Doctor insights on:
Snelling Eye Chart
No: There are no known "excercises" that have been shown in good medical studies to permanently improve your best corrected vision. The visual system is not the same as your muscular system so more repetition does not improve your vision. Looking at an eye chart every day will allow you to test your vision and alert you to any changes or weakening of your vision. ...Read moreSee 1 more doctor answer
What are the differences between an eye chart that starts with 20/200 and another that starts with 70ft-21?
If you can read an eye chart at 20ft as well as a person with normal vision at 30ft is vision 20/30?
Visual acuity: Now a person with "normal" eye sight should be able to read the row of letters of a certain size ( the 20/20 line) standing or seated 20 feet from the eye chart as any person with normal vision should be able to do. Yes, your vision would be 20/30 if you can only see the chart at 20'. But if you can also see it at 30', you would have 20/20 vision. ...Read more
Borderline to what?: Eye charts are printed in discrete steps and depending upon where your vision falls, you have reached one or another border. For instance 20/200 is a common border for legal blindness. 20/40 is a common border in most states for legal driving. 20/20 is the commonly defined average normal vision. It is the upper border of superior vision at 20/15 or better. ...Read more
No: It depends on the size of the print on "line 8" and the distance from the chart. It is common for people to read the 20/15 equivalent, and not unusual to read 20/12, but the limit is probably about 20/10. ...Read more
Lengthens light path: Most offices do not have a 20 foot lane. But standards and available charts are made to reflect a 20 foot lane. The way to handle this is to use mirror (s) to reflect the image the proper distance to approximate a 20 foot lane. The letter images can also be enlarged or diminished as needed but this will change the standardization. A 20 foot light path is the standard. ...Read moreSee 1 more doctor answer
Read smallest line: The snellen chart is a graded series of letters or numbers smaller as you go down. The uncorrected vision is the smallest line easily read with each eye. Your ophthalmologist will present you with lenses to improve the level of the smallest line to hopefully get you to 20/20 - the standard of normal. It is a subjective test requiring your active input. ...Read more
Macular pucker, lost 1 line on eye chart in 1 year to 20/30. Is it likely next year I'll lose a line to 20/40 and continue at that rate of progression?
Hard to predict: Macular pucker is a variable condition and follows no rules. Yours may have maxed out or it might progress further. I am guessing you have a home testing card termed an Amsler grid to monitor any changes. If not, ask for one from your retinal specialist at the next appointment. ...Read more