Varieties of OSA Surgery
While positive airway pressure therapy is the first line of treatment for moderate to severe sleep apnea, patient compliance represents a clear problem. Studies have shown that even in compliant patients, the actual usage of PAP is only approximately 50 percent of the time. Patients often complain of difficulty in being able to wear a tight mask throughout the night and dealing with the high pressure of air blown into their nose. For the noncompliant, surgery for sleep apnea may be a feasible alternative. While there are many surgical options, surgery should be tailored to the area of obstruction in each particular patient. The sites of obstruction could be anywhere in the upper respiratory tract including the nose, tongue, and throat. Below are the most common and effective surgical methods to address these potential sites of obstruction.
Both daytime nasal obstruction and nocturnal nasal congestion have been shown as risk factors for sleep-disordered breathing. Therefore, the treatment of nasal obstruction plays an important role in sleep apnea surgery. Three anatomic areas of the nose that may contribute to obstruction are the septum, the turbinates, and the nasal valve. The most common nasal surgical procedure consists of septoplasty and turbinate reduction. This is an outpatient procedure that is well tolerated by most patients. It consists of straightening out the septum and reducing the size of the turbinates. This procedure creates more room in the nose and allows air to pass smoothly and without effort. For some patients, there is also nasal valve collapse. This is due to weakness of the lower nasal cartilages that hold open the nostrils. For patients who have this issue, the deviated cartilage that is removed from the septum can be strategically placed to strengthen the valve and prevent collapse.
UPPP, or in full, uvulopalatopharyngoplasty, has been the most common sleep apnea surgical procedure performed during the past 25 years. This procedure was developed to remove excess tissue from the soft palate and pharynx. The tonsils are also removed if present. After removing the tissue, sutures are placed to keep the area widely open and prevent collapse. This area of the upper airway is referred as the oropharynx, and is a common site of obstruction in the majority of patients who suffer from sleep apnea. This surgery requires an overnight stay in the hospital, as the recovery can be painful for up to one week. Patients who suffer from snoring gain a great deal improvement from this procedure as snoring is often due to the reverberation of the soft palate with the back wall of the pharynx.
Soft palate implants (the Pillar Procedure)
The Pillar Procedure is a minimally invasive approach that can help with snoring and mild cases of sleep apnea. It involves the placement of three polyester rods into the soft palate. The rods initiate an inflammatory response of the surrounding soft tissues that results in a slight stiffening of the soft palate. The stiffer soft palate is less likely to make contact with the back wall of the pharynx during deep stages of sleep as the muscles relax; snoring and apnea are subsequently reduced. This procedure can be done under local anesthesia in the clinic with the patient awake.
The hyoid bone is a small bone in the neck where the muscles of the tongue base and pharynx attach. Patients with sleep apnea often have a large tongue base. During the deep stages of sleep, normal muscle tone is relaxed, and the base of tongue falls back and can make contact with the back wall of the pharynx resulting in obstruction. Through a very minimally invasive procedure, the hyoid bone is surgically repositioned anteriorly by placing a suture around it and suspending it to the front of the jaw bone. This results in an expansion of the airway and prevents collapse. The procedure is usually performed with two small incisions in the neck and is completed in less than one hour. Patients go home immediately after surgery and pain is minimal. Success from this procedure has been outstanding and is becoming a valuable tool in the surgeon’s armamentarium.
This procedure involves advancing one of the main tongue muscles, the genioglossus muscle, forward; thereby limiting the tongues backward fall during sleep. The genioglossus advancement procedure consists of making a rectangular cut in the jaw bone where the genioglossus muscle attaches. The piece of bone is then moved forward with the muscle attached. The bone is fixed into place with a small titanium plate to prevent retraction back into the floor of the mouth. This procedure addresses the same sites of potential obstruction as the hyoid advancement, and numerous studies have shown a high success rate. This procedure, however, requires an overnight stay in the hospital, as it is more invasive. A less invasive form of advancement involves drawing the tongue forward with a loop of plastic cord that is fastened under the front of the tongue to a titanium screw inserted into the lower jaw bone.
Tongue base reduction
As discussed previously, the base of tongue is a common site of obstruction in patients who suffer from OSA. In addition the advancement procedures, reducing the amount of tissue from the tongue base through a variety of methods is an effective surgical method to reduce apnea. One method is through the application of radiofrequency waves. A surge of energy is introduced to the tissue that results in shrinkage of the tissue. The radiofrequency waves are directed to specific sites in the tongue base without causing surrounding tissue damage. While the procedure is minimally invasive, and can sometimes be done with the patient awake in the clinic, several treatments are necessary. Another method to reduce the tongue base is through direct excision. In this procedure, also known as a midline glossectomy, the tongue base tissue is removed by electrocautery or coblation. This is accomplished under general anesthesia in the operating room and is also tolerated with very little pain. Due to the small, but real risk of airway compromise, patients are observed overnight in the hospital. Studies have shown that all methods of tongue base reduction can be effective when properly employed.
Lower jaw advancement
Abnormality of the maxillofacial skeleton is a well-recognized risk factor of obstructive sleep apnea. Sleep apnea patients usually have small, narrow jaws that result in diminished airway dimension, which leads to nocturnal obstruction. Maxillomandibular advancement achieves enlargement of the entire upper airway through expansion of the skeletal framework that encircle the airway. The procedure consists of mobilizing the upper and lower jaw bones, and advancing then up to 10-12mm. The jaw bones are stabilized with titanium plates in the advanced position. This procedure is technically very challenging as the bone cuts need to be precise, and the positioning of the teeth to match correctly after the advancement is critical. Patients have to have their teeth wired shut for several weeks while the bones heal. While the surgery can be painful and require a several night hospital stay, the long term success rates approach 90 percent Very few surgeons and medical centers perform this procedure frequently due to the increased surgical risks and potential for complications.
Tracheostomy is a technique that creates a passageway for air to get to the lungs directly from the trachea in the neck. This will bypass any potential sites of obstruction from the upper airway. Permanent tracheostomy as a long-term treatment of obstructive sleep apnea remains an option in morbidly obese patients with obesity hypoventilation syndrome or in patients with significant craniofacial anomaly who have failed all other forms of non-surgical and surgical treatments. Though it may seem excessive, it is an extremely effective surgical option reserved for the very sick patient.
There are many surgical options for the treatment of sleep apnea for patients who can not tolerate CPAP therapy. Because the airway pattern and the severity of obstruction vary greatly between individuals, the surgical regimen must be catered to that particular individual. Often it takes a combination of procedures to achieve success. A logical step-wise approach much be taken when a patient seeks surgery, and it is a requisite that the patient find a surgeon who understands both the pathophysiology of sleep apnea and the anatomy of the upper respiratory tract to ensure the best chance of success.