Does cranioplasty following decompressive craniectomy improve consciousness?

BACKGROUND: Cranioplasty (CP) following decompressive craniectomy (DC) is traditionally viewed as a cosmetic procedure having no effect on neurological function in most cases after severe brain injury. However, anecdotal cases of improvement in conscious level after CP have been observed in clinical practice. AIM: To investigate whether CP is associated with consistent change in level of consciousness. METHOD: Records of patients undergoing CP from January 2007 to January 2009 were retrospectively reviewed. Four measurements were taken between DC and CP and four following CP. Each measurement included total Glasgow Coma Scale (GCS), individual GCS components, pupil size and limb power. Pre- and post-CP values were compared. Data were collected and analysed using Microsoft Excel and SPSS. RESULTS: Twenty-three patients, 16 males, mean age 37 years (range 16-64), were studied. There was a significant improvement in GCS over time (p<0.01). To test the specific impact of CP, immediate pre- and post-CP GCS values were compared, assuming time-based improvement over this interval is minimal and improvement is attributable to CP. No significant change in immediate pre- and post-CP GCS was found. CONCLUSIONS FOR DISCUSSION: Improvement in consciousness attributable to CP has significant implications for clinical practice. This study found no evidence that CP has an effect on GCS in addition to expected time-based recovery. The results were limited by the sensitivity of the Glasgow Coma Scale.