Nearpoint stress

Normally, the accommodative process of the crystalline lens is smooth and effortless.  Sometimes, though, someone who always has had good far distance vision and then, after doing a few weeks or months of prolonged near work, suddenly notices that his/her far vision is beginning to blur, most likely is a victim of myopia (nearsightedness) induced by “nearpoint stress.”  Although nearpoint stress is more common in students, from elementary school through college, it can occur at any age in the eyes of somebody performing long periods of near work.

Besides eyelid twitching, eyestrain, and headaches, one of the first symptoms of nearpoint stress is noticed when looking up from a long period of close work, discovering that things are a little blurry across the room.  In the initial stages of nearpoint stress, far away objects will clear up quickly or gradually (as the ciliary muscles relax).  However, with maintained nearpoint stress over time, far distance vision will remain blurry (because the ciliary muscles no longer can completely relax).  Myopia will have begun to become “embedded” within the accommodative system of the eye(s), and far away vision will be compromised when doing such things as trying to read street or freeway signs at night or food section signs down the aisles of supermarkets.

The mechanics of nearpoint stress induced myopia vary from person to person.  In most cases, though, the intraocular ciliary muscle controlling the eye’s crystalline lens goes into a spasm (known as “ciliary spasm”)—temporary at first and then eventually, if the stress is not relieved, permanent—causing the lens of the eye to take on and lock into a “fatter” shape, resulting in myopia.  This is not equated with a deterioration of the ciliary muscle but, rather, is due to a continual overaction of this muscle.  When one changes one’s focus from far to near, the ciliary muscle contracts, causing the crystalline lens to accommodate.

Too much near work, without giving the eyes frequent and sufficient breaks to view things across the room or further away, may result in an “over-heating” of the ciliary muscle of the eye.  This excess heat can be transmitted into the vitreous humor and, over time, may cause pockets of this gel-like substance to soften.  Immobile organic debris (known as “floaters”), located in some areas of the vitreous, then may begin to move around.  If these particles migrate toward the center of the vitreous, they can cast shadows on the retina, resulting in the impression of “spots” or “dots” before the eyes.  Floaters tend to be more prevalent in people with high myopia.

Another consequence of prolonged near work can be a spasming of the ciliary muscle, which in turn can cause a constant overly convex shaping of the crystalline lens, which in turn will cause images to focus in front of the retina when viewing distant objects—myopia.  This is the most common cause of nearpoint stress induced myopia.

Often, rather than both eyes being overworked an equal amount, the brain will select the person’s dominant eye to perform a disproportionate amount of the near work, resulting in the onset or progression of myopia only or mostly in that eye.  To some extent, this difference in the eyes also can hinder one’s depth perception.  A thorough ocular examination by a qualified, knowledgeable eye doctor usually can detect even the slightest degree of nearpoint stress in an eye.

The primary means of preventing nearpoint stress should be to attempt to ease the strain on the ciliary muscles of the eyes during long periods of close work.  First and foremost, it is extremely important to keep objects viewed at near as far away as possible from the eyes.  This means it is essential to do these things:

sit up straight (rather than hunch over) when writing;
keep printed material away from the eyes (rather than bringing it close to the face) when writing; and
maintain at least an arm’s length distance between the eyes and a monitor (rather than leaning forward) when typing on a keyboard.

The closer an object is to the eyes, the more effort the ciliary muscles must exert for the eyes to focus clearly on that object, accordingly producing more intraocular muscle strain.  Reading and writing material should be kept at least 20 inches away from the eyes, and a computer monitor should be no closer than 25 inches away—the further, the better.  Occasionally a glare-free screen can be helpful in reducing ocular discomfort, but viewing a screen at a comfortable distance is advantageous in decreasing nearpoint stress induced myopia.

Usually, simply looking up across the room or out of a window frequently (for a few seconds every few minutes) will sufficiently relax the ciliary muscles enough to prevent nearpoint stress.  When looking up and away, if distant objects are blurry, this is a sign that nearpoint stress has been occurring.  One should not resume a near task at least until one’s far away vision has become clear.  Sometimes looking alternately from far to near and then to far again, back and forth a few times, will enhance the flexibility of the ciliary muscles and decrease the chance of a cilary spasm.

If temporary distance blur frequently is noticed after near work, it may be that a pair of weak “reading” glasses, prescribed by a qualified eye doctor, would be helpful in preventing or reversing myopia induced by nearpoint stress.  The idea behind such a lens prescription is that these convex lenses, worn only while performing near visual tasks, will refocus the entering light, thus doing a slight amount of the focusing for the crystalline lenses and removing some of the strain on the ciliary muscles.  This minor relief of tension, in most cases, is enough to prevent over-contraction of these intraocular muscles and, thus, avert a nearpoint stress event.  Prevention or reversing of nearpoint stress induced myopia, though, is much more likely to occur soon after the condition has been discovered rather than at a later point when the myopia has been embedded too deeply into the eyes’ focusing system.

It has been theorized that in some cases of nearpoint stress, the cornea of the eye takes on a “steeper” (more convex) shape, due to prolonged pressure behind it.  If so, the pressure may be due to an inordinate anterior-to-posterior thickening of the eye’s crystalline lens from focusing too much at near, inducing a compression of the aqueous fluid anterior to the lens and, thus, resulting in pressure on the posterior cornea.  That a change in corneal shape may be a factor in some types of nearpoint stress may be evidenced by the fact that rigid contact lenses can retard or stop the progression of myopia in many cases.  Apparently, in such a case, the rigid lens prevents the anterior cornea from becoming more convex and, thus, arrests the advancement of myopia in the eye.

If the latter pressure on the cornea can occur from nearpoint stress, similar pressure theoretically could occur behind the crystalline lens of the eye, being transmitted through the vitreous gel and then to the retina.  If so, it may be that in some cases the retina and the back of the eye gradually are pushed posteriorly, eventually resulting in a lengthening of the eyeball and in the onset or increase of myopia.

presbyopia:

After age 40 in most people, and by age 45 in virtually all, a clear, comfortable focus at a near distance becomes more difficult with eyes which see clearly (whether with or without glasses) at a far distance.  This normal condition is known as “presbyopia,” and it is due both to a lessening of flexibility of the crystalline lens and to a generalized weakening of the ciliary muscle which causes the lens to accommodate (change focus).  By the time one reaches age 65 or so, the crystalline lens is virtually incapable of changing shape.  Unless one is nearsighted, it is not possible to focus objects (such print on a page) clearly at even an arm's length distance.

Note that “presbyopia” is not the same as “hyperopia” (farsightedness).  Presbyopia is an age-related condition, resulting in difficulty keeping a clear, comfortable focus at a near distance, even with an eye which is not hyperopic (farsighted).  On the other hand, hyperopia is a refractive error which makes it more difficult than normal to maintain a focus at a near distance than at a far away distance at any age (although, if one has a moderate to high degree of hyperopia, even maintaining a clear focus far away is difficult).

Interestingly, the first symptom of presbyopia usually is not blurred print or eyestrain while reading.  Rather, one often observes that objects across the room appear momentarily blurry after looking away from a near distance (that is, after reading, writing, or viewing a computer screen for awhile).  This is because the crystalline lenses within the eyes have become less flexible than they used to be, resulting in their being less able to accommodate (change focus) from near to far.  With time, it will take longer and longer to refocus objects far away after having done close work.

Eventually, if presbyopic eyes are continued to be forced to focus unwillingly at near, one’s far vision will become and remain noticeably blurry.  For a person who never had to wear glasses to see clearly far away, myopia (nearsightedness) and/or astigmatism will have set in, requiring a far distance prescription in glasses or contact lenses to see clearly again.  For a person who already is myopic, the degree of nearsightedness will have increased, requiring a stronger lens prescription to regain clear vision.

A myopic (nearsighted) person with presbyopia often can remove his/her glasses to focus clearly at near or else can obtain multifocal or blended lenses to be able to focus clearly at far and near with the same pair of glasses.  If contact lenses are worn, it will be necessary to wear some type of reading prescription (in glasses) over the contacts to achieve and maintain a clear, unstrained focus at near.

For some people, one eye (usually the dominant eye) may be fit with a contact lens focusing that eye for far away and the other eye fit with a lens focusing that eye for near; this is called a “monovision” fit.  However, with this arrangement, one’s depth perception (which is important when driving) is compromised to some extent.

A hyperopic (farsighted) person with presbyopia generally must acquire reading glasses for near work or else multifocal or blended lenses for full-time wear.  In some cases, store-bought (non-prescription) reading glasses may be an option.  However, such glasses have equal strengths in the right and left lenses.  Since most people’s eyes have unequal refractive errors, the focusing between their two eyes will not be balanced when wearing non-prescription readers, and one or both eyes may experience eyestrain.  In some cases, a “monovision” contact lens arrangement also may be appropriate for a person with hyperopia.

The amount of presbyopia inevitably increases with age.  Therefore, the additional “plus power” of the lens strength required to maintain a clear, unstrained focus at near will need to be increased every few years to counteract the irreversible effect of the presbyopia.

cataract:

Normally, all the layers of the crystalline lens are clear, and light passes through it unobstructed.  However, with age or disease, as well as with a cumulative absorption of ultraviolet radiation over many years, the lens material can become cloudy, yellow, brown, and even opaque.  Anything in the lens which obstructs entering light is referred to as a “cataract.”  More than 50% of people over the age of 60 have some form of a cataract; and it is said that if one lives long enough, he/she will develop a cataract.  Some infants are even born with a “congenital” cataract which, if left untreated, can cause permanent visual impairment or blindness.

It is not possible to remove a primary cataract without irreparably damaging the crystalline lens within which the cataract is contained.  A laser cannot be used to remove a cataract, except as described later (in the case of a secondary cataract).  Therefore, cataract surgery involves removing most or all of the lens of the eye and replacing it with an artificial “intraocular lens” or “lens implant,” made of a hard plastic (polymethyl methacrylate or PMMA), silicone, acrylic, or hydrogel material.

Prior to the 1980’s, the entire crystalline lens was removed in a cataract surgery, called an “intracapsular” cataract extraction (ICCE).  Usually, this was performed using “cryoextraction,” where a cryoprobe froze the entire lens, permitting its complete removal.  Rarely is this done anymore; instead, an “extracapsular” cataract extraction (ECCE) is the routine type of cataract removal.  In the latter procedure, an opening is made in the front of the lens capsule.  Through this opening, the lens nucleus is removed, either as a whole or by dissolving it into tiny pieces and vacuuming out the pieces, a procedure called “phacoemulsification.”  Next, the lens cortex also is sucked out, leaving the lens capsule in place, and into the lens capsule is inserted the artificial lens implant.  (In the case of a rare intracapsular lens extraction, the implant lens is placed in front of the iris, rather than behind it, because there is no lens capsule to hold the implant in place.)

Approximately 1-2% of post-cataract extraction patients develop swelling in the area of the retina responsible for central vision (the macula).  This swelling occurs in cystoid spaces, and is referred to as cystoid macular edema.  Patients frequently describe blurred vision after an initial improvement following surgery.  Cystoid macular edema can occur as early as days following surgery and as late as several years.  Treatment options include observation, topical therapy, periocular injections, and surgery.

Naturally occuring carotenoids in the crystalline lens, lutein and zeaxanthin (molecular cousins of beta carotene and vitamin A), have been shown to reduce the risk of cataracts.  These pigments act as antioxidants within the lens, inhibiting the formation of free radicals which can damage lenticular material and contribute to the development of cataracts.  Thus, the greater the amount of these antioxidants, the less the risk of cataract formation.  Lutein and zeaxanthin are found particularly in yellow fruits and in green leafy vegetables (especially xanthophyll-rich vegetables such as spinach, kale, collard greens, and broccoli), in eggs, and as nutritional supplements.

secondary cataractBesides excessive tearing, symptoms associated with dry eyes can include the following:

eye irritation, scratchiness, grittiness, or pain,
redness of the eye(s),
a burning sensation in the eye(s),
a feeling of something in the eye(s),
eyes that feel “glued shut” after sleeping,
blurred vision, and
eye discomfort with contact lens wear.

There can be multiple causes of a dry eye condition, and these are some of the possibilities:

lid or blinking problems (for instance, an injury or stroke affecting one of the nerves which helps us blink),
reading or working at a computer screen for long periods of time,
medications like antihistamines, oral contraceptives, beta blockers, diuretics, tranquilizers, pain relievers, or antidepressants,
a dry climate (including heating and air conditioning in a home, airplane, or motel room), wind, UV radiation, tobacco smoke, and dust,
diseases such as rheumatoid arthritis, Sjogren’s syndrome, keratoconjunctivitis sicca, xerophthalmia, lupus erythematosus, Grave’s disease, diabetes, or scleroderma
hormonal changes accompanying menopause,
chemical, radiation, or thermal burns to the eye,
vitamin A deficiency,
aging, since the tear glands produce fewer tears as we age, and
idiopathic (unknown) causes.

A dry eye problem often can be relieved with the use of over-the-counter eyedrops which behave as “artificial tears” on the eyes.  These types of drops can soothe the eyes, moisturize dry spots, supplement tears, and protect eyes from further irritation.  Some drops are formulated to match the pH of human tears for added comfort.  Special ocular lubricant ointments, applied to the eyes for overnight use, also are available.

Artificial tears may be preserved or unpreserved.  Bottle contamination is less likely with preserved drops; however, an allergic reaction to the preservatives can occur.  If unpreserved eyedrops are used, care must be taken not to contaminate the bottle by touching the tip to any surface, including the eyeball.

Some eyedrops contain “vasoconstrictors” (chemicals such as tetrahydrozaline or naphazoline), which constrict the conjunctival blood vessels, thereby reducing the amount of redness on the surface of the eyes.  These drops may or may not contain a tear substitute component for red eyes, and overuse can cause eyes to become even more red (“rebound hyperemia”) due to a weakening of the muscles persistently constricting the blood vessels.

In certain cases, artificial tear drops do not relieve the discomfort due to dry eyes.  In such cases, if the discomfort is severe enough, other options are available.  The most common of these involves closing the tear ducts (drains).  Using either a silicone plug or scarring the tear duct closed by cauterization (with a “hot poker”) decreases or stops the passage of the tears into the tear ducts.  That way, any tears naturally produced or artificially placed into eyes will remain longer (until they evaporate).  It can be a very successful way to make irritated eyes with a chronic dry eye syndrome feel more comfortable.

THE MACULA

.The macula lutea is the small, yellowish central portion of the retina, and it is the area providing the clearest, most distinct vision.  When one looks directly at something, the light from that object forms an image on one’s macula.  A healthy macula ordinarily is capable of achieving at least 20/20 (“normal”) vision or visual acuity, even if this is with a correction in glasses or contact lenses.  Not uncommonly, an eye’s best visual acuity is 20/15; in this case, that eye can perceive the same detail at 20 feet that a 20/20 eye must move up to 15 feet to see as distinctly.  Some people are even capable of 20/10 vision, which is twice as good as 20/20.  Vision this acute may be due to there being more cones per square millimeter of the macula than in the average eye, enabling that eye to distinguish much greater detail.

fovea centralis
The very center of the macula is called the fovea centralis, an area where all of the photoreceptors are cones; there are no rods in the fovea.  The fovea is the point of sharpest, most acute visual acuity.  (The center of the fovea is the “foveola.”)  Because the fovea has no rods, small dim objects in the dark cannot be seen if one looks directly at them.  For this reason, to detect faint stars in the sky, one must look just to the side of them so that their light falls on a retinal area, containing numerous rods, outside of the macular zone.

There are about 110,000 to 115,000 cone cells in the fovea and only about 25,000 cones in the tiny foveola.  The macular/foveal area is the main portion of the retina used for color discrimination.  Color vision deficiencies, which occur in less than 8% of males and in less than 1% of females, are usually hereditary, although they also can result from certain diseases, injury, or as a side effect of some medications or toxins.

color vision

To see any color, the retinal cone cells first must be stimulated by light.  “Red-sensitive” cones are most stimulated by light in the red to yellow range, “green-sensitive” cones are maximally stimulated by light in the yellow to green range, and “blue-sensitive” cones are maximally stimulated by light in the blue to violet range.  Accordingly, due to their respective sensitivities to long (L), medium (M), and short (S) wavelengths, they also are referred to as “L” cones, “M” cones, and “S” cones.  Collectively, the photoreceptors in the human eye are most sensitive to wavelengths between 530 and 555 nanometers, which is bright green tending toward yellow.

“Red-sensitive” or “L” cones
 “Green-sensitive” or “M” cones


“Blue-sensitive” or “S” cones


The brain must compare the input from the three different kinds of cone cells, as well as make many other comparisons.  This comparison begins in the retina (which is an extension of the brain), where signals from “red” and “green” cones are compared by specialized red-green “opponent” cells.  These opponent cells compute the balance between red and green light coming from a particular part of the visual field.  Other opponent cells then compare signals from “blue” cones with the combined signals from “red” and “green” cones.  When one type of cone does not work properly, the proper color calculations cannot take place.

color deficiency
If all the cone receptors work, but one type does not work as well as the other two, an “anomalous trichromatism” results.  A weakness in the long wavelength (“red” or “L”) cones causes “protoanomaly,” where more long wavelength light is required in order to perceive colors the same as a person with normal color vision.  A weakness in the medium wavelength (“green” or “M”) cones causes “deuteranomaly,” where more medium wavelength light is required in order to perceive colors the same as a person with normal color vision.  A weakness in the short wavelength (“blue” or “S”) cones causes “tritanomaly,” where more short wavelength light is required in order to perceive colors the same as a person with normal color vision.

When one type of cone receptor does not work at all, an “anomalous dichromatism” results.  In “protanopia,” there is a lack of the receptors sensitive to long (reddish) wavelengths of light.  In “deuteranopia,” there is a lack of the receptors sensitive to medium (greenish) wavelengths of light.  In “tritanopia,” there is a lack of the receptors sensitive to short (bluish) wavelengths of light.  These conditions are portrayed as follows:

protanopia (difficulty distinguishing between blue/green and red/green)
deuteranopia (difficulty distinguishing between red/purple and green/purple)
tritanopia (difficulty distinguishing between yellow/green and blue/green)

When only one cone receptor functions, the color deficiency is “monochromatism.”  Very few people (about 3 in a million) have total “color blindness” or “achromatopsia”; they see things only in shades of white, gray and black.  Color deficiencies usually are genetic.  However, sometimes such deficiencies are acquired due to retinal diseases such as glaucoma or diabetes or by retinal poisoning by certain medications.

About 7% of males have a red-green deficiency, compared to about .4% of females.  The genes for the red and green receptors (cones) are carried on the X chromosome.  As a result, a male with a defect in one of these genes does not have another X chromosome to compensate and, therefore, will be color deficient.  On the other hand, a female with such a defective gene has another X chromosome which, as a rule, will have a compensating normal gene.  With a red-green deficiency, a person might have difficulty distinguishing between things such as red and green traffic lights or electrical wiring.  Red-green color perception is altered in conditions such as optic neuritis.

People with a less common type of deficiency cannot distinguish between blues or yellows.  The gene for the blue receptor (cone) is carried on Chromosome #7.  Blue-yellow color vision is diminished in many disorders, including glaucoma, diabetic retinopathy, cataract, and retinal disease.  In some cases, a reddish “X-chrome” contact lens, worn in one eye, can help a color deficient person discern more easily between colors.

You might wish to check your color vision.  If so, go to Color Vision Testing.

macular degeneration
Certain conditions can affect the macula and, in turn, one’s central vision.  Probably the most common is “macular degeneration,” a hereditary ocular disease.  Age-related macular degeneration (ARMD) is the leading cause of irreversible blindness among Americans 65 and older.  “Dry” macular degeneration generally is caused by a thinning of the macula’s layers, and vision loss typically is gradual.  However, tiny, fragile blood vessels can develop underneath the macula.  “Wet” macular degeneration can result when these blood vessels hemorrage, and blood and other fluid further can destroy macular tissue, even causing scarring.  In this case, vision loss can be rapid—over months or even weeks—as well as very devastating.

Macular tissue destroyed by either dry or wet macular degeneration cannot be repaired.  In the case of the wet form, a special laser can be used to seal the leaking blood vessels in the retina.  However, 1) the tiny spots where the laser burns the retina will lose vision permanently, and 2) other blood vessels may leak in the future, requiring further laser treatment.

The earliest symptom of macular degeneration usually is persistently blurred vision.  As more cells of the macula are destroyed, objects become distorted (for instance, straight lines become crooked).  Eventually, a small blind spot in the central visual field can develop and grow in size.  This can progress to the point of “doughnut” vision, where people’s faces are unrecognizable when looking directly at them, yet peripheral vision remains unaffected.

Naturally occuring carotenoids in the macula, lutein and zeaxanthin (molecular cousins of beta carotene and vitamin A), have been shown to be effective protectants against degeneration of the macula.  These pigments absorb and filter out near-to-blue ultraviolet radiation—acting essentially as built-in macular “sunglasses”—which potentially is the most damaging electromagnetic radiation reaching the macula.  Thus, the greater the amount of macular pigment, the less the risk of macular degeneration.  Lutein and zeaxanthin are found particularly in yellow fruits and in green leafy vegetables (especially xanthophyll-rich vegetables such as spinach, kale, collard greens, and broccoli), in eggs, and as nutritional supplements.

Amsler grid
A good way to detect early stages of macular degeneration (as well as some cases of cystoid macular edema or central serous retinopathy) is with an “Amsler grid.”  Two Amsler grids—one black-on-white and one white-on-black—are shown below, following these instructions:

Situate the grid so that it is as close to the center of this window frame as possible.
If you normally wear reading glasses or bifocals for near work, put them on to view the grid.
Measure (or have someone else measure) a distance of about 20 inches from your eyes to the screen.
Cover your left eye, but do not close it or press on it.
With your right eye, stare directly at the spot in the center of the grid, and do not look away from this spot.
As you notice the horizontal and vertical lines in your periphery, see if you detect any of these things:
curved lines
distorted lines
broken lines
Repeat the test with your other eye.

If you have not noticed problems with your vision, yet you detected broken, curved, or distorted lines (metamorphopsia) while using one or both of the above Amsler grids, it could be that you have an early stage of macular degeneration.  Try doing the same test later today or tomorrow.  If the results are repeatable, it probably would be a good idea to make an appointment to have your eyes examined by an optometrist, an optometric physician, or an ophthalmologist.  In any case, continue doing the Amsler grid test 2-3 times a week to monitor any changes.

cystoid macular edema (CME)
Cystoid macular edema (CME) is a painless disorder affecting the macula.  It is marked by the presence of multiple cyst-like (cystoid) formations which cause edema (swelling) in the macular area, resulting in blurred or decreased central vision.  Sometimes an eye with CME will be red and irritated, and a great deal of tearing may occur.  Also, the eye may be tender to the touch and sensitive to light.

Although the exact cause of CME is not known, it can accompany a variety of diseases such as retinal vein occlusion, uveitis, or diabetes.  It also is present after about 3% of cataract surgeries, often many months following the surgery, even if the surgery had no complications.  If CME occurs in one eye, there is up to a 50% chance that it will appear subsequently in the other eye.  Fortunately, most people recover their vision after an indefinite period of time.

To confirm the diagnosis of CME, sometimes a test known as “fluorescein angiography” is performed.  During this procedure, a fluorescent yellow dye is injected into the vein of an arm, and a series of retinal photographs are taken to show pooling of the dye in the macular area with CME (or leakage of retinal blood vessels in other conditions).

Retinal inflammation due to CME usually is treated with anti-inflammatory agents (such as Indocin or a corticosteroid) and occasionally with diuretics (such as Diamox).  It may take weeks for there to be a noticeable improvement in vision.  Sometimes, the CME is caused by vitreous strands connected to and pulling on the macula, in which a YAG laser treatment or even a vitrectomy (removal of the vitreous) is required.  Occasionally, the retinal inflammation and swelling from CME can induce a secondary glaucoma, which must be treated as a separate condition.

central serous retinopathy (CSR)
Central serous retinopathy (CSR), a painless condition which affects the central retina (macula or para-macular area), is caused by an accumulation of fluid under the retina, causing blurry vision, distortion of shapes, and sometimes a change in the refractive error (towards hyperopia).  CSR occurs when a small focal area of the retinal pigmented epithelium becomes compromised and allows serous fluid, from the chroidal vessels below, to leak underneath the retina, forming a sub-retinal blister.

The disorder affects mostly men in the age range of 20 to 50 and seems to be linked to chronic stress, whether emotional or job-related, or even with steroid use.  Some experimental evidence suggests that high blood levels of epinephrine and cortisol hormones may be indirectly responsible for some occurrences of CSR.

Most cases of CSR will resolve spontaneously in 3-6 months.  However, about 40-50% of the time, there will be recurrences of the condition.  Even without a recurrence, many people have residual symptoms after the first bout of CSR, such as distortion, decreased color and contrast sensitivity, and difficulty seeing at night.

Fluorescein angiography may be performed to determine the site of serous leakage, and laser photocoagulation may be used to shorten the duration of the disease condition.  However, laser treatment may produce a noticeable, permanent blind spot and most likely will not decrease the chances of a recurrence.

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