We all probably know of senior citizens who have undergone cataract surgery. It is one of the common ocular conditions one hears of from older parents, their friends and our elderly relations. As lay persons we may not know that cataract may be caused by a number of reasons and has different presentations in people. Let’s take a look at what age-related/senile cataract is, the types of age-related cataracts, and the causes of this ocular condition.
Senile cataract starts out with the mild opacity--or loss of transparency and clouding--of the optical lens, gradually progressing to thickening or swelling of the lens, concluding with the shrinkage of the lens and complete loss of transparency, if gone untreated.
Depending upon the extent of damage to the eye lens, senile cataract is classified as:
• Immature senile cataract
At this stage the eye lens begins to become opaque and the optic disc view is hazy. The cortex remains clear. It is an incomplete cataract.
• Mature senile cataract
At this stage of cataract, the lens has thickened with protein deposition and there is total opacity of the entire lens. There is no disc view.
• Hyper-mature senile cataract
This is also known as Morgagnian cataract. By now, the whole lens capsule has shrunk and the contents have turned solid and wrinkled or soft and liquid. In most cases, the cortical matter is liquefied.
Senile cataract may also affect the center of the lens known as the nucleus. Senile nuclear cataract is yet another classification where the nucleus may present opacity of a specific color. The hardening of the nucleus occurs rather gradually. A person can detect the start of the process as they see glare and halos on or around objects they see. (Source: Livestrong.com; Article Title: Types of Senile Cataract; Author: Suzanne Robin; Last Updated: 2nd February, 2010; URL: http://www.livestrong.com/article/78866-types-senile-cataracts/). It may progress to loss of contrast in colors--especially identification of difference between dark blue and black and between blues and purples--that they see and eventually result in the development of hazy vision.
• Nucleus causing brown opacity is referred to as cataracta brunescens or brown cataract. It is one of the most difficult types of senile nuclear contracts to remove by operation due to the hardening of the lens.
• Senile nuclear cataract with black opacity is referred to as cataracta nigra or black cataract. Like brown cataract, the lens in this stage has become quite hard and presents challenges to the doctors performing a surgical removal of the deposition.
• Nuclear cataract condition presenting amber opacity is called cataracta rubra
• Yellow nuclear cataract is the deposition which has not hardened a lot and is relatively easy to remove surgically.
Cortical cataracts occur in the cortex of the eye. This means they are located outside the eye lens. They have a spoke-like presentation – growing from the outside of the lens inward to the center towards the optic disc. When mature, the cortical cataracts make the lens look white. Cortical cataracts are brought on by long exposure to intense sunlight and diabetes.
There is also the posterior subscapular cataract type but it is not very usual among the older population. The cataract begins as a small opacity within the capsule, at the back of the lens. It occurs on the membrane that surrounds the lens. Unlike other cataracts, the posterior subscapular cataract progresses rapidly and matures faster. A person may suspect the presence of this cataract when they experience trouble reading, or driving in the face of headlight glare at night.
The causes of senile cataract could be any or a combination of the following factors:
• Exposure to radiation from outer space (especially in case of commercial pilots)
• Long term exposure to UV lights
• Exposure to microwave radiation
• Iodine deficiency
• Heredity
• Eye injury and physical trauma
• Allergies of the eye
• Long-term usage of corticosteroids and drugs containing the chemical Quetiapine
• Hypertension
• Diabetes
• Smoking
• Obesity
(Source: Mayo Clinic; Report Tile: Cataracts; Page Title: Risk Factors; Author(s): Mayo Clinic Staff; Last Updated: April 2010; URL: http://www.mayoclinic.com/health/cataracts/DS00050/DSECTION=risk-factors)
1. Brown Cataract - (Source: Innvista; Report Title: Page: Types of Cataract; URL:http://www.innvista.com/health/ailments/eyeail/cataract.htm)
2. Black Cataract - (Source: Wikipedia; Article Title: Cataract/Classification ; URL:http://en.wikipedia.org/wiki/Cataract)
3.Cataract Rubra - (Source: Frank Hospital Workshop; Report Title: Cataract; Page 3,4 - Classification; URL:http://frankshospitalworkshop.com/equipment/documents/ophthalmic/wikiped...)
Reviewed June 8, 2011
INFORMATION IN THIS ARTICLE IS NOT MEDICAL ADVICE. ALL INFORMATION GIVEN IS TO BE CHECKED WITH YOUR DOCTOR BEFORE IMPLEMENTING OR TAKING THEM AS STANDARD OR VERIFIED.
Mamta Singh is a published author of the books Migraines for the Informed Woman (Publisher: Rupa & Co. URL: http://www.amazon.com/Migraines-Informed-Woman-Tips-Sufferer/dp/8129115174/ref=sr_1_2?ie=UTF8&s=books&qid=1298990756&sr=1-2), the upcoming Rev Up Your Life! (Publisher: Hay House India) and Mentor Your Mind (Publisher: Sterling Publishers). She is also a seasoned business, creative and academic writer. She is a certified fitness instructor, personal trainer & sports nutritionist through IFA, Florida USA. Mamta is an NCFE-certified Holistic Health Therapist SAC Dip U.K. She is the lead writer and holds Expert Author status in many well-received health, fitness and nutrition sites. She runs her own popular blogs on migraines in women and holistic health. Mamta holds a double Master's Degree in Commerce and Business. She is a registered practitioner with the UN recognised Art of Living Foundation. Please visit www.mamtasingh.com
Edited by Alison Stanton