Endonasal Endoscopic Surgery - Procedure, Recovery, and Advancements

Introduction

Endoscopic endonasal surgery refers to using an endoscope (a long thin tube with a camera attached at one end to visualize the inner structures in detail from the outside). The nostrils provide a pathway for direct access to the skull base lesions. It requires a multidisciplinary team of neurosurgeons, otolaryngologists, spine surgeons, and ophthalmologists to operate in these areas without affecting the face or the skull.

What Is Endonasal Endoscopic Surgery?

It is a minimally invasive surgical technique that uses an endoscope to go through the nose and perform surgery in the base of the skull. The lesions at the base of the head were difficult to treat until the invention of the endonasal endoscopic technique. With this advancement, patients with such conditions are cured and able to lead everyday lives.

Who Needs Endonasal Endoscopic Surgery?

The following conditions can be treated with endonasal endoscopic surgery:

• Pituitary gland tumors (the pituitary is an endocrine gland at the base of the skull) and associated conditions like acromegaly (gigantism caused by increased production of the pituitary hormone), Cushing's disease (when the body produces too much of stress hormone) and pituitary apoplexy (bleeding within the non-cancerous pituitary gland tumors) that occurs due to disorders in the gland are treated by the endonasal endoscopic approach.

• Intracranial aneurysm (an abnormality in the blood vessels of the brain).

• Craniopharyngioma (a non-cancerous brain tumor).

• Meningiomas (a tumor of the membrane that surrounds the brain and spinal cord- the meninges).

• Cerebrospinal fluid fistula (a cerebrospinal fluid fistula is a communication between the subarachnoid space and the ear cavity and the cerebrospinal fluid acts as a shock absorber and is present in the subarachnoid space around the brain).

• Schwannoma (a tumor of the nerve sheath or the layer protecting the nerve).

• Rathke’s cleft cyst (a non-cancerous tumor that is present between the pituitary and the base of the brain).

All of the conditions mentioned above are effectively treated through endonasal endoscopic surgery. Most of these conditions are not easily accessible through the standard technique. Hence, the new approach paves the way to overcome these challenges and remove the lesions near the base of the skull.

How to Prepare a Patient for Endonasal Endoscopic Surgery?

Before the surgery, the patient must undergo a few medical tests, and complete medical history is noted.

• The doctor will discuss the surgical procedure, and the patient signs a consent form as a willingness to start the procedure.

• If the patient is an active smoker, the habit must be quit at least two weeks before the surgery for proper healing.

• If the patient is under any medication, such as a blood thinner (Aspirin), it is stopped for a few days with the physician’s consent. Medicines such as vitamin E are also stopped two weeks before the surgery.

• The doctor prescribes medications that the patient has to consume before the procedure.

• Any allergy to the medication or anesthesia is noted to prevent complications after the surgery.

• The patient is advised not to have solid food the day before surgery and drink only water before reaching the hospital.

How Is Endonasal Endoscopic Surgery Performed?

• The procedure is done under general anesthesia to make the patient unconscious and painless during the operation.

• The surgeon introduces the endoscope through the nose and sinuses with the camera and light attached to its end. The light and the camera give a clear view of the site to be operated.

• The instruments specially designed for endonasal surgery are inserted through the nose into the affected area. With a detailed view of the structures present inside, the surgeon can precisely locate and remove the lesion at the base of the skull.

• The nose and sinuses are then closed by bandages.

How Is the Skull Base Reconstructed After the Surgery?

Reconstruction of the skull base is required to prevent cerebrospinal fluid leakage after the surgery. This is mandatory when the surgeon makes a large opening to remove the lesion. The reconstruction must be watertight. The surgeon places a tight barrier for the cerebrospinal fluid, and a synthetic dural substitute (to repair the dural layer beneath the skull bone) is placed over it.

What Are the Complications Associated With Endonasal Endoscopic Surgery?

Any surgery on the body involves numerous risks and complications. It is up to the doctor and the patient to decide how to overcome these complications. The following are the risks involved in the surgery.

• General complications like allergic reactions to anesthesia, bleeding, pain, and blood clot formation.

• The structures in the adjacent area, like the blood vessels or the nerves, may get injured.

• Leakage of the cerebrospinal fluid through the nose.

• Signs of infection at the operated area.

• Recurrence of the lesion necessitating another surgery.

• Delayed healing.

How Is the Recovery After Endoscopic Endonasal Surgery?

Endonasal endoscopic surgery is a safe and suitable procedure for patients with inaccessible lesions at the skull base. The recovery after the surgery is good. The patient is discharged in one or two days from the hospital.

• The nurse monitors the patient for a few days to check the progress of the patient’s condition. The patient is discharged in one or two days from the hospital.

• The bandages placed on the nose and sinuses are removed one week after the surgery.

• All the medications prescribed should be consumed regularly to control the pain and infection.

• Heavy exercises causing strain to the body are avoided for about four to six weeks after the surgery.

• Regular visits to the doctor are followed to maintain the health of the patient post-surgery.

The patient must inform the surgeon if they notice any of the following changes after the surgery:

• Persistent pain.

• High fever.

• Difficulty in breathing.

• Signs of inflammation at the operated site include redness, swelling, and pus discharge.

• Shivering.

• Swelling around the nose.

• Any sign of drainage from the nose.

The doctor is consulted, and the cause for such changes is found and managed immediately.

What Are the Advancements in Skull Base Surgery?

Apart from endonasal endoscopic surgery, a few more advanced techniques are available to treat skull base lesions. One among them is the 3-D (three-dimensional) technique that gives a more in-depth view of the operating site. Other advancements include intraoperative CT (computed tomography) scan, integrated endoscopy, and proton beam therapy.

Conclusion

With new advancements in neurosurgery, endonasal endoscopic surgery is one of the safest and most effective techniques to treat lesions at the base of the skull. It requires a collaborative team of specialists to perform the surgery. The surgeon must be highly skilled and ready to manage complications. The overall outcome is good, and this technique serves as an eye-opener for patients with lesions in the inaccessible areas of the brain.