Day-case holmium laser enucleation of the prostate for gland volumes of < 60 mL: early experience.

BACKGROUND

Unilateral facial paralysis (UFP) results in profound functional and psychosocial impairment. The six-month threshold is a critical clinical crossroads where spontaneous recovery becomes unlikely, yet mimetic muscles remain receptive to reinnervation. This systematic review evaluates the efficacy of facial reanimation surgery in patients with persistent UFP of diverse etiologies lasting at least six months.

METHODS

Following PRISMA guidelines, we searched PubMed, Cochrane Library, ScienceDirect, and Web of Science for studies published between 2015 and 2025. Six studies involving 133 patients met the inclusion criteria. Quality was appraised using the Newcastle Ottawa Scale (NOS). Due to substantial heterogeneity in surgical techniques and outcome measures, a qualitative narrative synthesis was performed.

RESULTS

The five retrospective cohort studies and one prospective study included in this review suggest that surgical intervention beyond the six month threshold is associated with favorable functional recovery. Nerve transfer procedures frequently linked to improved House Brackmann and Sunnybrook scores. Free gracilis muscle transfer demonstrated positive trends in smile excursion, particularly with the U-shaped technique, while direct muscle neurotization showed limited benefit. Despite a low risk of bias on the NOS, the primarily retrospective nature of these studies warrants a cautious interpretation of the observed clinical trends.

CONCLUSIONS

Surgical reanimation for UFP beyond six months demonstrates promising clinical trends. However, this review does not establish the definitive superiority of any single surgical technique. Selection requires a highly individualized approach, and standardized reporting remains essential for future research to refine technique selection and optimize patient outcomes.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at https://doi.org/10.1007/s12663-026-03086-6.