title: Easy-to-Use Preservation and Application of Platelet-Rich Plasma in Combination Wound Therapy With a Gelatin Sheet and Freeze-Dried Platelet-Rich Plasma: A Case Report.
abstract: OBJECTIVE
  Platelet-rich plasma is blood plasma enriched with platelets and contains various growth factors. Two major issues remain to be resolved in the use of platelet-rich plasma: the short biological activity after application, and the need to prepare platelet-rich plasma at each application instance. To overcome these problems, we developed a drug delivery system using gelatin hydrogel and preserved the excess platelet-rich plasma as freeze-dried platelet-rich plasma. We then applied combination treatment with a gelatin sheet and platelet-rich plasma at the first instance and freeze-dried platelet-rich plasma at the second instance in the treatment of a nonhealing wound.
  
  
  METHODS
  A 68-year-old woman had suffered open fracture of her right tibia 2 years prior, and a split-thickness skin graft had been applied to repair the skin defect on the right tibia. She had multiple relapse of ulcers, and the present ulcer had not healed for 2 months. After debridement, 2 mL of activated platelet-rich plasma was applied to the ulcer, and the gelatin sheet was laid to impregnate with the platelet-rich plasma, after which the sheet was covered with a polyurethane film. Thirty-three days after the first platelet-rich plasma application, the freeze-dried platelet-rich plasma was reconstituted and 2 mL of the reconstituted platelet-rich plasma was applied with a gelatin sheet.
  
  
  RESULTS
  At 14 days after the freeze-dried platelet-rich plasma application, the wound was mostly epithelized, with the rest of the wound covered with granulation tissue.
  
  
  CONCLUSIONS
  These findings suggest that combination wound therapy with a gelatin sheet and freeze-dried platelet-rich plasma is a promising method for resolving issues with conventional platelet-rich plasma treatment.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Osaka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Morimoto
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Osaka, Japan.
authors.forename: Natsuko
authors.initials: N
authors.lastname: Kakudo
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Osaka, Japan.
authors.forename: Tsunekata
authors.initials: T
authors.lastname: Ogura
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Osaka, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Hara
authors.affiliation: Department of Biomaterials, Field of Tissue Engineering, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Matsui
authors.affiliation: Polymer Chemistry Division, Chemical Resources Laboratory, Tokyo Institute of Technology, Tokyo, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: Department of Biomaterials, Field of Tissue Engineering, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Osaka, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kusumoto
keywords: chronic skin ulcers; controlled release; freeze-dried; gelatin sheet; platelet-rich plasma