Microstructure and mechanical properties of synthetic brow-suspension materials

作者：Kwon Kyung Ah; Shipley Rebecca J; Edirisinghe Mohan^*; Ezra Daniel George; Rose Geoffrey E; Rayment Andrew W; Best Serena M; Cameron Ruth E

来源：Materials Science and Engineering: C , 2014, 35: 220-230.

DOI：10.1016/j.msec.2013.10.031

• Ptosis
• Brow-suspension
• Materials
• Microstructure
• Mechanical properties

Levator palpebrae superioris (LPS) is a muscle responsible for lifting the upper eyelid and its malfunction leads to a condition called "ptosis", resulting in disfigurement and visual impairment. Severe ptosis is generally treated with "brow-suspension" surgery, whereby the eyelid is cross-connected to the mobile tissues above the eyebrow using a cord-like material, either natural (e.g. fascia lata harvested from the patient) or a synthetic cord. Synthetic brow-suspension materials are widely used, due to not requiring the harvesting of fascia lata that can be associated with pain and donor-site complications.
The mechanical properties of some commonly-used synthetic brow-suspension materials were investigated namely, monofilament polypropylene (Prolene (R)), sheathed braided polyamide (Supramid Extra (R) II), silicone frontalis suspension rod (Visitec (R) Seiff frontalis suspension set), woven polyester (Mersilene (R) mesh), and expanded polytetrafluoroethylene (Ptose-Up). Each material underwent a single tensile loading to the failure of the material, at three different displacement rates (1, 750 and 1500 mm/min).
All the materials exhibited elastic-plastic tensile stress-strain behaviour with considerable differences in elastic modulus, ultimate tensile strength, elastic limit and work of fracture. The results suggest that, as compared to other materials, the silicone brow-suspension rod (Visitec (R) SFSS) might be the most suitable, providing relatively long-lasting stability and desirable performance. These findings, together with other factors such as commercial availability, cost and clinical outcomes, will provide clinicians with a more rational basis for selection of brow-suspension materials.

• 出版日期2014-2-1