The corneal diseases are one of the leading causes of blindness in the world. in most cases, these infections are preventable or treatable. This seminar provides an overview of the anatomy and physiology of the cornea, as well as an overview of common conditions.

1. RN. ABDELRAHMAN AMER
RN. SAAMER ALAMOODY
2014

2. ‫الرحمن‬ ‫ا‬ ‫بسم‬
‫الرحيم‬

4. introduction
The corneal diseases are one of the leading causes of
blindness in the world. in most cases, these infections
are preventable or treatable.
This seminar provides an overview of the anatomy and
physiology of the cornea, as well as an overview of
common conditions.

6. Anatomy
The cornea is a highly specialised structure which
possesses the following vital functions:
 a clear refractive interface,
 tensile strength,
 and protection of the intraocular contents from
the external environment.
It has an elliptical shape with the dimensions 10.6
mm vertically and 11.7 mm horizontally

7. the cornea consists of five layers

8. 1 Epithelium :
consisting of five or six layers of epithelial cells,
which are continues with the conjunctival
epithelium. The basement membrane is the
innermost layer of the epithelium .
The epithelium is the only layer of the cornea
that regenerates following trauma.

9. 2 Bowman’s layer:
a thin homogeneous layer which servesas a base
for the epithelial anchoring system. Once
destroyed, this layer is never replaced. Its
absence indicates previous trauma or
ulceration.

10. 3 Stroma:
This comprises 90% of the cornea , and is
composed of parallel connective tissue .
4 Descemet’s membrane:
Athin elastic membrane possessing high tensile
strength and containing proteoglycans and
glycoproteins in addition to collagen.

11. 5 Endothelium:
This comprises a single layer of endothelial
cells, which are metabolically active,
and their primary function is the control
of stromal hydration.
The endothelium elongates when damage.

12. Function of the Cornea
The cornea shields the rest of the eye from dust, germs
and other harmful foreign matter. It also controls and
focuses incoming light but contains no blood vessels
to nurture or protect it against infection.
• Protection.
• Refraction.
• Transmission of light

13. MICROBIAL KERATITIS
• BACTERIAL INFECTIONBACTERIAL INFECTION
• FUNGALE INFECTIONFUNGALE INFECTION
• VIRAL INFECTIONVIRAL INFECTION
• PARASITIC INFECTIONPARASITIC INFECTION

14. BACTERIAL INFECTIONBACTERIAL INFECTION
Most common microorganism/
• Staphylococci G+
- aureus
- epidemidis
• streptococci G+
- pneumoniae
- pyogenes
• Pseudomonas aeruginosa
• Neisseria

15. Signs and symptoms
 painful red eye with a localised abscess
in the cornea
accompanied by stromal ulceration
should arouse clinical suspicion.
 There may be an acute uveitis with
hypopyon.
Photophobia.

16. Diagnosis
Clinical history.
Physical examination.
Cultures of corneal scrapings (for
identification the organism)
Corneal biopsy .

18. Treatment
Hospitalization
Topical administration (rout of
choice)
Subconjuntival injection .
I.V antibiotic .
Oral antibiotics (low efficacy)

20. FUNGALE INFECTIONFUNGALE INFECTION
A fungal keratitis is an
inflammation of the eye's cornea that
results from infection by a fungal
organism.

21. Symptoms of Fungal Keratitis
Symptoms of fungal keratitis include:
Eye pain and redness
Blurred vision
Sensitivity to light
Excessive tearing or discharge
If you experience any of these symptoms, remove your
contact lenses (if you wear them) and call your eye
doctor right away. Fungal keratitis is a very rare
condition, but if left untreated, it can become serious
and result in vision loss or blindness.

22. Riske factors
Fungal keratitis most commonly occurs in tropical and
sub-tropical regions of the world. In temperate areas
of the world, risk factors for developing fungal
keratitis include:
Recent eye trauma.
Underlying ocular (eye) disease.
Weakened immune system.
Contact lens use.

23. Fungal Keratitis Diagnosis
History.
Physical examination.
culture from corneal scrapings is
considered to be the standard for
definitive diagnosis of fungal keratitis.

24. Fungal Keratitis

25. Treatment for Fungal Keratitis
Fungal keratitis must be treated with prescription antifungal
medicine for several months.
 Natamycin is a topical ophthalmic antifungal medication that
works well on superficial corneal infections, particularly those
caused by filamentous fungi such as Aspergillus and
Fusariumspecies.
 However, corneal infections that are deeper and more severe
usually require treatment with systemic antifungal medication
such as amphotericin B, fluconazole, or voriconazole. Patients
who do not get better after topical and oral antifungal
medications may require surgery, including corneal
transplantation.

26. VIRAL INFECTIONVIRAL INFECTION
Herpes simplex Herpes zoster
The DNA viruses, herpes simplex and herpes zoster,
are the commonest viral infections of the cornea.

27. Herpes simplex
Clinical presentation
Primary infection
usually in children, involving the eyelids and
lips. Corneal involvement is rare. A minor
follicular conjunctivitis may occur.

28. Recurrent infection
1 Acute stage:
a unilateral painful red eye with superficial
ulceration taking the form of club shaped
finger-like processes (dendritic /dendritiform).
Fluorescein stains the epithelial defect and
Rose Bengal identifies dead epithelial cells
along the edge of the defect.

29. 2 Chronic stage:
the disease may progress to ulceration,
scarring, or perforation.

30. Symptoms:
• Red eye.
• Pain.
• Photophobia.
• Epiphora (tearing).
• History of previous episodes.
• May complain of blurred vision.

31. Diagnosis
Assess visual acuity.
Examine lids and conjunctiva for evidence of
inflammation. Involvement here is less common in
secondary infection although conjunctival injection
(red eye) is almost universal. There may be erosions
around the lid margin with the presence of small
vesicles or pustules.
Observe cornea: any opacities or haziness? This may
suggest stromal involvement.
Test corneal sensation this can be reduced in
epithelial disease.
Stain the cornea and look for evidence of ulcers by
staining with fluorescein.

33. Treatment
 Antiviral medications including:
acyclovir (the drug of choice )
trifluridine, vidarabine, and idoxuridine.
Steroids in chronic oedema.
 keratoplasty for perforations and
scarring.

34. Herpes zoster
The pathological features of herpes
zoster infection of the cornea are
very similar to those described for
chronic.

35. PARASITIC INFECTIONPARASITIC INFECTION
Various parasitic infections are important
causes of ophthalmic diseases worldwide.
Most parasitic infections are spread by
insect vectors or consuming or getting
contact with contaminated water

36. Various organisms producing
keratitis are the following:
Acanthamoeba
Microsporidia
Onchocerca
Leishmania-
Trypanosoma bruci

37. The pathogenic species of Acanthamoeba known to
produce keratitis are the following
1. A castellani
2. A polyphaga
3. A hatchetti
4. A culberstoni
5. A rhysodes
6. A griffina

38. Acanthamoeba keratitis
Acanthamoeba was first established as a case
of human disease in 1973
This vision threatening corneal disease was
first recognized in contact lens wearers.
There was a sharp increase in the
recognition(and perhaps incidence ) of this
disease in the late 1980’s.
First case of Acanthamoeba keratitis from
India was reported in 1987 from Aravind Eye
Hospital, Madurai

39. Clinical signs
 are discussed in three stages
1. Early stage / Epithelial defects, epithelial haze
pseudodendrites
2. Late stage / Epithelial defects, stromal infiltrates,
nummular keratitis
3. Advanced stage/ Ring infiltrate, satellite lesions,
stromal abscess

40. Other features
- Severe anterior and posterior uveitis
- Nodular or Diffuse scleritis
- Corneal stromal infiltrates (single,multiple,ring shape)
- Anterior uveitis (transient hypopyon)
- Radial keratoneuritis
- Disciform keratitis

42. Clinical characteristics that help to
distinguish Acanthamoeba keratitis from
other keratitis include the following:
1. Ring infiltrate
2. Elevated epithelial lesion
3. Relative lack of vascularisation even in chronic
and severe cases

43. Treatment
There is no consensus on treatment.
Various regimens are described.
Treatment is required for 6-12 months.
 Prolonged medication results in corneal
vascularisation and toxic keratitis.

44. NURSING CARE FOR
KERATITIS

45. Nursing Diagnosis for Corneal infiction
a. Anxiety related to damage to sensory and lack of
understanding of post-operative care, drug
delivery.
Nursing interventions:
- Assess the degree and duration of visual
impairment
- Orient the patient to the new environment
- Describe the routine perioperative
- Encourage to perform daily living habits when able
- Encourage the participation of the family or the
people who matter in patient care.

46. b. Risk for Injury related to damage vision.
Nursing interventions:
- Help the patient when able to do until a stable
postoperative ambulation
- Orient the patient in the room
- Discuss the need for the use of metal shields or goggles
when necessary
- Do not put pressure on the affected eye trauma
- Use proper procedures when providing eye drugs

47. c. Acute Pain related to trauma, increased IOP,
surgical intervention or administration of
inflammatory eye drops dilator.
Nursing interventions:
- Give the medication to control pain and the IOP as
prescribed
- Give cold compress on demand for blunt trauma
- Reduce lighting levels
- Encourage use of sunglasses in strong light

48. d. Risk for self-care deficit related to damage
vision.
Nursing interventions:
- Give instructions to the patient or the people closest to
the signs and symptoms, complications should be
immediately reported to the doctor.
- Provide verbal and written instructions to patients
and the right means of technique in delivering drugs
- Evaluate the need for assistance after discharge
- Teach patients and families of sight guidance
techniques