|Year : 1961 | Volume
| Issue : 3 | Page : 43-50
M.G.M. Medical College and M.Y. Hospital, Indore, India
|Date of Web Publication||7-Apr-2008|
R P Dhanda
M.G.M. Medical College and M.Y. Hospital, Indore
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Dhanda R P. Keratoplasty-recent experiences. Indian J Ophthalmol 1961;9:43-50
One of every 200 people is presumably blind in this country, and it will probably be agreed that excluding cataracts, corneal diseases should account for more than half the incidence of blindness and this therefore is and has always been a national problem.
Corneal grafting had been conceived as a possibility long before the first successful grafting was reported by Zirm (1906). Reisinger (1824), Marcus (1841), Powers (1872), Von Hippel (1877), Fuchs (1894) were among those whose trials and newer conceptions kept corneal surgery as a live possibility through those days when surgery had not yet stood on its own legs. It 'was Elschning (1908) who first started keratoplasty and Filatov (1913) soon joined him and both laid the solid foundation to the present successes. But the credit of taking keratoplasty out of experimental stages goes to Castroviejo who among the living corneal surgeons is still improving upon techniques from time to time ever since 1931, so that corneal surgery now carries with it more success than failures. Attempts at scientific and regular corneal surgery in India have unfortunately been too few in midst of this vast sea of blindness. Modi (1958) reported o cases of penetrating keratoplasty but with unexplainable passiveness. Practice of acrobatics in eye surgery like the grafting without stitches with unseen failures not only provides an amusing material but would in the long run dishearten even the optimists and the brave. Corneal surgery needs a positive approach and not an ostrich policy. If "taking of the graft" is the only criterion, successes of grafting will be more than 100% What has been probably lacking in such approach is the want of basic concepts and I would therefore first of all emphasise on some of these.
Nutrition of the cornea is mainly by diffusion from the Timbal vessels through lymphatics and getting into the corneal tissue through interlamellar spaces. If this is true, functional and nutritional viability of the surrounding tissue in which a graft is placed is highly important for maintaining the transparency of the graft. That is why a donor graft should be surrounded by a healthy transparent cornea at least along more than half its circumference if the graft is to receive adequate nourishment and remain healthy and transparent. If on the other hand a graft is placed in a ring of densely opaque and nutritiously dead cornea with scarring having blocked the channels of nutrition, the graft surrounded by such cornea may too become opaque and die of starvation. This further explains the importance of direct cornea to cornea stitching of the graft because microscopic disturbance between the edges of the recipient and donor cornea would not permit formation of adequate nutrition channels and would therefore jeopardise the transparency of the graft.
Another important fact to appreciate is that the single cell posterior endothelial layer of the cornea is the most vital layer for the viability of the corneal tissue. Although not clearly understood, the endothelium of the cornea is the first tissue to die after extinction of life and that explains that graft from an eye removed more than 6-8 hours after death or stored more than 4-6 days even far below the ice temperature develops an endothelial oedema and is not likely to remain clear if grafted to a recipient. It also explains the larger incidence of successes in lamellar keratoplasty where endothelium does not form a part of the donor material in contrast with the penetrating keratoplasty where the whole thickness of the corneal tissue including the endothelium is grafted as donor material.
| Donor Material|| |
The present position continues that only a fresh donor material can be successfully used for penetrating keratoplasty. But the outlook to lamellar keratoplasty has definitely improved with the successes in the methods of preservation of the eyes and corneas even for 18 months to 2 years after removal.
At present there are three established methods of preservations of donor materials.
1. Deep freeze refrigeration of the eye ball as a whole at-79° C temperature which can only be created in a block of Carbondioxide snow, a method being practised at the Banting Institute at Toronto.
2. Lyo-philisation and dehydration of cornea in vaccum as practised in Lyons by Paufique.
3. Corneas with a rim of sclera preserved in glycerine under conditions of perfect vaccum are being supplied from the Ocular Research Unit at Washington Hospital Centre.
The only source at present of the donor material in this country is from the unclaimed bodies. While visiting the corneal surgeons in U.S.A. and Canada last year, the one question asked by everyone was, "How will you get donor material in a country like India because of the deep religious prejudices of Indians". I am however much more luckily placed because in the first nine months of the Regional Eye-Bank at Indore, as many as 73 eyes became available as donor material. I owe it to the active co-operation of the other departments, my 22 years association with the institution and the ceaseless efforts of my colleagues. I think it should be possible everywhere.
This source of donor material is however going to dwindle with economic progress, deminishing illiteracy and the growing legal psychology of the public. It is imperative therefore that with distant future in mind a campaign for donation of eyes should be sponsored through publicity and through the non-official agencies like the Red Cross, the Lion's club and other social organisations.
| Indications of Keratoplasty|| |
To a corneal surgeon in the West, the commonest indications for keratoplasty are :
1. Conical cornea.
2. Corneal dystrophy.
3. Interstitial keratitis.
4. Therapeutic indication like Herpetic keratitis.
But to us the problem is radically different. If an Indian Ophthalmologist looks through the eyes of his counterpart in the West no wonder a common statement is made that in India one hardly comes across a suitable recipient. True if we adopt and not adapt. Our problem is Trachoma, its sequelae and complications resulting in ulcers and opacities which not infrequently cover the whole cornea, quite often have perforated and are accompanied by anterior synechia. These have always been the bugbear to any prospective entrant in the realm of keratoplasty while the experienced ones have taken shelter under this pretext. Trachoma and anterior synechia are certainly matters for consideration but not contraindication and one of the major purposes of this talk is to convince you that the approach in our circumstances has to be conditioned to this altered etiology and pathology.
Out of the first 122 cases referred to this unit for suitability of corneal surgery, 60 (50%) had Trachoma. Again out of another 50 cases of corneal opacity considered suitable for keratoplasty in an Eye-Camp 34 (68%) had Trachoma. So that from whichever angle you approach the problem, you cannot escape this bugbear.
The problem of anterior synechia, the leucoma adherens, is again something which we cannot bypass if corneal surgery is to contribute towards alleviation of blindness in this country. In the series of 40 cases on which keratoplasty was actually performed, 17 had an anterior synechia, of some size varying from a small tag to extensive adhesions and 19 had established Trachoma including 4 with complications.
| Choice of Surgery|| |
Having to start corneal surgery in 1960 and specially after a visit to most of the important corneal surgeons in United States and Canada, with encouragement in the matter of bate surgical necessities and an. enthusiastic colleague, we adopted the technique of present day surgery of direct cornea to cornea stitching. Of the 52 cases of corneal operations we have performed, 29 penetrating keratoplasties varying from 6.5-9 mm. in size and 14 lameilars from 7-11 mm. in diameter, and 8 keratectomies. The suturing material used was 7-0 silk and depending upon the size of the graft we applied from 14--22 interrupted stitches in cases of penetrating and 12-16 in cases of lamellars. The whole purpose of direct stitching in present day corneal surgery and probably the only sound way to successful keratoplasty is to make the anterior chamber a tight compartment. In spite of this close stitching it was not always easy to inject and retain enough air in anterior chamber. In three cases penetrating keratoplasty was done twice on. the same eye and of these two did very well indeed. In one case I faced an interesting situation. When doing a keratectomy with no donor eye at hand, the cornea was inadvertantly perforated. A penetrating keratoplasty with preserved cornea I had brought from Washington, was completed. Even though this preserved cornea showed definite signs of clearance at first dressing, the graft was replaced by a fresh one 24 hours after the first surgery and this case did very well indeed.
Of the 14 lamellars, three were preparatory to penetrating surgery, three were therapeutic lamellar for trachomatous panes and the other eight being the regular lamellars. Eight pro-operative and two post-operative peritomies were done in cases of marked vascularisation of the cornea either before or at the time of surgery.
The following table is a summary of the results of the first 47 cases of corneal surgery.
Our best visual result in penetrating was with correction, 6/9p 6/6p in a girl aged 11 years and in lamellar 6/24 in a case of complicated Trachoma
Although it is suggested that keratoplasty should not be undertaken under the age of 14 years (Paton), we have operated on nine children below this age, the youngest being a girl of 4 years, and among our best results are in these.
| Post-Operative Complications|| |
During this early phase of our corneal surgery life we have faced complications as every corneal surgeon would even after long experiences. The uncertain elements in this surgery might dampen the enthusiasm but should not lead to dejection. Unlike our counter parts in West our cases were not and could not be ideal from their point of view.
1. Anterior synechia and iris prolapse. With the direct con neo-corneal stitching one mm. apart, chances of iris prolapse are very few. We had to excise iris knobs in two cases in the early stages but with improvements in stitching technique we did not face this complication any longer. However isolated anterior synechia with the posterior corneo-corneal groove are more frequent in cases where keratoplasty was performed in leucoma with extensive anterior s7nechias and this was responsible for loss of one eye due to secondary glaucoma and resulted in opacification of graft in another three cases.
2. Falling off of stitches. Too small a bite of corneal tissue while stitching and restlessness on the part of the patient would be responsible for this and in our early series there were cases when between the 14th to 21st day after surgery there were hardly any stitches to be removed. Since we have started keeping both eyes bandaged for one week after surgery we have a pleasent experience that most of the stitches are in place even up to the 21st day and they are removed any time during the week after this. Slight displacement of the graft forward due to early falling out of stitches in 3 cases could be controlled by tight pressure bandage.
3. Vascularisation of graft. In view of the extensive association of Trachoma with corneal disease in this country, it is surprising how few of our grafts were invaded by neo-vascularisation. Most of the blood vessels come up to the graft margin and stop short at that. However in a case of chemical burns due to ammonia, the vascularisation of the graft was so extensive as to result in complete opacification. It is reported that a case of ammonia burn is yet to have a successful keratoplasty.
4. Ulceration. Superficial epithelial ulceration of the graft was faced in four cases, two penetrating and two lamellar. The ulcers are extremely resistant to treatment probably because the sensory nerve supply of the graft does not regenerate for months after surgery or due to some trophic tissue changes. Ulceration was responsible for opacification of grafts in all the four cases and in one case of lamellar keratoplasty even a re-grafting was followed by ulceration and opacification.
5. Oedema and opacification. Uncertainties of the yet unrecognised immunological reactions even in cases of grafts placed under most suitable circumstances and ideal surgery done is as much a problem in the West as it will be in the East. A co-ordinated and active basic research work more so in a country like India where problem of corneal disease is made so different by Trachoma could alone provide some answer. A three hourly instillation of hydrocorti sone drops and if necessary a systemic administration helped us overcome this complication quite often. We were prepared to use hydrocortisone any time after the seventh post-operative day.
6. Subluxation of Lens. One thing which at times makes the surgeon and the assistant perspire is when the button from the recipient eye has been removed and large tags of iris remains from leucoma adherens have to be excised, the lens starts moving forward through this wide gap. One can only attempt to slow its passage forwards till one is able to put in four vital quadrant stitches. The partially dislocated lens has to be removed better extracapsularly than intracapsularly. We faced this situation in 5 cases of leucoma with extensive adhesions, and only in one of these cases, the graft remained clear. In another two the graft was clear for about a month and then started becoming hazy.
The paper was followed by a movie showing the surgical technique used.
| Summary|| |
Difficulties in securing donors and suitable recepient eyes in India are emphasised.
Results of 25 cases of penetrating keratoplasty, 13 cases of lamillar keraplasty and 9 cases of keratectomy are tabulated and discussed.
The complications are described and the means adopted to minimise the same are stated.
[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4], [Figure - 5], [Figure - 6], [Figure - 7], [Figure - 8], [Figure - 9]
[Table - 1]