ophthalmology

2. DR SALMAN AHMAD
PG Trainee Ophthalmology
SERVICES HOSPITAL LAHORE
CHEMICAL INJURIES TO EYES &
MANAGEMENT

3. Background & Introduction
 True ocular emergency
 Potentially blinding ocular injuries
 Chemical burns
 Alkaline agents
 Acidic agents
 Thermal burns
 Firework explosions
 Steam
 Boiling water
 Molten metal

4. ALKALINE BURNS
 Alkali dissociates into a hydroxyl ion and a cation
in the ocular surface
 Hydroxyl ion saponifies cell membrane fatty acids
 Cation interacts with stromal collagen and
glycosaminoglycans leads to deeper penetration
into cornea & AC.
 Hydration of glycosaminoglycans….. Stromal
haze
 Collagen hydration…. Fibril distortion &
shortening….. Trabecular meshwork
alterations…. Increased IOP
 Inflammatory mediators cause release of
prostaglandins…… further increase IOP

5. Common alkali substances at home

6. ACIDIC BURNS
 Acid dissociates into hydrogen ion & anions
 Hydrogen ions damage ocular surface by altering
the pH
 Anions cause protein denaturation, precipitation
and coagulation
 Protein coagulation prevents deeper penetration
& responsible for ground glass appearance of
corneal stroma.

7. Common acidic substances at home

8. Severity of burn
 Severity of burn depends on
 Surface area of contact
 Depth of penetration, concentration, time of contact, time
of interference.
 Degree of stem cell injury
 Common area of damage in eye
 Anterior segment
 Cornea
 Conjuctiva
 Lens
 Deeper than cornea
 Cataract
 glaucoma

9. Pathophysiology of ocular injury
 Necrosis of corneal & conjuctival epithelium
 Loss of limbal stem cells
 Conjuctivalization and vascularization of the corneal
surface
 Persistent corneal epithelial defects with sterile corneal
ulceration & perforation
 Ocular surface wetting disorder
 Symblepharon formation
 Cicatricial entropion
 Corneal opacification
 Ciliary epithelial damage… ascorbate production
 Hypotony & phthisis bulbi

10. Pathophysiology of ocular injury
 Healing
 Epithelium
 Migration of cells from limbal stem cells
 Stroma
 Damaged stromal collagen is phagocytosed by keratocytes
& new collagen synthesized

11. Diagnosis
 Diagnosis is made from the history
 The staging is guided by the clinical picture.
 Intraocular structures in the anterior segment of
the eye can also be involved and can be
associated with lens opacities and secondary
glaucoma.

12. Severe chemical injury

13. Severe acid burn

14. Acute alkali burn

15. Severe alkali burn

16. Corneal opacity of lime burn

17. Alkali injury
 ‘cooked fish eye’
 Cornea white as chalk
and opaque
 Superficial and deep
vascularization

18. Alkali injury
 Heavily vascularized
cornea with
symblepharon
 Poor prognosis
expected for
penetrating
keratoplasty

19. Chemical injury
Total destructive effect
of lye burn Superglue injury

20. Clinical picture
Symptoms Signs
 Pain
 Lacrimation
 Photophobia
 Blepharospasm
 Blurring of vision
 Eyelid edema
 Chemosis
 Conjuctival injection
 Corneal abrasion

21. Effects of ocular surface burn
structure Immediate effect Delayed effect
Lid Oedema
Dermatitis
Ulcer
Cicatricial entropion
Cicatricial ectropion
Conjuctiva Conjuctival injection
Ulcer
Chemosis
Symblepharon
Xerosis
Pseudopterygium
Cornea Oedema
Ulcer
Perforation
Vascularized opacities
Xerosis
Uvea Anterior uveitis Iridocyclitis
IOP May be increased Increased (conjuctival
fibrosis)

22. Roper-Hall classification system
Grade Prognosis Limbal ischemia Corneal
involvement
I Good None Epithelial damage
II Good < 1/3 Haze, but iris
details visible
III Guarded 1/3 to 1/2 Total epithelial
loss with haze
that obscures iris
details
IV Poor > 1/2 Cornea opaque
with iris and pupil
obscured

23. A new classification of ocular burns
Grade Prognosis Clinical
findings
Conjuctival
involvement
I Very good 0 clock hours
of limbal
ischemia
0 %
II Good 3 clock hours
of limbal
ischemia
30%
III Good >3-6 clock
hours of
limbal
ischemia
> 30-50%
IV Good to
guarded
> 6-9 clock
hours of
limbal
ischemia
> 50-75%
V Guarded to
poor
>9-<12 clock
hours of
limbal
> 75 - <100%

24. Complications
 Primary complications
 Conjuctival inflammation
 Corneal abrasions
 Corneal haze and edema
 Acute rise in IOP
 Corneal melting & perforation
 Secondary complications
 Secondary glaucoma
 Secondary cataract
 Conjuctival scarring
 Corneal thinning & perforation
 Complete ocular surface disruption
 Corneal ulceration (sterile or infectious)
 Phthisis bulbi
 Complete cicatrization of corneal surface

25. Laboratory study
 The pH of ocular surface should be periodically
tested. Irrigation should be continued until the pH
reaches neutrality.
 No other tests are generally necessary unless
other systemic injuries are concurrent.

26. Goals of Medical care
 Removing of offending agents
 Promoting ocular surface healing
 Controlling inflammation
 Preventing infection
 Controlling IOP

27. Immediate management of
chemical burns

28. Removal of inciting chemical
 Immediate copious irrigation
 Normal saline solution
 Ringer’s lactate solution
 Normal saline with bicarbonate
 Balanced salt solution (BSS)
 Irrigation continued until pH is neutralized

29.  Evert the upper eyelid and irrigate, and irrigate
the lower eyelid
 Check pH with litmus paper
 If litmus paper not available then continue
irrigation for 20 minutes
 Contraindications for water… burns with
chemicals of heavy metals

31. Eye irrigation

32. Transfer
 After completing initial irrigation and treatment,
patient should be transferred to facilities that have
ophthalmologists available to assume care for
them.

33. Acute management of chemical
burns

34. Acute management
 Eye speculum
 Topical anesthesia
 Eversion of eyelids
 Continue irrigation till
pH is normalized

35. Promote ocular surface healing
1. Remove inciting chemical
2. Debridement
3. Paracentesis
4. Early assessment followed by
1. Artificial tear supplement…
2. Ascorbate --- > improvement in corneal healing
3. Therapeutic bandage contact lens
4. Amniotic membrane transplant

36. Mid term management of
chemical burn

37. Control of inflammation
 Topical steroids
 Citrate
 Acetylcysteine 10%
 Ascorbate and citrate

38. Control of infection & cicatrization
 Topical antibiotic,
aggressive lubrication
with eye ointments
(steroid-antibiotic
combination)
 Prophylactic
antibiotics

39. Control of IOP
 Oral acetazolamide or topical beta-blockers or
aqueous suppressant are advocated to reduce
IOP.

40. Control of pain
 Cycloplegics for ciliary
spasm
 Oral pain medications

41. Improves healing
 Steroids reduce inflammation and neutrophil
infiltration
 Ascorbic acid synthesis of mature collagen
 Citric acid inhibitor of neutrophil activity
 Tetracycline inhibitor of collagenase

42. Delayed management of
chemical burns

43. 1. Correction of lid deformity
2. Conjuctival or mucous membrane graft
3. Amniotic membrane transplantation
4. Limbal stem cell transplantation
5. Penetrating keratoplasty
6. Keratoprosthesis

44. 1. Correction of lid deformity
 Cicatricial entropion or ectropion correction
surgery

45. 2. Conjuctival or mucous membrane
graft

46. 3. Amniotic membrane
transplantation

47. 4. Limbal stem cell
transplantation
A. Removal of pannus
& superficial
keratectomy
B. Cicatrix removed
C. 3 to 5 mm superior
& inferior conjuctival
stem cells
D. Keratectomy 1 mm
within the limbus
with 5mm conjuctiva

48. 5. Penetrating keratoplasty

49. Summary of suggested action during
the late periods
 Tear film should be augmented
 Lysis of symblephra and reconstruction of
fornices
 Correction of cicatricial entropion and trichiasis if
keratoplasty is anticipated
 Penetrating keratoplasty

50. Inpatient & outpatient
medications
 Prednisolone acetate 1% (qid)
 Erythromycin ophthalmic ointment (4-8 times/
day)
 Homatropine 5% or Scopolamine 0.25% (tid)
 Ascorbate 500 mg P/O qid
 Levobunolol 0.5% bd or acetazolamide 250 mg
tid if IOP > 30 mmHg
 Excessive lubricants

51. Prevention
 Education and training
 Safety goggles at chemical workplace

52. Prognosis
 Directly related to severity of insult
 Grading according to prognosis as in Roper Hall
classification

53. Differential diagnosis
 Conjuctivitis, acute hemorrhagic/ allergic
 Corneal abrasion
 Corneal erosion, recurrent
 Corneal foreign body
 Keratoconjuctivits sicca
 Corneal ulcer

54.  Chemical injuries are actually the true ocular
emergencies and don't waste time & defer the
detailed history and examination till the
appropriate irrigation has been achieved.

55. Thank you