Intrathecal gadolinium-enhanced MR cisternography in the evaluation of CSF leakage

Abstract

Background and purpose: Radiologic identification of the location of the CSF leakage is important for proper surgical planning and increases the chance of dural repair. This article describes our experience in analyzing clinically suspected cranial CSF fistulas by using MR imaging combined with the intrathecal administration of a gadolinium-based contrast agent.

Materials and methods: A total of 85 consecutive patients with suspected CSF fistulas who presented with persistent or intermittent rhinorrhea or otorrhea lasting for more than 1 month between 2003 and 2007 were included in this study.

Results: We observed objective CSF leakage in 64 of 85 patients (75%). The CSF leak was located in the ethmoidal region in 37 patients (58%), in the superior wall of the sphenoid sinus in 8 patients (13%), in the posterior wall of the frontal sinus in 10 patients (15%), in the superior wall of the mastoid air cells in 6 patients (9%), and from the skull base into the infratemporal fossa in 1 patient (2%). Two patients (3%) showed leakage into >1 paranasal sinus.

Conclusions: MR cisternography after the intrathecal administration of gadopentate dimeglumine represents an effective and minimally invasive method for evaluating suspected CSF fistulas along the skull base. It provides multiplanar capabilities without risk of radiation exposure and is an excellent approach to depict the anatomy of CSF spaces and CSF fistulas.

Fig 1.

CSF rhinorrhea following head trauma in a 42-year-old woman. Coronal T1-weighted MR cisternogram obtained after intrathecal administration of gadopentetate dimeglumine (Gd-DTPA) shows contrast leakage (arrow) extending from the cranial subarachnoid space into the ethmoid air cell region from a defect in the right side of the cribriform plate.

Fig 2.

CSF rhinorrhea in a 39-year-old man after sellar region surgery. A, Coronal thin-section CT scan reveals a defect in the right side of the sphenoid sinus (arrow) and opacification of the right sphenoid sinus. B and C, Coronal and axial T1-weighted fat-saturated MR cisternograms obtained after the intrathecal administration of Gd-DTPA show contrast leakage (arrows) extending from the cranial subarachnoid space into the right sphenoid sinus.

Fig 3.

CSF rhinorrhea and otorrhea following head trauma in a 15-year-old adolescent boy. A, Axial thin-section CT scan shows a defect in the left petrous temporal bone (arrow) and opacification of the left middle ear cavity. B and C, Coronal and axial T1-weighted fat-saturated MR cisternograms show contrast leakage in the middle ear cavity and eustachian tube (arrows).

Fig 4.

CSF rhinorrhea following head trauma in a 32-year-old woman. A–C, Axial, coronal, and left parasagittal T1-weighted fat-saturated MR cisternograms obtained after the intrathecal administration of Gd-DTPA show contrast leakage (arrows) extending from the cranial subarachnoid space into the left infratemporal fossa.

Fig 5.

CSF rhinorrhea following head trauma in a 35-year-old man. A, Coronal thin-section CT scan reveals a defect in the roof of the sphenoid sinus (arrow) and opacification of the right sphenoid sinus. B, A coronal T1-weighted fat-saturated MR cisternogram obtained after the intrathecal administration of Gd-DTPA shows contrast leakage (arrow) extending from the cranial subarachnoid space into the right sphenoid sinus. C, After repair of the dural rupture, suspected CSF rhinorrhea recurred 1 week later and the patient underwent control MR cisternography. Images obtained in the first hour show probable leakage (arrow). D and E, Leakage becomes obvious in late images taken in the third and fifth hours (arrows).