Beyond the needle: how clinician expertise affects outcomes in the treatment of hemifacial spasm.

Background: Hemifacial spasm (HFS) is characterized by abnormal contraction of the muscles innervated by the seventh cranial nerve. It is usually benign and diagnosed clinically. The effectiveness of botulinum toxin (BoNT) for its treatment has been well demonstrated. However, adverse events (AEs) resulting from its administration remain a concern, and some patients express reluctance to be treated by resident physicians, even when under expert supervision. Objective: To determine the association between the level of expertise of the neurology professional and the presence of AEs following BoNT administration in patients with HFS. Methods: A cross-sectional descriptive study with an analytical phase conducted at Hospital Occidente de Kennedy (Bogotá, Colombia). Out of 88 medical records reviewed, 73 met all inclusion criteria. Data analysis was performed using SPSS software version 22. Results: A predominance of female patients was observed, accounting for 74 % of the study population. The mean age of symptom onset was 54.5 ± 12.7 years, with a median symptom duration of 9 years. In most cases, the left side was affected (53.4 %). The average number of botulinum toxin applications per patient was 2.6 during the study period. Adverse events occurred in 12.6 % of cases, primarily mild facial paresis (7.9 %), hematoma (2.6 %), and eyelid ptosis (2.1 %). Conclusions: The results did not show a statistically significant association between the level of expertise and the occurrence of adverse events. The frequency of observed adverse events was similar between the groups. This suggests that the occurrence of adverse events following BoNT administration was comparable regardless of whether the procedure was performed by a neurologist or a resident under supervision.