Bilateral microphthalmos with cyst in a neonatal foal

Area of Science:

• Veterinary Ophthalmology
• Comparative Pathology

Background:

• Congenital ocular anomalies can significantly impact animal health and welfare.
• Early diagnosis and characterization are crucial for managing ocular conditions in foals.

Observation:

• A 1-day-old miniature horse filly presented with severe, congenital ocular abnormalities in both orbits.
• The right orbit contained a large, ulcerated orbital mass, while the left orbit showed signs of a non-visual eye.

Findings:

• Ocular ultrasound revealed a complex orbital mass in the right eye and a microphthalmic globe with a suspected lens in the left eye.
• Histopathology confirmed bilateral microphthalmos with cyst, a rare congenital defect, and indicated irreversible blindness.

Implications:

• This case highlights the importance of thorough ophthalmic examination in foals with suspected congenital defects.
• The findings contribute to the limited veterinary literature on microphthalmos with cyst, aiding future diagnosis and understanding of this rare condition.