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Astigmatism . Dr.Nita Shanbhag Dr.Swapnesh Sawant. Long questions (any 1). Describe astigmatism under following headings with ray diagrams Etiological classification Refractive types with help of sturm’s conoid Signs & symptoms Treatment . Short answer questions (any 3).
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Astigmatism Dr.Nita Shanbhag Dr.Swapnesh Sawant
Long questions (any 1) • Describe astigmatism under following headings with ray diagrams • Etiological classification • Refractive types with help of sturm’s conoid • Signs & symptoms • Treatment
Short answer questions (any 3) • Jacksons cross cylinder • Anisometropia • Aniseikonia • Refractive surgery for astigmatism
Multiple choice questions • Manifestation of presbyopia in hypermetropia occurs at : • A usual age of 40 years • An earlier age than usual • A later age than usual • Does not manifest at all
The chief factor responsible for hypermetropia is: • Curvature of the cornea and lens • Abnormal displacement of the lens backward • Axial length of the eye ball • Refractive index of the ocular media
Lens required for correction of aphakia in previous emmetrope: • + 10 D • - 10 D • + 5 D • + 15 D
In an aphakic eye the image magnification is about: • 15% • 10% • 30% • 20%
In an aphakic eye the posterior focal distance is: • 23 mm • 15 mm • 20 mm • 25 mm