J Korean Soc Radiol.  2011 May;64(5):439-443. 10.3348/jksr.2011.64.5.439.

Petrous Apex Cephalocele: Report of Two Cases and Review of the Literature

• Jeong BS
• Lee GJ
• Shim JC
• Lee JM
• Nam MY
• Kim HK

• KMID: 2040811
• DOI: http://doi.org/10.3348/jksr.2011.64.5.439

Abstract

A petrous apex cephalocele is a rare lesion of the petrous apex. It can be discovered incidentally or can cause a suite of clinical problems, such as trigeminal neuralgia or cerebrospinal fluid leakage. Although this lesion can be misinterpreted as a pathologic lesion, the characteristic radiologic features can provide the diagnostic clue for distinguishing these two lesions and avoid unnecessary treatment. Here we present CT and MRI finding of petrous apex cephalocele in two patients with review of the literature.

MeSH Terms

Encephalocele
Humans
Magnetic Resonance Imaging
Petrous Bone
Tomography, X-Ray Computed
Trigeminal Neuralgia

Figure

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  Fig. 1 Axial temporal bone CT image (A) shows sharply marginated, multilobulating erosive lesions (arrows) at the bilateral petrous apex with a thin cortical bone outline (Right : 2.7 × 1.0 cm, Left : 1.6 × 1.0 cm). Axial T1-(B), T2-weighted (C), and FLAIR image (D) demonstrate CSF signal intensity at the bilateral petrous apex, contiguous to Meckel's cave (arrows in C). On contrast-enhanced T1-weighted images (E), thin wall enhancement is noted at the bilateral petrous apex lesions (curved arrows) and DWI (F) as well as ADC maps (G), which reveal the CSF-like content of lesions (arrows in F). A sagittal T1-weighted image (H) shows combined empty sella (arrow).

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  Fig. 2 Axial brain CT image (A) shows cystic lesions (black arrows) at the bilateral petrous apex. The DRIVE sequence (B) demonstrates bilateral petrous apex lesions more clearly, which are cystic and contiguous to Meckel's cave (arrows). ADC maps (C) also reveal the CSF-like content of the lesions. On a contrast-enhanced T1-weighted coronal image (D) shows localized meningeal enhancement at a high frontal area near the midline (arrows), but the lesions at the bilateral petrous apex (curved arrows) were not enhanced.

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