Tongue base surgery

This section includes discussion of some of the biggest developments in sleep surgery. It is recommended that you read the entire section sequentially, but if you wish to click on any individual topic, please feel free to do so.

q Introduction

q Theory behind tongue base advancement

q Geniotubercle advancement

q Hyoid advancement

q Bimaxillary advancement

q Theory behind tongue base resection (partial glossectomy)

q Laser midline glossectomy

q Transcervical tongue base resection with hyoepiglottoplasty

q RFVR (Somnoplasty™)

Introduction

The development of surgical procedures that address the tongue base has revolutionized the treatment of OSAS. These techniques allow for cure rates of 90% or more, even for the most severe apneics.

There are two ways to treat the tongue base in OSA: to either pull it forward (tongue base advancement) or to reduce its size (partial glossectomy). There are roles for both of these approaches, and they will be discussed below. The decision as to which procedure(s) should be offered to any given patient is determined by careful examination of the patient’s airway, with particular attention to the size, shape, and relationship of the jaws, size and position of the tongue, position of the hyoid, and expectations of the patient. Additional information can be obtained from X-ray evaluation of the facial bones and neck.

In general, if a patient demonstrates deficiencies in the size or position of the jaws, consideration will be given to tongue base advancement, as the major problem might be that the tongue is suspended too far posteriorly in the airway by a mandible that is too small. If, on the other hand, the jaw structure is normal, the tongue itself is probably too big. Such patients should benefit most from tongue base resection.

Theory behind tongue base advancement

The position of the tongue is largely determined by the position of two bones: the lower jaw (or mandible) and the hyoid bone. Tongue base advancement surgery involves moving the tongue base forward by working with these bones.

The tongue attaches along the whole inner surface of the mandible, particularly at a part of the bone called the geniotubercle. The geniotubercle is a small bump on the inner surface of the mandible in the midline directly behind the chin. The genioglossus muscle, the main muscle responsible for sticking the tongue out of the mouth, is suspended from the geniotubercle. The hyoid bone, the uppermost bone in the throat below the mandible, is a horseshoe-shaped bone that also helps hold the tongue in position.

Most of the published data on tongue base advancement surgery has come from the surgical team from Stanford University, and it is their protocol that is most widely accepted. Their protocol involves two phases of surgery. The first includes repositioning the hyoid bone and its attached muscles (hyoid advancement) and a repositioning of the geniotubercle and attached genioglossus muscle (geniotubercle advancement). These are often performed together, in conjunction with a UPPP or UPF. The cure rate with this phase I surgery is approximately 60%.

If the OSAS is not cured in phase I, phase II surgery is offered. This consists of a bimaxillary advancement, which involves lengthening the upper and lower jaws, to further advance the tongue forward. This surgery also enlarges the mouth so that the tongue has more room, and it advances the palate forward. Very infrequently is phase II surgery offered to patients who have not undergone phase I surgery. The cure rate for phase II surgery when preceded by phase I surgery is approximately 95%.

Geniotubercle advancement

This phase I surgical procedure involves a forward repositioning of the part of the mandible called the geniotubercle, which is the point of attachment of the genioglossus muscle of the tongue. A small hole is made in the front of the jaw through an incision made on the inside of the lower lip. The genioglossus muscle is pulled through this hole and is reattached to the outer portion of the mandible. The tongue is therefore put on stretch and is less floppy during sleep.

The amount of forward pull is limited by the thickness of the mandible, which is approximately 10-14 mm. It does not result in movement of the jaw line or teeth and does not change alignment of the teeth.

Hyoid advancement

The other phase I tongue base procedure is the hyoid advancement. The hyoid bone is important in determining tongue position, and the anterior advancement of the hyoid bone can enlarge the airway at the tongue base level. This relatively simple procedure involves a small neck incision suturing the hyoid to the upper border of the thyroid cartilage (“the Adam’s apple”). It can be done under local anesthesia as an outpatient, but is usually done in conjunction with geniotubercle advancement under general anesthesia.

Bimaxillary advancement

Patients who are not cured by phase I surgery often have deficiencies in the size and position of the jaws that require a more aggressive approach to pull the tongue forward. These patients are offered phase II surgery, or bimaxillary advancement.

This involves the precise cutting of the bones of the upper and lower jaws and lengthening them approximately one centimeter. In doing so, the tongue and the palate are pulled forward and the airway is enlarged. The surgery also enlarges the mouth to make additional room for the tongue. The bite is kept unchanged from beforehand, as both jaws are advanced together. The surgery is performed through incisions made inside the mouth.

As mentioned previously, this surgery usually follows phase I surgery that has not resulted in a cure in patients with jaw deficiencies. If their jaws are normal on physical exam and X-ray examination, they may be offered a tongue base resection.

Regardless which approach is used, all patients with significant OSAS who undergo surgery should therefore be informed that though they have an excellent chance of being cured, that cure might not come after just one surgery. Additional work will be needed if a subsequent sleep study shows insufficient response to phase I surgery.

Theory behind tongue base resection (partial glossectomy)

As previously reported, one way of dealing with an enlarged or posteriorly positioned tongue base is to pull it forward (tongue base advancement). The other approach to dealing with the base of tongue is to make it smaller. There are several ways that this can be done. Tongue tissue can be removed with a laser through the mouth or can be removed through a neck incision. The tongue can also be shrunk using the same radiofrequency energy equipment previously described for the palate. Each of these approaches will be discussed below.

Tongue base resection is generally offered to patients with tongue base obstruction who have normal facial bone structure. In other words, they are not candidates for bimaxillary advancement surgery. That determination is made on physical examination and by X-rays.

Like the tongue base advancement procedures (especially phase II surgery), tongue base resection surgery is not offered in many centers in the United States, but is highly successful when performed as part of a comprehensive treatment plan for this potentially dangerous medical problem.

Laser midline glossectomy

This surgical procedure involves the use of a laser to remove excessive tongue tissue. It is done through the mouth under general anesthesia, and involves cutting a wedge of tissue from the mid portion of the tongue. It involves reducing the bulk of the soft tissue of the tongue and eliminating redundant tissue attached to it. This procedure requires a temporary tracheostomy and has a success rate as high as 80% in patients who usually also have undergone a UPPP.

Transcervical tongue base resection with hyoepiglottoplasty

An alternative way of removing excessive tongue tissue is to do so through a neck incision. This type of approach, like the laser midline glossectomy, is usually offered to severe sleep apneics with tongue base obstruction whose facial bone size and position are normal. Like the laser midline glossectomy, the cure rate is in the 80% range. The majority of patients who undergo this procedure also have had a UPPP or UPF. It can be offered to patients who have undergone geniotubercle advancement.

The procedure involves removing a wedge of tongue tissue through a neck incision. The cut edges are sewn together with dissolvable sutures, and the temporary tracheotomy is removed once the risk of swelling is gone. The procedure includes a variation of the hyoid advancement described earlier; the difference is that the hyoid is advanced forward and upward to the lower border of the mandible, rather than forward and down to the thyroid cartilage.

Radiofrequency volumetric reduction (RFVR) of the tongue base

The same Somnoplasty™ techniques that are currently being used to treat the palate for snoring holds promise as a potential treatment of the tongue base for OSAS. Tongue base Somnoplasty™ can be done in the office under local anesthesia, usually with minimal discomfort or morbidity. It involves the delivery of radiofrequency energy to the muscle of the tongue through specially designed needle electrodes. This energy causes the target tissue to scar and eventually contract, resulting in a reduction of tongue base volume. The procedure requires multiple one-hour sessions to be effective, each spaced three or more weeks apart.

This procedure is FDA approved for treatment of OSAS, but thus far only preliminary information has been published as to its effectiveness. Those initial data appear promising. A multi-institutional study is concluding in early 2000 that will provide more information. Dr. Huntley is one of the principle investigators who have been chosen to study this potentially revolutionary new technique.