Ocular findings and strabismus surgery outcomes in Chinese children with Angelman syndrome: Three case reports.

Rationale: Angelman syndrome (AS) is an uncommon genetic disease characterized as serious retarded mental development and ocular abnormality.
Patient Concerns: This report aims to present the ophthalmological features, and identify the diagnosis and outcomes of strabismus surgery in AS patients.
Diagnosis: Three children with exotropia were diagnosed with AS based on their typical clinical features.
Interventions: All patients underwent multiplex ligation-dependent probe amplification (MLPA) analysis and accepted lateral rectus recession surgery with the assistance of intravenous combined inhalation anesthesia.
Outcomes: The maternal heritage deletion of chromosome 15q11.2-q13 was verified in all patients by MLPA. All patients with strabismus could not cooperate during the vision test, and had astigmatism. The strabismus type of AS patients was horizontal exotropia, and no vertical strabismus was found. One of these patients was combined with high myopia. The hypopigmentation on the hair and iris was ubiquitous. However, retina pigmentation was normal. After different degrees of lateral rectus recession, the exotropia was significantly relieved, and the surgical effects were stable postoperatively.
Lessons: Horizontal exotropia is the major strabismus type. Severe intellectual disability, hyperactivity, and speech impairment are the common characteristics of AS children. Its examination and operation design remains challenging. Thus, repeated examinations and intelligence rehabilitation are essential.