Investig Magn Reson Imaging.  2017 Jun;21(2):114-118. 10.13104/imri.2017.21.2.114.

Skull Base Dermoid Cyst in the Right Infratemporal Fossa Diagnosed Using the Dixon Technique: a Case Report and Review of Literature

• Kim SJ
• Baek HJ
• Ryu KH
• Choi BH
• Moon JI
• Cho SB
• Park SE
• Bae K
• Jeon KN
• Cho EB
• An HJ

• KMID: 2385610
• DOI: http://doi.org/10.13104/imri.2017.21.2.114

Abstract

Dermoid cysts are benign congenital tumors composed of keratinizing squamous epithelium and dermal derivatives. They account for less than 1% of all intracranial tumors and are rarely exhibited at the base of the skull. To the best of our knowledge, only one case report has presented computed tomography and conventional T1-weighted magnetic resonance (MR) findings that revealed an infratemporal dermoid cyst. In the present study, we report an unusual case of a dermoid cyst in the right infratemporal fossa, which was incidentally detected by MR imaging with the Dixon technique. This article also highlights the importance of meticulous radiological review and the usefulness of the Dixon technique in everyday clinical practice.

Keyword

Dermoid cyst; Skull base; Infratemporal fossa; Magnetic resonance imaging; Dixon technique

MeSH Terms

Dermoid Cyst*
Epithelium
Magnetic Resonance Imaging
Skull Base*
Skull*

Figure

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  Fig. 1 A 24-year-old woman presented with a complaint of recurrent seizures over the past 10 years. On T1-weighted images (a-d), a well-circumscribed, strongly hyperintense mass with a thin isointense capsule was visible in the right infratemporal fossa. Several small isointense intracystic nodules, visible in the inferior portion of the lesion (arrowheads, b and c), were considered to be an indicator of non-fatty components. The ipsilateral trigeminal nerve in the foramen ovale was clearly delineated, with a mild posterolateral displacement (arrows, a and d). On images acquired using the Dixon technique, the lesion exhibited a bright signal intensity on in-phase, T2-weighted images (e); however, on water-only T2-weighted images, the lesion exhibited uniform hypointensity due to robust fat suppression (f). On fat-suppressed fluid attenuation inversion recovery images (g), the lesion exhibited a homogenous hypointensity as well. The lesion did not exhibit definite enhancement in the internal portion or at the periphery (h).

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