CPT® Code 0449T

Insertion of aqueous drainage device, without extraocular reservoir, internal approach, into the subconjunctival space; initial device

The procedure described by CPT® Code 0449T involves the insertion of an aqueous drainage device into the subconjunctival space, utilizing an internal approach and specifically designed for the initial device. This intervention is primarily aimed at lowering intraocular pressure, which is crucial in preventing chronic conditions that can lead to optic nerve damage and potential vision loss. Elevated intraocular pressure is a significant risk factor for glaucoma and other ocular diseases, making this procedure vital for patients at risk. During the procedure, a gonioprism is employed to inspect the angle of the eye, allowing the surgeon to accurately locate the optimal position for the drainage device. Visualization of the trabecular meshwork is enhanced through the use of a gonioscope placed on a surgical microscope. A small incision is made in the temporal clear cornea to access the anterior chamber, which is subsequently filled with viscoelastic fluid to maintain its structure during the procedure. The drainage device is then inserted through this incision, traversing the anterior chamber to the pupillary margin, and is positioned into Schlemm’s canal via the trabecular meshwork. This meticulous process ensures that the device is correctly placed to facilitate effective drainage of aqueous humor, thereby helping to regulate intraocular pressure. The completion of this procedure is marked by the irrigation of the anterior chamber to clear any residual viscoelastic fluid and blood, followed by filling the chamber with saline to restore normal physiological pressure. This code specifically captures the initial insertion of the aqueous drainage device, distinguishing it from subsequent devices, which are reported under a different code (CPT® Code 0450T).