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Fuchs' is one of the most common dystrophies that we diagnose in eye care. The clinical picture of
Fuchs' dystrophy reveals the presence of corneal guttata as the remaining endothelial cells spread to
cover as much of the cornea's back surface as possible. Guttata associated with Fuchs' dystrophy typically
present bilaterally and are often located centrally. (Be careful not to confuse Fuchs'-related guttata
with peripheral guttata, which simply could be caused by age-related changes. Specular microscopy might be
the only way to correctly differentiate the findings.)
Patients with Fuchs' dystrophy often present with a chief complaint of
blurred vision in the morning.
Also, they may occasionally demonstrate other associated findings, such as corneal haze, edema or even bullae.
An absolute diagnosis of Fuchs' dystrophy can be confirmed via specular microscopy. In this instance,
specular microscopy often will reveal early signs of stress on the endothelium as well as a cell density
measurement of less than 800. However, in the meantime, the slit lamp findings, pachymetry changes and duration
of morning blur will assist you in determining when a patient may need to be educated about future surgical
treatment options.
It is best to educate Fuchs' dystrophy patients as early as possible. You must inform them that it is a
progressive, hereditary condition that will eventually require surgical intervention. The good news is that
surgical options for Fuchs' dystrophy have improved vastly during the last several years. Contemporary
surgical options, such as endothelial transplants or DSEK (Descemet's scraping endothelial keratoplasty),
no longer require sutures or re-epithelialization and do not cause significant induced astigmatism. You can
also use hyperosmotic drops, such as Muro 128 (sodium chloride, Baush + Lomb) or FreshKote
(Focus Laboratories), to help reduce edema and alleviate some of the endothelial cell stress—both of
which may prolong the need for corneal transplant.
Until you see significant symptom progression, you should schedule the patient for follow-up every six months.
Also, it is best to schedule such examinations in the morning, because it will help you better determine the
patient's true level of visual debilitation. Although specular microscopy is the best way to monitor patients
with Fuchs' dystrophy, other methods to monitor disease progression include pachymetry measurement and
morning visual acuity assessment.
The bottom line:
- If the patient's vision deteriorates to 20/50 or worse and he or she is unable to function normally
(or his or her vision does not recover within two to three hours after waking in the morning), consider
referring the patient to a corneal surgeon for DSEK.
- When the patient's corneal thickness increases to 600µm, it is time to begin discussing a
transplant (assuming average corneal thickness is approximately 550µm). If/when the cornea reaches
640µm, most patients will require surgical intervention.
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