Hello teachers!
I hope the information I have been posting for you have been useful for your English lessons in general.
I am teaching English for Specific Purposes to 5th medical students, so we are using some short videos about different diseases regarding the Book Units.
At the moment they are doing a project work regarding some Eye disorders. I would like to share with you some of my students' project work that include lot of information,graphs, images, tables among other issues related to the Eye disorder selected.
I will add some of their pictures later on.
Hope keeping in touch and looking forward to see your comments!
Thanks,
Yordanka
Members:
Idania Nuñez Glez
Kenny Barbeyto Jimenez
Carlos Enrique Delgado Paredes
Adrian Garcia Moya
Havana City
2012
DiabeticRetinopathy
Introduction
A rare disease until 1921, when the discovery of insulin resulted in a dramatic improvement in life expectancy for patients with diabetes mellitus, it is now a leading cause of blindness in the Cuba. The retinopathy of diabetes takes years to develop but eventually appears in nearly all cases(see Fig. 1). Regular surveillance of the dilated fundus is crucial for any patient with diabetes. In advanced diabetic retinopathy, the proliferation of nonvascular vessels leads toblindness from vitreous hemorrhage, retinal detachment, and glaucoma. These complications can be avoided in most patients by administration of panretinal laser photocoagulation at the appropriate point in the evolution of the disease.
Diabetic retinopathy, the most common diabetic eye disease, occurs when blood vessels in the retina change. Sometimes these vessels swell and leak fluid or even close off completely. In other cases, abnormal new blood vessels grow on the surface of the retina.
The retina is a thin layer of light-sensitive tissue that lines the back of the eye. Light rays are focused onto the retina, where they are transmitted to the brain and interpreted as the images you see. The macula is a very small area at the center of the retina. It is the macula that is responsible for your pinpoint vision, allowing you to read, sew or recognize a face. The surrounding part of the retina, called the peripheral retina, is responsible for your side or peripheral vision.(see Fig. 2).
Diabetes Mellitus is the leadingcause of blindness between the ages of 20 and 74 in the Cuba. The gravity of this problem is highlighted by the finding that individualswith DM are 25 times more likely to become legally blind than
individuals without DM. Blindness is primarily the result of progressivediabetic retinopathy and clinically significant macular edema.
Objectives
1- Look up informationabout Diabetic Retinopathy.
2- Delve deeply into the knowledge about symptoms, diagnosis and treatment.
3- Know the principal complications and the prognosis to DR.
Development
Most often, diabetic retinopathy has no symptoms until the damage to your eyes is severe.
Symptoms of diabetic retinopathy include:
Blurred vision and slow vision loss over time
Floaters
Shadows or missing areas of vision
Trouble seeing at night
Many people with early diabetic retinopathy have no symptoms before major bleeding occurs in the eye. This is why everyone with diabetes should have regular eye exams.
There are two types of diabetic retinopathy:
1. Background or nonproliferative diabetic retinopathy (NPDR)
Nonproliferative diabetic retinopathy (NPDR) is the earliest stage of diabetic retinopathy. With this condition, damaged blood vessels in the retina begin to leak extra fluid and small amounts of blood into the eye. Sometimes, deposits of cholesterol or other fats from the blood may leak into the retina.
NPDR can cause changes in the eye, including:
•Microaneurysms: small bulges in blood vessels of the retina that often leak fluid.
•Retinal hemorrhages: tiny spots of blood that leak into the retina.
•Hard exudates: deposits of cholesterol or other fats from the blood that have leaked into the retina.
•Macular edema: swelling or thickening of the macula caused by fluid leaking from the retina's blood vessels.
The macula doesn't function properly when it is swollen. Macular edema is the most common cause of vision loss in diabetes.
•Macular ischemia: small blood vessels (capillaries) close. Your vision blurs because the macula no longer receives enough blood to work properly.
Many people with diabetes have mild NPDR, which usually does not affect their vision. However, if their vision is affected, it is the result of macular edema and macular ischemia.Watch how macular edema and macular ischemia affect your eyes.
2- Proliferative diabetic retinopathy (PDR)
Proliferative diabetic retinopathy (PDR) mainly occurs when many of the blood vessels in the retina close, preventing enough blood flow. In an attempt to supply blood to the area where the original vessels closed, the retina responds by growing new blood vessels. This is called neovascularization. However, these new blood vessels are abnormal and do not supply the retina with proper blood flow. The new vessels are also often accompanied by scar tissue that may cause the retina to wrinkle or detach.
PDR may cause more severe vision loss than NPDR because it can affect both central and peripheral vision. PDR affects vision in the following ways:
Vitreous hemorrhage: delicate new blood vessels bleed into the vitreous — the gel in the center of the eye — preventing light rays from reaching the retina. If the vitreous hemorrhage is small, you may see a few new, dark floaters. A very large hemorrhage might block out all vision, allowing you to perceive only light and dark. Vitreous hemorrhage alone does not cause permanent vision loss. When the blood clears, your vision may return to its former level unless the macula has been damaged.
Traction retinal detachment: scar tissue from neovascularization shrinks, causing the retina to wrinkle and pull from its normal position.
Macular wrinkling can distort your vision. More severe vision loss can occur if the macula or large areas of the retina are detached.
Nonvascular glaucoma: if a number of retinal vessels are closed, neovascularization can occur in the iris (the colored part of the eye). In this condition, the new blood vessels may block the normal flow of fluid out of the eye. Pressure builds up in the eye, a particularly severe condition that causes damage to the optic nerve.
Watch how vitreous hemorrhage affects your eyes.
Exams and Tests
The health care provider can diagnose diabetic retinopathy by dilating your pupils with eye drops and then carefully examining the retina. A retinal photography or fluorescein angiographytest may also be used.
If you have nonproliferative diabetic retinopathy, your health care provider may see:
•Blood vessels in the eye that are larger in certain spots (called microaneurysms)
•Bloom vessels that are blocked
•Small amounts of bleeding (retinal hemorrhages) and fluid leaking into the retina
If you have proliferative retinopathy, your health care provider may see:
•New blood vessels starting to grow in the eye that are fragile and can bleed
•Small scars developing on the retina and in other parts of the eye (the vitreous)
Treatment
The most effective therapy for diabetic retinopathy is prevention. Intensive glycemic and blood pressure control will delay the development or slow the progression of retinopathy in individuals with either type 1 or type 2 DM. Paradoxically, during the first 6 to 12 months of improved glycemic control, established diabetic retinopathy may transiently worsen.(See fig. 3)
Fortunately, this progression is temporary, and in thelong term, improved glycemic control is associated with less diabeticretinopathy. Individuals with known retinopathy are candidates forprophylactic photocoagulation when initiating intensive therapy. Onceadvanced retinopathy is present, improved glycemic control impartsless benefit, though adequate ophthalmologic care can prevent mostblindness.
Regular, comprehensive eye examinations are essential for all individuals
with DM. Most diabetic eye disease can be successfullytreated if detected early. Routine, nondilated eye examinations by theprimary care provider or diabetes specialist are inadequate to detectdiabetic eye disease, which requires an ophthalmologist for optimalcare of these disorders. Laser photocoagulation is very successful inpreserving vision. Proliferative retinopathy is usually treated with panretinallaser photocoagulation, whereas macular edema is treated withfocal laser photocoagulation.
Although exercise has not been conclusivelyshown to worsen proliferative diabetic retinopathy, most ophthalmologistsadvise individuals with advanced diabetic eye disease tolimit physical activities associated with repeated Valsalva maneuvers.Aspirin therapy (650 mg/d) does not appear to influence the naturalhistory of diabetic retinopathy, but studies of other antiplatelet agentsare under way
Several procedures or surgeries are the main treatment for diabetic retinopathy.
Laser eye surgery creates small burns in the retina where there are abnormal blood vessels. This process is called photocoagulation. It is used to keep vessels from leaking or to get rid of abnormal, fragile vessels.
•Focal laser photocoagulation is used to treat macular edema.
•Scatter laser treatment or panretinal photocoagulation treats a large area of your retina. Often two or more sessions are needed.
A surgical procedure called vitrectomy is used when there is bleeding (hemorrhage) into the eye. It may also be used to repair retinal detachment.
Drugs that prevent abnormal blood vessels from growing, and corticosteroids injected into the eyeball are being investigated as new treatments for diabetic retinopathy.
If you cannot see well:
•Make sure your home is safe so you do not fall
•Organize your home so that you can easily find what you need
•Get help to make sure you are taking your medicines correctly
Prognosis
You can improve your outcome by keeping good control of your blood sugar and blood pressure.
Treatments can reduce vision loss. They do not cure diabetic retinopathy or reverse the changes that have already occurred.
Once proliferative retinopathy occurs, there is always a risk for bleeding. You will need to be monitored regularly, and you may need more treatment.
Possible Complications
Other problems that may develop are:
•Cataracts
•Glaucoma -- increased pressure in the eye that can lead to blindness
•Macular edema -- if fluid leaks into the area of the retina that provides sharp vision straight in front of you, your vision becomes more blurry
•Retinal detachment -- scarring may cause part of the retina to pull away from the back of your eyeball
When you the patient should see goto a doctor
Call for an appointment with an eye doctor (ophthalmologist) if you have diabetesand you have not seen an ophthalmologist in the past year.(See fig.4)
Call your doctor if any of the following symptoms are new or are becoming worse:
•You cannot see well in dim light.
•You have blind spots.
•You have double vision (you see two things when there is only one).
•Your vision is hazy or blurry and you cannot focus.
•You have pain in one of your eyes.
•You are having headaches.
•You see spots floating in your eyes.
•You cannot see things on the side of your field of vision.
•You see shadows.
Prevention
Tight control of blood sugar, blood pressure, and cholesterol is very important for preventing diabetic retinopathy.
Do not smoke. If you need help quitting, ask your doctor or nurse.
You may not know there is any damage to your eyes until the problem is very bad. Your doctor can catch problems early if you get regular exams. You will need to see an eye doctor who is trained to treat diabetic retinopathy.
Begin having eye examinations as follows by an eye doctor skilled in the treatment of diabetic retinopathy:
•Children older than 10 years who have had diabetes for 3 - 5 years or more
•Adults and adolescents with type 2 diabetes soon after diagnosis
•Adolescents and adults with type 1 diabetes within 5 years of diagnosis
•After the first exam, most patients should have a yearly eye exam.
If you are beginning a new exercise program or are planning to get pregnant, have your eyes examined. Avoid resistance or high-impact exercises, which can strain already weakened blood vessels in the eyes.
If you are at low risk, you may need follow-up exams only every 2 - 3 years. The eye exam should include dilation to check for signs of retinal disease (retinopathy).
Conclusions
1.Diabetic retinopathy is the most common diabetic eye disease.
2.Many people with early diabetic retinopathy have no symptoms before major bleeding occurs in the eye.
3.A retinal photography or fluorescein angiography test may also be used.
4.The most effective therapy for diabetic retinopathy is prevention.
5.The principals’s complications are Cataracts, Glaucoma and Macular edema.
6.They do not cure diabetic retinopathy or reverse the changes that have already occurred.
References
1. American Diabetes Association. Standards of medical care in diabetes--2011.Diabetes Care. 2011 Jan;34Suppl 1:S11-61.
2.Diabetic Retinopathy Clinical Research Network (DRCR.net), Beck RW, Edwards AR, Aiello LP, Bressler NM, Ferris F, Glassman AR, et al. Three-year follow-up of a randomized trial comparing focal/grid photocoagulation and intravitreal triamcinolone for diabetic macular edema. Arch Ophthalmol. 2009;127:245-251
3. HARRISON’S PRINCIPLES OFInternal Medicine16th Edition
4.Juvenile Diabetes Research Foundation International 120 Wall StreetNew York, NY 10005–40011–800–533–CURE (2873).
5.National Diabetes Information Clearinghouse 1 Information WayBethesda, MD 20892–35601–800–860–8747301–654–3327
6. O'Doherty M, Dooley I, Hickey-Dwyer M. Interventions for diabetic macular oedema: a systematic review of the literature. Br J Opthalmol. 2008;92:1581-1590.
