Does Rapid Eye Movement Sleep Aggravate Obstructive Sleep Apnea?

OBJECTIVES.: To investigate the apnea-hypopnea index (AHI) according to the sleep stage in more detail after control of posture. METHODS.: Patients who underwent nocturnal polysomnography between December 2007 and July 2018 were retrospectively evaluated. Inclusion criteria were as follows: age >18 years, sleep efficacy >80%, and patients who underwent polysomnography only in the supine position (100% of the time). Patients were classified into different groups according to the methods: the first, rapid eye movement (REM)-dominant group (AHIREM/AHINREM >2), non-rapid eye movement (NREM)-dominant group (AHINREM/AHIREM >2), and non-dominant group; and the second, light sleep group (AHIN1N2>AHISWS) and slow wave sleep (SWS) group (AHISWS>AHIN1N2). RESULTS.: A total of 234 patients (mean age, 47.4±13.9 years) were included in the study. There were 108 patients (46.2%) in the REM-dominant group, 88 (37.6%) in the non-dominant group, and 38 (16.2%) in the NREM-dominant group. The AHI was significantly higher in the NREM-dominant group than in the REM-dominant group (32.9±22.9 events/hr vs. 18.3±9.5 events/hr, respectively). There were improvements in the AHI from stage 1 to SWS in NREM sleep with the highest level in REM sleep. A higher AHISWS than AHIN1N2 was found in 16 of 234 patients (6.8%); however, there were no significant predictors of these unexpected results except AHI. CONCLUSION.: Our results demonstrated the highest AHI during REM sleep stage in total participants after control of posture. However, there were 16.2% of patients showed NREM-dominant pattern (AHINREM/AHIREM >2) and 6.8% of patients showed higher AHISWS than AHIN1N2. Therefore, each group might have a different pathophysiology of obstructive sleep apnea (OSA), and we need to consider this point when we treat the patients with OSA.

The Treatment Outcomes of Primary Subglottic Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Primary subglottic cancer is uncommon, so our understanding of primary subglottic cancer is limited. The purpose of this study is to review the clinical characteristics and treatment result of primary subglottic cancer from our experience. SUBJECTS AND METHOD: During the period from Nov. 1996 to Nov. 2010, patients with primary subglottic cancer were reviewed retrospectively. The mean follow up period was 46.1+/-40.9 months. We analyzed its clinical characteristics, stage, treatment results and survival rate. RESULTS: Of 824 patients with diagnosed laryngeal cancer, 8 (0.97%) had primary subglottic cancer and hoarseness (50.0%) is the most common initial presenting symptom. The symptom of dyspnea was found in 25.0% (2/8) of the patients and squamous cell carcinoma in 75% (6/8). At the time of diagnosis, the four clinical stages of TNM, T1, T2, T3 and T4, had 1 (12.5%), 2 (25.0%), 1 (12.5%) and 4 (50.0%) patients, respectively. There were two cases of cervical lymph node metastases, N1 and N2c. No distant metastasis was found. Two groups of patients comprising of two patients each received surgery alone or radiation alone as an initial treatment; another two groups of patients comprising of two patients each received concurrent chemoradiation or surgery plus radiation therapy alone. The overall 2-year survival rate was 80.0% and 2-year disease free survival rate was 51.7% in patients with squamous cell carcinoma. CONCLUSION: Despite the infrequency of primary subglottic cancer, it is important to understand its clinical characteristics and treatment results during the early diagnosis to make the prognosis better.

A Case of Bilateral Hearing Loss Following External Ventricular Drainage / 대한이비인후과학회지

The sensorineural hearing loss following extraventricular drainage (EVD) is perhaps an underestimated complication rather than an uncommon event. Changes in the cerebrospinal fluid (CSF) pressure may lead to endolymphatic hydrops through the patent cochlear aqueduct resulting in sensorineural hearing loss. We describe the case of a 9-year-old child suffering from meduloblastoma. Bilateral hearing loss, especially at low frequency was found after emergent extraventricular drainage. At 2 months of treatment, hearing loss improved a little, but not restored to a serviceable hearing. Our experience and a review of articles indicate that early detection and awareness of hearing loss after EVD are important for treatment strategy.