CSF fistula secondary to sphenoid meningoencephalocele - Imaging Clinic - cerebrospinal fluid

Ear, Nose & Throat Journal, Dec, 2003 by Michael D'Antonio, Enrique Palacios, Christian Scheuemann

A 40-year-old woman developed spontaneous cerebrospinal fluid (CSF) rhinorrhea, possibly as a result of a significant remote cranial trauma. Magnetic resonance imaging (MRI) revealed a nonspecific fluid intensity in a space-occupying lesion in the sphenoid sinus; the lesion extended into the left lateral recess (figure 1). Magnetic resonance cisternography revealed fluid intensity and a meningoencephalocele with bulging meninges in the left lateral sphenoid recess (figure 2). In order to confirm the suspected cranial trauma, conventional contrast cisternography with computed tomography (CT) was performed (figure 3). CT cisternography identified dehiscence of the left lateral sphenoid recess, which contained contrast medium that had drained into the nasal cavity (figure 3).

[FIGURES 1-3 OMITTED]

Trans-sphenoidal meningoencephaloceles are usually congenital anomalies, although cranial trauma as a cause has been reported. (1) The trans-sphenoidal type is the least common type of encephalocele, accounting for 5% of encephaloceles that are seen in the base of the skull. (2)

Surgical treatment of CSF rhinorrhea secondary to a middle fossa encephalocele that extends into the lateral recess of the sphenoid sinus differs from the surgical strategy followed for more medial sphenoid fistulae. Fistulae that involve the lateral recess of the sphenoid sinus require a transcranial approach for direct visualization and obliteration of the bone defect, whereas fistulae that involve the central portion of the sphenoid sinus can be successfully obliterated via a trans-sphenoidal approach. (3)

References

(1.) Jabre A. Tabaddor R, Samarawerra R. Transsphenoidal meningoencephalocele in adults. Surg Neurol 2000;54:183-7: discussion 187-8.

(2.) Schick B, Draf W, Kahle G, et al. Occult malformations of the skull base. Arch Otolaryngol Head Neck Surg 1997:123:77-80.

(3.) Landreneau FE, Mickey B, Coimbra C. Surgical treatment of cerebrospinal fluid fistulae involving lateral extension of the sphenoid sinus. Neurosurgery 1998;42: 1101-4; discussion 1104-5.

From the Department of Radiology, Louisiana State University Health Sciences Center, New Orleans.