Pediatric intraocular lens implantation. Surgical results and complications in more than 300 patients

Accuracy of Intraocular Lens Power Calculation Formulas in Pediatric Cataract Patients: A Systematic Review and Meta-Analysis

Background: Among the various intraocular lens (IOL) power calculation formulas available in clinical settings, which one can yield more accurate results is still inconclusive. We performed a meta-analysis to compare the accuracy of the IOL power calculation formulas used for pediatric cataract patients.

Methods: Observational cohort studies published through April 2021 were systematically searched in PubMed, Web of Science, and EMBASE databases. For each included study, the mean differences of the mean prediction error and mean absolute prediction error (APE) were analyzed and compared using the random-effects model.

Results: Twelve studies involving 1,647 eyes were enrolled in the meta-analysis, and five formulas were compared: Holladay 1, Holladay 2, Hoffer Q, SRK/T, and SRK II. Holladay 1 exhibited the smallest APE (0.97; 95% confidence interval [CI]: 0.92–1.03). For the patients with an axial length (AL) less than 22 mm, SRK/T showed a significantly smaller APE than SRK II (mean difference [MD]: −0.37; 95% CI: −0.63 to −0.12). For the patients younger than 24 months, SRK/T had a significantly smaller APE than Hoffer Q (MD: −0.28; 95% CI: −0.51 to −0.06). For the patients aged 24–60 months, SRK/T presented a significantly smaller APE than Holladay 2 (MD: −0.60; 95% CI: −0.93 to −0.26).

Conclusion: Due to the rapid growth and high variability of pediatric eyes, the formulas for IOL calculation should be considered according to clinical parameters such as age and AL. The evidence obtained supported the accuracy and reliability of SRK/T under certain conditions.

Systematic Review Registration: PROSPERO, identifier: INPLASY202190077.

Accuracy of Intraocular Lens Power Calculation in Children With Vitrectomized Eyes Undergoing Cataract Surgery

PURPOSE

To assess the predictability of desired postoperative refractive outcomes using the SRK-II formula for intraocular lens (IOL) power calculation in children undergoing cataract surgery in eyes with a previous pars plana vitrectomy (PPV).

METHODS

In this retrospective study, 68 eyes of 66 children who underwent cataract surgery and IOL implantation in eyes that had previous vitrectomy between January 2008 and December 2017 were included. Data were collected on preoperative and postoperative characteristics. The Mann-Whitney test, Kruskal-Wallis test, and multinominal logistic regression were used for comparing the results.

RESULTS

Absolute prediction error (APE) in the cohort was 1.29 ± 1.13. Desirable refractive outcome with insignificant prediction error of less than 0.50 diopters (D) was found in approximately one-third of the children. Patients were further subdivided by magnitude of APE as ≥ 0.50 to ≤ 1.00 D and > 1.00 D. Age at the time of surgery, axial length, mean keratometry, silicone oil removal, IOL position, scleral buckle, and corneal suture did not affect APE and there was no significant difference between the groups (P > .05).

CONCLUSIONS

The mean APE of the SRK-II formula for IOL power calculation in pediatric eyes that had vitrectomy is comparable to that reported in the literature for routine pediatric cataract surgeries. Factors such as age, axial length, corneal power, IOL position (bag/sulcus), scleral buckle, corneal suture, and silicone oil removal done prior to surgery or along with cataract surgery did not affect the APE. [J Pediatr Ophthalmol Strabismus. 2021;58(2):126-131.].

CuInS/ZnS quantum dots modified intraocular lens for photothermal therapy of posterior capsule opacification

Posterior capsule opacification (PCO) after cataract surgery is one of the leading causes of visual impairment and blindness. The cause of PCO is the capsule fibrosis developed on implanted Intraocular Lens (IOLs) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing epithelial mesenchymal transition. How to prevent PCO has been a challenge to scientists and ophthalmologists for decades. Here we demonstrated the use of carboxylated CuInS/ZnS quantum dots (ZCIS QDs), which are free of toxic heavy metals and are more biocompatible, as photothermal nanomedicines. The ZCIS QDs are modified onto the non-optical section of IOLs by a facial activation-immersion method. Under mild NIR laser irradiation, ZCIS QDs modified IOLs (QDs-IOLs) will generate localized heat and prevent the proliferation of LECs onto the surface of QDs-IOLs. Our findings provide experimental evidence for further application of combined nanotechnology and photothermal therapy for the clinical treatment of PCO.

Characterization of postoperative "fibrin web" formation after canine cataract surgery

PURPOSE

To describe the occurrence and associated factors for "fibrin web" (FW) formation following phacoemulsification in dogs.

METHODS

A retrospective review of medical records of all dogs undergoing phacoemulsification (MU-Veterinary Health Center, 2014-2018) was conducted to associate FW formation with signalment, systemic co-morbidities, cataract stage, surgeon (resident vs faculty), phacoemulsification time, IOL, and intracameral injections including viscoelastic type. Both univariate and multivariate statistical analyses were performed to evaluate associations among variables with FW formation.

RESULTS

Data from 398 eyes on 201 dogs were included; 4 left eyes (4 dogs) developed presumptive endophthalmitis and were excluded from further analysis. Forty-eight eyes did not have cataract surgery. Hence, 350 eyes on 201 dogs were included in the analyses. Among these, 84 eyes (59 dogs) developed a FW. Univariate analyses showed that the odds of FW increased with age and phacoemulsification time. Additionally, FW web was associated lens type, lens brand, and viscoelastic type. Multivariate analyses showed that when comparing lens types in combination with a particular viscoelastic, viscoelastic impacted the estimated prevalence of FW formation the most. In contrast, when the data were analyzed by lens brand, lens brand impacted prevalence more than viscoelastic type. Diabetes mellitus was not associated with FW formation.

CONCLUSIONS

Based on the available data, intraocular lens implantation, viscoelastic type, dog age, and phacoemulsification time were associated with FW formation. Diabetes mellitus, gender, cataract stage, surgeon, intracameral injections other than viscoeleastic, and intra- and postoperative complications were not associated with FW formation.

Outcomes of Bilateral Cataracts Removed in Infants 1 to 7 Months of Age Using the Toddler Aphakia and Pseudophakia Treatment Study Registry

PURPOSE

To evaluate outcomes of bilateral cataract surgery in infants 1 to 7 months of age performed by Infant Aphakia Treatment Study (IATS) investigators during IATS recruitment and to compare them with IATS unilateral outcomes.

DESIGN

Retrospective case series review at 10 IATS sites.

PARTICIPANTS

The Toddler Aphakia and Pseudophakia Study (TAPS) is a registry of children treated by surgeons who participated in the IATS.

METHODS

Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement during IATS enrollment years 2004 through 2010.

MAIN OUTCOME MEASURES

Visual acuity (VA), strabismus, adverse events (AEs), and reoperations.

RESULTS

One hundred seventy-eight eyes (96 children) were identified with a median age of 2.5 months (range, 1-7 months) at the time of cataract surgery. Forty-two eyes (24%) received primary IOL implantation. Median VA of the better-seeing eye at final study visit closest to 5 years of age with optotype VA testing was 0.35 logarithm of the minimum angle of resolution (logMAR; optotype equivalent, 20/45; range, 0.00-1.18 logMAR) in both aphakic and pseudophakic children. Corrected VA was excellent (<20/40) in 29% of better-seeing eyes, 15% of worse-seeing eyes. One percent showed poor acuity (≥20/200) in the better-seeing eye, 12% in the worse-seeing eye. Younger age at surgery and smaller (<9.5 mm) corneal diameter at surgery conferred an increased risk for glaucoma or glaucoma suspect designation (younger age: odds ratio [OR], 1.44; P = 0.037; and smaller cornea: OR, 3.95; P = 0.045). Adverse events also were associated with these 2 variables on multivariate analysis (younger age: OR, 1.36; P = 0.023; and smaller cornea: OR, 4.78; P = 0.057). Visual axis opacification was more common in pseudophakic (32%) than aphakic (8%) eyes (P = 0.009). Unplanned intraocular reoperation occurred in 28% of first enrolled eyes (including glaucoma surgery in 10%).

CONCLUSIONS

Visual acuity after bilateral cataract surgery in infants younger than 7 months is good, despite frequent systemic and ocular comorbidities. Although aphakia management did not affect VA outcome or AE incidence, IOL placement increased the risk of visual axis opacification. Adverse events and glaucoma correlated with a younger age at surgery and glaucoma correlated with the presence of microcornea.

Long-Term Outcome of Nd:YAG Laser Posterior Capsulotomy in Children: Procedural Strategies and Visual Outcome

PURPOSE

To evaluate the long-term outcome of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy after cataract surgery in children.

DESIGN

Retrospective case series.

METHODS

Electronic medical records of pediatric patients who underwent Nd:YAG laser posterior capsulotomy between January 1, 2008, and October 31, 2012, and followed up for more than 5 years were reviewed.

RESULTS

Thirty-one eyes of 25 patients were included. Only compliant patients assessed during slit-lamp examination and anterior segment photography underwent laser treatment. The mean age at the time of initial laser treatment was 9.04 ± 3.51 years (minimum 56 months), and the mean interval between cataract surgery and initial laser treatment was 28.1 ± 22.1 months. Posterior capsular openings were successfully made in 26 (83.9%) eyes with a single attempt and in 3 (9.7%) eyes with a second attempt. Overall success rate was 93.5%. The logMAR best-corrected visual acuity was significantly improved from 0.61 ± 0.36 to 0.19 ± 0.25 at 1 month posttreatment (P < .0001) and well maintained, at least for 5 years of follow-up, without serious complications. The recurrence of posterior capsular opacity was observed in 7 (24.1%) eyes, which was successfully managed by repeated laser procedure or surgical capsulectomy.

CONCLUSIONS

By selecting compliant patients and repeated attempts, Nd:YAG laser posterior capsulotomy can be successfully performed in a pediatric population without serious complications. Laser treatment is also a good option for managing recurred posterior capsular opacity. Restored visual acuity can be maintained for at least 5 years.

Predicting Factor of Visual Outcome in Unilateral Idiopathic Cataract Surgery in Patients Aged 3 to 10 Years

Purpose

To report the surgical results of unilateral pediatric cataracts from uncertain causes in relatively older children and to identify factors related to better visual outcomes.

Methods

We retrospectively evaluated the medical records of 39 patients who underwent surgery between the ages of 3 and 10 years for unilateral pediatric cataracts of no known cause. All patients underwent primary intraocular lens implantation and postoperative amblyopia treatment. A postoperative final visual acuity better than 20 / 30 was considered to be a good visual outcome.

Results

The mean age of patients was 6.0 ± 1.8 years at the time of surgery. The mean preoperative visual acuity was 1.07 ± 0.71 logarithm of the minimum angle of resolution (range, 0.15 to 3.00), while the mean final postoperative visual acuity was 0.47 ± 0.54 logarithm of the minimum angle of resolution (range, 0.00 to 2.00). Of 39 patients, 18 (46.2%) achieved a good visual outcome. Only the preoperative visual acuity maintained a significant association with a good visual outcome according to our multivariate analysis (p = 0.040). A preoperative visual acuity of 20 / 100 or better was found to increase the chance of achieving a good visual outcome by 13.79-fold (95% confidence interval, 1.13 to 167.58).

Conclusions

The visual outcome of unilateral pediatric cataract surgery for cataracts with no specific cause identified in patients after three years of age could be satisfactory, especially with a preoperative visual acuity of 20 / 100 or better.

Long-term Outcomes of Primary Intraocular Lens Implantation in Patients Aged 7 to 24 Months

PURPOSE

To report long-term outcomes of primary intraocular lens (IOL) placement in patients aged 7 to 24 months.

METHODS

This was a retrospective study of 27 consecutive patients (28 eyes) aged 7 to 24 months who underwent cataract surgery with primary IOL placement.

RESULTS

Average follow-up was 62.7 ± 41.7 months and the mean age of surgery was 14.4 ± 5.6 months. Mean final visual acuity was 1.02 ± 0.72 logMAR (20/209). Adverse events occurred in 7 eyes (25%) and included visual axis opacification in 6 eyes and pupillary block glaucoma in 1 eye. Seven patients (25.9%) required additional intraocular surgery. Strabismus was present in 19 patients (70.4%). Better stereopsis was correlated with better final acuity.

CONCLUSIONS

Cataract surgery with IOL placement in patients aged 7 to 24 months is associated with few complications. Visual axis opacification is the most frequent adverse event. [J Pediatr Ophthalmol Strabismus. 2017;54(3):149-155.].

Long-term outcomes of ciliary sulcus versus capsular bag fixation of intraocular lenses in children: An ultrasound biomicroscopy study

Purpose

To evaluate the long-term outcomes of ciliary sulcus versus capsular bag fixation of intraocular lenses (IOLs) in children after pediatric cataract surgery.

Methods

IOL was implanted in the ciliary sulcus in 21 eyes of 14 children, and in the capsular bag in 19 eyes of 12 children for the treatment of pediatric cataract in an institutional setting. Ultrasound biomicroscopy (UBM) was performed. Main outcome measures included IOL decentration, IOL tilt, anterior chamber depth (ACD), angle-opening distance at 500 μm (AOD₅₀₀), trabecular-iris angle (TIA), best-corrected visual acuity (BCVA), intraocular pressure (IOP), and incidence of postoperative complications.

Results

The mean follow-up period was 6.81 ± 1.82 years. Comparing to the capsular bag fixation group, the ciliary sulcus fixation group had higher vertical IOL decentration, horizontal IOL tilt, and vertical IOL tilt (p = 0.02, 0.01,0.01, respectively), higher incidence of iris-IOL contact and peripheral anterior synechia (p = 0.001, 0.03, respectively), smaller ACD, AOD₅₀₀, and TIA (p = 0.02, 0.03, 0.04, respectively), higher mean IOP (17.10 ±6.06 mmHg vs.14.15± 4.74 mmHg, p = 0.01), and higher incidence of secondary glaucoma (28.57% vs. 10.53%, p = 0.007).There was no significant difference between the two groups with regard to the BCVA, refractive errors, incidence of myopic shift, nystagmus, strabismus, and visual axis opacity.

Conclusions

Ciliary sulcus fixation of IOLs in pediatric eyes may increase IOL malposition and crowding of the anterior segment, and may associate with a higher risk of secondary glaucoma compared to capsular bag fixation of IOLs.

Two kinds of ocular trauma score for paediatric traumatic cataract in penetrating eye injuries

PURPOSE

To compare the ocular trauma score (OTS) and the paediatric penetrating ocular trauma score (POTS) as prognostic model for visual outcome in paediatric traumatic cataract cases after penetrating eye injuries.

METHODS

All children younger than 16 years with unilateral traumatic cataract following penetrating trauma between 2007 and 2012 were retrospectively reviewed. Univariate chi-square analysis was conducted to identify the variables associated with profound visual loss. The area under the receiver-operating characteristic curves (AUROC) was used to assess the predictive ability of the two models.

RESULTS

The study group comprised 65 boys and 37 girls. The variables associated with profound visual loss were: a relative afferent papillary defect (RAPD) (P<0.001), poor initial vision (P=0.01), vitreous haemorrhage (P<0.001), retinal detachment (P<0.001), posterior penetrating site (P<0.001), hyphema (P<0.001), no intraocular len implantation (P<0.001) and endophthalmitis (P=0.001). OTS could not be calculated in 21 patients (20.6%) without clinical data on initial visual acuity and RAPD. For the patients with complete clinical data, POTS was similar to OTS in predicting poor vision (AUROC 0.904 vs 0.924) and in predicting good vision (AUROC 0.766 vs 0.736). For all the samples, POTS was a robust predictor of poor vision (AUROC 0.910) and had a moderate ability to predict good vision (AUROC 0.764).

CONCLUSION

OTS has high ability to predict visual outcome for paediatric traumatic cataract following penetrating ocular trauma. POTS is also a reliable prognostic model for very young child without initial vision or RAPD, but is only for penetrating eye injuries.

Pediatric infectious endophthalmitis: a review

Infectious endophthalmitis is a rare but severe complication of septecemia, intraocular surgeries, or penetrating eye trauma. The etiology, prognosis, and management of pediatric endophthalmitis resulting from exogenous and endogenous infections are reviewed. Open-globe trauma and glaucoma surgery are the most frequent causes of endophthalmitis in children, whereas endogenous infection is the least common cause. Streptococcus and Staphylococcus species are common bacterial agents in both posttraumatic and postoperative pediatric endophthalmitis, whereas Candida albicans is a commonly reported organism in endogenous endophthalmitis. Additionally, Streptococcus pneumoniae and Haemophilus influenzae appear more likely as pathogens in children than in adults. The clinical manifestations and outcome usually correlate with the virulence of the infecting organism. The visual prognosis of endophthalmitis is generally poor.

Comparison of hospital versus rural eye cAMP based pediatric cataract surgery

Purpose:

To compare the outcomes of pediatric cataract surgery with intraocular lens (IOL) implantation in an eye camp setting and tertiary care center.

Materials and Methods:

Children aged 5-16 years with visually significant cataract underwent phacoaspiration with IOL implantation in an eye camp (eye camp group) or tertiary care center (TCC group). All surgeries incorporated contemporary microsurgical techniques with implantation of polymethyl-methacrylate (PMMA) IOL. Major postoperative complications were managed at a tertiary care center. Postoperative complications, visual acuity and compliance were evaluated using the Chi-square test. A P value less then 0.05 was considered as statistically significant.

Results:

The cohort comprised 59 children in the eye camp group and 48 children in the TCC group. Thirty two of fifty nine (54.23%) eyes in the eye camp group and 30/48 (62.5%) eyes in the TCC group achieved 20/40 or better best corrected visual acuity (BCVA) postoperatively. Postoperatively, 36 (61%) eyes in the eye camp group and 22 (45.83%) eyes in the TCC group required Nd: YAG laser capsulotomy or a pars plana membranectomy. (P> 0.05) The most striking feature was loss to follow up. In the eye camp group, loss to follow was 20% at one year, 49% at two years, 62% at 3 years and 67% at 4 years compared to 12.5, 21, 27 and 33% respectively in the TCC group (P<0.05, all cases).

Conclusions:

The outcomes of camp and tertiary care center (hospital) based pediatric cataract surgery were similar. However, the major drawback of camp based surgery was loss to follow up which eventually affected the management of amblyopia and postoperative complications.

Long-term Outcomes of Undercorrection Versus Full Correction After Unilateral Intraocular Lens Implantation in Children

PURPOSE

To evaluate the impact of full correction vs undercorrection on the magnitude of the myopic shift and postoperative visual acuity after unilateral intraocular lens (IOL) implantation in children.

DESIGN

Retrospective case control study.

METHODS

The medical records of 24 children who underwent unilateral cataract surgery and IOL implantation at 2 to <6 years of age were reviewed. The patients were divided into 2 groups based on their 1-month-postoperative refraction: Group 1 (full correction) -1.0 to +1.0 diopter (D) and Group 2 (undercorrection) ≥+2.0 D. The main outcome measures included the change in refractive error per year and visual acuity for the pseudophakic eyes at last follow-up visit. The groups were compared using the independent groups t test and Wilcoxon rank sum test.

RESULTS

The mean age at surgery (Group 1, 4.2±0.9 years, n=12; Group 2, 4.5±1.0 years, n=12; P=.45) and mean follow-up (Group 1, 5.8±3.7 years; Group 2, 6.1±3.5 years; P=.69) were similar for the 2 groups. The change in refractive error (Group 1, -0.4±0.5 D/y; Group 2, -0.3±0.2 D/y; P=.70) and last median logMAR acuity (Group 1, 0.4; Group 2, 0.4; P=.54) were not significantly different between the 2 groups.

CONCLUSIONS

We did not find a significant difference in the myopic shift or the postoperative visual acuity in children aged 2 to <6 years of age following unilateral cataract surgery and IOL implantation if the initial postoperative refractive error was near emmetropia or undercorrected by 2 diopters or more.

Long-term outcome of primary versus secondary intraocular lens implantation after simultaneous removal of bilateral congenital cataract

BACKGROUND

Long-term outcomes of intraocular lens (IOL) implantation for congenital cataract in children under 2 years old are still undetermined.

METHODS

We retrospectively reviewed all cases of bilateral congenital cataract who had undergone simultaneous bilateral cataract removal with posterior capsulotomy and central anterior vitrectomy between 1990 and 2010. Patients randomly underwent primary IOL implantation or secondary IOL implantation after a period of contact lens wear. The two groups were compared for visual outcome and complications during follow-up.

RESULTS

Cataract removal and primary IOL implantation was performed in 30 eyes (15 patients; nine males, six females) at a mean age of 6.8 ± 4.2 months. After 79.31 ± 63.4 months, best-corrected visual acuity (BCVA) was 0.53 ± 0.36 EDTRS LogMAR. In 36 eyes (18 patients, 11 males, seven females) the lens was removed at a mean age of 5.42 ± 2.80 months, and after 32.0 ± 6.1 months of contact lens utilization, secondary IOL implantation was performed. After 109.0 ± 33.8 months, BCVA was 0.54 ± 0.4 ETDRS LogMAR. The association between age at surgery and final visual acuity and the difference between the two groups concerning type of cataract at baseline, BCVA and refractive error at last visit, incidence of posterior capsular opacification, glaucoma, strabismus, and nystagmus during follow-up were not significant (p > 0.05). Myopic shift was more frequent in eyes undergone primary IOL implantation (p < 0.001).

CONCLUSIONS

Similar visual outcome and complications were observed during long-term follow-up after both primary and secondary IOL implantation following simultaneous bilateral congenital cataract removal with posterior capsulotomy and central anterior vitrectomy.

Prediction error and accuracy of intraocular lens power calculation in pediatric patient comparing SRK II and Pediatric IOL Calculator

Background

Despite growing number of intraocular lens power calculation formulas, there is no evidence that these formulas have good predictive accuracy in pediatric, whose eyes are still undergoing rapid growth and refractive changes. This study is intended to compare the prediction error and the accuracy of predictability of intraocular lens power calculation in pediatric patients at 3 month post cataract surgery with primary implantation of an intraocular lens using SRK II versus Pediatric IOL Calculator for pediatric intraocular lens calculation. Pediatric IOL Calculator is a modification of SRK II using Holladay algorithm. This program attempts to predict the refraction of a pseudophakic child as he grows, using a Holladay algorithm model. This model is based on refraction measurements of pediatric aphakic eyes. Pediatric IOL Calculator uses computer software for intraocular lens calculation.

Methods

This comparative study consists of 31 eyes (24 patients) that successfully underwent cataract surgery and intraocular lens implantations. All patients were 12 years old and below (range: 4 months to 12 years old). Patients were randomized into 2 groups; SRK II group and Pediatric IOL Calculator group using envelope technique sampling procedure. Intraocular lens power calculations were made using either SRK II or Pediatric IOL Calculator for pediatric intraocular lens calculation based on the printed technique selected for every patient. Thirteen patients were assigned for SRK II group and another 11 patients for Pediatric IOL Calculator group. For SRK II group, the predicted postoperative refraction is based on the patient's axial length and is aimed for emmetropic at the time of surgery. However for Pediatric IOL Calculator group, the predicted postoperative refraction is aimed for emmetropic spherical equivalent at age 2 years old. The postoperative refractive outcome was taken as the spherical equivalent of the refraction at 3 month postoperative follow-up. The data were analysed to compare the mean prediction error and the accuracy of predictability of intraocular lens power calculation between SRK II and Pediatric IOL Calculator.

Results

There were 16 eyes in SRK II group and 15 eyes in Pediatric IOL Calculator group. The mean prediction error in the SRK II group was 1.03 D (SD, 0.69 D) while in Pediatric IOL Calculator group was 1.14 D (SD, 1.19 D). The SRK II group showed lower prediction error of 0.11 D compared to Pediatric IOL Calculator group, but this was not statistically significant (p = 0.74). There were 3 eyes (18.75%) in SRK II group achieved acccurate predictability where the refraction postoperatively was within ± 0.5 D from predicted refraction compared to 7 eyes (46.67%) in the Pediatric IOL Calculator group. However the difference of the accuracy of predictability of postoperative refraction between the two formulas was also not statistically significant (p = 0.097).

Conclusions

The prediction error and the accuracy of predictability of postoperative refraction in pediatric cataract surgery are comparable between SRK II and Pediatric IOL Calculator. The existence of the Pediatric IOL Calculator provides an alternative to the ophthalmologist for intraocular lens calculation in pediatric patients. Relatively small sample size and unequal distribution of patients especially the younger children (less than 3 years) with a short time follow-up (3 months), considering spherical equivalent only.

Refractive outcomes with secondary intraocular lens implantation in children

PURPOSE

To determine the accuracy of postoperative predicted refractive outcomes in surgically aphakic pediatric patients undergoing secondary intraocular lens (IOL) implantation. Comparisons were also made with other variables historically considered important in cataract surgery.

METHODS

Retrospective review of 50 eyes from 35 consecutive pediatric patients (< or =18 years of age) undergoing secondary IOL implantation within the ciliary sulcus or posterior capsular bag. All cases were performed by 1 of 2 surgeons and all refractions were performed manually using the retinoscope by an experienced pediatric ophthalmologist.

RESULTS

The mean patient age at the time of the secondary implantation was 6.5 years of age (range, 0.58-15.04). The mean patient age at the time of the primary cataract extraction was 0.78 years (range, 0.08-5.77). For all patients, mean absolute value of prediction error was 1.64 D (SD 1.58 D). There were no significant associations between mean absolute value of prediction error and any of the variables measured including axial length, corneal mean curvature, bag or sulcus implantation, formula used, or age at primary and secondary surgery (p > 0.05).

CONCLUSIONS

The mean absolute value of prediction error observed in this study is consistent with previous pediatric primary and secondary IOL data in that it shows a considerable difference from that expected in adult populations. Our findings support the argument that methods currently employed to calculate IOL power may fail to accurately account for all the variations in the eyes of pediatric patients.

Congenital cataract extraction with primary aphakia and secondary intraocular lens implantation in the posterior chamber

PURPOSE

To evaluate visual outcomes, eye movement abnormalities, and postoperative complications after secondary posterior chamber intraocular lens (IOL) implantation in aphakic children who had initial LAC correction.

METHODS

A retrospective study was carried out on 53 patients (94 eyes). Following aphakic surgery and LAC correction the patients received secondary IOL implantation in the posterior chamber. Special attention was paid to factors that may have influenced their visual outcomes, such as eye movement abnormalities, cataract unilaterality, and cataract density.

RESULTS

No association was found between age at surgery and the onset of strabismus (p=0.611) or with visual acuity (p=0.086). However, unilaterality and total cataract density were found to have a negative association with poor vision (p<0.001). Strabismus and nystagmus were found to have a statistically significant negative association with visual acuity (p=0.002). Posterior capsule opacification occurred in six eyes of five patients following cataract extraction; IOL dislocation occurred in four eyes after IOL intraocular implantation, and secondary glaucoma occurred in one eye.

CONCLUSIONS

IOL implantation before 12 months of age may be useful in unilateral cataract; in bilateral cataract, simultaneous surgical aphakia, LAC correction, and then IOL implantation at 2.5-3 years of age, together with anti-amblyopic therapy when strabismus or asymmetric cataract density occur, are efficient methods to obtain visual recovery. Extraocular muscle surgery may be required to correct strabismus.

Accuracy of IOL calculations in children: a comparison of immersion versus contact A-scan biometery

PURPOSE

To evaluate the accuracy of pediatric IOL calculations performed under general anesthesia by using immersion A-scan biometry and to compare the results to those obtained using contact A-scan biometry.

METHODS

A retrospective review of 203 consecutive cases of pediatric cataract extraction with primary IOL implantation within the capsular bag; mean patient age was 5.52 +/- 4.19 years (range, 18 days to 18 years). Axial length measurements were performed with the contact A-scan biometry in 138 eyes, whereas immersion technique biometry was used in the remaining consecutive 65 eyes. Preoperative predictive target refraction was compared with the refractive result obtained at the 2-month postoperative visit.

RESULTS

The mean of the absolute value lens prediction error for all eyes was 1.08 +/- 0.93 D from the desired postoperative refractive result. Lens prediction error for the contact A-scan subgroup was 1.11 +/- 0.90 D, whereas the immersion A-scan subgroup was less at 1.03 +/- 0.98 D. This result was not statistically significant (p = 0.6442). Statistically significant correlations were found between increased lens prediction error and age at time of surgery or corneal curvature.

CONCLUSIONS

This retrospective, noncomparative pilot study showed no significant difference in IOL prediction error when comparing the postoperative refractive results obtained with immersion versus contact A-scan biometry in pediatric IOL calculations.

Postcataract surgery outcome in a series of infants and children with Down syndrome

AIMS

To report the visual and refractive outcome and complications in children with Down syndrome undergoing cataract extraction.

METHODS

The case notes of 18 infants and children with lens opacities and Down syndrome who underwent cataract extraction between January 1981 and August 2006 were reviewed.

RESULTS

Over the 25-year study period, 7% (33 eyes) of paediatric eyes undergoing cataract extraction had Down syndrome. The average follow-up time was 11.2 (SD 7.5) years with a range of 2.5 months to 25 years. 25 were congenital, and eight were developmental lens opacities. 40% of patients attained a postoperative BCVA between 6/9 and 6/18. There was a large myopic shift of -7.96 (4.7) D for aphakes and -8.06 (7.4) D for pseudophakes with an average increase in axial length of 3.58 (3.14) mm. There was a 30% incidence of posterior capsular opacification (PCO) overall, 38% in eyes without a primary posterior capsulotomy. Five eyes developed aphakic glaucoma, one eventually necessitating an enucleation. Two patients had retinal detachments on follow-up.

CONCLUSION

Cataract extraction in our population of children with Down syndrome is a safe and effective procedure with a very encouraging visual outcome.

Bilateral paediatric cataract surgery in the same session

PURPOSE

To evaluate the results of bilateral paediatric cataract surgery in the same session with a focus on patient selection criteria, operative guidelines, and controversial issues.

SETTING

Departments of Ophthalmology, Inönü University Turgut Ozal Medical Center (Malatya) and Fatih University Hospital (Ankara, Turkey).

METHODS

This retrospective noncomparative case series comprised 39 children (78 eyes), who underwent bilateral cataract surgery and/or primary or secondary IOL implantation in one sitting. Ten patients had bilateral lensectomy-primary posterior capsulotomy-anterior vitrectomy, and the remaining 29 patients had bilateral IOL implantation either primarily (20 cases) at the time of cataract extraction or secondarily for aphakic correction (9 cases). Both eyes were treated as two separate but consecutive surgeries in the same session. Maximum possible care was taken to ensure surgical asepsis.

RESULTS

Age at surgery ranged from 2 months to 17 years. Average follow-up was 12 months. No serious intraoperative or postoperative complications occurred leading to permanent vision loss. During the last follow-up, 91% of eyes tested had a visual acuity of 20/40 or better.

CONCLUSION

Bilateral paediatric cataract surgery in one session may be a safe and useful approach alternative to sequential surgery in selected patients, if operative guidelines and surgical asepsis are strictly followed.

Intraocular lens power calculation in children

With improving surgical technique and equipment, the acceptable age for placing an intraocular lens in infants and children is becoming younger. The tools for predicting intraocular lens power have not necessarily kept up, as current theoretical and regression intraocular lens power prediction formulas are largely based on adult eyes at axial lengths, anterior chamber depth, and keratometric values much different than those seen in infants. In addition, the adult eye has matured and is no longer growing, whereas the eyes of infants and children may continue to note changes in axial length, keratometric values, and possibly optical characteristics. Another source of error in intraocular lens power selection that is more likely to occur in pediatric patients than in adult patients is inaccuracy in measurement of axial length or keratometric power. A review of current tools and considerations for intraocular lens power prediction in infants and children is presented.

Long-term refractive change after intraocular lens implantation in childhood

BACKGROUND

To determine refractive change occurring with age in children who had cataract removal with intraocular lens implantation and in whom the immediate postoperative refraction was targeted either to match the refractive error of the opposite eye in unilateral cases, or for only a small refractive error when surgery was bilateral.

METHODS

Retrospective review of the refractive error over time in 36 eyes of 25 children who underwent cataract removal (11 bilateral) with insertion of an intraocular lens from 1987 to 1998 and who had at least 4 years follow-up, but no glaucoma.

RESULTS

Mean age at surgery was 5.5 years (median 5.7 y, range 1.3-12 y), with a mean follow-up of 8 years (median 6 y, range 4-16 y). The average refraction followed a logarithmic decline with age. Although eyes with unilateral surgery had a slightly faster rate of change and lower final refraction than did eyes with bilateral surgery, this difference was not statistically significant. Variation from this trend was also observed in 3 patients. When the hyperopic refractive error created immediately after surgery was small, children usually became significantly myopic when older, often creating anisometropic myopia in unilateral cases.

INTERPRETATION

When implanting intraocular lenses bilaterally one should aim for a significant but balanced hyperopic correction immediately postoperatively in young patients, anticipating that there will be emmetropization with aging. Parents should be warned that variations can occur.

Combined cataract and strabismus surgery with adjustable sutures

BACKGROUND AND OBJECTIVE

To report the results of combined cataract and strabismus surgery using an adjustable suture technique in patients of different ages.

PATIENTS AND METHODS

Twenty patients underwent combination surgery between March 1999 and January 2004. All adjustments of the muscle sutures were done 24 hours postoperatively to prevent diplopia, and topical anesthesia was used for all but 1 patient. Bilateral lateral rectus recession was performed for 5 patients; medial rectus resection and lateral rectus recession was performed for 11 patients, and medial rectus recession and lateral rectus resection was performed for 4 patients. Extracapsular cataract extraction and phacoemulsification plus intraocular lens implantation was done according to the type of cataract.

RESULTS

Preoperative visual acuities ranged between 20/8000 and 20/400. Eighteen of the patients had a cataract and 2 of the patients had aphakia due to previous cataract surgery. Considerable improvement in vision was obtained in 10 patients, and a postoperative visual acuity of 20/25 was achieved in 1 patient. Deviations improved from between 30 and 45 prism diopters preoperatively to between 2 and 8 prism diopters postoperatively.

CONCLUSION

Combined cataract and strabismus surgery with adjustable sutures can be an alternative to the conventional method. It is less time-consuming for both the patient and the surgeon, and provides faster cosmetic and functional rehabilitation in a single operation.

Two-photon absorption-controlled multidose drug release: a novel approach for secondary cataract treatment

Tens of millions of cataract surgeries are done every year and the number is increasing heavily. Posterior capsule opacification is the major postoperative complication with an incidence of 10 to 50% within 5 years, depending on the age of the patient. We present a novel approach for secondary cataract treatment in a noninvasive manner. Photochemically triggered drug release from a polymer enables repeated drug applications for cataract treatment years after implantation of the intraocular lens, just when needed. However, light in the visible spectral range must pass through the lens but must not induce drug release. We demonstrate that two-photon absorption photochemistry is a powerful tool to overcome this problem. With wavelengths in the visible regime, a photochemical reaction that requires energies in the UV is triggered. The high intensities needed for this process never occur in any lighting condition in daily lives, but may be easily obtained with focused laser beams routinely used in ophthalmology. The properties of the therapeutic system are specified and the function is demonstrated by in-vitro cell tests. Noninvasive multidose photochemically triggered drug release from implanted intraocular lenses carrying a drug depot may be a therapeutic as well as an economic choice to established treatments of secondary cataracts.

Long term results of primary posterior chamber intraocular lens implantation for congenital cataract in the first year of life

AIM

To document the long term outcome of congenital cataract surgery with primary posterior chamber (PC) lens implantation in the first year of life.

METHOD

A retrospective review of congenital cataract surgery in the first year of life with PC lens implantation in 18 infants, eight with unilateral and 10 with bilateral cataract. The average age at surgery was 15 weeks (range 3-44 weeks). The mean follow up was 95 months (range 60-139 months).

RESULTS

The best outcomes were in the bilateral group where 50% of eyes achieved 6/18 or better, with a best acuity of 6/9. Acuities were poor in the unilateral group where only 38% achieved 6/60 or better, with a best acuity of 6/24. There was a mean refractive shift between first refraction after surgery and refraction at 36 months after surgery of -3.44 dioptres with a very wide range (+2.00 to -15.50). There was a significantly greater myopic shift in the unilateral cases. Many eyes in both groups continued to show an increasing myopic shift between 36 months after surgery and their final recorded refraction. The main complications were amblyopia, especially in unilateral cataracts, and posterior capsular opacification. Amblyopia was most probably related to a combination of early onset of dense cataract in this young age group, late presentation for initial surgery, delay in capsulotomies, and imperfect compliance with a rigorous occlusion regime.

CONCLUSION

Intraocular lens implantation in infants less than 1 year of age is generally a safe procedure. The spread of final refractive error was very wide. Final refraction in the unilateral group was significantly more myopic than the bilateral group. Final acuities were often disappointing especially in the unilateral group.

Incidence and risk factors for glaucoma after pediatric cataract surgery with and without intraocular lens implantation

PURPOSE

We sought to report the incidence of glaucoma in the eyes of children who underwent cataract surgery with and without intraocular lens implantation and to report the risk factors for developing glaucoma.

METHODS

We undertook a retrospective review of pediatric cataract surgery charts, excluding traumatic cataract, aniridia and Lowe syndrome, steroid-induced cataract, lens subluxation, uveitis, retinoblastoma, radiation-induced cataract, retinopathy of prematurity, secondary IOL implantation, and patients with less than 1 month of postoperative follow-up.

RESULTS

After pediatric cataract surgery, 10 (3.8%) of 266 eyes with primary intraocular lens implantation were diagnosed with glaucoma, whereas 8 (17.0%) of 47 aphakic eyes were diagnosed with glaucoma. During the initial analyses, we noted that all of the patients who developed glaucoma underwent cataract surgery when they were 4.5 months or younger. For all patients who underwent surgery during the first 4.5 months of their life, the glaucoma incidence was 24.4% (10/41) in children with pseudophakic eyes and 19.0% (8/42) in age-matched children with aphakic eyes (risk ratio=1.1, CI=0.7-1.9; P=.555). In patients who underwent surgery during the first 4.5 months of their life, the average age of the patients who developed glaucoma was not significantly different than those who did not develop glaucoma in pseudophakic eyes (2.0 months+/-1.4 vs. 1.9 months+/-1.0, P=.700) or aphakic eyes (2.6 months+/-1.5 vs. 1.4 months+/-0.9, P=.070). The corneal diameter of the eyes that developed glaucoma versus eyes that did not was not significantly different in patients with pseudophakic eyes (P=.860) or aphakic eyes (P=.254). Glaucoma was diagnosed in patients at an average of 8.6 months and 117.9 months after cataract surgery in those with pseudophakic eyes and aphakic eyes, respectively.

CONCLUSIONS

Patients undergoing cataract surgery at an early age are at high risk for the development of glaucoma with or without an intraocular lens implant.

Techniques of intraocular lens suspension in the absence of capsular/zonular support

Implantation of intraocular lenses has become the standard of care in the aphakic state. Ideally, the lens is placed in the capsular bag, which affords stable fixation at a position closest to the nodal point of the eye. However, there will always be instances where this will not be possible. Congenital weakness of the lens zonules in various conditions, trauma, and surgical complications of cataract surgery are just some examples. In this article, we review the methods that have been devised to allow intraocular lens implantation in the absence of capsular or zonular support. These include anterior chamber angle and iris-fixated lenses, as well as posterior chamber iris- and scleral-sutured lenses. The various lenses are described, and the techniques involved, advantages and disadvantages, complications, and results of each method are discussed. It is hoped that this article will provide a comprehensive overview of ways to deal with a problem that can still result in a very good visual outcome for the patient. This is particularly relevant given the many recent developments and refinements of methods in implanting intraocular lenses.

Cataract extraction and primary hydrophobic acrylic intraocular lens implantation in infants

PURPOSE

We sought to report the incidence of visual axis opacification and to evaluate the complication and reoperation rates after intraocular lens implantation in infants.

METHODS

Twenty-one infants (31 eyes) who had cataract extraction with primary hydrophobic acrylic IOL implantation between October 1996 and May 2002 were reviewed. Posterior capsule was left intact in 14 eyes (group A); posterior capsulorrhexis or capsulotomy with anterior vitrectomy was performed in 17 eyes (group B). Complication and reoperation rates were compared with an age-matched control group of 17 patients (33 eyes) who were left aphakic after pars plicata lensectomy. Mean follow-up period was 41 months (range, 22-75 months) in group A, 37 months (range, 10-75 months) in group B, and 52 months (range, 7-97 months) in the control group.

RESULTS

Mean age of the patients was 6.8 months (range, 3-10 months) in group A, 8.9 months (range, 3-18 months) in group B, and 4.9 months (range, 1-15 months) in the control group. Visual axis opacification was significantly higher in group A (86%) when compared with group B (17.6%; P < 0.0001). No significant difference was found in terms of pupillary irregularities and peripheral anterior synechiae formation between pseudophakic and aphakic group ( P = 0.43 and P = 0.306, respectively), whereas pigment dispersion and fibrinous reaction were significantly more common in the pseudophakic group ( P = 0.002). Serious complications, such as retinal detachment, pseudophakic bullous keratopathy, and secondary glaucoma, did not develop in any eye. Reoperation rate was significantly higher in group A (78%) when compared with group B (17%) and the control group (12%; P = 0.0011 and P < 0.0001, respectively).

CONCLUSIONS

Visual axis opacification requiring a reoperation was significantly more common in patients with an intact posterior capsule. To decrease the reoperation rate and maintain a clear visual axis, posterior capsulorrhexis with anterior vitrectomy should be performed. Even although early complications were quite frequent, serious late complications were not encountered in any eye. Therefore, under appropriate conditions, IOL implantation is a suitable alternative in infants.

Visual results after primary intraocular lens implantation or contact lens correction for aphakia in the first year of age

PURPOSE

The optimal role of intraocular lenses (IOLs) in infants remains a controversial topic. Some ophthalmologists advocate correction with a contact lens (CL), whereas others recommend an IOL correction. Our study compared visual acuity, ocular alignment, retreatment rate and binocular vision outcomes in children treated with these two methods at our clinic.

METHODS

This study included 41 children with unilateral congenital cataract who underwent cataract surgery with posterior capsulorhexis and anterior vitrectomy, coupled with (IOL group, n=18) or without (CL group, n=23) primary IOL implantation. All infants underwent the first surgery during the first 12 months of their life and they were operated on in the period from 1994 to 1999. The mean age at surgery was 3.11+/-2.65 months (range: 28 days to 11 months). All patients were prescribed the same half-time reduced occlusion therapy. Good cooperation of the parents and good compliance with patching were the necessary conditions to include a patient in the study. Between January and February 2003, the final visual acuity and binocular vision outcomes were examined.

RESULTS

The mean final visual acuity (logarithm of the minimum angle of resolution) of the operated eye was 0.43+/-0.33 for the IOL group and 0.58+/-0.39 for the CL group (p=0.14). The mean interocular difference in visual acuity was 0.22+/-0.29 for the IOL group and 0.56+/-0.31 for the CL group (p=0.042). The reoperation rate was 78% in the IOL group compared with 35% in the CL group (p=0.017). Esotropia or exotropia of more than 8 prism diopters were present in 55% of children (10/18) in the IOL group compared with 83% of children (19/23) in the CL group (p=0.039).

CONCLUSIONS

We suggest that correction of aphakia after unilateral congenital cataract surgery with primary IOL implantation results in improved visual acuity, improved binocular vision outcome and less occurrence of strabismus, but a higher rate of complications requiring reoperation. Further studies with a larger pediatric patient group are necessary to confirm the optimal treatment of aphakia after unilateral congenital cataract extraction.

Accuracy of intraocular lens calculations in infants and children undergoing cataract surgery

PURPOSE

We sought to evaluate the accuracy of intraocular lens calculations in children undergoing cataract extraction with intraocular lens (IOL) implantation.

METHODS

This was a retrospective review of 101 consecutive cases of pediatric cataract extraction with posterior chamber IOL. Median age at the time of surgery was 4.8 years, and 23 of the children were younger than 2 years of age. Initial IOL calculations were made using either the SRK II or SRK T formulas. Preoperative predictive data were compared with the refractive result obtained at the 2-month postoperative visit. Prediction error was calculated for each patient, and lens calculation errors were back-calculated for each of 4 commonly used IOL calculation formulas, including the SRK II, SRK T, Holladay I, and Hoffer Q.

RESULTS

The mean prediction error for all patients was 0.30 D. Despite this level of overall accuracy, significant variability did occur with outcomes ranging from -4.06 D to + 3.86 D of the desired spherical equivalent. Mean absolute prediction error was 1.16 D with no significant difference between the SRK II and SRK T formulas. Lens calculation errors predicted by each of the 4 formulas studied demonstrated a high degree of variability with the SRK II being the least variable and the Hoffer Q being the most variable, particularly among the youngest group of children with the axial lengths less than 19 mm.

CONCLUSIONS

The accuracy of commonly used IOL calculation formulas is generally reasonable but highly variable within the pediatric population, Newer theoretic IOL calculation formulas did not outperform older regression models.

Use of the aphakic refraction in intraocular lens (IOL) power calculations for secondary IOLs in pediatric patients

PURPOSE

Calculating the power of a secondary intraocular lens (IOL) requires axial lengths and keratometry measurements. In children, these measurements often need to be done under either sedation at the time of surgery or additional sedation. We devised a method of calculating IOL power using only the aphakic refraction and a standard keratometry value.

PATIENTS AND METHODS

This retrospective study included children undergoing a secondary IOL procedure who had IOL calculations based on either a measured axial length and a measured keratometry value (with sedation if needed) or a calculated axial length and a standard keratometry value. Comparison of predicted postoperative refraction with actual postoperative refraction was used to evaluate each method.

RESULTS

The mean difference between predicted and actual postoperative refractions was 2.34 D for the group with actual measurements and 2.50 D for the group with the calculated value method.

CONCLUSION

The use of the aphakic refraction to calculate axial length and a standard keratometry value provides an alternative for secondary IOL calculations in pediatric patients when ultrasonic or nonsedated ultrasonic axial length measurements are not an option.

Management of paediatric traumatic cataract by epilenticular intraocular lens implantation: long-term visual results and postoperative complications

PURPOSE

This study was carried out to evaluate the postoperative visual results and complications following epilenticular intraocular lens implantation in paediatric traumatic cataracts.

MATERIALS AND METHODS

A total of 30 patients undergoing epilenticular intraocular lens implantation for traumatic pediatric cataract were evaluated prospectively for visual results and complications. After-cataract formation was the prime area of interest. Follow-up of patients ranged from 2 to 8 years (mean 5 years). In all, 90% of eyes had a visual acuity of 6/60 or worse at the time of presentation.

RESULTS

In total, 80% of our patients achieved a visual acuity of 6/12 or better postoperatively after a mean follow-up of 5 years. None of our patients had after-cataract formation and the visual axis remained clear until the last follow-up in all the patients.

CONCLUSION

Epilenticular intraocular lens implantation in paediatric traumatic cataracts is associated with favourable anatomic and visual results.

Contact lenses for the treatment of pediatric cataracts

OBJECTIVE

To evaluate the experiences, attitudes, and perceptions of the caregivers of children with cataracts who were visually rehabilitated with contact lenses.

PARTICIPANTS

One hundred twenty-three caregivers of children <8.1 years old treated for unilateral and bilateral cataracts at one pediatric hospital.

DESIGN

Survey by questionnaire.

INTERVENTION

Primary caregivers were asked to complete an anonymous questionnaire.

MAIN OUTCOME MEASURES

Caregiver responses to questions assessing background and demographic and clinical information, as well as perceptions, attitudes, levels of compliance, and anxiety with respect to treatment, were reviewed. Caregivers were also asked to choose between aphakic rehabilitation with contact lenses, aphakic glasses, or intraocular lenses, given various hypothetical scenarios differing in regard to their final visual prognosis, risks of treatment complications, and cost.

RESULTS

The response rate was 82.9%. Absolute average stress levels for contact lens use were 1.36 +/- 1.79 and 0.79 +/- 1.48 (scale, 0-5) for insertion and removal, respectively, compared with 4.03 +/- 1.64 and 2.40 +/- 1.92 for cataract surgery and patching therapy, respectively. Although average paired initial resistance to treatment (RT) levels for contact lens insertion and removal on a scale of 0 to 3 were high (2.09 +/- 1.15) and moderate (1.63 +/- 1.20), respectively, final RT levels were significantly lower (1.09 +/- 1.14 and 0.66 +/- 1.07, respectively; P < 0.0001). The vast majority of caregivers chose contact lens use in hypothetical scenarios that depicted realistic expectations for other forms of aphakic rehabilitation.

CONCLUSIONS

In our study, contact lenses seemed to be well tolerated by most patients, as assessed by caregivers. Although initial resistance to contact lens use is high, this decreases with time. Relative to other events in the treatment of pediatric cataracts, contact lens use is not a major stressor for most caregivers and patients. This study supports the notion that contact lenses should continue to receive serious consideration as a treatment option for pediatric cataracts.

Minimal myopic shift in pseudophakic versus aphakic pediatric cataract patients

PURPOSE

To evaluate postoperative refractive changes in aphakic and pseudophakic children in a comparative case series.

METHODS

The medical records of pediatric patients with aphakia and pseudophakia were reviewed retrospectively. The mean change in refractive error from one postoperative examination to the next was calculated at each age to give aggregate curves of postoperative refractive change for each group.

RESULTS

A total of 233 aphakic and 92 pseudophakic eyes were studied. The median age at the time of surgery was 0.8 years (range, 0.0-16 years) for patients with aphakia and 7.3 years (range, 1.5-19.9 years) for patients with pseudophakia (P <.0001). The postoperative refraction curves at comparable ages of 2 to 20 years showed a total mean myopic shift of 1.5 D for patients with pseudophakia and 7.8 D for patients with aphakia. An age-matched subset of patients with aphakia also showed more myopic shift than those with pseudophakia.

CONCLUSIONS

Pseudophakic eyes show less postoperative myopic shift than aphakic eyes. Selecting intraocular lens powers aimed at producing initial emmetropic refractions has been a good strategy in our cohort of patients with pseudophakia. However, our data are insufficient for conclusions regarding children with pseudophakia younger than 2 years, in whom larger myopic shifts may occur.

When may the posterior capsule be preserved in pediatric intraocular lens surgery?

PURPOSE

To refine indications for primary posterior capsulotomy (PPC) in conjunction with posterior chamber intraocular lens (PCIOL) implantation for cataract in childhood.

DESIGN

Noncomparative case series.

PARTICIPANTS

Patients 1 to 13 years old who underwent cataract extraction with intent to preserve the posterior lens capsule and PCIOL implantation between January 1992 and December 1998 at a pediatric hospital.

METHODS

Medical records were reviewed to determine the frequency and timing of posterior capsule opacification (PCO) after PCIOL surgery with preservation of an intact posterior capsule. Comparison of pseudophakic PCO rates for groups defined by age and several possible risk factors. Assessment of safety and efficacy for PPC with anterior vitrectomy performed through a limbal incision in cases where the posterior capsule could not be preserved.

MAIN OUTCOME MEASURES

Need for neodymium:yttrium-aluminum-garnet laser capsulotomy or surgical membranectomy to treat PCO.

RESULTS

PCO occurred in 40% of 30 eyes with intact posterior capsule. Mean follow-up duration was 22 months for eyes that had PCO develop and 24 months for those in which the posterior capsule remained clear. Laser capsulotomy was required for 64% of 14 eyes in the 1- to 6-year-old age range but for only 19% of 16 in the 6- to 13-year-old range (P < 0.05). Mean time from surgery to PCO was 7 months for the younger group and 13 months for the older group. A need for repeated capsulotomy (one eye) or membranectomy with anterior vitrectomy (two eyes) was found only in the younger age group. There was no association of PCO with trauma history, cataract type, residual lens cortex, IOL position, or postoperative fibrin clot. Final vision was possibly compromised as a result of PCO in one eye with amblyopia. None of 24 eyes in which PPC with anterior vitrectomy was performed out of intraoperative necessity before primary PCIOL implantation had secondary opacification develop. No reduction in postoperative vision was attributable to PPC.

CONCLUSIONS

PPC seems to be advisable for children less than 6 years old when cataract extraction with PCIOL implantation is performed. Preservation of the posterior capsule remains appropriate for older children with pseudophakia.

Complications in the first year following cataract surgery with and without IOL in infants and older children

PURPOSE

The optimal role of intraocular lenses (IOLs) in infants remains a controversial topic for many reasons, including concerns about significant complications occurring in young rapidly developing eyes.

METHODS

To assess the number and type of significant complications requiring further intervention occurring in the first postoperative year, we reviewed the records of 15 eyes of 13 infants undergoing lensectomy with posterior chamber IOL and pars plana vitrectomy (PPV)/capsulectomy under 6 months (group A) of age as part of an ongoing prospective study of IOL use in infants. This group was compared with a group of 16 children age 10 months to 5 years undergoing an identical procedure (group B) and a group of 33 infants less than 6 months of age undergoing lensectomy/vitrectomy without IOL (group C).

RESULTS

Thirteen of 15 eyes in group A required additional surgery in the first postoperative year. Twelve of the 15 eyes (80%) developed secondary opacification across the visual axis posterior to the IOL requiring a second PPV and one eye developed pseudophakic glaucoma. Two patients required a third PPV to keep the visual axis clear. In group B, 0 of 16 (P <.0001) developed secondary opacification of the visual axis. In group C, 4 of 33 (12%; P <.0001) developed pupillary opacification in the first postoperative year.

CONCLUSIONS

Intraocular lens implants in infants may be associated with a higher complication rate requiring further surgery during the first postoperative year than is lensectomy/vitrectomy surgery without IOL implant in infants or lensectomy/IOL/vitrectomy surgery in children older than 6 months of age.

Accuracy of intraocular lens power calculation in paediatric cataract surgery

AIMS

To determine the accuracy of intraocular lens (IOL) power calculation in a group of pseudophakic children.

METHODS

A retrospective analysis of biometric and refractive data was performed on 52 eyes of 40 infants and children, who successfully underwent cataract extraction and IOL implantation. The following parameters were included: age at the time of surgery, keratometry, axial length, estimated refraction, and the power of IOL implanted. The postoperative refractive outcome was taken as the spherical equivalent of the refraction at 3 months after surgery. The prediction error was taken as the absolute difference between the estimated and actual postoperative refraction. The data were analysed to assess the effects of age at the time of surgery, keratometry, and axial length on the accuracy of calculation of IOL power.

RESULTS

For the overall group the mean and median prediction errors were 1.40 D and 0.84 D (SD 1.60). The mean and median prediction errors in eyes with axial lengths > or =20 mm were 1.07 D and 0.71 D (SD 0.98) and in eyes <20 mm were 2.63 D and 2.61 D (SD 2.65). The mean and median prediction errors in eyes in children aged > or =36 months were 1.06 D and 0.68 D (SD 1.02) and in children aged <36 months was 2.56 D and 2.29 D (SD 2.50). The differences between the prediction errors for both axial length and age were statistically significant (p<0.05).

CONCLUSIONS

For the overall group IOL power calculation is satisfactory. In eyes with axial lengths less than 20 mm and in children less than 36 months of age larger errors can arise. This study demonstrates the need for an IOL formula specifically designed for paediatric use.

Visual outcome in patients with isolated autosomal dominant congenital cataract

OBJECTIVE

To determine the visual outcome and surgical complication rates of patients with isolated inherited congenital cataract.

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

Patients and their families were ascertained from the genetic eye clinic and outpatient databases of Moorfields Eye Hospital, London, and invited to participate in the study. Four hundred twenty-two individuals from 72 pedigrees with this form of autosomal dominant cataract underwent ophthalmologic assessment.

MAIN OUTCOME MEASURES

Visual acuity and surgical complications (glaucoma, retinal detachment, amblyopia).

RESULTS

In this study 49.4% of patients (46.8% of those operated) achieved a visual acuity (VA) of 20/40 or better, 35.9% (36.1% of those operated) a VA between 20/50 and 20/200, and 14.7% (17.1% of those operated) worse than 20/200. Opacities that were more diffuse or did not lie close to the visual axis were associated with a better prognosis for vision; 6.6% had glaucoma and 5.0% had retinal detachment develop.

CONCLUSIONS

Patients with isolated inherited congenital cataract have a better visual and surgical outcome than those with coexisting ocular and systemic abnormalities. The improved prognosis is related in part to the lack of other developmental abnormalities of the eye, and, because inherited cataracts are often partial at birth, surgery may be delayed to later infancy and childhood when there is a lower incidence of surgical complications and refractive correction is easier. Certain inherited phenotypes (lamellar, pulverulent, polymorphic, coralliform, and cortical) also seem to have a better prognosis, and this should be borne in mind when counseling these families. A large number of the patients in this study underwent surgery many years previously, when surgical outcomes were less favorable, and thus the results of this study establish only a minimum acuity dataset for the purposes of counseling.