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Functional Endoscopic Sinus Surgery


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Functional endoscopic sinus surgery enlarges pathways to the sinuses. It is done using a special tube that can be passed through the nose.

Reasons for Procedure

The sinuses are hollow areas in the skull that are arranged in pairs. Mucus and other fluids regularly drain from the sinuses through small pathways to the throat. Blockage of these pathways can cause fluids to build up in the sinuses. This can cause pain and infections.

Sinus Infection

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Functional endoscopic sinus surgery opens the pathways for drainage. It may be done for people who have recurring sinus infections that have not responded to other treatment options. Most experience excellent outcomes with this surgery.

Possible Complications

Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like:

  • Excess bleeding
  • Infection
  • Adverse reaction to anesthesia
  • Damage to the optic nerve
  • Spinal fluid leakage
  • Bruising
  • Narrowing of the tear duct

Smoking may increase the risk of complications.

Talk to your doctor about these risks before the procedure.

What to Expect

Prior to Procedure

To make sure you are ready for surgery, your doctor may do the following:

  • Physical exam and medical history
  • Nasal examination
  • Blood tests

Talk to your doctor about your medications. You may be asked to stop taking some medications up to 2 weeks before the procedure.

Before the procedure, you should:

  • Arranging for a ride home from the hospital.
  • Arrange for help at home as you recover.
  • Eat a light meal the night before your surgery. Do not eat or drink anything after midnight unless told otherwise by your doctor.
  • Talk to your doctor if you take any medications, herbs, or supplements.


Local anesthesia will be used to numb the area. If general anesthesia is used, you will be asleep during surgery.

Description of the Procedure

This procedure is usually done in an outpatient setting with no need for an overnight stay. This surgery does not usually require incisions.

A thin tube called an endoscope will be inserted into your nose. Your doctor can view the inside of your nose with this scope. Other surgical tools are passed through the nose to remove abnormal tissues and open the sinus pathways. Your nose may be packed with dressing and/or splints.

How Long Will It Take?

2-4 hours

Will It Hurt?

You will have mild swelling and discomfort. Ask your doctor about pain medication.

Post-procedure Care

At Home

When you return home, take these steps:

  • If your job involves heavy lifting, you may need to stay out of work up to 2 weeks.
  • Be sure to follow your doctor’s instructions.

Call Your Doctor

Call your doctor if any of these occurs:

  • Signs of infection, including fever and chills
  • Redness, swelling, increasing pain, excessive bleeding, or discharge from the nose
  • Pain that you cannot control with the medications that you have been given
  • Nausea and vomiting
  • Lightheadedness
  • Bruising around the eye(s)
  • Swelling of the eye(s)
  • Changes in vision
  • A headache that lasts longer than 2 days after surgery

If you think you have an emergency, call for emergency medical services right away.


American Academy of Otolaryngology—Head and Neck Surgery

Family Doctor—American Academy of Family Physicians


Canadian Society of Otolaryngology—Head and Neck Surgery

The College of Family Physicians of Canada


Fact sheet: sinus surgery. American Academy of Otolaryngology—Head and Neck Surgery website. Available at: Accessed November 28, 2017.

Functional endoscopic sinus surgery. UNC School of Medicine website. Available at: Updated 2002. Accessed November 28, 2017.

Functional endoscopic sinus surgery (FESS). The Children’s Hospital of Philadelphia website. Available at: Updated February 2009. Accessed November 28, 2017.

Slack R, Bates G. Functional endoscopic sinus surgery. Am Fam Physician. 1998 Sep 1;58(3):707-718.

Last reviewed November 2018 by EBSCO Medical Review Board James Cornell, MD  Last Updated: 12/20/2014