This study evaluated the efficacy of ALIDYA, a Class III medical device used in needle mesotherapy, for the treatment of cellulite (gynoid lipodystrophy) in women. Thirty female volunteers aged 20-45 years with cellulite graded 1 to 4 on the Nürnberger-Müller scale received a series of six mesotherapy treatments administered weekly to the posterior thighs. The study aimed to determine whether this treatment could improve the clinical appearance of cellulite and produce measurable changes in skin structure, microcirculation, and tissue composition. Assessments were performed before treatment, one month after the first application, and three months after the first application, using expert clinical grading as well as several objective instrumental methods: standardized clinical photography with texture analysis, thermal imaging, hyperspectral imaging, three-dimensional skin surface analysis (Antera 3D), and high-frequency ultrasound. The hypothesis was that ALIDYA would reduce the severity of cellulite by improving skin surface topography, microcirculation, and the structural quality of the skin.