Long-term Results of Stellate Ganglion Block in Patients with Olfactory Dysfunction

Background: Olfactory dysfunction, including anosmia and hyposmia is difficult to treat. Although the mechanism is not well known, stellate ganglion block (SGB) is used to treat olfactory dysfunction. There are no prior studies on the long-term effects of SGB on olfactory dysfunction. The purpose of this study was to evaluate the continuity of therapeutic effects and patient satisfaction with SGB treatment. Methods: This was a follow-up study carried out via a telephonic survey. The olfactory function of the patient was evaluated using a visual analog scale (VAS). We checked VAS three times: VAS-I (pre-treatment VAS), VAS-A (post-treatment VAS), and VAS-C (VAS at follow up telephone survey). We divided the subjects into 2 groups according to their responsiveness to SGB: the responsive (R group) and the unresponsive groups (UR group). Patient satisfaction was evaluated using a Likert scale. Results: Out of the 40 subjects, 37 responded to the telephone survey. In the UR group, there was difference in the olfactory function. However, in the R group, there were significant VAS differences; VAS-I was 9.6 +/- 0.7, VAS-A was 5.1 +/- 4.2, and VAS-C was 2.7 +/- 2.7 (P < 0.05). On the Likert scale, patient satisfaction was as follows: grade 1, 17 patients (45.9%); grade 2, 6 patients (16.2%); grade 3, 6 patients (16.2%); and grade 4, 8 patients (21.6%). Conclusions: SGB is a safe, long-lasting, and effective therapeutic modality for olfactory dysfunction treatment.