Spectral domain optical coherence tomography imaging of spectacular ecdysis in the royal python (Python regius)

Area of Science:

• Ophthalmology
• Herpetology
• Veterinary Medicine

Background:

• The ophidian spectacle, a transparent structure covering the eye, undergoes significant changes during ecdysis (shedding).
• Understanding these changes is crucial for diagnosing and treating anterior segment diseases in snakes.

Purpose of the Study:

• To document the dynamic changes in the snake spectacle, cuticle, and cornea during the ecdysis cycle.
• To evaluate the utility of spectral domain optical coherence tomography (SD-OCT) in visualizing these ocular structures in snakes.

Main Methods:

• Four royal pythons (Python regius) were monitored daily throughout a complete shed cycle.
• Ocular imaging was performed using SD-OCT, digital slit-lamp biomicroscopy, and external photography.
• SD-OCT captured nasal, axial, and temporal views of the anterior segment.

Main Results:

• SD-OCT provided high-resolution images of the spectacle, cuticle, subcuticular space (SCS), and cornea.
• The spectacle thickened and separated into cuticular and stromal layers, forming the SCS during ecdysis.
• The cornea remained unchanged, while the subspectacular space (SSS) was more distended peripherally.

Conclusions:

• SD-OCT is a valuable tool for imaging the snake anterior segment, particularly the spectacle and cornea, during all stages of ecdysis.
• The peripheral spectacle may be an ideal site for diagnostic or therapeutic interventions within the SSS.