Comparison of acrylic and titanium cranioplasty

There are many indications for cranioplasty with an increasing incidence partly attributable to an increase in decompressive craniectomy following trauma and stroke. The aim of this study was to compare the survival of acrylic and titanium cranioplasties used in our department.

Retrospective cohort study of 126 patients who underwent cranioplasty between 1997 and 2007. A comparison was made between those with acrylic (n = 61) and titanium (n = 65) cranioplasties. There was no significant difference in age and length of time between craniectomy and cranioplasty between the two groups. The indications for titanium cranioplasty tended to be classified as 'high risk' indications including trauma and stroke. A higher rate of pre-existing infection was noted in the acrylic group. Mean follow-up was 97.2 and 34 months for acrylic and titanium cranioplasties respectively.

Mean survival (95% confidence intervals) was 135 months (134-153) and 92 months (82-102) for acrylic and cranioplasty respectively. Out of 13 failures, only two were associated with pre-existing infection. Overall cumulative survival was better for acrylic cranioplasty although this difference did not reach statistical significance.

Although survival of acrylic cranioplasty appears to be better than titanium plates, there is no statistical significance. Acrylic has the advantage of being able to be applied at the time of surgery without any planning and does not cause artefact on future imaging. Titanium cranioplasty is strong, light-weight and inert and can be fashioned in the pre-operative setting.