Performing a concurrent capsule revision during a second nonvalved aqueous shunt procedure may aid in managing intraocular pressure (IOP) lowering, according to a case report published in Ophthalmology Glaucoma.
The study focuses on a single case of a patient with severe primary open-angle glaucoma in both eyes. The novel strategy combines the implantation of a nonvalved aqueous shunt with a procedure to revise a preexisting failed device.
The patient — an 87-year-old man — presented with severe bilateral primary open-angle glaucoma. He had undergone a failed superonasal trabeculectomy, superotemproal Ahmed FP7 in the anterior chamber, micropulse cyclophotocoagulation, and excisional goniotomy.
His visual acuity was approximately 20/30 OU and IOP was 24 mm Hg, despite being prescribed 4 IOP lowering medications. Humphrey visual field evaluation demonstrated a superior arcuate defect and an inferior hemifield defect.
The patient elected to undergo a second aqueous shunt procedure, while a concurrent Ahmed capsule revision was performed to enhance early postoperative IOP lowering.
At postoperative day 1, his IOP was 15 mm Hg with no medications. Prednisolone therapy 4 times daily was initiated. At postoperative day 3, IOP was 11 mm Hg with 2 medications; however, physicians increased his prednisolone every 2 hours while awake, to discourage encapsulation of the newly-revised Ahmed plate. By postoperative day 10, IOP was 6 mm Hg with 3 medications and a decrease of prednisolone back to 4 times per day.
By postoperative day 17, his IOP was 7 mm Hg on 1 med, with continuation of 4 times daily prednisolone therapy.
In-person follow-up at week 7 showed the ligature suture had dissolved, his IOP was 16 mm Hg with no medications, and fluid was observed overlying the plate, while the anterior chamber was described as “deep and quiet.”
The patient’s 3-0 Prolene ripcord suture was removed to fully open the Baerveldt. Prednisolone therapy was continued 4 times daily for 1 more week, then reduced to 3 times, 2 times, and 1 time daily for each of the next 3 weeks.
The prednisolone taper was completed by postoperative month 4, at which point IOP was 9 mm Hg with 2 medications. However, investigators report, the patient developed cystoid macular edema, requiring temporary topical prednisolone and ketorolac therapy.
By postoperative month 12, the patient’s vision was 20/30 with an IOP of 5 mm Hg and 2 medications. Medications were discontinued, and by month 14, IOP was 10 mm Hg with no medications.
“In patients with a previously failed valved aqueous shunt undergoing an additional non-valved aqueous shunt, consider performing a concurrent capsule revision,” the researchers explain. “The temporarily resurrected valved shunt may not remain fully functional indefinitely, but will at least provide transient early IOP-lowering until the non-valved aqueous shunt opens.”
Si Z, Theophanous C, Khanna S, Qiu M. Early IOP-control via capsule revision of a failed valve aqueous implant during concurrent placement of a non-valved aqueous implant. Ophthalmol Glaucoma. Published online September 6, 2021. doi:10.1016/j.ogla.2021.08.006