title: The effect of antiadhesion agent on peri-implant capsular formation in rabbits.
abstract: OBJECTIVE
  Capsular contracture is the most troublesome complication after aesthetic breast surgery. Capsule formation can be seen as a normal foreign body reaction caused by implant insertion into the body. Pathological capsular contracture can lead to severe symptoms including pain, tenderness, and breast distortion. Hypertrophic scar hypothesis, one of the prevailing theories, implicates hematoma, granuloma, or other factors in capsular contractures. There are also animal studies that measure adhesion-induced capsule using fibrin glue. The authors performed the experiment to evaluate reductions in capsule formation using antiadhesion agent (AAA).
  
  
  METHODS
  Twelve smooth-surfaced cohesive-gel implants were implanted in 12 New Zealand white rabbits weighing 1.8 to 2.6 kg. These 5 × 5 × 1 cm sized miniature implants were designed in accordance with products currently used for breast augmentation. After skin incision, the exposed latissimus dorsi muscle was elevated, and a submuscular pocket was made. The rabbits were divided into 2 groups. In the experimental group (n = 6), the implant and 2 mL of AAA (Guardix) were inserted into the pocket under the muscle. In the control group (n = 6), implants and 2 mL of saline were inserted into the pocket. During the 2-month follow-up period, the rabbits were imaged monthly by 3-dimensional computed tomography to study capsule formation changes. After 2 months, the animals were euthanized, and implants with peri-implant capsule were excised. We evaluated capsule thickness, collagen pattern, and myofibroblast ratio on ventral, lateral, and dorsal aspects in a blinded fashion.
  
  
  RESULTS
  No significant differences in capsule thickness or capsular contractures were observed on gross examination or 3-dimensional computed tomography. On histological evaluation, capsule was thinner on all aspects (ventral, P = 0.027; lateral, P = 0.027; dorsal, P = 0.028; all P < 0.05), the pattern of collagen had more parallel alignment at low density, and the myofibroblast ratio was lower (ventral, P = 0.009; lateral, P = 0.002; dorsal, P = 0.004; all P < 0.05) in the experimental group than in control group.
  
  
  CONCLUSIONS
  We suggest that AAA can be helpful in reducing capsule formation. Later, clinical trials are needed to evaluate this finding.
authors.affiliation: From the *Department of Plastic and Reconstructive Surgery, Chung-Ang University Hospital; †Department of Plastic and Reconstructive Surgery, Samsung Medical Center; and ‡Department of Pathology, Chung-Ang University Hospital, Seoul, Korea.
authors.forename: Kee Cheol
authors.initials: KC
authors.lastname: Shin
authors.forename: Kun Il
authors.initials: KI
authors.lastname: Chung
authors.forename: Bo Young
authors.initials: BY
authors.lastname: Park
authors.forename: Han Koo
authors.initials: HK
authors.lastname: Kim
authors.forename: Woo Seob
authors.initials: WS
authors.lastname: Kim
authors.forename: Tae Hui
authors.initials: TH
authors.lastname: Bae
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Kim
mesh_terms: D000818:Animals; D019928:Breast Implantation / Q000009:adverse effects*; D018427:Breast Implants / Q000009:adverse effects*; D002266:Carboxymethylcellulose Sodium / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004338:Drug Combinations; D005500:Follow-Up Studies; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D057910:Implant Capsular Contracture / Q000209:etiology / Q000517:prevention & control*; D011474:Prosthesis Design; D011817:Rabbits; D000267:Tissue Adhesions / Q000188:drug therapy*; D014945:Wound Healing / Q000502:physiology
chemical_list: D004338:Drug Combinations; C000588779:guardix; D006820:Hyaluronic Acid; D002266:Carboxymethylcellulose Sodium