CUGC for congenital primary aphakia

Congenital Malformations of the Eye: A Pictorial Review and Clinico-Radiological Correlations

Congenital malformations of the eye represent a wide and heterogeneous spectrum of abnormalities that may be part of a complex syndrome or be isolated. Ocular malformation severity depends on the timing of the causative event during eye formation, ranging from the complete absence of the eye if injury occurs during the first weeks of gestation, to subtle abnormalities if the cause occurs later on. Knowledge of ocular malformations is crucial to performing a tailored imaging protocol and correctly reporting imaging findings. Together with the ophthalmologic evaluation, imaging may help frame ocular malformations and identify underlying genetic conditions. The purpose of this pictorial review is to describe the imaging features of the main ocular malformations and the related ophthalmologic findings in order to provide a clinico-radiological overview of these abnormalities to the clinical radiologist. Sight is a crucial sense for children to explore the world and relate with their parents from birth. Vision impairment or even blindness secondary to ocular malformations deeply affects children's growth and quality of life.

The growth and shape of the eyeball and crystalline lens in utero documented by fetal MR imaging

Purpose

To study the growth model, shape, and developmental relationship of lens and eyeball, we used two-dimensional Magnetic Resonance (MR) imaging to investigate gestationally age-related changes in the selected ocular parameters in vivo.

Materials and methods

We retrospectively reviewed the MR images from 126 fetuses ranging from 21 to 39 weeks' gestation. Ocular parameters on MR imaging of transverse plane were measured including lens diameter (LD), anteroposterior lens diameter (APLD), lens surface area (LS), globe diameter (GD), anteroposterior globe diameter (APGD), globe surface area (GS). The growth model of each biometric against gestational age (GA), aspect ratio of lens and globe (LD/APLD and GD/APGD), and growing relationship between the ratio of lens and globe surface area (LS/GS) were studied by statistical analysis.

Results

The growth model of most biometry for gestational age is logarithmic, except for the diameter of the ocular globe (GD and APGD) showing a quadratic growth pattern. Our study showed that the lens was consistently larger in the transverse than the anteroposterior diameters during 21-39 weeks(P < 0.001). Besides, the ratio of surface area (LS/GS) was not significantly changing with GA(P = 0.4908), while the increase of LS was significantly accorded with that of GS(P < 0.001).

Conclusion

The lens shape throughout fetal life may take part in the process, shape changing from vertical ellipsoid, spherical to transversal ellipsoid, based on the logarithmically increased ratio of lens transverse and anteroposterior diameters. In the meanwhile, the aspect ratio of eyeball in late fetal life may imply a gradually spherical shape during gestation. Nomogram data from this study may provide appropriate information about morphological changes in the fetal lens and the synchronous relationship between lens and eyeball.

Primary aphakia: clinical recognition is the key to diagnosis

PURPOSE

To describe the presentation and treatment outcomes of a cohort of children with primary aphakia (PA).

METHODS

Clinical photographs and ultrasound biomicroscopy (UBM) images of children presenting with sclerocornea and undetermined anterior segment dysgenesis between July 2017 and December 2020 were reviewed retrospectively. Children who had no crystalline lens visible on UBM were included.

RESULTS

A total of 124 UBM images were captured for 124 children with cloudy corneas. Twelve children were identified with congenital primary aphakia: 5 had bilateral buphthalmos, 2 had buphthalmos in one eye and microphthalmos in the other, and 5 had bilateral sclerocornea-microphthalmia complex. All patients had a peculiar silvery-blue corneal appearance, with fine vascularization on the corneal surface. The overall corneal thickness was 409.1 ± 8.7 μm. The intraocular pressure (IOP) in eyes with glaucoma was 24.5 ± 7.3 mm Hg; in microphthalmic eyes, 11.4 ± 3.4 mm Hg (P <0.001). The raised IOP was treated with limited trans-scleral cyclophotocoagulation under transillumination and topical antiglaucoma medications. Children with glaucoma gained ambulatory vision with spectacles.

CONCLUSIONS

Congenital primary aphakia has a characteristic clinical appearance and may present as buphthalmos or microphthalmos, depending on the extent of dysgenesis. Incisional surgery may result in phthisis because of ciliary body dysgenesis and unpredictable aqueous production.

Novel prenatally diagnosed compound heterozygous PXDN variants in fetal congenital primary aphakia and blepharophimosis

OBJECTIVE

To precision survey a fetal congenital primary aphakia molecular etiology.

CASE REPORT

A case of 42 years old pregnancy woman prenatal diagnostic examination by amniocentesis conducted at 17 weeks' gestation and demonstrated a normal female karyotype. Trio studies based on chromosome microarray analysis (CMA) and Sanger's genetic analysis did not detect a pathologic variant of the FOXE3 gene. Fetal congenital primary aphakia accompanied with microphthalmia detected by sonography in the second trimester (22 weeks). MRI indicated bilateral absence of the lenses, consistent with primary congenital aphakia. Due to the poor prognosis of congenital aphakia, the parents decided to terminate the fetus and provided consent for an autopsy. Pathological analysis revealed dysplasia of the anterior segment of both eyes. However, post fetal mortem extended trio whole exon sequencing (WES) and Sanger's genetic analysis identified compound heterozygous variants in the chromosomal location 2p25.3 in the PXDN gene.

CONCLUSION

Extended whole exon sequencing is an important tool to study primary congenital aphakia.