the present invention provides an a method for treating primary glaucoma and an anterior chamber shunt device to drain or divert aqueous humor in an animal &# 39 ; s eye from the anterior chamber into the frontal sinus cavity , in which the shunt device comprises a first end , adapted to be fitted with a guide needle , to be received within the anterior chamber following removal of the guide needle , and a second end having a crossbeam , bulb , slits and a plug tip to be received within the frontal sinus cavity , wherein the device permits aqueous humor communication from the anterior chamber to the frontal sinus cavity through the slit valves . fluid communication can be facilitated by intraocular pressure directing the aqueous humor into the slits , as described below . the embodiments of the present invention can be used to treat animals with primary glaucoma , particularly to drain or divert aqueous humor extraocularly and , more particularly to prevent postoperative hypotony . referring now to the drawings , in which like reference numerals are used to refer to the same or similar elements , fig1 shows the glaucoma shunt device ( 110 ) of the invention having tubing ( 120 ), and a guide needle ( 130 ) at a first end thereof , for communicating with the anterior chamber , and a plug tip ( 140 ) at an opposite end of the tubing . guide needle ( 130 ) is removed from tubing ( 120 ) and does not remain in the sinus . bulb ( 150 ) is connected to tubing ( 120 ) and anchors shunt ( 110 ) within the frontal sinus cavity . guide needle ( 130 ) does not remain in the sinus . slits ( 160 ) at 90 ° from bulb ( 150 ) to the plug tip ( 140 ) form a conduit for draining fluid from the anterior chamber of the eye . slits ( 160 ) are provided as one - way flow resisting valves in the tubing for allowing a flow of fluid to pass under resistance and in only one direction to the frontal sinus , whereby pressure in the anterior chamber is relieved while avoiding excessive outflow of fluid from the anterior chamber . crossbeam elements ( 170 ) are affixed to tubing ( 120 ) for anchoring the device to the outside ( periosteum ) of the frontal sinus . higher pressure aqueous humor inside the animal &# 39 ; s eye can naturally drain through glaucoma shunt device ( 110 ) via slits ( 160 ), and tubing ( 120 ) to the frontal sinus cavity . thus , intraocular pressure is relieved . fig2 is a side view of the device . guide needle ( 130 ) can be any conventional guide needle , for example , a 20 or 22 gauge precision guide needle available from becton dickinson . the guide needle is friction fitted to tubing ( 120 ) and is removable therefrom . the overall length of tube ( 120 ) is approximately 60 millimeters , with the proviso that length and tubing of the shunt ensure fluid flow from the eye directly into the frontal sinus cavity . tubing ( 120 ) has an inside diameter of approximately 0 . 64 millimeters and an outside diameter of approximately 1 . 2 millimeters . the outer and inner walls form a tubular channel to allow fluid flow from the eye into the frontal sinus cavity . phantom lines on fig2 display the tubular channel within the device . in all cases the length and the diameter of the tubing ( 120 ) must ensure fluid flow from the eye directly into the frontal sinus cavity . tubing ( 120 ) is made of any suitable material known in the art , such as , for example , medical grade radiopaque silicone rubber , and is flexible . at the opposite end of the device is a plug tip ( 140 ). the plug tip is made of any suitable material known in the art , such as , for example , silicone . bulb ( 150 ) is approximately 3 millimeters from plug tip ( 140 ). bulb ( 150 ) is made of any suitable material known in the art , such as , for example , clear silicone . bulb ( 150 ) provides an anchoring aspect to the shunt . bulb ( 150 ) is molded onto tube ( 140 ). bulb ( 150 ) has a rounded portion ( 151 ) and an angled portion ( 152 ). angled portion ( 152 ) forms a straight line at approximately 52 ° from a line perpendicular to tube ( 120 ) and rounded portion ( 151 ) has a diameter of approximately 4 mm . the maximum length of bulb ( 150 ) is 4 millimeters measured through the tubing . slits ( 160 ) are formed in the tubing between the end of angled portion ( 152 ) of bulb ( 150 ) to plug tip ( 140 ). slits ( 160 ) are at 90 ° degrees on the tubing and are approximately 3 millimeters in length . slits ( 160 ) form a conduit for draining fluid from the anterior chamber of the eye into the frontal sinus cavity . slits ( 160 ) provide one - way flow resisting valves in the tubing for allowing a flow of fluid to pass under resistance and in only one direction to the frontal sinus , whereby pressure in the anterior chamber is relieved while avoiding excessive outflow of fluid from the anterior chamber . the slits ( 160 ) drain the fluid in the anterior eye at an opening pressure between 18 – 20 mmhg . the slits ( 160 ) arc closed at pressures under 18 mmhg . thus , the outflow of aqueous humor is regulated at consistent opening and closing pressures and the volume of aqueous humor is controlled . the slits ( 160 ) may be adjusted to be open at a different pressure . furthermore , the consistent opening and closing pressures prevent postoperative hypotony because the level of volume of aqueous humor is regulated . any conventional means may be used to test and make the slits ( 160 ) in the tubing . fig3 is a top view of the device with labeled section a — a . crossbeams ( 170 ) with crossbeam ends ( 181 ) are provided . the materials used to make crossbeams ( 170 ) is made of any suitable material known in the art , such as , for example fluorocarbon suture material . the crossbeams are glued with silicone cement to the tubing approximately 11 millimeters from the plug tip ( 140 ) end of the device . however , a skilled artisan would readily understand that there are other ways to secure the crossbeams to the tubing . crossbeams ( 170 ) form a diameter of approximately 11 millimeters measured through the tubing . crossbeams ( 170 ) help to position device ( 110 ) by providing aids for anchoring the device to the outside surface ( periosteum ) of the frontal sinus . crossbeams ends ( 181 ) further define adhesives to aid in the anchoring . the materials used to make the adhesives are made of any suitable material known in the art , such as , for example medical grade silicone adhesive . the shape of shunt ( 110 ) allows easy insertion into the anterior chamber and the frontal sinus cavity and when the shunt is tugged back slightly during suturing the anterior chamber end , the crossbeams ( 170 ) and bulb ( 150 ) hold device ( 110 ) in position . fig4 is the perspective view of a — a of fig3 . the crossbeams further define left arm ( 182 ) and right arm ( 183 ). the left and right arms may be any shape and thickness that aids in suturing the device , but preferably are 0 . 28 millimeters thick . the arms are affixed to the tube approximately 0 . 152 millimeters from the inner wall of the tubular channel . although preferred embodiments of the present invention and modifications thereof have been described in detail herein , it is to be understood that this invention is not limited to those precise embodiments and modifications , and that other modifications and variations may be affected by one skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims .
the invention relates to a device and method for treating animals , such as humans and dogs , with primary glaucoma by draining or diverting aqueous humor extraocularly comprising a shunt implant wherein the length and tubing of the shunt ensure fluid flow from the eye directly into the frontal sinus cavity via tubing . the device has crossbeam aids in anchoring the device ; four slit valves to control fluid flow at required volume ; and bulb that anchors in the frontal sinus cavity . the device is preferably made of medical grade radiopaque silicone rubber , and is flexible . other improvements and a method for implanting the device are disclosed as well .