ABSTRACT
PURPOSE: The aim of this study is to evaluate the incidence of consecutive strabismus after infantile nystagmus surgery and its potential risk factors. METHODS: A retrospective study including 89 patients was conducted. Patients presented infantile nystagmus (idiopathic or ocular disease-associated nystagmus) without previous or coincidental strabismus. Sex, age at surgery, amblyopia, botulinum toxin (BT) injection before surgery, spherical equivalent, anisometropia, surgery procedure (Anderson's or retroequatorial recessions of four horizontal recti), and follow-up were analyzed. Kaplan-Meier and univariate Cox regression were performed. RESULTS: The median age at surgery was 5 years. The median follow-up was 36 months. The incidence of consecutive strabismus was 11.2%. There were eight patients with exotropia and two patients with esotropia. Consecutive strabismus was associated with severe bilateral amblyopia (p = 0.036), previous treatment with BT injection (p = 0.025), and large recessions of the four horizontal muscles (p = 0.001). The hazard ratio for patients with severe bilateral amblyopia was 5.4 (95% CI 1.1-25.8), and for patients previously treated with BT was 6.1 (1.3-29.3). The survival rate was 95.4% at 6 months and 88.5% at 3 years. CONCLUSION: Severe bilateral amblyopia, previous BT treatment, and type of surgery seem to be associated with consecutive strabismus after infantile nystagmus surgery. Most cases appear within the first months after surgery.
Subject(s)
Nystagmus, Pathologic/surgery , Oculomotor Muscles/surgery , Ophthalmologic Surgical Procedures/adverse effects , Postoperative Complications/epidemiology , Risk Assessment/methods , Strabismus/etiology , Vision, Binocular/physiology , Child , Child, Preschool , China/epidemiology , Eye Movements , Female , Follow-Up Studies , Humans , Incidence , Male , Nystagmus, Pathologic/physiopathology , Oculomotor Muscles/physiopathology , Postoperative Complications/etiology , Retrospective Studies , Risk Factors , Strabismus/epidemiology , Strabismus/physiopathology , Strabismus/surgery , Syndrome , Visual AcuityABSTRACT
INTRODUCTION: The treatment of strabismus associated with myopia is often a therapeutic challenge for the ophthalmologist. The strabismus associated with myopia has certain peculiarities and there are even certain types of strabismus that occur exclusively in myopia, such as strabismus fixus, requiring treatments with specific surgical techniques. MATERIALS AND METHODS: It is important to make a correct differential diagnosis, because there are many conditions described with this association. A review is presented of strabismus associated with myopia, together with its treatment adjusted to refractive error. RESULTS: Measurements of strabismus may be altered by the prismatic effect of the spectacles. Surgical results may be unpredictable if myopia is not taken into account. Better results were obtained with the techniques of anatomical replacement described by Yokoyama than with traditional retro-insertion-resection. CONCLUSION: For the diagnosis and appropriate treatment of strabismus, it is important to make a correct measurement of the angle of deviation, and perform image tests prior to surgery in certain cases. The anatomical characteristics of the myopic eye should also be taken into account during surgery.
