Are dark spots when blinking a common symptom of Acquired Idiopathic Blind Spot Enlargement Syndrome (AIBSES)?

Dark Spots When Blinking in Acquired Idiopathic Blind Spot Enlargement Syndrome (AIBSES)

Dark spots when blinking are not a characteristic symptom of Acquired Idiopathic Blind Spot Enlargement Syndrome (AIBSES), but photopsia (flashing lights) is a common presenting symptom of this condition. 1

Clinical Features of AIBSES

AIBSES is characterized by:

• Unilateral visual field loss in the blind spot area
• Acute onset photopsia (flashing lights)
• Minimal or no optic disc changes on fundoscopic examination
• Predominantly affects young adults (typically in their 20s and 30s)
• Strong female predominance 2

Key Symptoms

• Enlarged blind spot (primary diagnostic feature)
• Photopsia (flashing lights) - reported in 85% of patients 2
• Normal visual acuity in approximately 60% of cases
• Dyschromatopsia (color vision abnormalities)
• Afferent pupillary defects may be present

Diagnostic Findings

Imaging and Testing

• Optical Coherence Tomography (OCT): Gold standard for diagnosis, showing:
  • Marked peripapillary changes in the ellipsoid zone
  • Absence of inner/outer segment (IS/OS) line 1, 3
• Visual Field Testing: Shows characteristic blind spot enlargement
• Visual Evoked Potential (VEP): Typically no P100 latency delay 1
• Fundus Autofluorescence: Shows peripapillary changes
• Fluorescein Angiography: May show optic disc staining and retinal pigment epithelial lesions 2

Ophthalmoscopic Features

• Mild optic nerve swelling (in some cases)
• Granularity of macular pigment
• Subretinal white dots
• Peripapillary pigment disturbances 2

Differential Diagnosis

AIBSES is often misdiagnosed as optic neuritis due to low awareness 1. It should be differentiated from:

1. Multiple Evanescent White Dot Syndrome (MEWDS)

   • Similar clinical presentation but different ophthalmoscopic findings
   • Common indocyanine green imagery findings 4

2. Posterior Vitreous Detachment (PVD)

   • Also presents with photopsia but has different pathophysiology
   • Floaters are more common than blind spot enlargement 5

3. Acute Angle-Closure Glaucoma

   • Can cause visual disturbances but with different pattern and associated symptoms 5

Disease Course and Management

• Natural history: Photopsia typically decreases over time
• Visual field defects often persist despite treatment 2
• Some patients may experience full recovery within 6-12 months 1
• Recurrence reported in approximately 22% of cases 2

Treatment Options

• No well-established treatment protocol exists
• Some evidence suggests early corticosteroid treatment may support outer retinal reorganization 1
• Weight-adapted oral prednisolone tapered over 6-8 weeks has been used in some cases 1
• Regular monitoring is essential, especially given potential for recurrence 6

Clinical Pearls and Pitfalls

• AIBSES is often misdiagnosed due to low awareness
• Careful history taking with attention to photopsia and visual field symptoms is crucial
• OCT is the most valuable diagnostic tool for confirming AIBSES
• The condition predominantly affects young women
• Unlike PVD, which typically occurs between ages 45-65, AIBSES affects younger individuals 5, 1
• Patients should be monitored for potential recurrence or bilateral involvement

Remember that while dark spots when blinking are not characteristic of AIBSES, patients with this condition commonly report photopsia (flashing lights), which may be misinterpreted as dark spots by some patients.