Walsh & Hoyt: Clinical Manifestations

Dural CCFs usually occur in middle-aged or elderly women, but they may produce symptoms at any age, even in childhood or infancy, in both sexes. The symptoms and signs produced by these lesions are influenced by a number of factors, including the size of the fistula, location within the cavernous sinus, rate of flow, and especially whether drainage is posterior, anterior, or both. The route of drainage of the fistula is probably related to its basic anatomic configuration, although Grove postulated that many, if not all, fistulas initially drain posteriorly into the inferior petrosal sinus, basilar venous plexus, or both. He believed that when this normal pathway for drainage becomes thrombosed, the fistula begins to drain anteriorly, producing visual symptoms and signs. We and others have seen patients whose clinical course suggests that this theory is correct. Such patients initially may experience an acute isolated ocular motor nerve paresis, the evaluation of which reveals a posteriorly draining fistula. Shortly thereafter, the patients develop typical signs of an anteriorly draining fistula.