Transactions 29th European Strabismological Association Meeting – de Faber (ed) © 2005 European Strabismological Association, ISBN 04 1537 211 9

Excessive recession of horizontal rectus muscles in surgical treatment of congenital nystagmus

M. Dogan, S. Akar, B. Gökyig˘it & O.F. Y lmaz

Beyo˘glu Educational and Research Eye Hospital, Istanbul, Turkey

ABSTRACT: In this study 24 patients files, who underwent excessive recession of horizontal muscles operation between December 1992–March 2003 in Beyoglu Educational and Research Eye Hospital, were evaluated retrospectively. All patients were congenital motor nystagmus without blockage and nystagmus amplitude decrease at primary position and ages were between 2–28 years (mean 14,50 9,49 years). 5 of them have exotropia, 7 of them have esotropia, 2 of them were albinos. The preoperative and postoperative monocular and binocular mean visual acuity at near and distance and nystagmus amplitude biomicroscobically recorded. The differences were statistically significant. The excessive recession of horizontal muscles in surgical treatment of congenital nystagmus is effective for decreasing nystagmus amplitude and visual improvement.

1INTRODUCTION

Congenital nistagmus is a well known syndrome of rhytmic, involuntary eye movements, primarily in the horizontal plane. Generally, it begins during the first several weeks of life(Cogan 1956). According to structural abnormalities, congenital nystagmus has two froms. First one is congenital motor nystagmus if no abnormalities and the other if there is abnormalities which are reasons of central vision impairement and called congenital sensorial nystagmus (Wybar 1967).

Many surgical methods used for congenital nystagmus. In 1950’s the main goal is to correcting the secondary head psition. Later to improve visual acuity, to decrease oscillopsia, to gain cosmetic improvement; fixation if the extraocular muscles to the periosteum of the lateral orbital wall, transposition of the parts of the horizontal and vertical rectus muscles, or free tenotomy of opposing rectus muscles were performed (von Noorden 1991).

Many authors reported, excessive recession decreased nystagmus intensity and improvement in visual acuity can obtained (von Noorden 1991, Bietti 1960, Alio 2003, Limon 1986).

2MATERIALS AND METHODS

All patients have congenital nystagmus. But no blockage and nystagmus amplitude decreases at primary position.

Retrospectively, all patient who underwent excessive recession of the all horizontal rectus muscles between 1992 December to 2003 March in amount of 10–13 mm were analysed. Preoperative and postoperative full ophthalmologic examination were noted. Preoperative and postoperative near and distance visual acuity monocular and binocular were recorded. The recession amount had calculated according to deviation in patients who have esotropia or exotropia. The same surgeon performed all operations. Nystagmus amplitude determined biomicroscopically.

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Table 1. Mean visual acuity results and p values.

3RESULTS

24 patients underwent excessive recession operation. 13 female (54.17%) 11 male (46.83%). The mean age was 14,50 9,49 (2–28) years. All have congenital nystagmus without blockage and their nystagmus amplitude decrease at primary position. 5 of them were Exotropia (20.83%) and 7 Esotropia (29,16%). Only 2 of them were Albinos (8,33%).

The mean follow up time was 14,90 (2–72) months.

The nystagmus amplitude in all patients was decreased biomicroscopically.

Binocular mean visual acuity at near and distance improved. Statistically significant (p 0,05). In 13 eye’s visual acuity of right eye at near increased (54.13%), in 10 eye’s visual acuity were the same (41.60%) and 1 eye’s visual acuity decreased (4.17%). Visual acuity of right eye at distance; 11 eye’svisual acuity increased (45.83%), 12 eye’s visual acuity were the same (50.00%) and 1 eye’s visual acuity decreased (4.17%). Visual acuity of left eye at near;15 eyes’visual acuity increased (62.50%), 9 eyes’s visual acuity were the same (37.50%), Visual acuity of left eye at distance; 13 eye’s visual acuity increased (54.16%), eye’s visual acuity were the same (29.16%), 4 eye’s visual acuity decreased (16.66 % ). Binocular visual acuity at near;16 eye’s visual acuity increased (66.66%), 7 eye’s visual acuity were the same (29.16%), 1 eye’s visual acuity decreased (4.16%). Binocular visual acuity at distance; 14 eye’s visual acuity increased (58.33%), 8 eye’s visual acu-

ity were the same (33.33%), 2 eye’s visual acuity decreased (8.33%).

The mean visual acuity results of preoperative and postoperative and p value of difference shown at table 1.

4DISCUSSION

Helveston et al. reported in 10 eyes visual improvement, 6 no change an 4 eye’s visual decreasing in 10 patients. Also they determined nystagmus amplitude biomicroscopically pre and postoperative and found decrease in 8 patients (Helvestone 1991).

Von Noorden performed this surgery in 3 patients and found succesfull (von Noorden 1991). They noted in 2 of 3 visual improvement.

Davis reported 7 of 12 albino patients, had 2 or more Snellen chart lines (58%) improvement after surgery.

According to our exprience excessive recession of horizontal muscles in congenital nystagmus is effective for decreasing nystagmus amplitude and increasing visaual acuity at near and distance.

REFERENCES

Alió JL. 2003. Visual performance after congenital nystagmus surgery using extended hang back recession of the four horizontal rectus muscles. Eur J Ophthalmol; 13: 415–42

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Bietti GB. 1960. Bagolini B. Traitement medicochirurgical du nystagmus. L’Annee Ther Clin Opththalmol.; 11: 268–293

Cogan DG. 1956. Neurology of the Ocular Muscles. Ed 2. Springfield, IL, Charles C Thomas

Helvestone EM. 1991. Large recession of horizontal recti for treatment of nystagmus. Ophthalmology, 98; 1302–5

Limon E. 1986. Surgical treatment of nystagmus, presented at first congress on practical management of nystagmus and strabismus, General hospital, Dr. Manuel Gea Gonzalez Mexico City, 5–7

Von Noorden GK. 1991. Large rectus muscle recessions for the treatment of congenital nystagmus Arch Ophthalmol 109; 2: 221–224

Wybar K. 1967. Significance of nystagmus in suspected. Can J Ophthalmol 2; 4

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