Ophthalmology Update - Cleveland Clinic

8
OPHTHALMOLOGY UPDATE 2009 SPECIAL EDITION
Case Study: DSAEK to Treat Amantadine-associated Corneal Edema
Christopher T. Hood, MD
Roger H.S. Langston, MD
William J. Dupps, Jr.,
MD, PhD
Presentation:
A 45-year-old Caucasian woman presented to the
Cole Eye Institute for management of corneal
edema. She described experiencing six months of
blurry vision in both eyes that was worse in the
morning and improved slightly throughout the day.
She denied redness, pain or photophobia. She was
being treated with Muro 128 ointment four times
daily in the right eye upon referral.
She denied any history of ocular trauma, surgery
or inflammatory disease. Her medical history was
significant for a longstanding diagnosis of multiple
sclerosis, for which she was taking baclofen, methyl-
phenidate, glatiramer acetate injection, neurontin,
amantadine, escitalopram oxalate and bupropion.
She denied any family history of eye disease.
Examination:
On examination, visual acuity was 20/800 in the right
eye and 20/400 in the left eye. Pupils were equal
in size and reactive, without an afferent pupillary
defect. Extraocular movements were full. Intraocular
pressures were 12 mm Hg in the right eye and 10
mm Hg in the left eye. Anterior segment examination
demonstrated normal eyelids, sclera and conjunc-
tiva. Bilateral diffuse stromal and epithelial edema
was observed with marked Descemet membrane
folds and pre-Descemet membrane opacification
without guttae (Figure 1). Ultrasound pachymetry
demonstrated a central corneal thickness of 867
µm in the right eye and 700 µm in the left eye. The
anterior chambers were deep and quiet. The iris
and lens were normal. Dilated fundus examination
of both eyes was unremarkable.
Diagnosis:
Diagnoses considered included Fuchs endothelial
dystrophy, endotheliitis, congenital hereditary
endothelial dystrophy and posterior polymorphous
dystrophy. In this case, a lack of guttae on examina-
tion combined with the historical features of no
previous intraocular surgery and amantadine use
led to the diagnosis of amantadine-associated
corneal edema. With the approval of the patient’s
neurologist, amantadine was discontinued and the
patient was followed for six weeks with minimal
improvement of the bilateral corneal edema.
Prednisolone acetate 1 percent was initiated four
times daily in both eyes and the patient was followed
for an additional six weeks. Although she demonstrated
initial improvement, best corrected vision
was 20/200 in both eyes.
The patient was offered Descemet’s stripping
automated endothelial keratoplasty (DSAEK) in the
right eye. After informed consent was obtained, she
underwent uncomplicated surgery. The patient, who
had no appreciable nuclear sclerosis, was left phakic
and was given topical pilocarpine 1 percent preoperatively.
Descemet stripping was performed under air,
and a donor lenticule was prepared on an artificial
anterior chamber and punched to 8.5 mm just prior to
insertion. Controlled tamponade of the graft against
the host stroma was performed with air infusion and
air-fluid exchange as described previously. 1 Three
months after surgery, the patient’s best corrected
visual acuity was 20/30+ in the right eye. Her cornea
was clear and compact with minimal anterior stromal
haze and the posterior donor lenticule was wellcentered
(Figure 2). DSAEK is planned in the left eye.
Discussion:
Amantadine was developed for short-term use as
an antiviral drug against influenza A, also is used
chronically to treat tremors and stiffness in Parkinson’s
disease and fatigue associated with multiple
sclerosis. The mechanism of its action is not well
understood. Reported ocular side effects include
visual loss, hallucination, oculogyric crises and
mydriasis. 2 Corneal side effects include superficial
punctuate keratitis, punctuate subepithelial opacities,
and epithelial and stromal edema. 2 Corneal edema
occurs from a few weeks to many years after commencing
amantadine therapy. 2-6 Clinical exam
demonstrates bilateral, diffuse stromal and microcystic
epithelial edema, without guttae or inflammatory