Preliminary Clinical Observation Of The Surgery Outcome Of Infantile Nystagmus Sydrome

BACKGROUND AND OBJECTIVE:Infantile nystagmus syndrome (INS),that used to be called Congenital nystagmus (CN),is an ocular motor disorder that presents at birth or early infancy and is clinically characterized by involuntary and conjugate oscillation of the eyes, which often causes several complications such as amblyopia, lateral view, strabismus and torticollis. The etiology of INS is not fully understood, and this disease can’t be cured completely. Treatment in Infantile nystagmus syndrome is used to decrease the frequency and amplitude of nystagmus, improve the visual acuity, correct the anomalous head posture (AHP), and correct the strabismus. Current treatments are depending on the optical, medicine, biological feedback and surgical treatment, in which surgical treatment is given priority to. Various surgical procedures are used to treat both the AHP and strabismus seen in patients with INS, according to the compensatory mechanisms existing in the patients are different, surgical treatments are also different. For Dampening by Versions compensatory mechanism of the patients, the main treatment method is correcting the AHP, as for Anderson-Kestenbaum like procedures; if there is dampening by Vergence compensatory mechanism, artificial divergence surgery can be performed; if the patients has no compensation mechanism, the main treatment are Extended retroequatorial recession of rectus muscle, and four rectus muscle tenotomy and reattachment (T&R). This study aims to investigate the effects of the surgical treatments of INSMETHODS:33patients with infantile nystagmus syndrome aged from3to24, who underwent surgical treatments from June2011to April2012were retrospectively reviewed. Each patient underwent detailed enquiry with regard to the disease history. Of them23cases are male,10are female. The average age is8.28years. Horizontal nystagmus30example, vertical nystagmus1cases, the mixed nystagmus2cases.19example with horizontal AHP, The head tilt angles vary from15°to45°;1example with vertical AHP, the head tilt angles vary from10°to15°.14cases combine with strabismus. Pre-and postoperative examinations:both monocular and binocular visual acuity in primary and compensation head position, cycloplegic refraction, head tilt angle measured by Orthropedic goniometer, motility evaluation, anterior segment assessment, and fundus examination. The surgical plan depends on which dampening mechanisms the patient. Surgical consists mostly of recessions alone or the combination of recessions and resections depending on the amount of head turn and strabismus. If the patient has a strabismus, Anderson-Kestenbaum like procedures need to be performed on the fixing eye to correct the AHP, and strabismus correction is best planned on the non-fixing eye during the same surgical session. Follow-up time is during3.7weeks. A successful alignment was defined as-8～+8PD and AHP was-10～+10°in primary gaze while viewing distant.RESULTS:(1) Binocular visual acuity in primary head position of24patients increased from1line to5lines after operation;(2) AHP nearly disappeared in20cases, while the rest3declined obviously;(3) strabismus in8cases disappeared after operations, while the rest6declined obviously.CONCLUSIONS:Infantile nystagmus syndrome (INS) is an ocular motor disorder that presents at birth or early infancy and is clinically characterized by involuntary and conjugate oscillation of the eyes. Surgical treatment is still the most effectually way to dampen nystagmus, improve the visual acuity, correct AHP, and correct the strabismus simultaneously.