Cortical Craniectomy - Effective in the Treatment of the Exposed Skull

Exposed cranial bone can present a considerable challenge to the reconstructive surgeon.  Removal of the outer cortex of exposed skull bone has proven effective in complex situations where traditional reconstruction efforts were not considered ideal.

METHODS:  Three patients with exposed skull after treatment for invasive skin cancers were treated with removal of the cortical bone in the areas of exposure. All three patients had desiccated exposed bone at the sites and thin, atrophic skin surrounding the defects that negated local skin flap reconstruction. The patients were elderly, aged 72 to 92, had numerous medical problems and were not judged to be fair candidates for more complex reconstructions. The two smaller defects measured 3 x 4 cm and 4 x 4 cm and were at sites of basal cell carcinoma treatment in men with atrophic scalps scarred from previous surgeries. The largest defect was in a 92 year woman and measured 8 by 12 cm.  The defect had been present for more than three years after radiation to the scalp for recurrent squamous cell carcinoma.  Intermittent osteomyelitis of the skull necessitated periodic antibiotics.  She wore a hair piece over the defect and a malodorous exudate was a constant companion.  Reconstruction had been denied by numerous surgeons. 

A grinding burr and drill were used to remove the outer cortex of the exposed skull.  The uncovered medullary bone layer was treated conservatively with daily antibiotic ointment and a light dressing application. Dressing changes were performed by family members. Skin grafting was not utilized.

RESULTS:  The exposed medullary bone healed in all three patients with this conservative approach.  The surgery was performed as an outpatient in all three patients.  Conscious sedation was utilized in two patients and one patient required only local anesthesia.  The cortex removal with the drill burr was completed in less than one hour, was painless and minimal bleeding was encountered. Granulation tissue developed over the medullary bone within a four week period.  Epithelialization was complete in the two smaller defects by the seventh week. The largest (8 x 12 cm) defect was judged to be healed after four months.  However, a few small areas within the defect had not fully epithelialized.  Clinically, the woman improved rapidly after removal of the infectious process.   No osteomyelitis or infectious complications occurred after the cortical craniectomy in these patients. 

DISCUSSION: Exposed skull bone is prone to desiccation and subsequent osteomyelitis if left uncovered.  Complex reconstructions may not be appropriate in many situations.  Atrophic scalp skin, radiation injury after skin cancer treatment and scarring from multiple surgeries often limit reconstructive options. Cortical craniectomy of the exposed skull bone is a simple, local technique that allows for secondary healing of the skull.  While skin grafting to defects will shorten healing time once granulation tissue covers the medullary bone, skin grafting was not utilized in these three patients.