A 20-year-old Saudi female presented with progressive gradual loss of vision in both eyes over two years. Examination found VA of 6/9 in the right eye and 6/18 in the left. Signs of keratoconus were seen including stromal thinning, Vogt's striae, and Munson's sign. Topography showed patterns characteristic of keratoconus such as inferior steepening and asymmetric bowtie patterns. She was diagnosed with keratoconus stage 2 based on findings. Contact lenses were recommended for management as spectacles could not adequately correct her vision.

2. case
• 20 years old saudi female come to outpatient
clinic in KFH & file # 36034723 complaining of
progressive gradual loss of vision in the both
eyes for two years.. she said that ( the glasses
didn't fix the problem and I've changed it
many times ) .. she denied any history of
trauma .. there were no history of diabetes
nor HTN ..

3. Examination :
on examination :-
VA 6/9 OD ( right ) .
6/18 OS ( left ).
IOP was 17 mmHg in both eyes .
External sign ( Munson's sign ) .
SLE : 1- stromal thinning
2- Vogt's striae
Ophthalmoscope shows oil droplet sign .
Funduscopy appeared normal.

4. differential diagnosis
• Astigmatism
• Myopia
•

5. management
• Contact lens because he still on stage 2

7. Anatomy of cornea:
• The cornea is the transparent, dome-shaped
or Prolate which is flatter in the periphery
and steeper centrally & its window covering
the front of the eye. It is a powerful refracting
surface, providing 2/3 of the eye's focusing
power.
• Average size:
11mm vertically
12mm horizontally

8. histology

9. Definition
“Keratoconus” is a medical term used to
describe a condition in which the cornea
assumes a conical shape because of thinning
and protrusion.

10. Keratoconus
• Keratoconus (KC) is a progressive,
noninflammatory, bilateral (but usually
asymmetrical) ectatic corneal disease,
characterized by paraxial stromal thinning and
weakening that leads to corneal surface
distortion(forming conical shape) induces
irregular astigmatism, myopia and protrusion
leading to mild to moderate impairment in the
quality of vision.

11. Histopathology
• Inherited ectatic disorder leading to reduction of
corneal thickness
Characterized by:
- Extreme corneal thinning.
- Focal defects in epithelial basement
membrane and Bowmans’ layer.
( Pathognomonic)

12. Clinical Presentation
• The earliest Symptoms
blurring of vision ( 10Y – 30Y)
Changing eye glass prescription
Uncorrectable vision to 20/20
with glasses

13. Evaluation and diagnosis of keratoconus
History and family history
Follow up evaluation
Slit -lamp exams
Keratoscopy- Keratometry
Corneal thickness - pachymetry
Topography - Orbscan –Pentacam

14. Signs / Symptoms
• KC often results in irregular astigmatism which can
severely limit distance and night vision in a way that
can not always be corrected using glasses
• Ghosting/ monocular diplopia
• Glare at night
• Haloes around lights
• Blurred/ distorted vision

15. Signs / Symptoms
• KC often results in irregular astigmatism which can
severely limit distance and night vision in a way that
can not always be corrected using glasses

16. Signs / Symptoms
• Frequently changing spectacle Rx and axis of astigmatism
• Poor repeatability of subjective refraction
• Ghosting/ monocular diplopia
• Glare at night
• Haloes around lights
• Blurred/ distorted vision
• Scissors reflex: (swirling retinoscopy reflex)
• Distorted/ irregular keratometer mires with steep readings
• Prominent corneal nerves

17. Detection of Keratoconus
1. Retinoscpy
2. Slit lamp
3. Keratometry
4. Keratoscpy
Vogt’s striae
fleisher’ ring

18. SIGNS OF KCN
• External signs :
– Munson” sign
– Rizzuti phenomenon
• Slit-lamp findings:
– Stromal thining
– Posterior stress lines(vogt,s striae)
– Iron ring ( fleischer ring )
– Scarring - epithelial or subepithelial
• Retroillumination signs:
– Scissoring on retinoscopy
– Oil droplet sign (charleaux”)

19. Signs of KC
• High irregular astigmatism
• External signs :
– Munson’s sign
– Rizzuti phenomenon
Sharply focused beam of light near the nasal
limbus ,produced by lateral illumination of the
cornea in patients with advanced keratoconus

20. Signs of KC Slit-lamp findings
– Stromal thinning
A hallmark, occurs at the apex of the cone
(the point of maximal protrusion)
:

21. Posterior stress lines
(Vogt,s striae)
• Fine vertical lines in the deep stroma, just
anterior to descemet,s membrane that parallel
the axis of the cone and disappear transiently
on gentle digital pressure

22. Corneal Scarring
epithelial or subepithelial
• Superficial linear scars at the corneal apex
• These results from ruptures in bowman,s layer

24. Iron ring ( fleischer ring )
• The ring is a partial or complete annular line
commonly seen at the base of the cone
• The ring is formed from hemosiderin pigment
deposited in the basal epithelium

25. Retroillumination and
retinoscopy signs
• Scissoring on retinoscopy
• Oil droplet sign (charleaux”)

26. Corneal hydrops
•Acute descemet membrane rupture and corneal
hydrops it will led to the deranges of Aq. Humor
inside the cornea

27. Risk Factors
• Uncontrolled ocular surface allergic disease
• Chronic rubbing of the eyes
• ocular associations
– vernal keratoconjunctivitis
– retinitis pigmentosa
• systemic associations
– connective tissue disorders
(eg, Ehlers-Danlos and Marfan syndromes)
– mitral valve prolapse
– Atopic dermatitis
– Down syndrome.

28. Computerized Corneal Topography
• Corneal topography is
the method by which
the corneal shape,
curvature, power, and
irregularities are
measured

29. Computerized Corneal Topography
• Corneal topography provides:
 The Axial Curvature Map.
 Describe the Shape and Power
including the central 1-2 mm
 The Elevation Maps.
 The Pachymetric Map.
 Quantitative Indices

30. Keratoconus
• Localised inferiorly displaced steepness
• Keratoconus suspect
– K > 47.2
– I-S > 1.4
• Clinical keratoconus
– K > 48.7
– I-S > 1.9

31. How to reade am mape
• be sure you are reading for same Pt & be sure
File # & age & sex & this map for whice eye
• green colure is near to normal Yellow is
boredr line and red in like patches its is hot
spote
• Focus on avery map alone
• Put one point & strata reading

32. Anterior Map

33. Posterior Map

34. Keratometric Map

35. Pachemetry Map

36. Keratoconus pattern
non-Keratoconus cornea
general symmetry overall
with no exsessive steepening
Keratocunus cornea
extreme asymmetrical
and inferior steepening

37. Abnormal Topography

38. Topographic patterns of keratoconus
 Inferior steepening without bowtie pattern
specially more prominent temporally
 Asymmetrical bow tie (AB)
& inferior/superior steepening(IS-SS)
 Central steepening +/- superimposed with
asymmetrical bowtie pattern
 symmetric bow tie (AB) &
skewed radial axes (SRAX)

40. Topographic patterns of keratoconus

41. Topographic patterns of keratoconus

42. Topographic patterns of keratoconus
 Inferior steepening without bowtie pattern
specially more prominent temporally
 Asymmetrical bow tie (AB)
& inferior/superior steepening (IS-SS)
 Central steepening +/- superimposed with
asymmetrical bowtie pattern
 Asymmetic /symmetric bow tie (AB) &
skewed radial axes (SRAX)

43. Keratoconus pattern:
Inferior steepening without bowtie pattern
specially more prominent temporally

44. Keratoconus pattern:
asymmetrical bow tie (AB)
& inferior steepening(IS)

45. Keratoconus pattern:
asymmetrical bow tie (AB)
& superior steepening(SS)

46. Keratoconus pattern:
Central keratoconus
central unusual steepening without bow tie

47. Keratoconus pattern:
Central steepening, superimposed with asymmetrical bowtie-
slightly irregular astigmatism asymmetrical central hourglass

48. Globus topographic type of KCN

49. Keratoconus pattern:
Symmetic(SB) /asymmetric bow tie (AB) &
(SRAX)

50. Keratoconus pattern:
asymmetrical bow tie &
skewed radial axes (AB/SRAX)

51. Keratoconus pattern:
symmetrical bow tie &
skewed radial axes (AB/SRAX)

52. Grading of keratoconus according to
amsler krumeich classification:
Stage I
• Eccentric steeping
• Myopia and astigmatism < 5.00 D
• Mean central K readings < 48.00 D
Stage II
• Myopia and astigmatism from 5.00 to 8.00 D
• Mean central K readings < 53.00 D
• Absence of scarring
• Minimum corneal thickness >400 μm.

53. Stage III
• Myopia and astigmatism from 8.00 to 10.00 D
• Mean central K readings >53.00 D
• Absence of scarring
• Minimum corneal thickness 300 to 400 μm.
Stage IV
• Refraction not measurable
• Mean central K readings >55.00 D
• Central corneal scarring
• Minimum corneal thickness 200 μm

54. treatment
• Spectacles—in stage 1
• Contact lens in stage 1;2 and 3(hard lenses)
• Photothrapeutic keratotomy.(in advanced kc)
• Intrastromal corneal rings.
• Corneal collagene cross linking . (stage 1;2)
• Phakic intraocular lenses.(stage1)
• Keratoplasty. (mainly in stage 4)

56. END
Prof. M.Barbary