1. 2/22/2016 1 Plasma Knife versus Conventional Scissors for In-situ Excision of Donor Corneoscleral button for the purpose of Penetrating Keratoplasty Ashutosh Agarwal 1, Radhika Tandon 1, Namrata Sharma 1, Jeewan S. Titiyal 1, Rasik B. Vajpayee 1,2 1 Department of Ophthalmology, All India Institute Medical Sciences, New Delhi, India; 2 Centre for Eye Research, University of Melbourne, Melbourne, Australia The authors have no financial interest in the subject matter of this poster.

2. 2/22/20162 Introduction In India Prevalence of corneal blindness is approximately 6.8 million of which about 1 million are bilaterally blind and 40,000 fresh cases are added every year. Nearly 3.5 million good quality cornea donors are required, quite challenging with an annual meagre collection of 20,000 eyes. Rajesh Sinha, Namrata Sharma et al.Corneal Blindness—Present Status I CATARACT & REFRACTIVE SURGERY TODAY,OCTOBER 2005: 59-64 Major obstacles include ineffective procurement of donated corneas as also failure to successfully convince the potential donors. Tandon et al.. Factors Affecting Eye Donation From Postmortem Cases in tertiary Care Hospital (Cornea 2004;23:597–601) In situ excision of donor cornea (compared to conventional W hole Globe Enucleation) ) is a 1.newer technique (last one decade) 2.swift and precise extraction with least damage to endothelium 3.prolific in enhancing the quality and utilization of donor corneas by reducing death preservation time

3. 2/22/20163 Author/GroupStudy DesignInfectionTissue QualityComments Rootman et al, Cornea 2007 468 corneas-300 by in-situ & 168 enucleated over 4 yrs Lower incidence mod. to severe haze & folds in DM No difference in mean ECD No difference in tissue trauma level mean ECD Placed in storage medium earlier -- improve the overall initial quality. Everts RJ et al – Retrospective study Cultures of post- PK CorneoScleral rim PPV and sensitivity for predicting subsequent endopthalmitis were both zero Post-op endopthalmitis optimum specimens collected treatment based on known eye pathogens Vishal Jhanji et al, Cornea 2008 Prospective RCT 100eyes—50 in-situ & 50 enucleated Risk of contamination is equally low in skilled hands Initial cell loss and corneal thickness higher 3 mths Post op comparable ECD GC Median VA More Acceptable Review of Literature: In-situ versus Enucleation

4. 2/22/20164 Review of Literature (contd…) Plasma Knife Cutting 1.Safe, quick, atraumatic 2.By tissue ablation 3.Resistance free (minimum tissue traction) 4.No tactile sensation of making incision 5.Tip does not adhere to tissue 6.Lower frequency and power compared to laser 7.Application in a wide range of ocular surgeries Plasma Knife can produce sharp cuts in the cornea while minimal tissue damage seen beyond edges of the incision Peponis et al,Fugo Blade in Corneal Surgery ;Cornea 2006;25;206-208

5. Aims and Objectives Systematic comparative prospective evaluation of two techniques of harvesting donor cornea by in- situ method with respect to: Donor tissue microbiological contamination Corneal endothelium in the donor and also the recipient following transplantation Graft infection Graft outcome in the recipient at three months

6. 2/22/20166 Methodology Donor selection YES Age <60 years DPT < 6 hours NO Aphakia / Pseudophakia Putting on ventilator for long time (>72hrs) Hypotension Recipient Selection Non-vascularized corneal opacity Written consent from legal next of kin

7. 2/22/20167 Methodology Eyes were systematically randomized (Right/Left) for both type (Plasma Knife or Corneoscleral Scissors) and sequence of extraction. The eye cleaned externally with povidone iodine 10% for 3 mins  Irrigation of conjunctival sac with saline  Povidone 10% instilled in conjunctival sac and washed off with saline  The eye cleaned and draped  1 st limbal swab for culture  Gatifloxacin 0.3% eye drops instilled  Cont………

8. 2/22/20168 Methodology After doing 360° peritomy, a scleral incision made (in conventional method) with surgical blade 3mm from limbus taking care not to enter the choroid  Corneoscleral rim excised using curved corneal scissors/ or Plasma Knife  Careful separation of cornea from underlying tissue care not to damage endothelium  Second swab taken(S2)  Eyes put in McKarey Kauffman (MK) medium (transferred to eye bank)  A transparent plastic cap put over the eye

9. 2/22/20169 Methodology Comparative evaluation done for 2 techniques of in-situ excision i.e. Plasma Knife assisted versus conventional scissors Preoperative Evaluation Donor tissue microbiological contamination (before and after excision) Evaluation and grading of donor cornea on Slit Lamp Post operative follow up of graft recipients Post-op. corneal endothelial status Graft status at 3 months in terms of Central Corneal Thickness, Graft Clarity and Spectacle Corrected Visual Acuity Any associated complications like graft infection/ graft failure etc.

10. RESULTS: Donor Evaluation Comparative EvaluationPlasma Knife Scissors Statistical Coefficient No. of Donors 15(13+2 single eyed donors) 13 p= 0.597 (FET) Median Age (years)50 p=0.889 (MWT) Endothelial Cell Density (cells /mm 2 )2181.27±286.302103.15±186.75 p=0.409 (MWT) Death Preservation Time (hrs)4.70± 1.39 4.75 ±1.48 p=0.924 (MWT) Baseline Microbial Contamination (before extraction) 11/1510/13 p= 0.843 (CST) Microbial Contamination after extraction 9/157/13 p= 1.00 (FET) FET=Fischer Exact Test, MWT=Mann Witney Test, CST=Chi Square Test

11. RESULTS: Recipient Evaluation Comparative Evaluation Plasma Knife Day 7 Day 90 Scissors Day 7 Day 90 Statistical Coefficient Endothelial Cell Density 1821±2261633±2451800±193 1639±175 p 7 =0.982 p 90 =0.612 (MWT) Central Corneal Thickness 583.5±26.3560.7±30.1577.0± 21.9586.62± 54.2 p 7 =0.519 p 90 =0.240 (MWT) Median Graft Clarity3+4+ p 7 =0.082 p 90 =0.686 (FET) Mean Spectacle Corrected Visual Acuity 0.101±0.070.305±0.120.091±0.090.315±0.23 p 7 =0.500 p 90 =0.667 (MWT) Graft ComplicationsNil Graft Infection (Pseudomonas) Nil p=0.464 (FET) FET=Fischer Exact Test, MWT=Mann Witney Test, CST=Chi Square Test

12. 2/22/201612 Conclusion Plasma knife is a safe and effective equipment for in-situ extraction of donor corneoscleral rim.