Surgery Options for Nystagmus

When considering surgery for nystagmus, most ophthalmologists would immediately think of the Kestenbaum or Kestenbaum- Anderson procedure. This procedure first described in the 50's in part by each of these ophthalmologists is designed to help realign the head or eliminate face turn in nystagmus with null point.

nystyg 1a
Nystagmus and decreased vision with head (face) straight
nystyg 1b
Nystagmus damped, vision improved with face left, eyes right

Clinical picture with null point nystagmus

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The principle of surgery for nystagmus with null point is to move muscles in order to mimic muscle tension (dextroversion as shown above) while eyes and face straight.

Some cases have periodic alternating nystagmus

nystyg 1c

nystyg 1d

Anderson � recess yoked rectus muscles

nystyg 1e

Kestenbaum � resect yoked muscles

Kestenbaum/Anderson - combines the two techniques

For example: in the cases shown here the aim is to duplicate the muscle tension in right gaze - left face turn while looking straight ahead.

nystyg 2a

Null achieved with face left

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Several authors have increased surgical numbers proportionally

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To achieve null with face straight

The numbers shown here have been called "straight flush".

But!! In many cases after Kestenbaum/Anderson surgery for null point nystagmus:

Pre Op This

Becomes

Post Op This

After surgery, the patient's face may be straight at the time of examination, but the opposite head turn is assumed to achieve comfortable vision.

This post op visual posture in opposite gaze is more comfortable in casual seeing. Why does this occur?

It is uncomfortable to maintain gaze in the extreme - try looking far left or right with your face straight - it hurts! Although the Kestenbaum/Anderson continues to be the "standard" answer to the question, "How do you treat null point nystagmus?", it may be more talked about than performed.

A potentially more effective procedure for null point nystagmus is the"Large Anderson" - for example:

Null

Surgery

Recess M.R. 7.0mm or 12.5mm from Limbus

Recess L.R. 10.0mm or to anterior insertion of the I.O.

For treatment of congenital motor nystagmus and sensory nystagmus, large recession of the four horizontal rectus muscles has been effective.

nystyg 3a Or

Idiopathic congenital motor

nystagmus without a null point

nystyg 3b

Sensory nystagmus

From {

Albinism

Retinal Dystrophy

Congenital Optic Atrophy, etc.

nystyg 3c

Result of large 4 muscle recession

Visual acuity same or +/- 1 line better - For example:

Pre Op {

20/200

20/100

20/70

Post Op{

20/100 (or 20/200)

20/80 (or 20/100)

20/60 (or 20/70)

Vision has never been worse

in our experience after 4 muscle recession

2) Post op XT in < 10% (earlier this was 40% when M.R. recessed same distance as L.R.) We now recess M.R. less - do not do equal recession of medial and lateral recti.

3) Patients have approximately 50% reduction in amplitude of nystagmus - but no change in frequency

4) Resulting in approximately 50% improvement in recognition time:

Recognition time is the minimum time of exposure required for a patient to see an optotype at his/her visual threshold. Recognition time was measured by projecting optotypes at threshold while employing increasing shutter speeds or shorter exposure time.

A shorter recognition time allows a person to assess the environment more accurately in a shorter time thereby enabling greater visual efficiency. (Sprunger)

In the past 10 years more than 100 patients have obtained good to excellent results from this procedure. However, the results are difficult to quantify in the usual clinical setting. Eye movement recording by electronystagmography is the only way to show convincingly and objectively the results of surgery. However, the fact that several family members have undergone the procedure after observing results at home is a very positive sign that the procedure is effective.

Note!! A patient's nystagmus is probably at its worst when observed by the ophthalmologist in the usual examination setting. This makes assessment of results difficult in the office. The only accurate assessment of the effect of surgery remains the comparing of pre and post operative nystagmus (EMG or EOG), but this too is subject to examination anxiety.

The 4 muscle recession is not useful for acquired nystagmus with oscillopsia, such as occurs with multiple sclerosis, etc. More about this subject and about vertical nystagmus in another Minute.

Editor-in-Chief: Eugene M. Helveston, M.D.

Associate Editor: Faruk H. Orge, M.D.

Editorial Board: Bradley C. Black, M.D.

   Edward O'Malley, M.D.

   David A. Plager, M.D.

   Derek T. Sprunger, M.D.

   Daniel E. Neely, M.D.

   Naval Sondhi, M.D.

Senior Editorial Consultant: Gunter K. von Noorden, M.D.

Graphics: Michelle L. Harmon

Technical Support: George J. Sheplock, M.D.