The sympathetic innervation of the eyes and face: a clinicoanatomic review

Most of the details regarding the course of the sympathetic fibers to human ocular structures are based on anatomical and physiological studies in lower animals. While studying a clinical problem involving pericarotid sympathetic fibers, it became obvious that these animal observations cannot adequately explain the findings in human diseases affecting these pathways. An attempt was made, therefore, to clarify this situation. We were able to gather enough information from human clinical and experimental studies, from our own clinical observations, and from our cadaver dissections to conclude that these pathways are somewhat different from those which are usually described in the literature. Based on this information, we conclude that 1) the oculosympathetic fibers in man do not course through the tympanic plexus and/or trigeminal ganglion, and 2) the sweat glands of the face receive their innervation from both internal and external carotid sympathetic plexuses. We also have suggestive, but inconclusive, evidence regarding the final mode of distribution of these fibers to the dilator of the pupil and the smooth muscle portion (deep layer) of the levator palpebrae superioris muscle (superior tarsal muscle).