Intraoral electrical muscle stimulation in the treatment of snoring.

The tone of the intraoral und pharyngeal muscles of the upper airway is of particular importance for the development of snoring. By increasing the tone with electrical stimulation, a reduction in snoring may be achieved. The aim of the study was to record the effects of intraoral muscle stimulation during the day on snoring at night. The prospective bi-centric study included 16 patients with snoring and mild obstructive sleep apnoea (Apnoea Hypopnoea Index [AHI] < 15, BMI < 32). After initial polygraphy, snoring was monitored over 2 weeks (baseline) using a visual analogue scale (VAS; 0-10). This was followed by a 6-week treatment phase (2â€¯× 20 min daily) with an intraoral electrical stimulation device. During and up to 2 weeks after therapy, snoring intensity in addition to use and potential side effects were documented on a daily basis. Three patients discontinued therapy because of technical problems. The 13 remaining patients (11 male/2 female, BMI 26.9 ± 3.2, AHI 9.3 ± 4.6) underwent per-protocol analysis. The mean snoring score was reduced from 5.6 ± 1.1 (baseline) to 3.2 ± 2.7 (after therapy) and remained stable until 2 weeks after treatment (3.3 ± 2.4). In 7 patients (53.9%) the score was reduced by more than 50%. Patients with an AHI < 10 responded better to therapy. No unexpected events occurred. In the present pilot study, the first signs of the effectiveness of intraoral muscle stimulation in snoring patients were shown. In addition to a technical improvement of the stimulator, carrying out controlled trials and assessing potential influencing factors on the success of therapy are necessary.

Cerebral mechanisms of experimental hyperalgesia in fibromyalgia.

The present study examined the hyperresponsiveness of the central nervous system in patients with fibromyalgia syndrome (FMS) related to mechanical hyperalgesia. The goals were to differentiate between increased pain ratings and hyperalgesia related either to peripheral or to central sensitization and to correlate with cerebral activation pattern. Seventeen patients and 17 healthy controls were examined, placing an experimental incision in the right volar forearm and causing tonic pain. Experimental pain, primary and secondary hyperalgesia were assessed during the time course of the experimental pain, and the changes in hyperalgesia were correlated to brain activation (functional magnetic resonance imaging). Patients with FMS experienced the experimental pain during the time course as more painful than healthy controls (F(score) = 3.93, p(score) = 0.008). While they did not present a different course of primary hyperalgesia (F(score) = 1.01, p(score) = 0.40), they did show greater secondary hyperalgesia (F(score) = 5.45, p(score) = 0.004). In patients with FMS, the cerebral pattern corresponding to secondary hyperalgesia was altered. The activity in the dorsolateral prefrontal cortex was inversely correlated with secondary hyperalgesia in healthy controls (R = -0.34 p = 0.005); in patients, this correlation was disrupted (R = 0.19 p = 0.12). These findings point to an alteration of pain transmission at the central level in FMS (e.g., loss of inhibition) and might be related to changes in cerebral-midbrain-spinal mechanisms of pain inhibition.