ABSTRACT
BACKGROUND: To report the histological microscopic anatomy of the interlower and postlower eyelid retractor (LER) fat pads. METHODS: In this experimental microscopic study, 31 exenterated orbits from 31 Japanese cadavers (19 right and 12 left; 15 male and 16 female; mean age of death, 81.0±8.8 years; range, 52-97 years) fixed in 10% buffered formalin were used. Masson trichrome was used to stain sagittal full sections of exenterated tissues. Microscopic examination of the lower eyelids was carried out. RESULTS: The exenterated orbits demonstrated the presence of the histological existence of inter-LER fat pad (80.6%) and post-LER fat pad (22.6%) in the lower eyelids. The inter-LER fat pad was thick and located between the anterior and posterior layers of the LER, where the blood vessels passed through in 18 specimens (72.0%). The post-LER pad was thin, subtle and located between the posterior layer of the LER and conjunctiva. CONCLUSION: This study reports a novel finding of the inter-LER and post-LER fat pads. Awareness of these fat layers provides surgeons with additional anatomical detail of lower eyelid anatomy.