To characterise the appearance of lesions of the tongue base and soft palate induced by bipolar radiofrequency volumetric tissue reduction, using magnetic resonance imaging up to six weeks post-procedure.

Five men with sleep-disordered breathing were treated with one session of bipolar radiofrequency volumetric tissue reduction to a number of sites, including the tongue base and soft palate. Magnetic resonance imaging was performed pre-operatively and one week and six weeks after surgery.

Lesions were visible from day one. T1 (spine lattice relaxation Time)-weighted images demonstrated areas of central hyperintensity, reflecting haemorrhagic, coagulative necrosis, surrounded by hypointensity, representing oedema; corresponding short tau inversion recovery (STIR) sequences showed central hypointensity with surrounding high signal. The lesions expanded up to day three and then gradually diminished, but were still evident at week six on short tau inversion recovery images.

The characterisation of lesions induced by bipolar radiofrequency volumetric tissue reduction enables us to elucidate the pathophysiology of this procedure, to optimise treatment benefits and clinical outcomes, and to explain patient symptoms.

In the last decade tonsillotomy has come into vogue again, whereas the number of tonsillectomies is decreasing rapidly. Currently, most tonsils are reduced by utilise electrosurgery, radiofrequency or carbon dioxide laser. However, it is not clear whether radiofrequency tonsillotomy is as effective as laser or other surgical techniques in respect of post-operative pain and haemorrhage.

A prospective, randomised, double-blinded, controlled, clinical study was conducted in the otorhinolaryngology department of Ludwig Maximilians University, Munich, Germany. Twenty-six children with tonsillar hypertrophy were included. Exclusion criteria were: history of peritonsillar abscess, previous tonsil surgery, tonsillitis within two weeks, pain before surgery, psychiatric illness, asymmetrical tonsils, chronic analgesic usage, bleeding disorders and other surgical procedures during the same operation. Tonsillotomy was performed on one side with radiofrequency and on the other side with a carbon dioxide laser. All procedures were performed by a single surgeon, under general anaesthesia. A visual analogue scale was used to measure patients' pain on each side, administered by a ‘blinded’ nurse on the three post-operative mornings and evenings, within the hospital.

There was no difference in post-operative pain scores or haemorrhage, comparing laser versus radiofrequency tonsillotomy. Patient's overall reported pain was very modest compared with post-tonsillectomy pain. No haemorrhage or other adverse effects were observed.

To determine the incidence of complications following temperature-controlled radiofrequency treatment of the soft palate, uvula and tongue base.

Retrospective study.

We included all patients who had received temperature-controlled radiofrequency treatment of the soft palate, uvula and tongue base, for sleep-disordered breathing, over a four-year period in a tertiary hospital. Patients' medical records were systematically reviewed for radiofrequency treatment parameters and complications.

Complication rates.

Seventy-six patients had been treated, with a total of 127 treatment sessions and 544 lesions to the palate, uvula and tongue base. The incidences of minor and moderate complications were, respectively, 2.6 per cent (14/544 lesions) and 0.4 per cent (2/544 treatment lesions), being 3.0 per cent (16/544 lesions) overall. Subdividing by anatomical region, the incidences of minor and moderate complications following palatal and uvula radiofrequency treatment were, respectively, 3.1 per cent (14/446 lesions) and 0 per cent, and those following tongue base treatment were, respectively, 0 per cent and 2.0 per cent (2/98 lesions). The incidence of minor complications following soft palate and uvula treatment, per treatment session, was 10.9 per cent. The incidence of moderate complications following tongue base treatment, per treatment session, was 4.6 per cent. There were no major complications in our study population.

In this study, the incidence of complications of temperature-controlled radiofrequency treatment of the palate, uvula and tongue base was low. Temperature-controlled radiofrequency is a safe treatment modality for patients with sleep-disordered breathing and can be performed as a day case procedure. We recommend day admission for patients undergoing radiofrequency of the tongue base, in view of the potential for severe complications and airway compromise.