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ARTICLE |
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Year : 1968 | Volume
: 16
| Issue : 4 | Page : 228-231 |
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Chemical burns of the conjunctiva and cornea
BT Maskati, SD Adrianwala
Ophthalmic Dept. King Edward VII Memorial Hospital, Parel, Bombay, India
Date of Web Publication | 24-Dec-2007 |
Correspondence Address: B T Maskati Ophthalmic Dept. King Edward VII Memorial Hospital, Parel, Bombay India
Source of Support: None, Conflict of Interest: None | Check |
How to cite this article: Maskati B T, Adrianwala S D. Chemical burns of the conjunctiva and cornea. Indian J Ophthalmol 1968;16:228-31 |
Injuries due to chemicals are some of the most treacherous injuries of the eyes. Whereas the natural protective mechanism offered by the peculiar bony anatomy of the orbit offers protection against injuries caused by larger sized lethal objects, and the brisk movement of the lids and a quick secretion of tears against smaller sized ones, the fluid nature of most of the chemicals that get splashed on to the eyes and face know no anatomical or physiological bounds. They cause chemical burns not only of the eyes but of the protective mechanisms themselves and sometimes end in the most ugly and debilitating scarring of the face, lids and conjunctiva which tax the ingenuity of a plastic surgeon later. The ultimate damage is greater than the immediate reaction may suggest. It will depend on a) concentration of chemical b) duration of contact is ocular bisues c) chemical reaction which can take place c the bissue components and d) diffusibility of the agents.
Of the two, alkaline burns are more vicious, for if not washed away early, mild at first the), enter the stroma to set up an inflammatory process which penetrates deeper and progresses from day to day as we look helplessly on. Chemicals are used often to settle private scores and eke vengeance out of frustration. Fortunately for these homicidal attempts, almost always, acids are chosen.
Secondly such wounds easily get infected, adding to the product of destruction, so that in all chemical burns it is not possible to predict the eventual outcome, the end result. That is why they are treacherous.
Great progress has been made since the last war in the treatment of chemical burns and although the eventual results may be better, chemical burns of the eyes and face need more than the usual respect and attention, that thermal burns and injuries of the eyes from other causes, receive.
Materials and methods | | |
This paper is an analysis of cases of chemical burns treated as inpatients in the K.E.M. Hospital, Bombay during the last five years. Special emphasis has been laid on the management of these cases.
Thirty seven cases of corneal burns were admitted to the ophthalmic ward of the K.E.M. Hospital, during the last five years. The cases have been analysed according to
1) Nature of injury, viz. which chemical was responsible
2) Intention of injury, viz. suicidal, homicidal or accidental
3) Age and Sex
4) Unilateral or Bilateral
5) Modes of Treatment (First-aid, local and systemic)
(1) Nature of Injury:
1) Acid burns - 11 cases
2) Alkaline burns - 23, cases. Of these, 13 were clue to lime, 6 due to caustic soda, 3 due to ammonia and one due to an adhesive paste.
3) Miscellaneous 3 cases. Of these one was due to silica, one due to potasium permanganate, and one due to lysol (the patient was a doctor).
(2) Intention of Injury: The majority of these cases, (33) were accidental, three were homicidal (all acid in nature) and one was suicidal (also acid in nature).
(3) Age and Sex: Only three cases out of 37 were below the age of 12 years (8.1%). The remaining 34 cases were above the age of 12 years (91.9%).
Only five cases were females (13.5%). The remaining 32 cases were males (86.5%). The sex distribution is rather overwhelmingly male, because in this series accidental cases predominated, where the majority of workers were male.
(4) Whether unilateral or bilaeral: In 18 cases, both eyes were involved, whereas in 19 cases only one eye was involved.
Treatment | | |
Treatment can be divided into first-aid, local and systemic.
First-Aid: This forms an essential part of the treatment. Chemicals, since they set up a progressive reaction of destruction when in contact with the tissues, must be removed as soon as possible. This can be done by removing all pieces of garment soaked in the chemical and washing the eyes and face with copious quantities of water to dilute the chemical if not actually to wash it away. A proper first aid of this nature can make all the difference between a good and a bad end result. However, in the case of lime burns, it is important not to apply any water, otherwise slaked lime that is produced on mixing with water adds to the destruction from the intense heat liberated. It is best to pick out the lime pieces, preferably under intravenous anesthesia as soon as possible. Lime can also be washed away by a continuous stream of cold water on boric lotion as the cold wash will neutralise the effect of liberated heat. The stream, however, must be continuous, and continued for 15 to 20 minutes. The use of EDTA (ethylenediaminetetra acetate) has been recommended in cases of lime burns to prevent the formation of slaked lime. Moreover the lime particles become less adherent after the use of EDTA.
Local treatment can be further subdivided into medical and surgical.
Medical treatment locally includes the use of 1% atropine drops twice a day, corticosteriod drops two hourly round the clock (preferably betamethasone or dexamethasone). CORVASYMTON (p-Methylamino ethanolphenol-tartrate) or oxedrine tartrate drops two hourly have proved very useful. The last named drug is actually an analeptic or a cardiac stimulant, but it was accidentally discovered to be useful in alkaline burns of the cornea. It prevents the delayed penetrating damage caused by the alkali. Locally any antibiotic may be used to prevent infection.
Surgical treatment of chemical burns:
Particles of Lime should be removed from the fornices with a pair of forceps, prior to washing the eye, so that no dissolution of the lime particles occurs. If necessary a double eversion of the lid may be done to remove particles from the upper fornix.
In cases of severe conjunctivocorneal burns where one expects symblepharon formation, it is most essential to keep the palpebral and bulbar conjunctiva apart. This can be clone either by passing a glass rod in the fornices twice a day or better still by leaving an inert tissue between the two. Sorsby recommends an amniotic membrane and he describes a method of preparing and preserving amniotic membrane to be available for immediate application. It mixes with the conjunctiva and needs no removal. A fresh piece of amniotic membrane can also be used for the purpose, but it should be removed aseptically and kept in a penicillin solution for an hour before use. Before use all fatty matter should be removed gently with a piece of gauze clipped in a 2% caustic potash solution. A piece 5 cm x 5 cm should be sufficient and stitched from fornix to fornix without stretching. A window is cut over the healthy cornea to promote corneal respiration.
An egg membrane can also be used for the same purpose. In our series, egg-membrane grafting was done in 4 cases.
A hard boiled egg is peeled with aseptic precautions and the membrane over the egg is then slit and peeled off. A square of this membrane is sutured to the conjunctiva both superiorly and inferiorly, nasally and temporally. A small window is cut open in the membrane over the cornea to promote corneal oxygenation. The membrane prevents adhesions between the palpebral and bulbar conjunctiva.
Superficial keratectomy was performed in two cases, one of severe acid burns and one case of lime burns. This was done to remove and debride the cornea of the superficial eschar, so that corneal healing would be promoted. Therapeutic lamellar grafting can also be clone instead of simple keratectomy.
Horwitz strongly advocates surgical debridement daily of the necrotic conjunctival tissues, plus superfical debridement of necrotic corneal tissue, for the first five to seven clays. In his opinion, this helps the return of visual acuity to normal.
Systemic Treatment:
The use of systemic antibiotics, preferably broad-spectrum, helps to prevent secondary infection.
Systemic corticosteroids, ACTH and other anti inflammatory agents of the butazolidine group (e.g. oxyphenylbutozone or Tanderil) help in minimizing the inflammatory reaction.
In obviously malnourished patients, vitamin C and high proteins in the diet promote healing.
In cases where permanent corneal damage remains, keratoplasty (either lamellar or penetrating as required) may be clone to improve visual acuity.
Prognosis | | |
It depends on the degree of conjunctical and corneal necrosis that has taken place by the time treatment is commenced, the rapidity with which treatment can be instituted, the degree of secondary infection and the general condition of the patient.
Results | | |
Visual improvement following chemical injuries depends on the Severity of the burns of the cornea, interval between injury and treatment and the nature of the irritant.
In our series, we have found that acid burns on the whole have a comparatively better prognosis than alkaline burns. Of the alkaline series, lime burps have the worst prognosis while all cases of ammonio burns recovered completely.
Summary | | |
Thirty seven cases of chemical injuries of the eye have been analysed as regards nature of injury, type of injury age and sex incidence.
Special discussion about treatment has been elaborated.[2]
References | | |
1. | Horwitz, I: Management of Alkali Burns of the Cornea Amer. J. Ophth. 61, 340-1 (1966). |
2. | Sorshy, A: Chapter 44 "Amniotic Membrane Crafts in Burns" in Sorsby's Modern Trends in Ophthalmology. Vol. II. p. 503 Butterworth, London (1948). |
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