All the patients of either gender, diagnosed as a case of acromegaly scheduled for pituitary surgery will be enrolled. This observational study will be conducted over a period of 3 years. A written informed consent will be taken from all the patients. The clinical diagnosis will be made on the basis of growth hormone (GH) levels and magnetic resonance imaging (MRI) findings. All patients will be evaluated preoperatively, a day before surgery by an independent observer. Airway assessment for difficult intubation will be performed using Modified Mallampati classification in sitting and supine position followed by mouth opening, upper lip bite test, measurement of thyromental, thyrohyoid, sternomental and hyomental distance. Next the length of upper incisors, presence of receding mandible and neck movement will be checked. An associated history of OSA will also be taken in to account for assessing the difficult intubation followed by OSA grading in acromegalic patients posted for pituitary surgery. In situation of difficult tracheal intubation the fiberoptic intubation would be the preferred choice, which is a gold standard.