Pseudophakic Bullous Keratopathy
Certain IOL designs, particularly iris-clip lenses (iris-fixated lenses with the optic anterior to the iris) and closed-loop flexible anterior chamber lenses as described in the Appendix, have been associated with an increased risk of corneal decompensation. Iris-clip lenses have been shown to contact the corneal endothelium during eye movement, whereas closed-loop ACIOLs are associated with endothelial cell loss, thought to be due to chronic inflammation and contact between the lens and peripheral corneal endothelial cells. Thus, these 2 lens types are no longer in clinical use.
Figure 11-13 Pseudophakic bullous keratopathy.
(Courtesy of Karla J. Johns, MD.)
With modern phacoemulsification and current IOLs, risk of corneal decompensation is increased with prolonged surgical time using high ultrasound energy, excessive use of ultrasound in the anterior chamber (as opposed to the iris plane or within the capsule), and inadequate protection of the corneal endothelium with OVDs (Fig 11-13). Underlying corneal endothelial dysfunction such as Fuchs corneal dystrophy also increases the risk of postoperative corneal edema. The surgeon can use OVDs to protect the corneal endothelium and avoid contacting the endothelium with instruments or lens particles.
Initial treatment of pseudophakic bullous keratopathy entails controlling postoperative inflammation while avoiding elevated IOP. As discussed earlier in this chapter (see the section Corneal Edema), topical hypertonic sodium chloride drops or ointment can be a conservative short-term treatment to decrease corneal edema. A bandage contact lens and topical antibiotics may be necessary for ruptured bullae.
Decreased vision, recurrent keratitis, and pain are possible indications for endothelial keratoplasty, which has been very successful in restoring clear corneas and improving vision. Bullae and associated pain may also be alleviated with phototherapeutic keratectomy, cautery of Bowman layer, anterior stromal micropuncture, or corneal crosslinking. When comfort is the primary goal in the eye with little or no vision potential, a Gundersen conjunctival flap or amniotic membrane graft is an option; neither of these carries the greater risks of keratoplasty. (See also BCSC Section 8, External Disease and Cornea.)
Excerpted from BCSC 2020-2021 series: Section 11 - Lens and Cataract. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.