Evaluation of Total and Perfused Blood Vessels in the Facial Nerve
The theory of primary and/or secondary ischemia leading to the vicious circle postulated by Hilger has become generllay accepted. In further animal experimental studies we examined the capillary network of the facial nerve of rabbits. We used, e.g., the method of plastination inaugurated by von Hagens and found a longitudinal and transverse network of capillaries supplying the nerve. The generally accepted theory is that only 25% of all capillaries are perfused in time. However, the normal capillary perfusion of the facial nerve and the amount of in vivo perfused capillaries are still unknown. In awake normocapnic rats we determined the density of the total and perfused capillary network of the facial nerve. The density of perfused capillaries was measured by two intravenous markers (fluorescein isothiocyanate globulin and Evans blue), the density of morphologically existing capillaries was determined according to an immunohistochemical fluorescence method which marked the capillary wall constituent fibronectin.