What is the relationship between cerebrospinal fluid (CSF) rhinorrhea and obstructive sleep apnea (OSA)?
Background: CSF rhinorrhea results from an osseous defect along the skull base with an associated anatomic disruption in the arachnoid and dura mater. Spontaneous CSF fistulae occur in the absence of a known inciting factor such as tumor, trauma, or iatrogenic injury. Independent of obesity, it has been suggested that OSA may also have a role in CSF rhinorrhea pathogenesis.
Study design: Single-institution, retrospective chart review of 126 patients who underwent surgical repair of encephaloceles and/or CSF rhinorrhea between 2000 and 2012.
Setting: Department of Otolaryngology–Head and Neck Surgery, University of North Carolina Memorial Hospitals, Chapel Hill, North Carolina.
Synopsis: Of the 126 patients, 70 had a spontaneous etiology. These patients were more likely to have an OSA diagnosis and on average had a significantly greater BMI, were significantly older, and were more likely to be female. Evidence of either empty or partially empty sella (a sella turcica containing no discernible pituitary gland or in which the pituitary gland is displaced inferiorly and flattened along the sellar floor) was seen on MRI of 55.4% of spontaneous CSF leak patients and of 24.3% of nonspontaneous CSF leak patients. The most common dehiscence region was found to be the ethmoid roof, inclusive of the fovea and cribriform, followed by the lateral sphenoid, central sphenoid, and frontal sinus; authors believe that the true incidence of OSA may be even higher than reported, as nine loud snorers without a definitive OSA diagnosis or an available polysomnogram were included in the non-OSA cohort. Limitations included an absence of CSF opening pressures, an absence of polysomnography results for every patient, and a lack of CPAP compliance usage data.
Bottom line: Patients with spontaneous CSF rhinorrhea are significantly more likely to have an OSA diagnosis. It remains to be discovered whether OSA is causative or a comorbidity among patients with elevated CSF pressures.
Citation: Fleischman GM, Ambrose EC, Huang BY, et. al. Obstructive sleep apnea in patients undergoing endoscopic surgical repair of cerebrospinal rluid rhinorrhea. Laryngoscope. 2014;124:2645-2650.
—Reviewed by Amy Eckner