Articles on vision

Do You Have 20/20 Vision ?

Dr. Charu Tyagi, Ophthalmologist
Visual Acuity: What is 20/20 Vision?20/20 vision is a term used to express normal visual acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance. If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet.Having 20/20 vision does not necessarily mean you have perfect vision. 20/20 vision only indicates the sharpness or clarity of vision at a distance. Other important vision skills, including peripheral awareness or side vision, eye coordination, depth perception, focusing ability and color vision, contribute to your overall visual ability.Neural factors that limit acuity are located in the retina or the brain (or the pathway leading there). Some people can see well at a distance but are unable to bring nearer objects into focus. This condition can be caused by hyperopia (farsightedness) or presbyopia (loss of focusing ability). Others can see items that are close but cannot see those far away. This condition may be caused by myopia (nearsightedness).A comprehensive eye examination by a eye  doctor  can diagnose what is affecting your ability to see well. In most cases, your ophthalmologist can prescribe glasses, contact lenses or a vision therapy program that will help improve your vision. If the reduced vision is due to an eye disease, you may be prescribed ocular medication or another treatment.MYTH: Having 20/20 vision means that the eyes are perfect.FACT: The term "20/20" denotes a person with excellent central vision. But other types of vision-such as side vision, night vision, or color vision might be imperfect. Some potentially blinding eye disease, such as glaucoma or diabetic retinopathy, can take years to develop. During this time, they are harming parts of the inner eye, but the central vision can remain unaffected.

Computer Vision Syndrome: Time to Wake Up Your Tired Eyes

Mr. Md. Oliullah Abdal, Optometrist
Computer Vision Syndrome (CVS) also called Digital Eye Strain,describes a group of eye and Binocular vision related problems that result from prolonged laptop, tablet, e-readers and mobile phones use. Several people experience eye discomfort and vision issues when seeing digital screens for extended periods. The level of discomfort seems to extend with the amount of digital screen use.More individuals are progressively getting dependent on computers in their everyday routine and this has brought  various well-being concerns like ocular discomfort, muscular strain and stress.CVS affects most people who work for over 3 hours a day in front of the computer screen, particularly youngsters and grown-ups above 40 years old.Symptoms of Computer Vision SyndromeThe degree to which people experience visual symptoms often depends on quality of their visual abilities, binocular vision functions and the amount of time spent looking at a computer screen.Uncorrected vision problems like astigmatism, farsightedness, inadequate eye focusing or eye coordination abilities, and aging changes of the eyes, such aspresbyopia, would all be able to add to the development of visual symptoms when using a computer or digital screen device.Common symptoms associated with Computer Vision Syndrome (CVS) are Blurred VisionBurning of eyes Neck/Shoulder pain Eyestrain and FatigueHeadachesIrritation and redness of eyesCauses of Computer Vision SyndromeThere are various components that determine the amount of strain your body feels as you work on a PC or other advanced gadgets, incorporating distance from the screen, lightening in the room, seating posture, glare on the screen and angle of your head. One of these may consolidate to bring about an uncomfortable amount of strain on your eyes.Some other includesBinocular vision function abnormalityInfrequent blinking Wrong work place ergonomics Presbyopia or Bifocal GlassesTreatment for Computer Vision SyndromeUse of artificial tears to cure dry eyesWearing right power glasses Vision Therapy to improve convergence and other binocular eye problems Vision Therapy includes a variety of activities using gadgets like prisms, lenses and computerised programs. This can help patients to develop or enhance visual comfort, as, fundamental visual skills and abilities and efficiency. Common tips for reducing or even preventing the effects of Computer Vision SyndromeEnsure the lighting in the room is comfortable on the eyes, and keeps you from gazing into glare on the computer screen Position the digital devices so that your head is in a normally comfortable position while using 20-20-20 rule - Every 20 minutes, take a 20-second break and focus your eyes on something at least 20 feet away to relax your eyesEnsure your seat is comfortable. A comfortable seat with backing for your neck and back will help you keep away from neck and shoulder strain usually connected with computer vision syndrome.

Refractive Errors In Children

Dr. Brijinder Singh Rana, Ophthalmologist
Refractive error is the most common cause of visual impairment in children. Visual impairment can have a significant impact on a child’s life in terms of education and development. It is important that effective strategies be developed to eliminate this easily treated cause of visual impairment.Children with such errorsFind difficulty in reading, writing and have difficulty to see distanceEye strain while reading for long or shrink eyes to see at a distanceMay have squint (crossed eyes)May hold book close while readingIn addition to the above condition,Child may rub the eyes or blink frequentlyHeadache in forehead regionRecurrent swelling in the eyelidsCorrection using the spectacles is the best option available .Though children may initially refuse to accept glasses, They will become fond of them once they realize they can see better with them on. The power of glasses may change depending on the growth of eyeballs. An eye checkup and change of glasses if necessary, has to be done once six months for children less than 5 years of age and once a year thereafter.Making a child wear glasses regularly is the duty and responsibility of the parents. Failure to wear glasses in childhood will retard the development of vision in that eye. Children older than 15 years can use contact lenses, if they don’t want spectacles. Those over 18 years of age with stable power have option of going in for lasik.“HELP YOUR CHILD SEE THE WORLD BETTER.WEARING GLASSES IS NOT A STIGMA”

"Oh God! I Have Been Diagnosed with Cataract!"

Dr. Manoj Rai Mehta, Ophthalmologist
When a patient is diagnosed to have cataract the following questions pop up immediately:Is it unusual at this age?Can it be cured with medication of any sort?Is the surgery a must?  What if I do not get operated?How long can the surgery be avoided?  Cataract is the commonest cause of gradual, painless, progressive diminution of vision in middle-aged and old people.  The reaction of a patient varies from utter shock, disbelief to acceptance and discussion of further treatment.Why Me?     While cataract is known to occur at all ages and even congenitally, it is the senile, age-related, a cataract that is the commonest in prevalence.  People get cataract at different ages depending upon familial trends and associated systemic illnesses and exposure to certain light frequencies.  Diabetes (and other metabolic afflictions), steroid intake and exposure to Ultra Violet light cause early cataract formation.  Trauma to the eye also causes cataract formation. Why does vision decrease?The normally transparent crystalline lens of the eye becomes translucent and some areas turn opaque, thus causing scattering of light as well as a blockage.  Location of opaque areas also matters as central changes affect vision much earlier than those in the periphery.  Opaque areas close to the nodal point of the lens will affect vision profoundly even if small in size.Is there a medical cure available?In spite of tall claims no medical treatment has been established scientifically beyond doubt till now. Anecdotal claims do not satisfy scientific hypothesis.  Use of antioxidants may retard the progression of cataract as a general anti ageing effect.  Avoid using eye drops of unknown composition and dubious sources in the name of magical cures!  They may cause more harm than benefit.What is the "Right Time" for surgery?It depends on upon the lifestyle, profession and visual needs of a patient.  It is ordinarily an elective surgery and a patient should discuss all the elements of procedure and care with the surgeon and decide on the timing of surgery.  Surgery is aimed at improving "quality of life".  Glare, difficulty in driving and reading are some of the things that can affect the quality of life of a person and surgery is expected to alleviate them.  A driver, an IT professional, an avid golfer may choose to undergo surgery at an earlier stage than a person who does not drive and read much.Gone are the days when patients used to wait for the cataract to mature! Surgery time is decided after a mutual discussion on outcomes and QOL targets.  Surgery should not be postponed for long in case of advanced cataracts as they turn harder with time and surgery becomes more challenging. There are situations when surgery can not be postponed such as a swollen lens causing a rise in pressure or a leaky lens causing inflammation.Cataract surgery is one of the most gratifying surgical procedures and safest as well.  Do not get scared, discuss the goals of surgery and take a cool decision.   

Amblyopia (Lazy Eye ) Management With Vision Vision Therapy - a Paradigm Shift !

Mr. Md. Oliullah Abdal, Optometrist
Amblyopia - Kanohi Vision Therapy CentreLazy eye or AmblyopiaAmblyopia is commonly known as lazy eye. Amblyopia means poor vision in an eye that could not develop normal sight during childhood. This can happen in both the eyes as well.If the brain has not received clear images from the weak eye, it starts neglecting this eye. The eye is then said to be amblyopic or lazy as vision does not develop to its potential. Common causes of Amblyopia Refractive errors such as short sightedness, long sightedness or astigmatismLarge difference in spectacle powers between the two eyesStrabismus or squintObstruction or deprivation of vision by droopy eyelid, cataract, any corneal opacity or other eye diseases.ManagementSuccessful treatment depends on how severe the Amblyopia is and the onset of deprivation of vision.Refractive Error Correction Proper spectacle correction to be worn at all times. People can opt for other modalities like Contact Lenses, LASIK or ICL (Implantable Intra Ocular Contact Lens). Pharmacological treatment Sometimes we prescribe some medications to help the amblyopic eye see. Vision therapy Individualized computerized programmes, sometimes with the help of prisms or special lenses are aimed to remove the suppression in the brain towards the lazy eye and enable the brain to acknowledge impulses sent to it from that eye. Advantages of vision therapy in the treatment of Amblyopia Works on both eyes, so develops binocular vision and 3D or stereo vision.Helps in adult Amblyopia reversal.Shorter treatment time span or quicker rehabilitation.Longer retention or no regression.Better compliance and acceptance.

Exercises Which Will Improve Your Vision

Ms. Swati Kapoor, Dietitian/Nutritionist
Many of us are proactive about our dental hygiene but are we worried about our eye health with strong determination? Lot of us spend countless hours in our workplace, by sitting on the desk and staring at our computers, so maintaining a healthy eye becomes mandatory. There are many ways by which you can do so - eat right, take adequate sleep, combat with stress, meditate and do some exercise.By doing eye exercises, one experiences tremendous benefits such as increase in eye muscle strength, better focus and better eye movement. But those who have serious problems can always consult a doctor for better solution.Let’s scroll down and implement these exercises for better eye health:1. The Eye RollSlowly move your eyes in circular motion, clockwiseRepeat it 5 timesSwitch direction and rotate eyes in anticlockwise directionRepeat it 5 times2. The Eye PressPress the tips of several fingers against your upper eyelids using light pressure.Press for 2 secondsRelease your fingersRepeat 10 times3. The Eye raiseSlowly raise your eyes until you are looking as far up as possible.Hold for five seconds.Slowly lower your eyes until you are looking as far down as possible.Hold for five seconds.Return your eyes to center.Repeat 10 times.4. The Wide EyeFacing straight ahead, squint your eyes as much as possible.Hold this squint for five seconds.Open your eyes as wide as possible.Hold this for five seconds.Repeat 10 times.

'Computer' Vision Syndrome? But I Do Not Work on a Computer!

Dr. Manoj Rai Mehta, Ophthalmologist
Computer Vision Syndrome (CVS) is now recognised as an "occupational illness" that afflicts people working on computer screens for extended hours of time.  With the advent of "smart phones" the screen has shrunk in size and the CVS has assumed proportions of a "Pandemic" and is no longer restricted to IT professionals alone!  Let us try to establish a connection between different variables that interact in this complex situation:Screen size and illumination vary from flat screen monitors to laptops to tablets to smart phones.  Background illumination.   Font size is variable to a significant extent as also the background colour and contrast.There are pictures, movie clips, animation clips, geometrical designs of different shapes that need quick processing by brain.Ergonomics of an office/work place or household.Posture.   The distance at which a screen is held. From office the CVS has invaded households and now every family member is at risk including household helpers!  Thus CVS is caused by interaction of several factors- small screen, small font size, fast moving images on a small screen, strong illumination of screen, bad posture, poor background illumination.  A smart phone can be carried any where and young adults who get hitched to it can carry it to their bed and peer at the screen without regular blinking in any posture, close to face for an indefinite time.Symptoms of CVS are non specific but nagging and annoying: Watering of eyes, irritation, burning sensation, brow-ache, headache, deep ache in the head, tiredness, lack of freshness, redness of eyes etc.  There are posture related symptoms also such as neck stiffness, pain in the neck, back stiffness and pain etc.All the symptoms are exaggerated by lack of quality sleep, inadequate rest, lack of breaks during work, anxiety etc.Management is simple-ergonomic setting up of computer screens/laptops in the offices.  Periodic breaks for relaxation.  Open areas in offices for fresh air and relaxation from focusing at near distance.  Lubrication of eyes with preservative free artificial tear eye drops, rolling of eyes and blinking completely a couple of times.  Stretching exercises for neck and back under supervision.  Avoid smoking and excessive consumption of tea/coffee under misconception of freshening up. Watching television or a movie after a long day is no relaxation for eyes, in fact it is additional stress.  Play outdoor games instead. Tablets and smart phones use should be curtailed, at least for watching movies, serials, matches etc.  Increase font size for a comfortable reading.  Do not take tablets and mobiles to bed and keep them away from bedside for charging as well.    Good habits, disciplined life style with regular exercise and balanced diet helps in keeping CVS away.   

How Do I Behave When I Am Undergoing Cataract Surgery?

Dr. Manoj Rai Mehta, Ophthalmologist
Cataract Surgery nowadays is usually performed under 'topical anaesthesia' that involves instillation of drops of the anaesthetic agent on the eye surface.  The patient retains the power to close the lids and move the eyeball during surgery, feel no pain but touch and pressure sensations are unaffected.  A peribulbar block anaesthesia may be used at times on surgeon's discretion that involves an injection of anaesthetic agent around the eyeball with a short needle.  This takes away lid and eye movements to a large extent but some control may remain with the patient.     Operating Surgeon expects the patient to follow the instructions for a smooth surgery.  It is important to have a surgical counselling session with the doctor to understand the procedure and expected sounds/conversation during the operative procedure.  The sequence of events should be understood and played in your mind while you move through the surgical suite.You should be wearing loose, comfortable hospital pyjama suit.  Do not hesitate to change it if it is tight around your neck.  Some hospitals have the policy to allow you to wear your own loose clothes and give you a hospital gown over them.  Please ensure you are not wearing tight fitting clothes and your neck is free.  Ladies to tie their hair in a ponytail with a band or a soft bun with no clips or claspsSit quietly in the pre-operative area and use the washrooms before going to the OR.  You may take sips of water if your mouth feels dry but do not hydrate yourself too much.You may be given a cap and eye marked for surgery.  The antiseptic solution will be painted around the eye.  Let the solution dry and do not touch your eye. OR assistant will help you lie down on the OT table with a rubber ring under the head to prevent rolling from side to side. You should be comfortable and be able to breathe rhythmically while lying down.  Ask for a head raise if neck extension is hurting you and get the ring adjusted to your comfort and if it is hard for you to ask for a softer ring.When you are comfortable allow the staff to put monitoring devices which could be a pulse oxygen meter alone or additional cardiac electrodes.  Breath rhythmically and try to relax.Sterile Drapes will be placed around your head and an adhesive eye drape on the eye to be operated upon.  Please maintain your head in a position as required and adjusted by the surgeon.  Do not move your head or lower your chin.  The surgeon works under a microscope and any movement shifts the focus and obstructs in smooth surgery.There will be several sounds in the OR that you should ignore-beep of monitors, hum of air circulation unit, trolley wheels, the doctor would be giving instructions to staff and asking for instruments etc.  Try to keep your attention focused towards surgery only.Coughing and snorting during surgery can create complications, always ask the surgeon to stop the surgery if you feel like doing so.  Do not try to suppress a cough or sneeze by holding breath.  Do not bear down or move.Follow instructions of a surgeon and do not start a conversation. Answer only when a question is directed towards you.  The surgeon may ask you to look in a particular direction.  You have to follow the command by moving your eyes and not head unless the specific instruction is made. The first touch of the instrument will increase your confidence.  Do not wince, squeeze your lids or make a jerky movement if you feel some pain.  Inform the doctor, who will reinforce anaesthesia.Cataract Surgery machines also produce different types of sounds during different phases of surgery and also have synthesised verbal outputs.  Do not get distracted by the same.You will see movements in front of the eye during surgery and also perceive vibrations.  Light intensity will increase towards the end of surgery.  A calm patient who is having a regular rhythmic breathing and a regular normal pulse rate makes a surgeon's job easy.(In case of specific problems additional monitoring and specialised anaesthetic cover may be required which the operating surgeon will discuss before hand).               

Computer Vision Syndrome

Dr. Sridevi Haldar, Ophthalmologist
It’s a truly twenty first century disease. Its a technology driven rising health concern issue. With the increasing use of computer display screens, CVS is inevitable and unavoidable. Frequently fluctuating or blurring of vision, tired eyes, eyestrain, redness are some of the most commonly experienced symptoms of computer vision syndrome.What Causes Computer Vision Syndrome?CVSis caused by our eyes and brain reacting differently to characters on a computer screen then they do it to printed characters. Our eyes have little problem focusing on printed material that has dense black characters with well defined edges. But characters on a computer screen don’t have the same degree of contrast definition.Words on a computer screen are created by combinations of tiny points of light (pixels) which brightest at the centre and diminish in intensity towards their edges. This makes it more difficult for our eyes to maintain focus on these images. Instead, our eyes want to drift to a reduced level of focusing called resting point of accommodation, RPA. Our eyes unwillingly move to the RPA and then strain to recover focus on the screen.This non-stop flexing of the eyes and focusing the muscles creates fatigue and eye strain that commonly occurs during and after computer use. Another cause is reduced blinking. When we look at the computer screen we tend to blink less than what we should. This leads to burning of eyes and burning, itching, etc.Symptoms of computer vision syndrome If one spends more than 2hrs/day in front of a computer screen, its likely that he will experience some degree of CVS.Symptoms of CVS include headache, loss of focus, burning eyes, tired eyes,double vision, blurred vision, neck and shoulder pain.How does your vision affect your body?As you age your eyes will develop a condition called presbyopia. This means for people in their 40’s or older, the computer screen gets a little fuzzy even with glasses. Trying to read a fuzzy screen can give you a headache.Where do the other aches and pains come in?They are often caused by trying to read the screen through the bottom portion of bifocals or through half-reading glasses. You tip your head up or lean forward to see and this unnatural makes you sore.How to prevent CVS?To reduce your risk of computer eye strain and computer vision syndrome, consult an eye care professional who specializes in computer vision care. Use of antiglare screens,computer eye glasses (multifocallenses, single vision lenses, tinted glasses), postural adjustment can reduce computer  related eye strain effectively and increase computer work productivity.Computer glasses: Need or necessity  When studies suggesting that most computer users experience some level of eye discomfort from computer work, it’s reasonable to say that most people who work on a computer more than a couple hours daily could benefit from computer eyewear with the correct prescription.10 steps for relief:Get eye test done.Blink your eyes more often and keep them lubricated.Exercise your eyes by looking away from the computer every 20 minutes at 20 feet distance for 20 secondsTake frequent breaks.If you wear progressive or bifocal lenses position your screen lower in relation to your eyes.Position the top of the monitor just below a level horizontal with your eyes. Tilt the top of the screen away from you at 10-20 degree angle. Use proper lighting. Minimize glare on your screen.Upgrade your display-use a LCD screen.Adjust the brightness and contrast of your computer screen to be same as your work environment.

Getting Clear About Cataracts: Causes, Symptoms and Prevention

Dr. Somdutt Prasad, Ophthalmologist
Growing old is a wonderful thing, if you embrace it. You can celebrate several things about it- strikingly steely hair, mature and classy look and elegant persona. Sure, there are challenges like aches and pains, but these can be managed with a few lifestyle changes and necessary medical assistance. Bigger things in life can always be dealt with, but sometimes the smallest of things can cause big problems in your advanced years. And, cataracts are one of those things! Causes of Cataract Cataracts are clouding of the eye’s lens, which impairs vision leading to blindness in old age. There are various causes for developing cataract, and the most common cause is build up of protein in the eye, which prevents light from passing through the lens, leading to blurred vision in old age. Genetic history, eye injury and inflammation, diabetes, hypertension and exposure to direct sunlight for long hours are some of the other causes for this condition. Cataracts usually form very slowly through the years, and you might not notice it until it starts blocking your vision considerably.People with cataract will experience some of these symptoms:Unclear vision, something like looking through an old cloudy glass or frosted glassCloudy vision with spots, dots or patchesBad eyesight when the light is dim or during the nightImpaired vision on bright daysDifficulty in readingUnclear vision even with glasses onSeeing a halo around bright objects, such as vehicle headlights or road lightsSome people also experience double vision in one of the eyesCataracts cannot completely be prevented; however, you can reduce the risk of developing it in later stages by adopting the following steps-Say no to smoking: Some studies suggest that people who smoke develop cataract more that those do not smoke. Smoking not only increases your chances of developing cataract, but also increases the risk of other eye related diseases.Nutritious food: Include lots of green vegetables, fruits, whole grains, plant/lean meat proteins and carbohydrates to your diet. This reduces your chances of getting cataract early in life.Stay away from direct sunlight: The UV radiations from the sun can harm your eyes, leading to cataracts. Protect your eyes by wearing sunglasses when out in the sun.Diabetes: If you have diabetes, take your medication and keep blood sugar level in control. People with diabetes are at a higher risk of getting cataract.Don’t let cataracts creep up on you and steal your colours. Get yearly eye checkups done, take necessary precautions and live life to the fullest!