Paraparesis after low dose administration of fluorescein for endoscopic resection of an encephalocele: a case report.

The main causes for cerebrospinal fluid (CSF) leaks are known to be traumatic, iatrogenic, neoplastic, a meningoencephalocele, congenital bone defects, and spontaneous. Off-label intrathecal administration of fluorescein is widely used to localize a CSF leak. Complications are rare and low dose administration is described to be safe. In this case report, we present a case of a patient, who showed a CSF leak due to an encephalocele. Low dose fluorescein was applied intrathecally via lumbar catheter, the CSF leaks could be identified, and multilayered closure was performed. Postoperatively, the patient presented with motor and sensory deficits in the lower limbs which regressed only partially within 2 months. A possible explanation may be an increased local concentration of fluorescein, possibly on the basis of a preexisting lumbar spinal canal stenosis. To our knowledge, this is the first case in which a dose as low as 20 mg of fluorescein (2% saline mixture) led to persisting paraplegia. Therefore, the potential benefits and risks of the intrathecal fluorescein use in the detection of a CSF leak have to be discussed comprehensively prior to surgery.