Punctum plug and method for treating keratoconjunctivitis sicca (dry eye) and other ophthalmic aliments using same

• US 3,949,750 A
• Filed: 10/07/1974
• Issued: 04/13/1976
• Est. Priority Date: 10/07/1974
• Status: Expired due to Term

• Current Assignee: Jerre M. Freeman
• Original Assignee: Jerre M. Freeman
• Inventors: Freeman, Jerre M.
• Primary Examiner(s): Medbery, Aldrich F.
• Application Number:
  US05/512,430
• Time in Patent Office: 554 Days
• Field of Search: 128/260, 128/131, 128/130, 128/271, 128/341, 128/1 R, 128/350 R, 128/DIG. 25
• US Class Current: 424/427
• CPC Class Codes: A61F 9/0017 implantable in, or in contact with, the eye, e.g. ocular inserts
• CPC Class Codes: A61F 9/00772 Apparatus for restoration of tear ducts

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 inserter tool for facilitating the grasping, manipulation and insertion of the plug. The punctal plug has been found useful in treating keratoconjunctivitis sicca (dry eye) and is believed to be suitable for treating other ophthalmic ailments where retention of lacrimal fluid on the surface of the eye and in the lacrimal lake is desired or where sustained release of an ophthalmic medication to the eye by using the plug as a medication carrier is desired.

Claims

1. A removable rod-like plug for blocking lacrimal fluid flow through the punctum and associated canaliculus of the human eye comprising:

a projecting tip portion having a maximum cross-sectional dimension in the range of about 1.0 to 1.4 mm which is sufficient to occlude the canaliculus when inserted therein, a middle neck portion of smaller cross-section than the largest part of said tip portion with a maximum dimension in the range of about 0.6 to 0.8 mm and adapted to be tightened upon by the punctum sphincter ring, said tip and neck portions cooperating with said canaliculus and punctum sphincter ring respectively to prevent accidental extrusion of said plug, and a head portion of larger cross-section than said neck portion and adapted to rest on the surface of the punctal aperture and prevent said plug from passing down into the canaliculus, with the overall length of said plug comprised of said tip, neck and head portions being not less than about 3.2 mm.

2. The punctum plug of claim 1 wherein said respective tip, neck and head portions thereof are each of circular cross-section and said tip portion is of generally forwardly tapered configuration for dilating the canaliculus when inserted therein.

3. The punctum plug of claim 1 wherein said plug is unitary and comprised of tissue-tolerable, readily sterilizable, inert material selected from the group consisting of polytetrafluorethylene and hydroxyethylmethacrylate hydrophilic polymer.

4. The punctum plug of claim 1 wherein said head portion thereof is comprised of a medicament-impregnable porous material for storing and slowly dispensing an ophthalmic fluid medication to the eye while said plug is inserted into the punctal opening.

5. A means for removably blocking lacrimal fluid flow through the punctum and associated canaliculus of the human eye comprising a plug-shaped body portion of cross-section sufficient to at least substantially occlude the punctal aperture and associated vertical canaliculus when inserted therein, and an enlarged head portion so sized relative to said aperture that when said plug is inserted into the punctum and canaliculus it will rest upon the surface of the punctal aperture, said head portion being of a porous tissue-tolerable polymer material and containing a reservoir therein of an ophthalmic fluid medication which is slowly dispensed to the surface of the eye by the leaching action of the lacrimal fluids thereon.

6. The punctum plug of claim 5 wherein said head portion is of material selected from the group consisting of polytetrafluorethylene and hydroxyethylmethacrylate hydrophilic polymer.

7. A method for treating and alleviating keratoconjunctivitis sicca (dry eye) resulting from insufficient production or excessive drainage of lacrimal fluid comprising the steps of:

a. dilating the punctum and associated vertical canaliculus to about two and one-half times or greater normal size;

b. thereafter inserting a removable rod-like plug into the punctum and associated vertical canaliculus to occlude the punctal opening and prevent the passage of lacrimal fluid therethrough, said plug being sized and configured so as to be firmly retained in said punctal opening against accidental extrusion by the frictional engagement therewith of the distended canaliculus and punctum sphincter ring; and

c. maintaining the plug in place for a sustained and effective period of time to treat said condition.

8. The method of claim 7 further including the step of dispensing an ophthalmic fluid medication on a sustained release basis to the eye from a reservoir of such medication stored in said plug and dispensed through openings therein.

9. A method for treating ophthalmic ailments requiring the topical application of a fluid medication to an afflicted eye over repeated or sustained periods of time, said method comprising the steps of:

a. impregnating with said medication at least a portion of a plug element of size and configuration adapted to be removably fitted into the punctum and associated vertical canaliculus of an afflicted eye; and

b. inserting said medicament-impregnated plug into said punctum and associated vertical canaliculus to be retained therein for a sufficient period of time to dispense an effective amount of said medication to said afflicted eye.

10. The method of claim 9 wherein, prior to said insertion step (b), said punctum and associated vertical canaliculus are dilated to about 21/2 times or greater their normal size.