Fetal Cataract Research Articles

Postnatal ophthalmological characteristics in patients with congenital cataract diagnosed by fetal ultrasonography

Purpose To evaluate the findings of postnatal ophthalmological examinations in patients diagnosed with cataracts by prenatal fetal sonography. Methods We retrospectively identified patients diagnosed with fetal cataract without other ocular abnormalities using antenatal ultrasound. We analyzed data including the patients’ family history, the presence of metabolic or systemic disease-associated cataracts, gestational age at diagnosis, fetal sonography reports, and the results of postnatal ophthalmological examinations. Results In total, eight patients were diagnosed with cataracts by prenatal fetal ultrasonography, and all these patients showed mild to severe degrees of cataract after birth. Patients showed hyperechoic opacity of the lens in the available images. The mean gestational age at diagnosis was 26 ± 3 weeks (range, 22–28 weeks), and three patients (37.5%) had a family history of congenital cataract. All patients, except one patient who had patent ductus arteriosus, showed no systemic abnormalities associated with cataracts on postnatal evaluation. Six (75.0%) were diagnosed with bilateral cataracts after birth, and of these, two patients had been diagnosed with unilateral left cataract prenatally. Postnatal ophthalmological examination revealed that all patients showed opacities involving the nucleus of the lens and three patients (37.5%) had associated abnormalities of microcornea or microphthalmia, which were not diagnosed antenatally. Conclusion In all our subjects, the lens opacities on prenatal fetal sonography were diagnosed postnatally as cataracts involving the nucleus. A careful postnatal examination is essential to detect the presence of associated ocular abnormalities such as microcornea and/or microphthalmia and cataract in the contralateral eye in patients with congenital cataract.

Prenatal Ultrasonographic Diagnosis of Cataract: In Utero Manifestations of Cryptic Disease.

To report and review our experience with antenatal evaluation for fetuses diagnosed with congenital cataract. We retrospectively identified pregnancies diagnosed with fetal cataract during antenatal ultrasound. Evaluation of fetal eyes included intraocular anatomy and biometry. Data on fetal malformations, serology and fetal karyotype were collected. 8 cases, identified over the course of 10 years, were reviewed. Week 15 was the mean time for diagnosis (range 11 - 34). Extraocular anomalies were demonstrated in 6 cases (central nervous system, cardiac and renal systems). Additional intraocular abnormalities were detected in two cases: one fetus had persistent hyperplastic primary vitreous and another had bilateral retinal detachment. All cases but one involved cataracts in both eyes. The unilateral case was associated with microphthalmic aphakia. All cases had negative serology for TORCHs. 7 out of the 8 fetuses were terminated. The only one who survived developed in utero cataracts secondary to maternal steroid therapy. He underwent bilateral cataract extraction during the first weeks of life and ophthalmologic evaluation at 2 years of age was unremarkable, without any visual impairment. In most cases, fetal cataract was associated with additional abnormalities, both intra- and extra-ocular. In instances when cataracts are isolated, we suggest conducting a detailed and thorough in utero ophthalmic examination in order to improve antenatal parental counselling.

Lens artifacts in human fetal eyes — the challenge of interpreting the histomorphology of human fetal lenses

Evaluation of the lens, including cataractous changes, is often of paramount importance in the classification of fetal syndromes or forensic questions. On histology, the crystalline lens is - especially in fetal and infant eyes - an organ susceptible to numerous artifacts. Thus, the aim of our study was to study various factors (including fixatives) that might have an impact on lens histomorphology. Twenty eyes from ten fetuses (formalin fixation: n = 10, glutaraldehyde fixation: n = 10), matched for gestational age and abortion (spontaneous vs. induced), were investigated macroscopically and by light microscopy. Sections were stained with routine hematoxylin & eosin (H&E), and periodic acid schiff (PAS). The age of the fetal eyes ranged from 15 to 36weeks of gestation. Lens artifacts were analyzed and compared to fetal and adult lenses with definitive cataractous changes. In addition, 34 eyes from 27 fetuses with trisomy 21 were investigated for lens changes. All lenses showed artifacts of varying extent, in particular globules, vacuoles, clefts, anterior/posterior capsular separation, subcapsular proteinaceous material, fragmentation of the lens capsule/epithelium, and a posterior umbilication. Glutaraldehyde-fixed lenses displayed less artifacts compared to those fixed in formalin. Slight differences in the appearance of artifacts were found dependent on the fixative (formaldehyde vs glutaraldehyde) and the kind of abortion (iatrogenous vs spontaneous). The gestational age did not have a significant influence on the type and extent of lens artifacts. The lenses from fetuses with trisomy 21 displayed similar lens artifacts with no specific findings. Alterations in fetal lens morphology are extremely frequent and variable. These artifacts have to be carefully taken into account when interpreting post-mortem findings. Thus, the postmortem diagnosis of a fetal cataract should be made with great caution, and should include, in adherence to our proposed diagnostic flow diagram, the macroscopic lens assessment. Reference slides with a proven cataract are recommended for comparison in equivocal cases.

Congenital cataract in a child with pyridoxine-dependent epilepsy

Pyridoxine-dependent epilepsy (PDE) is a cause of neonatal epileptic encephalopathy not previously known to cause ophthalmic disease. We describe the novel observation of a 5-year-old girl with pyridoxine-dependent epilepsy and bilateral cataracts. PDE is the result of mutations in the ALDH7A1 gene encoding antiquitin, an enzyme protective against cellular dehydration and osmotic stress. Accumulating metabolic precursors in PDE have been shown to be cataractogenic in vitro, and experimental pyridoxine deficiency has been associated with lenticular opacities in vivo. The association of ALDH7A1 haploinsufficiency in PDE and congenital cataract may offer insight into the relationship between osmotic stress and fetal cataract development. Bilateral progression of cataracts in this child suggests ongoing metabolic dysregulation within the crystalline lens despite pyridoxine supplementation at doses sufficient to control seizure activity.

Morphologic Analysis of Artifacts in Human Fetal Eyes Confounding Histopathologic Investigations

Human fetal eyes are an excellent source for studies of the normal ocular development and for examining early ocular changes associated with various syndromes in the context of a pediatric pathologic or prenatal sonographic diagnosis. However, artifacts caused by different factors often render an exact interpretation difficult. In this study, the frequency and extent of artifacts in human fetal eyes were investigated with the aim of distinguishing more precisely these artifacts from real findings, allowing also for a more diligent forensic interpretation. The cohort included 341 fetal eyes, ranging in age from 8 to 38 weeks of gestation, that were investigated macroscopically and by light microscopy. In most specimens, artifacts such as pigment spillage and autolytic changes of the retina were noted. Nearly all specimens showed changes of the lens with remarkable similarities to cataractous lenses in adult eyes. Structural ocular changes associated with systemic syndromes were also observed and in most instances could be distinguished from artifacts. Morphologic changes in fetal eyes should be classified in artifacts caused by way of abortion, mechanical effects from the removal of the eyes, delayed fixation with autolysis, and the fixative itself and should be distinguished from genuine structural abnormalities associated with ocular or systemic disease. This classification can be fairly difficult and requires experience. In addition, lens artifacts are often misleading, and the diagnosis of a fetal cataract should not be made based on histopathologic examination alone.

The challenge of interpreting the histomorphology of human fetal lenses

Abstract Purpose On histology, the crystalline lens is – especially in fetal and infant eyes ‐ an organ susceptible to numerous artifacts. Nevertheless, evaluation of the lens is often of paramount importance in the classification of fetal syndromes or forensic questions. Thus, the aim of our study is to evaluate various factors that might have an impact on lens histomorphology. Methods Our collection of eyes by now comprises more than 500 specimens from fetuses with a gestational age between 8 and 38 weeks, including a variety of syndroms. Apart from induced fetocid, death occured due to spontaneous abortion or post‐natally. Specimens were fixed in formalin, and in selected cases one eye was put into Karnovsky's solution for comparison. All systemic findings as well as data related to the termination procedure were recorded. ‐ Some individual cases shall be presented to demonstrate the variability of histopathologic findings. Results Most of the eyes revealed lens features different from the descriptions available in textbooks. At all ages, there were various morphologic changes particularly of the subcapsular cortex, compatible with cataractous lenses in the adult, while the well‐known phenomenon of an indentation at the posterior pole was seen especially in older fetuses. The difference in fixatives had only a moderate impact on structural alterations. Conclusion Alterations in fetal lens morphology are extremely frequent and variable. These can be due to delayed fixation, cutting artifacts and other variables and have to be carefully taken into account particularly when interpreting post‐mortem findings. The diagnosis of a fetal cataract should therefore only be made with great caution and not without a careful macroscopic evaluation.