The T2-weighted image (Figure 1) revealed bilateral high-signal-intensity lesions in the region of Meckel caves, extending in a contiguous fashion into both petrous apices. These lesions followed the signal characteristics of cerebrospinal fluid on all imaging sequences and did not show any abnormal enhancement with gadolinium administration (Figure 2). The computed tomographic scan demonstrated smooth extrinsic scalloping of the left petrous apex but no osseous erosion or destruction (Figure 3). No expansion or scalloping was observed in the right petrous apex. A diagnosis of bilateral PACs was made.