Objective: To clarify whether it is necessary to reconstruct bone defects at the anterior skull base.
Methods: A long-term follow-up study of 50 patients with anterior skull-base defects in which the dura was reconstructed without bone grafts was conducted. CT and MRI examinations were taken periodically after surgery.
Results: The ordinates of the bone defects averaged 3.5 cm (range, 2 - 6 cm), and the abscissas averaged 2.8 cm (range, 2 - 5 cm). The abscissas of the bone defects measured 2 - 3 cm in 38 patients, 3 - 4 cm in 10 patients, and 4 - 5 cm in 2 patients. The follow-up ranged from 3 months to 5 years (average, 2 years).
Conclusions: At normal intracranial pressure, if the dura mater is repaired properly at the skull-base defects and reinforced with a pedicled pericranial flap, encephalomeningocele and cerebrospinal fluid (CSF) leakage can be prevented. It may not be necessary to make free bone grafts when the size of the cranial base bone defect is smaller than 4 cm.