• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Management of ocular chemical injuries
 

Management of ocular chemical injuries

on

  • 3,179 views

 

Statistics

Views

Total Views
3,179
Views on SlideShare
3,179
Embed Views
0

Actions

Likes
1
Downloads
178
Comments
0

0 Embeds 0

No embeds

Accessibility

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

CC Attribution License

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Management of ocular chemical injuries Management of ocular chemical injuries Presentation Transcript

    • Management of Chemical Injury to Eye ASSIGNMENT OF OPHTHALMOLOGY BY: DR.AFIQAH BINTI MUHAMED FAIZAL 4 TH Y E A R M E D I C A L S T U D E N T O F TANTA UNIVERSITY,EGYPT 2011/2012 THURSDAY,17/05/2012Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Background and Introduction of Management of Chemical Injuries in the Eye:Background & Introduction: Ocular burns constitute true ocular emergencies and both thermal and chemical burns represent potentially blinding ocular injuries. Thermal burns result from accidents associated with firework explosions, steam, boiling water, or molten metal (commonly aluminium). Chemical burns may be caused by either alkaline or acidic agents Chemical injuries to the eye represent one of the true ophthalmic emergencies. While almost any chemical can cause ocular irritation, serious damage generally results from either strongly basic (alkaline) compounds or acidic compounds. Alkali injuries are more common and can be more deleterious. Bilateral chemical exposure is especially devastating, often resulting in complete visual disability. Immediate, prolonged irrigation, followed by aggressive early management and close long-term monitoring, is essential to promote ocular surface healing and to provide the best opportunity for visual rehabilitation.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Types of Chemical InjuriesALKALI BURNSAlkali burns are the most dangerous due to its rapid penetration through both theexternal structures like anterior chamber and cornea and the internal structureslike the lens. They combine with cell membrane lipids causing disruption of celland tissue necrosis. The higher the pH of chemical, the worsen the damage on eye.Common alkali substances contain:•Ammonia,NH3; a common ingredient in many household cleaning agentsAnd causing the most serious injury•Lye, NaOH; a common ingredient in drain cleaners and causing the mostSerious injury.•potassium hydroxide,KOH•magnesium hydroxide,Mg[OH]2•Lime, Ca[OH]2; the most common cause, which fortunately does notinflict as much damage as rapidly penetrating alkalies do.Common alkali substances at home that contain these chemicals include:•fertilizers•cleaning products (ammonia),•drain cleaners (lye)•oven cleaners•and plaster•cement (lime) Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Common alkali substance at home Lye  Lime  Ammonia(household cleaning agents containing ammonia)Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Types of Chemical InjuriesACID BURNSAcid burns result from chemicals with a low pH and are usually less severe than alkaliburns because they do not penetrate into the eye as readily as alkaline substances. Theexception is a hydrofluoric acid burn, which is as dangerous as analkali burn. Acids usually only cause damage on:Common acids causing eye burns include:•Sulphuric (H2SO4; the most common cause: an ingredient inautomobile batteries)•Sulfurous (H2SO3)•Hydrofluoric (HF; rapidly penetrating and causing the mostserious injuries)•nitric acid•Acetic acid (CH3COOH)•Chromic acid (Cr2O3)•Hydrochloric acid (HCl)Common alkali substances at home that may contain thesechemicals include:•glass polish (hydrofluoric acid)•vinegar•nail polish remover (acetic acid)Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Common acid substance at home Automobile batteries  Vinegar Glass polish  Nail polish removerAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Types of Chemical InjuriesIRRITANTSIrritants are substances that have a neutral pH and tend to cause morediscomfort to the eye than actual damage. -Most household detergents fall into this category. -Pepper spray is also an irritant. It can cause significant pain but usually does not affect vision and rarely causes any damage to the eye.The severity of ocular injury depends on:•Surface area of contact•Depth of penetration depends on:•Concentration of chemicals•Time of contact between chemical trauma into first aid•Time of interference•Degree of limbal stem cell injuryAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Severity of Burn1- The severity of a burn depends on:• Surface area of contact.• Depth of penetration: concentration, time of contact, time of interference.• Degree of limbal stem cell injury.2-Common area of damage in eye: Anterior segment of the eye Internal segment of the eye Cornea Conjunctiva Lens3-Deeper than the cornea are the most severe causing: cataracts glaucomaAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • PATHOPHYSIOLOGY OF OCULAR INJURES1-Damage by severe chemical injuries occurs  Anterior chamber penetration results in in the following order: iris and lens damage. Necrosis of the conjuntival and  Ciliary epithelial damage impairs corneal epithelium with disruption and secretion of ascorbate which is required occlusion of the limbal vasculature. for collagen production and corneal Loss of limbal stem cells may repair. subsequently result in  Hypotony and phthisis bulbi may conjuntivalisation and ensue. vascularisatioin of the corneal 2- Healing of the corneal epithelium and surface or persistent corneal stroma as follows: epithelial defects with sterile  The epithelium heals by migration of corneal ulceration and perforation. epithelial cells which originate from Other long_term effects include ocular limbal stem cells. surface wetting  Damaged stromal collagen is disorders, symblepharon formation phagocytosed by keratocytes and new and cicatricial entropion. collagen is synthesized. Deeper penetration causes breakdown and precipitation of glycosaminoglycans and stromal corneal opacification.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • N.B.- Although limbal ischaemia is usually associated with loss oflimbal stem cells, this is not always the case.- Transient ischaemia, or ischaemia occurring soon after theinjury but recovering in the ensuing days, may allow limbalstem cells to survive, recover or repopulate the affected sector.- Similarly, superficial “limbal involvement” can result in 360°of surface staining with deeper stem cells surviving. Thissituation may not become apparent until a few days after theinjury.- Because it is clinically not possible to evaluate this situationat the time of injury, it is proposed that the extent of limbalinvolvement at the time of injury, be based on the clock hoursof limbal staining observed.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Alkalies Acid More severe than acid burns due to: -Less severe than alkali burns.-Penetrate rapidly into eye ball (often in less than one -Acids quickly denature proteins in the cornealminute), through the cornea and anterior chamber. stroma, forming precipitates that retard additional penetration.-They combine with cell membrane lipids, -Causing localized damage due to its:mucopolysaccharides and to collagen, thereby resulting a)Coagulation effectin the disruption of the cells and necrosis of the tissues. b)Protein precipitations at epithelium levelOn the ocular surface, they saponify cell membranes andintercellular bridges, which facilitates rapid penetration -Leading to:into the deeper layers and into the aqueous and vitreous Physical barrier.compartments Buffering effect (Corneal tissue has an inherent buffering capacity that tends to equilibrate local pH to physiological levels, but severe chemical injuries-Necrosis of conjunctival blood vessel causing: exhaust the cellular and extracellular resources,“Cooked fish eye” the cornea is as white as chalk and allowing extremes of pH that are incompatible withopaque. tissue survival) Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Diagnosis- Diagnosis is made from the history.The staging is guided by the clinical picture.- Intraocular structures in the anterior segment ofthe eye can also be involved and can be associatedwith lens opacities and secondary glaucoma.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Severe Chemical burnAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Severe acid burn on eyeAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Acute alkali burn Acute alkali burn of greatest severity. Perilimbal blanching, chemosis, and corneal opacification are evident.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Severe alkali burn Acute alkali burn of severe degree. The eye rolled upward in avoidance (Bell phenomenon), exposing the lowest aspect of the cornea to the greatest damage.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Alkali burn(chemical burn) Corneal opacity following lime burn.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Alkali injury „cooked fish eye‟ following alkali injury. The cornea is white as chalk and opaque. There‟s superficial and deep corneal vascularization.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Alkali burnHeavily vascularized cornea with symblepharon several yearsafter severe chemical burn. Poor prognosis is expected forpenetrating keratoplasty.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Chemical burnOpaque vascularised cornea after severe chemicalburn.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Chemical burnChemical burn typically affecting cornea inferiorly.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Chemical injury- total destructive effect of  Superglue Injurya lye burnAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Chemical burn Following burn from hot  Alkali burn stage II aluminum:conjunctivaliza tion of the corneal surfaceAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Alkali burn stage III Alkali burn stage IIIAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Complication of Chemical injuryConjunctival adhesions  Symblepharon formationfollowing chemical injury following a chemical injuryAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Acid burn Acid burn with corneal erosion belowAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Severe Alkali BurnSevere alkali burn. A. Two weeks after injury: pannus begins to invade the opaque cornea from above. B. Three weeks after injury: pannus grows as the cornea begins to thin andclear. C. Seven weeks after injury: collagenolytic erosion and descemetocele in advance of the pannus. D. Eight weeks after injury: frank perforation of the cornea. Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Acid injury Mild acid injury Severe acid injury Scar from acid injuryAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Chemical burn on conjunctiva and cornea Alkali injury. When no corneal  Lime injury. Superficial and reepithelization had occurred deep corneal vascularization is by 4 weeks. present, and the eye is dry due to loss of most of the goblet cells.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Signs:• Clinical Pictures 1- Symptoms: 2- Signs: - Pain - eye lid edema, - Lacrimation - chemosis, - Photophobia - conjunctival injection - Blepharospasm - Diminution of vision - corneal abrasions Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Effects of Ocular Surface BurnAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Classification of ocular surface burnAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • A new classification of ocular surface burnsGrade Prognosis Clinical findings Conjunctival Analogue involvelment scaleI Very good 0 clock hours of 0% 0/0% limbal involvementII Good ⩽3 clock hours of ⩽30% 0.1–3/1–29.9% limbal involvementIII Good >3–6 clock hours of >30–50% 3.1–6/31–50% limbal involvementIV Good to guarded >6–9 clock hours of >50–75% 6.1–9/51–75% limbal involvementV Guarded to poor >9–<12 clock hours >75–<100% 9.1–11.9/75.1– of limbal 99.9% involvementVI Very poor Total limbus (12 Total 12/100% clock hours) conjunctiva involved (100%) involvedThe analogue scale records accurately the limbal involvement in clock hours of affected limbus/percentage ofconjunctival involvement. While calculating percentage of conjunctival involvement, only involvement ofbulbar conjunctiva, up to and includingFaizal Author& Disclosure:Dr.Afiqah Bt.Muhamed the conjunctival fornices is considered. in correspondence to other student in group
    • Complications1-Primary complications include the following: Conjunctival inflammation Corneal abrasions Corneal haze and edema Acute rise in IOP Corneal melting and perforations2-Secondary complications include the following: Secondary glaucoma Secondary cataract Conjunctival scarring Corneal thinning and perforation Complete ocular surface disruption with corneal scarring and vascularization Corneal ulceration (sterile or infectious) Complete globe atrophy (phthisis bulbi): See the image below.(phthisis bulbi=Shrinkage and atrophy of the eyeball followinga severe inflammation (e.g. uveitis), absolute glaucoma or trauma.) Complete cicatrization of the corneal surface following chemical injury.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Complications1- Eye lid:- trichiasis, madarosis, symblepharon, ankyloblepharon.2- Conjunctiva:- scarring, destruction of goblet cells &accessory lacrimal glands. - severe dryness. - symblepharon. - pseudo ptrygium.3- Cornea:- destruction of limbal stem cells chronic limbaldeficiency or failure. Ulceration, recurrent corneal erosions,opacification, vascularization thinning & perforation.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Complications4- Anterior chamber : turbidity & reaction.5- Iris : iritis, endophthalmitis, panophthalmitis in cornealperforations.6- Secondary glaucoma :Early: prostaglandin release , secondary to severe iritisshrinkage of collagen fibers of the sclera.Late: Occlusion of aqueous veins & anterior ciliary vessels byconjunctival fibrosis.Atrophia bulbi may follow severe cases.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    •  Representative photographs of patients with severe ocular surface burns (Grade 4 Roper Hall Classification and the equivalent Dua 4, 5, 6 ocular burn). The upper row shows the clinical pictures of the patients at presentation, and the lower row shows the corresponding slit-lamp photographs of the same patient at final follow-up visit: A–D: Grade 4 chemical burns (6–9 clock hours of limbal ischaemia); E–H: Grade 5 chemical burns (9–11 clock hours of limbal ischaemia); I–L: Grade 6 chemical burns (12 clock hours of limbal ischaemia); A, B, E, F, I, J: patients treated with standard medical therapy; C, D, G, H, K, L: patients who underwent amniotic membrane transplantation.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Laboratory Study The pH of the ocular surface should be periodically tested. Irrigation should be continued until the pH reaches neutrality. No other laboratory tests are generally necessary unless other systemic injuries are concurrentAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Medical Care Treatment of chemical injuries to the eye requires medical and surgical intervention, both acutely and in the long term, for maximal visual rehabilitation. Regardless of the underlying chemical involved, common goals of management include the following: (1) removing the offending agent, (2) promoting ocular surface healing, (3) controlling inflammation, (4) preventing infection, and (5) controlling IOP.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Immediate Management of Chemical BurnsAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Management of Ocular Chemical Injury 1)Remove inciting chemical (irrigation) Immediate copious irrigation of eye (every second counts) by sterile balanced buffered solution: •normal saline solution •Ringers lactated solution •Normal saline with bicarbonate •Balanced salt solution(BSS) However, immediate irrigation with even plain tap water is preferred without waiting for the ideal fluid. If available, the eye should be anesthetized prior to irrigation. Ideally,the eye should be irrigated with irrigation solution and must contact the ocular surface by: •special irrigating tubing (eg, Morgan lens) •lid speculum. Irrigation should be continued until the pH of the ocular surface is neutralized, usually requiring 1-2 liters of fluid.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Eye Irrigation2)Evert the upper eyelid and irrigate, and irrigate under lower lid. Remove all solid particles from under lids. After 5 to 10 minutes of irrigation and if litmus paper is available test pH of lower inside of lid. Continue irrigation until pH is below or above a pH of 7.0. If no litmus available irrigate for 20 minSpecial irrigating tubing(Morgan’s lens):Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Guidelines for first aid for chemical burns Water is contraindicated as a first aid  Speed in irrigation is also important as measure in chemical burns caused by the certain organic solvents are quickly absorbed heavy metals like sodium, potassium and calcium(e.g.Lime or Ca(OH)2). into the blood stream via the skin or by They react violently and explosively with inhalation and cause systemic toxicity. water to produce caustic hydroxide  Irrigation should continue even during the liberating much heat in its production and transport to the hospital. thus result in combination of thermal and chemical burn.  Never apply acid to base, or base to acid as it Immediate treatment in these cases is to can cause exothermic reaction generating- brush off/pick out from the skin as many heat resulting in further damage. particles of sodium or potassium as possible  Victims of mass casualty due to contact with and the hazardous materials (Hazmat) should be- then to direct a high pressure jet of water at the remainder. removed from the zone of immediate danger- Ignition of particles will occur, but if the and then decontaminated. Decontamination flow is great enough, the heat will be at a hospital is discouraged due to potential dissipated by water. spread of the substance to other patients. All Covering the remaining particles with oil, the areas utilised for decontaminating although prevents combustion, cannot halt victims must themselves be decontaminated the tissue damage as the remaining metal particles continue to react with tissue water. after use. Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    •  Instrument and kit used for eye irrigationAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Eye irrigationAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Transfer After completing initial irrigation and treatment, patients should be transferred to facilities that have ophthalmologists available to assume care for them.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Acute Management of Chemical BurnsAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Acute Management: after transfer to hospital It‟s better to place an eye speculum and topical anaethesia in the eye before irrigation. The lower lid is pulled down and the upper lid is everted to irrigate the fornices. Continue irrigation until pH reaches close to normal. Wash with available antidote if available:Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • If nature of chemical If nature of chemical is substance is known unknown or not available Strong Weak alkali acid Tap Dilute chemical Strong Weak acid water substance alkali *for all except LIME* Iodine Starch solution Milk Dilution Milk Buffer acid and alkali Aniline Alcohol 10% Form superficial film Glycerine 10% which protect the Lime a) Pick particles with underlying tissue forceps b) Wash by: EDTA 0.1% (universal antidote) Neutral ammonium tartarate 10% Saturated sugar solutionAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Promote ocular surface healing1- Remove inciting chemical• After instilling topical anesthesia, sweep the fornices with a moist sterile cotton swab to remove any retained foreign material.• This technique is especially important when particulate matter (eg, plaster) is responsible for the injury.2- Debridement Once irrigation has been initiated, an exhaustive search of the fornices is necessary to locate and remove sequestered particles of caustic material. If allowed to remain, these particles dissolve slowly, allowing additional toxic substances to leach into surrounding tissues. The search must include double eversion of the lids after application of 0.5% proparacaine solution and deep swabbing of the conjunctival recesses using moistened cotton-tipped applicators. Careful attention must be directed to those regions where extreme chemosis is likely to hide particulate matter in crypts and folds.3- Paracentesis The relative importance of irrigation is diminished slightly by findings that external perfusion of alkali-burned animal eyes, although vital in reducing surface pH, may be incapable of lowering aqueous pH by more than 1.5 units. A further decrease in pH by 1.5 units can be achieved by removing aqueous by paracentesis, using a 25- or 27-gauge needle inserted at the limbus under slit lamp visualization. If buffered phosphate solution is then used to refill the anterior chamber, a greater reduction in pH (another 1.5 units) is possible.4- Early Assessment During the first hour or two of emergency treatment with irrigation, debridement, and possibly paracentesis, critical evaluation of the severity of injury dictates the nature of further therapy.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Promote ocular surface(epithelial) healingPromote ocular surface (epithelial) healingOnce the inciting chemical has been completely removed,epithelial healing can begin by: Treatment Functions -Artificial tear supplement -as it cause poorly produce adequate tears. -Ascorbate -improvement in corneal healing. -Therapeutic bandage contact lens -until the epithelium has regenerated. -Amniotic membrane transplant in -promotes faster healing of eyes with acute ocular burns epithelial.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Med Term Management of Ocular Chemical BurnsAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Control inflammationInflammatory mediators released from the ocular surface at the time ofinjury causing:•tissue necrosis•attract further inflammatory reactantsThis robust inflammatory response causing:•inhibits reepithelialization•corneal ulceration•PerforationControlling inflammation will help to break this inflammatory cycleby using:Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Control infection and cicatrization-Topical antibiotic, aggressive lubrication with eye ointments (steroidantibiotic combinations) to prevent symblepharon.As the first week of treatment draws to a close, continued assessment of therisk of infection is essential.Persistent epithelial defects, necrotic corneal stroma, and corneal melting allfacilitate infection and therefore necessitate the continued use of topicalantibiotics.*Long-term use of topical antibiotics, however, can lead to development ofbacterial resistance or corneal toxicity from preservatives.*Prophylactic topical antibiotics are warranted during the initial treatmentstages.-Topical steroids should not be used if the corneal epithelium is intact.-Cyanoacrylate tissue adhesive may be applied for the treatment ofsmall corneal perforations to avoid infection.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Cyanoacrylate tissue adhesiveAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Control IOP (increase secondary to chemical injuries)Control IOP (increase secondary to chemical injuries) Oral acetozolamide(Diamox) or topical beta-blockers or aqueous suppressants is advocated to reduce IOP in severe exposure and both as an initial therapy and during the later recovery phase, if IOP is high (>30 mm Hg).Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Control PainControl pain Severe chemical burns can be extremely painful.• Cycloplegic agents for ciliary spasm• Oral pain medication initially to control pain.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Improves healing1- Steroids reduce inflammation and neutrophil infiltration. However, they also impairstromal healing by reducing collagen synthesis and inhibiting fibroblast migration. Forthis reason topical steroids may be used initially but must be tailed off after 7-10 dayswhen sterile corneal ulceration is most likely to occur. They may be replaced by topicalNSAIDs, which do not affect keratocyte function.2- Ascorbic acid reverses a localized tissue scorbutic state and improves wound healingby promoting the synthesis of mature collagen by corneal fibroblasts.Topical sodium ascorbate 10% is given 2 -hourly in addition to a systemic dose of 2 gq.i.d.3.3- Citric acid is a powerful inhibitor of neutrophil activity and reduces the intensity ofthe inflammatory response. Chelation of extracellular calcium by citrate also appears toinhibit collagenase.Topical sodium citrate 10% is given 2- hourly for about 10 days. The aim is to eliminatethe second wave of phagocytes, which normally occurs 7 days after the injury.4- Tetracyclines are collagenase inhibitors and also inhibit neutrophil activity andreduce ulceration.They are administered both topically and systemic-ally {e.g. doxycycline 100 mg b,d.}.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Delayed Management of Chemical Burn 1- CORRECTION OF LID DEFORMITY 2-CONJUNCTIVAL OR MUCOUS MEMBRANE GRAFT 3-AMNIOTIC MEMBRANE TRANSPLANTATION 4-LIMBAL STEM CELL TRANSPLANTATION 5-PENETRATING KERATOPLASTY 6-KERATOPROSTHESISAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Conjunctival ormucous membranegraft  Reconstruction of contracted fornices severalDivision of symblephara may be followed by amucosal graft from the upper conjunctival fornix of months after severe alkali burn. After lysis ofan unaffected fellow eye or from buccal mucosa. The symblephara, sheets of silicone rubber weregraft should be secured deep in the fornix bydouble-armed mattress sutures that first engage the sutured deep into the fornices. A scleral shellperiosteum of the orbital margin and then passthrough the lid to be tied over a square of 0.005- was inserted as a conformerinch silicone rubber sheet.An interim prosthesis,such as an acrylic shell or ring, must be used toseparate the lids from the globe, or symblephararapidly recurs. If there is bilateral injury or if it isnot possible to use a mucosal graft, larger sheets ofthe very flexible 0.005-inch silicone rubber can befashioned to line the exposed subconjunctival tissuein the deepened fornix . It is possible to use similarlya microthin polyvinyl plastic film of the type usedfor food wrap in the kitchen; this is easy to obtainand readily sterilizable with heat. These prostheticsheets must be sutured securely to the periosteum ofthe orbital margin, after which a scleral shell isinserted. Although conjunctiva grows over thesedissected surfaces, preservation of the deepenedfornices remains a major challenge becauseregrowth of symblephara is almost the rule. As thecicatricial bands form once again, retention of ascleral shell or silicone rubber sheets becomesincreasingly difficult. In an attempt to inhibitreformation of lysed symblephara, beta-irradiationhas been applied after excision of the scar tissue.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal. in correspondence to other student in group
    • Amniotic membrane Schematic diagram transplantation (above) showing double armed 4-0 silk fornix retaining sutures tied over bolsters, and 10-0 monofilament nylon sutures anchoring the amniotic membrane to the lid margins; (below) sagittal view showing amniotic membrane lining the entire ocular surface.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Amniotic membrane transplantation(AMT)Amniotic membrane is obtained under sterile conditions after elective caesareandelivery from a seronegative donor.1) AMT promoted healing of the ocular surface in all patients, as complete epithelialisation was achieved in all cases. It helps in corneal and conjunctival differentiation and regeneration.2) This action of amniotic membrane is by virtue of the epithelial basement membrane layer providing a mechanical support and acting as an internal splint.3) beneficial biological properties such as secretion of cytokines, growth factors and protease inhibitors which decrease surface inflammation and prevent fibrosis and symblepharon formation.4) AMT stabilises the ocular surface and provides a conducive surface for further procedures such as auto-limbal and allo-limbal transplantation, lamellar or penetrating keratoplasty.5) AMT can be considered as a useful surgical option in moderate chemical burns with non-healing epithelial defects. It may also be used judiciously in severe cases where close monitoring and follow-up are not possible, and compliance with medication is not satisfactoryAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Surgical procedure forconjuctival limbal autograft(CLAU). The conjunctivalizedpannus is removed from thecorneal surface by peritomyfollowed by superficialkeratectomy with bluntdissection in the recipient eye(A). The cicatrix was removedfrom the subconjunctival space(B). This invariably results inthe recession of the conjunctivaledge to 3 to 5 mm from thelimbus from the superior andinferior limbal regions (C). Twostrips of limbal conjunctival freegrafts, each spanning 6 to 7 mmlimbal arc length, are removedby superficial lamellarkeratectomy at 1 mm within thelimbus (D) and by including 5mm of adjacent conjunctiva.These two free grafts aretransferred and secured to therecipient eye at thecorresponding anatomic sites byinterrupted 10-0 nylon suturesto the limbus and 8-0 vicryl Limbal stem cell transplantationsutures to the sclera.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Limbal stem cell transplantation If no significant epithelialization has  To re-establish corneal taken place over a denuded cornea by epithelium over the exposed the third to sixth week after a severe stroma after a severe chemical chemical injury, eventual injury, it may be necessary to consider conjunctivalization with vascularization a limbal stem cell autograft or will probably occur unless the eye also homograft. has suffered profound loss of  A patient with a monocular conjunctiva. chemical burn is a candidate for The various characteristics of an autograft, but homologous conjunctival tissue, including its tissue must be used if both eyes vasculature and goblet cells, are slowly have sustained significant lost as the conjunctivalized cornea damage. undergoes transdifferentiation to a  The clarity, degree of adherence, and metabolically-imperfect corneal stability of the epithelial layer that epithelium. results from limbal stem cell Because of its instability and its transplantation cannot be matched tendency to vascularize after by any other current method of minor trauma, this new epithelial re-establishing tissue protection covering derived from conjunctiva is over denuded stroma. less desirable than true corneal epithelium.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Surgical procedure of keratolimbalallograft (KLAL). In the host eye thefibrovascular pannus is completelyremoved leaving in most of the limbalstem cell deficiency (LSCD) cases a clearresidual corneal stromal bed.One layer of amniotic membrane withbasal membrane up is place over thecornea as a graft and secure withinterrupted 8-0 vicryl to residualconjunctiva and scleral tissue around thelimbus. The donor central cornealbutton is removed by trephine and theresidual limbal ring is trimmed off and theunderlying stroma is thinned to create asmooth and thin corneal–scleral limbalring. The limbal tissue is then lay aroundcornea and secure with interrupted 10-0nylon suture. In order to promotecorneal epithelial healing another amnioticmembrane is placed over the cornea as apatch and secure to the scleral withrunning 10-0 nylon for 1 or 2 weeks (figurenot shown). If amniotic membrane isdissolved before 2 weeks, exposure and/orsevere inflammation should be suspectedand addressed.(Reprinted from Tsubota K, Satake Y,Kaido M, et al: Treatment of severe ocularsurface disorders with corneal epithelial Limbal stem cell transplantationstem-cell transplantation. N Engl J Med340:1697, 1999, with permission) Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Penetrating Keratoplasty Removing the Interrupted affected After removal of the corneal sutures corneal button corneal button. An (10/0 nylon) intraocular lens were used to measuring suture the donor 7mm in can be seen cornea to the diameter. centrally. recipients. Clear graft after penetrating keratoplasty utilizing and showing a continuous (running) 24-bite suture. (Courtesy of Alan Carlson, MD)Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Penetrating keratoplasty (PK)- Penetrating keratoplasty (PK) is one of the most common forms of tissuetransplantation currently performed. It can be an extremely successful procedure,with dramatic visual improvement for the patient.- can also be one of the most challenging and frustrating procedures for a patient to endure, with a prolonged convalescence, delayed visual improvement, and many postoperative challenges.- The technique of keratoplasty, or corneal grafting, involves removing the dysfunctional elements of the cornea and replacing those elements with healthy tissue. Full thickness keratoplasty is termed penetrating keratoplasty, and partial-thickness keratoplasty is termed lamellar keratoplasty.- the current number of procedures performed on an annual basis is decreasing slightly due to:* reflects improved cataract removal technique and technology, such asphacoemulsification and posterior chamber intraocular lens placement.* Many other complications can occur in the late postoperative period, some ofwhich are peculiar to corneal transplant surgery and others of which may be seenafter any intraocular surgery.* Chronic progressive nonspecific endothelial decompensation manifests as agradual onset of graft edema secondary to endothelial dysfunction not associatedwith prior rejection, uveitis, or glaucoma.*Recurrence of host disease inFaizal graft may be seen in several situations. Author& Disclosure:Dr.Afiqah Bt.Muhamed the in correspondence to other student in group
    • Cultures plus KeratoplastyAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • KeratoprosthesisAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Keratoprosthesis for corneal reconstruction after chemical injury has been largely unsatisfactory. The greatest limiting factor has been collagenolytic erosion of the interfaces at which corneal tissue adjoins prosthetic material Keratoprosthesis in chemical injury. Collagenolytic lysis occurs around the central optical post.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Keratoprosthesis in a grossly scarred corneaAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Summary of Suggested Action During the Late(Chronic) Period The tear film should be augmented when necessary with preservative-free artificial tears. Lysis of symblephara and reconstruction of the fornices, possibly with mucosal grafts, may be performed. Silicone rubber sheets and an acrylic conformer are useful. Correction of cicatricial entropion and trichiasis is necessary if keratoplasty is anticipated. Penetrating keratoplasty, with exquisite attention to the small details favoring success, may be performed.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Further inpatient careIn patients with severe chemical injuries, short hospitalizationmay be warranted to closely monitor:•IOP•corneal integrity•medication use•pain controlAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Inpatient & Outpatient Medications Prednisolone acetate 1% (1 gtt qid) Erythromycin ophthalmic ointment (4-8 times/d) Homatropine 5% or scopolamine 0.25% (1 gtt tid) Ascorbate (500 mg PO qid) Levobunolol hydrochloride 0.5% (1 gtt bid) or acetazolamide (500 mg PO bid) - Pressure lowering agents, such as levobunolol and acetazolamide, are only indicated if IOP is increased (>30 mm Hg).Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal incorrespondence to other student in group
    • Deterrence/Prevention  Education and training regarding the prevention of chemical exposures in the workplace can help prevent chemical injuries to the eye.  Persons who may be exposed to chemicals in the workplace are advised to wear safety goggles.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizalin correspondence to other student in group
    • Consultations In most instances, patients present to nonophthalmologists for their immediate care. At a minimum, patients with mild chemical injuries should have follow-up care arranged with an ophthalmologist. Any patient with a moderate-to-serious injury should be immediately evaluated and followed accordingly by an ophthalmologist. Other medical personnel may be needed as determined by the extent of the extraocular injuries sustained.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Prognosis In general, the prognosis of ocular • Grade 1 - Partial-complete epithelial chemical injuries is directly correlated defect, clear corneal stroma, no limbal with the severity of insult to the eye and ischemia adnexal structures. • Grade 2 - Partial-complete epithelial defect, mild stromal haze, none or only mild Many classification systems and limbal ischemia revisions thereof have been aimed at • Grade 3 - Complete epithelial classifying ocular burns in relation to defect, moderate stromal haze, less than one their prognosis, including the following third of the limbus is ischemic systems: Hughes, Roper-Hall, and • Grade 4 - Complete epithelial Pfister.[9] In essence, all systems aim defect, stromal haze blurring iris details, one third to two thirds of the limbus is ischemic to quantify the degree of corneal • Grade 5 - Complete epithelial epithelial involvement, the degree of defect, stromal opacification, greater than limbal stem cell loss, and the degree of two thirds of the limbus is ischemic conjunctival involvement.[16]  Grades 0-2 can be expected to heal well with Injuries can be graded from 0-5, as proper care and follow-up examinations. follows:  The course for grades 3-5 is more tenuous and may require surgical• Grade 0 - Minimal epithelial intervention, either limbal stem cell defect, clear corneal stroma, no limbal transplantation or penetrating ischemia keratoplasty, to regenerate the corneal surface.  Higher-grade injuries are more susceptibleAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group to secondary complications.
    • Evaluation Visual acuity Extensive history:  When the injury occurred  Chemical involved in exposure  Duration of exposure  Duration of irrigation  How long after exposure the chemical irrigation was begun.Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizalin correspondence to other student in group
    • Differential Diagnosis Differentials Diagnosis:• Conjunctivitis, Acute Hemorrhagic• Conjunctivitis, Allergic• Corneal Abrasion• Corneal Erosion, Recurrent• Corneal Foreign Body• Keratoconjunctivitis, Atopic• Keratoconjunctivitis, Epidemic• Keratoconjunctivitis, Sicca• Ulcer, CornealAuthor& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • References Ophthalmology for Undergraduate Medical Students (Tanta University textbook) Kanski Clinical Ophthalmology Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizal in correspondence to other student in group
    • Author& Disclosure:Dr.Afiqah Bt.Muhamed Faizalin correspondence to other student in group
    • FINISHAuthor& Disclosure:Dr.Afiqah Bt.MuhamedFaizal in correspondence to other student in group