Despite the importance of anatomic variations in the muscular bands around the orbicularis oculi muscle (OOc), little is known about them. The morphology and variations therein of the medial muscular band of the OOc were thus examined in the current study. Sixty-one hemifaces of Korean cadavers were dissected to enable examination of the anatomic organization of the muscles around the OOc. A medial muscular band of the OOc was observed in 40 cases (65.6%). Three patterns of attachment were found. In type A (14 cases, 23%), it attached to the frontal belly without being attached to the medial canthal tendon; in type B (14 cases, 23%), it originated from the medial canthal tendon at the lower portion of the OOc and inserted into the cheek skin, and in type C (12 cases, 19.7%), it was also observed to insert into the cheek skin and attach to the frontal belly without being attached to the medial canthal tendon. The distance between the inferior edge of the OOc and the subnasale was 16.3 (SD, 4.3) mm and 14.5 (SD, 4.4) mm in cases with and without a medial muscular band, respectively. A space was observed on the inferolateral side of the OOc in about 67.2% of cases. These findings regarding the medial muscular band of the OOc increase further the anatomic variations associated with this region. In addition, it appears that this medial muscular band of the OOc can help to prevent drooping of the OOc.
From the *Division in Anatomy and Developmental Biology, Department of Oral Biology, Human Identification Research Center, Brain Korea 21 Project, Yonsei University College of Dentistry, Seoul; and †Department ofOral Anatomy, School of Dentistry, Pusan National University, Busan, South Korea.
Received January 10, 2011.
Accepted for publication April 2, 2011.
Address correspondence and reprint requests to Hee-Jin Kim, DDS, PhD, Room 601, Department of Oral Biology, Yonsei University College of Dentistry, 250 Seongsanno, Seodaemun-gu, Seoul 120-752, South Korea; E-mail: firstname.lastname@example.org
J.-T.P. and K.-H.Y. contributed equally to this work.
This study was supported by a faculty research grant of Yonsei University College of Dentistry for 2010 (6-2010-0088).
The authors report no conflicts of interest.