Does difference in the storage method of bone flaps after decompressive craniectomy affect the incidence of surgical site infection after cranioplasty? Comparison between subcutaneous pocket and cryopreservation.

BACKGROUND

After decompressive craniectomy for brain swelling, bone flaps need to be stored in a sterile fashion until cranioplasty. Temporary placement in a subcutaneous pocket (SP) and cryopreservation (CP) are the two commonly used methods for preserving bone flaps. Surgical site infection (SSI) is a serious complication of cranioplasty, and the storage method associated with a lower SSI incidence is favored. It is unclear, however, whether one storage method is superior to the other in terms of SSI prevention.

METHODS

During a 9-year period, 70 patients underwent decompressive craniectomy and subsequent cranioplasty. Bone flaps from 39 patients were stored using SP and those from the other 31 were stored using CP. Demographic data and SSI incidence was compared.

RESULTS

There were no significant demographic differences between the groups. SSI occurred in seven patients: 2 (5.1%) in the SP group and 5 (16.1%) in the CP group. The difference was not statistically significant (p = 0.23). When each group was further divided into two categories based on etiology (traumatic brain injury [TBI] versus non-TBI), CP showed a significantly higher SSI incidence compared with SP (28.6% versus 0%, p = 0.02) in the TBI category. However, the difference in incidence was not significant in the non-TBI category.

CONCLUSIONS

SP and CP may be equally efficacious for storage of bone flaps of non-TBI etiology; however, SP may be the storage method of choice for TBI. It remains to be verified in a prospective fashion whether SP is truly the better method of storing bone flaps in TBI.