Neutralizing Peripheral Refraction Eliminates Refractive Scotomata in Tilted Disc Syndrome

Area of Science:

• Ophthalmology
• Neuro-ophthalmology
• Optometry

Background:

• Tilted disc syndrome is a congenital condition causing visual field defects that can mimic neurological diseases.
• These defects may result from transsynaptic retrograde degeneration.
• Differentiating tilted disc syndrome from acquired pathologies is clinically significant.

Purpose of the Study:

• To investigate if neutralizing peripheral refraction can eliminate visual field defects in tilted disc syndrome.
• To compare this technique's efficacy in tilted disc syndrome versus neurological deficits.
• To assess the potential of this method for differential diagnosis.

Main Methods:

• Used Humphrey Field Analyzer (30-2 grid) on 14 patients with tilted disc syndrome.
• Applied four refractive corrections: habitual near correction plus -1.00, -2.00, and -3.00 D negative lenses.
• Determined peripheral refractive errors using retinoscopy to calculate residual refraction.
• Assessed visual field defects quantitatively and qualitatively using sensitivities and probability scores.

Main Results:

• Reduced residual refractive error correlated with improved visual field defects (sensitivity and probability scores) in tilted disc syndrome.
• Patients with neurological deficits showed improved sensitivities but not probability scores.
• Negative addition lenses effectively reduced refractive error in the tilted disc syndrome group.

Conclusions:

• Neutralizing refractive error in posterior retinal bowing reduces apparent visual field defects in tilted disc syndrome.
• This technique may serve as a rapid diagnostic test to differentiate tilted disc syndrome from neurological deficits.
• The findings highlight the refractive component of visual field defects in tilted disc syndrome.