In recent years, Snoring and Obstructive Sleep Apnea Syndrome (OSAS) has emerged as an important public health problem. Sleep related breathing disorders are known to cause sleep deprivation, resulting in daytime drowsiness and lack of concentration. It also causes significant psychological and social damage to the sufferers. The first  landmark  epidemiologic study by  Young in 1993 showed that prevalence of OSAS was 3% and 7% of  middle aged women and men  respectively. Snoring is the most common result of the changes in the properties of the upper airway that occur during  sleep.  

Airway shape and size are critical to the air flow. Nasal obstruction have an effect in severity of OSA.Evaluation of the upper airway has indubitably contributed to the understanding of the pathophysiology of snoring and OSAS. It additionally helps us to identify the subjects with increased risk as well as to select an appropriate modality of treatment, especially for surgical procedures. Today there are many subjective and objective test available to diagnose and assess the severity of sleep related breathing disorders . This questionnaire assesses on a numerical scale the likelihood of the patient falling asleep in a given set of real life situations.  

Polysomnography is the gold standard for diagnosing OSAS. Flexible Fiber optic Nasopharyngolaryngoscopy with Muller’s maneuver, an outpatient procedure, is used to detect the collapse of upper airway in awake state. Sleep MRI is an investigation which gaining popularity because of its precise localization of obstruction in OSAS. MR imaging and computer based analysis techniques allows objective quantification of the tongue, soft palate, parapharyngeal fat pads, and lateral pharyngeal walls.