Corneal Edema and Opacification

Publication Date: September 22, 2018
Last Updated: March 14, 2022


The impact of corneal edema on activities of daily living―particularly those influenced by ambient light levels at home, work, and during leisure activities―is often underappreciated. Standard measurement of visual acuity does not give a true representation of the patient’s functional vision. (, , )

Reduced vision in cases of corneal opacification is more often related to corneal surface irregularity than to the opacity itself. A refraction over a rigid gas-permeable (RGP) contact lens can be very helpful in determining if visual loss is due to a corneal surface irregularity.

Endothelial function is best evaluated by slit-lamp biomicroscopy examination and may be supported by changes in corneal thickness noted on serial pachymetric measurements performed at the same time of day. Specular microscopy is not a direct measure of endothelial function or functional reserve. When diffuse endothelial guttae are present on slit-lamp biomicroscopy examination, specular microscopy rarely provides any valuable information because it is difficult to image the endothelial cells.

Corneal pachymetry, measured in the morning, is a helpful indicator of the ability of the endothelium to regulate corneal hydration appropriately. Corneas that are abnormally thick in the morning hours may be less able to tolerate proposed intraocular surgery.

If the cataract surgeon or cornea specialist thinks that decompensation, if not imminent, is likely to occur in the near future, a discussion about modifying the intraocular lens (IOL) power calculation is worthwhile to adjust for changes induced by endothelial keratoplasty (specifically a hyperopic shift due to Descemet stripping automated endothelial keratoplasty [DSAEK] and less so with Descemet membrane endothelial keratoplasty [DMEK]). A full discussion of the added risks of subsequent corneal decompensation is very important in this group of patients and helps to shape their expectations with respect to their condition and the surgery.

Endothelial keratoplasty has supplanted penetrating keratoplasty as the procedure of choice in cases of endothelial failure in the absence of corneal scarring because patients achieve more rapid visual rehabilitation and reduction in rejection of the transplanted tissue.

Recommendation Grading




Corneal Edema and Opacification

Authoring Organization

Publication Month/Year

September 22, 2018

Last Updated Month/Year

June 9, 2022

Document Type


External Publication Status


Country of Publication


Document Objectives

Assess the degree of vision loss. Evaluate the degree of functional impairment and its effect on the patient’s activities of daily living. Identify the underlying ocular condition responsible for the corneal edema or opacification. Assess the potential for progression of the disorder, development of discomfort, and/or improvement of vision. Determine which optical, medical, or surgical treatment alternative is most appropriate.

Inclusion Criteria

Female, Male, Adolescent, Adult, Older adult

Health Care Settings

Ambulatory, Operating and recovery room, Outpatient

Intended Users

Optometrist, optician, nurse, nurse practitioner, physician, physician assistant


Diagnosis, Management

Diseases/Conditions (MeSH)

D015715 - Corneal Edema, D003316 - Corneal Diseases


corneal edema, Opacification, ocular diseases


Number of Source Documents
Literature Search Start Date
March 1, 2017
Literature Search End Date
June 1, 2018