Ophthalmic Education:

Principles and Guidelines of a Curriculum for Ophthalmic Education of Medical Students: Chapter III: Cornea and External Diseases

On this page:

• Educational Goal
  
  
• Refractive errors
  
  
• Types of surgical techniques to correct refractive errors
  
  
• Newer procedures – with excimer laser
  
  
• Effectiveness of refractive surgery
  
  
• Risks associated with refractive surgery
  
  
• Success in refractive surgery depends on:
  
  
• Clinical Competencies

Educational Goal: 

Students should understand the eye as an optical system and should know how refractive surgery corrects common refractive errors of emmetropia, myopia, hyperopia, and astigmatism.

A. Refractive errors.*  

1. Myopia – long eye, steep cornea, or both.*

2. Hyperopia – short eye, flat cornea, or both.*

3. Astigmatism – uneven curvature of cornea.*

4. Presbyopia – inability to focus at near due to aging.*

B. Types of surgical techniques to correct refractive errors.***

1. Incision – weaken cornea structurally to change curvature.*** (REF. 22 Fig. J01, J02, J16)

2. Lamellar – change cornea shape with addition or removal of tissue.***

3. Thermal – shrink corneal collagen to steepen or flatten the anterior corneal curvatures.***

4. Intraocular lens implantation with or without removal of crystalline lens.***

C. Newer procedures – with excimer laser.***

1. Photorefractive keratectomy (PRK).*** (REF. 22 Fig. J17, J18)

2. Laser in situ keratomileusis (LASIK).*** (REF. 22 Fig. J06, J07, J08, J09, J10, J11, J13, J14, J15)

D. Effectiveness of refractive surgery.***

1. Continual improvement.***

2. LASIK may be more predictable than radial keratotomy.***

3. Uncorrected visual acuity of 20/40 or better in most patients.***

4. Larger range of treatable refractive errors.***

E. Risks associated with refractive surgery.***

1. Infection.***

2. Loss of best-corrected visual acuity.***

3. Overcorrection, under correction, regression to baseline refractive status.***

4. Visual aberrations such as glare and halos.***

F. Success in refractive surgery depends on:

1. Careful preoperative evaluation.***

2. Exclusion of systemic diseases and eye disorders that may be contraindicated.***

3. Options, risks, and benefits of each procedure.***

Clinical Competencies

Students should:

• Understand refractive errors and their relations to eye length, corneal curvature, and lens status.*
• Describe refractive surgical theory and practice.***
• Understand risks and benefits of commonly discussed and performed refractive procedures.***

* Basic Level: Necessary in the education of medical students worldwide.

** Standard Level: A higher level of ophthalmic understanding than the basic curriculum of most international medical students.

*** Advanced Level: Advanced cognitive and clinical skills more appropriate for students who seek further training in ophthalmology, which may be covered in an ophthalmology elective in medical school.

(Also see: More on Educational Priorities)

Next: XIV. References

Also see:

• Table of Contents of the "Principles and Guidelines of a Curriculum for Ophthalmic Education of Medical Students"
  
  
• Education of Medical Students in Ophthalmology
  
  
• Resources for Ophthalmic Education of Medical Students