2 FIBROMUSCULAR TRANSVERSE LIGAMENTS RELATED TO THE LEVATOR PALPEBRAESUPERIORIS - WHITNALLS-LIGAMENT AND AN INTERMUSCULAR TRANSVERSE LIGAMENT

Background: This study was performed to reinvestigate the detailed ana tomy of the connective tissues related to the levator palpebrae superi oris (LPS). Materials and Methods: One hundred and twenty human orbits were prepared macroscopically or with the help of an operational micr oscope. Connective tissues related to the LPS were measured, removed, and prepared for histology, Different staining procedures including im munohistochemistry for alpha-smooth muscle actin were applied to analy ze the quality of these tissues. Results: Preparation consistently rev ealed two definite fibromuscular transverse ligaments related to the L PS, i.e., Whitnall's ligament (WL) and a definite intermuscular transv erse Ligament (ITL) underlying the LPS, The ITL exhibited a greater an terio-posterior extension than WL, In sagittal section, the ITL was ob served slightly more posterior in the orbit than WL, Histologically, b oth ligaments consisted of collagenous fibers, elastic fibers, and smo oth muscle fibers. WL was connected with the LPS by sagittal fibroelas tic connecting strands. Conclusions: Two transverse ligaments of fibro muscular tissue, WL and the ITL, form a sleeve superior and inferior t o the LPS, This sling is supposed to assist the LPS in its action and should be preserved at ptosis surgery. (C) 1996 Wiley-Liss, Inc.