Ray Arkaprava, Gurnani Bharat
Gomabai Netralaya and Research Centre
Pediatric cataracts are a leading cause of treatable childhood blindness. If left unaddressed, cataracts can have substantial social, economic, and emotional consequences for the affected child, family, and broader community. Effective management remains challenging due to the critical need for early identification, diagnosis, and intervention to prevent irreversible amblyopia. Routine screening and parental awareness of early signs, such as leukocoria and strabismus, facilitate timely diagnosis and treatment. Favorable visual outcomes depend on comprehensive preoperative assessment, accurate intraocular lens (IOL) power calculation, meticulous surgical technique, and coordinated postoperative care, including visual rehabilitation. Optimal management requires an interprofessional approach involving pediatrics, anesthesiology, ophthalmology, and optometry. Pediatric cataracts are a major cause of preventable childhood blindness worldwide, particularly in developing countries, where delayed diagnosis often leads to advanced presentations such as nystagmus, poor fixation, and dense cataracts. Early intervention significantly improves visual outcomes and enhances the affected child’s personal and social development, while also alleviating the socioeconomic burden on families. Globally, pediatric cataracts account for approximately 5% to 20% of childhood blindness and severe visual impairment, with an estimated incidence of 1.8 to 3.6 per 10,000 children per year and a prevalence ranging from 1 to 15 per 10,000 children. Population-based data show similar trends in high-income settings. Holmes et al reported a prevalence of 3 to 4 visually significant cataracts per 10,000 live births in the United States. A study by Rahi et al in the United Kingdom found a prevalence of 3.18 per 10,000 live births, while Nile et al reported an incidence of approximately 5 per 10,000 births in China. Despite regional differences in detection and reporting, consistent findings across studies indicate no significant laterality or sex predilection. Hereditary congenital cataracts have a prevalence between 8.3% and 25%, with about 75% of cases following an autosomal dominant inheritance pattern. Pathogenic variants in crystallin proteins, which are essential for maintaining lens transparency and refractive function, have been associated with several cataract subtypes, including nuclear, lamellar, zonular, and posterior polar cataracts. Nonsyndromic inherited cataracts frequently involve genetic alterations in crystallin or connexin genes. mutations are specifically linked to posterior polar cataracts, while alterations are associated with anterior polar cataracts. Syndromic cataracts are linked to specific genetic defects, including galactosidase-α in Fabry disease, galactose-1-phosphate uridyltransferase (GALT) in galactosemia, OCRL in Lowe (oculocerebrorenal) syndrome, and NHS in Nance–Horan syndrome, a cataract–dental disorder (see Congenital Cataracts and Abnormal Galactose Metabolism). Maternal and congenital infections, particularly , rubella, cytomegalovirus, herpes simplex virus, and (syphilis)—collectively known as TORCH pathogens—are also major contributors to pediatric cataracts. B Mahalakshmi et al reported a high prevalence of TORCH infections in the Indian subcontinent, with 20% of cases testing seropositive. Ocular trauma is another significant cause, accounting for 12% to 46% of pediatric cataract cases. Concerns exist regarding the higher incidence of complications, such as glaucoma, uveitis, dense posterior capsule opacification (PCO), and increased secondary interventions following primary IOL implantation in children younger than 2 years. However, primary IOL implantation in these young individuals has been shown to be safe, with excellent long-term outcomes compared to aphakia and secondary IOL implantation after age 2. The myopic shift is generally well-controlled, visual acuity outcomes are favorable, and the incidence of complications, such as glaucoma, uveitis, membrane formation, synechiae, and the need for secondary interventions, is lower than previously reported. Special care is necessary for children younger than 6 months due to the high risk of adverse events in smaller eyes. The process of emmetropisation in children is typically complete by age 12, with axial length increasing from approximately 16.5 mm at birth to 23 mm by age 13. This growth occurs in 3 phases: the rapid phase (0.46 mm/month from birth to 6 months), the infantile phase (0.15 mm/month from 6 to 18 months), and the juvenile phase (from 18 months to 12 years). Corneal curvature also changes significantly, with mean keratometry readings decreasing from approximately 51.2 D at birth to 43.5 D in adulthood. Consequently, the power of the IOL implanted in children must be adjusted to account for both axial elongation and the accompanying myopic shift. This adjustment requires the use of customized IOL power calculation formulas suited to growing pediatric eyes. Sharp-edged IOLs are now widely preferred due to their association with lower rates of visual axis opacification (VAO), resulting in fewer neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomies compared to round-edged lenses (1/371 vs 4/371). Prompt management of pediatric cataracts is essential for optimal visual development. Most children with congenital or developmental cataracts will require surgical intervention. The degree of visual impairment may be initially assessed using the red reflex during distant direct ophthalmoscopy (see . Red Reflex). For visually significant cataracts, bilateral cases should be treated between 6 and 8 weeks of age, while unilateral cases require earlier intervention, typically between 4 and 6 weeks.
小儿白内障是儿童可治疗性失明的主要原因之一。未经治疗的白内障会在社会、经济和情感方面对患病儿童、家庭以及整个社会产生重大影响。小儿白内障仍然是眼科临床实践中的一项挑战,因为需要尽早识别、诊断和处理病情以预防弱视。家长对白瞳症和斜视进行常规筛查并提高认识,有助于早期诊断和治疗。良好的术前评估、人工晶状体(IOL)屈光度计算、精细的手术以及同样高效的术后护理和视力康复,对于取得良好预后至关重要。涉及儿科、麻醉科、眼科和验光科的多部门协作,有助于妥善且有效地管理小儿白内障。小儿白内障是全球可预防失明的主要原因,在发展中国家尤为普遍,那里的晚期诊断常常导致眼球震颤、注视不良和完全性白内障等症状。早期干预可显著改善患病儿童的个人生活和社会生活,加强其视力康复,并对其家庭的社会经济状况产生积极影响。小儿白内障在全球儿童失明和严重视力损害中占5%至20%,每年每10000名儿童的发病率在1.8至3.6之间。全球患病率为每10000名儿童1至15例。霍姆斯等人发现,在美国每10000例活产中估计有3至4例具有明显视力影响的白内障。同样,拉希等人在英国进行的一项研究报告称,每10000例活产的患病率为3.18。尼罗等人报告称,中国每10000例出生中的发病率约为5例。尽管存在地域差异,但通常未报告明显的左右侧差异或性别差异。遗传性先天性白内障的患病率在8.3%至25%之间,约75%的病例遵循常染色体显性遗传模式。晶状体蛋白中的突变对于晶状体的透明度和屈光力至关重要,与各种类型的白内障有关,如核性、板层状、 zonular和后极性白内障。非综合征性遗传性白内障通常涉及晶状体蛋白和连接蛋白基因突变,PITX3突变与后极性白内障有关,PAX6与前极性白内障有关。综合征性白内障与基因突变有关,包括半乳糖苷酶-α(i型法布里病)、半乳糖血症中的1-磷酸半乳糖尿苷转移酶(GALT)、 Lowe综合征中的OCRL(Lowe眼脑肾综合征)以及Nance-Horan白内障-牙综合征中的NHS(见先天性白内障与异常半乳糖代谢)。母体感染和先天性感染,如风疹、巨细胞病毒、疱疹和梅毒(TORCHES),也是小儿白内障的重要病因,B·马哈拉克希米等人报告称,印度次大陆TORCH感染的发病率很高,发现2例呈血清阳性。外伤是另一个主要原因,占小儿白内障的12 - 46%。对于2岁以下儿童,人们担心原发性人工晶状体植入术后并发症的发生率较高,如青光眼、葡萄膜炎、后囊膜混浊(PCO)加重以及二次干预增加。然而,已证明在这些儿童中进行原发性人工晶状体植入是安全的,与无晶状体眼和2岁后进行二次人工晶状体植入相比,长期效果良好。近视漂移得到很好的控制,视力通常良好,青光眼、葡萄膜炎、膜形成、虹膜粘连和二次干预等并发症较少见。由于小眼睛发生不良事件的风险较高,6个月以下的儿童需要特别护理。儿童眼睛的正视化过程通常在12岁时完成,眼轴长度从出生时的平均16.5毫米增加到13岁时的23毫米。这个过程可分为快速期(从出生到6个月,每月0.46毫米)、婴儿期(从6个月到18个月,每月0.15毫米)和青少年期(从18个月到12岁)。眼睛的眼轴长度从出生时的16.5毫米平均增加到13岁时的23毫米。角膜曲率和平均角膜曲率读数也从出生时的51.2D变化到成人时的43.5D。因此,植入儿童的人工晶状体的屈光度必须进行调整,以适应随着年龄增长出现的近视漂移和角膜曲率变化。这种调整需要针对生长中的小儿眼睛定制人工晶状体屈光度计算公式。由于与较低的视觉混浊发生率相关,锐边人工晶状体现在已被广泛接受,与圆边人工晶状体相比,需要更少的钕钇铝石榴石晶状体切开术(1/371对4/371)。管理小儿白内障至关重要,因为及时干预对于最佳视力恢复至关重要。大多数先天性或发育性白内障患儿需要手术干预。白内障对视力的影响可以通过远距离直接检眼镜检查时观察到的红光反射来评估(见红光反射)。双侧具有明显视力影响的白内障应在6至8周龄之间摘除,而单侧具有明显视力影响的白内障应在4至6周龄时处理。