Optometry North Bay Visual Health Reference
Viral Conjunctivitis “pink eye” is the most common and most contagious form of acute conjunctivitis. In general the most predominant signs are conjunctival redness, eyelid swelling, watery discharge, light sensitivity, and often a history of upper respiratory tract infection or “cold”.
Treating viral conjunctivitis depends on the offending virus. Most are self limiting (adenovirus) and there are no specific anti-infection treatments. We often recommend supportive treatments in these cases. Sometimes a virus from the Herpes family (cold sores, chickenpox, shingles) is the cause, which responds best to specific antiviral medications.
Bacterial Conjunctivitis is characterized by production of pus and mucous. This can also be contagious, and is generally spread from hand to eye contact, contaminated cosmetics, and poor contact lens hygiene. Generally Bacterial Conjunctivitis shows signs of redness, thick mucous that can glue the eyes shut upon waking, eyelid swelling, and blurry vision.
Treating bacterial conjunctivitis with antibiotic eye drops is highly effective. We also encourage diligent hand washing, and replacing cosmetics and contact lenses, including case.
Allergic Conjunctivitis is generally associated with other allergy symptoms (sinus congestion, etc) and associated with itchy and watery eyes. The inflammation is driven by histamine release in the conjunctiva, and is in response to an environmental allergen. It can be acute or chronic depending on the length of exposure. Common allergens include cat dander, mold, pollen, grass, and dust mites. The mucous associated with allergic conjunctivitis tends to be stringy or ropy, unlike the gob-like mucous of bacterial conjunctivitis.
Treating allergic conjunctivitis can be supportive using cold compresses and frequent use of artificial tears. Symptoms are generally relieved with prescription allergy drops that control the histamine cascade.
Age related macular degeneration (AMD) is an incurable disease and the leading cause of severe vision loss in the over 50 population in North America. AMD affects the macula, the central portion of the retina which is the light sensing tissues at the back of the eye. The macula is unique because it has the highest concentration of light sensing cells (cones) allowing the area to see in high resolution. AMD is generally associated with aging, but there are other risk factors such as genetics, smoking, sunlight exposure, and cardiovascular disease among others. There are 2 types of AMD; dry macular degeneration is considered the most common and least vision threatening, while wet macular degeneration is less common but can be visually devastating.
Dry AMD is a gradual degeneration of the central retina resulting in various degrees of central vision loss. Vision loss can vary from mild loss of detail and contrast to complete central vision loss generally regarded as geographic atrophy. Dry AMD develops slowly, but unfortunately the vision loss is irreversible.
Wet AMD refers to the presence of fluid or blood within the retina. This change can happen rapidly and causes vision changes ranging from mild distortions to severe central vision loss. Vision loss is often sudden and severe. Generally dry AMD is the precursor to wet AMD.
Symptoms of AMD include blurred central vision, distortions of familiar objects, bumps or kinks in straight edges, and immobile dark spots in the central vision. It is difficult to identify the state of the macular degeneration based on symptoms alone. For this reason, patients should contact our office without delay. In these situations we often make use of specialized imaging systems like retinal photography and optical coherence tomography to help us determine the type of macular degeneration and the best course of actions to prevent or potentially reverse any vision loss.
Treatments for AMD depend on the type of disease present. Currently there are no specific treatments for patients with dry AMD. Those with a given stage of dry AMD often benefit from using ocular vitamins which is shown to reduce the risk of vision loss. Other recommendations are made in regards to diet considerations, sunglasses for uv protection, and smoking cessation. Wet AMD is identified by the Optometrist who would refer to an Ophthalmologist for treatment. The treatments are given by injection into the eye to deliver a medication that is highly effective at stopping the leaking blood vessels and helping clear the blood. Despite these measures there is commonly some degree of permanent central vision loss.
In the early stages, AMD has no symptoms. As part of your routine eye examinations we will consider your risk factors of developing this disease as well as carefully look for any signs. We are always counseling patients about reducing their risk of progression as well as the latest treatment and prevention options.
What are Floaters...?
A floater is a vitreous opacity inside of your eye. The vitreous is the clear jelly-like fluid that fills the back chamber in your eye. You may sometimes see small specks moving in your field of vision. These are called floaters. You may often see them when looking at a plain background, such as a blank wall or a blue sky. You may at first mistake them for insects or dust floating in the air. They will appear to move as you move your eyes.
The most common cause of floaters is age-related shrinkage of the vitreous humour. These floaters are often harmless and caused by tiny clumps of gel or cells in the vitreous. A sudden shower of small floaters may stem from retinal bleeding from a retinal tear, which is far more serious and requires prompt treatment.
When floaters first appear, they may be accompanied by what appears to be flashes of light.
What are Flashes...?
When the vitreous gel shrinks it pulls on the retina, and you may see what looks like flashing lights or lightning streaks. If you notice the new or sudden increased appearance of light flashes, it is advisable to have your eyes evaluated to see if the retina has been torn.
Why have my eyes evaluated...?
New floaters or an increase in existing floaters may occur with shrinking of the vitreous gel away from the retina. This usually is harmless, but in some people the vitreous may be firmly attached to the retina in one or more places, and here the retina may be torn as the vitreous pulls away. Torn retina will lead to retinal detachment if not treated. A retinal detachment is perceived as a large persistent shadow in your peripheral vision. If you have these symptoms, you should be seen by your eye care professional to be evaluated for retinal tears.
What will the evaluation tell me…?
A dilated eye examination will tell you what is causing the flashes and floaters, if there is any retinal damage, and if any treatment is necessary at this time.
The tears your eyes normally produce are necessary for overall eye health and clear vision. Dry eye is a common condition where insufficient or poor quality tears do not adequately lubricate and nourish the eyes. Dry eye is often a chronic problem and has many risk factors.
Dry eye has 2 components; low tear volume and increased tear evaporation. Patients can suffer from tear deficient dry eyes due to hormone changes, medications, or autoimmune conditions like rheumatoid arthritis. Another form is evaporative dry eyes caused by poor tear composition. This often stems from eyelid disease especially blepharitis.
Environmental factors like smoking, extended computer use, contact lenses, LASIK, inadequate water intake, and poor air quality (air travel) are also factors. Medications are well known to contribute to dry eyes, particularly an acne medication called Accutane. Patients with autoimmune disease are more prone to dry eyes. An example is Sjogrens's Disease.
Dry eye symptoms include filmy vision, burning, gritty, scratchy feeling eyes, and a feeling there is something foreign in the eyes. The eyes are often boggy looking and red, and ironically will often water which is a reflex from the irritation.
Dry eye treatments vary greatly depending on the severity. Mild dry eyes are affectively relieved using over the counter lubricating drops, artificial tears, and eye ointments. With evaporative dry eyes, hot compresses applied to the closed eyelids is helpful to promote natural tear production, omega-3 supplementation (ie. fish oil, flax), and in some cases low dose antibiotic tablets are required. An effective treatment for tear deficient dry eyes is punctal occlusion, where an artificial plug is inserted into the tear duct to prevent the tears from draining from the ocular surface. This treatment allows the eyes natural tears to remain on the surface. More advanced cases benefit from prescription anti-inflammatory drops that can be dosed in short courses or prescribed for long term use.
Patients with dry eye symptoms benefit from an evaluation with the optometrist to confirm the cause and type of dry eyes and recommend the appropriate treatments.
Glaucoma is a chronic degeneration of the optic nerve that results in irreversible vision loss. The optic nerve consists of a million fibers that relay the sensory stimulus from the eye to the brain. Most commonly adults can develop primary open-angle glaucoma which presents gradually and without symptoms. Less commonly acute angle-closure glaucoma can occur abruptly in those that develop rapidly increased eye pressure resulting in pain and decreased vision. Although glaucoma is most common in adults over age 40, there is a congenital form of the disease and can be found in patients of all ages.
The most significant risk factor associated with glaucoma is increased eye pressure, which is why eye pressure is an integral part of your eye examination. However, glaucoma can happen to patients with perfectly normal eye pressure. Other noteworthy risk factors include a thin cornea, family history, sleep apnea, low blood pressure, and advancing age among others.
Glaucoma is almost always symptom free in the early stages. After significant optic nerve damage, automated visual field testing performed in the office will be able to detect a decrease in the sensitivity in the peripheral vision. Optic nerve imaging (Optical Coherence Tomography) is often employed in the early stages, and has the potential to detect physical changes to the optic nerve even before there are any detectable vision changes. Patients with suspicious looking optic nerves or who have a high risk profile are often monitored closely in office in order to detect changes associated with glaucoma progression.
Glaucoma can also be a complication of previous eye surgery, eye injury, diabetes, and certain medications especially steroid eye drops. Glaucoma can also be secondary to eye abnormalities like pseudoexfoliation syndrome and pigment dispersion syndrome. These conditions are easily identified in adults during a routine eye examination.
Although glaucoma cannot be cured, it is often successfully managed and controlled. Patients with early glaucoma or with high risk eye pressures are treated initially with pressure lowering eye drops or non-invasive laser procedures with an Ophthalmologist. Patients with poorly controlled eye pressure or advance glaucoma are referred to a glaucoma sub-specialist for more advanced surgery. Because glaucoma is a life-long condition it requires monitoring and repeated testing to track progression.
Diabetes is a chronic disease where the body either cannot produce insulin or cannot property use the insulin it produces. Diabetes is a leading cause of blindness in Canada, and is the second only to macular degeneration in causing severe vision loss in adults. Diabetes causes accelerated cataract formation as well as diabetic retinopathy which is a condition caused by damage to the small blood vessels in the retina.
Diabetic retinopathy presents in nearly all diabetics at some stage in their disease. In the early stages the small retinal blood vessels become weak and either bulge (micro aneurysm) or break (dot/blot hemorrhage). This is called non-proliferative diabetic retinopathy. If it advances the retina can swell and the retina tissue can become stressed due to inadequate oxygen supply. Despite the retina being damaged, often this stage of the disease will not cause any vision loss. Vision loss occurs when swelling occurs is the centre of the retina (macular edema). In advanced diabetic retinopathy, oxygen supply can be so poor that the eye grows new blood vessels to compensate for those that are lost. This is known as proliferative diabetic retinopathy and poses a great deal of risk to vision. This form of the disease can cause more serious complications like vitreous hemorrhage, retinal detachment, and glaucoma.
Treating diabetic retinopathy is done in conjunction with an Ophthalmologist. Treatments are aimed at reducing swelling, slowing and often stopping new blood vessel growth, and reducing the overall oxygen demand in the retina.
Preventing diabetic eye disease includes tight blood sugar control, good blood pressure control, and healthy cholesterol levels. It is important to follow the directors of the physician. It is recommended that a Type 1 diabetic have an eye examination 5 years after diagnosis and every year thereafter. Type 2 diabetics should be examined at the time of diagnosis and every year thereafter. Women with diabetes who become pregnant should be closely monitored during pregnancy as well as post-partum.
Diabetes Canada and the Canadian Association of Optometrists have the common goal of educating patients about diabetic retinopathy.