2. hyperopia / long-sightedness
• The term hypermetropia is derived from
hyper meaning “In excess”
met meaning “measure” &
opia meaning “of the eye”.
• First suggested in 1755 by KASTNER
• Later by DONDERS 1858 hyperopia
• HELMHOLTZ - hypermetropia
3. DEFINITION
• parallel rays of light coming from infinity are
focused behind retina with accommodation
being at rest
• The posterior focal point is behind the retina
which receives a blurred image
4.
5. ETIOLOGY
1) AXIAL
• Most common
• Total refractive power of eye is normal
• Axial shortening of eyeball (<2mm)
• 1mm short- 3 D of HM
• Physiologically >6D HM are uncommon
• At birth +2.5 – 3 D of HM (physiologically)
• Pathologically seen in cases like orbital
tumour, inflammatory mass , oedema,
coloboma and microphthalmos.
6. 2) CURVATURAL
• Flattening of cornea, lens or both
• 1mm increase in roc - 6D of HM
• Never exceed 6D HM physiologically
• Congenitally flattened (cornea plana)
• Result (trauma and disease )
3) INDEX
• Change in refractive index with age
• Physiologically in old age
• Pathologically in diabetics under treatment
7. 4)POSITIONAL
• Posteriorly placed crystalline lens
• Occurs as congenital anomaly
• Result of trauma or disease
5)ABSENCE OF LENS
• Seen in aphakia
9. SIMPLE HYPERMETROPIA
• Commonest form
• Results from normal biological variations in
the development of eyeball
• Include axial and curvatural HM
• May be hereditary
10. PATHOLOGICAL HYPERMETROPIA
• Anomalies lie outside the limits of biological
variation
• Acquired hypermetropia
– Decrease curvature of outer lens fibers in old age
– Cortical sclerosis
• Positional hypermetropia
• Aphakia
• Consecutive hypermetropia
11. FUNCTIONAL HYPERMETROPIA
• Results from paralysis of accommodation
• Seen in patients with 3rd nerve paralysis &
internal ophthalmoplegia
12. OPTICAL CONDITION
• Parallel rays focus behind retina
• Diffusion circles produce blurred & indistinct
images
• Retina is nearer to nodal point
• Image is smaller than in emmetropic
• Rays diverge from retina
• Formation of clear image is possible only
when converging power of eye is increased
16. TOTAL HYPERMETROPIA
• It is the total amount of refractive error,
estimated after complete cycloplegia with
atropine
• Divided into latent & manifest
17. LATENT HYPERMETROPIA
• Corrected by inherent tone of ciliary muscle
• Usually about 1D
• High in children
• Decreases with age
• Revealed after abolishing tone of ciliary
muscle with atropine
18. MANIFEST HYPERMETROPIA
Correct by accommodation and convex lens
FACULTATIVE HYPERMETROPIA
• Corrected by patients accommodative effort
ABSOLUTE HYPERMETROPIA
• Residual part not corrected by patients
accommodative effort
20. NORMAL AGE VARIATION
At birth +2 +3D HM
• Slightly increase in one year of life,
• Gradually diminished
In old age after 50 year again tendency to HM
1) Lens grows, converging power decreases
2) Change in refractive index
Some amount of latent HM become manifest
More amount of facultative HM become absolute
Practically after 65 year all of it become absolute
21. SYMPTOMS
• Principal symptom is blurring of vision for
close work
• Symptoms vary depending upon age of
patient & degree of refractive error
ASYMPTOMATIC
• small error produces no symptoms
• Corrected by accommodation of patient
22. ASTHENOPIA
• Refractive error are fully corrected by
accommodative effort
• Sustained accommodation produces symptoms
• Asthenopia increases as day progresses
• Increased after prolonged near work
SYMPTOMS
Tiredness
Frontal or fronto temporal headache
Watering
Mild photophobia
23. DEFECTIVE VISION WITH ASTHENOPIA
• Not corrected by accommodation
• Defective vision for near more than distance
• Asthenopia due to sustained accommodation
• Refractive error more(>4D)
24. DEFECTIVE VISION ONLY
• Refractive vision more than 4D
• Adults usually do not accommodate
• Marked defective vision for near and distance
25. SIGNS
• VISUAL ACUITY : Defective
• EYEBALL: small or normal in size
• CORNEA : may be smaller than normal. There
can be CORNEA PLANA
• ANTERIOR CHAMBER : may be shallow
• LENS: could be dislocated backwards
• A Scan ultrasonography (biometry) reveal
short axial length
26. FUNDUS:
A) DISC: Dark reddish color, irregular margins
,confused with Papillitis so termed as
PSEUDO-PAPILLITIS
B) MACULA: Situated further from the disc
than usual, large positive angle alpha,
apparent divergent squint
C) BLOOD VESSELS: Show undue tortuosity &
abnormal branchings
D) BACKGROUND: SHOT- SILK RETINA
27. COMPLICATION
• Recurrent styes , blepharitis or chalazia
• Accommodative convergent squint
• Amblyopia
– Anisometropic
– Strabismic
– Uncorrective bilateral high hypermetropia
• Predisposition to develop primary narrow
angle glaucomas
Care should be taken while instilling mydriatics
29. Young children(<6 or 7yrs)
Some degree of hypermetropia is
physiological so no correction
Treatment required if error is high or
strabismus is present
working in school small error may require
correction
refraction should be carried out every six
month
30. ADULTS
If symptoms of eye-strain are marked,we
correct as much of the total hypermetropia as
possible,trying as far as we can to relieve the
accommodation
Some patients with hypermetropia do not
initially tolerate the full correction indicated
by manifest refraction so we undercorrect
them
Exophoria hyperopia should be under correct
by 1 to 2D
31. Patients with absolute hypermetropia are
more likely to accept nearly the full correction
because they typically experience immediate
improvement in visual acuity
In pathological hypermetropia the underlying
cause rather than the hypermetropia is chief
concern
36. REFRACTIVE SURGERY
• Refractive surgery is not as effective as in
myopia
TYPES:
1) HEXAGONAL KERATOTOMY
2) LASER THERMAL KERATOPLASTY
3) PHOTOREFRACTIVE KERATECTOMY
4) LASER IN SITU KERATOMILEUSIS(LASIK)
5) PHAKIC IOL AND CLEAR LENS EXTRACTION
37.
38. LASER THERMAL KERATOPLASTY(LTK)
• Procedure done using laser energy to heat the
cornea (contraction of collagen) and increase
its curvature
• Central heating of cornea results in central
corneal flattening thereby resulting in
hyperopic shift
40. LASER IN SITU KERATOMILEUSIS(LASIK)
• Anterior flap of cornea lifted with keratome
and excimer laser is used to sculpt the stromal
bed to change the refractive error of eye
• It can correct up to 4D of hypermetropia and
8D of astigmatism
41. PHAKIC IOL AND CLEAR LENS
EXTRACTION
• Done by Phaco technique
• Clear lens extraction with the implantation of
an IOL-----Preferably foldable IOL or a
Piggyback IOL is implanted
42. VISUAL HYGIENE
• While reading or doing intensive near work
take a break about every 30 min
• When reading maintain proper distance that is
the book should be at least as far from your
eyes as your elbow when you make a fist and
hold it against your nose
• Sufficient Illumination
• Place a limit spent watching television &
watching videogames
• Sit 5-6 feet away from the television
43. • Younger children who have significant
hyperopia associated with amblyopia,
strabismus,or anisometropia require
treatment, starting as early as 3-6 months of
age
44. BIBLIOGRAPHY
1) DUKE – ELDER’S PRACTICE OF REFRACTION
2) OPTICS AND REFRACTION BY KHURANA
