*ATB - DISTANT VISUAL ACUITY TESTING
(DD Form 2808, Block 61. 'DISTANT VISION') [As of: 1 May 2002]*

- IMPORTANT NOTE ABOUT 20/20 DISTANT VISUAL ACUITY
STANDARD FOR FDMEs! Per AR 40-501, paragraph 4-12, a (1),
"...no more than 1 error per 5 presentations of 20/20 letters, in
any combination, on either the Armed Forces Vision Tester
(AFVT) or any projected Snellen chart set for 20 feet."
- Issue: AFVT line has 10 letters but is split into two sets of five letters
positioned next to each other on the same line. You may still test the
entire line, if desired, but the patient is still only required to get
*4 out
of 5* letters that are on a 20/20 line to be considered a 'pass' for an
FDME. Therefore, entries of 20/20 or 20/20-1 are both passing entries.
Most projected Snellen charts have 6 letters (some have 4, 5, 7, or 8
letters) per line. The regulation allows for presentation of 5 letters "in
any combination" so you may meet the requirement. If in que stion,
refer to the Eye Clinic for verification.

The standard they taught in physiological optics at UAB was "smallest line
with half or more right."  But in the clinic, or in a psychophysical
experiment, the difference between one line and another seldom alters
anybody's career.

The AF and the FAA etc spell out qualification standards as fairly as they
can, and it isn't always what a purist would use.

-MT

Mike, Can you help me find where I am standing according to Army regs?
Let me quote the standard procedures for the Army exam...

UPDATED ENTRY STANDARDS FOR CLASS 1/1A FLIGHT DUTY MEDICAL EXAMINATIONS.
(as of 28 March 2002):

Hyperopia greater than +3.00 diopters of sphere (in any meridian by
transposition in either eye)
Myopia greater than -1.50 diopters of sphere (in any meridian by
transposition in either eye)
Astigmatism greater than +/- 1.00 diopter of cylinder in either eye
Must meet above standards in both plus-cylinder and minus-cylinder
formats, so transpose to ensure patient meets standards
(spherical equivalent method does not apply).

For example, the cycloplegic refraction of:
-1.00 - 0.75 x 180 (in minus-cylinder format)
might appear qualified at first glance. However, after transposition
into plus-cylinder format of:
-1.75 + 0.75 x 090 (in plus-cylinder format)
it is apparent that this refraction is disqualifying because the sphere
amount exceeds -1.50.

Transposition Review:
1. Algebraically sum the sphere and cylinder powers
2. Change the sign of the cylinder power
3. Change the axis by 90 degrees.

Important Note for Eye Care Providers
A cycloplegic refraction is NOT necessarily equal to the refraction you
would give for spectacle lenses. If a patient is "on the
border" of being qualified or disqualified, it is best for the Army and
for the patient to use the "least amount of prescription
needed to see within standards" approach.
For example, if a patient has a cycloplegic refraction that is +/- 0.25
diopters outside of standard but can still read to the
20/20-1 standard with the refraction amount that is WITHIN standards,
enter the lesser amount.
Do NOT, however, try to "push" the 20/20-1 on borderline cases. These
patients receive an entirely new cycloplegic exam
once they come to Fort Rucker to enter flight school. If they are
outside of the standard, they will be required to request an
exception-to-policy which will likely be disapproved. Use your
professional judgement but do not allow someone to come to
flight school knowing he/she has a good chance of failing their detailed
cycloplegic exam upon arrival.

So what is mine after this transposition? As far as I understood, they
are not doing the spherical eq. for flight duty exams.

Thanks...