A case report and review of the temporal bone (TB) collection in the Department of Otolaryngology at SUNY Health Science Center in Syracuse demonstrated the occurrence of arachnoid granulations (AGs) in the posterior fossa surface of the TB and their role in cerebrospinal fluid (CSF) otorrhea. A large AG responsible for CSF otorrhea in a 64-year-old man was excised with soft tissue repair of the dural defect. Sixteen of 188 TBs (8.5%) in the collection contained 24 AGs ranging in size from 0.07 to 80.65 mm3. Nine AGs (37%) were small (less than 1 mm3) and did not demonstrate enlargement. Twelve (50%) were of intermediate size (2.50 to 9.32 mm3), and three (13%) were large (49.82 to 80.65 mm3). The intermediate and large AGs were associated with bone erosion and a high incidence of communication with a pneumatized mastoid complex (serous otitis media or meningitis). These findings suggest that AGs of sufficient size to produce bone erosion are the primary responsible lesions in adult-onset spontaneous CSF otorrhea.

No abstract

The author's series of 168 consecutive cases of chronic otitis media from the years 1965 to 1972 were reviewed with regard to the occurrence and management of pathological fistulae in the bony labyrinth. Fourteen cases (incidence 8.3%), of which nine involved only the semicircular canals and five involved primarily the cochlear wall occasionally associated with a semicircular canal fistula, were examined particularly in terms of postoperative sensorineural hearing loss following removal of cholesteatoma matrix from the fistula. The results indicated that the matrix can be removed with reasonable safety from most small semicircular canal fistulae. Only when the cholesteatoma matrix is firmly adherent to a large area of membranous semicircular canal is removal not recommended. When the cholesteatoma was removed from three cochlear fistulae, sensorineural hearing loss resulted. In two cases with cochlear fistula, hearing was preserved when the cholesteatoma matrix was not removed from the fistulized area. These results have been used to formulate guidelines for the surgical management of pathological fistulae of the bony labyrinth.

No abstract

Four locations for congenital cerebrospinal fluid fistula in the region of a normal labyrinth are reviewed. A congenital leak may occur through the petromastoid canal, a wide cochlear aqueduct, Hyrtl's fissure, or the facial canal. A fistula through the initial segment of the fallopian canal was successfully repaired in a two-year-old boy who had three episodes of meningitis following otitis media. Knowledge of these four sites of congenital defects provides a guideline for the surgeon in the identification and repair of cerebrospinal fluid leaks in the region of the labyrinth.