Soft tissue expansion and cranioplasty: For which indications?

The aim of this study was to better define indications for scalp tissue expansion before cranioplasty, and to describe our methodology for calculate the surface of tissue needed, by combining a preoperative analysis of both the size of the defect and the quality of skin above.

A retrospective analysis of patients who underwent expansion before cranioplasty between 2009 and 2015 was conducted. Information was collected on the etiology, size and location of the defect, and reasons of skin contracture. Data concerning expansion and cranioplasty were reviewed.

Among 47 patients who underwent operation for cranioplasty, five (10.6%) required previous scalp tissue expansion. The etiology of the bone defect was tumoral in three cases, posttraumatic in one case, and a decompressive craniectomy in one case. The mean surface of the bone defect was 69.6 ± 18.7 cm(2). The locations of the defects were fronto-temporo-parietal, frontal, temporo-frontal, on the vertex, and occipital. The cause associated with the skin contracture was an infection in four cases and a delayed cranioplasty in one case. A round-profile expander and a custom-made porous hydroxyapatite implant were used for all patients.

The accurate assessment of tissue needed before cranioplasty is as essential as the choice of the material used for bone reconstruction. After previous infected cranioplasty or delayed reconstruction of large defects, scalp tissue expansion should be proposed.