Abstract
Purpose: :
To evaluate corneal graft survival, intraocular pressure control, and postoperative complications after penetrating keratoplasty (PK) and pars plana Ahmed Glaucoma Valve (AGV) insertion in a subset of patients with coexisting glaucoma and corneal disease.
Methods: :
Retrospective chart review at one institution of 19 eyes (18 patients) who received PK and AGV placement through the pars plana after a complete pars plana vitrectomy. 13 eyes had simultaneous PK and AGV placement or tube repositioning from the anterior chamber into the posterior segment, while 5 eyes had posterior AGV placement no more than four months prior to PK, and 1 eye had posterior AGV placement no more that four months after PK. Visual acuity, intraocular pressure (IOP), clinical corneal findings, postoperative complications, and additional surgeries were recorded and analyzed. Failure of the corneal graft was defined as loss of corneal clarity on clinical exam or need for repeat PK, while failure of the AGV was defined as 5 > IOP > 21 mm Hg (with or without glaucoma medications) at last follow-up or complications requiring removal of the Ahmed device or the need for further glaucoma surgery.
Results: :
Nine of the eyes (47.4%) had previous PKs, with an average of 1.8 PK per eye. 8 of the eyes had previous glaucoma surgery. The average postoperative follow-up was 24.6 months (range: 5 - 106). The mean preoperative IOP was 21.3 mm Hg (SD ± 5.5), and IOP at last follow-up was 17.1 mm Hg (SD ± 7.7). At last follow-up, 58% of the corneal grafts (11/19) remained clear, and the 8 grafts that failed averaged a longevity of 27.1 months (SD ± 27.8). By last follow-up, best-corrected visual acuity had improved by at least one line in 25.3% of eyes (5/19) as compared to preoperative values. 58% of eyes (11/19) demonstrated glaucoma success at last follow-up. Two eyes required repeat PKs, 4 eyes required Ahmed plate or tube revisions, and one patient eventually required AGV removal. There were no retinal complications during follow-up.
Conclusions: :
Ahmed Glaucoma Valve placement through the pars plana represents a viable treatment option for visual rehabilitation in eyes with coexisting glaucoma and corneal disease. At last follow-up, the majority of the corneal grafts remained clear, and the majority of the eyes maintained IOP control. Graft decompensation, when it did occur, likely reflects the associated ocular morbidity and clinical complexity of this circumscribed cohort of eyes.
Keywords: cornea: clinical science • intraocular pressure