Glaucoma drainage for animals

Abstract

Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube, encompassing at least the extension of foldability

Description

Field of invention

[0001] The invention relates to a glaucoma drainage device (gonioimplant) for animals to drain elevated intraocular pressure. This drainage system consists of a central hemishell as a base with conical, interrupted, circular ridges on both sides and an attached silicone tube. Known state of the art

[0002] Glaucoma drains—with and without a valve—are used in both human and veterinary ophthalmology (Baerveldt, Molteno, Ahmed, White; Schwartz et al., pp. 181f). Both systems exhibit similar drainage characteristics (after approximately 3–6 weeks postoperatively) (Gelatt, Gilger, Kern, p. 1121). They serve to lower intraocular pressure by draining aqueous humor from the anterior chamber of the eye into the subconjunctival area or behind the eyeball. The implant base is fixed to the sclera beneath the conjunctiva (Gelatt, Gilger, Kern, pp. 1121ff). After several months postoperatively, a capsule regularly forms around the baseplate, preventing further drainage and thus causing intraocular pressure to rise again. Background of the invention

[0003] If an animal develops glaucoma (increased intraocular pressure) that can no longer be adequately treated with medication, then either a drainage pathway for the aqueous humor must be created or the cells that produce the aqueous humor (ciliary bodies) must be partially destroyed (Gelatt, Gilger, Kern, p. 1120). Early-stage glaucoma is not very painful, but as the disease progresses, the increasing intraocular pressure makes it extremely painful. The optic nerve head and the retina can be so severely damaged that the animal becomes irreversibly blind or at least suffers partial vision loss. Characteristic clinical signs of existing glaucoma include eye pain, corneal edema, dilated pupils, enlarged eyeball, and vision loss (Maggs, Miller, Ofri, pp. 281ff). If an animal's vision is impaired or completely lost, it is no longer viable in the wild.Domestic and farm animals typically exhibit changes in behavior due to pain, or because the cornea becomes cloudy or the eye enlarges. These treatment-resistant glaucomas are treated microsurgically by specially trained veterinarians, veterinary ophthalmologists. This involves creating an additional drainage pathway that directs the aqueous humor into the subconjunctival or retrobulbar space, or destroying some ciliary bodies using laser or cryotechnology to reduce aqueous humor production (Gelatt, Gilger, Kern, pp. 1120ff; Wilson, pp. 346ff; Riva, pp. 362ff). Since intraocular pressure (IOP) can temporarily increase after laser treatment, a drainage system is often implanted as well (Komäromy, p. 732). These glaucoma surgeries are most commonly performed on dogs, cats, and horses, but also on wild and zoo animals.

[0004] The status of pets has changed significantly in recent decades. Dogs, for example, were previously used primarily as guard and hunting dogs, while today they also find their place as service dogs (police, customs), service and therapy dogs, or in dog sports and in families.

[0005] As in human ophthalmology, intraocular pressure is measured using highly developed medical devices. In most cases, it can initially be treated pharmacologically (Maggs, Miller, Ofri, p. 280f).

[0006] In veterinary ophthalmology, however, glaucoma is often only recognized in an advanced stage because communication with the patient is not possible (providing information about visual acuity and pain levels), and only the altered behavior of the animal or changes in the eye lead to the examination.

[0007] The diagnostic examination includes tonometry, goniometry, ophthalmoscopy, and 20-60 MHz ultrasonography (Maggs, Miller, Ofri, p.281ff).

[0008] The pathogenesis of glaucoma can be genetic or age-related, a consequence of a pre-existing condition, or even caused by trauma.

[0009] In summary, this means that there are very good diagnostic methods available for diagnosing glaucoma in animals and treating it pharmacologically. Treatment-resistant glaucomas require microsurgical intervention, or alternatively, the eye must be removed (enucleation) to alleviate the pain.

[0010] To date, various gonioimplants have become established on the market (see the patents listed below), but these are often encapsulated by an impermeable capsule after a certain period (usually between 5 and 12 months) (Gelatt, Gilger, Kern, p. 1124; Komáromy et al., p. 12). This problem has not yet been addressed in product design: all these implants are characterized by a smooth surface on which cell growth can easily occur, thus allowing the formation of the fibrotic capsule, and materials have only been partially selected for their long-term biocompatibility (Ayyala et al., Parts 1 and 2).

[0011] This problem is solved by the design defined in claim 1 and by the use of a material which is used for the manufacture of intraocular lenses and which has not led to any foreign body reactions. Detailed description of the invention

[0012] The invention achieves, by introducing several (at least three) radially arranged bead rings on the upper and lower surfaces, that capsule formation around this convex-concave base plate is made more difficult and thus delayed or prevented.

[0013] The invention is foldable and can therefore be implanted through a smaller incision into the subconjunctival pocket (between the conjunctiva and sclera).

[0014] The invention is predominantly made of soft, hydrophobic acrylate, which is used as a long-term implant for the manufacture of intraocular lenses.

[0015] The invention achieves a seepage cushion-like effect by introducing the interruption of these ring ridges.

[0016] The invention achieves a more moderate reduction in intraocular pressure through the introduction of the oozing cushion effect.

[0017] The invention allows for faster wound healing due to the smaller surgical incision.

[0018] The invention is provided with several holes to allow the circulation of the ocular fluid and thus additionally prevent capsule formation.

[0019] The invention has two holes on the side of the silicone tube through which the implant is fixed by means of a suture to ensure a secure fit of the implant. QUOTES INCLUDED IN THE DESCRIPTION

[0020] Cited patent literature US 4,457,757 (Molteno) US 5,071,408A (Ahmed) EP 2 789 318 A3 (van der Mooren, Bogaert, Jain) - (Baerveldt) US 4,554,918 (White)

[0021] Cited non-patent literature K. Gelatt, B. C. Gilger, T. J. Kern, Veterinary Ophthalmology, Wiley-Blackwell, 5th edition, 2013, Ames, Alabama, USA D.J.Maggs, P.E.Miller, R.Ofri, Slatter's fundamentals of Veterinary Ophthalmology, Elsevier, 6.Auflage, 2018, St.Louis, Missouri, USA R.Wilson, D.D.Dees, L.Wagner, B.E.Monheit, D.O'Gan, Use of a Baerveldt gonioimplant for secondary glaucoma in a horse, Equine Veterinary Education, July 2015, S.346-351 K.S.Schwarz, R.K.Lee, S.J.Gedde, Glaucoma drainage implants: a critical comparison of types, Current opinion in Ophthalmology 2006, 17:181-189 R.S.Ayyala, L.E. Harman, B.Michelini-Norris, L.E.Ondrovic, E.Haller, C.E.Margo, S.X.Stevens, Comparison of Different Biomaterials for Glaucoma Drainage Devices, Arch Ophthalmol 1999, Vol117, Feb1999, S.233-236 und Teil 2 Arch Ophthalmol. 2000; Vol 118, S.1081-1084 I.Riva, G.Roberti, F.Oddone, A.GP Konstas, L.Quaranta, Ahmed glaucoma valve implant: surgical technique and complications, Clinical Ophthalmology 2017, 11:357-367 AMKomäromy, D.Bras, DWEsson, RLFellman, SDGrozdanic, L.Kagemann, PEMiller, SEMoroi, CEPlummer,JSSapienza, et al., The future of canine glaucoma therapy, Veterinary Ophthalmology, Vol 22, Issue 5, 2019 ,pp.726-740 QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 4,457,757

[0020] US 5,071,408A

[0020] EP 2 789 318 A3

[0020] US 4,554,918

[0020] Cited non-patent literature

[0000] Baerveldt, Molteno, Ahmed, White; Schwartz et al, S.181f

[0002] Gelatt, Gilger, Kern, S.1121

[0002] Gelatt, Gilger, Kern, S.1121ff

[0002] Gelatt, Gilger, Kern, S. 1120

[0003] Maggs, Miller, Ofri, S.281ff [0003, 0007] Gelatt, Gilger, Kern, S.1120f; Wilson, S.346ff; Riva, S.362ff

[0003] Maggs, Miller, Ofri, S.280f

[0005] Gelatt, Gilger, Kern, S.1124

[0010] Ayyala et al, Teil1 und 2

[0010] KNGelatt,BCGilger, TJKern, Veterinary Ophthalmology, Wiley-Blackwell, 5.Auflage,2013, Ames lowa, USA

[0021] DJMaggs, PEMiller, R.Ofri, Slatter's fundamentals of Veterinary Ophthalmology, Elsevier, 6.Auflage, 2018, St.Louis, Missouri, USA

[0021] R.Wilson, DDDees, L.Wagner, BEMonheit, D.O'Gan, Use of a Baerveldt gonioimplant for secondary glaucoma in a horse, Equine Veterinary Education, July 2015, S.346-351

[0021] K.S.Schwarz, R.K.Lee, S.J.Gedde, Glaucoma drainage implants: a critical comparison of types, Current opinion in Ophthalmology 2006, 17:181-189

[0021] R.S.Ayyala, L.E. Harman, B.Michelini-Norris, L.E.Ondrovic, E.Haller, C.E.Margo, S.X.Stevens, Comparison of Different Biomaterials for Glaucoma Drainage Devices, Arch Ophthalmol 1999, Vol117, Feb1999, S.233-236

[0021] Teil 2 Arch Ophthalmol. 2000; Vol 118, S.1081-1084

[0021] I.Riva, G.Roberti, F.Oddone, A.GP Konstas, L.Quaranta, Ahmed glaucoma valve implant

[0021] surgical technique and complications, Clinical Ophthalmology 2017, 11:357-367 A.M.Komäromy, D.Bras, D.W.Esson, R.L.Fellman, S.D.Grozdanic, L.Kagemann, P.E.Miller, S.E.Moroi, C.E.Plummer,J.S.Sapienza, et al., The future of canine glaucoma therapy, Veterinary Ophthalmology, Vol 22, Issue 5, 2019 ,S.726-740

[0021]

Claims

[1] Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube comprising at least the extension of foldability [2] Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube comprising at least the extension of foldability in different sizes for different species [3] Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube comprising at least the extension of foldability in different sizes for different species with bilateral, circular and interrupted bead rings. [4] Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube comprising at least the extension of the foldability in different sizes for different species with bilateral, circular and interrupted bead rings and various holes in the base plate. [5] Gonioimplant for animals as a convex-concave base plate made of hydrophobic acrylate with an attached silicone tube comprising at least the extension of the foldability in different sizes for different species with bilateral, circular and interrupted bead rings and various holes in the base plate as well as two holes next to the silicone tube for fixation. [6] A gonioimplant according to claim 1-3 fulfills the function of a drainage cushion in the sense of a throttled outflow of the aqueous humor. [7] A gonioimplant according to claim 1-3 is in particular designed for dogs, cats and horses.