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Published on: May 12, 2011
Medial and lateral horns of the lower eyelid retractors
Hirohiko Kakizaki1, Raman Malhotra, Takashi Nakano
1Department of Ophthalmology, Aichi Medical University, Nagakute, Aichi, Japan. cosme@d1.dion.ne.jp
Purpose:
To reveal the medial and lateral horns of the lower eyelid retractors, measure the horn width, and examine the racial differences of the horns between white and Japanese cadaver specimens.
Methods:
Five lower eyelids of 3 white cadavers aged from 81 to 89 years at death and 7 lower eyelids of 5 Japanese cadavers aged from 66 to 85 years at death were studied.
Results:
All lower eyelid retractors in both races showed medial and lateral horns. The average width of the medial horns was 4.3 mm in whites and 4.2 mm in Japanese, and that of the lateral horns was 6.5 mm in whites and 6.2 mm in Japanese. The lateral horns were statistically larger than the medial horns irrespective of race. There were no statistical differences between the races.
Conclusions:
The lower eyelid retractors has medial and lateral horns, the latter of which is larger. They are analogous to those of the levator aponeurosis, but did not demonstrate racial differences with regard to horn width.
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