Little Bottle, Big Relief

6/3/14

What you need to know about eye drops.

Have you been staring at a computer all day and your eyes are tired? Have allergies been making your eyes watery and itchy? Are your contact lenses irritating your eyes? If you have experienced any of these conditions, you have probably turned to eye drops for relief.

While eye drops are an easy and effective means of treating a number of eye issues, there are many different eye drops available, both over the counter (OTC) and by prescription. It is wise to know what your underlying condition is before trying to get relief.
eye drops 6.3.14
If your eyes are red and you may want to try a decongestant eye drop, which will shrink the tiny blood vessels in the “whites” of your eyes (sclera), but they also cause dryness so may not be a good choice if you wear contact lenses.
For lens wearers you are better off with a re-wetting drop to lubricate the eye and lens making you more comfortable. Another problem with the decongestant eye drops is over use – which can cause irritation and an increased tolerance that could lead to more redness.

If you suffer from allergies and antihistamine eye drop would be the best choice for relief from itchy, watery, red and swollen eyes. They work by reducing histamine in the eye tissue.

Lubricating eye drops, also known as artificial tears, are for short-term relief caused by temporary situations such as eye strain form computer use, being tired or being outdoors in windy and/or sunny conditions. If the condition is chronic, a prescription eye drop will be the best choice.

It is important to remember that if any of the above symptoms worsen or continue for an extended period of time, it is time to see your eye doctor to determine the underlying cause of your issue and to rule out eye disease. Postponing a visit could also lead to an eye infection.

Prescription drops are used to treat a wide variety of eye diseases such as glaucoma, dry eye and the symptoms of ocular herpes. They are also used to help with healing from cataract surgery, corneal transplants, glaucoma surgery and even Lasik. it is extremely important to use them as often as your ophthalmologist recommends to improve healing and prevent infection.

Because of the ease of applying eye drops researchers are working toward using them to treat other eye diseases. Ocular herpes symptoms are sometimes treated with antiviral and steroid drops. But this only is targeted at the symptoms and not the underlying cause, the herpes simplex virus. Lbachir BenMohamed, PhD and Steven Wechsler, PhD at the University of California, Irvine, Gavin Herbert Eye Instittue have been working to determine what reactivate the herpes simplex virus and develop an eye drop that would either stop the reactivation of the virus or kill it.

Using eye drops to treat age-related macular degeneration (AMD) is also being explored. Researchers at the Institute of Ophthalmology at University College London are working with nanoparticles to deliver anti-VEGF drugs such as Lucentis and Avasitn to the back of the eye via drops. “The study shows that Avastin can be transported across the cells of the cornea into the back of the eye, where is stops blood vessels from leaking and forming new blood vessels, the basis for wet AMD.” While researchers in the Department of Ophthalmology, Tufts University School of Medicine in Boston “reported in their “proof of concept” study that topical application of a compound called PPADS inhibits damage to the tissues in the eye that impacts the individual’s ability to see color and fine detail, as well as reduces the growth of extraneous blood vessels in the back of the eye related to AMD.” It would work in both dry and wet AMD reduce the need for direct injections.

Eye drops, when properly applied, can provide temporary relief from symptoms of eye discomfort. But if the symptoms worsen or continue for an extended period of time, consult your eye doctor. To make sure you apply the eye drops correctly check out the article in our February 2013 newsletter for 12 easy steps to get the drops into your eyes and avoid infection.

One final note – keep your eye drops out of reach of children. Eye drops come in small bottles that are the perfect size for small hands and don’t have the same security tops found on other medications. The FDA has warned that ingredients found in some eye drops that relieve redness have caused abnormal heart rate, decreased breathing, sleepiness, vomiting and even comas in children five and younger that have ingested them. If you child has swallowed eye drops, call the Poison Help Line 800-222-1222.

Susan DeRemerSusan DeRemer
Vice President of Development
Discovery Eye Foundation

What Are The Differences In The Immune System of An Age-related Macular Degeneration Patient?

A symposium was held in Bethesda, Maryland at the National Institutes of Health on March 6, 2014.  The purpose was to bring together clinicians and researchers from a wide variety of background to discuss the recently discovered differences in the function of the immune system in patients with age-related macular degeneration (AMD) and how it relates to aging.  These differences are important to understand because they may lead to new therapeutic approaches to treat people which are high risk for AMD.

Courtesy of National Eye Institute, National Institutes of Health - immune system
Courtesy of National Eye Institute, National Institutes of Health

  • Three researchers associated with the Discovery Eye Foundation attended the one-day conference.  Cristina Kenney, MD, PhD, has worked in the field of AMD for over twelve years and is a leading expert on the genetics and molecular changes in the mitochondria as it related to the retinal cell death associated with AMD.
  • Lbachir BenMohamed, PhD, is an expert immunologist with a tremendous understanding of how the immune system responds to infections and stress.
  • Anthony Nesburn, MD, has been involved in AMD research at both the clinical and research levels.

By attending this meeting, all three researchers gained insight into the importance of the immune system with respect to maintaining a healthy retina and slowing the progression of AMD.

The highlights of the meeting were the following:

1.  Emily Chew, MD (National Eye Institute) reviewed the clinical aspects of the disease stressing that there are many stages of AMD.

The early stage of AMD is diagnosed based upon the medium-size drusen (about the width of an average human hair) that can be seen underneath the retina.  There may not be any visual changes in these patients.

The intermediate stage of AMD is when subjects have larger drusen and some degree of retinal pigment epithelial cell drop out.  These patients may not have vision loss or other symptoms.

The late stages of AMD which can be categorized into the dry form (geographic atrophy) which has significant loss of the retinal pigment epithelial cells and overlying photoreceptor cells.  Presently there in no treatment for this type of AMD.

These individuals can have changes that cause decreased vision.  The second form of late AMD is the wet form (neovascular), which has growth of abnormal blood vessels beneath the retina that can cause significant loss of vision.  The treatments for this type of AMD are anti-VEGF medications that block the growth of these vessels and help maintain good visual acuity.

2.  Anand Swaroop, PhD (National Eye Institute) reviewed the genetics of AMD and summarized the work of numerous laboratories.  It is now recognized that there are over 20 different genes associated with AMD.  These genes fall into the categories of those involved with Complement Activation, Cholesterol Pathway, Angiogenesis, Extracellular Matrix and Signaling Pathways.  Many of these genes have additive effects, meaning that if a patient has more than one high risk gene, then the likelihood of developing AMD increases.  While we have learned a lot about the genes that are important, we still do not have any gene therapies that can be used to treat AMD.

3.  Six different speakers presented their data related to animal models of AMD and it was agreed that there is not a “perfect” model because most of the animals do not have a macula, the region of the retina that is affected the most by AMD.  However, there is still a lot to be learned by using the models that we do have because if we can better understand the basic pathways involved, then we can block or modify the pathways to prevent the damage.

4.  Jayakrishna Ambati, PhD (University of Kentucky) presented data showing that there is a deficiency of an enzyme called DICER1 in the retinal pigment epithelial cells which leads to increased activation of inflammation via a protein complex called the inflammasome.  He described some of the signaling pathways which are involved in the inflammasome activation.  This is important because these pathways can become targets for treatment of the dry form of AMD.

5.  Jae Jin Chae, PhD (National Human Genome Research Institute) also talked about the role that inflammation plays in the development of AMD.  The data presented reviewed the pathways involved with activation of the inflammasomes which is the first step in a cascade of events that result in inflammatory diseases.  They have identified a calcium-sensing receptor (CASR) which triggers the activation of the NLRP3, a key component of the inflammasome.  Understanding how this series of events works allows researchers to develop medications to block or interfere with the pathway and therefore decrease the levels of inflammation.  

Dr. M. Cristina KenneyM. Cristina Kenney, MD, PhD
Professor and Director of Ophthalmology Research
School of Medicine, Dept. of Ophthalmology
University of California, Irvine