Introduction: The most common cause of sleep disordered breathing is reported to be the obstructive sleep apnoea. It could possibly lead to serious physiological, social and few neurocognitive disorders. Since the reported prevalence rate is higher, OSA has often been misdiagnosed and unnoticed. Materials and Methodology: This study was designed as a retrospective analysis of patients reported with the polysomnographic confirmation of obstructive sleep apnoea. Those patients included in this study had undergone Drug Induced Sleep Endoscopy (DISE) using flexible video rhino-laryngoscope under BISTM monitoring which is reported to be a valid bi-spectral index monitor in measuring the depth of sedation. Drugs like dexmedetomidine and midazolam was initially used in titrating doses in order to maintain BISTM score in the range of 60–80. The DISE video data of 189 patients was assessed by two ENT surgeons individually. Each of them was instructed to grade the hypertrophy of the salpingopharyngeal fold as Grade 0 having normal anatomy, Grade 1 being hypertrophy causing partial obstruction and Grade 2 being hypertrophy which is reportedly responsible for complete obstruction of lateral pharyngeal wall. Data of 160 patients of the 189 had 100% agreement between the two expert surgeons while grading the hypertrophy. Thus, the data of 160 patients was included in the study for further comparison and analyses. The patient’s data was divided into two groups. Group 1 included 110 patients who had isolated palatal level obstruction whereas group 2 constituted 50 patients affected with sleep apnoea due to obstruction at multiple levels BMI of the patient was calculated. There was no significant difference between the two groups for age (p<0.05), AHI (p <0.05) and BMI (p<0.05) Shapiro Wilks test of Normality was applied to check for the distribution of the data, non-normal distribution the data was subjected to non-parametric analyses.