Resumen

Objectives: To compare conventional injection techniques with intramuscular nerve distribution guided injection for botulinum toxin in body contouring Introduction: Botulinum toxin is widely used in aesthetic practice. Recently, its off-label use for body contouring particularly in Asian populations has gained popularity. However, treating large muscle groups often requires higher doses, increasing cost and potential risk of antibody formation. Recent anatomical studies suggest that targeting areas of dense intramuscular neural arborization may allow more precise toxin delivery and achieve comparable outcomes with lower doses Materials / method: A split-side case series was performed in patients undergoing body contouring (superior trapezius, deltoid, tricep brachii and gastrocnemius muscles). One side was treated using conventional injection techniques, while the contralateral side received intramuscular nerve distribution–guided injections with a 30–50% dose reduction. Differences in injection mapping, dosing, and clinical outcomes were evaluated Results: The nerve-guided technique achieved comparable clinical improvement to the conventional technique by week 8. A more pronounced muscle weakening effect was observed with the conventional technique at week 4. Despite the lower dose, the nerve-guided approach provided similar overall outcomes Conclusion: Intramuscular nerve distribution guided injection may allow dose reduction while maintaining clinical efficacy, helping to optimize treatment outcomes in body contouring