Punctum plug and method for treating keratoconjunctivitis sicca (dry eye) and other ophthalmic aliments using same
US3949750A · kind A · utility
Inventor
Key dates
| Filing date | Oct 7, 1974 |
| Grant date | Apr 13, 1976 |
| Priority date | — |
| Expiry date | Oct 7, 1994 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F9/0017
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A plug of suitable dimension and material is removably inserted into the upper and/or lower punctal apertures of the eye to block the opening and the attendant canaliculus so as to thereby prevent the drainage of lacrimal fluid therethrough. The plug is comprised of tissue-tolerable, readily sterilizable material, such as polytetrafluorethylene (Teflon), or hydroxyethylmethacrylate (HEMA) hydrophilic polymer, methyl methacrylate, silicon, stainless steel or other inert metal material. The rod-like plug is formed with an oversized tip or barb portion that dilates and blockingly projects into the canaliculus, a smaller neck or waist portion upon which the punctum sphincter ring tightens, and a relatively larger, smooth head portion which rests upon the top of the punctal opening and prevents the plug from passing down into the canaliculus. In some embodiments the plug is impregnated with or otherwise acts as a carrier vehicle for an ophthalmic medication which is stored and delivered on a sustained release basis to the eye. A method for inserting the plug into the punctal opening is described, utilizing a dilator tool for enlarging the punctum and associated canaliculus and an insert…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.