Kenneth B. Schechtman

This paper, which has been reviewed and approved by the Board of Directors of the American Sleep Disorders Association, provides the background for the Standards of Practice Committee's parameters for the practice of sleep medicine in North America. The intent of this paper is to provide an overview of the surgical treatment of obstructive sleep apnea syndrome, to provide the basis for the American Sleep Disorders Association's practice parameters on this subject and to share our findings of metanalysis of previously published studies regarding uvulopalatopharyngoplasty. We searched MEDLINE from January 1966 through April 1993, with an update in February 1995, to provide a review of the application of surgical modifications of the upper airway to treat adults with obstructive sleep apnea syndrome. Operations to treat obstructive sleep apnea syndrome include nasal septal reconstruction; uvulopalatopharyngoplasty; uvulopalatopharyngoglossoplasty; laser midline glossectomy; lingualplasty; inferior sagittal mandibular osteotomy and genioglossal advancement, with hyoid myotomy and suspension (the entire process is referred to as GAHM); maxillomandibular osteotomy and advancement, and tracheotomy. Papers included in metanalysis provided preoperative and postoperative polysomnographic data on at least nine patients treated with uvulopalatopharyngoplasty for their obstructive sleep apnea. Analysis of the uvulopalatopharyngoplasty papers revealed that this procedure is, at best, effective in treating less than 50% of patients with obstructive sleep apnea syndrome. The site of pharyngeal narrowing or collapse, although identified by different and unvalidated methods, has a marked effect on the probability of success of uvulopalatopharyngoplasty. Patients who achieve a favorable response with uvulopalatopharyngoplasty tend to have less severe obstructive sleep apnea than those who do not. For patients who demonstrate retrolingual narrowing or collapse, other surgical modifications have been described, such as lingualplasty, GAHM, and maxillomandibular osteotomy and advancement. The studies to support the use of the surgical treatment of obstructive sleep apnea syndrome contain biases related to small sample size, limited follow-up and patient selection.

PURPOSE: The multicenter Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is a prospective, observational study of 1,209 keratoconus patients. We report on the prevalence of corneal scarring in these patients. We also report on the test-retest repeatability of corneal scar documentation at the slit-lamp biomicroscope by trained clinicians and by masked photograph readers and on the scarring-status agreement at baseline between clinicians and photograph readers. METHODS: Clinicians and masked photograph readers graded each cornea as to scarring status. Patients were examined by clinicians, and their corneas were photographed at baseline (2,297 nongrafted eyes of 1,209 patients) and at a repeated visit (258 nongrafted eyes of 138 patients). These photographs were evaluated by the masked readers at the CLEK Photography Reading Center (CPRC). Clinicians reported corneal scars in right eyes at baseline as "definitely not present" in 53.9%, "probably not present" in 8.4%, "probably present" in 8.2%, and "definitely present" in 29.4% of patients. A weighted kappa statistic of 0.83 (95% confidence interval from 0.78 to 0.88) indicates that agreement is excellent between baseline and repeated assessments for the presence of a corneal scar by clinicians. RESULTS: Agreement is very good between baseline and repeated photograph-reader assessments for the presence of a scar, with a weighted kappa of 0.77 (95% confidence interval, 0.72-0.82). The kappa statistic comparing photograph-reader scarring assessments with clinician results was 0.69 (95% confidence interval, 0.66-0.71). CONCLUSION: The data also suggest better agreement between clinicians and readers when Vogt's striae and corneal nerves were observed. The data also suggest better agreement when corneal staining was not observed by the photograph readers. The CLEK Study protocol for determining the presence of scars is highly repeatable.