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Complications of Hydroxyapatite Use for Transnasal Closure of Cerebrospinal Fluid Leaks

Background Hydroxyapatite cement (HAC) was first introduced in the 1980s as a new method for bone replacement. However, it has not been recommended for use in areas exposed to air. Despite this, surgeries have been performed using HAC to close nasal/sinus cerebrospinal fluid (CSF) leaks or in the treatment of encephaloceles. Methods This study retrospectively documented four patients in whom HAC was used for closure of ethmoid and sphenoid sinus CSF leaks. Results This study showed that exposed hydroxyapatite could be extremely problematic resulting in scarring, chronic granulation, infection, and prolonged healing. Oftentimes, revision surgery was necessary to help control the reaction to hydroxyapatite. Conclusion Because of the frequent complications occurring with use of hydroxyapatite in the paranasal sinuses, its use should be limited to selected individuals in whom difficulty in achieving closure of the CFS leak could be anticipated and in whom adequate tissue coverage could be provided.