Tests

Because most eye disorders are symptomless in their early stages, many people are unaware that they have one. Surveys by researchers at Johns Hopkins have found that about one third of people with eye disease were unaware of it and that more than one third of those ages 65 to 84 had not visited an ophthalmologist (eye doctor) in the past year. Periodic visits to an eye care specialist are needed to detect conditions early enough to allow effective treatment. Regular checkups are particularly important for people over age 65, those with risk factors for serious eye disease, those in fair or poor general health, and those with diabetes.

Choose another disease or condition... Allergic Rhinitis Allergies, Food Allergy & Asthma Center Alzheimer's Disease Anxiety Aortic Aneurysms Arrhythmia Arthritis, Osteo- (OA) Arthritis, Rheumatoid (RA) Asthma Atopic Dermatitis Attention Deficit Hyperactivity Disorder (ADHD) Back Pain Brain Tumor Bones, Joints & Muscles Center Breast Cancer Brain & Behavior Center Brain Tumor Cancer Center    Brain Tumor    Breast Cancer    Cancer Prevention    Clinical Trials    Colorectal Cancer    Endometrial Cancer    Living With and Beyond Cancer    Lung Cancer    Prostate Cancer    Skin Cancer Cardiomyopathy Cataracts Cholesterol Control Clinical Trials Chronic Obstructive Pulmonary Disease (COPD) Colorectal Cancer Congenital Heart Disease Congestive Heart Failure (CHF) Coronary Artery Disease (CAD) Crohn's Disease Depression Diabetes Center Diabetes, Type 1 Diabetes, Type 2 Digestive Disorders Center Eczema Endometrial Cancer Erectile Dysfunction (ED) Eye & Vision Center Fibromyalgia Food Allergies Gallstone Disease Gastroesophageal Reflux Disease (GERD) GERD Glaucoma Hay Fever Headache Heart Center Hepatitis A Hepatitis B Hepatitis C High Blood Pressure Hypertension Hypertrophic Cardiomyopathy (HCM) Impotence Insomnia Irritable Bowel Syndrome (IBS) Living With and Beyond Cancer Losing Weight Lung Cancer Macular Degeneration Memory Loss Osteoarthritis (OA) Osteoporosis Parkinson's Disease Peptic Ulcer Prediabetes Prostate Cancer Respiratory Disorders Center Restless Legs Syndrome (RLS) Rheumatoid Arthritis (RA) Sexual & Reproductive Health Center Sinusitis Skin Cancer Sleep Apnea Sleep Center Stroke Type 1 Diabetes Type 2 Diabetes Ulcerative Colitis (UC) Weight Control Get more information online about cataracts See our in-depth guide on glaucoma More on eyes in our Eye and Vision Center Cataracts-Related Clinical Trials Information Email this page Print this section

Before cataract surgery, the ophthalmologist will obtain a medical history, which includes past and current medical conditions, current medications, and allergies. A-scan ultrasonography, a test that uses sound waves or a laser to measure the length of the eyeball, is routinely performed. The eyeball length is used to determine the appropriate focusing power of the intraocular lens implant, a plastic lens that replaces the lens removed during cataract surgery. If the surgeon cannot see the retina in the back of the eye because the cataract is too opaque, another test called B-scan ultrasonography is used. This test uses reflected sound waves to look at structures in the back of the eye.