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Primary Versus Secondary Implantation of Intraocular Lenses in Children - A Short Term Study Abdalla F. El Sawy, Mostafa A Haikal, M. Hany A. Salem,and Ayman A. Hamed Purpose : To compare the results obtained after primary intraocular lens (I.O.L.) implantation with posterior capsulotomy and anterior vitrectomy versus the results obtained with the same technique done secondarily in aphakic eyes of children (2 mon15 y). Methods : In the 1st. group (100 eyes) a routine extracapsular cataract extraction, peripheral iridectomy, posterior chamber (P.C.) 1.0.L., pars plana (or pars plicta) posterior capsulotomy (central 5-6 mm) and anterior vitrectomy were done . In the second group (20 eyes) a pars plana /plicata lensectomy and anterior vitrectomy were done, 1-2 month later a secondary I.O.L. implantation were done . Results : The difficulties, the complications and the corrected visual outcome were discussed. The overall results ensured a clear papillary area, minimal postoperative complications and a favourable visual outcome in all cases . The difficulties were more considerable in secondary implanted cases thanthose with primary implantation . The postoperative reaction in primary implanted cases was a little more than those with secondary implantation . Conclusion: primary posterior chamber lens implantation with primary posterior capsulotomy and anterior vitrectomy is the preferred technique in children; however, it needs more follow up. Key words: Cataract in children, Secondary I.O. L, Pars plana Posterior capsulotomy. BULL. OPHTHALMOL. SOC. EGYPT, 1997; VOL. 90, NUMBER 2, 259-263 Visual rehabilitation of unilaterally aphakic children remains therapeutically challenging. The options available are contact lenses, epikeratophakia and intraocular lenses . Each of these methods has associated problems that make them less than ideal. (9) Of the four options, intraocular lenses have the greatest potential for restoring normal vision. In the last twenty years the intraocular lenses (pseudophakia) have been used for the correction of aphakia. They have many practical advantages over contact lenses and there is no doubt that their optical effect is superior. A well fixed and a well centered lens implant produces a stable retinal image with stable space localization. Pseudophakia, also can be so made as to give the unilateral aphakic patient a fair chance of iseikonia or at least of a minimui.n and tolerable aniseikonia. Implants thus offers the best chance of re-establishment of binocularity in cases of unilateral aphakia. In children in whom binocularity is so readily lost and so hard to restore, there is strong indication for the. use of implants (4) . Secondary intraocular lens implantation in children after contact lens failure may provide some indications for the implantation (14) Secondary intraocular lens implantation in a child after a preliminary cataract extraction can be an advantageous technique . The complications of cataract extraction can be dealt with separately if they occur, and the I.O.L. is not implanted except when the eye is free of any complications.The power of the I.O.L. is more easily determind by simple refraction provided that the pupillary area is clear (8). Patients and Methods One-hundred and Twenty eyes of ninty five children aged from two months to fifteen years were Department of Ophthalmology, Benha Faculty of Medicine, 259 Primary versus secondary implantation of intraocular lenses in children - A-short term study Abdalla F. El Sawy, and et.al operated upon. An extracapsular cataract extraction followed by an intraocular lens implantation (primary implantation), posterior capsulotomy and anterior vitrectomy via a pars plana or pars plicata approach was done in 100 eyes of 80 children (60 eyes were congenital and 40 eyes were traumatic) . Secondary intraocular lens implantation was done in 20 aphakic eyes of 15 children (12 eyes were operated upon for congenital cataract and 8 eyes for trawnatic cataract) . The intraocular lens (I.O.L.) implanted was made of polymethylmethacrylate (P.M.M.A.), a piano-convex surface, optic part was 6mm, three pieces and the overall size was 14 mm. The I.O.L. power was selected according to biometry or according to the refraction of the other eye . All patients were subjected to full ophthalmological examination including, relative and absolute visual acuity of the affected eyes if possible, intraocular pressure measurement by applanation or by Schiotz tonometer (under general anaesthesia in very young patient), biomicroscopic examination using slit lamp, fundus examination and ultrasonography to examine the inside of the eye in case of dense cataract and to determine the needed power of the implant . fixed over the capsular remenants. 10/0 prolene sutures was used for scleral fixation technique under a lamellar scleral flap fashioned at 10 and 4 o'clock meredians Post operative regular examinations for any complications, residual error of refraction and visual acuity was measured by snellen's test, by acuity card procedure or by observing ocular motor fixation pattern in very young patients . Follow-up was done weekly for one month, then monthly for at least three months. Earlier cases was followed for one year Results In primary implanted cases there were no operative difficulties except the occuralice of sever hypotony during vitrectomy, this was rapidly compensated and the intraocular pressure was restored by increasing the rate of fluid infusion. There was no operative complications . In secondary implanted cases there were many operative difficulties . Five cases were presented with posterior synechie and synecholysis using either cystitome or iris spatula was done in these cases . Post-operative Complications In primary implanted cases the method used was a routine extracapsular cataract extraction . A 7 mm. sclerocorneal groove incision (1mm. larger than the optic of the implant), anterior capsulotomy was done, then peripheral iridectomy was fashioned, aspiration of the lens matter with a double -way aspiration irrigation canulaā€˛ then the posterior chamber I.O.L. was implanted after the injection of 0.25 ml of 2% methyl cellulose within the capsular bag and in the anterior chamber. The viscoelastic material was washed out, the wound was closed with interrupted 10/0 nylon sutures and then the anterior chamber was reformed with B. S. S . Using a microvitreoretinal (M.V.R.) blade a sclerotomy was done in the pars plana / plicata,the M.V.R.blade was pushed toward the implant centrally to do an incision 4-5 mm. in the posterior capsule, an anterior vitrectomy was done. During vitrectomy an infusion fluid was introduced through a sclerotomy puncture by a 27 gauge needle . Secondary I.O.L. implantation was used in cases for which a pars plana/plicata lensectomy and vitrectomy were done (after an interval of 1 -2 month) the implant was inserted over the capsular remenants in five cases . Two haptic scleral fixation were done in fourteen cases . Single haptic scleral fixation was done in one case, the other haptic was Complication Primary Cases Secondary cases No. No % °A Iritis . Mild . Moderate 72% 21% 14 4 70% 20% 7 7% 2 - Posterior synachiae 42 42% 7 10% 35% - Pupillary distorion 39% 5 25% . Sever 72 21 39 - I.O.L. capture 3 3% 1 5% - Decentration 28 28% 4 20% - Lens precipitates - Retro-pseudophakic 71 5 71% 5% 14 2 70% 10% 1 1% 0 0% opacification or membrane . - 2ry. glaucoma All secondary cases were presented with collapse of the capsular bag. However, sufficient capsular remenants enabled us to insert the implaiit over it in twelve cases. A scleral fixation tecluiique was adopted in seven cases. Both tecluliques were used for implantation in one case (one haptic was fixed over the capsular remena.nts and the other haptic was fixed by a scleral suture). 260 BULL. OPHTHALMOL. SOC. EGYPT, 1997; VOL. 90, NUMBER 2. The most frequently early post operative complication was a fibrinous uvitis . It was severe in seven cases (7%) of primary implantation group and in two cases (10%) of secondary implantation group, it was moderate in (21 %)of primary implanted cases and in (20%) of secondary implanted cases, it was mild in (72%) of primary implanted cases and in (70%) of secondary implanted cases. However, the iritis was easy to control with medications during the first ten days postoperatively. were observed in those patients denoting a visual improvemment . Discussion The technique of management of cataract in children can be divided into three main categories . The first is lensectomy, anterior vitrectomy followed by intraocular lens implantation at a later date (secondary implantation), the second is extracapsular cataract extraction with intraocular lens implantation (primary implantation), the third is extracapsular cataract extraction, primary posterior capsulotomy, anterior vitrectomy with intraocular lens implantation (primar y impl antation)(3) Posterior synechiae were developed in (42%) of primary implanted cases and in (35%) of secondary implanted cases. Pupillary distorsion was occured in (39%) of primary implanted cases and in (25%) of secondary implanted cases . In o ur s t ud y we ad o p t t he te c h niq ue o f extracapsular cataract extraction, I.O.L. implantation, primary posterior capsulotomy and anterior vitrectomy. In this technique there is an advantage of having the lens in place before the posterior capsule is removed. This is the technique also prefered by Buckly et. al, (1993). Pupillary distorsion was found in (39%) of cases of the primary implantation group and in (25%) of cases of the secondary implantation group . Only one case in the primary implantation group was developed a rise of intraocular pressure for which antiglaucoma medications were described and the I.O.P. was controlled. The main drawback to the primary I.O.L. implantation in children is the changing diapoteric power of an infant's eye from birth to the first few years of life . The corneal curvature was found to assume its adult dimensions by eight years of age, the axial length of the infant eye is getting almost the adult length by the second year of life, (10). In our study we assumed to do emm-etropization by giving the exact power needed considering the refraction of the other eye. Decentration of the implant was occured in (28%) of primary implanted cases and in (20%) of secondary implanted cases. Intraocular lens precipitates of mild to moderate degrees were found in (71%) of primary implanted cases and in (70%) of secondary implanted cases. Intraocular lens captures were found in three cases (3%) of the primary implantation group and in one case (5%) of the secondary implantation group. Most cases of primary and secondary implantation showed a clear pupillary area. Only five (5%) of primary implanted cases and two (10%) o f seco nd ary i mp lanted cases d evelop ed a retropseudophakic membrane formation which necessitated another secondary surgical interference for further vitrectomy. Van Ballen (1988), compared the axial length of twenty seven pseudophakic eyes in children to their contralateral normal eye at the time of intraocular lens implantation and then ten years later. No marked difference was found and the pseudophakic eye seemed to have a normal course of emmetropization, provided the eye attained sufficient visual acuity . All cases have achieved an improvement of visual acuity especially those wit h traumatic cataract. In the primary implantation group, five cases have achieved a corrected visual acuity of 6/9, three cases have achieved a visual acuity of 6/12, twelve cases have achieved a visual acuity of 6/18, and sixteen cases have achieved a visual acuity of 6/24. In the secondary implantation group the best corrected visual acuity achieved was 6/12 in three cases. Two cases has achieved a visual acuity of 6/18 and another two cases has achieved a visual acuity of 6/24 . In the younger age patients the improvement of visual acuity is difficult to assess, however, an improvement of the fixation pattern EI-Sada, (1987) reported that secondary I.O.L. implantation in a child after a preliminary cataract extraction can be advantageous technique. The complications of cataract extraction can be dealt with separately if they occur, and the I.O.L. is not implanted except when the eye is free of any complications . He added that, the power of the I.O.L. is more easily determined by simple refraction provided that the pupillary area is clear . This technique is also adopted by Aron and Aron Rosa, (1983), they mentioned that,implantation in a quit, healed, aphakic eye offers the best chance for functional succes . 261 Primary versus secondary implantation of intraocular lenses in children - A-short term study Abdalla F. El Sawy, and et.al visual acuity of 20/40 or better in 85.3% (29 of 34 One of the most frequent postoperative eyes) of traumatic cataract and in 80% (8 of 10 eyes) complications encountered in this study was iritis, it of congenital cataract was found by a variable degrees in both primary and secondary implantation groups. However, it was Conclusion little more in prima ry than in secondary Secondary implantation after an initial cataract implantation group. surgery is seemed to be techniqually difficult This is agreed with the findings of Aron and becouse of synechiae and adhesions between the Aron Rosa, (1983) who encounter more infim remenants of anterior and posterior capsules. The matory reaction with extracapsular cataract postoperative reaction is nearly the same in primary extraction and primary I.O.L. implantation. implantation and in secondary implantation, however it is little more in primary than in El-Sada, (1987) reported that the fibroblastic secondary implanted cases. The visual results is reaction characteristic of children's eye were found nearly the same in both groups . However, it is little to be less severe among his secondary implanted better in primary than in secondary implanted cases . He attributed this to the short operative cases . The overall results make us to conclude procedure required and to the relatively fewer that primary implantation technique with manipulations inside the eye once cataract posterior capsulotomy and anterior vitrectomy is the extraction was already done . preffered technique than the secondary implantation technique. The high incidence of iritis may be due to irritation by the residual lens matter,or performing References an iridectomy,another explanation was suggested by I. Ahmad Y.B. ; Luey S.H. ; Mahmoud Y.B. and Krause, (1985) is that the iris seems to be to a Samir S.S.: Evaluation of the results of variable degree resistant and sensitive to contact intraocular lens implantation in Egyptian with the parts of the intraocular lens implant children . Metab-Paediatr-Syst-Ophthalmol. especially in younger age group . (1994) :17(1-4): 14-8. Sinsky, et al., (1989) suggested that, in 2. Aron J. and Aron Rosa D. Intraocular lens secondary implantation it is difficult to fixate the implantation in unilateral congenital cataract . A I.O.L. in the bag, therefore, he considered it a preliminary report. Am. Intraocular Implant Soc. disadvantage of secondary implantation J. (1983): 9 : 306 . The problem that confront the surgeon is how to 3. Basti S. ; Ravishankar U. and Gupta S. Results of maintain a clear pupillary area . We have achieved a a prospective evaluation of three methods of clear pupillary area in (95%) of cases of primary management of paediatric cataracts. implantation and in (90%) of cases of secondary Ophthalmology. May (1996): 103(5): 713-20. implantation. This is due to proper posterior capsulotomy and anterior vitrectomy which were 4. Binkhorest C.D. and Gobin M.H. Injuries to the done . Korozwisk et al., (1995) reported that, eye with lens opacity in young children. posterior capsular opacification was occured in Ophthalmologica (1964): 148:169. 36.6% of his cases and this necessitated a 5. Birdtova E. and Krause H. Implantation of N e o d ymi u m Y A G l a se r o r i n s t ru me n t a l intraocular lenses in children. Cesk-Slovecapsulotomy. Oftalmol. Apr. (1995): 51(2): 75-82. In this study a useful vision were maintained in 6. Buckley E.G. ; Klombers L.A. Seaber J.H. and (80%) of cases of primary implantaion group and in Minzter R. Management of the posterior capsule (70%) of cases of secondary implantaion group. We during paediatric intraocular lens implantation . noticed that cases of traumatic cataract have Am. J. Ophthalmol., (1993):15: 115(6). achieved a better corrected visual acuity than those with congenital cataract, this may be due to the 7. Crouch E.R.JR ; Pressman S.H. ; and Crouch amblyopia which may occur in these cases and this E.R. Posterior chamber intraocular lenses; longis agreed with the results of Ahmad et. al., (1994) tenn results in paediatric cataract patients. J. who stated that I.O.L. in traumatic cataract gives the Paediatr - Ophthalmol - Strabismus. Jul-Aug ; best results as regards the visual acuity than those (1995) : 32(4) : 210-8 . with congenital cataract . 8. El-Sada M.A. Secondary intraocular lens The visual results is nearly the same results implantation in children. Bull. Ophthalmol. obtained by Birdtova and Krause, (1995) who Soc. Egypt: (1987) : vol. 180, 337-39. recorded in their study a visual acuity of 0.5 or better in 81.8% of their studied cases . Crouch et.al., (1995) recorded a success rate of post operative 262 BULL. OPHTHALMOL. SOC. EGYPT, 1997; VOL. 90, NUMBER 2. 9. Hiles D.A Infantile cataract, in : Ginsberg, S. ed .cataract and i nt r ao c u lar le n s s ur ger y. Birmingham, Alabaina: (1984) : Aesulapius. 501 :26.. 10. Inagaki Y.: The rapid change of corneal curvature in the neonatal period and infancy . Arch. Ophthalmol., (1986) 104: 1026. 11-Koraszewska M.B. ; Samochwiec D.E. and Pieczara E. Condition of the posterior capsule in pseudophakia in children. Klin-Oczna. Jull-Sep (1995) ; 97(7-8): 227-9. 12. 263 Krause U: Effect of lens implants on iris fluorescein angiography and iris pigment layer. Ophthalmologica . (1985) 63 : 369 . 13. S i n s k e y R . M . ; K a r e l F . a n d D a l R . E . Management of cataracts in children. J. Cataract-Refract-Surg. Mar (1989):; 15(2): P. 196-200. 14. Taylor D.: Monocular infantile cataract, intraocular lenses, and amblyopia. Br. J. Ophthalmol ; (1989) 78, 857-858. 15. Van Balen A.M.: The implantation of artifical lenses in traumatic cataract in children . Doc. Ophthalmol., Proc. Ser. (1988) ; 6: 1-5 .