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ARTICLES |
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Year : 1982 | Volume
: 30
| Issue : 4 | Page : 213-218 |
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Ophthalmic use of topical corticosteroids
SK Angra
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, A.I.I. M.S. New Delhi, India
Correspondence Address: S K Angra Dr. Rajendra Prasad Centre for Ophthalmic Sciences, A.I.I.M.S. New Delhi-110029 India
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 7166392 
How to cite this article: Angra S K. Ophthalmic use of topical corticosteroids. Indian J Ophthalmol 1982;30:213-8 |
The local use of corticosteroids are gaining more and more usage on judicious and empirical grounds. Their hazarduos disadvantages like enhancement of infections, steroids induced ocular hypertension and delayed healing, cannot be over looked. In considering the Ophthalmic use of local corticosteroids therapy, We are to ponder over the following points.
1. Can we be unconventional in using corticosteroids in infective corneal conditions?
II. Do diluted steroids really effectively control inflammations?
III. Is ocular hypertensive effect of corticosteroids a contraindication in their use in post-operative glaucoma surgery?
IV. Is use of corticosteroids beneficial in cataract surgery?
Thus keeping in view the clinical and pharmacological goals of therapy (optimal effects, decimal hazards and minimum dose) and hazards of corticosteroids, we have attempted to probe into the topical corticosteroids administration in ophthalmic therapeutics.
I Can we be unconventional in using corticosteroids in infective corneal conditions?
In order to gauge with maximum possible precision the efficacy of a drug and its possible toxicity an excellent experimental model is imperative. In that attempt we have evolved an in vivo corneal system of multiple microinoculations of chemicals and infectious agents on a single cornea[1],[2][Figure - 1]
Experimenting on our experimental model we have observed that Dexamethasone in 1:10 or 1:20 dilutions have no virus or fungal replication enhancing effects even when used 10 times a day. While 1:5 diluted or full strength of Dexamethasone enhance replication of virus and fungus. Also, that the full strength of corticosteroid drops has more pronounced effects than 1:5 diluted corticosteroid (Dexamethasone) drops. It has also been found that diluted corticosteroids have no danger of enhancing the collagenase effects produced after alkali injuries of cornea. This concept we have utilised in treating clinical cases of herpes keratitis and fungal keratitis requiring use of corticosteroids[3],[4].
We used either of the following criterion for the use of diluted (10 times or more) corticosteroid drops:
(i) Extensive inflammatory reaction in cornea and uveitis non-responsive to specific therapy threatening disorganisation of inner structures of eye.
(ii) Evidence of immunological reaction like immune ring etc.
(iii) Where therapeutic keratoplasty is required. This will reduce the preoperative inflammation and corneal grafting is much more successful.
Using 1:10 diluted dexamethasone (0.1%) drops in combination with I.D.U. 6 times a day in stromal and disciform keratitis. We could achieve good therapeutic response without any recurrence of reactivation of herpes epithelial keratitis in diluted corticosteroid groups whereas the reported reactivation rate is 42% using full strength of steroids alone and 15% when used in combination with 1.D.U.[5] The recurrences following the withdrawal of the therapy have been reduced to 13.3% from 79% reported by Aronson & Mooref [Table - 1]
The failures of antifungal therapy of Fungal keratitis are to the tune of 38% in our series. But 68.75% of such eyes were savad by supplementing the therapy with 1:10 diluted costricosteroid drops [Table - 2].
This therapy of diluted corticosteroids is to be combined with effective specific antiviral or antifungal agent though experimentally it was proved that 1:10 or 1:20 dilution of corticosteroid drops do not enhance the injurious effects of virus or fungus. This should be continued for 2 weeks after a clinical cure. There should be graded reduction in frequency and strength (1:20, 1:50, 1:100) of the corticosteroid, over a period of time, to avoid recurrences due to ti,sue-corticosteroid addiction.
II. Do diluted steroids drops really efficientlycontrol inflammation?
We have evaluated the anti-inflammatory action of local corticosteroids in matched cases of anterior uveitis and found there is no statistical difference between beneficial responses between full dose corticosteroids and 1:10 or 1:20 diluted corticosteroids [Table - 3], when frequency of their application is altered.
Our observations are in conformity with those of Brown[7] that diluted corticosteroids have anti-inflammatory effect in strengths of 0.01, 0.005%. To achieve adequate response we have to increase the frequency of usage of diluted corticosteroids depending on the severity of the reaction. The advantages of diluted corticosteroids are non-promotion of organismal growth, non-interference in healing processes and having adequate therapeutic effects.
III. Is ocular hypertensive effect of local corticosteroids contraindication in their use in post-operative glaucoma surgery?
In glaucoma surgery, surgical trauma causes inflammation which demand the use of corticosteroids to save functioning of angle structures from inflammatory response as well as its debris. Their ocular hypertension inducing effects prohibit their usage. We have selected 5 gg responders to full strength dexamethasone and were put on coded drops in both eyes; one eye receiving 1:10 diluted dexamethasone and the other 1:20 diluted dexamethasone 4 times a day for 4 weeks.
Our observation [Table - 4] is in conformity with Armaly[8] and is at variance with Podos and Becker[9]. The variability of corticosteroid induced ocular hypertension not only relates to individual's response but to its concentration, frequency and duration of usage as well as the nature of the compound. The new agents like Mydrysone (1%) and tetrahydrotriamcinolone has no such eflects.
Thus it can be concluded that the use of 1:10 or 1: 20 dexamethasone (0.1 %) for specified periods, is safe to be used in glaucoma patients after intraocular surgery or when there is an associated uveitis as there is no risk of pro clueing ocular hypertension.
IV. Is use of corticosteroids beneficial in cataract surgery?
The local use of corticosteroids in postoperative inflammations remains controversial.
Such usage can not be avoided at times inspite of potential hazards. Burde and Waltmanlo found increased incidence of filtering blebs and iris prolapse attributed to poor wound healing with the use of 0.1% Decadron drops while Mustakallio and associates" found no increased complications attributed to the use of topical steroids. While Corboy[12] found it beneficial in reducing ocular inflammation in post-operative period.
We endeavoured to probe into the effect of local corticosteroid drops in checking the postoperative inflammations, avoiding hazards of delayed wound healing and promotion of infections.
(a) Evaluation of corticosteroids in checking the injurious effects of operative trauma
The evaluation of sub-conjunctival injections of 0.25 mg and 1 mg dexamethasone at the end of cataract surgery at the operation table was done, by comparing results with those without sub-conjunctival injections, in terms of congestion, striate keratitis, iritis and conjunctival discharge. These signs were scored and compared after 24 hours of surgery [Figure - 2].
It was noted that use of subconjunctival injection of corticosteroids supplemented with an antibiotic, at the table had reduced the deleterious effect of operative trauma to its low ebb. It was also observed that there was no statistically significant difference between, the beneficial effects of 0.25 mg. and 1.0 mg dexamethasone sub-conjunctival injection at the operation table. Thus only 0.25 mg Dexamethasone is recommended at the operatior table in cataract surgery as this minimum dose avoids steroid hazards too.
(b) The appraisal of use of corticosteroidh in cataract post-operative period?
This was done by randomising and dispens .sub ing masked drops of placebo, 1:10 dexamethasone and full strength of dexamethasone to 20 patients of each group having intracapsular lens extraction done. Their signs were scored in terms of congestion, striate keratitis, iritis [Figure - 3].
It was observed that 1.10 diluted dexamethasone is having beneficial effects equivalent to that of full strength of dexamethasone in controlling post-operative inflammations as compared to placebo. It took longer time for astigmatism to settle in cases using full strength of dexamethasone as compared to those using diluted dexamethasone and placebo drugs [Figure - 4]. It indicates that the consolidation of the operative scar is delayed with full dose of corticosteroids. It was observed that 1:10 diluted dexamethasone is having no evidence of delayed healing or bleb formations which is seen with the use of full strength of dexamethasone.
Thus we conclude
1. Our studies establish a dose-frequencyresponse concept of topical corticosteroids in ophthalmic therapeutics.
2. It is recommended to establish a ``minimum dose-frequency optimal response without hazards"-concept in various ophthalmic disorders.
3. The "indicated" use of diluted corticosteroids should not be refrained in ophthalmic therapeutics.
References | |  |
1. | Angra S.K., 1976, East Arch., Ophthalmol, 2: 239. |
2. | Angra S.K., 1976, Acta 6th Afro-Asian Congress of Ophthal. at Madras p. 239. |
3. | Mukherjee, G, Mohan M & Angra S.K., 1979, East Arch Ophth. 7 : 34. |
4. | Angra, S.K., Mohan M and Mukherjee, G, 1980. Proc. All India. Ophth. Soc. Manipal. |
5. | Jones, B.R., 1967 T.O.S.U.K., 87: 59. |
6. | Aronson, B.S. & Moore, T.E., 1969, Amer. J. Ophthalmol. 67 : 874. |
7. | Brown, D.C., 1979, Symposium on ocular antiinflammatory Therapy, Springfield ill. Charies C. Thomas. |
8. | Armally. M.F., 1967, Steroid & Glaucoma, in Symposium no Glaucoma Trans. new orlean acad, Ophthalmol. St. Louis C.V. Mosby Co. |
9. | Podos, M.S. and Beeher, B, 1972, Symposium of ocular Therapy ED. 1. Leopold, C.V. Mosby P. 90. |
10. | Burde, R.M. and Waltman, S.R., 1972, Amer. Ophthalmol. 4 ; 290. |
11. | Mustakallio, A., Kaufman, H.E. and Johnson, G., Wilson, B.S. Robert M.D. and Harter, J.C, 1973, Amer. J. Ophthalmol. 6 : 719. |
12. | Corboy, J.N., 1976, Amer. J. Ophthalmol, 82 : 923. |
[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4]
[Table - 1], [Table - 2], [Table - 3], [Table - 4]
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