Cerebrospinal fluid rhinorrhea: evaluation with metrizamide cisternography

Area of Science:

• Neurology
• Radiology
• Neurosurgery

Background:

• Cerebrospinal fluid (CSF) fistulae with rhinorrhea present a diagnostic challenge.
• Accurate localization of CSF leaks is crucial for effective surgical intervention.

Purpose of the Study:

• To evaluate the efficacy of metrizamide computed tomographic (CT) cisternography in diagnosing CSF fistulae.
• To determine the sensitivity and specificity of this imaging modality in identifying the exact site of CSF leakage.

Main Methods:

• Twenty-seven patients with suspected CSF fistulae underwent lumbar puncture with metrizamide injection.
• Direct coronal and axial CT scans of the skull base were performed.
• Results were assessed based on contrast passage, fracture visualization, and contrast in nasal cavities or pledgets.

Main Results:

• Metrizamide CT cisternography was positive in 15 of 27 patients, with the exact CSF leak site identified in 10.
• Traumatic fistulae were more common (21 cases) than spontaneous (6 cases).
• Ethmoidal and frontoethmoidal locations were the most frequent sites of leakage.

Conclusions:

• Metrizamide CT cisternography is a valuable tool for diagnosing CSF fistulae and pinpointing leak locations.
• The technique demonstrated higher diagnostic yield compared to other methods.
• Understanding diagnostic pitfalls like artifacts is essential for accurate interpretation.