ANATOMY OF SCLERA

Posteriorly

The disorder is frequently associated with blue sclerae, dental abnormalities and progressive hearing loss.

Ans. Insertion of extraocular muscles

Ans. D: All of the above

Causes of blue Sclera:

• Pseudoxanthoma elasticum
• Osteogenesis imperfecta
• Ehlers-Danlos syndrome
• Marf an’s syndrome
• Alkaptonuria
• Hypophosphatasia
• Juvenile paget’s disease
• Normal in newborns
• Van der Hoeve’s syndrome

Ans. is ‘c’ i.e., Retinal detachment

Treatment of retinal detachment

• Retinal detachment surgery consists of three components : sealing retinal tears, reducing the vitreous traction on the retina and flattening of retina.
• It is important to find all retinal tears (holes) and seal them by laser photocoagulation, diathermy or cryoapplication.
• Scleral buckeling or external plombage or encirclage is a procedure to push the wall of sclera inwards to close the tear, reduce the traction and flatten the retina.
• Drainage of subretinal fluid helps to flatten the retina against the sclera.
• Intravitreal surgery (vitrectomy and gas injection) may also be employed.

o The thickness of the sclera varies according to location : ‑

• At the limbus, the sclera is 0^.8 mm thick.
• Anterior to the rectus muscle insertions, it is 0^.6 mm thick.
• Posterior to the rectus muscle insertions, it is 0^.3 mm thick (Thinnest portion).
• At the equator, it is 0^.5 to 0^.8 mm thick.
• At the posterior pole, it is greatest than 1 mm thick.

• Thinnest portion of sclera→ Posterior to insertions of rectus muscle.
• Thickest portion of sclera→ Posterior pole.