Front Sight

19 03 2014

I love to shoot firearms!  There is something about shooting a pistol, rifle or shotgun that gets in your blood.  It’s exciting, challenging, requires control, discipline and focus.  It is part of our American culture and my family history.   I personally believe everyone should know how to shoot to protect their family and our country.   It is safe if you always treat the firearm with respect and always obey the rules of firearm safety.   Fear of firearms is overcome by knowledge and training, just like learning to drive.

As I enter into the age of “the arms getting shorter” stage or what is known as “presbyopia”, I am becoming more acutely aware how much more difficult it is to shoot with traditional, open (no magnification with a scope)  iron sights on the firearm.

In our forties, the crystalline lens of the eye reaches the stage where it hardens and loses it’s elasticity.  When this happens, the lens of the eye can’t change shape much to help focus on near objects.  The focusing muscle doesn’t weaken, the lens just can’t flex and change shape.  Like a pair of binoculars that has the focusing knob rusted up so you can only see far away.

Pistol shooting is affected the most due to the short distance of the sights from the eye.  Since the eye can only focus at one place at any given time, the key to shooting well with pistols is to concentrate on the front sight.  The rear sight will be blurred some and the target will be blurred some but the front sight is the most critical to focus on.   Especially if you train more realistically to move and shoot.   To “get off the X”  as they say.

 

Glasses are problematic in that the old-fashioned flat top bifocal is at the bottom of the lens.  If you try to look at the sights through the bifocal, not only is it awkward but it makes the distant target almost impossible to see.  A better option for glasses is a progressive addition lens or “no-line” bifocal.  Since the power is progressively stronger toward the bottom, a smaller head tilt is required and often there is a “sweet spot” that can help focus the front sight without excessive blur on the rear sight and distant target.  Of course this is really only helpful if you are target shooting and standing fairly still.  In a real self defense scenario, you are going to be looking through the top distance portion of your glasses and basically point shooting.  Hopefully, if you regularly practice, even dry firing, your muscle memory will kick in and focus on that front sight.

I personally have had good luck with a multifocal soft contact lens, the Air Optix Multifocal.   It is like a “no-line” bifocal but the bifocal is circumferential, just like a bulls-eye.  It helps to see at all the distances needed at the same time, sort of like a “peep hole’ sight works on certain target rifles.  There are some other brands as well.

Rifles and shotguns are tougher to use at bifocal age but since the front sight is significantly further away from the eye, it is easier to focus on with the top part of the glasses prescription. Of course a red dot scope and ideally, a laser is ideal for sighting at shorter ranges, especially in a home defense scenario.  You know exactly where that bullet is going to with a laser.  red or green (green is better) laser pointing at a bad guy’s chest is very intimidating and can diffuse a dangerous situation often without firing a shot.

Focus on the front sight as you get your sight picture and you will typically hit what you are aiming at.

If you are lamenting the worsening of your vision and how it’s harder to shoot, don’t feel too bad.  If it makes you feel better, even John Wayne in the movie, Big Jake, had to start using a sawed off shotgun due to “short sighted eyes!”

Courtesy of Dumas Vision Source, PLLC and Dr Tory W. Moore, Optometric Glaucoma Specialist.    Serving the Dumas, Texas,  Moore County and upper Texas Panhandle area for 21 years.   Call (806) 935-2020 for appointment or visit our optical gallery without an appointment.  Connect on Twitter @eyedocdumas  and like our Facebook business page:  Dumas Vision Source You also can visit our website www.visionsource-dumas.com for more information.   Tory Moore, OD  – “A Hometown Eye Doctor You Know and Can Trust!”

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Eye Myth Busters #2 – Pinhole Glasses to Train Your Eyes to Not Need Glasses

15 11 2013

You remember.  1973.  You see the ad in the back of a comic book.  X-ray glasses!  Every young man’s fantasy.  As an adult, you think, “Ugh, some things are better left unseen.”

Some things just seem to be too good to be true, until you waste your money and find out the product doesn’t end up to do what was advertised.  Remember Blue Blocker Sunglasses?  “As Seen on TV!”  They did actually help the contrast by blocking the blue end of the light spectrum but were so cheaply made and the reddish-orange color was not very cosmetically appealing.  They also skew the way colors look.  It made your grass look really green though!

Pinhole glasses.  That one has been around for quite some time too but they have made a resurgence in the last decade.  Lenses that have multiple holes in them that help train your eyes so you don’t need glasses.   Sure….  And I’ve got some swampland I will be willing to sell you…for a bargain price!

Looking through a pinhole will help you see better if you need vision correction, not a medical eye problem.  It works by eliminating all the light rays that are coming into your eye at an angle.  The only light that can enter through the small aperture is coming in perpendicular to your pupil and will land on your retina to see without needing to be bent.  The only problem is….YOU HAVE TO LOOK THROUGH A SMALL HOLE FOR IT TO WORK!

You cannot “train” your eyes or brain to get better vision.  It’s simple physics and anatomy.  Blurry vision either comes from refractive error or a medical problem.  If it’s refractive error, that comes from the shape of one or more parts of the eye not being optimal (nearsightedness, farsightedness, astigmatism) or by the lens of the eye not being able to accommodate or flex any longer (presbyopia).  You cannot affect the shape of eye parts to see better by wearing glasses.  Period.   Technically, you CAN temporarily improve your vision by wearing certain hard contacts (orthokeratology) at night to mold the eye to a certain shape for during the day but I don’t recommend that.

In the end, there is no way to get better vision except to put a lens in front of the eye to help bend light to a sharp focus in your eye or do some kind of surgery (Lasik, cataract, etc.) to change the shape or refractive power.

So the next time you see some kind of ad with some salesman with an Australian accent for Super Specs from Ronco promising to get rid of glasses, just laugh and switch on by.    Maybe save your money for those new fat burner pills that make your lose weight without eating less and exercising!

Courtesy of Dumas Vision Source, PLLC and Dr Tory W. Moore, Optometric Glaucoma Specialist and Diplomate of the American Board of Optometry.    Serving the Dumas, Texas,  Moore County and upper Texas Panhandle area for 23 years.   Call (806) 935-2020 for appointment or visit our optical gallery without an appointment.  Visit our website www.visionsource-dumas.com for more information.  Like our Facebook business page:  Dumas Vision Source  and you can also connect on Twitter @eyedocdumas

Tory Moore, OD  – “A Hometown Eye Doctor You Know and Can Trust!”





For Your Eyes Only

8 11 2013

Ever seen the spy type movies where the government agent puts his eye up against a camera and a laser seems to scan across his eye like a grocery store bar code scanner?  It is for real.  They scan the retina to identify people since the retina in everyone’s eyes is unique, like a fingerprint.  No one looks just the same.  Well, we can do the same thing in our office!  Yes, we can identify you if you are a secret agent!   Just kidding.

However, we can identify various eye diseases and tumors or signs of underlying medical disease such as diabetes, high blood pressure, high cholesterol, or blood disorders when they affect the blood vessels in the eye and leak.

When you look into the Optomap instrument, a digital camera system captures an image of the back of your eye with the help of a mirror and two different colored laser lights.  It is painless and is quicker than you can blink your eye.

An Optomap retinal exam provides:
• A scan to confirm a healthy eye or, to detect the  presence of disease.

• An overview or map of the retina, giving your doctor a more detailed view than can be achieved by other means.

• The opportunity for you to view and discuss the optomap images of your eye with your doctor at the time of your exam.

• A permanent record for your medical file, enabling your doctor to make important comparisons if  potential  problems show themselves at a future examination.

This is an example of the difference between looking inside with just a small pupil versus looking at the retina with an Optomap image.  As you can see, it provides a much better overall picture at one time of the state of the retina.  Much like a satelite picture is good for a broad perspective.  Then if something is noted, we can isolate in on a specific area with higher magnification at the microscope.

It does not replace the need for dilation, it only assists in the total examination of the eye to ensure everything is healthy.

optomap-scan
The Optomap Retinal Exam is fast, easy, and comfortable.  It does not cost very much and I recommend it highly at every visit for everyone, especially young kids.

Come in for a comprehensive eye exam and have your retina mapped.  It’s our mission, not impossible,  to save your vision!

Courtesy of Dumas Vision Source, PLLC and Dr Tory W. Moore, Optometric Glaucoma Specialist and Diplomate of the American Board of Optometry.    Serving the Dumas, Texas,  Moore County and upper Texas Panhandle area for 23 years.   Call (806) 935-2020 for appointment or visit our optical gallery without an appointment.  Visit our website www.visionsource-dumas.com for more information.  Like our Facebook business page:  Dumas Vision Source  and you can also connect on Twitter @eyedocdumas

Tory Moore, OD  – “A Hometown Eye Doctor You Know and Can Trust!”





The Devil is in the Details!

17 05 2012

Or in this case, in your cornea.

The cornea is the clear covering on the outside front of your eyes.  It has five layers of tissue, with the bottom most layer called the endothelium.  It is a barrier to keep the fluid inside your eye from leaking out and making the cornea swollen and cloudy.

The health of the endothelium is largely affected by the amount of oxygen it gets.  Trauma, inflammation, eye surgery and aging can also adversely affect the health of the cells in the endothelial layer.  If the cells in this layer become damaged, the cornea can swell and cloud up causing blurred vision and permanent blindess.  You are born with only a certain number of these endothelial cells that do not regrow.  You have to make them last as long as possible.

Contacts that do not allow the cornea to breathe enough,  wearing contacts overnight that are not highly permeable to oxygen and not discarding disposable contacts at the replacement times recommended can cause permanent damage to these endothelial cells.

Until recently, observing the endothelium of the cornea was tricky with a microscope and many times damage or disease was not easily observed until the later stages.   Now there is a new, powerful microscope commercially available that magnifies this layer 240X and allows eye doctors to see the individual cells of the endothelium.  Made by Konan Medical, the Cellchek specular microscope makes detailed viewing and analyzing the endothelial cell layer much easier.

This allows doctors to prevent future damage to the corneal endothelial cells by changing contact lens brands or schedules and using topical medications.   Patients needing cataract surgery can have extra precautions taken to help prevent further damage due to the surgery.

Now that we have this advanced technology in my practice, I will be able to more accurately assess all potential or current contact lens wearers for any damage to their corneal endothelium.  Also we will be able to better predict possible complications from cataract surgery or corneal refractive surgery.

Schedule an eye exam with us at 935-2020 and let us look at those hopefully not, devilish eyes!

Courtesy of Dumas Vision Source, PLLC and Dr Tory W. Moore, Optometric Glaucoma Specialist.    Serving the Dumas, Texas,  Moore County and upper Texas Panhandle area for 21 years.   Call (806) 935-2020 for appointment or visit our optical gallery without an appointment.  Connect on Twitter @eyedocdumas  and like our Facebook business page:  Dumas Vision Source You also can visit our website www.visionsource-dumas.com for more information.   Tory Moore, OD  – “A Hometown Eye Doctor You Know and Can Trust!”