🌟 Cues

• Structure and functions of cornea, iris, lens
• Phototransduction process
• Refractive media of the eye
• Photoreceptors: Rods vs Cones
• Visual pathway and lesions
• Corneal transparency and refraction disorders
• Glaucoma types and treatments

🗒️ Notes

• Cornea: Highly sensitive, transparent structure allowing light passage. Contains receptors for pain, touch, and temperature.
• Lens: Transparent, biconvex elastic structure providing 30% of the eye’s total diopteric power. Key role in accommodation for near vision.
• Phototransduction: The conversion of light into electrical signals by photoreceptors (rods and cones) in the retina.
• Retina: Photosensitive layer responsible for detecting light and converting it into neural signals. The center-surround organization enhances spatial pattern recognition.
• Refractive Media: Includes the cornea, aqueous humour, lens, and vitreous humour. These structures are key to light focusing and vision clarity.
• Visual Pathway: Light detected by the retina travels through the optic nerve to the brain for interpretation. Lesions in this pathway can result in visual deficits.
• Glaucoma: Increased intraocular pressure causing damage to the optic nerve. Treatment includes medications (e.g., carbonic anhydrase inhibitors) or surgery.

📝 Summary

Vision involves a complex process starting with light entering the eye through the cornea and lens, passing through the refractive media, and reaching the retina. The retina converts this light into electrical signals that are processed by the brain. Key structures such as the cornea, lens, and aqueous humour maintain clarity and focus. Disorders like astigmatism and glaucoma affect vision, requiring corrective lenses or medical treatment.