Abstract
Postoperative evaluation by three-dimensional (3D) computed tomography (CT) was performed
in 15 patients who underwent anterior skull base reconstruction using two musculopericranial
flaps and a grafted bone sandwiched between the two flaps. Especially in the case
of large bone grafts (4 x 4 cm or more), the graft was positioned with the convex
side facing upward into the cranial cavity to avoid creating an intracranial dead
space. The extent of the absorption and changes in the contour of the grafted bone
were evaluated. Imaging was done at a CT level of 150 using a Proceed 3-D CT scanner
(Yokogawa Medical Co., Tokyo, Japan). Donor bone for grafting to the skull base was
harvested the cranium in 10 patients and the ilium in 5 others. Patients ranged in
age from 7 to 76 years (mean, 47); there were 10 men and 5 women. The grafted bone
ranged in size from 1 x 2 cm to 5 x 8 cm (1 x 2 cm to about 4 x 3 cm: 10 patients;
4 x 4 to about 5 x 8 cm: 5 patients).
No marked absorption of grafted bone was seen in these 15 patients, and no brain hernia
occurred. In patients with large bone grafts (4 x 4 cm to about 5 x 8 cm), a graft
that had been positioned with the convex side facing upward into cranial cavity at
the time of transplant was subsequently observed to be transformed into a downward
convex contour of normal skull base. Fostoperative infection did not occur because
of the dead space nor were there any symptom of pressure on the brain because of the
upward convexity of the grafted bone.
The present reconstructive method is not only a minimum invasive but also a safe and
reliable method for anterior skull base surgery.
