Introduction:
The stimulation lead cuff of the selective upper airway stimulation system (Inspire
Medical Systems, Maple Grove, USA) contains three electrodes. This results in various
configuration options (monopolar and bipolar settings). The bipolar configuration
+ – + is the default setting. However, in some cases monopolar stimulation leads to
more efficient reduction in the apnea-hypopnea index (AHI) or is better tolerated
by the patient. The aim of this study was to investigate the effects of monopolar
configurations on the clinical outcome.
Methods:
All patients who received an upper airway stimulation system since April 2014 and
had a monopolar electrode configuration at the 6-month or 12-month follow-up were
enrolled. Treatment outcome data were collected including AHI, Epworth Sleepiness
Scale (ESS) and adherence to therapy.
Results:
Out of 100 implanted patients, 11 patients (sex: 11 male; age: 66 ± 13 years; BMI:
29.4 ± 2.6 kg/m2) had monopolar stimulation settings. The baseline median AHI could be reduced from
41.1 ± 17.6/h to 12.6 ± 8.6/h after 6 months and to 9.2 ± 16.1/h after 12 months.
The median ESS decreased from 14.0 ± 6.1 to 7.0 ± 3.9 (6 months) and further to 6.0
± 5.3 (12 months). The nightly usage duration was 5.9 ± 2.0h at 6 months and 6.2 ±
2.3h at 12 months.
Conclusion:
Patients with monopolar electrode configurations for optimal tongue movement achieve
similar good clinical results compared to patients with standard bipolar configurations.
Various electrode configurations lead to improved stimulation for optimized and customized
therapy.
