1
Introduction
Snoring is a widespread symptom affecting about 50% of the adult population. Primary snoring without sleep-disordered breathing is not harmful in itself. However, because snoring often causes social embarrassment and marital disharmony, affected patients apply to their physicians for treatment.
The primary therapeutic aim of all available therapies is a reduction in the duration and intensity of snoring to a tolerable degree without harming the patient. Apart from conservative treatments that require patient compliance to be successful, various kinds of surgical procedures exist, with techniques for the soft palate being the most widespread. All these procedures intend to reduce palatal flutter, the major cause of non-apneic snoring. Uvulopalatopharyngoplasty (UPPP) and laser-assisted uvulopalatoplasty (LAUP) are well known, but are associated with significant morbidity. Furthermore, these treatments are invasive, destructive, painful, and irreversible to a certain extent. UPPP even requires general anesthesia.
Therefore both patients and physicians prefer a minimally invasive and less painful procedure as a primary option for the treatment of snoring. Since its invention in 1998, interstitial radiofrequency (RF) treatment of the soft palate has gained increasing interest among the public because it was the first minimally invasive surgical treatment bearing a low morbidity as well as a remarkable success rate. However, it is not a single-step procedure, and treating the palate excessively may still impair the various functions of the soft palate in a very few cases. Furthermore, a considerable relapse of snoring 1 to 
years after the last RF treatment has to be considered. As a result of this relapse of snoring, alternative therapies with minimal morbidity and long-term efficacy are desired. Therefore a new procedure was developed in 2001 in which woven cylindrical implants are placed within the soft palate to stiffen the soft palate and thus reduce snoring. These implants are made of polyethylene terephthalate, a material that has been used in heart valve surgery for the last decades.
In this chapter, the patient selection criteria for the insertion of palatal implants in the treatment of snoring and its success rate, as well as its morbidity, are described according to the literature and to our own experience. The procedure is described in detail. It is performed identically in snorers and in sleep apnea patients. During the last few years the delivery tool has been modified three times. It became smaller and contains more safety precautions against unwanted or incorrect implant deployment ( Fig. 31.1 ).
2
Patient Selection
The Pillar procedure consists of inserting implants into the junction of the hard and soft palates to extend the hard palate, thus reducing the vibrating parts. The nature of the procedure where there is no resection or ablation of palatal tissue makes the patient selection criteria for this operation comprehensible. Patients with the following findings at the upper pharyngeal level should not receive palatal implants as a solitary intervention: nasal obstruction for whatever reason, distance between both tonsils less than 2 cm, excessive palatal and pharyngeal mucosa, and a uvula longer than 1 cm ( Fig. 31.2 ). Patients with signs of tongue base snoring or obstruction in the clinical examination such as Friedman tongue position 3 or 4 ( Fig. 31.3 ), tongue base hypertrophy, retrognathia, and floppy epiglottis are also not suitable candidates for this procedure. Obesity with a body mass index above 32 kg/m 2 is known to impair any surgical intervention at the upper pharyngeal level and therefore is considered to be an exclusion criterion. In brief, patients without any obvious morphologic anomaly in their nose and pharynx except a sufficiently long soft palate are suitable candidates for a solitary Pillar procedure ( Fig. 31.4 ). Keep in mind that in all publications concerning the efficacy of palatal implants themselves, only those patients who fulfilled the previously mentioned inclusion criteria were treated.
The impact of nasal obstruction on snoring can be easily detected by applying a nasal decongestant and/or a nasal dilator before bedtime for a period of 7 days. If the improvement of nasal breathing during the night does not lead to a decrease of snoring, a combined versus a stepwise operation of the nose and the Pillar procedure may be discussed with the patient. Of course, an adjunct conservative treatment with a mandibular advancement device, positional therapy, and/or weight reduction is possible at any time and vice versa. It is well documented in sleep apnea patients that palatal implants can be inserted synchronously to or as a second step after other soft palate procedures like UPPP. It is also possible in the case of a recurrence of symptoms after such operations. Future studies have to show whether this is also true for primary snorers. RF of the soft palate, injection snoreplasty, and cautery-assisted palatal stiffening operations are not recommended as additional surgeries by us because the tissue necrosis they induce is likely to increase the risk of implant extrusion and infection (see Complications section later). There are no data concerning the combination with tongue base procedures (i.e. RF, laser resection of the lingual tonsil, genioglossus advancement, hyoid suspension), but obviously there is no surgical contraindication, as different anatomic sites are addressed. However, tongue base procedures are rarely used in primary snoring anyway.
If palatal implants are used as additional surgery, one will lose the minimally invasive character of the intervention in most cases. Therefore it has to be investigated whether the indication for an isolated Pillar procedure may generally be extended to patients considered less suitable up to now to offer this minimally invasive procedure as a real alternative to more aggressive operations as mentioned earlier. Furthermore, it is not yet clear whether additional methods for the assessment of the site of snoring sound generation can improve the selection process toward a better outcome. Regarding this issue, sound analysis using the SNAP system did not increase the success rate. Multichannel pressure recordings during natural sleep and videoendoscopy during wakefulness as well as under sedation are still under investigation.
So far, there are no data concerning the treatment of children with palatal implants. Because children mainly have shorter palates than adults, the size of the implants would probably not fit for most children.
3
Outline of the Procedure
The implant is a braided segment of polyester filaments intended for permanent implantation. The implant is 18 mm in length and has an outer diameter of 1.5 mm. The delivery tool (see Fig. 31.1 ) consists of a handle and 14-gauge needle with the implant preloaded. The implant is deployed by pushing the thumb switch. Three implants are placed near the midline into the soft palate near the junction of the hard and soft palates as if the hard palate was extended by the implants. The curved needle has three markings: a full insertion marking, a halfway depth marking, and a needle tip marking. Care must be taken to remove the transport lock and the plastic sleeve covering the tip of the needle before attempting insertion of the implants. Each delivery tool contains one implant. The delivery tools are not reusable and should be appropriately disposed of in a sharps container after the procedure.
The Pillar implant technique can be performed in the office under local anesthesia or as part of a combination of procedures in patients under general anesthesia in the operating room.
After mucosal disinfection with hexetidine 0.1% and topical anesthesia with lidocaine gel 2%, the total length of the soft palate is infiltrated in the midline and approximately 5 mm laterally with a total of approximately 3 mL of prilocaine 2% with epinephrine 1:200,000. Meanwhile 2 g cefazolin are administered intravenously, and antibiotic prophylaxis is continued for 5 days with cefuroxime 2 3 500 mg per day. Midazolam is used for sedation if desired by the patient.
The exact location of the insertion sites is determined by palpating the junction of the soft and hard palate and may be marked by the surgeon. The needle is inserted in the midline first while the neck is slightly extended, thus giving more space between the chest and delivery tool and making it easier to follow the angle and curvature of the soft palate. The needle is then advanced toward the free margin of the soft palate to the full insertion marking, which still has to remain visible. Care must be taken to always stay in the muscle layer ( Fig. 31.5 ). Correct positioning of the needle can be checked either by palpation or, more easily, by making the soft palate move anteriorly and posteriorly with the needle.
