1. Title slide Surgical Peculiarities in Cases of Irido- fundal Coloboma Having Cataract Extraction Prof Sudarshan K. Khokhar, MD Dr Sanjay K. Mishra, MS Authors have no Financial interest

2. Purpose: To highlight the per operative peculiarities in cases of irido-fundal coloboma undergoing cataract extraction

3. Introduction Irido-fundal coloboma occurs as a result of failure of closure of embryonic fissure in 6 th to 8 th week of intrauterine life. There may be associated dysgenesis of lens zonules when it is pseudonymously termed lenticular coloboma. Cataract occurs early in such eyes and may be a posterior subcapsular variant or dense nuclear cataract. Laxity of capsule and zonules add further to problems during cataract surgery. Moreover placement of intraocular implant has problems with stabilization and centration.

4. Methodology 20 surgical files of cases of irido-fundal coloboma with cataract surgery were studied. Various surgical problems encountered during per operative stage were documented and ways to counter them were discussed. Cases with extreme subluxation were subjected to pars plana lensectomy and vitrectomy.

5. Results 20 eyes of 20 patients undergoing cataract surgery were studied. 14 were males and the age ranged from 20 yrs. to 35 yrs. All eyes had cataract with nuclear sclerosis grade 2 to grade 3. posterior subcapsular component was present in most of cases ( 12 out of 20 eyes). {Fig. 1,2}. 18 of 20 eyes (90%) underwent phaco-emulsification surgery with intraocular lens implant. Due to associated subluxation 2 eyes were approached from pars plana route with lensectomy and vitrectomy done. Three eyes had about 3 clock hours subluxation and they were successfully managed with capsular tension ring (15%). The most common problem encountered was with completion of anterior capsulorrhexis. Due to weakness of zonules and laxity of capsule anterior capsulorrhexis tends to slip away. {fig.3}. However this problem when anticipated early can be managed by Utrata forceps which gives better control over the same. {fig.4}. These cases were of harder grade as compared to age related cases. However there was no difficulty during fragmentation of nuclei and neither during emulsification. {fig.5}.

6. During aspiration of cortical matter, there was difficulty in area adjacent to zonular weakness, but this was managed with bimanual irrigation and aspiration technique. Placement of intraocular lens implant in cases without lenticular coloboma was uncomplicated. {fig. 6}. However it posed a challenge specially in cases with subluxation and zonular weakness (lenticular coloboma). The haptic of these lenses needed to be placed perpendicular to area of coloboma else IOL became decentered. {fig. 7,8}. In fifteen eyes (75%), foldable acrylic lenses were implanted and in 3 cases (15%), single piece PMMA IOL (5.25 mm optic) were implanted. Two cases in which pars plana lensectomy and vitrectomy was done, no IOL was implanted. All cases in which rigid PMMA IOL were implanted, wound was secured with single 10’0 monofilament nylon suture. In the 3 cases where CTR was put, it was done after removal of cortical matter and before implanting IOL. {fig. 9, 10}. None of the cases during follow up of 6 months developed any retinal complication like break or detachment.

7. Conclusion The results of this small case series affirm that clinically significant cataract may be associated with congenital coloboma and present at early age group than normal age related cases with significant deterioration of already compromised vision. Surgeries in such cases are challenging and needs to be mastered. Cataract surgery and IOL placement are safe in such cases and may be a partially sight restoring procedure in these anomalous eyes. It also allows better evaluation and treatment of retinal pathology

8. Figures Fig. 1 Posterior sub capsular cataract Fig. 2 Sclerotic cataract

9. Rhexis running off in the area of lenticular coloboma Rhexis completed by Utrata forceps Fig. 3 Fig. 4

10. Fig. 5Fig. 6

11. Fig. 7 decentered IOL Fig. 8 centered IOL

12. Fig. 9Fig. 10 Capsular Tension ring being inserted