What causes sudden onset of esotropia (crossed eyes) in individuals of any age?

Sudden Esotropia: Causes and Clinical Approach

Sudden-onset esotropia requires prompt evaluation to distinguish benign accommodative causes from serious neurological pathology, with uncorrected hyperopia being the most common etiology but neuroimaging mandatory when neurological signs are present. 1

Primary Etiologies by Age Group

Children and Adolescents

Accommodative esotropia is the leading cause of sudden esotropia in children, typically presenting between ages 1-4 years but can occur later 1:

• Usually associated with uncorrected bilateral hyperopia 1
• May be precipitated by illness, fever, or minor trauma 1
• In 70% of cases, hyperopic correction partially or completely resolves the deviation 2

Nonaccommodative acquired esotropia presents with equal deviation at distance and near 1:

• No significant refractive error or no improvement with correction 1
• If acute onset with neurological signs/symptoms, neuroimaging is mandatory 1

Acute acquired comitant esotropia (AACE) is a distinct entity characterized by 3, 4:

• Sudden onset with equal angle in all gaze directions 3
• Often associated with myopia and excessive near work without glasses 4
• Mean deviation of 36 prism diopters at distance, 26 at near 4

Adults

Acute acquired comitant esotropia in myopic adults is particularly common 1:

• Typically occurs in young adults with uncorrected myopia 4
• Associated with prolonged near work and visual confusion 4
• Mean age 30 years in one series 4

Accommodative spasm can cause sudden esotropia with 5:

• Pupillary miosis and restricted ocular motility (spasm of near reflex) 5
• Blurred vision and binocular diplopia 5
• Responds to cycloplegic medications but may require prolonged treatment 5

Neurological Causes Requiring Urgent Evaluation

Cerebellar pathology can present initially as isolated esotropia 6:

• Greater esodeviation at distance than near suggests dorsal vermis lesion 6
• Smooth pursuit abnormalities (high latency of abducting eye) may be the only early sign 6
• Headache may develop months after esotropia onset 6

Indications for neuroimaging include 1:

• Acute onset with other neurological signs or symptoms 1
• Incomitant deviation suggesting restrictive or paretic etiology 3
• Failure to respond to hyperopic correction 1
• Associated smooth pursuit abnormalities 6

Sensory Causes

Sensory esotropia develops from unilateral vision loss 1:

• Structural ocular pathology (retinal disease, optic nerve disorders, dense cataract) 1
• Poor vision in one eye leads to inward deviation 1

Diagnostic Algorithm

Initial Assessment

1. Measure deviation at distance and near with prism and alternate cover test 1
2. Perform cycloplegic refraction to identify hyperopia 1
3. Assess ocular motility for restriction or paresis 1, 3
4. Evaluate smooth pursuit for latency abnormalities suggesting cerebellar involvement 6

Risk Stratification

• Low risk: Hyperopic child age 1-4 years, no neurological signs, deviation improves with correction 1, 2
• High risk: Acute onset with neurological symptoms, incomitant deviation, smooth pursuit abnormalities, or failure to respond to optical correction 1, 6

Repeat Evaluation

Repeat cycloplegic refraction is indicated when esotropia does not respond to initial hyperopic prescription or recurs after surgery 1

Management Approach

Optical Correction

• Prescribe full cycloplegic hyperopic correction first 1, 2
• 70% show partial or complete resolution with glasses alone 2

Prismatic Correction

For AACE with unstable angle 4:

• Prisms resolve diplopia in 90% of cases (27/30 patients) 4
• Offers good alternative when angle is unstable and surgery carries risk 4

Cycloplegic Treatment

For accommodative spasm 5:

• Cycloplegic medications are first-line 5
• May require prolonged course (up to 1 year) for complete resolution 5

Surgical Intervention

Reserved for 1:

• Persistent deviation after optical correction 1
• Partially accommodative esotropia 1
• Failed conservative management 4

Critical Pitfalls to Avoid

Dismissing isolated esotropia as benign when cerebellar tumors can present with esotropia as the sole initial symptom for months before other signs develop 6

Missing accommodative component by failing to perform adequate cycloplegic refraction, leading to unnecessary surgery 1, 2

Overlooking myopia in adults with AACE who perform excessive near work without correction 4

Delaying neuroimaging when smooth pursuit shows bilateral abduction latency, even without other obvious neurological signs 6