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A Real-World Study of Polynucleotides HPT for Treating Periorbital Hyperpigmentation
Raquel Amado1, Yusra Al-Mukhtar2, Eliana Lanza3
1Skin and Medical Cosmetics, West Malling, UK.
Introduction And Purpose:
Anatomic factors and age‑related changes in the midface, along with sun exposure, prolonged television viewing, anemia, and hormonal derangements, contribute to the development of periorbital hyperpigmentation, also known as dark circles. Intradermally injected PN HPT (Polynucleotides High Purification Technology) from trout gonads has an immediate volume-enhancing effect and a longer-term indirect restructuring action on dermal and subdermal tissues.
Methods:
Open-label multinational observational cohort of 61 real-life multinational subjects of both genders and unskewed age distribution (mean 41.5 ± 10.5 years, range 20 to 67), with subjectively disturbing dark circles across all Huang subtypes. PN HPT hydrogel (7.5 mg/mL) in phosphate buffer was administered with needle or cannula at baseline (T0), after two to three weeks (second injection, T1), and two to three weeks after T1 (third injection, T2); usually 1 mL on the right periorbicular area and 1 mL on the left (lower doses allowed at the specialist's discretion). Post-treatment follow-up visits: Snapshot photographs were taken at 1 month (T3) and three months after the final T2 injection (T4) and digitally analyzed for color, pigmentation, and outcomes compared with T0 (primary endpoint). Every participating specialist and every treated subject also assessed hyperpigmentation and skin quality categories with GAIS-like scoring scales.
Results:
Regarding the primary endpoint, the overall picture showed a generalized, highly significant shift toward less severe periorbital hyperpigmentation (p <0.001), especially among needle-treated subjects with the structural subtype. The progressive improvements at T3 and T4 in the evaluated perceptual skin quality categories were also remarkable for both participating specialists and treated subjects.
Conclusion:
The double-edged rationale of low-concentration PN HPT - immediate correction of hollows and tissue loss, and longer-term restructuring of periorbital connective tissues - may be a sound option for improving the appearance of dark circles and the lives of subjects with this aesthetic nuisance.

