Saturday, December 25, 2010

INDIAN CORNEAS:CENTRAL CORNEAL THICKNESS

Studies done on Indian eyes at Sankara Netralaya,Chennai and Suraj Eye Institute,Nagpur showed the following results:

The mean CCT for the South Indian adult population was 511.4+/-33.5 microm, and CCT in males (515.6+/-33.8 microm) was significantly (P = 0.0001) greater than females (508.0+/-32.8 microm). The CCT was significantly greater (by 18 microm) in the urban population and decreased with age in both genders (P<0.0001).
Among Indian subjects from Central India the mean CCT was 514+/-33 microm (median, 517 microm; range, 290-696 microm).Central corneal thickness and steepness of the anterior corneal surface may thus both have to be taken into account when applanation tonometry is performed the study concludes.
Thus these studies have implications on the diagnosis and management of Glaucoma.

Thursday, August 5, 2010

STEM CELL RESEARCH & THE EYE

According to ISSCR, Stem cell research is a evolving technology that takes primitive human cells and develops them into most any of the 220 varieties of cells in the human body, including blood cells,brain cells,eye,etc
Stem cells have two properties. First, they can ‘self-renew,’ that is they can divide and give rise to more stem cells of the same kind. Second, they can mature or ‘differentiate’ into specialized cells that carry out a specific function, such as in the skin, muscle, or blood
A stem cell therapy is a treatment.This utilises stem cells, to replace or to repair a patient’s cells or tissues that are damaged. The stem cells might be put into the blood, or transplanted into the damaged tissue directly, or even recruited from the patient’s own tissues for self-repair.
Blood stem cells by bone marrow transplant is being done more than 50 years, and advanced techniques for collecting blood stem cells are now used clinically. Umbilical cord blood, like bone marrow, is often collected as a source of blood stem cells and is being used experimentally as an alternative to bone marrow in transplantation.
A few years ago, Dr. Funderburgh and other University of Pittsburgh researchers identified stem cells in a layer of the cornea called the stroma.The US team took stem cells from human corneas and implanted them into the eyes of partially blind mice who were missing a structural protein.
Three months after treatment with the cells, the cloudiness was gone and their corneas were as transparent as those of normal mice.
We look forward to more good news from Stem Cell therapy.So keep watching this space for more and more news on Stem Cell therapy in the Eye.

Tuesday, July 27, 2010

GROWING RESISTANCE TO OCULAR ANTI-BIOTICS

Eye bacterial infections include conjunctivitis,keratitis, endophthalmitis,preseptal cellulitis,orbital cellulitis, and dacryocystitis.Broad spectrum antibiotics are the choice of treatment.These are effective against the most common bacteria associated with these ocular infections. However, the widespread use of broad-spectrum systemic antibiotics has resulted in resistance among both Gram-positive and Gram-negative bacteria to a number of the older antibiotics used to treat ophthalmic infections.

A recently published study from India has shown a link between in vitro resistance and clinical failure to respond in patients with keratitis caused by Pseudomonas isolates. Garg et al(Ophthalmology 1999;106:1319-2)reported that of 141 culture-proven cases of Pseudomonas keratitis, 22 cases were caused by isolates resistant to ciprofloxacin (mean MIC 43mg/ml). Of the 19 (of 22) cases treated initially with ciprofloxacin, 15 (76.7 per cent) worsened or showed no clinical improvement after three days of intensive therapy and required modification of antibiotic therapy, corneal grafting or evisceration (surgical removal of the contents of the eyeball).

Broad-spectrum, bactericidal antibiotics and its resistance is becoming a greater problem in managing ocular bacterial infections.The fourth-generation fluoroquinolones with broader gram-positive coverage and greater effectiveness against emerging resistant isolates are now available for ophthalmic use.

Sunday, July 25, 2010

EMERGENCY EYE CARE:CHEMICAL INJURIES

If a chemical gets in your eye,we generally close our eyes or rub it. However, this could cause more irritation. Immediately rinse your eye under a steady stream of clean warm water for 15 minutes


Randleman et al (2009) Emory Eye centre states that chemical injuries account for around 7% of work-related eye injuries treated at US hospital emergency departments. Furthermore, they said that over 60% of chemical injuries occur in the workplace, 30% at home and 10% as a result of assault.

Acids are chemicals that aren't extremely dangerous, even though they may initially sting and cause redness. Alkalis, like oven cleaners or toilet bowl cleaners, although they may not hurt at first, can cause serious damage, including vision loss and blindness

Common sources of alkali are as follows:Cleaning products,Fertilizers,Drain cleaners,Cement, plaster, mortar (eg, lime),Airbag rupture (eg, sodium hydroxide)Fireworks (eg, magnesium hydroxide),Potash (eg, potassium hydroxide)
Common sources of acids are Battery acid (eg, sulfuric acid),Bleach (eg, sulfurous acid),Glass polish,Vinegar (eg, acetic acid),Chromic acid,Nitric acid,Hydrochloric


If available, the eye should be anesthetized prior to irrigation.
Ideally, the eye should be irrigated with a sterile balanced buffered solution, such as normal saline solution or Ringer's lactate solution. However, immediate irrigation with even plain tap water is preferred without waiting for the ideal fluid.
The irrigation solution must contact the ocular surface.Irrigation should be continued until the pH of the ocular surface is neutralized, usually requiring 1-2 liters of fluid
Chemically injured eyes have a tendency to poorly produce adequate tears; therefore, artificial tear supplements play an important role in healing.
A therapeutic bandage contact lens until the epithelium has regenerated can be helpful in some patients.

Refer the patient to the Ophthalmologist (Eye Specialist) at the earliest.

Monday, March 8, 2010

NEWER EYE DRUGS FOR GLAUCOMA: RESEARCH AHEAD

A study published in the peer-reviewed medical journal Proceedings of the National Academy of Sciences,and conducted by Dr Alessandro Lambiase and colleagues from the University of Rome, the National Research Council, the Gian Battista Bietti Eye Foundation and the European Brain Research Institute.

Investigations were done on the application of nerve growth factor (NGF) on visual symptoms of glaucoma.NGF are proteins that play a role in the survival of nerve cells. Use of this appears to prevent, and even reverse, glaucoma’s characteristic pressure damage to the eyeballs of both rats and humans. This small study has encouraging findings, with humans experiencing improvements in visual clarity and contrast. Two of the patients showed an improvement in their visual field too. However, with only three subjects the study is too small to draw concrete conclusions.Research like this is usually followed by more investigations on potential new treatments, and only the results of long-term, randomised controlled trials will provide definitive answers about the potential benefits of using NGF eye drops.

More details: www.nhs.uk/news/2009/08August/Pages/GlaucomaEyeDropCure.aspx

Sunday, March 7, 2010

NEWER EYE MEDICATIONS: DIABETIC RETINOPATHY,EYE ALLERGY....

In DIABETES, a journal by the American Diabetes Association the role of Topical Administration of Nepafenac showed Inhibition of Diabetes-Induced Retinal Microvascular Disease and Underlying Abnormalities of Retinal Metabolism and Physiology.Professor Timothy S. Kern noted pharmacologic treatment of diabetic retinopathy via topical Nepafenac, an anti-inflammatory drug known to reach the retina when administered via eyedrops, on the development of early stages of diabetic retinopathy and on metabolic and physiologic abnormalities that contribute to the retinal disease.

Topical antihistamines & decongestants
Eye allergy drugs or Antihistamine eyedrops work by blocking histamine receptors in the conjunctiva. The histamine, therefore, is unable to attach to the conjunctiva and exert its effects. They are effective in relieving itching but have little impact on swelling or redness. They have advantages over antihistamine tablets; there is a faster onset of action and less drying of the eye. The new generation of topical antihistamines includes emedastine difumarate (Emadine) and levocabastine (Livostin). Patanol, a topical mast-cell stabilizer, is a safe, highly effective, long-acting treatment.). Side effects of few combination antihistamine-decongestant preparations are minimal, but the drops may become less effective if used for prolonged periods. They do have a potential for abuse and should not be used by people with narrow-angle glaucoma.