Functional endoscopic sinus surgery is a minimally invasive surgical treatment which uses nasal endoscopes to enlarge the nasal drainage pathways of the paranasal sinuses to improve sinus ventilation. This procedure is generally used to treat inflammatory and infectious sinus diseases, including chronic rhinosinusitis that doesn't respond to drugs, nasal polyps, some cancers, and decompression of eye sockets/optic nerve in Graves ophthalmopathy. In the surgery, an otolaryngologist removes the uncinate process of the ethmoid bone, while visualizing the nasal passage using a fiberoptic endoscope. FESS can be performed under local anesthesia as an outpatient procedure. Generally patients experience only minimal discomfort during and after surgery. The procedure can take from 2 to 4 hours to complete.
History
The first recorded instance of endoscopy being used for visualization of the nasal passage was in Berlin, Germany in 1901. Alfred Hirschmann, who designed and made medical instruments, modified a cystoscope to be used in the nasal cavity. In October 1903, Hirschmann published "Endoscopy of the nose and its accessory sinuses." In 1910, M. Reichart performed the first endoscopic sinus surgery using a 7 mm endoscope. In 1925, Maxwell Maltz, MD created the term "sinuscopy," referring to the endoscopic method of visualizing the sinuses. Maltz also encouraged the use of endoscopes as a diagnostic tool for nasal and sinus abnormalities. In the 1960s, Harold Hopkins, PhD at Reading University used his background in physics to develop an endoscope that provided more light and had drastically better resolution than previous endoscopes. Hopkins' rod optic system is widely credited with being a turning point for nasal endoscopy. Utilizing Hopkins' rod optic system, Austrian doctor Walter Messenklinger visualized and recorded the anatomy of the paranasal sinuses and the lateral nasal walls in cadavers. Specifically, Messerklinger focused on mapping out mucociliary routes. In 1978, Messerklinger published the book titled "Endoscopy of the Nose" on his findings, and his proposed methods to utilize nasal endoscopy for diagnosis. After learning of Messenklinger's endoscopic techniques, David Kennedy, MD, and Karl Storz, MD, of Johns Hopkins University developed instruments for use in endoscopic sinus surgery, and coined the term Functional Endoscopic Sinus Surgery. Kennedy published multiple papers on FESS use and technique, and in 1985 the first course on FESS was taught at Johns Hopkins Medical Center.
Medical applications
Functional Endoscopic Sinus Surgery is most commonly used to treat chronic rhinosinusitis, only after all non-surgical treatment options such as antibiotics, topical nasal corticosteroids, and nasal lavage with saline solutions have been exhausted. Chronic rhinosinusitis is an inflammatory condition in which the nose and at least one sinus become swollen and interfere with mucus drainage. It can be caused by anatomical factors such as a deviated septum or nasal polyps, as well as infection. Symptoms include difficulty breathing through the nose, swelling and pain around the nose and eyes, postnasal drainage down the throat, and difficulty sleeping. CRS is a common condition in pediatric patients and young adults. The purpose of FESS in treatment of CRS is to remove any anatomical obstructions that prevent proper mucosal drainage. A standard FESS includes removal of the uncinate process, and opening of the anterior ethmoid air cells and Haller cells as well as the maxillary ostium, if necessary. If any nasal polyps obstructing ventilation or drainage are present, they are also removed. In the case of paranasal sinus/nasal cavity tumors, an otolaryngologist can perform FESS to remove the growths, sometimes with the help of a neurosurgeon, depending on the extent of the tumor. In some cases, a graft of bone or skin is placed by FESS to repair damages by the tumor. In the thyroid disorder known as Graves Ophthalmopathy, inflammation and fat accumulation in the orbitonasal region cause severe proptosis. In cases that have not responded to corticosteroid treatment, FESS can be used to decompress the orbital region by removing the ethmoid air cells and lamina papyracea. Bones of the orbital cavity or portions of the orbital floor may also be removed. The endoscopic approach to FESS is a less invasive method than open sinus surgery, which allows patients to be more comfortable during and after the procedure. Entering the surgical field via the nose, rather than through an incision in the mouth as in the previous Caldwell-Luc method, decreases risk of damaging nerves which innervate the teeth. Because of its less-invasive nature, FESS is a common option for children with CRS or other sinonasal complications.
Outcomes and complications
Functional Endoscopic Sinus Surgery is considered a success if most of the symptoms, including nasal obstruction, sleep quality, olfaction and facial pain, are resolved after a 1-2 month postoperative healing period. Reviews of FESS as a method for treating chronic rhinosinusitis have shown that a majority of patients report increased quality of life after undergoing surgery. The success rate of FESS in treating adults with CRS has been reported as 80-90%, and the success rate in treating children with CRS has been reported as 86-97%. The most common complication of FESS is cerebrospinal fluid leak, which has been observed in about 0.2% of patients. Generally, CSFL arises during surgery and can be repaired with no additional related complications postoperatively. Other risks of surgery include infection, bleeding, double vision usually lasting a few hours, numbness of the front teeth, orbital hematoma, decreased sense of smell, and blindness. Blindness is the single most serious complication of FESS, and results from damage to the optic nerve during surgery. Serious complications such as blindness occur in only 0.44% of cases, as determined by a study performed in the United Kingdom. A Cochrane review in 2006 based on three randomized control trials concluded that FESS has not been shown to provide significantly better results than medical treatment for chronic rhinosinusitis. Another Cochrane review looked at postoperative care of patients after FESS using debridement, but the evidence from the available clinical trials was uncertain. The debridement procedure after FESS may make little or no difference to health‐related quality of life or disease severity. There may be a lower risk of adhesions but whether this has any impact on long‐term outcomes is unknown.
