An unusual case of complete anatomical compartmentalization of the cavernous sinus in a patient with bilateral Type D cavernous dural arteriovenous fistulae is described. This anatomical anomaly isolated the anterior cavernous sinus and orbital venous system, which was primarily responsible for the patient's clinical presentation. The compartmentalization of the cavernous sinus also limited options for definitive endovascular therapy to a transvenous approach via the superior ophthalmic vein.