OCULAR MOTILITY LABORATORY (DD_OMLAB)
LOUIS STOKES CLEVELAND DEPARTMENT OF VETERANS AFFAIRS MEDICAL CENTER
School of Medicine
10701 East Boulevard
Mail Code #151W
OH 44106, USA
Fax: (216) 231-3461
from this page contains no medical advice.
You should always consult your doctor about INS treatments.
document was created by Z. I. Wang and edited by Dr. L.F. Dell’Osso.
Note: In this document, we have presented very complex
scientific information in laymen’s terms.
Patient Information Series:
3. THE TENOTOMY & REATTACHMENT PROCEDURE
Before the tenotomy & reattachment
(T&R) procedure, if you were the
person taking this photo, when you look at the group of people without turning
your head, this may be what you see.
farther away from your “null point”, the worse you see. You may have to turn your head to see each person clearly and
identify his/her face. It will take you a while
to identify all of them.
same thing happens in your life too: when you are trying to find your friend
who is standing in a room full of people, when you are looking for a road sign
while driving, and so on.
After the T&R procedure, when you look at the same group, your view will be clearer and
broader. You may be able to identify everybody in the picture much faster.
What is the tenotomy
and reattachment (T&R) procedure?
T&R procedure (or the Dell’Osso procedure) is
different from the Anderson-Kestenbaum (AK) or BiMedial Recession (BMR) surgeries, in that it does not move the location of the eye muscles. The T&R procedure is part of AK and BMR. In AK and BMR, the doctors
cut the muscles, move them to a different location in order to change the
position of the eye, and sew them back on. In the T&R procedure, the doctors cut the muscles and sew them back on
at the same location. The T&R procedure is
a simple, outpatient surgery. After the T&R procedure
you may see better, broader and faster.
The two photos in the previous page illustrate some of the T&R procedure’s effects.
Whom can the T&R procedure
T&R procedure is recommended for Infantile
Nystagmus [nĭ-STAG-muss] Syndrome (INS)
patients who do not have a “null point” or “convergence null” or whose a null
point changes with time.
Why does the T&R procedure
a pair of very tight rubber bands fixed to a ball. The rubber bands are like
the eye muscles and the ball is like the eyeball. When you shake the rubber
bands constantly, the ball will have a constant movement, just like nystagmus.
Now imagine loosening the rubber bands a little bit and shake the rubber bands
with the same amount of force. The eyeball will wiggle less now. The T&R procedure reduces the tension in the eye
muscles, and decreased the nystagmus in the same way.
How did the idea of
the T&R procedure
come about? How long has it been performed?
The T&R procedure was
first conceived in 1979 when Dr. Dell’Osso analyzed the eye movement recordings
from INS patients who had AK surgery. He found that the null point of those
patients was not only moved and but broadened also. Moving the eye muscles
shifted the null point, but did not explain the broadening effect. He then
hypothesized that cutting and sewing back the muscles without moving them would
achieve the broadening effect. This hypothesis was tested 20 years later, in
1998, on a dog with INS. The T&R procedure greatly reduced the dog’s
nystagmus. In 2001 and 2002, two National Eye Institute clinical trials were
performed on 10 adults and children, and the T&R procedure had positive
effects on most of the patients. Several hundred patients have had the T&R procedure since then. AK and BMR, which have the T&R procedure as part of them, have been performed for more
than 50 years.
Does the T&R procedure have any negative effects? Will the positive
had no known negative effects so far. The worst thing that can happen is no
improvement (your nystagmus stays the same). Research has shown that the worse
nystagmus you have, the better your chance for a higher percentage improvement.
Like AK and BMR, the T&R effects
last for years.