January/February 2009 - Louisiana Society of Health-System ...

Louisiana Society of Health-System Pharmacists Page 6
Central Serous Chorioretinopathy
Nicole Ehrlicher, PharmD Candidate & Lisa DiGioia-Ross, PharmD
Central serous chorioretinopathy or central serous
retinopathy (CSR) is a disease that involves a retinal detachment
of the macular layers of the eye in which fluid leaks into the
subretinal space. The detachment can cause tears or breaks in
the retinal pigment epithelium which leads to the build up of this
endogenous fluid or edema. CSR is usually idiopathic in nature
and self-limiting with about 80% of patients regaining 20/25
vision or better. Unfortunately, patients with CSR have a 40-
50% risk of recurrence in the same eye. CSR usually results in
blurred, distorted vision or metamorphopsia, a gray blind spot in
the central vision, and/or flashes of light or photopsia.
CSR occurs most commonly in males between the ages
of 20-55 who are considered to have Type A personalities.
People with Type A personalities are usually extremely
competitive, impatient, time conscious, aggressive, and
sometimes considered workaholics. CSR is uncommon in the
African American population; however, it is extremely severe in
the Hispanic and Asian populations. Women tend to develop
CSR at a later age compared to men. Patients diagnosed after
the age of 50 usually have the disorder bilaterally and usually
have a history of corticosteroid use or severe uncontrolled
hypertension.
Even though the pathophysiology of CSR is not well
understood, stress seems to play a role in the development of the
disease. Stress causes stimulation of the sympathetic nervous
system which in turn can cause local weakness in the Bruch’s
membrane (a transparent inner membrane of the choroid which
is in contact with retinal pigment epithelium). This subsequently
leads to the leakage of fluid secondary to a defect in the retinal
pigment epithelium and ultimately, could cause a focal
detachment of the retina. Another hypothesis claims the
pathophysiology involves an abnormal ion transport across the
retinal pigment epithelium which can result in focal choroidal
vasculopathy. Other hypothetical systemic causes include
hypertension, organ transplantation, systemic lupus
erythematosus (SLE), Cushing’s syndrome, steroid use, and
gastroesophogeal reflux disease (GERD). All of these systemic
conditions are associated with a high level of stress and cortisol
release. Also there has been a correlation between Helicobacter
pylori and CSR. Approximately 70% of CSR patients are
infected with Helicobacter pylori. Further studies are needed to
determine if an infection with Helicobacter pylori is a risk
factor.
It has been shown in many clinical trials that prolonged
corticosteroid use can exacerbate central serous retinopathy.
Corticosteroids play a role in the expression of adrenergic
receptors which when stimulated by the sympathetic nervous
system, cause the release of catecholamines (epinephrine,
norepinephrine, and dopamine). This release occurs mainly
during stressful situations and therefore, may contribute to the
pathogenesis of CSR. A study of 50 CSR patients showed that
26 patients (52%) had a history of exogenous steroid use. In
addition, most retinas reattach spontaneously once systemic
corticosteroids are discontinued. Systemic corticosteroid use is
the most prevalent risk factor for developing or exacerbating
CSR and should be avoided in patients with this disease.
There has also been some speculation that Viagra®
(sildenafil) may have a relationship to CSR, although a causal
relationship has not been established. However, a retrospective
study showed that 8 out of 11 patients taking sildenafil and
diagnosed with CSR had improved vision upon discontinuation.
Therefore, most physicians do not recommend the use of
sildenafil in patients with refractory CSR. Other agent that
should be avoided in patients with CSR includes aspirin and
caffeine plus other stimulants and possibly non-steroidal antiinflammatory
drugs (NSAIDs). In addition, since elevated
opiate levels from use of heroin or morphine have also been
associated with CSR it would be best to avoid using these agents
as well.
Patients with CSR can present with symptoms of visual
loss, metamorphopsia, decrease or distortion in central vision,
scotoma, loss of color perception and loss of contrast sensitivity.
Most patients complain of objects being distorted in some way
and miniaturized. However, CSR can be asymptomatic and is
usually unilateral. Some classic signs of CSR include local
serous detachment of the retina usually within the region of the
macula, serous fluid void of any lipid or heme, retinal
epithelium irregularities, and possible subretinal fibrin
deposition. CSR is commonly diagnosed by using optical
coherence topography (OCT) and fluorescein angiogram (FA).
If the OCT shows subretinal fluid, retinal pigment epithelium
detachment, neurosensory macula detachment, and any retinal
atrophy resulting from a chronic disease state, it may be
suggestive of CSR. The FA is able to detect leaks at the level of
the retinal pigment epithelium, and in about 10-15% of patients,
a classic “smoke stack” appearance of the leak will be present.
Even though CSR has serious signs and symptoms, the
prognosis is usually good if the disease in caught in the early
stages. As mentioned earlier, about 80% of patient will have
20/25 vision or better leaving only 20% failing to recover vision
of 20/30 or better. Most of the patients failing to regain adequate
vision usually have a chronic form of CSR secondary to another
uncontrolled disease (i.e. hypertension or SLE). Patients with
chronic CSR usually have chronic serous retinal detachment
caused by severe retinal pigment epithelium atrophy and only
regain about 20/200 vision. Even if the disease is detected early,
there is a risk of about 50% recurrence of CSR in the same the
eye.
The treatment and management of CSR is not well
defined. Laser photocoagulation is commonly used in the
treatment of CSR to cauterize the subretinal leak areas and
prevent fluid from escaping. Laser photocoagulation is usually
only used during the following complications of CSR: a serous
detachment of greater than four months or recurrence of CSR in
the same or opposite eye with visual deficits. Laser
photocoagulation is also used if the serous detachment is more
than 300 micrometers from the center of the fovea. If laser
treatment is concentrated too close to the macula, it can leave a
permanent blind spot. If the leak is too close to the macula, then
transpupillary thermotherapy has been used as a lower risk
alternative laser treatment. Laser treatment has been shown to
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