Regional Variations in Orbicularis Oculi Histology.

Laura Kopplin // Publications // Jan 01 2023

PubMed ID: 25794026

Author(s): Costin BR, Plesec TP, Kopplin LJ, Chundury RV, McBride JM, Levine MR, Perry JD. Regional variations in orbicularis oculi histology. Ophthalmic Plast Reconstr Surg. 2015 Jul-Aug;31(4):325-7. doi: 10.1097/IOP.0000000000000430. PMID 25794026

Journal: Ophthalmic Plastic And Reconstructive Surgery, Volume 31, Issue 4, 2015

PURPOSE To investigate and compare the histologic compositions of the pretarsal, preseptal, and orbital orbicularis oculi muscle (OOM) using nonpreserved, fresh-frozen, human cadavers.

METHODS The OOM was exposed using sharp and blunt dissection. A metric ruler was used to measure and mark 0.5 cm × 1 cm samples from each portion of the right, superior OOM. Samples were excised, fixed in formalin, and completely embedded in paraffin. Five-micrometer-thick, hematoxylin- and eosin-stained sections were generated for each sample and analyzed by an anatomical pathologist. The relative percentages of the 4 main tissue types (skeletal muscle, fibrous tissue, adipose tissue, and neurovascular tissue) were quantified.

RESULTS Forty-two samples were obtained from 14 Caucasian cadavers. On average, the pretarsal samples were composed of 83.5% skeletal muscle, 0.0% adipose, 5.0% neurovascular, and 11.5% fibrous tissue. Average preseptal OOM was 46.5% skeletal muscle, 12.7% adipose, 9.2% neurovascular, and 31.5% fibrous tissue. The orbital OOM was, on average, 42.7% skeletal muscle, 32.7% adipose tissue, 6.9% neurovascular, and 17.7% fibrous tissue.

CONCLUSIONS The OOM represents a histologically heterogeneous structure.