Its a quick revision on Myopia for Exam point of view! The slides are made in such a way that you can answer questions in exams easily

1. MYOPIA
By Priyanka ( MBBS Student )

2. Myopia
• Is a type of refractive error, When a ray of light from
infinity are focused in front of retina when accommodation
is at rest!

4. Types
Congenital myopia
Simple myopia
Pathological myopia
Developmental myopia

5. Simple myopia
• Axial – longer axial length
• Curvature- more curved corneal surface
• Index- high refractive power of anterior segment
• No degenerative changes we see in fundus
• Its not progressive after adolescence when 5 or 6
diopters is attained

6. Pathological myopia
• Pathological axial myopia-
Progressive , finally amounting to 15 – 25D or more
Degenerative changes in fundus seen later
• Pathological curvature myopia-
 Keratoconus
• Pathological index myopia-
Immature cataract( increased RI of Nucleus of lens) and
diabetes

7. Developmental myopia
• Rare
• Born with long eyeball
• Fundus lack pigmentation
• Choroid vessels are prominent
• Myopic crescent may be seen
• Progression is rare

8. Problems one face
• Blurring of vision
• Headache
• Discomfort
• Apparent Convergent squint
• Increased Sensitivity to light

9. General signs
• Prominent longer eyes
• Large, curved cornea
• Thin sclera
• Large & sluggish pupil
• Apparent convergent squint
• Deep anterior chamber
• Ciliary atrophy
• Vitreous degeneration with opacities

10. Fundus changes
• Optic disc changes
Large & pale
Myopic crescent at temporal edge
Supra traction crescent
• Degenerative changes
Atrophic patches in macula + heaping up at margins
Foster fuschs’ spots in macula d/t sub retinal
neovascularization & choroidal hemorrhage
Cystoid degeneration at periphery of retina
Retinal atrophy

11. Posterior staphyloma
Tigroid Fundus
Accentuation of foveal reflex
Vitreous degeneration with opacities + PVD (Weiss
reflex)

12. A)Normal right eye B)Tigroid fundus

13. Fundus photographs of the both eyes. Both eyes show
myopic tigroid fundus and myopic tilted disc with peripapillary
atrophy.

14. Modalities of treatment

15. Spectacles
• Concave lens with appropriate powers
• Treatment of choice for low myopia

17. Contact lenses
• In cases of high myopia because they avoid
peripheral distortion & minification which is produced
by strong concave spectacle lens

18. Surgical treatment
• The purpose of refractive surgery is to reduce or
eliminate dependence on optical correction devices,
glasses or contact lenses.
• Surgical techniques that correct myopia are divided into
2 categories: corneal surgical techniques and
intraocular techniques.

19. • Refractive corneal surgery corrects myopia by
modifying the cornea’s curvature to reduce its power
and ensure the images form on the retina.
• Refractive intraocular surgery obtains the same result
by implanting corrective lenses inside the eye.
• There are currently three most frequently
used refractive corneal surgery techniques:
• PRK (Photorefractive Keratectomy),
• LASIK (Laser Assisted In-Situ Keratomileusis)
• SMILE (Small Incision Lenticule Extaction).

20. Photorefractive Keratectomy
• PRK is the most superficial technique of the three. After
removing the epithelium (the most superficial layer of the
cornea), an excimer laser is applied to sculpt the cornea
and correct the patient’s diopters.

21. Laser Assisted In-Situ Keratomileusis
• When it comes to the LASIK technique, first a
femtosecond laser makes a laminar cut (called a flap) in
the anterior cornea tissue leaving an upper hinge.
• Then the lamina, which has been previously cut, is lifted
and, in the same way as the PRK technique, the Excimer
laser is applied before repositioning the flap on the
treated cornea.

23. Small Incision Lenticule Extaction
• With the SMILE technique, a femtosecond laser dissects
a lenticule in the corneal thickness (designed based on
the diopters of each patient) which is then removed
using a small incision.

25. Refractive intraocular surgery
• Intraocular techniques include implantation of lenses
called phakic lenses in front of the crystalline lens
leaving the latter intact and the removal of the
crystalline lens with the intraocular lens implant in the
capsular bag.

26. Genetic counseling (prophylaxis)
• As pathological myopia has strong genetic
basis
• Hereditary transfer of disease can be
decreased
• By advising against marriage between 2
individuals with progressive myopia

27. Complications
• Retinal detachment
• Complicated cataract
• Vitreous hemorrhage
• Choroidal hemorrhage
• Strabismus fixed convergence

28. Thank you!