Radiofrequency ablation in snoring surgery: local tissue effects and safety measures

Abstract

Radiofrequency ablation is now widely used in the treatment of patients with snoring and obstructive sleep apnoea. It is well suited to the multilevel approach typically required in snoring surgery and can be used interstitially or in cutting mode. However, no research has been performed to analyse the collateral local tissue damage or size of lesions induced by radiofrequency application. This is the first study of the histological effects of interstitial radiofrequency. We studied the size of tissue lesions generated at differing power settings with and without local anaesthetic application in human tonsils and chicken breast tissue. The size of the lesion was independent of power setting and local anaesthetic infiltration. The typical effect was an oval-shaped lesion centred on the active electrode, 6-7 mm in width and 7-8 mm in length. This was confirmed histopathologically, with smaller lesions generated in the submucosa (2 × 3 mm) but with no collateral tissue damage beyond this distinct zone of injury. To avoid complications, we recommend placing contiguous radiofrequency applications at least 8 mm apart. Post-nasal space packing raises and tautens the soft palate. The use of local anaesthetic increases interstitial volume, thereby reducing the risk of incorrect probe placement and resultant ulceration or fistulation.

When continuous positive airway pressure (CPAP) fails

“…A full assessment of co-morbidities and specifically body mass index is required, as the latter has been shown to correlate with surgical outcomes. In fact, surgery is often not recommended unless the BMI is less than 35 kg/m 2 (40,41). It is important to specifically query patients regarding any rhinological symptoms.…”

Electrosurgery Turbinate Reduction Revisited: Can Comparable Volumetric Heating be Achieved Without Feedback Control?

“…Chicken breast has a visible coagulation zone and uniform tissue, resulting in more predictable behavior that would aid in accurate measurements of coagulum [19]. Though both egg white and chicken breast phantoms are well‐established, there are obvious differences between the models used in this study and the inferior turbinate [33–35]. One such difference is that the lesions created in the well vascularized nasal inferior turbinate are influenced by the flow of blood, which removes heat from the tissue surrounding the electrode [17].…”

Minimally Invasive Radiofrequency Surgery in Sleep-Disordered Breathing

“…The mucosa is cleaned with chlorhexidine to reduce potential infection. Two tonsillar swabs are placed posterior to the soft palate to prevent inadvertent injury to the posterior pharyngeal wall [8,23].…”

“…The relatively low incidence of complication is thought to result from the mechanism of radiofrequency. Radiofrequency causes ionic agitation and, therefore, heating of the surrounding tissues as opposed to the probe itself; this results in a predictable tissue injury pattern at a significantly lower temperature than direct electrocautery [23]. A histological study identified that the size of the lesion caused by interstitial radiofrequency is reliably an oval-shaped lesion, 6–7mm in width and 7–8mm in length [23].…”

“…No significant collateral tissue damage beyond this point was identified. Virk et al subsequently advised that to avoid complications, radiofrequency applications should be made at least 8mm apart, and using local anaesthetic increases the interstitial volume, which reduces inadvertent mucosal erosion or fistulation [23]. Additionally, the radiofrequency probe must be fully inserted to prevent mucosal injury.…”