Michelle S. Hwang

Targeted hypoglossal nerve stimulation for the treatment of obstructive sleep apnea: Six-month results

This feasibility study was designed to show the preliminary safety and efficacy of targeted hypoglossal neurostimulation (THN), and to identify baseline predictors of successful therapy.

A Standardized Lingual Tonsil Grading System Interexaminer Agreement

Objective Comparisons among studies involving the tongue base are limited by lack of a universal system for grading lingual tonsils. The authors propose a new standardized clinical grading system for lingual tonsil hypertrophy (LTH). Validation was assessed via an interexaminer agreement study. Study Design Kappa interrater agreement study. Setting Tertiary academic center. Subjects and Methods Video assessment: The proposed grading system consists of a 0-to-4 scale: 0 = complete absence of lymphoid tissue; 1 = lymphoid tissue scattered over tongue base; 2 = lymphoid tissue covering entirety of tongue base with limited vertical thickness; 3 = significantly raised lymphoid tissue covering entirety of the tongue base, approximately 5 to 10 mm in thickness; 4 = lymphoid tissue rising above the tip of the epiglottis, ≥1 cm in thickness. The vertical height of the tonsils is a clinical approximate. A teaching video demonstrated identification of this grading system. Fourteen trained otolaryngologists graded 20 video clips of the tongue base, recorded during flexible laryngoscopy. Live assessment: A second study was performed by 2 examiners directly examining the tongue base of 23 patients using flexible laryngoscopy. Results Video assessment: The overall Fleiss kappa statistic was 0.775 (P < .0001). This denotes substantial agreement. Live assessment: The overall kappa for nominal data was 0.8665 (P < .0001). This denotes near perfect agreement. Conclusion The substantial interexaminer correlation demonstrated during video assessment and perfect interexaminer correlation in live assessment indicate that the proposed grading system may be a valuable and useful tool in creating a common language to describe lingual tonsils.

Factors Associated with Hypertrophy of the Lingual Tonsils

Objective To identify factors that may be associated with lingual tonsil hypertrophy (LTH). Study Design Case series with chart review. Setting Tertiary academic center. Subjects and Methods Retrospective chart review identified 380 patients from August 2013 to April 2014 with graded lingual tonsils, documented during routine flexible laryngoscopy. Lingual tonsils were graded using a 0 to 4 scale: 0 = complete absence of lymphoid tissue, 1 = lymphoid tissue scattered over tongue base, 2 = lymphoid tissue covers entirety of tongue base with limited thickness, 3 = lymphoid tissue 5 to 10 mm in thickness, 4 = lymphoid tissue >1 cm in thickness (rising above the tip of epiglottis). Reflux symptom index (RSI collected during patient intake), presence of obstructive sleep apnea hypopnea syndrome (OSAHS; confirmed by polysomnogram), smoking habits, and basic demographics were gathered. Chi-square and linear multivariate regression analyses were used to identify significant relationships with LTH levels. Results Overall, 59.8% were male with a mean age of 50.2 ± 16.5 years and BMI of 30.1 ± 18.0. Chi-square analysis revealed no significant relationship between OSAHS and LTH (P = .059). When RSI was stratified to ≥10 or <10, a Cochran-Armitage test supported the trend hypothesis that as RSI increases, lingual tonsil grading increases. Significant univariate correlates included younger age (r = −0.307, P < .001) and smoking (r = 0.186, P = .002). Multivariate regression revealed the combination of younger age, increasing RSI, and smoking (r = −0.297, P < .001) to be a significant correlate. Conclusion LTH does not seem to be associated with OSAHS or BMI in this group of patients. High RSI, younger age, and gender may be factors associated with increased lingual tonsil thickness.

Association Between Obstructive Sleep Apnea and Spontaneous Cerebrospinal Fluid Leaks: A Systematic Review and Meta-analysis

IMPORTANCE Spontaneous cerebrospinal fluid (CSF) leaks are a morbid condition associated with operative intervention for treatment. Understanding associations are key to diagnosis, treatment, and possible early detection. OBJECTIVE To determine the clinical association and odds of having obstructive sleep apnea (OSA) and spontaneous CSF leaks. DATA SOURCES A comprehensive search of the literature was conducted using PubMed (MEDLINE), Cochrane Library, and relevant article bibliographies. STUDY SELECTION Systematic review and meta-analysis of studies from 2005 to 2015 investigating spontaneous CSF leaks in patients with OSA. The CSF leaks were considered spontaneous when they occurred in the absence of trauma, surgery, infection, and neoplasm. Included studies provided the number of patients diagnosed as having OSA and spontaneous CSF leaks. DATA EXTRACTION AND SYNTHESIS Two independent investigators reviewed all studies for inclusion. The numbers of patients with OSA were systematically extracted from each study. Studies that compared the prevalence of OSA with spontaneous CSF leaks against their control cohort were pooled in the meta-analysis using a random-effects model. MAIN OUTCOME AND MEASURE To determine whether there was increased incidence of OSA in patients with spontaneous CSF leaks. This hypothesis was formulated prior to data collection. RESULTS The search criteria yielded 384 abstracts, and 6 clinical studies involving OSA and CSF leaks met the inclusion and exclusion criteria. They were all retrospective in nature and included 3 comparative (case-control) studies, 2 case series, and 1 case report. The cumulative reported prevalence of having OSA and spontaneous CSF leaks is 16.9% (232 of 1376 patients). Three of the studies were eligible for the meta-analysis. The odds of having OSA with a spontaneous CSF leak were 4.73 times more likely than in control cohorts (95% CI, 1.56-14.31; P = .006; I² = 35%). In a subgroup analysis of studies including nonspontaneous CSF leaks as their control cohort, the odds of having OSA with a spontaneous CSF leak were 2.85 times more likely than OSA with a nonspontaneous CSF leak (95% CI, 1.22-6.63; P = .02; I² = 0%). There was a notable difference in the age, BMI, or patients with hypertension in the comparative studies. CONCLUSIONS AND RELEVANCE The association between OSA and spontaneous CSF leaks as demonstrated by retrospective studies is confounded by heterogeneous patient characteristics. Large prospective controlled studies using polysomnography and elevated intracranial pressure measurements are required to further evaluate the relationship between OSA and spontaneous CSF leaks.

Clinical predictors of effective continuous positive airway pressure in patients with obstructive sleep apnea/hypopnea syndrome.

To identify standard clinical parameters that may predict the optimal level of continuous positive airway pressure (CPAP) in adult patients with obstructive sleep apnea/hypopnea syndrome (OSAHS).

Impact of mandibular advancement devices on C-reactive protein levels in patients with obstructive sleep apnea

To determine the effect of treatment of obstructive sleep apnea (OSA) with custom‐made mandibular advancement devices (MADs) on C‐reactive protein (CRP) levels in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS).

What is the evidence for postoperative lumbar drains in endoscopic repair of CSF leaks

BACKGROUND The overall success rate for endonasal endoscopic repair of cerebrospinal spinal fluid (CSF) leaks is high, ranging from 90% for primary repairs to 97% for secondary. With the advancement of vascularized flaps, the rates of postoperative reoccurrence of CSF leaks have decreased. The complication rate is reportedly less than 0.03%; however, when they occur, they can include CSF leak reoccurrence and bacterial meningitis. The role of postoperative lumbar drains (LD) in the endoscopic management of CSF rhinorrhea is currently controversial. Cerebrospinal spinal fluid diversion with a lumbar drain may prevent postoperative intracranial pressure (ICP) elevations that would disrupt the graft closure. However, LD utilization has been associated with increased complication rates of up to 12.3%. These complications include pneumocephalus, persistent headaches, meningitis, uncal herniation, and lumbar radiculopathy.

What is the best management of asymptomatic unilateral tonsillar enlargement

BACKGROUND Lymphoma is the most common pediatric cancer of the head and neck, typically involving the cervical lymph nodes. However, primary tonsillar lymphoma accounts for <1% of head and neck cancer. It is generally believed that tonsillectomy is indicated to treat unilateral tonsillar enlargement (UTE), due to concern for lymphoma in the enlarged tonsil. This is particularly true in the setting of suspicious symptoms such as constitutional symptoms or cervical lymphadenopathy. Yet many patients with isolated UTE, with no associated symptoms, are still treated surgically. However, recent research suggests that treating asymptomatic UTE with tonsillectomy may be unnecessarily invasive, because clinical assessment of asymmetric tonsils may be inaccurate and because very few enlarged tonsils actually contain malignancies.

Provent therapy for obstructive sleep apnea: Impact of nasal obstruction

Determine the impact of nasal obstruction on efficacy, success, and adherence of Provent therapy in patients with obstructive sleep apnea (OSA).

The effect of oral positioning on the hypopharyngeal airway

It is generally assumed that mouth opening decreases the hypopharyngeal cross‐sectional area (HA) and that tongue protrusion (TP) increases the HA. We hypothesize that a substantial number of patients do not exhibit this expected pattern.