Eye Anatomy.
Function of the Eye
The eye is a complex organ that functions much like a camera, converting light into electrical signals. These signals are sent to the brain, where they are processed into the images we see.
Each part of the eye plays a crucial role in providing clear vision and allowing us to navigate our environment.

Structures of the Eye
Cornea
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The first entry point for light into the eye.
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Kept moist by constant tear production.
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Dry eyes can blur vision by affecting the light passing through this structure.
Pupil
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Controls how much light enters the eye.
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Small (constricted): Less light enters.
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Large (dilated): More light enters, allowing for a more thorough internal eye exam.
Iris
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The coloured part of the eye.
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Controls pupil size based on light conditions.
Lens
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Focuses light onto the retina.
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Adjusts shape for reading up close or viewing distant objects.
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With age, the lens loses flexibility, making it harder to adjust focus. This results in the need for reading glasses later in life.
Vitreous
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A gel-like substance that fills the eye’s interior.
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Responsible for the production of floaters (tiny shadows in vision).
Retina
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A thin tissue layer at the back of the eye.
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Functions like film in a camera, capturing light and converting it into electrical signals.
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Contains blood vessels for nourishment.
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Processes fine detail, color vision, and peripheral vision.
Macula & Fovea
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Macula: The area of the retina responsible for color vision and fine detail.
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Fovea: The center of the macula, where cells for central vision are most concentrated.
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Diseases like AMD (Age-related Macular Degeneration) can damage the macula, causing central vision loss.
Optic Nerve
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The communication system between the retina and the brain.
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Transmits visual information to the brain to create the images we see.
Eye Health.
UV Protection for Your Eyes
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Will I need to use eye drops?You will be given a prescription for eye drops, please use these as prescribed. If you feel the drop has not gone in properly you may place another drop in the eye. If using more than one drop, please allow a few minutes in between the drops.
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How should I sleep at night after surgery?Instructions are given by the surgeon at time of discharge or at your one day post operative appointment.
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When can I return to work?In most cases, the recommended time off work is 1-2 weeks. This may be shorter or longer depending on the type of surgery, and also the type of work you do. (For a retinal detachment, or surgery requiring a gas bubble, some people may need up to one month off work)
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What can I expect at my appointment on the day after surgery?After removing the patch, your eye will be examined. Expect the vision to be very blurry at this visit. Vision improvement is gradual and varies with every patient.
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How should I prepare for surgery?Please make sure your Pre-op Medical is complete and faxed back to our office prior to surgery date. You will need to arrange for someone to drive to the surgery and pick you up. You cannot have anything to eat or drink as of midnight the night prior to your surgery. It is okay to take important medication the morning of surgery with a small sip of water(i.e. Blood pressure, heart, anti-rejection, anxiety). Please make sure you bring 2 pieces of ID. ***You can arrange for home-care through your Family Doctor’s office if you live alone and need help at home (i.e. Administer eye drops, meal, etc)***
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When can I resume normal activities?This will depend on many factors: Your age, activity level before the surgery, the vision in your other eye, the type of surgery you had and the particular problem you had that required the surgery. In general, activities may be safely resumed according to the following schedule:
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How long will I be at the hospital?Patients are usually at the hospital up to 6 hours from check in to discharge.
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How do I prevent infection?Thankfully, due to modern surgical techniques, the risk of infection is much lower than it used to be and the risk of a serious infection is much less than 1%. However if this happens, the outcome can be devastating, and result in severe loss of vision or even blindness and loss of the eye. The risk of infection is greatest in the first 7 days after surgery, and then declines rapidly. For the first week after surgery, please wash your hands frequently with antiseptic soap or gel, especially prior to putting in your eye drops or touching anywhere near the eye. Please use a clean tissue when wiping your eye.
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How long will I wear a patch?Your eye patch will be removed on the day following surgery at your one day post operative appointment. Some patients prefer wearing the patch for a few more days while the eye is healing, since the blurry vision after surgery can be frustrating, this is OK. We recommend using the hard shield over the eye at bedtime for the first week (no gauze or patch is required underneath).
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How soon after my eye surgery can I update my prescription glasses?It depends on the procedure you had, generally this can be done at 6-8 weeks but is best to confirm with your doctor.
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When will I be notified about the time of my surgery?You will be called the day before surgery (between 3-7 pm) to notify you of your arrival time. If your surgery is scheduled on a Monday, then you will be called the Friday before your surgery date.
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What are my restrictions after surgery?No heavy lifting (nothing over 10lbs initially) Avoid bending over Avoid strenuous exercises for 2 weeks No swimming pools for 2 weeks No driving for 2 weeks No flying/No travel to high altitudes if you have gas in the eye (varies from 3 weeks to 10 weeks depending of which gas bubble is in eye)
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How will I feel after surgery?Retina surgery is an invasive eye surgery. Expect the eye to hurt after surgery once the local anesthesia wears off. Much of this can be relieved with pain medicine (acetaminophen and/or ibuprofen). We strongly encourage the use of pain medicine every 4-6 hours after surgery unless there is a contraindication. If your pain worsens or is not relieved shortly after using pain medication, or if you have nausea please call us.
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How long will my surgery last?Retina surgery usually lasts between 45 minutes to 2 hours. We can be more specific with you according to what surgical procedure you are undergoing.
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What can I expect in regards to my vision?Visual improvement after retinal surgery is gradual and depends on the condition and procedure you have. Generally recovery is gradual.
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Types of claims by ManufacturersManufacturers have developed new sunglasses designed to protect eyes from the sun’s harmful effects. They promise protection from ultraviolet light and other kinds of natural radiation. It is more important to protect your eyes from some kinds of light than others. “Blocks 99% of ultraviolet rays”: You should always buy sunglasses with this feature. Long-term exposure to ultraviolet (UV) radiation in sunlight is linked to eye disease. Both plastic and glass lenses absorb some UV light, but UV absorption can be improved by adding chemicals to the lens material during manufacturing or by applying special lens coatings. Shop for sunglasses that block 99 or 100% of all UV light. Some manufacturers’ labels say “UV absorption up to 400nm.” This is the same thing as 100% UV absorption. “Blocks 90% of infrared rays”: Infrared wavelengths are invisible (they are longer than light rays that you can see) and produce heat. Sunlight has low levels of infrared rays, and the eye tolerates infrared well. Some sunglasses manufacturers make health claims for their products based on infrared protection, but research has not shown a close connection between eye disease and infrared rays. “Blue-blocking”: Whether blue light is harmful to the eye is still controversial. Lenses that block all blue light are usually amber and make your surroundings look yellow or orange. The tint supposedly makes distant objects appear more distinct, especially in snow or haze. For this reason, amber sunglasses are popular among skiers, hunters, boaters and pilots. “Polarized”: Polarized lenses cut reflected glare – sunlight that bounces off smooth surfaces like pavement or water. They can be particularly useful for driving and fishing. Polarization has nothing to do with UV light absorption, but many polarized lenses are now combined with a UV-blocking substance. Check the label to make sure the lenses provide maximum UV protection. “Mirror-coated”: Mirror finishes are thin layers of various metallic coatings on an ordinary lens. Although they do reduce the amount of visible light entering your eyes, do not assume they will fully protect you against UV radiation. “Wraparound”: Wraparound glasses are shaped to keep light from shining around the frames and into your eyes. Studies have shown that enough UV rays enter around ordinary eyeglass frames to reduce the benefits of protective lenses. Large-framed wraparound sunglasses can protect your eyes from all angles. “Gradient”: Gradient lenses are permanently shaded from top to bottom or from top and bottom toward the middle. Single-gradient lenses (dark on top and lighter on the bottom) can cut glare from the sky but allow you to see clearly below. They are useful for driving because they don’t dim your view of the dashboard. But they’re not as good on snow or at the beach, especially if they’re clear on the bottom. Double-gradient lenses (dark on top and bottom and lighter in the middle) may be better for sports where light reflects up off the water or snow, such as sailing or skiing. Double-gradient lenses are not recommended for driving, because they make the dashboard appear dim. “Photochromic”: A photochromic glass lens automatically darkens in bright light and becomes lighter in low light. Most of the darkening takes place in about half a minute, while the lightening takes about five minutes. They come in a uniform or gradient tint. Although photochromic lenses may be good UV-absorbent sunglasses (again, the label must say that), it takes time for them to adjust to different light conditions. “Ground and polished”: Some non-prescription glasses are ground and polished when they are manufactured to improve the quality of the lenses. Non-prescription lenses that are not ground and polished will not hurt your eyes. You do want to make sure that the lenses you buy are made properly. To judge the quality of non-prescription sunglasses, look at something with a rectangular pattern such as floor tile. Hold the glasses at a comfortable distance and cover one eye. Move the glasses slowly from side to side, then up and down. If the lines stay straight, the lenses are fine. If the lines wiggle, especially in the center of the lens, try another pair. “Impact resistant”: All sunglasses must meet impact standards set by the Federal Food and Drug Administration. No lens is truly unbreakable, but plastic lenses are less likely than glass lenses to shatter when hit by a ball or stone. Most non-prescription sunglass lenses are plastic. Polycarbonate plastic, used in many sports sunglasses, is especially tough but scratches easily. If you buy polycarbonate lenses, look for ones with scratch-resistant coatings.
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Special situationsOrdinary sunglasses, even the best, cannot protect your eyes from certain intense light sources. Arc welding, tanning lights, snowfields or gazing directly at the sun (especially during a solar eclipse) can damage your eyes. Looking at any of these light sources without adequate protection can cause a painful corneal condition called photokeratitis or even a permanent loss of central vision.
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RecommendationsGiven the increased risk of skin cancer and some types of cataract associated with UV exposure, the public should protect their eyes, especially when exposed to excessive sunlight. If there is sufficient UV present to cause sunburn, a hat and sunglasses are advised. People with high UV exposure, especially those spending prolonged time in the sun or in the snow during the middle of the day, or those exposed to intense artificial sources such as welding arcs or suntanning lamps, should consider using close-fitting goggles or sunglasses with lenses that absorb all UV-B and UV-A, and possibly a substantial portion of blue light as well. Consumers should be able to determine the UV and visible light absorptive properties of sunglasses. Manufacturers are encouraged to adopt a simple coding system for sunglasses that clearly indicates the degree of UV-B and UV-A radiation, as well as the blue and visible light absorption.
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Those at special riskThere are some people who are at greater risk for UV-related eye damage. People with certain eye diseases, such as macular degeneration or retinal dystrophies, need to protect their eyes whenever they go outside, no matter how briefly. Cataract surgery patients One million Americans have cataract surgery each year. During this procedure, the eye’s natural lens is removed, leaving the eye more vulnerable to UV light. During or after cataract surgery, the natural lens is usually replaced by an intraocular lens (IOL). Older intraocular lenses absorb much less UV light than ordinary glass or plastic eyeglass lenses. Manufacturers of IOLs now make many of their products UV absorbent. If you have had cataract surgery and your IOL is not the newer UV-absorbent type, you may want to wear sunglasses and a hat for added protection. Contact lens wearers Contact lenses by themselves will not protect your eyes from UV light. Many types of contact lenses are available with UV protection. If you do not have contact lenses that absorb UV light, you still need to protect your eyes with sunglasses. Photosensitizing drugs Photosensitizing drugs–drugs that make your skin more sensitive to light –can make your eyes more sensitive to light as well. You should discuss precautions with your ophthalmologist if you are taking any of the following drugs: Psoralens (used in treating psoriasis) Tetracycline Doxycycline Allopurinol Phenothiazine Wear UV-absorbent sunglasses and a hat whenever you go outside for as long as you take the drug.
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Lense DarknessA medium lens is good for day-to-day wear, but if you use the glasses for very bright conditions, choose a darker lens. The color and the degree of darkness do not tell you anything about the lenses’ ability to block UV light.
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Ocular Hazards of UV ExposureThere are many benefits from an outdoor lifestyle. However, it is important to recognize that sunlight is a substantial source of UV radiation which may damage tissues of the eye. At risk from sunlight, or strong artificial UV sources, are the ocular surface (snowblindness and pterygium), the lens (cataract), and the retina (eclipse blindness and macular degeneration). Ultraviolet radiation is divided into two major bands, UV-A and UV-B. UV-A is longer wavelength radiation, close to blue in the visible spectrum, that usually induces skin tanning and browning, and has been implicated in skin aging. UV-B is more active, shorter wavelength radiation that causes blistering sunburn and is associated with skin cancer. Excessive exposure to intense sunlight, or to an artificial source such as a welding arc or suntanning lamp, can burn the surface of the eye (cornea and conjunctiva) much like sunburn on the skin. The risk is highest in environments where much UV is reflected, such as snow. Although snowblindness (photokeratitis) may be painful, it is usually self-limited with recovery in one or two days. Chronic sun exposure also contributes to other ocular surface problems such as pterygium. Cataract (clouding of the lens) is a major health problem in the United States and the most common surgical procedure among the elderly. Globally, cataract causes half of all serious visual impairment and affects 20 million people. Several laboratory and epidemiological studies have suggested a link between sun exposure and cataract. There is debate about how close this linkage is for one common form of cataract (nuclear sclerosis), but measures to reduce UV exposure should reduce the risk of at least two types of cataract (cortical and posterior subcapsular). Macular degeneration (age-related damage in the central vision area) is the major cause of blindness among Americans over age 50, and is an increasingly important problem as our population ages. Both UV and deep blue light have been shown to be damaging to the retina in laboratory studies, and a number of scientists have postulated that UV and blue light may contribute to retinal aging and macular degeneration. Epidemiological studies to date have not demonstrated any clear relationship, except possibly for some severe forms of the disease that seem associated with a history of greater blue light exposure. Protection from UV (including the longer UV-A wavelengths) and from too much blue light may thus be prudent. Just wearing a hat will reduce exposure by roughly half. Sunglasses are capable of eliminating virtually all of the UV, but it may be hard to tell from the label what a particular pair of sunglasses will do. Most pairs labelled “UV absorbing” will absorb most of the UV-B, but there is no present standard of labelling that adequately indicates UV-A or blue protection.
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When to Call for HelpCall our office at +1 (780) 448-1801 immediately if you experience: Severe eye pain not relieved by Tylenol. Increased redness (some bloodshot appearance is normal). Significant decrease in vision in the operated eye. Nausea and/or vomiting.
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Hygiene & Self-CareDay 1: Do not shower. Instead: Take a bath, but avoid soap or water in the eye area. Gently wash your face with a clean cloth, pat dry without rubbing. If something enters your eye, rinse it out with artificial tears. Avoid makeup for 7 days after surgery. Stay away from smoke, dust, and other irritants for one week. Use a humidifier to prevent your eyes from drying out. If you have a gas bubble, do not fly until it has dissipated. Follow head positioning instructions if provided by your doctor for optimal healing.
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Eye Care & ProtectionExpect some discharge for the first few days (blood-tinged, yellow, or watery). Always protect the operated eye: During the day: Wear sunglasses or the shield from your post-op kit. At night: Wear the shield secured with tape. First week: Place an eye pad under the shield to absorb any tears. Avoid lifting anything heavy or causing exertion for two weeks.
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Common Post-Surgery SymptomsLight sensitivity, scratchiness, and irritation are normal for 48–72 hours. Red, irritated eyes are expected and should improve within a few days.
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Appointments & Follow-UpsOur office will contact you between 2pm and 5pm one business day before surgery to provide the following: Surgery check-in time 1-day post-operative appointment 2-week post-operative appointment
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Post-Surgery GuidelinesGo directly home and rest for the remainder of the day. Avoid watching television for the rest of the day. Use your prescribed antibiotic eye drops and any other medications as directed. Continue using all prescribed drops until your post-operative check-up, where further instructions will be given.
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Post Operative Instructions Example*This is an example of the form your surgeon will fill out with instructions specific to your situation* Patching of Operative Eye __ 1st Night Post Surgery __ Day(s) Post Surgery __ Week(s) Post Surgery Shielding of Operative Eye __ 1st Night Post Surgery __ Night(s) Post Surgery __ Week(s) Post Surgery Eye Drops __ Tobradex 4 X Daily for __ Week(s) __ Predforte 4 X Daily for __ Week(s) __ Vigamox 4 X Daily for __ Week(s) Pain Medication Plain Tylenol / Tylenol #3 – max 2 pills every 4 hours Positioning __ Face Down __ Right Side Down __ Left Side Down __ Head Elevated ____ Degrees __ Sitting up __ No Position Required For __ Day(s) __ Week(s) *Showering- one day after surgery* Follow up Appointments: Day 1 Post Surgery: Date & Time: __________________________________ Royal Alex Hospital- Unit 22/Eye Clinic (#111) OR ARC- Suite 400, 10924-107 Ave 2 Weeks Post Surgery: Date & Time: ________________________________ Royal Alex Hospital- Unit 22/Eye Clinic (#111) OR ARC- Suite 400, 10924-107 Ave Special Instructions: Pain after vitrectomy should be mild and treatable with pain Tylenol Pain after scleral buckle surgery is moderate and treatable with plain Tylenol or Tylenol #3. PLEASE CALL 780-448-1801 if you have increasingly severe eye pain or if you are nauseated and vomiting
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Contacting Your DoctorAfter leaving the hospital, you can reach your doctor by calling our office at +1 (780) 448-1801. Office hours: 8:30 AM – 5:00 PM, Monday to Friday. After hours: Our answering service can transfer your call to your doctor if needed.
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Activity ScheduleDay of Surgery Rest for the entire day. Avoid rubbing your eyes. Use lubricating drops instead. Avoid staring without blinking to keep eyes moist. No alcohol for 48 hours. 24 Hours After Surgery Bathe in the morning but avoid getting soap or water in your eyes. Limit yourself to light activities. 48 Hours After Surgery Showering is allowed, but bathing is recommended. Reading and watching TV is okay as long as eye lubrication is maintained. Day 4 Resume low-risk exercise (e.g., treadmill, stationary bike). Computer work is allowed, but lubricate eyes regularly. Remain cautious of activities that pose a risk to your eyes.
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Deep learning in ophthalmology: a review.Grewal PS, Oloumi F, Rubin U, Tennant MTS. Can J Ophthalmol. 2018 Aug;53(4):309-313. doi: 10.1016/j.jcjo.2018.04.019. Epub 2018 May 30. PMID: 30119782 Review. Read Here
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Tele-Ophthalmology for Age-Related Macular Degeneration and Diabetic Retinopathy Screening: A Systematic Review and Meta-Analysis.Kawaguchi A, Sharafeldin N, Sundaram A, Campbell S, Tennant M, Rudnisky C, Weis E, Damji KF. Telemed J E Health. 2018 Apr;24(4):301-308. doi: 10.1089/tmj.2017.0100. Epub 2017 Aug 7. PMID: 28783458 Free PMC article. Read Here
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What if I’m diabetic?If you are diabetic, we recommend bringing a snack with you in case of increased waiting times. It's also helpful to eat before your appointment if possible, as wait times can range from 1-2 hours, depending on the day.
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What if I already know my potential diagnosis?If you have an idea of your potential diagnosis, feel free to print off the relevant information sheet from our website and bring it with you.
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Should I prepare questions for the doctor?Yes, feel free to bring a list of questions you would like to ask your doctor about your condition. It can be helpful to write these down to ensure you don’t forget anything during the consultation.
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Will the pupil dilation affect my vision?Yes, pupil dilation can last from 4-6 hours after your appointment. You may experience blurry vision and increased sensitivity to light during this time.
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How long will my appointment last?Your appointment is expected to last approximately 1-2 hours, including pupil dilation, vision screening, and consultation.
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Can I bring small children with me?For the comfort of all patients, we suggest that you do not bring small children, unless absolutely necessary. If you must bring them, please plan accordingly for their care during the appointment.
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Is there anything else I should bring?Please bring a list of your current medications to help keep your file up to date, which is especially important in case of an emergency.
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Should I bring anything to help with the dilation effects?Yes, please bring sunglasses for your comfort, as your eyes will be more sensitive to light due to pupil dilation.
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Do I need a driver for my appointment?We strongly recommend that you bring a driver or arrange for alternate transportation to get home after your appointment, as your vision will be affected by dilation.
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What should I bring to the appointment?- Corrective eyeglasses (if applicable) - A list of current medications - If you are diabetic, please bring a snack and any necessary medications.
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What about insurance and third-party forms?You will be responsible for completing any insurance or third-party forms. Please bring all necessary documentation with you.
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Can I bring small children?We suggest not bringing small children to your appointment unless necessary, to ensure comfort for all patients. If you must bring children, please plan accordingly for their care during the visit.
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How long will my appointment take?The length of your appointment may vary, but expect it to take approximately 1-2 hours, depending on the tests required and your treatment plan.
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What should I expect during my return visit?Depending on your condition, many of the tests you had on your first visit will likely be repeated. This includes tests like OCT photos, vision screening, an eye pressure check, and dilation. Additional testing may be required if your condition has changed or if more information is needed.
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Do I need to bring anything specific if I have diabetes?Yes, if you're diabetic, please bring a snack and aim to eat before your appointment if possible. The wait can sometimes be long, and it's important to maintain your blood sugar levels.
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Do I need a driver?As with your first visit, if dilation is involved, it is recommended to bring a driver or arrange for alternate transportation home, as your vision will be affected by dilation.
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Will I have any tests if I'm coming in for treatment?Yes, each treatment visit typically involves some pre-treatment tests. These usually include a new set of OCT photos, vision screening, an eye pressure check, and dilation. However, the exact tests may vary depending on your condition.
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What should I bring to my appointment?A list of current medications to ensure your file is up to date. Questions for your doctor about your condition, especially if you have any concerns or new symptoms to discuss. If you are diabetic, please bring a snack and try to eat before your appointment, as wait times can range from 1-3 hours, depending on the day.
Sunglasses have been popular with people for years, both for comfort and as a fashion accessory. Ophthalmologists (medical eye doctors) now believe there is another reason to wear sunglasses – to protect the long-term health of your eyes. Results from a dozen studies over the last 10 years suggest that long hours in the sun without proper eye protection increase your chances of developing eye disease.
In 1988, a group of ophthalmologists studied 838 Chesapeake Bay fishermen who had spent years working on the water. The fishermen who wore no eye protection had three times as many cataracts as those who wore sunglasses or a brimmed hat. A cataract is a clouding of the eye’s natural lens. Based on this study and others, ophthalmologists now recommend that you wear UV-absorbent sunglasses and a brimmed hat whenever you’re in the sun long enough to get a suntan or a sunburn, especially if you live at a high elevation or near the equator.
Low Vision Aids
When you are faced with low vision, there are options for continuing the activities you like to do. Most individuals start out with large-print books, the use of a magnifier, improved lighting and using high contrast materials, such as black pen on white paper so the writing stands out more.
Our office can refer you for a low vision assessment at the Canadian National Institute for the Blind (CNIB), where they can suggest a variety of additional aids and support to help maintain your independence.
There are also options available online for those who like to use their computer depending on the system that you use. Click here to find an example of what is offered from Microsoft: screen magnifiers, speech recognition, talking word processors, screen readers, etc.
Important Links.
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AMD Alliance: for AMD support and information
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Canadian National Institute for the Blind: for information about low vision tools, assessment and support
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Canadian Uveitis Society: for information about Uveitis
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Stargardt’s Disease: information on this hereditary disease
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Von Hippel Lindau Disease: information on this hereditary disease