BACKGROUNDCongenital cataracts are lens opacities in one or both eyes of babies or children present at birth. These may cause a reduction in vision severe enough to require surgery. Cataracts are proportionally the most treatable cause of visual loss in childhood, and are a particular problem in low-income countries, where early intervention may not be possible. Paediatric cataracts provide different challenges to those in adults. Intense inflammation, amblyopia (vision is obstructed by cataract from birth which prevents normal development of the visual system), posterior capsule opacification and uncertainty about the final trajectory of ocular growth parameters can affect results of treatment. Two options currently considered for children under 2 years of age with bilateral congenital cataracts are: (i) intraocular lens (IOL) implantation; or (ii) leaving a child with primary aphakia (no lens in the eye), necessitating the need for contact lenses or aphakic glasses. Other important considerations regarding surgery include the prevention of visual axis opacification (VAO), glaucoma and the route used to perform lensectomy.OBJECTIVESTo assess the effectiveness of infant cataract surgery or lensectomy to no surgery for bilateral congenital cataracts in children aged 2 years and under.SEARCH METHODSWe searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 1); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 25 January 2022.SELECTION CRITERIAWe included all randomised controlled trials (RCTs) that compared infant cataract surgery or lensectomy to no surgery, in children with bilateral congenital cataracts aged 2 years and younger. This update (of a review published in 2001 and updated in 2006) does not include children over 2 years of age because they have a wider variety of aetiologies, and are therefore managed differently, and have contrasting outcomes.DATA COLLECTION AND ANALYSISWe used standard methods expected by Cochrane. Two review authors extracted data independently. We assessed the risk of bias of included studies using RoB 1 and assessed the certainty of the evidence using GRADE.MAIN RESULTSWe identified three RCTs that met our inclusion criteria with each trial comparing a different aspect of surgical intervention for this condition. The trials included a total of 79 participants under 2 years of age, were conducted in India and follow-up ranged from 1 to 5 years. Study participants and outcome assessors were not masked in these trials. One study (60 children) compared primary IOL implantation with primary aphakia. The results from this study suggest that there may be little or no difference in visual acuity at 5 years comparing children with pseudophakia (mean logMAR 0.50) and aphakia (mean logMAR 0.59) (mean difference (MD) -0.09 logMAR, 95% confidence intervals (CIs) -0.24 to 0.06; 54 participants; very low-certainty evidence), but the evidence is very uncertain. The evidence is very uncertain as to the effect of IOL implantation compared with aphakia on visual axis opacification (VAO) (risk ratio (RR) 1.29, 95% CI 0.23 to 7.13; 54 participants; very low-certainty evidence). The trial investigators did not report on the cases of amblyopia. There was little evidence of a difference betwen the two groups in cases of glaucoma at 5 years follow-up (RR 0.86, 95% CI 0.24 to 3.10; 54 participants; very low-certainty evidence). Cases of retinal detachment and reoperation rates were not reported. The impact of IOL implantation on adverse effects is very uncertain because of the sparse data available: of the children who were pseudophakic, 1/29  needed a trabeculectomy and 8/29 developed posterior synechiae. In comparison, no trabeculectomies were needed in the aphakic group and 2/25 children had posterior synechiae (54 participants; very low-certainty evidence).  The second study (14 eyes of 7 children under 2 years of age) compared posterior optic capture of IOL without vitrectomy versus endocapsular implantations with anterior vitrectomy (commonly called 'in-the-bag surgery'). The authors did not report on visual acuity, amblyopia, glaucoma and reoperation rate. They had no cases of VAO in either group. The evidence is very uncertain as to the effect of in-the-bag implantation in children aged under 1 year. There was a higher incidence of inflammatory sequelae: 4/7 in-the-bag implantation eyes and 1/7 in optic capture eyes (P = 0.04, 7 participants; very low-certainty evidence). We graded the certainty of evidence as low or very low for imprecision in all outcomes because their statistical analysis reported that a sample size of 13 was needed in each group to achieve a power of 80%, whereas their subset of children under the age of 1 year had only 7 eyes in each group. The third study (24 eyes of 12 children) compared a transcorneal versus pars plana route using a 25-gauge transconjunctival sutureless vitrectomy system. The evidence is very uncertain as to the effect of the route chosen on the incidence of VAO, with no cases reported at 1 year follow-up in either group. The investigators did not report on visual acuity, amblyopia, glaucoma, retinal detachment and reoperation rate. The pars plana route had the adverse effects of posterior capsule rupture in 2/12 eyes, and 1/12 eyes needing sutures. Conversely, 1/12 eyes operated on by the transcorneal route needed sutures. We graded the outcomes with very low-certainty because of the small sample size and the absence of a priori sample size calculation.AUTHORS' CONCLUSIONSThere is no high level evidence for the effectiveness of one type of surgery for bilateral congenital cataracts over another, or whether surgery itself is better than primary aphakia. Further RCTs are required to inform modern practice about concerns, including the timing of surgery, age at which surgery should be undertaken, age for implantation of an IOL and development of complications, such as reoperations, glaucoma and retinal detachment. Standardising the methods used to measure visual function, along with objective monitoring of compliance with the use of aphakic glasses/contact lenses would greatly improve the quality of study data and enable more reliable interpretation of outcomes.

PURPOSE. We measure neural responses associated with form and motion processing in children with anisometropia before and after treatment with spectacles and occlusion. METHODS. In this prospective, case-control treatment study, 10 children with anisometropia and amblyopia and 16 age-matched visually normal children participated. Steady-state visual evoked potentials (VEP) were recorded from electrodes over the occipital cortex. The visual stimulus comprised a horizontal bar grating into which Vernier offsets were introduced and withdrawn periodically at 3.75 Hz. The VEP amplitude at 3.75 Hz (first harmonic [1F]) and 7.5 Hz (second harmonic [2F]) were recorded to index the sensitivity of form/position-sensitive versus motion/transient-sensitive neural populations, respectively. Response amplitude at 1F and 2F were recorded over a series of 10 logarithmically spaced offset sizes before and after treatment. Main outcome measures are VEP amplitude versus displacement functions, interocular response amplitude differences. RESULTS. After relaxing into spectacles (minimally-treated state), form/position-sensitive responses in the dominant/less ametropic eye of the children with anisometropia were larger and responses in the more ametropic eye were smaller than those of controls. Motion-transient responses were equal to those of controls in the less ametropic eye, but were smaller than controls in the more ametropic eye. After treatment, responses did not differ from those of controls. CONCLUSIONS. Form and motion responses are differentially susceptible to neural deprivation via optical blur. Form responses are more plastic than motion responses in minimally-treated children with anisometropic amblyopia. Most treatment effects occurred above threshold range, suggesting some treatment effects are not detected clinically.

Despite a constellation of visual deficits in amblyopia, treatment endpoints typically focus around threshold measurements (eg. visual acuity). We examined neural responses to a stimulus containing both relative position and relative motion cues in children with amblyopia and age-matched controls. The visual responses were recorded across a wide range above and around threshold performance before and after clinical treatment.

Almost everything we know about visual functions in amblyopia other than visual acuity comes from adults, studied long after initial onset and often treatment of the disorder. Studies indicate that vernier and optotype measures are correlated in amblyopic adults. Here, we report fundamental differences between children and adults with strabismic amblyopia.

Aims Clinically, picture acuity tests are thought to overestimate visual acuity (VA) compared with letter tests, but this has not been systematically investigated in children with amblyopia. This study compared VA measurements with the LogMAR Crowded Kay Picture test to the LogMAR Crowded Keeler Letter acuity test in a group of young children with amblyopia. Methods 58 children (34 male) with amblyopia (22 anisometropic, 18 strabismic and 18 with both strabismic/anisometropic amblyopia) aged 4–6 years (mean=68.7, range=48–83 months) underwent VA measurements. VA chart testing order was randomised, but the amblyopic eye was tested before the fellow eye. All participants wore up-to-date refractive correction. Results The Kay Picture test significantly overestimated VA by 0.098 logMAR (95% limits of agreement (LOA), 0.13) in the amblyopic eye and 0.088 logMAR (95% LOA, 0.13) in the fellow eye, respectively (p<0.001). No interactions were found from occlusion therapy, refractive correction or type of amblyopia on VA results (p>0.23). For both the amblyopic and fellow eyes, Bland-Altman plots demonstrated a systematic and predictable difference between Kay Picture and Keeler Letter charts across the range of acuities tested (Keeler acuity: amblyopic eye 0.75 to −0.05 logMAR; fellow eye 0.45 to −0.15 logMAR). Linear regression analysis (p<0.00001) and also slope values close to one (amblyopic 0.98, fellow 0.86) demonstrate that there is no proportional bias. Conclusions The Kay Picture test consistently overestimated VA by approximately 0.10 logMAR when compared with the Keeler Letter test in young children with amblyopia. Due to the predictable difference found between both crowded logMAR acuity tests, it is reasonable to adjust Kay Picture acuity thresholds by +0.10 logMAR to compute expected Keeler Letter acuity scores.

Purpose We sought to compare intraocular pressure (IOP) measurements by Perkins tonometer and Tono-Pen in young children with primary congenital glaucoma (PCG). Methods This was a retrospective comparative case series. We reviewed the clinical records of all children with primary congenital glaucoma who underwent examinations under general anesthesia at Soroka University Medical Center between January 1999 and July 2002. Our main outcome measures were IOP with Perkins hand-held tonometer and Tono-Pen tonometer. Results A total of 28 eyes of 16 children were examined under general anesthesia. The mean IOP was 18 ± 6 mm Hg with the Perkins tonometer and 22 ± 8 mm Hg with the Tono-Pen. In 18 eyes, IOP was less than 21 mm Hg with the Perkins tonometer; these eyes had already undergone surgical procedures. The other 10 eyes with IOP greater than 21 mm Hg with the Perkins tonometer underwent surgery at the end of the examination under anesthesia. In eyes with IOP greater than 16 mm Hg (Group A, n = 18), a significant difference (p < 0.001) was found between the Perkins and Tono-Pen measurements, even although the values were strongly correlated (r = 0.60). In contrast, in eyes with IOP less than 16 mm Hg (Group B, n = 10) no statistically significant difference (p = 0.28) and good correlation (r = 0.78) were obtained. A difference of 5.8 ± 3.8 mm Hg and 0.6 ± 1.7 mm Hg between Perkins and Tono-Pen readings, respectively, was found in Groups A and B. Conclusions Tono-Pen readings disagree with Perkins tonometer measurements for measuring IOP in children with PCG who present with IOP greater than 16 mm Hg and tends to overestimate IOP. A further study with a similar population is necessary to confirm these results. We sought to compare intraocular pressure (IOP) measurements by Perkins tonometer and Tono-Pen in young children with primary congenital glaucoma (PCG). This was a retrospective comparative case series. We reviewed the clinical records of all children with primary congenital glaucoma who underwent examinations under general anesthesia at Soroka University Medical Center between January 1999 and July 2002. Our main outcome measures were IOP with Perkins hand-held tonometer and Tono-Pen tonometer. A total of 28 eyes of 16 children were examined under general anesthesia. The mean IOP was 18 ± 6 mm Hg with the Perkins tonometer and 22 ± 8 mm Hg with the Tono-Pen. In 18 eyes, IOP was less than 21 mm Hg with the Perkins tonometer; these eyes had already undergone surgical procedures. The other 10 eyes with IOP greater than 21 mm Hg with the Perkins tonometer underwent surgery at the end of the examination under anesthesia. In eyes with IOP greater than 16 mm Hg (Group A, n = 18), a significant difference (p < 0.001) was found between the Perkins and Tono-Pen measurements, even although the values were strongly correlated (r = 0.60). In contrast, in eyes with IOP less than 16 mm Hg (Group B, n = 10) no statistically significant difference (p = 0.28) and good correlation (r = 0.78) were obtained. A difference of 5.8 ± 3.8 mm Hg and 0.6 ± 1.7 mm Hg between Perkins and Tono-Pen readings, respectively, was found in Groups A and B. Tono-Pen readings disagree with Perkins tonometer measurements for measuring IOP in children with PCG who present with IOP greater than 16 mm Hg and tends to overestimate IOP. A further study with a similar population is necessary to confirm these results.

Case report of a 16-year-old boy presenting with total hyphema due to blunt trauma to the left eye. During a subsequent cinematic MRI scan to identify salvageable lateral rectus muscle, the attachment of the left lateral rectus was obscured by a 20-mm diameter signal void. A subsequent CT scan for a suspected metallic foreign body revealed the muscle attachment after all. The theoretical explanations for this finding are discussed