Diagnostic Validation of Drug-Induced Sleep Endoscopy (DISE)

Drug-induced sleep endoscopy (DISE) was developed in 1991 as a technique to characterize
upper airway collapse in patients with OSA. With the advent of various upper airway surgeries
introduced in recent years, DISE has become increasingly utilized by the sleep surgeon as a
surrogate for airway collapse during natural sleep in order to tailor a surgical approach for
each patient. Propofol and/or midazolam infusions are typically used for sedation in these
cases, however, there is limited evidence to suggest that these anesthetics reproduce natural
sleep architecture. Therefore, it cannot be assumed that the pattern of collapse observed
during DISE is reflective of natural sleep.

The aim of this study is to validate whether the pattern of collapse recorded during DISE
mirrors that of natural sleep. Furthermore, the investigators aim to develop a quantitative
in vivo model for airway collapse in order to further our understanding of the
pathophysiology of OSA. They will do this by comparing the findings from DISE with
aerodynamic readings from within the upper airway during natural sleep. The proposed
technique will employ technologies already approved by the FDA for clinical use. Capacitance
circuitry, airflow sensors, and/or pressure transducers will be suspended within the upper
aerodigestive tract along a thin, low-profile, and flexible tube. During Phase I of the
study, this aerodynamic probe will be placed in the OR during DISE along the upper airway,
namely in the retropalatal, retroglossal, and hypopharyngeal regions. Readings will be
correlated and calibrated with DISE findings in real-time. During Phase II, these sensors
will again be placed within the same patients during in-office sleep studies. The results
from the sleep study will be analyzed in conjunction with OR findings in order to create an
aerodynamic model for natural sleep. This will also allow the investigators to assess whether
airway observations during DISE were valid representations of natural sleep.

Inclusion Criteria:

- Patients with moderate to severe OSAS

- Must have symptoms of OSAS

- Must have sleep study showing AHI of 15 or greater

- Failed trial of CPAP

- BMI less than 35

- Be a surgical candidate for ablative or neuro-stimulation surgery

- Acceptable surgical comorbidities

- Non-aberrant upper airway anatomy

- Must demonstrate reliability in keep appointments

Exclusion Criteria:

- Prior ablative airway surgeries

- Allergies to oxymetazoline or lidocaine

- Significant central sleep apnea

- Presence of other sleep disorders

- History of neurologic or neuromuscular disease

- Historical or present substance abuse

- Bleeding disorders

- Autoimmune diseases that increase risk of nasal trauma such as Wegener's, Sarcoidosis,
etc.

- Pregnancy

- Unacceptable anesthesia risk

- Ablative or orthognathic airway surgery

- Significant weight loss or weight gain with or without bariatric surgery

- Initiation of new drug that is known to alter sleep architecture

- Development of head and neck neoplasm

- Development of autoimmune disease altering airway anatomy

- Trauma to head and neck region