PENETRATING KERATOPLASTY : INDICATION , OUTCOMES , AND COMPLICATION

1. Third year resident doctor, department of ophthalmology, ssg hospital Vadodara. 2. Senior resident doctor, department of ophthalmology,ssg hospital Vadodara. 3. Associate professor department of ophthalmology, ssg hospital Vadodara. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History


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transplantation is attributed to eye bank storage technique, ocular pharmacology, equipment and modern surgical technique 2 .
This fact has inspired this modest attempt to study the factors responsible for the failure of this sight restoring and integrity preserving surgery in our impoverished conditions.

Materiales and Methods:-
This prospective study will include 50 penetrating keratoplasties performed during a period from Sept.2015 to Aug.2016 at S. S. G. Hospital, Vadodara after taking all inclusion and exclusion criteria's in consideration .
Inclusion criteria:-1)All the patients with visual acuity of minimum, light perception and projection of light rays in all quadrants.2)All cases with non healing corneal ulcers, recurrent corneal ulceration, perforated corneal ulcer and corneal ulcers not responding to any medical line of treatment were taken for therapeutic penetrating keratoplasty.3)All cases of leucomatous corneal opacities following any reason like trauma, ulcer, and chemical burns etc. but having at least good perception and projection of light and posterior segment anomaly ruled out on USG B-Scan.4)All case of corneal dystrophies and degeneration.5)All cases of keratoconus and ectasias. After taking written and informed consent about enrollment in the study and maintaining adequate privacy and confidentiality, all patients were undergoes all the standard pre-operative examination for keratoplasty surgery. Donor corneas were inspected and then trephined. Trephination of recipient corneas will be undertaken and donor corneas was sutured to recipient using 10/0 Ethicon sutures. Patients were discharged after 8-10 days and regular follow up of the patients were maintained as weekly for one month and around every 15 days for next two months. Local instillation of antibiotic and steroids where indicated will be continued with regular check-up of IOP during follow ups.During follow ups post-operative vision, tension, with slit lamp examination for graft clarity, epithelial defect, vascularization, ectasia, suture position and wound leakage, anterior chamber depth, any iris graft synechia were examined.

Results:-
Demography:-Out of the 50 cases studied, 34 cases were male patients [68%] and 16 cases were female patients [32%].Maximum incidence of cases were in the age group of >60 year both in males and females.     Conjunctival peritomy was done in 48% of the Optical and 20% of therapeutic cases.

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In 88% of the Optical Cases the graft size was 7.5 mm or 8.0 mm (Theoretically the best size graft). 72 % of the therapeutic grafts were larger than 8.0 mm in an attempt to cover the host pathology in Therapeutic cases. In all cases the recipient bed prepared was 0.5 mm smaller than the donor graft. Vitreous disturbance during surgery were found in total 08% cases of penetrating keratoplasty.
Peripheral button hole Iridectomy was done in 60% cases of OKP while in 20% cases of TKP all the cases. AC Reformation is done by Air in 90% cases.

Discussion:-Factors Influencing The Survival Of Graft:-
In our study, the incidence of unfavorable prognostic factors such as vascularization , history of previous cataract surgery and associated systemic disease like DM and HT was high. Wiggin's et-al noted that as high as 69% of the patients with such unfavorable factors had graft failure.
In our study majority of the donors were above 40 years. The average age of the donor eyeball was 65 years and the incidence of Primary endothelial failure was 20% overall; whereas in study conducted by Wiggins et al, the average age of the donor eyeballs was 41 years and the incidence of primary endothelial failure was 0%.Thus, age of the donor eyeball appears to be a major factor in deciding endothelial function. Rejection  09  08  Primary Endothelial Failure  04  06  Complications after Surgery  12  11 302

OPTICAL THERAPEUTIC
Post Operative Complications:-The incidence of infectious in our study was 20%; same in the therapeutic [20%] than on optical [20%]. The severity varied from stitch infiltrate to frank corneal ulceration and infection was a direct cause or a contributory factor for failure. In contrast, Tuberville et al reported a 4.9% incidence of infective keratitis after PKP and attributed it to the use of corticosteroids, loose sutures, bandage contact lenses or antecedent herpetic keratitis. The post-operative infections can be a continuation of preoperative microbial keratitis. The incidence of uveitis in our study was 14%[ 16 % in optical and 12 % in therapeutic].The strong correlation between intraocular inflammation[without any allograft rejection reaction] and graft opacification has been emphasized by Polack FM and he as thought of endothelial failure induced by uveitis as a cause of failure.
Our study showed vascularization in up to 40% in optical and up to 48 % in therapeutic cases, and incidence of rejection was 36% and 32 % respectively.
Paque J and Poirer R noted that neovascularization of the host interface or in the donor graft is associated with a significant increase in the risk of allograft rejection. Mittal et al noted such rejection in up to 50% of the grafts with severe vascularization.This was the cause of failure in 36% of optical and 32 % of therapeutic cases in our study.
Alldredge O. C. et al consider younger age of the recipient as factor increasing risk of rejection. In our study 42 % of patients were younger than 40 years.
Fine M et al reported that inflammatory conditions like Herpetic Keratouveitis or bacterial suppuration from a suture abscess may incite an allograft rejection reaction. In our study, infection and /or inflammation was presenting at least 50 % of the cases.
In our study, the incidence of Glaucoma was 24 % in Optical cases and 28 % in therapeutic cases [overall 26%] and it was directly or indirectly contributory to failure.Mittal reported 66.6% failure rate in patients with post keratoplasty glaucoma. In Arentsen's study, uncontrolled glaucoma was the cause of failure in 20 % of the failed grafts; whereas in Wiggin's study, incidence of glaucoma was 16%.
In all these cases, the pupil was not constricted preoperatively. Also all the patients were on high dose systemic and local steroids. Hughes et al have mentioned the real danger of producing posterior sub capsular cataract due to steroids and have reported the incidence of 19%, similar to our study. Summary:-303 5. Rejection rates are higher in cases where the host bed is vascularized and Conjunctival peritomy could be very much helpful in reducing the incidence of rejection rate in these cases prior to Keratoplasty. 6. Older the age of the donor eyeball, greater is the chances of Primary Endothelial Failure [20% in our study with the average age of the donor eyeball being 65 years].