Central serous retinopathy (CSR), also known as central serous chorioretinopathy (CSC or CSCR), is an eye disease which causes visual impairment, often temporary, usually in one eye. When the disorder is active it is characterized by leakage of fluid under the retina that has a propensity to accumulate under the central macula. This results in blurred or distorted vision (metamorphopsia). A blurred or gray spot in the central visual field is common when the retina is detached. Reduced visual acuity may persist after the fluid has disappeared.
The disease is considered of unknown cause. It mostly affects white males in the age group 20 to 50 and occasionally other groups. The condition is believed to be exacerbated by stress or corticosteroid use.
Causes
CSR is a fluid detachment of macula layers from their supporting tissue. This allows choroidal fluid to leak beneath the retina. The buildup of fluid seems to occur because of small breaks in the retinal pigment epithelium.
CSR is sometimes called idiopathic CSR which means that its cause is unknown. Nevertheless, stress appears to play an important role. An oft-cited but potentially inaccurate conclusion is that persons in stressful occupations, such as airplane pilots, have a higher incidence of CSR.
CSR has also been associated with cortisol and corticosteroids. Persons with CSR have higher levels of cortisol. Cortisol is a hormone secreted by the adrenal cortex which allows the body to deal with stress, which may explain the CSR-stress association. There is extensive evidence to the effect that corticosteroids (e.g. cortisone), commonly used to treat inflammations, allergies, skin conditions and even certain eye conditions, can trigger CSR, aggravate it and cause relapses. In a study documented by Indian Journal of Pharmacology, a young male was using Prednisolone and began to display subretinal fluid indicative of CSR. With the discontinuation of the steroid drop the subretinal fluid resolved and did not show any sigN of recurrence. Thus indicating the steroid was the probable cause of the CSR. A study of 60 persons with Cushing's syndrome found CSR in 3 (5%). Cushing's syndrome is characterized by very high cortisol levels. Certain sympathomimetic drugs have also been associated with causing the disease.
Evidence has also implicated helicobacter pylori (see gastritis) as playing a role. It would appear that the presence of the bacteria is well correlated with visual acuity and other retinal findings following an attack.
Evidence also shows that sufferers of MPGN type II kidney disease can develop retinal abnormalities including CSR caused by deposits of the same material that originally damaged the glomerular basement membrane in the kidneys.
Diagnosis
The diagnosis usually starts with a dilated examination of the retina, followed with confirmation by optical coherence tomography and fluorescein angiography. The angiography test will usually show one or more fluorescent spots with fluid leakage. In 10%-15% of the cases these will appear in a "classic" smoke stack shape.
Indocyanine green angiography can be used to assess the health of the retina in the affected area which can be useful in making a treatment decision. An Amsler grid can be useful in documenting the precise area of the visual field involved. The affected eye will sometimes exhibit a refractive spectacle prescription that is more far-sighted than the fellow eye due to the decreased focal length caused by the raising of the retina.
Treatment
Differential diagnosis should be immediately performed to rule out retinal detachment, which is a medical emergency. Additionally, a clinical record should be taken to keep a timeline of the detachment.
Most eyes with CSR undergo spontaneous resorption of subretinal fluid within 3â€"4 months, recovery of visual acuity usually follows. Any ongoing corticosteroid treatment should be tapered and stopped, where possible. It is important to check current medication, including nasal sprays and creams, for ingredients of corticosteroids, if found seek advice from a medical practitioner for an alternative.
Treatment should be considered if resorption does not occur within 3â€"4 months, spontaneously or as the result of counselling.
Oral Medications
Sprionolactone is a mineralocorticoid receptor antagonist that has been proven to help reduce the fluid associated with Central Serous Retinopathy. In a study noted by Acta Ophthalmologica also noted that the Spironolactone improved the visual acuity over the course of 8 weeks.
Epleronone is a mineralocorticoid receptor antagonist that has been proven to reduce the subretinal fluid that is present in Central Serous Retinopathy. This is a similar treatment to Spironolactone. In a study noted in International Journal of Ophthalmology, results showed Epleronone decreased the SRF both horizontally and vertically over time. Though after stopping the medication the fluid also appeared to return and patients needed further treatment.
Low dosage ibuprofen has been shown to quicken recovery in some cases, whilst avoiding naturally occurring blood thinners such as garlic, turmeric, cinnamon, which can enhance leakage from capillaries behind the retina.
Topical Treatment
Though no topical treatment has been proven to be effective in the treatment of Central Serous Retinopathy. Some doctors have attempted to use nonsteroidal topical medications to reduce the subretinal fluid associated with CSR. The nonsteroidal topical medications that are sometimes used to treat CSR are, Ketorolac, Diclofenac, or Bromfenac.
Lifestyle Changes
People who have irregular sleep patterns, type A personalities, sleep apnea, or systemic hypertension are more susceptible Central Serous Retinopathy, as stated in Medscape “The pathogenesis here is thought to be elevated circulating cortisol and epinephrine, which affect the autoregulation of the choroidal circulation,†With management of these lifestyle patterns, it has been shown that the fluid associated with Central Serous Retinopathy can spontaneously resolve with the management of the cortisol and epinephrine levels. Melatonin has been shown to help regulate sleep in people who have irregular sleep patterns (such as 3rd shift workers, or overnight employees), in turn regulating cortisol and epinephrine levels to manage CSR.
Laser Treatment
Laser photocoagulation, which effectively burns the leak area shut, may be considered in cases where there is little improvement in a 3 to 4-month duration, and the leakage is confined to a single or a few sources of leakage at a safe distance from the fovea. However, for many cases the leak is very near the central macula, where photocoagulation would leave a blind spot or the leakage is widespread and its source is difficult to identify. Foveal attenuation has been associated with more than 4 months' duration of symptoms, however a better long-term outcome has not been demonstrated with laser photocoagulation than without photocoagulation. Laser photocoagulation can permanently damage vision where applied. Carefully tuned lasers can limit this damage. Even so, laser photocoagulation is not a preferred treatment for leaks in the central vision and is considered an outdated treatment by some doctors.
In chronic cases, transpupillary thermotherapy has been suggested as an alternative to laser photocoagulation where the leak is in the central macula.
Photodynamic therapy (PDT) with verteporfin has shown promise as an effective treatment with minimal complications. Follow up studies have confirmed the treatment's long-term effectiveness including its effectiveness for the chronic variant of the disease. Indocyanine green angiography can be used to predict how the patient will respond to PDT.
Yellow micropulse laser has shown promise in very limited trials.
A Cochrane review seeking to compare the effectiveness of various treatment for CSR found low quality evidence that half-dose PDT treatment resulted in improved visual acuity and less recurrence of CSR in patients with acute CSR, compared to patients in the control group. The review also found benefits in micropulse laser treatments, where patients with acute and chronic CSR had improved visual acuity compared to control patients.
Prognosis
The prognosis for CSR is generally excellent. Whilst immediate vision loss may be as poor as 20/200 in the affected eye, clinically over 90% of patients regain 20/30 vision or better within 6 months.
Once the fluid has resolved, by itself or through treatment, visual acuity should continue to improve and distortion should reduce as the eye heals. However, some visual abnormalities can remain even if visual acuity is measured at 20/20, and lasting problems include decreased night vision, reduced color discrimination, and localized distortion caused by scarring of the sub-retinal layers.
Complications include subretinal neovascularization and pigment epithelial detachment.
The disease can re-occur causing progressive vision loss. There is also a chronic form, titled as type II central serous retinopathy, which occurs in approximately 5% of cases. This exhibits diffuse rather than focalized abnormality of the pigment epithelium, producing a persistent subretinal fluid. The serous fluid in these cases tends to be shallow rather than dome shaped. Prognosis for this condition is less favorable and continued clinical consultation is advised.
See also
- Diabetic retinopathy
- Hypertensive retinopathy
- Macular degeneration
- Posterior vitreous detachment
References
