Osteomeningeal Fistulas: The Role of Isotope Cisternography

An osteomeningeal fistula (OMF) is defined as a break in the osteomeningeal barrier that allows cerebrospinal fluid (CSF) to flow into an air-filled cavity at the base of the skull. Diagnosing and localizing an OMC can be challenging and requires a combination of clinical, laboratory, and radiological findings. Isotope cisternography is an imaging technique used in nuclear medicine to study the dynamics and anatomical distribution of CSF, particularly to confirm the diagnosis of an OMC. To highlight the value of this examination in diagnosing this type of condition, we compiled data from the Nuclear Medicine department over a 46-year period on 12 patients with suspected BOM. Thirteen isotopic cisternographies were performed. The scintigraphic images revealed a leakage pathway in three cases but were unable to localize the BOM, and showed no direct or indirect signs of leakage in 10 cases. The systematic addition of a thread count increased the sensitivity of the examination by objectively identifying indirect signs of leakage in seven cases. The examination was negative in two cases.