Pingelapese achromatopsia: correlation between paradoxical pupillary response and clinical features

Area of Science:

• Ophthalmology
• Genetics
• Visual Neuroscience

Background:

• Pingelapese achromatopsia (PA) is a rare genetic disorder characterized by complete color blindness.
• Clinical features typically include reduced visual acuity, nystagmus, and photophobia.

Purpose of the Study:

• To investigate the paradoxical pupillary constriction in darkness observed in PA patients.
• To determine the relationship between this pupillary response and other clinical manifestations of PA.

Main Methods:

• Ophthalmic examinations were conducted on 27 PA patients, including visual acuity and color vision tests.
• Pupillary responses to light and dark were recorded using an infrared video camera and analyzed.
• The ratio of pupil size in darkness to light was calculated to quantify the paradoxical response.

Main Results:

• 85% of PA patients displayed paradoxical pupillary constriction in darkness.
• A significant correlation was found between marked paradoxical pupillary constriction and lower visual acuity and Ishihara color vision scores.
• Mean visual acuity was 20/400, with significant color vision deficits.

Conclusions:

• Paradoxical pupillary constriction in darkness is a common feature in Pingelapese achromatopsia.
• The intensity of this pupillary response is linked to the severity of visual impairment and color vision deficiency.
• This finding aids in understanding the complex clinical presentation of achromatopsia.