Abstract
To classify the defects of the skull base, we present a new concept that is intuitive,
simple to use, and consistent with subsequent reconstructive procedures. The centers
of defects are determined in the anterior (I) or middle (II) skull base. The defects
are classified as localized in the defect's center (Ia, IIa) or extended horizontally
(Ib, IIb) or vertically (Ic, IIc) from the defect's center. Accompanying defects of
the orbital contents and skin are indicated by “O” and “S,” respectively. An algorithm
for selecting subsequent reconstructive procedures was based on the classification.
Using the new system, we retrospectively reclassified 90 skull base defects and examined
how the defect classifications were related to the reconstructive flaps used and postoperative
complications. All defects were reclassified with the new system without difficulty
or omission. The mean correlation rate was high (88%) between the flaps indicated
by the new classification and the flaps that had actually been used. The rate of postoperative
complications tended to be higher with Ia, Ic, and IIb defects and combined defects.
Our new classification concept can be used to classify defects and to help select
flaps used for subsequent reconstructive procedures.
Keywords
skull base - skull base defect - classification - reconstructive surgery
