title: Cryopreservation versus subcutaneous preservation of autologous bone flaps for cranioplasty: comparison of the surgical site infection and bone resorption rates.
abstract: OBJECTIVE
  Decompressive craniectomy is performed to treat malignant brain hypertension. Surgical site infection (SSI) and bone resorption are common complications following cranioplasty, and the storage method that minimizes such complication has yet to be identified.
  
  
  METHODS
  Over a 10-year period, the details of 290 decompressive craniectomy procedures performed at our trauma and stroke center were recorded. Bone flaps from 110 patients were preserved in subcutaneous pockets (SPs), and 180 were preserved via cryopreservation (CP).
  
  
  RESULTS
  SSIs occurred in 20 cases (18.2%) in the SP group and 20 cases (11.1%) in the CP group (P=0.129). After dividing each group according to the traumatic brain injury (TBI) etiologies, we found that in the SP group, the SSI rates in the TBI and non-TBI patients were 17.3% and. 20.7% (P=0.899), respectively, and in the TBI- and non-TBI CP-group patients, the SSI rates were 11.9% and. 9.7% (P=0.864), respectively. The average decrease in bone flap thicknesses were 1.14 mm in the SP group (n=34) and 1.89 mm in the CP group (n=57), and this difference was significant (P=0.039).
  
  
  CONCLUSIONS
  In this series, the SSI rates were similar in the SP and CP groups. There was no significant difference when the patients were grouped by TBI etiology. The incidence of bone flap resorption in the CP group was higher than that in the SP group. However, identifying of the method that yields superior results might depend on the individual surgeon's preference and the available equipment.
authors.affiliation: Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; Department of Neurosurgery, Tainan Municipal An-Nan Hospital, Tainan, Taiwan; Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan. Electronic address: u701018.tw@yahoo.com.tw.
authors.forename: Cheng-Hsin
authors.initials: CH
authors.lastname: Cheng
authors.affiliation: Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Han-Chung
authors.initials: HC
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Chun-Chung
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Der-Yang
authors.initials: DY
authors.lastname: Cho
authors.affiliation: Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan. Electronic address: linhunglin0405@yahoo.com.tw.
authors.forename: Hung-Lin
authors.initials: HL
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D001862:Bone Resorption / Q000453:epidemiology*; D015925:Cryopreservation / Q000706:statistics & numerical data; D056424:Decompressive Craniectomy / Q000009:adverse effects / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D012092:Replantation / Q000009:adverse effects / Q000706:statistics & numerical data*; D040521:Subcutaneous Tissue / Q000601:surgery*; D013524:Surgical Flaps / Q000706:statistics & numerical data*; D013530:Surgical Wound Infection / Q000453:epidemiology*; D014021:Tissue Preservation / Q000706:statistics & numerical data*
keywords: Autologous cranioplasty; Cryopreservation; Decompressive craniectomy; Subcutaneous pocket; Surgical site infection