The pillar implant is the latest in a series of measures attempting to address the challenge of sleep-disordered breathing, whether simple snoring or obstructive sleep apnoea (OSA). Logically, this technique should work. Implanting reinforcing plastic rods into a flapping palate should stop the vibratory sound of palatal flutter, a major component of the noise of snoring.
Traditional approaches rely on radical surgery or thermal trauma to produce fibrosis, scarring and palatal stiffening.
If proven effective, this operation offers the promise of equivalent benefit, with less post-operative discomfort, from a single local anaesthetic procedure.
|Traditional techniques rely on thermal trauma (left); pillar implants (overlain, right) cause less discomfort|
Snoring and OSA
Depth of sleep, sedation and alcohol all induce the loss of muscle tone causing snoring.
The ideal management is lifestyle change. Shift work, a hypoplastic mandible, big tonsils with a floppy palate and a partner who is a light sleeper are factors the patient cannot easily correct. Smoking, raised BMI and excessive alcohol intake can be addressed more easily.
Before referring the patient with sleep-disordered breathing, differentiate simple snoring from true OSA. Cessation of respiration, O2 desaturation and daytime somnolence are typical of the latter. OSA requires formal sleep studies to be carried out. Lifestyle issues and continuous positive airway pressure (CPAP) ventilation are the 'gold standard' for management. Surgery and general anaesthesia are not always advisable.
I have been using laser therapy on highly selected snorers for 15 years. As a member of the speciality advisory panel, I advised NICE in preparation of their guidance IP240 and 241, Soft Palate Implants for Simple Snoring and for Obstructive Sleep Apnoea, respectively.
Working with NICE has taught me that, however idiosyncratic their recommendations sometimes seem, their literature evaluation team is superb at critical appraisal of what can be very limited research data.
As with all surgery of snoring, there are only small-scale, non-randomised studies available for the pillar technique, with short follow up, and uncertainty and inconsistency surrounding outcome criteria.
NICE concluded that soft palatal implants should not be used in the treatment of OSA and only in snorers as part of a formal research study. Although slightly obscure, it is worth recalling that 'Lack of evidence of effect' is not evidence of lack of effect.
Many procedures that are the mainstay of surgical practice have never been subjected to randomised controlled trials.
The pillar system was introduced in 2003 in an effort to reduce palatal flutter. Local anaesthesia, a hollow introducer needle for application and a patient lacking the gag reflex are required. At a single 30 minute sitting, three small rods are injected, in parallel and longitudinally, into the soft palate, entering at its junction with the bony hard palate, to lie in the muscular layer.
The implants are 18mm long and made of inert braided plastic to avoid tissue reaction. Endoscopic examination ensures that the distal end has not penetrated into the nasopharynx.
All studies agree there is very little discomfort, lasting for a day or two at most, in marked contrast to current snoring surgery.
The peer-reviewed scientific literature reveals reported results on only just over 200 patients with 'simple snoring' and fewer with OSA. So far the use of this technology is limited outside of the US. Several private centres offer the technique. The few who specify costs suggest around £900-£1,000.
The US FDA may have approved the technique, but we will not yet see it in NHS practice. The most common outcome measure for snoring benefit, in two case series and one randomised controlled trial, is the bed partner's assessment, on a visual analogue scale (0-10). Studies suggest initial values around 7 reduce to 4 at one year. Around 75-90 per cent of snorers would recommend this to others.
However, four case series of use in mild-to-moderate OSA, showed that reductions in frequency of apnoeas, daytime somnolence and in 02 saturation were modest or insignificant. A US study suggests that multi-level surgery to the nose and tongue base, combined with palatal implants, may benefit OSA.
In September 2007, the manufacturers began a study combining CPAP with pillar implants in 100 patients with OSA, again seeking a cumulative benefit.
This is a novel technique, which can only be effective in abolishing snoring purely due to palatal flutter (a rare event). It is simply performed, requires only local anaesthesia and is less painful than rival techniques.
However, it requires retention of a foreign body in a structure whose mobility is the very problem and there are limited data on long-term follow up and extrusion rates.
Concerns centre more on efficacy than safety. The supportive evidence did not stand up to NICE scrutiny but then what kind of snoring surgery would?
- Mr Flood is a consultant ENT surgeon in Middlesbrough.