

Physical work demands and posture constraint from operating microscopes may adversely affect microsurgeon health and performance. Alternative video displays were developed to reduce posture constraints. Their effects on postures, perceived efforts, and performance were compared with the microscope. Sixteen participants performed microsurgery skill tasks using both stereo and non-stereoscopic microscopes and video displays. Results showed that neck angles were 9-13° more neutral and shoulder flexion were 9-10° more elevated on the video display than the microscope. Time observed in neck extension was higher (30% vs. 17%) and neck movements were 3x more frequent on the video display than microscopes. Ratings of perceived efforts did not differ among displays, but usability ratings were better on the microscope than the video display. Performance times on the video displays were 66-110% slower than microscopes. Although postures improved, further research is needed to improve task performance on video displays.