Endonasal transnasal pituitary surgery, also known as endonasal endoscopic intrasphenoidal surgery, is a nasal procedure used to remove tumors from the pituitary gland and the skull base. In this minimally invasive procedure, the surgeon uses a tiny endoscopic camera and light to remove tumors from the nostrils using lengthy probes.

The Process involves the following steps:-

1. Preparation: When the patient is ready for surgery, which may need general anesthesia or sedation. Nasal decongestants can be used to minimize edema of the nasal mucosa.

2. Nasal access: Instead of cutting back, the surgeon approaches the pituitary gland via the natural nose. It is commonly done with an endoscope, which is a thin, flexible tube with a light and camera attached to the end.

3. Sphenoid sinus opening: The surgeon creates a small opening in the posterior wall of the sphenoid sinus, which is located behind the nose. This offers a direct route to the pituitary gland.

4. Endoscopic access: The endoscope is cautiously inserted through the nose and guided to the pituitary gland.

5. Imaging and treatment: The surgeon utilizes endoscopy to see the pituitary gland and its surrounding tissues. Surgical instruments can be used through endoscopy or other small incisions to remove tumors, and cysts, and treat other disorders affecting the pituitary gland.

6. Closure: After making the necessary channels, the sphenoid sinus is closed, and the nasal passages are allowed to recover spontaneously.

Advantages of endoscopic transnasal pituitary surgery include reduced trauma to surrounding structures, shorter recovery time, and fewer scars, and this technique is often used for conditions such as pituitary tumors, cysts, and other abnormalities affecting the tissue.