Paranasal sinus access implant devices and related products and methods

A method for making a paranasal access implant device, wherein the paranasal implant device comprises:

• a proximal end at a first longitudinal end of the device to be disposed in the lacrimal apparatus when the device is implanted and a distal end at a second longitudinal end of the device to be disposed in the paranasal sinus when the device is implanted;
• a length longitudinally along the implant device between the proximal end and the distal end in a range of from 8 millimeters to 50 millimeters;
• a conduit, located between the proximal end and distal end, to be disposed through a fistula between the lacrimal apparatus and the paranasal sinus when the device is implanted, the conduit comprising a distal portion to be disposed in the paranasal sinus when the implant device is implanted;
• a head adjacent the proximal end and connected with the conduit, the head including at least one flanged portion to be disposed in the lacrimal apparatus when the device is implanted, the flanged portion having a distal side to be disposed toward tissue adjacent the fistula when the implant device is implanted and a proximal side opposite the distal side;
• an internal passage through the head and the conduit, to provide a fluid communication path between the lacrimal apparatus and the paranasal sinus when the device is implanted, the internal passage having a width through at least a portion of the conduit in a range of from 0.5 millimeter to 2.5 millimeters;
• wherein:
• the flanged portion of the head has a concave undercut portion on the distal side, and the method comprises modifying a preliminary form of the implant device, the preliminary form including preliminary forms for the head, conduit and internal passage, with the preliminary form of the head including a preliminary form of the concave undercut portion, and the modifying comprises enlarging the head by adding a layer of added material to the proximal side and the distal side of the head, wherein the layer of added material is at least twice as thick on the proximal side of the head as on the concave undercut portion of the distal side of the head.