The sensorineural apparatus of the human eyelid

TY - JOUR

T1 - The sensorineural apparatus of the human eyelid

AU - Munger, B L

AU - Halata, Zdenek

PY - 1984

Y1 - 1984

N2 - The present study describes a complex array of sensory nerve terminals in the human eyelid. In many respects this pattern of innervation resembles that previously described in the rhesus monkey, but in other respects it is unique to man. The most prominent nerve terminals are a complex array of lanceolate and circular Ruffini and free nerve endings that envelop the eyelashes. In addition, Merkel cells have not been conclusively identified to date in other nonhuman primate nonsinus hairs. The external root sheath collar contains Merkel cells, and dermal Merkel cells have also been identified close to the collar. The anterior cutaneous surface of the eyelid contains small vellus hairs with typical lanceolate, Ruffini, and free nerve endings resembling those of primate facial skin. Scattered Meissner and scant simple corpuscles as well as scattered free nerve endings (FNEs) can be identified on the occlusal surface of the eyelid. Intraepithelial as well as dermal FNEs were most easily identified in this region in areas lacking other corpuscular receptors. Corpuscular receptors are especially common at the occlusal/conjunctival angle. The inner or conjunctival surface of the eyelid appears to be a glandular epithelium, whereas in the rhesus monkey it is stratified squamous epithelium. This epithelium needs additional study. In summary, the present study confirms the unique sensory neural status of the human eyelid and verifies the presence of Ruffini nerve terminals by light and electron microscopy and of free nerve ending terminals at least by light microscopy, as well as a unique pattern of innervation of the human eyelash.

AB - The present study describes a complex array of sensory nerve terminals in the human eyelid. In many respects this pattern of innervation resembles that previously described in the rhesus monkey, but in other respects it is unique to man. The most prominent nerve terminals are a complex array of lanceolate and circular Ruffini and free nerve endings that envelop the eyelashes. In addition, Merkel cells have not been conclusively identified to date in other nonhuman primate nonsinus hairs. The external root sheath collar contains Merkel cells, and dermal Merkel cells have also been identified close to the collar. The anterior cutaneous surface of the eyelid contains small vellus hairs with typical lanceolate, Ruffini, and free nerve endings resembling those of primate facial skin. Scattered Meissner and scant simple corpuscles as well as scattered free nerve endings (FNEs) can be identified on the occlusal surface of the eyelid. Intraepithelial as well as dermal FNEs were most easily identified in this region in areas lacking other corpuscular receptors. Corpuscular receptors are especially common at the occlusal/conjunctival angle. The inner or conjunctival surface of the eyelid appears to be a glandular epithelium, whereas in the rhesus monkey it is stratified squamous epithelium. This epithelium needs additional study. In summary, the present study confirms the unique sensory neural status of the human eyelid and verifies the presence of Ruffini nerve terminals by light and electron microscopy and of free nerve ending terminals at least by light microscopy, as well as a unique pattern of innervation of the human eyelash.

U2 - 10.1002/aja.1001700205

DO - 10.1002/aja.1001700205

M3 - SCORING: Journal article

VL - 170

SP - 181

EP - 204

IS - 2

M1 - 2

ER -