Punctal cannula
US6428502B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 8, 2000 |
| Grant date | Aug 6, 2002 |
| Priority date | — |
| Expiry date | May 8, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2210/0612
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A lacrimal cannula, which is used for the removal of plugs or obstructions from mammalian lacrimal canaliculi having a punctum, includes a body having a distal portion, a proximal portion, an external annulus disposed proximate the distal portion, and a hollow bore for fluid delivery from the distal portion. The external annulus has an outer diameter greater than the outer diameter of the distal portion. The distal portion is inserted into the mammalian punctum without dilating the punctum and the external annulus has a generally spherical geometry which forms a seal with the external surface of the punctum without dilating the punctum and without the necessity of forcefully pressing the cannula against the punctal tissue to create a seal. The distal portion also has a relatively short length so that the distal portion is easily inserted into the canaliculus without contacting the plug or obstruction and thus interfering with the formation of the punctal seal. The proximal portion is coupled to a hub for removably coupling the proximal portion to a conventional syringe. Once the external surface of the punctum is sealed, the cannula is then used to inject an ophthalmic fluid, which…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.