Two-dimensional ultrasonography study of normal ocular structures in Turkmen horse.

Two-dimensional ultrasonography was used to study the normal eye structures of Turkmen horses, revealing significant differences in specific eye measurements related to age, but few differences related to sex.

Study Design and Subjects

• The study involved 30 clinically healthy Turkmen horses.
• Horses were divided into two age groups:
  • Group 1: Under 36 months old (3 males, 8 females)
  • Group 2: 36 months and older (8 males, 11 females)
• Both male and female horses were included to assess potential sex-related differences.

Ultrasonography as a Diagnostic Tool

• Ocular ultrasonography is a non-invasive, painless, and safe imaging technique.
• It provides clear images of the eye and adjacent structures useful in veterinary diagnosis.
• The application to Turkmen horses offers a way to obtain baseline anatomical measurements and helps detect abnormalities.

Key Ocular Parameters Evaluated

• Intercanthal distance (distance between the inner corners of the eyes)
• Globe diameter (size of the eyeball)
• Ciliary body volume and area (part of the eye involved in lens focusing)
• Iris thickness (colored part of the eye)
• Corpora nigra distance, volume, and area (structures on the iris unique to horses)
• Vitreous chamber size (space filled with gel behind the lens)
• Retinal/choroidal/scleral composite size (layers of the eye wall)
• Anterior chamber depth (space between the cornea and the iris)
• Central lens thickness (thickness of the lens responsible for focusing)
• Ciliary body thickness
• Corneal thickness measured in sagittal and dorsal planes

Findings Related to Age

• Statistically significant differences were found between the two age groups in many ocular parameters:
  • Intercanthal distance, globe diameter, and ciliary body measurements were larger or varied with age.
  • Iris thickness and corpora nigra measurements changed significantly, reflecting anatomical development.
  • Vitreous chamber size and retinal/choroidal/scleral composite sizes also differed between younger and older horses.
• Only anterior chamber depth, central lens thickness, and ciliary body thickness showed differences influenced by both age and sex.

Findings Related to Sex

• Overall, no significant differences in the measured ocular parameters were detected between males and females within each age group.
• Corneal thickness was similar between males and females in both age groups.
• No significant differences were noted between the left and right eyes of the horses examined.
• Measurements taken in sagittal versus dorsal planes showed no significant discrepancy, validating the consistency of views.

Implications of The Study

• The results establish a baseline for normal ocular anatomy and ultrasonographic measurements in Turkmen horses.
• Veterinarians can use these normative measurements to better identify deviations indicating ocular disease or abnormalities.
• This breed-specific data is critical because breed differences can influence eye anatomical parameters.
• Improved diagnostic accuracy can aid in the management and treatment of eye conditions in Turkmen horses.

Summary

• This study provides detailed ultrasonographic data on eye structures in Turkmen horses focusing on age and sex differences.
• Age significantly influences multiple eye measurements, reflecting development and maturation.
• Sex has a limited effect on ocular parameters, with only a few exceptions.
• The approach and findings enhance veterinary ophthalmology knowledge specific to this horse breed.