Spontaneous cerebrospinal fluid rhinorrhoea is a rare clinical entity. The accurate localisation of the leakage site is essential for surgical planning. Imaging techniques such as high-resolution computed tomography (CT), CT cisternography and magnetic resonance cisternography in variable combinations are performed for this purpose. This pictorial essay aims to present the spectrum of imaging findings in cases of spontaneous cerebrospinal fluid rhinorrhoea, which may be useful for radiologists in the determination of the site of cerebrospinal fluid leakage.
Adult ; Cerebrospinal Fluid Rhinorrhea ; diagnostic imaging ; pathology ; surgery ; Humans ; Magnetic Resonance Imaging ; Male ; Posture ; Tomography, X-Ray Computed

INTRODUCTION: Isolated oval window atresia (OWA) is a rare cause of congenital conductive middle ear deafness and may be overlooked owing to the normal appearance of the external ear. This anomaly has been previously described, although the published numbers with both imaging and surgical findings are few. Our aim is to correlate the imaging features of OWA with intraoperative findings. MATERIALS AND METHODS: This is a single-centre retrospective evaluation of patients who were diagnosed with OWA and who received surgery from January 1999 to July 2006. No new case was diagnosed after 2006 to the time of preparation of this manuscript. High resolution computed tomography (HRCT) imaging of the temporal bones of the patients were retrospectively evaluated by 2 head and neck radiologists. Images were evaluated for the absence of the oval window, ossicular chain abnormalities, position of the facial nerve canal, and other malformations. Imaging findings were then correlated with surgical findings. RESULTS: A total of 9 ears in 7 patients (two of whom with bilateral lesions) had surgery for OWA. All patients had concomitant findings of absent stapes footplate with normal, deformed or absent stapes superstructure and an inferiorly displaced facial nerve canal. HRCT was sensitive in identifying OWA and associated ossicular chain and facial nerve abnormalities, which were documented surgically. CONCLUSION OWA is a rare entity that can be diagnosed with certainty on HRCT, best visualised on coronal plane. Imaging findings of associated middle ear abnormalities, position of the facial nerve canal, which is invariably mal-positioned, and associated deformity of the incus are important for presurgical planning and consent.