Visual rehabilitation of aphakia – The Indian perspective.

Aim of study: To evaluate efficacy of surgical intervention in patients having aphakia by secondary IOL implant and to study their complications.Design: A time bound study for management of aphakia in the department of ophthalmology , SAIMS Indore from Feb. 2004 to Feb. 2012. Method: After clinical evaluation on individual basis, we carried out a secondary procedure on thirty two eyes of thirty one patients from age group twenty-six months to seventy four years. Placement of implant in posterior compartment was given first priority in cases of aphakia reporting on out patient basis. In cases where cataract surgery was eventful or could not be completed we preferred doing in the bag placement.If this was not feasible then placement of haptic in ciliary sulcus was the next preferred choice.In the event of pre-existing PAS or insuffecient iris ,we chose to do scleral fixation. In absence of these with inadequate capsular support, anterior chamber placement of lens was done . Power of intraocular lens was calculated by SRK formula. In all cases, except one ab externo, a scleral tunnel was made or previous tunnel used for implantation, depending on duration elapsed between cataract surgery and secondary implantation. Best corrected visual acuity for distance and near was determined at the end of six weeks. In traumatic cases A-Scan biometry was done after six weeks using aphakic mode. Undercorrection of implant power in paediatric patients was done according to age. Result: On the basis of visual acuity recorded patients were categorized into three groups. Twenty four (80%) patients achieved BCVA of 6 /18 or better, four(13.3%) patients gained vision between 6/24 to 6 /60 while two (6.6%) had visual acuity between 3/60 to 5/60. Mean spherical refractive correction was - 0.616 , mean value of cylinder was -0.742 ,which is considerred the most optimal and desired outcome after IOL implantation. Conclusion: Though secondary intervention was done in eyes where ocular tissues had undergone prior surgical handling , inclusive of patients with poor visual prognosis, still 80% could achieve BCVA 6/18 or better. This shows that secondary implantation is an effective means of rehabilitating aphakic patients. Traumatic cases should better be dealt with by a sequential approach.

Secondary Intraocular Lens Implantation in Aphakia

The secondary implantation has gradually increased year by year. The authors conducted a study on eighty-two patients(92 eyes) recieving secondary intraocular lens implantation from Jan 1989 to Jan 1993. Sulcus fixation of posterior chamber IOL implantation was done in cases of intact or small posterior capsule rupture(56 cases). Anterior chamber intraocular lens(8 cases) and posterior chamber intraocular lens implantation by scleral fixation(28 cases) was done in eyes with large posterior capsule rupture or no zonular support. Final postoperative visual acuity of 0.5 or better was acquired in 77 eyes(83.7%) and didn't show statistically significant difference in three groups. The postoperative complications induced IOL decent ration(9.8%), uveitis(6.7%), cystoid macular edema(3.3%), vitreous hemorrhage(3.3%), and retinal detachment(3.3%). The causes of postoperative decreased visual acuity were cystoid macular edema(2.2%), fibrous membrane on IOL(2.2%), IOL decentration(1.1%) and IOL dislocation(1.1%), No statistically significant difference was noted in postoperative central corneal endothelial cell loss in three groups.

New Technique of Implantation of Posterior Chamber Intraocular Lens in the Absence of Capsular Support: 4 Step Test for Sulcus Fixation

In the aphakic eye of no posterior capsular support, the posterior chamber intracoular lens implantation with suture fixation of the haptics to the sclera at the ciliary sulcus have been popular method. But there are difficulty to know whether the hclptics are exactly fixated in the ciliary sulcus or not and more surgical techniques are required. We have devised a simple and safe methods -4 step test (Guiding up test, Spring test, Knocking test, Lifting and rotating test) for implantation of posterior chamber intraocular lenses in the absence of capsular support with or without suture fixation. We have used this surgical technique for implantation of posterior chamber intraocular lenses in 41 eyes with no capsular support at Kim's eye clinic from July, 1989 to December, 1990. The patients were devided into 3 group-without scleral fixation group (Group A), with superior one point scleral fixation group (Group B), with two point scleral fixation groups (Group C). The results were as followed: 1. Follow up ranged from 6 months to 15 months. 2. The postoperative visual acuity was maintained or improved in 11 eyes (91.6%) of Group A, 9 eyes (69.2%) of Group B, and 12 eyes (75%) of Group C. 3. The most common complication was cystoid macular edema and the others were decentration, hyphema, retinal detachment, ocular hypertension in that order.