Advances in the management of the surgical complications for congenital cataract

Abstract

The greatest concern in children with cataracts is irreversible visual loss. The timing of congenital cataract surgery is critical for the visual rehabilitation. Cataract surgery in children remains complex and challenging. The incidence of complications during or after operation is higher in children than adults. Some complications could be avoided by meticulous attention to surgical technique and postoperative care, and others were caused by more exuberant inflammatory response associated with surgery on an immature eye or the intrinsic eyes abnormalities. Utilizing of advanced techniques and timely applying topical corticosteroids and cycloplegic agents can reduce the occurrence of visual axis opacification. Operation on children with strabismus or nystagmus, and applying occlusion therapy on amblyopic eyes can balance the visual inputs to the two eyes. Diagnosis of glaucoma following congenital cataract surgery requires lifelong surveillance and continuous assessment of the problem. So cataract surgeries in children are not the end of journey, but one step on the long road to visual rehabilitation. This paper describes recent evidence from the literature regarding the advance of management after congenital cataract surgery.

Keywords

cataract/congenital / surgery / cataract/complication

Introduction

The aim of the pediatric cataract surgery is to provide and maintain a clear visual axis and a focused retinal image. Children have reduced sclera and corneal rigidity, more inflammation after surgery, and a propensity to develop reopacification of the visual axial [1]. The treatment of pediatric cataracts is a difficult and continuously evolving area in the ophthalmology. Ophthalmologists treating this special group of patients should be experienced and comfortable with the potential problems related to these children [2].

Advances of surgery

The surgical treatment of pediatric cataracts is a constantly evolving area in ophthalmology [2]. Now, the procedures are performed as the manual continuous curvilinear capsulorhexis (CCC) of anterior capsule, and then the lens material are removed using a vitrectomy handpiece, phacoemulsification handpiece, or automated irrigation and aspiration handpiece after hydrodissection. Posterior continuous capsule capsulorhexis (PCCC) and anterior vitrectomy are performed for patients younger than 8 years of age. Intraocular lens (IOL) implantation is performed in children older than 1 year of age with unilateral cataract and in those older than 2 years of age with bilateral cataract [3,4].

The basic technics of lens removal have not changed greatly in recent years other than the use of the 23-gauge or 25-gauge vitrectomy system [5,6]. The pars plicata entry is made 1.0 to 1.5 mm behind the limbus. It can be used to create a posterior capsulectomy of a desirable size in a controlled manner to avoid destabilization of the IOL. Lentectomy was performed via a pars plana or pars plicata approach using the 23-gauge or 25-gauge vitrectomy system. Vasavada and Meier reported that pars plana/plicata lentectomy using 23-gauge instruments is a safe, effective, and minimally invasive method for treating cataract in babies [7,8].

Postoperative complications

A much higher incidence of complications occurs in children after cataract surgery than in adults. Whereas some complications are preventable by meticulous attention to surgical technique and postoperative care, others arise due to the intrinsic abnormalities of these eyes or the more exuberant inflammatory response associated with surgery on an immature eye. The incidences of postoperative complications for congenital cataract among different Asiatic countries/regions are shown in Table 1.

Amblyopia and refractive correction

Amblyopia is the greatest threat to vision following infantile cataract. Screening with early detection followed by surgery before the end of the third month is important to decrease the risk of marked acuity loss [12]. Individual visual acuity development is related to age at surgery and type of cataract. In spite of optimized care and surgery before 9 months, the best-corrected visual acuity (BCVA) was subnormal compared to healthy children [12]. Total or unilateral cataract, nystagmus or strabismus, and inadequate amblyopic therapy were predictors of poor BCVA [13]. More than two-thirds of congenital cataract children did not develop acuity better than 0.6 LogMAR in aphakic eye [14]. Significant myopic shifts occurred especially in infants in the first year of surgery [13]. Final refraction in the unilateral cataract was significantly more myopic than in the bilateral cataract [15].

Thoumazet reported that primary intraocular lens implantation provides significantly better final visual acuity than aphakic contact lens-corrected eyes and provides better stabilization over time whatever the age [16].The best acuities were achieved in the eyes which had been treated with early primary IOL, but they had a higher rate of complications, thus requiring reoperation [15]. In the Infant Aphakia Treatment Study (IATS), the rates of intraoperative complications (ICs), adverse events (AEs), and additional intraocular surgeries (AISs) 1 year after surgery were numerically higher in the IOL group than in the aphakia group, but their functional impact does not clearly favor either treatment group [17,18].

Occlusion therapy is started in unilateral cases as soon as the media is clear and the aphakia is corrected. In cases with bilateral cataract, occlusion therapy does not usually need to be as aggressive as in unilateral cases, and is sometimes useful if one eye is more amblyopic than the other. Close follow-up is mandatory until the patient is 7 years of age [19]. Adherence to patching during the first 6 months after surgery is associated with better grating visual acuity at 12 months of age after treatment for unilateral cataract and implanting an intraocular lens is not associated with adherence [20]. The type of correction (intraocular lens vs. contact lens) was not associated with the amount of patching achieved, whereas family socioeconomic status and maternal stress appeared to play a role [21].

Glaucoma

Development of glaucoma in aphakia and pseudophakia after congenital cataract surgery is multifactorial. The risk factors include the age at surgery, pre-existing ocular abnormalities, type of cataract, and the effect of lens particles, lens proteins, inflammatory cells, secondary membrane surgery, microcornea, primary posterior capsulotomy with anterior vitrectomy, and retained lens material [22–24].

Characteristics of early-onset and delayed-onset glaucoma were described by Kang et al. [25]. Of the twenty-four patients (37 eyes) identified with glaucoma after cataract surgery, 15 eyes had an early onset of glaucoma (1 week to 13 months after cataract surgery) and 22 eyes had delayed-onset glaucoma (70 to 177 months after cataract surgery). The average interval between cataract surgery and glaucoma onset of early-onset group is 0.16 year and that of delayed-onset group is 11.75 years. Early-onset glaucoma was significantly more likely to be due to angle closure than delayed-onset glaucoma. Mills and Robb [26] noted that glaucoma with an angle-closure mechanism frequently occurs within the first few months after surgery and open-angle glaucoma has a later onset (average 7.4 years). Asrani reported an average interval between pediatric cataract surgery and the onset of open angle glaucoma of 12.2 years [27]. Open-angle glaucoma was the most common type of aphakic glaucoma [28]. Asrani reported a decreased incidence of open-angle glaucoma in pseudophakic eyes compared to aphakic after cataract surgery [27]. Some eyes have some degree of peripheral anterior synechiae. Some eyes showed increased pigmentation and a glazed appearance of the trabecular meshwork. Closure glaucoma occurs most commonly in the immediate postoperative period in microphthalmic eyes secondary to pupillary block. Papillary block is usually caused by a fibrin membrane extending across the pupil [28].

Some patients with glaucoma associated with aphakia or pseudophakia may achieve long-term control of intraocular pressure (IOP) with medical therapy alone. Topical corticosteroids and cycloplegic agents administered postoperatively will prevent a papillary membrane from forming in most infantile eyes [29]. The Nd:YAG laser is particularly useful for iridotomy in pupillary block glaucoma in children. A significant proportion of patients required surgical intervention to control IOP [22,29]. Surgical iridectomy is advisable when laser iridotomy fails repeatedly, especially in patients with severe postoperative inflammation. Glaucoma drainage implants are useful when other surgical treatments have a poor prognosis for success, prior conventional surgery fails, or when significant conjunctival scarring precludes filtration surgery [22]. Children who have undergone cataract surgery should have a long period follow-up, since the continuing risk of developing glaucoma accompanies throughout their lives.

Modern surgical techniques do not eliminate the early development of glaucoma following congenital cataract surgery with or without an intraocular lens implant. In the IATS, younger patients seem more likely to develop a glaucoma-related adverse event in the first year of follow-up. Vigilance for the early development of glaucoma is needed following congenital cataract surgery, especially when surgery is performed during early infancy or for a child with persistent fetal vasculature [30].

Strabismus and nystagmus

Strabismus is often the presenting sign of a child with a unilateral cataract and is also frequently present preoperatively in children with bilateral cataracts. Esotropias are more commonly observed in children with congenital cataracts while exotropias are observed more frequently in children with acquired cataracts [31]. Strabismus is also a frequent complication following bilateral cataract surgery in childhood. The mean interval between the time of cataract extraction and the diagnosis of strabismus was 32.5 months in the patients with exotropia and 35.6 months in the patients with esotropia [32]. Park et al. concluded that the children undergoing bilateral cataract surgery should be followed up carefully for the development of strabismus, especially at an early age. Birch et al. [33] studied 41 children who had undergone extraction of dense cataracts by the age of 5 years. They found that congenital onset was associated with significant risk for strabismus; infantile onset was associated with significant risk for nystagmus. Duration>6 weeks was associated with significant risk for both strabismus and nystagmus. Congenital onset was associated with significant risk for interocular asymmetry in severity of nystagmus, as was unilateral cataract. Early strabismus surgery and optical correction may be helpful to improve binocularity, especially for older children with acquired cataract [31].

Nystagmus develops commonly in children with dense bilateral cataracts if treatment is delayed. Nystagmus is present in 50% of children with bilateral congenital cataracts and rarely develops in children with monocular cataracts [31]. The presence of nystagmus has been considered as an indicator of poor prognosis in infants with bilateral congenital cataracts. However, Yagasaki reported 10 infants with preoperative nystagmus after simultaneous surgery for bilateral congenital cataracts; of the 10 infants, 5 cases whom were operated on within one month after the onset showed a resolution of nystagmus or reduction to latent nystagmus postoperatively, and the 5 cases who had no postoperative change in nystagmus were operated on later than this period [34].

Posterior capsular opacification (PCO)

PCO is nearly universal in infantile eyes within a few months of surgery if the posterior capsule is left intact. Management of the posterior capsule significantly affects the outcome of pediatric cataract surgery [35]. In children under 6–7 years or in children who have poor cooperation for probable Nd:YAG capsulotomy [36], primary posterior capsulotomy and vitrectomy are considered routine surgical steps to reduce the incidence of PCO, especially in younger children [37]. The aim of PCCC is to try to achieve an opening about 1 mm smaller than the optic of the IOL used [38]. Newer approaches to posterior capsule management include pars plicata posterior capsulorhexis, sutureless vitrectomy, sealed-capsule irrigation, and bag-in-the-lens IOL [39]. Pars plicata posterior capsulorhexis can be used to create a posterior capsulectomy of a desirable size in a controlled manner to avoid destabilization of the IOL [7]. PCCC without anterior vitrectomy was found to be a preferred approach in children above 7 years or for those who cooperate for Nd: YAG laser capsulotomy at later time. The posterior capsule should be left intact in children above 9–10 years or in those who cooperate for laser treatment [37]. In-the-bag IOL implantation could provide a good centration and reduce the chance of PCO [38]. Acrylic IOL seems to induce less PCO than polymethyl methacrylate (PMMA) IOL. The site of IOL fixation and the surgical technique used also affect the prevalence of PCO [39].

Decentralization of the pupil

Incarceration of the iris in the wound is sometimes encountered. Pupillary irregularities are particularly common after IOL implantation secondary to posterior synechiae [40]. In some instances, the vitreous-cutting instrument damages the iris sphincter muscle intraoperatively. In other instances, the iris may prolapse out of the scleral incision. Vitreous extending to the surgical incision may also cause linking of the pupil. To avoid this complication, a rather long tunnel is recommended during cataract extraction and suture should be used to close the wound. Careful surgery is also helpful to leave the iris without trauma. If the visual axis is covered with iris, it is important to promptly reposition the iris or make a new central pupil with surgical intervention or Nd:YAG laser treatment [41].

Secondary membrane

Secondary membrane may form across the pupil or over the anterior or posterior surface of an IOL after infantile cataract surgery [40]. These can be particularly common in microphthalmia and in eyes with excessive intraoperative iris manipulation [42]. When these membranes are relatively thin, they may be opened by a YAG laser. In more serious cases, intraocular surgery may be required. There are several approaches to reduce the incidence of secondary membrane, such as minimizing the manipulation of the iris, applying topical corticosteroids and cycloplegic agents at frequent intervals postoperatively, by using heparin in the infusion solution.

Since postoperative intraocular inflammation is much more severe in children after cataract surgery and the formation of fibrinous membrane is not unusual, subconjunctival steroids and antibiotics are frequently used at the end of surgery, together with intensive topical steroid therapy postoperatively. Topical prednisolone acetate 1% every hour to 4 hourly is commonly used, occasionally in conjunction with oral steroids [38]. And mydriatic eye drop are important in preventing posterior synechiae and reducing the chance of papillary block.

IOL decentration

Decentration of an IOL is not uncommon after IOL implantation during infancy. It has been reported to have prevalence of 40% in pediatric eyes following posterior chamber IOL implantation [43]. Sometimes, explanting or repositioning an IOL may be necessary.

A prospective study was conducted on 90 eyes undergoing extracapsular cataract extraction and posterior chamber IOL implantation. Postoperative IOL decentration was evaluated with respect to the loop material, either polypropylene (prolene) or polymethylmethacrylate (PMMA), and the IOL fixation technique, either in the capsular sac (in-the-bag) after capsulorhexis, or in the ciliary sulcus after “can-opener” capsulotomy. More decentration was observed with IOL having polypropylene loops than with those having PMMA loops. IOL implanted in the bag showed greater decentration than those implanted in the sulcus, but the difference was not significant [44]. Their findings confirm the recommendation to use an IOL with PMMA loops when placing the implant in the capsular sac.

Fibrinoid reaction

Because of the high degree of inflammation in children, fibrin in the pupil can be found even when an IOL with high biocompatibility has been implanted. Fibrinoid reaction can be minimized by applying topical steroids and mydriatics frequently. Wilson et al. [45] reported that heparin sodium in the irrigating fluid helped to prevent postoperative inflammation. In some instances, Nd:YAG laser treatment may be helpful to clear the visual axis. Posterior synechiae formation in the postoperative period is common, especially in the newborn when no IOL has been implanted [41].

Corneal astigmatism and corneal edema

Corneal astigmatism [46,47] is recognized as a problem arising from cataract surgery. Postoperative astigmatism is of greater importance in children than in adults because of its adverse effect on vision development and the risk of amblyopia. Children show a significant spontaneous reduction in astigmatism postoperatively, especially during the first 5 months of follow-up [46,48], and less astigmatism occurs in children having surgery under 3 years.

Corneal edema is usually caused by prolongation of surgical procedure, secondary to detergent left on surgical instrument or cannulas. Glaucoma can accentuate the increase of central corneal thickness (CCT) [49]. Shortly after cataract removal, the CCT was significantly greater in aphakic eyes than in pseudophakic eyes [50]. Corneal edema can resolve within a few days after cataract surgery.

Intraocular inflammation and endophthalmitis risk

Because very large series of patients are required to determine the incidence of endophthalmitis, it may indeed be difficult to obtain this information. Good [51] described that 3 cases of endophthalmitis in 671 pediatric cataract surgeries.

The information available on the risks of simultaneous bilateral cataract surgery is even more limited. Kushner indicated that others had reported endophthalmitis after simultaneous bilateral cataract surgery in children ranging from 7 per 10 000 to 45 per 10 000. He only provided anecdotal evidence to support his assertion that simultaneous bilateral cataract surgery increases the risk of developing bilateral endophthalmitis. And Kushner asserted that cost saving was not the overriding consideration in deciding whether to perform sequential or simultaneous bilateral cataract surgery. However, if all other factors are equal, cost saving could be a compelling reason to favor one approach over the other [52,53].

Nihalani indicated that the prevalence of any corneal edema (54% vs. 19%, P = 0.04) and uveal inflammation>2+ (92% vs. 31%, P<0.05) in immediate postoperative period was greater with sulcus IOL than in-the-bag placement. Secondary in-the-bag IOL showed less inflammation and corneal edema in the early postoperative period [54].

Retinal hemorrhages and retinal detachment

Retinal detachment after congenital cataract surgery can appear anytime postoperatively. There is scant literature regarding this issue. The reported average interval between lens operation and retinal detachment is 23 to 34 years [55]. Vasavada reported the incidence of postoperative retinal detachment after modern surgical techniques could be appraised only after follow-up observation for about 30 years [39]. Seven-two percent of the detachments occurred after more than 10 years [55]. High myopia and multiple operations increase the risk of detachment. The advent of the vitrectomy machine reduced the rate of retinal detachment as a late complication [39]. An internal approach for detachment repair is often needed after congenital cataract surgery and high reattachment rates are achieved [55]. Even with new techniques, visual results after retinal reattachment surgeries in the pediatric population, in general, are poor.

A hemorrhagic retinopathy develops in a significant percentage of infants after a lensectomy and anterior vitrectomy. Flame-shaped hemorrhage in the posterior pole can resolve in several weeks without sequelae, but a hemorrhage occurring in the fovea can result in a severe reduction of vision.

Macular edema

Cystoid macular edema is a rare complication in children because of the healthy vasculature. The incidence of cystoid macular edema (CME) is much lower in children after posterior capsulectomy and anterior vitrectomy. Kirwan reported that cystoid macular edema (CMO) was not detected in the early postoperative period irrespective of approach to anterior vitrectomy or presence of an intraocular lens. Intravenous fluorescein angiography was performed without complication [56]. Rao et al. [57] reported the similar conclusion.

References

[1] Trivedi RH, Wilson ME. Pediatric cataract surgery: operative and postoperative issues. In: lson ME, Saunders RA, Trivedi RH. Pediatric Ophthalmology: current thought and a practical guide. Leipzig:. Springer Verlag2009: 311

[2] Hug D. Update on pediatric cataracts and cataract surgery. Int Ophthalmol Clin2010; 50(4): 107-113

[3] Zhang H, Xie L, Wu X, Tian J. Long-term results of pediatric cataract surgery after delayed diagnosis. J AAPOS2012; 16(1): 65-69

[4] Kim DH, Kim JH, Kim SJ, Yu YS. Long-term results of bilateral congenital cataract treated with early cataract surgery, aphakic glasses and secondary IOL implantation. Acta Ophthalmol (Copenh)2012; 90(3): 231-236

[5] Cacciatori M, Arpa P. Surgical technique for anterior segment surgery in pediatric patients using 25-gauge instruments. J Cataract Refract Surg2006; 32(4): 562-564

[6] Chee KY, Lam GC. Management of congenital cataract in children younger than 1 year using a 25-gauge vitrectomy system. J Cataract Refract Surg2009; 35(4): 720-724

[7] Vasavada AR, Shah SK, Praveen MR, Vasavada VA, Trivedi RH, Karve SJ. Pars plicata posterior continuous curvilinear capsulorhexis. J Cataract Refract Surg2011; 37(2): 221-223

[8] Meier P, Sterker I, Tegetmeyer H, Wiedemann P.23-gauge-lentectomy for the treatment of congenital cataract. Ophthalmologe2010; 107(3): 241-245(n German))

[9] Yang ML, Hou CH, Lee JS, Liang YS, Kao LY, Lin KK. Clinical characteristics and surgical outcomes of pediatric cataract in Taiwan. Graefes Arch Clin Exp Ophthalmol2006; 244(11): 1485-1490

[10] Kim KH, Ahn K, Chung ES, Chung TY. Clinical outcomes of surgical techniques in congenital cataracts. Korean J Ophthalmol2008; 22(2): 87-91

[11] Thakur J, Reddy H, Wilson ME Jr, Paudyal G, Gurung R, Thapa S, Tabin G, Ruit S. Pediatric cataract surgery in Nepal. J Cataract Refract Surg2004; 30(8): 1629-1635

[12] Sjöstrand J, Magnusson G, Nyström A, Jonsson R. Stability of visual outcome from 7 years in children treated surgically for bilateral dense congenital cataracts before 37 weeks of age. Acta Ophthalmol (Copenh)2011; 89(1): 30-36

[13] Lu Y, Ji YH, Luo Y, Jiang YX, Wang M, Chen X. Visual results and complications of primary intraocular lens implantation in infants aged 6 to 12 months. Graefes Arch Clin Exp Ophthalmol2010; 248(5): 681-686

[14] Allen RJ, Speedwell L, Russell-Eggitt I. Long-term visual outcome after extraction of unilateral congenital cataracts. Eye (Lond)2010; 24(7): 1263-1267

[15] Perucho-Martínez S, Tejada-Palacios P, de-la-Cruz-Bertolo J. Congenital cataracts: complications and functional results according to different surgical techniques. Arch Soc Esp Oftalmol2010; 85(1): 16-21(in Spanish)

[16] Thoumazet F, Mauris-Tyson S, Colin J, Mortemousque B. Congenital cataract removed early: long-term visual acuity outcome and refractive changes. J Fr Ophtalmol2010; 33(6): 373-379 (in French)

[17] Russell B, Ward MA, Lynn M, Dubois L, Lambert SR. The infant aphakia treatment study contact lens experience: one-year outcomes. Eye Contact Lens2012; 38(4): 234-239

[18] Plager DA, Lynn MJ, Buckley EG, Wilson ME, Lambert SR. Complications, adverse events, and additional intraocular surgery 1 year after cataract surgery in the infant Aphakia Treatment Study. Ophthalmology2011; 118(12): 2330-2334

[19] Lambert SR, Plager DA, Lynn MJ, Wilson ME. Visual outcome following the reduction or cessation of patching therapy after early unilateral cataract surgery. Arch Ophthalmol2008; 126(8): 1071-1074

[20] Drews-Botsch CD, Celano M, Kruger S, Hartmann EE. Adherence to occlusion therapy in the first six months of follow-up and visual acuity among participants in the Infant Aphakia Treatment Study (IATS). Invest Ophthalmol Vis Sci2012; 53(7): 3368-3375

[21] Drews-Botsch CD, Hartmann EE, Celano M. Predictors of adherence to occlusion therapy 3 months after cataract extraction in the Infant Aphakia Treatment Study. J AAPOS2012; 16(2): 150-155

[22] Mandal AK, Netland PA. Glaucoma in aphakia and pseudophakia after congenital cataract surgery. Indian J Ophthalmol2004; 52(3): 185-198

[23] Rabiah PK. Frequency and predictors of glaucoma after pediatric cataract surgery. Am J Ophthalmol2004; 137(1): 30-37

[24] Kirwan C, Lanigan B, O’Keefe M. Glaucoma in aphakic and pseudophakic eyes following surgery for congenital cataract in the first year of life. Acta Ophthalmol (Copenh)2010; 88(1): 53-59

[25] Kang KD, Yim HB, Biglan AW. Comparison of delayed-onset glaucoma and early-onset glaucoma after infantile cataract surgery. Korean J Ophthalmol2006; 20(1): 41-46

[26] Mills MD, Robb RM. Glaucoma following childhood cataract surgery. J Pediatr Ophthalmol Strabismus1994; 31(6): 355-360, discussion 361

[27] Asrani S, Freedman S, Hasselblad V, Buckley EG, Egbert J, Dahan E, Gimbel H, Johnson D, McClatchey S, Parks M, Plager D, Maselli E. Does primary intraocular lens implantation prevent “aphakic” glaucoma in children? J AAPOS2000; 4(1): 33-39

[28] Chen TC, Walton DS, Bhatia LS. Aphakic glaucoma after congenital cataract surgery. Arch Ophthalmol2004; 122(12): 1819-1825

[29] Comer RM, Kim P, Cline R, Lyons CJ. Cataract surgery in the first year of life: aphakic glaucoma and visual outcomes. Can J Ophthalmol2011; 46(2): 148-152

[30] Beck AD, Freedman SF, Lynn MJ, Bothun E, Neely DE, Lambert SR. Glaucoma-related adverse events in the Infant Aphakia Treatment Study: 1-year results. Arch Ophthalmol2012; 130(3): 300-305

[31] Hoyt CS, Taylor D. Pediatric Ophthalmology and Strabismus: Expert Consult. Elsevier- Health Sciences Division. 2012

[32] Park SH, Na JH, Shin SY. Strabismus following bilateral cataract surgery in childhood. Jpn J Ophthalmol2010; 54(4): 272-277

[33] Birch EE, Wang J, Felius J, Stager DR Jr, Hertle RW. Fixation control and eye alignment in children treated for dense congenital or developmental cataracts. J AAPOS2012; 16(2): 156-160

[34] Yagasaki T, Sato M, Awaya S, Nakamura N. Changes in nystagmus after simultaneous surgery for bilateral congenital cataracts. Jpn J Ophthalmol1993; 37(3): 330-338

[35] Ram J, Gupta N, Sukhija JS, Chaudhary M, Verma N, Kumar S, Severia S. Outcome of cataract surgery with primary intraocular lens implantation in children. Br J Ophthalmol2011; 95(8): 1086-1090

[36] Guo S, Wagner RS, Caputo A. Management of the anterior and posterior lens capsules and vitreous in pediatric cataract surgery. J Pediatr Ophthalmol Strabismus2004; 41(6): 330-337; quiz 356-337

[37] Vasavada AR, Nihalani BR. Pediatric cataract surgery. Curr Opin Ophthalmol2006; 17(1): 54-61

[38] Fan DS, Yip WW, Yu CB, Rao SK, Lam DS. Updates on the surgical management of paediatric cataract with primary intraocular lens implantation. Ann Acad Med Singapore2006; 35(8): 564-570

[39] Vasavada AR, Praveen MR, Tassignon MJ, Shah SK, Vasavada VA, Vasavada VA, Van Looveren J, De Veuster I, Trivedi RH. Posterior capsule management in congenital cataract surgery. J Cataract Refract Surg2011; 37(1): 173-193

[40] Lambert SR, Drack AV. Infantile cataracts. Surv Ophthalmol1996; 40(6): 427-458

[41] Zetterström C, Kugelberg M. Paediatric cataract surgery. Acta Ophthalmol Scand2007; 85(7): 698-710

[42] Harley RD, Nelson LB, Olitsky SE. Harley’s pediatric ophthalmology. In: Tesser RA, Hess DB, Buckley EG. Pediatric cataracts and lens anomalies. Philadelphia: Lippincott Williams & Wilkins. 2005: 371

[43] Hiles DA, Hered RW. Modern intraocular lens implants in children with new age limitations. J Cataract Refract Surg1987; 13(5): 493-497

[44] Fruscella S, Ducoli P, Manni GL. Decentration of posterior chamber IOL: effects of loop material and fixation technique. Eur J Ophthalmol1994; 4(2): 111-114

[45] Wilson ME Jr, Trivedi RH. Low molecular-weight heparin in the intraocular irrigating solution in pediatric cataract and intraocular lens surgery. Am J Ophthalmol, 2006; 141:537-538

[46] Bar-Sela SM, Barequet IS, Spierer A. Vector analysis of high early postoperative astigmatism after congenital cataract surgery. Graefes Arch Clin Exp Ophthalmol2005; 243(9): 881-885

[47] Bradfield YS, Plager DA, Neely DE, Sprunger DT, Sondhi N. Astigmatism after small-incision clear corneal cataract extraction and intraocular lens implantation in children. J Cataract Refract Surg2004; 30(9): 1948-1952

[48] Spierer A, Nahum A. Changes in astigmatism after congenital cataract surgery and intraocular lens implantation using scleral tunnel incision. Eye (Lond), 2002; 16(4): 466-468

[49] Lim Z, Muir KW, Duncan L, Freedman SF. Acquired central corneal thickness increase following removal of childhood cataracts. Am J Ophthalmol2011; 151(3): 434-441 e1

[50] Faramarzi A, Javadi MA, Jabbarpoor Bonyadi MH, Yaseri M. Changes in central corneal thickness after congenital cataract surgery. J Cataract Refract Surg2010; 36(12): 2041-2047

[51] Good WV, Hing S, Irvine AR, Hoyt CS, Taylor DS. Postoperative endophthalmitis in children following cataract surgery. J Pediatr Ophthalmol Strabismus1990; 27(6): 283-285

[52] Lambert SR, Dave H, Phoenix V, Becker ER. Simultaneous vs sequential bilateral cataract surgery for infants with congenital cataracts: weighing the risks of general anesthesia during infancy vs endophthalmitis. Arch Ophthalmol2011; 129(4): 524-525, author reply 525-526

[53] Kushner BJ. Simultaneous cataract surgery for bilateral congenital cataracts: are the cost savings worth the risk? Arch Ophthalmol2010; 128(8): 1073-1074

[54] Nihalani BR, Vanderveen DK. Secondary intraocular lens implantation after pediatric aphakia. J AAPOS2011; 15(5): 435-440

[55] Yorston D, Yang YF, Sullivan PM. Retinal detachment following surgery for congenital cataract: presentation and outcomes. Eye (Lond)2005; 19(3): 317-321

[56] Kirwan C, O’Keeffe M. Cystoid macular oedema in paediatric aphakia and pseudophakia. Br J Ophthalmol2006; 90(1): 37-39

[57] Rao SK, Ravishankar K, Sitalakshmi G, Ng JS, Yu C, Lam DS. Cystoid macular edema after pediatric intraocular lens implantation: fluorescein angioscopy results and literature review. J Cataract Refract Surg2001; 27(3): 432-436

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag Berlin Heidelberg