An unusual association of acute acquired comitant esotropia and bilateral idiopathic optic neuritis in two boys: a case series

INTRODUCTION: Acute acquired comitant esotropia is characterized by sudden-onset, large-angle comitant esotropia occurring in adults and older children. The condition differs from infantile esotropia in its acute presentation, typically occurring after the age of 6 months, when binocular vision has developed. While many cases of AACE are idiopathic or attributed to functional factors such as excessive near work with digital devices, neurological etiologies can account for up to 10% of cases and must be investigated to rule them out. Here we are reporting an unusual association of acute acquired comitant esotropia and bilateral idiopathic optic neuritis in two boys. METHODS: Acute acquired comitant esotropia (AACE) is an uncommon form of esotropia that typically presents after early childhood and is characterized by the sudden onset of esodeviation without limitation of ocular motility. While most cases are idiopathic or associated with excessive near work, neurological causes must be systematically excluded. Here, we report two cases of AACE associated with bilateral idiopathic optic neuritis in the pediatric age group and emphasize the importance of comprehensive neuro-ophthalmic evaluation in these cases. RESULTS: Both patients presented with sudden-onset large-angle esotropia associated with diplopia and visual impairment. Visual evoked potential abnormalities and neuroimaging findings confirmed bilateral idiopathic optic neuritis. Treatment with systemic corticosteroids resulted in visual recovery, followed by successful strabismus surgery with excellent alignment and functional outcomes. CONCLUSIONS: AACE in pediatric patients should not be dismissed as benign without a comprehensive evaluation. This case series underscores the importance of neuro-ophthalmic assessment, including visual evoked potentials and magnetic resonance imaging, to identify rare but critical associations such as optic neuritis. Prompt recognition and appropriate treatment are essential for optimal visual and functional recovery.