Methods: Sixteen orbits were dissected from sixteen fixed, adult human cadavers. Microscopically, we identified the main trunks of the infratrochlear, supratrochlear, and supraorbital nerves and all branches that projected toward the upper eyelid. The number, size, and distribution of nerve branches were recorded.
Results: The branches of the infratrochlear, supratrochlear, and supraorbital nerves covered a wide range in the upper eyelid. The mean numbers of branches/nerve were 1.6 ± 1.2, 3.2 ± 1.5, and 2.6 ± 1.4, respectively. The branches of the infratrochlear nerve were distributed throughout the medial area of the upper eyelid. Those of the supratrochlear nerve were distributed throughout the medial and central areas, and the palpebral branches of the supraorbital nerve were distributed throughout the central and lateral areas of the upper eyelid. The lateral branches of the supraorbital nerve and the cutaneous branches of the lacrimal nerve were distributed in the lateral region of the orbit.
Conclusions: We show that upper eyelid sensation is transmitted mainly by the supratrochlear and supraorbital nerves, and we provide a map of the distribution of upper eyelid sensory nerves. This precise anatomical knowledge about upper eyelid sensory nerves will facilitate pain control and help minimize nerve injuries during surgery.