ITCHING EYE :Itching is the hallmark sign of SAC or PAC. Your patients' eyelids are swollen, and their eyes are red, chemotic and watery. Scrapings show elevated eosinophils. Whether the problem is seasonal (pollens) or perennial (dust mites, animal dander and mold), your patients' allergies are causing ocular surface inflammation and maddening discomfort.

Ocular allergies result in swollen eyelids and red, chemotic watery eyes.

Allergies cause mast cell degranulation and the release of histamines and proinflammatory mediators. Therefore, the most effective medications will address both problems.

The allergic reaction is triggered by antigens, which cross-link with the immunoglobulin E antibody (IgE) on the mast cells, leading to mast cell degranulation. This, in turn, releases histamines and proinflammatory mediators, such as prostaglandins, tryptase and heparin. The histamine quickly binds with H1 receptor sites on the nerves and causes itching. It also binds to H1 receptor sites on the blood vessels, causing redness, chemosis and fluid leakage. The proinflammatory mediators only add to the redness and swelling, and there's no end in sight, because antigens continue to bombard the eyes as part of the inflammatory cascade.

Dual effects

If we follow the etiology of allergic conjunctivitis, we can discern some important information. With 50 million mast cells in the human conjunctiva, the mast cell is central to the ocular allergic response. Allergies cause mast cell degranulation and the release of histamines and proinflammatory mediators. Therefore, the most effective medications will address both problems and will rapidly relieve symptoms.

Antigens that cross-link with the IgE antibody on the mast cells trigger the allergic response. This leads to mast cell degranulation and the release of histamines and proinflammatory mediators.

An antihistamine's mechanism of action is simple. It's attracted to the same H1 receptor sites that histamine seeks. It binds to those sites, effectively blocking the attachment of histamines and preventing itching and redness. Clearly, it's beneficial to put an antihistamine to work early in the inflammatory process.

We also need to use a mast cell stabilizer to effectively treat ocular allergy. These drugs prevent recurrence of the allergic response by inhibiting the release of proinflammatory mediators.

Study results

The most commonly prescribed drugs for ocular allergies are olopatadine 0.1% (Patanol, Alcon), olopatadine 0.2% (Pataday, Alcon), epinastine (Elestat, Allergan), ketotifen fumarate (Zaditor, Novartis Ophthalmics) and azelastine (Optivar, Meda Pharmaceuticals Inc.).

Olopatadine 0.1% is the market leader because studies have shown it's clinically effective as a specific H1 antagonist and mast cell stabilizer. It has a quick onset of action, and it's been shown to be comfortable and safe for patients.^1–11

In a conjunctival allergen challenge (CAC) study, which compared olopatadine 0.1% to azelastine⁵ and epinastine¹¹, mean itching scores at 5 minutes were better for olopatadine with statistical significance. The drug also performed better in ocular redness at onset and 10, 15 and 20 minutes post-challenge. Another study showed that olopatadine was significantly more comfortable in the eye than azelastine.⁶

While results are satisfying, another factor has driven the development of another olopatadine formulation: olopatadine 0.2%. Some studies show overall improvements in adherence, patient quality of life, patient satisfaction and cost when patients can dose less frequently.¹² What's more, 95% of allergy patients say that a long-lasting allergy medication is important, so they may be more satisfied if they can use fewer drops.¹³

A once-a-day drug like olopatadine 0.2% could improve compliance over olopatadine 0.1%, and increased compliance through daily dosing has been shown to give patients better symptom control.¹² In an in vitro animal comparison of the two concentrations, olopatadine 0.1% lasted 14 to 15 hours, compared to 24 hours for olopatadine 0.2%.¹⁴

Newest option

Indicated for the treatment of ocular itching associated with allergic conjunctivitis, olopatadine 0.2% has the same safety profile as olopatadine 0.1%. Olopatadine 0.2% has an increased concentration and longer duration, which is why patients need to use it only once a day.^15,16

An antihistamine is attracted to the same H1 receptor sites that histamine seeks. It binds to those sites, effectively blocking the attachment of histamines, thereby preventing ocular itching and redness.

During in vitro studies, both doses of olopatadine thwarted the biphasic process that degranulates mast cells and releases mediators, while epinastine, azelastine and ketotifen did not.^17,18

In more than 10 clinical trials, more than 1,000 patients have been exposed to olopatadine 0.2%. In a randomized, double-masked, placebo-controlled CAC trial¹⁹ that studied 45 people with a history of allergic conjunctivitis, researchers checked patients for itching and redness at onset and after 24 hours. They found that olopatadine 0.2% significantly reduced ocular itching compared to placebo. In the same study, researchers also found a beneficial effect on conjunctival redness.

A multicenter, 10-week study²⁰ looked at the efficacy of olopatadine 0.2% against itching in 260 patients who were sensitive to grass pollen and experienced redness and tearing. They received 1 drop in each eye, once a day. In weekly assessments, patients rated olopatadine 0.2% significantly better than placebo in itching frequency. What's more, the results improved over time as the mast cell stabilizer had time to take effect. Ocular redness fared better than placebo in the same 10-week period.

In addition, the environmental study showed that 0.2% olopatadine was effective, even as allergen levels fluctuated from low to moderate.²⁰

In comparative drug studies, olopatadine 0.2% has continued to fare well. In the double-blind CAC trial²¹ against epinastine, 92 patients underwent screening, confirmation and an office visit.

Results showed that olopatadine 0.2% reduced itching and redness more effectively than epinastine and also scored well in the comfort comparison index.

Indicated for the treatment of ocular itching associated with allergic conjunctivitis, olopatadine 0.2% has the same safety profile as olopatadine 0.1%, [but offers] an increased concentration and longer duration.

                         Strabismus

Strabismus, more commonly known as cross-eyed or wall-eyed, is an eye muscle condition in which one or both eyes may turn in (esotropia), out (exotropia), up (hypertropia) or down (hypotropia).

The eyes are not properly aligned and do not focus on an object together at the same time. One eye may be turned all of the time or only some of the time. Most people who have strabismus are usually born with it or develop it at an early age. However, some forms of strabismus occur later in life.

Symptoms:

Newborns often have crossed eyes to some degree due to underdeveloped vision, but this usually disappears by the age of 3 to 4 months. True strabismus does not disappear as the child grows. If you think your child is showing signs of true strabismus, it is important to seek the advice of an eye care professional. The earlier the detection and treatment, the better the child's vision will be. Symptoms to watch out for include:

• Eyes that appear crossed
• Eyes that do not align in the same direction
• Eyes that do not move together
• Double vision
• Vision in only one eye, with loss of depth perception

Causes:

Strabismus is caused by a weak eye muscle or a weak signal from the nerve that controls the eye muscle. Frequently, uncorrected farsightedness and focusing problems are the underlying causes of strabismus in children. Some children are born with a defective visual processing center in the brain. Strabismus may also develop if a child is born with a cataract. It is common in conditions such as Down’s syndrome and cerebral palsy. Bleeding in the brain, a brain tumor, nervous system disorders, diabetes, high blood pressure, myasthenia gravis, thyroid disease and severe vision loss can also cause strabismus.

Risk factors:

One of the highest risk factors for strabismus is having a family history of strabismus. Having a moderate to high amount of farsightedness at a young age can also increase the risk significantly, as does having a disease such as diabetes or high blood pressure. In addition, strabismus may develop as a complication of any other disease causing vision loss.

Types:

Strabismus is categorized as being either constant (turned in all of the time) or intermittent (turned in some of the time). Cases of crossed-eyes, or esotropia, are classified as either "congenital" or "accommodative" esotropia.

• Congenital esotropia: An uncommon condition in which a baby is born with an inward turn of a large amount, usually appearing between the ages of 2 and 4 months.
• Accommodative esotropia: An inward turning eye that occurs because the eye is attempting to compensate for uncorrected farsightedness or a focusing disorder.

• Diagnosis:

  Besides parents, a pediatrician or family doctor is often the first person to detect strabismus. A baby whose eyes do not appear straight by the age of 3 to 4 months should be examined. To properly diagnose strabismus, a complete eye examination must be performed by an eye doctor. Early diagnosis is very important, as some eye turns may be a result of a serious medical condition. Strabismus that is not treated early in a child’s life may cause amblyopia (lazy eye), a condition in which vision develops poorly. In addition, the cosmetic appearance of strabismus may cause a lack of self-esteem.

  Treatment:

  Strabismus cannot be outgrown. Treatment to straighten the eyes is required. Treatment will depend on the type of strabismus and its cause:

  • Glasses may be prescribed to improve focusing and enable the eyes to straighten.
  • Patching the good eye will force a patient to use the affected eye. Patching will improve the chances of normal vision to develop.
  • Eye drops may be used to blur the good eye, forcing the affected eye to be used. (This achieves the same result as patching.)
  • Eye muscle surgery may be an option if non-surgical treatments do not work.
  • Some eye doctors may prescribe eye exercises before or after surgery.
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  •                   Albinism  Child's Eyes

    If your child has just been diagnosed with albinism, you may be wondering how the condition might affect his eyes and vision. Albinism is an inherited disease that can affect both the eyes and the skin, but sometimes it only affects the eyes. People with albinism typically have little to no pigment in their skin and hair.

    Albinism can sometimes have profound effects on vision and eye health. The disease can affect the amount of pigment present in the back of the eye as well as the development of the neural connections between the eyes and the brain, causing problems such asnearsightedness, astigmatism, light sensitivity, and glare. Fortunately, eyeglasses may significantly improve your child's overall eye problems.

    Albinism and Eye Color

    Children with albinism usually have blue eyes, but some have brownish-colored eyes. Some children will even appear to have pink or red eyes, because the iris doesn't contain much pigment. The pinkish color results due to a lack of pigment in the iris. The inside of the eye will also appear very light because the eyes lack the pigment that is contained in the layer directly beneath the retina.
    

    Albinism and Refractive Errors

    Children with albinism tend to be nearsighted or farsighted and often have large amounts of astigmatism. Glasses or contact lenses can be used to correct these vision problems.

    Albinism and Light Sensitivity

    Children with albinism can have profound light sensitivity. In a normal eye, the iris helps to shield the retina from bright light. When a child has albinism, their iris is sometimes so light in color that it can't properly control the amount of light that hits the retina. Also, because the back of the eye also lacks pigment, light is not absorbed properly and scatters, creating more light sensitivity. These children require sun protection, including quality sunglasses or tinted contact lenses.

    Some children with albinism may benefit from a permanent tint in their prescription eyeglasses that is light enough to function indoors. Children with albinism may also benefit fromphotochromic lenses. Photochromic lenses darken to a grey or brown shade when in sunlight and automatically lighten back to clear indoors. Many different types of photochromic lenses are available today and they may benefit from photochromic lenses that turn darker outside but do not necessarily lighten up completely when indoors. They remain slightly tinted indoors.

    Albinism and Glare

    Glare is light that is reflected off surfaces such as water, waxed floors and white sand. Glare can make even the cloudiest day uncomfortable for children with albinism. Because glare can be debilitating to these children, polarized sunglass lenses are highly recommended. Polarized sunglasses reduce not only the amount of light that enters the eye but they also virtually eliminate associated glare. Polarized lenses can make children with albinism much more comfortable and deliver a much better visual experience for them. Polarized lenses are available in many different colors and are available in both constant tints and photochromic options.

    To further enhance comfort for children with albinism, many doctors and opticians recommend adding a mirror coating to their sunglass lenses. A mirror coating will reduce the amount of light that reaches the eyes even further and deflect the light that bounces up and enters the eye from below.

    Albinism and Other Vision Problems

    Children with albinism may also develop other vision problems that will require attention, such as nystagmus and strabismus. Nystagmus is an involuntary flicker of the eyes. Nystagmus usually causes a child to make quick, jittery movements by both eyes. Strabismus is an eye muscle condition that causes one or both eyes to turn in, out, up or down.
    

               Vision Screening for Kids

    
    

    An evaluation of your child's eyes should occur at all well child visits, even as an infant.

    Routine vision screening is important, because many abnormalities are treatable if discovered early, and untreated, can lead to vision loss and blindness. Among the vision problems that your Pediatrician will evaluate your child for include:

    • strabismus - a misalignment of the two eyes, affecting about 4% of children. Strabismus is usually described by the direction of misalignment, which can be outward (exotropia), inward (esotropia), upward (hypertropia) or downward (hyotropia). A child may also have a phoria, with eye deviation only when one of the eyes is covered or when he is tired or sick.
    • amblyopia - reduced vision in an eye, which can be secondary to strabismus, anisometropia (unequal refractive errors in both eyes, for example, if one eye is more farsighted than the other eye), congenital cataracts, etc.
    • refractive errors - such as myopia (nearsightedness) and hypermetropia (farsightedness).

    In younger children, a vision evaluation will usually consist of an examination for the red reflex (checks for cataracts and retinoblastoma), eye alignment (misaligned eyes may indicate strabismus) and eye movements. Older children, beginning at three years of age, should have a more formal test of their vision. Until formal vision testing is possible after three years of age, younger children's vision can be assessed by observation of how they fixate and track objects and by the history of the child's parents. Visual milestones for infants include being able to follow an object to midline in the first 2-6 weeks, past midline by 1-3 months, and follow an object 180 degrees by 3-5 months. If your child isn't meeting these developmental milestones on time, then you should see your Pediatrician for an evaluation.

    
    

    Other testing may include the corneal light reflex test, in which a light is directed at the bridge of the nose and the light reflex is examined to make sure it is symmetrical or shines in the same spot on both eyes. If the light reflex is off-center or not symmetrical in both eyes, then it might indicate a misalignment of the eyes. This is useful to differentiate pseudostrabismus, a condition in which the eyes appear to be misaligned because of prominent epicanthal folds or a broad nasal bridge and which doesn't require treatment, from true strabismus.

    The unilateral cover test can be used to determine if an infant or young child will follow an object while one of the eyes is covered. For example, your Pediatrician can see if your child can fix on and follow a toy with both eyes, and then cover the left eye and see if he continues to follow it with his right eye. Then, the right eye is covered to see if he will follow the toy with his left eye. If he gets really fussy or refuses to follow the object when you cover one of his eyes, then that may indicate that the vision in the other eye is reduced.

    In older children, the unilateral cover test is also useful to check for strabismus. While the child is looking at a distant object, such as an eye chart or toy, cover one of his eyes. If the other eye moves outward or inward, then that might indicate that his eyes are misaligned and that he has strabismus. The test is then repeated by covering the other eye.

    Other problems that indicates the need for further evaluation include parents noticing that their child's eyes are crossing, that their eyes aren't straight or if they just don't seem to be seeing well. It is important to keep in mind that younger children usually don't report problems with their vision, especially if the problem is in just one eye and the other eye is accomodating for it. Older, school age children, may report that they can't see the board, or they may have frequent headaches, double vision or are frequently squinting. Formal testing of visual acuity is usually possible once a child is three years old, although 2 year olds may be able to be tested with picture cards

    
    

    
    

Dr.kalpana.

infection

Herpes simplex virus (HSV) is the most common infectious cause of corneal blindness in the Western Hemisphere, with up to 500,000 cases diagnosed annually in the United States alone. HSV is a multifaceted disease capable of inducing some of the most difficult management problems, including neurotrophic keratopathy. Herpetic neurotrophic keratopathy often presents with decreased corneal sensation and significantly impairs the ability of the corneal epithelium to heal itself after corneal injuries, leading to corneal ulcers in the absence of active virus. Neurotrophic keratopathy can also develop after Herpes Zoster (shingles) which leads to chronic epithelial disease and loss of vision. The persistence of decreased corneal sensation and its association with the degree of nerve damage in the cornea are still unknown.
In collaboration with Dr.Kalpana professor  of Ocular Virology, we are currently studying the nerve changes and cellular changes in herpetic disease. Through the use of the new state of the art HRT/RCM confocal microscope, which allows a revolutionary layer-by-layer analysis of the cornea and a magnification of up to 800 times, we are able to perform non-invasive examination of the cornea and obtain images of corneal layers and cells.

Treating the Ocular Component of Allergic Rhinoconjunctivitis and Related Eye Disorders:

D.RAJESH DODDAA range of treatment options are available for the control of ocular allergy symptoms, some of which may obviate pharmacologic interventions . Allergen avoidance is implemented by minimizing patient contact with the allergens to which they are sensitive; however, the eyes present a large surface area and thus it is often impossible or at least impractical to avoid ocular exposure to airborne allergens. Allergens can also be diluted and removed from the ocular surface through lubrication with artificial tears (saline combined with a wetting and viscosity agent); however, the unit-dose packaging required for sterility makes these products expensive, and they do not treat the underlying allergic response. Cold compresses are another nonpharmacologic intervention that may provide relief from ocular symptoms.

When avoidance and nonpharmacologic strategies do not provide adequate symptom relief, pharmacologic treatments may be applied topically or given systemically to diminish the allergic response. For example, the H ₁ topical antihistamine levocabastine hydrochloride is effective in rapidly relieving ocular inflammation when administered topically to the eye.  However, a limited duration of action necessitates frequent dosing of up to 4 times per day,  and topical antihistamines may be irritating to the eye, especially with prolonged use. Because atopy has been shown to be related to a fivefold increase in symptoms during allergy seasons, patients who use contact lenses should consider the use of soft daily-disposable lenses for comfort.  A small percentage of patients may have to discontinue the use of contact lenses during acute periods.

Combination treatments using decongestants with antihistamines have been shown to be more effective, and are administered to the eye as drops up to 4 times daily. Decongestants (oxymetazoline hydrochloride, tetrahydrozoline hydrochloride, and naphazoline hydrochloride) act primarily as vasoconstrictors and are effective in reducing erythema  ; however, adverse effects include burning and stinging on instillation, mydriasis, and rebound hyperemia or conjunctivitis medicamentosa with chronic use. Therefore, these treatments are suitable only for short-term symptom relief, and are not recommended for use in narrow-angle glaucoma patients.

Mast-cell stabilizing medications (cromolyn sodium 2% or 4%, lodoxamide tromethamine 0.1%, nedocromil sodium 2%) can also be applied topically to the eye, and may be suitable for more severe forms of conjunctivitis. However, for mast-cell stabilizers to be effective, the mast cell has to be de-activated before the allergic reaction is triggered, thus they require a loading period during which they must be applied before the antigen exposure. Compliance is, therefore, an important factor because frequent regular dosing before an allergic reaction can become difficult for patients to adhere to. Cromolyn sodium is used in several types of conjunctivitis, including forms of AC; however, studies have shown only marginal effectiveness compared with placebo.  Lodoxamide tromethamine is more potent than cromolyn sodium in the prevention of histamine release in animal models,  and has been shown to provide relief from the symptoms of VKC. Nedocromil sodium has also been shown to be more potent than cromolyn sodium. 

In contrast to classical mast-cell stabilizers, the topical antihistamine mast-cell stabilizers have a dual mode of action: they inhibit mast-cell degranulation while competitively blocking histamine binding to H ₁receptors, thus providing rapid allergic symptom relief through antihistamine action. As a result of this more rapid action, compliance is likely to be greater compared with that of the pure mast-cell stabilizers. Topical nonsteroidal anti-inflammatory drugs (NSAIDs) are possible candidates for treating the symptoms of SAC. The only NSAID currently approved for SAC is ketorolac tromethamine 0.5%, which works on the arachidonic acid cascade and is effective in reducing ocular itching. However, as is the case for several classes of topical ocular treatments, NSAIDs are also known to cause discomfort on instillation,  which may affect patient compliance.

The more severe variants of conjunctivitis, including AKC, VKC, and GPC, can be controlled by topical corticosteroids (loteprednol etabonate 0.2% and rimexolone 0.1%), which are also effective in the treatment of acute and chronic forms of AC. . Corticosteroids administered via eye drops are associated with serious adverse events when administered over long periods, including increased intraocular pressure (IOP) and cataract formation, and these agents are therefore appropriate for short courses (up to 2 weeks); however, if needed for longer durations, an eye examination should be carried out, including baseline assessment of cataracts and IOP. 

The topical ocular treatments described above share common limitations that arise from the mode of administration. Many adults have poor tolerance of eye drops, and they are particularly difficult to administer in a sterile manner when patients suffer from arthritis or tremors, or when used in pediatric practice. Since eye drops are cleared rapidly from the eye, efficacy and duration of action may be reduced, necessitating frequent administration and increasing expense. Moreover, compliance is a major issue in the use of eye drops,  which may be exacerbated by allergies that affect multiple systems. Patients may need to use a nasal treatment plus oral antihistamines, and topical creams and inhalers. It may be beneficial to reduce the number of agents used regularly by a patient through the use of immunotherapy, and orally or nasally administered allergy treatments that are effective against ocular symptoms. 

The efficacy of immunotherapy against ocular symptoms precipitated by conjunctival antigen challenges was originally demonstrated in 1911,  and this well-established method may be considered for the long-term control of AC. Although some more recent studies have focused on nasal rather than ocular symptoms,  others have confirmed the efficacy of immunotherapy against ocular symptoms. However, immune responses to allergen administration are not predictive of the effectiveness of the therapy,  and the therapy itself can produce systemic reactions, the incidence and severity of which vary dependent on the type of allergen administered.  Traditionally, immunotherapy has involved subcutaneous administration of allergen solution; however, newer sublingual immunotherapy (SLIT) provides a more convenient option. SLIT requires further evaluation for ocular allergy relief; it has been shown to control ocular signs and s ocular symptoms may respond less well than nasal symptoms. 

Oral antihistamines (cetirizine hydrochloride, desloratadine, fexofenadine hydrochloride, and loratadine) are commonly used for the therapy of nasal and ocular allergy symptoms. These newer second-generation antihistamines are recommended in preference to first-generation antihistamines because they have a reduced propensity for adverse effects such as somnolence.  Loratadine has been shown to have a protective effect in conjunctival provocation tests,  and desloratadine and fexofenadine hydrochloride have been found to significantly reduce ocular symptoms of SAR in placebo-controlled studies. In addition, cetirizine has demonstrated efficacy against symptoms of AC in conjunctival provocation tests;  however, a double-blind placebo-controlled trial showed no impact on ocular symptoms of perennial allergic rhinitis (PAR).  Second-generation antihistamines can, however, induce ocular drying,  which may impair the protective barrier provided by the ocular tear film and thus actually worsen allergic symptoms. It has therefore been suggested that the concomitant use of an eye drop may treat ocular allergic symptoms more effectively.  Indeed, ketotifen fumarate plus desloratadine,  and olopatadine hydrochloride plus loratadine have been shown to be more effective than either antihistamine alone as a result of the local effect of the topically applied agent. In addition, one trial has shown that eye irritation was significantly reduced by an antihistamine preparation that had been formulated for intranasal application (azelastine hydrochloride).  However, these results have been inconsistent because eye watering was significantly reduced compared with placebo by twice-daily (but not once-daily) application of azelastine hydrochloride in 1 trial,  but was not significantly reduced in another. 

Intranasal corticosteroids (INS) are highly effective for treating nasal symptoms of AR,  but the evidence that they may also be effective for the treatment of ocular symptoms is inconsistent. Currently, the mechanism by which intranasal treatments act on ocular symptoms is not known. Potential mechanisms include improved drainage of ocular secretions resulting from a reduction of edema and inflammation around the lower end of the nasolacrimal duct, and a decrease in neuronal reflex activity. It is well established that allergen challenges to one side of the nasal cavity lead to nasal secretion in the contralateral cavity via a neurologic reflex. Nasal challenges have also produced ocular itching in 90% of patients in 1 study,  and ocular symptoms in approximately 20% in another, suggesting that ocular symptoms may be induced by a nasal-ocular reflex . It may be the case that INS inhibit the nasal-ocular component of ocular allergy symptoms, but not the direct ocular component.

The variation in effectiveness of INS on ocular symptoms may therefore be the result of varying levels of affinity for nasal receptors. Systemic effects are unlikely with these agents as they have low bioavailability and rapid first-pass metabolism leading to low plasma levels.  Thus, the amount of an intranasal steroid available in the eye for a direct therapeutic effect is miniscule. Passage of agents from the nose to the eye via the nasolacrimal duct has also been shown to be unlikely.  A number of large clinical trials have investigated the ocular efficacy of INS in allergic patients; a meta-analysis of 16 randomized controlled trials showed that INS were more effective against several nasal symptoms of AR than oral antihistamines, and also found no difference in efficacy against AR ocular symptoms between the treatment classes.  Similar conclusions were drawn by a systematic review that determined that 9 of 10 AR studies showed no difference in efficacy for ocular symptoms between INS and oral antihistamines, while 1 study showed superiority of the oral antihistamine.  In contrast, pooled efficacy data from 7 multicenter, randomized, double-blind, placebo-controlled studies have shown that the INS fluticasone propionate 200 mcg once daily provides effective relief of ocular symptoms associated with SAR.  In accordance, a randomized, double-blind, parallel group study conducted at 14 investigative sites showed that fluticasone propionate 200 mcg once daily significantly decreased the ocular symptoms score compared with vehicle placebo however, other placebo-controlled trials found no effect of fluticasone propionate on eye symptoms in adults  or children  with SAC.

Another nasally administered corticosteroid, triamcinolone acetonide, has also been shown to have efficacy against ocular symptoms; however, only 1 placebo-controlled trial showed a statistically significant improvement, and these findings have not been consistent.  Similarly, a pooled analysis of 4 studies found that mometasone furoate 200 mcg once daily may also provide relief from ocular symptoms in patients with SAR. In a recent study, ciclesonide did not have a significant effect on non-nasal symptoms, or the eye symptom domain of the RQLQ.

Ocular allergies, which are often underdiagnosed, have a significant impact on the life of the patient. These symptoms are expensive in terms of treatment and also in terms of indirect costs. It is vital to reach a better understanding of allergic mechanisms and inflammation, which may lead to improved treatment. Moreover, the emergence of new medications for the treatment of nasal and ocular symptoms may improve compliance in patients suffering from allergic conditions, such as AR, in which the ocular component is present. Currently, the most effective treatments for AR are INS; it would be advantageous, therefore, to develop a drug of this class that is consistently shown to improve eye symptoms (as well as nasal symptoms) to provide greater symptom relief, increase patient compliance, and reduce costs associated with the current requirement for multiple medications.

D.RAJESH 

CorneaCorneal Transplal CORNEAL                TRANSPLANTATIONnsp

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TRANSPLANT SURGERY…WHAT TO EXPECT:   Although only 20-25% of those with Keratoconus ultimately require corneal transplant surgery, for those who do, it is a crucial and sometimes worrisome decision. However, those who know what to expect before, during, and after surgery are better prepared and feel more in control of their eye care.     In Keratoconus, a corneal transplant is warranted when the cornea becomes unacceptably thin or when sufficient visual acuity to meet the individual's needs can no longer be achieved by contact lenses due to steepening of the cornea, scarring or lens intolerance. Lens intolerance occurs when the steepened, irregular cornea can no longer be fitted with a contact lens, or the patient cannot tolerate the lens.     Once the decision has been made, you will feel less anxious and more in control if you know what to expect and what the “normal” routine is for this type of surgery. The more information you have, the more prepared you will be.     It is a good idea to check with your insurance company prior to scheduling your surgery to check your coverage and any pre-authorization requirements. Ask specially about your post operative office visits, medicines, glasses and/or contact lenses.     A few days prior to surgery a general medical examination and routine laboratory tests (such as blood count and EKG) are done to ensure that you are fit enough to undergo surgery. You should not use aspirin for 2 weeks prior to surgery, since it tends to cause bleeding during surgery. Antibiotic drops are generally started one day before surgery to protect the eye from infection.     Do not eat or drink anything after midnight before the surgery (ask your doctor about taking prescribed medications on the day of the surgery). In most cases, the surgery is done on an outpatient basis - you enter the hospital or surgery center a few hours prior to surgery and leave the same day- generally a few hours after the surgery. In the “pre-op” waiting area, you might be “prepped”- medication will be given to help you relax before surgery. A needle attached to tubing will be inserted to deliver fluids and medications into your vein and EKG leads will be attached to your chest in order to monitor your heart. These are standard safety precautions.     Local or general anesthesia can be used for this procedure. The decision as to which type is used should be discussed with your surgeon preoperatively and is based on your age, general health, length of surgery, your doctor's preference and your anxiety level.     In the operating room, your eyelids are carefully washed and covered with a sterile plastic drape. Oxygen is occasionally provided by a plastic tube placed near the nose. Patients often doze off during the operation, and most are left with vague recollections of a short procedure, although some remember all of it.     The entire procedure is done under a microscope. A circular cookie cutter-like instrument, called a trephine, is used to remove the center of the diseased cornea. A "button" is cut from the donor cornea. This donor tissue is then sewn in place with extremely fine nylon sutures.     At the conclusion of the procedure, a patch and shield are applied to protect the eye. You will then be taken to the recovery room , in case of general anaesthesia, to wait until you are fully awake before being discharged.     After surgery, you should rest the remainder of the day. Post surgical pain varies from person to person. Typically there is either no pain or only slight soreness for a few days which is usually relieved by painkillers. Discuss pain management with your surgeon before and after the surgery.     The eye drops are very important- be sure you know exactly when you should use them. Make your next appointment, usually in three to seven days. Be sure you know how to contact the doctor if there is a problem or you have any questions.     After the patch is removed, it is important to protect the eye from accidental bumps or pokes. Typically, for several months after surgery, patients wear glasses during the day and a plastic shield at night to protect the eye from trauma while sleeping. Since the new cornea is delicately sutured in place, a direct blow to the eye must be avoided. Contact sports are discouraged after corneal transplant. Otherwise, normal activity can be resumed within a few days. After the first day, shaving, brushing teeth, bathing, light housework, bending over, walking, reading, and watching TV will not hurt the eye.     Because the cornea has no blood supply, the transplant heals relatively slowly. Sutures are left in place for three months to one year, and in some cases if the vision is good, they are left in permanently. The sutures are buried and therefore don't cause discomfort. Occasionally, they do break and then need to be removed. Often they are removed, adjusted or loosened to improve vision. Suture adjustment and removal are simple, painless office procedures.     The sutures used in corneal transplants are made of a monofilament nylon and are quite small (22 microns - 1/3 the thickness of a human hair). There are many different suturing patterns used by surgeons the world over. All of these suture techniques are effective. Some are utilized because of the surgeon's preference and training. Other suturing techniques are employed depending on the specific problem for which the transplant is being done. In some cases, surgeons will use 16 individual ("interrupted") sutures; others use a continuous ("running") suture, which is much like a hemstitch. Still others routinely use a combination of both types. In all cases, the results are more or less equivalent.     Vision gradually improves as the new cornea heals. There is often useful vision within a few weeks. However, in some cases, it may take several months to a year for good visual acuity.     To prevent rejection of the new cornea, steroid eye drops are used for several months after surgery. In some cases, low dosage steroid drops are continued indefinitely. Unlike oral steroids, steroid eye drops cause no side effects elsewhere in the body. Occasionally, other eye medications are necessary.     It is important to call immediately (including weekends, evenings, and holidays) if you notice any unusual symptoms, including Redness, Sensitivity to lights, Vision loss, or Pain ("RSVP"). Flashing lights, floaters, and loss of peripheral vision should also be reported immediately.     Postoperative care is extremely important and by far the most time-consuming part of having a corneal transplant. The eye is checked the day after surgery, several times in the first two weeks, at gradually longer intervals over the first year, and usually yearly thereafter.   There is every reason to believe your graft will succeed and last a lifetime. With proper care and prompt attention to any signs of rejection the graft will remain clear and healthy. Vision after a Corneal Transplant:   Vision varies a great deal after a transplant and continues to change for many months. It may start out very poor and gradually improve or be very good immediately after surgery and then worsen. It could take up to a year to develop good, stable vision. The more severe the keratoconus is, the more likely it is to see a dramatic improvement immediately after surgery. This is due to the dramatic change that occurs when the bulging and distorted cone is replaced with a new smooth donor graft. While some patients develop good vision while the sutures are still in place, best, most stable vision usually occurs after all the sutures are removed. Suture removal occurs at different times for different patients. It depends on the rate of healing, which is faster in younger people. The majority of keratoconus patients have their sutures removed 6-12 months after surgery. An important question is the level of uncorrected vision that can be expected after surgery. Will glasses be an option, or will contact lenses still be needed? A small percentage of transplant patients do obtain uncorrected vision good enough that neither glasses nor contacts are needed after surgery, but in the majority of cases, some form of vision correction is needed after surgery. Although vision may not be perfect after surgery, it is nearly always a lot better than it was before. Our consultants have considerable expertise in various lamellar surgeries like DSEK, DSAEK, DALK etc. DSEK (Descemet Stripping Endothelial Keratoplasty) and DSAEK (Descemet Stripping Automated Endothelial Keratoplasty) refers to a partial thickness corneal transplantation in which a small amount of stroma( a layer of the cornea) and the endothelium( the innermost part of the cornea) is transplanted to a decompensated cornea. DSEK/DSAEK is performed for corneal diseases like Fuch’s endothelial dystrophy, pseudophakic/aphakic corneal edema (corneal decompensation following cataract surgery) and any disorder in which the endothelium is dysfunctional. Advantages of DSEK are manifold, making this the procedure of choice wherever indicated. The main advantage is the lack of sutures (used in traditional penetrating keratoplasty). Also, following DSEK, the visual recovery is more rapid and astigmatism (irregular shape of the cornea) is lesser. DALK (Deep Anterior Lamellar Keratoplasty) refers to transplantation of only the top and middle layers of the cornea, leaving the innermost layer (endothelium) of the patient intact. The main advantages of this procedure is minimal/ nil chances of corneal endothelial rejection. DALK is increasingly being performed for keratoconus, other corneal diseases (scars) involving the top and middle portions of the cornea. FEK ( Femtosecond laser Enabled Keratoplasty)  - The newest approach to corneal transplantation uses a femtosecond laser  - the same technology used for making flaps in LASIK surgery – to produce incisions in the cornea that enable the surgeon to exercise far more precision in what is removed, so that the transplanted tissue fits into the cornea like interlocking pieces of a puzzle. This dramatically reduces postoperative astigmatism because of the precision of the laser, and it strengthens the wound site, so that it is more resistant to traumatic opening in the event of eye injury following surgery. The cornea surgeon would examine your cornea and suggest the surgical procedure of choice, that would be the best option in your case scenario. The news is also good for patients with diseased cornea who are not candidates for transplantation using donor tissue. Instead, some of these patients may be candidates for an artificial cornea transplant.

COLLAGEN CROSS LINKING

What is collagen cross-linking?   Although many current treatments can improve vision in keratoconus, they do not treat the underlying cause of the corneal weakness and distortion i.e they do not stop the progression of keratoconus. Collagen cross linking with riboflavin (commonly known as C3R) is one such treatment modality which stops propressive weakening of the cornea that occurs in keratoconus. The one hour C3-R treatment is performed in the hospital. During the treatment, custom-made riboflavin eye drops are applied to the cornea, which is then activated by ultraviolet A  light(370nm). This amazingly simple process has been shown in laboratory and clinical studies to increase the amount of collagen cross-linking in the cornea and strengthen the cornea. In published European studies, such treatments were proven safe and effective in patients. A pilot clinical study in humans evaluated the effect of the new cross-linking method in patients with keratoconus and showed that, in all treated eyes, progression of the condition was halted. To date there are over 700 patients with more than 5 years follow-up after cross-linking treatment and some eyes have been followed for 7 years with encouraging results.   How is the treatment done?   The treatment involves removing the superficial layer (epithelium) from the surface of the cornea and then applying Riboflavin eye drops to the eye for 30 minutes. The eye is then exposed to UVA light for another 30 minutes. After the treatment, a bandage contact lens is worn for 1-3 days until the surface of the eye has healed. Antibiotic and steroid eye drops are also prescribed for  a few weeks.   Who can benefit from this treatment?   It is important to understand that collagen cross-linking treatment is not a cure for keratoconus. Rather, it aims to slow or even halt the progression of the condition. After the treatment, it is expected that it will continue to be necessary to wear spectacles or contact lenses (although a change in the prescription may be required). However, it is hoped that the treatment will prevent further deterioration in vision and the need for corneal transplantation. Thus initially the treatment would be offered only to patients in whom there is clear evidence of progression of their keratoconus. A person whose keratoconus is already so bad that it cannot be corrected by contact lenses is unlikely to gain any benefit from this treatment. In this situation a corneal transplant is usually required.  What are the risks?   There are a number of potential risks associated with this treatment although very few complications have been reported so far. Ultraviolet light is potentially harmful to the eye .However, the dose used is designed to prevent observable damage to the sensitive cells that line the back of the cornea (endothelium) or the other delicate structures within the eye eg lens and retina. No lens opacities (cataracts) have been attributed to this treatment in European trials. The treatment involves the scraping away of the outer layer (skin or epithelium) of the cornea. There is therefore a risk that the surface of the cornea will be slow to heal. Infection may occur which could lead to the development of corneal scarring. Antibiotics are routinely used to prevent this complication. Corneal scarring might necessitate further surgical procedures (including corneal transplantation)though this is extremely rare. Other lesser but more common risks include:     Inability to wear contact lenses for several weeks after the treatment.     Changes in the shape of the cornea necessitating a refitting of a contact lens or a change in the spectacle correction.     As is the case with any experimental treatment, there may also be long-term risks that have not yet been identified.     The increased corneal rigidity induced by exposure to UVA and riboflavin may wear off over time and further periodic treatments may be required, raising the possibility of other side effects from repeat doses of the treatment.

Intacs for Keratoconus INTACS is the trademark name for micro-thin prescription inserts which were previously used as a form of refractive surgery in the treatment of low levels of myopia or nearsightedness, but have recently received FDA approval for keratoconus. Narayana Nethralaya was the first hospital to introduce INTACS in the country in 2005. INTACS are thin plastic, semi-circular rings inserted into the middle layers of the cornea. When inserted in the keratoconus cornea they flatten the cornea, changing the shape and location of the cone. The placement of INTACS remodels and reinforces the cornea, eliminating some or all of the irregularities caused by keratoconus in order to provide improved vision. Though INTACS can often improve uncorrected vision, however, depending on the severity of the keratoconus, glasses or contact lenses may still be needed for achieving the best possible functional vision.

What are the advantages of the Intacs procedure as compared to a corneal transplant?
A corneal transplant is an invasive surgical procedure, requiring the removal of a section of your cornea and having it replaced with donor tissue. Although successful, it is a delicate procedure with typically a long recovery period. The INTACS procedure does not require removal of corneal tissue, but rather works on the principle of reshaping your own cornea from within utilizing special designed corneal inserts that provide structure to a weakened cornea. The recovery period is typically short, with visual improvement noticed almost immediately. If after INTACS visual improvement is not adequate, then a corneal transplant can still be performed if needed. In the few cases in which a corneal transplant was performed after an INTACS procedure, there were no complications reported.
What is the procedure for INTACS?
The  INTACS procedure is far less invasive than a corneal transplant or many other surgical procedures of the eye and the INTACS  success rate is high. The surgeons performing the procedure are typically corneal surgeons, having expertise with keratoconus. Each surgeon has also undergone a rigorous training program specific to INTACS for treating patients with keratoconus. Typically, your ophthalmologist, possibly working in tandem with an optometrist will have you undergo a thorough eye examination. Your examination will include a variety of standard ophthalmic tests for this type of procedure, as well as general medical tests and a review of your specific medical history. The operative procedure itself is simple.     Anesthetic drops are used to numb the eye, which is held open throughout the procedure to prevent blinking. The surgery does not require any injections. Step 1: A single, small incision is made in the surface of the cornea. Step 2: To stabilize your eye and ensure proper alignment of the INTACS  inserts, the centering guide is placed on the surface of your eye. During this time, inner layers of the cornea are gently separated by laser  in a narrow circular area to allow for INTACS placement. Step 3: The INTACS  inserts are gently placed in the pocket created by the laser. After the second INTACS insert is placed, the small opening in the cornea is closed with a single suture.     Follow-up visits will be required to monitor the healing process and evaluate the visual benefits of the procedure. Even after a successful procedure, glasses or contacts still may be required to provide you with good vision.     During the follow up period antibiotic, steroid and artificial tear  drops will be prescribed.     Suture is removed  after one month.     Contact Lens/ Glasses are given after 6 weeks.
What are the precautions I need to take after the INTACS surgery?
It is advisable to take rest for 1-2 days after surgery.     Avoid cosmetics around the eyes for one month.     Avoid contact sports/swimming/lifting weights for 3 weeks.     Contact your doctor if you develop pain /redness/discharge.
As with any surgical procedure, there are some risks, including infection. Some patients experience visual symptoms including difficulty with night vision, glare, halos, blurry and fluctuating vision. THESE SYMPTOMS MAY BE TRANSIENT AND RESOLVE  3-6 MONTHS AFTER SURGERY.YOU HAVE TO UNDERSTAND THAT INTACS IS DONE NOT TO ELIMINATE THE USE OF GLASSES /LENS BUT TO STABILISE THE CORNEA AND THIS  IN TURN MAY REDUCE SOME REFRACTIVE POWER OR MAKE THE WEARING OF CONTACT LENSES/GLASSES MORE COMFORTABLE FOR YOU.