A Case of Pediatric Idiopathic Intracranial Hypertension Presenting with Divergence Insufficiency

An 11-year-old female presenting diplopia only at distance was found to have comitant esotropia of 20 prism diopters (PD) at distance and normal alignment at nearer proximity. Other ocular movement, including abduction, was normal and a thorough neurologic examination was also normal. The deviation angle of esotropia was increased to 35 PD in 6 months, and a brain magnetic resonance imaging with venogram at that time demonstrated no intracranial lesion. A lumbar puncture showed increased opening pressure but the cerebrospinal fluid composition was normal. The patient was diagnosed as having idiopathic intracranial hypertension and treated with oral acetazolamide. Three months after treatment, the deviation angle decreased to 10 PD. This is a case report of divergence insufficiency in pediatric idiopathic intracranial hypertension, with an increasing deviation angle of esotropia. Although sixth cranial nerve palsy is a common neurologic manifestation in intracranial hypertension, clinicians should be aware of the possibility of divergence insufficiency. Also, ophthalmoparesis may not be apparent and typical at first presentation, as seen in this case, and therefore ophthalmologists should be aware of this fact, while conducting careful and proper evaluation, follow-up, and intervention.