Visual prognosis of posterior and combined persistent fetal vasculature

Outcomes and surgical management of persistent fetal vasculature

Objective

To analyse outcomes in different forms of persistent fetal vasculature (PFV).

Methods and analysis

Retrospective cohort study at a university-based practice of children presenting with PFV between 2011 and 2020. Exclusion criteria was surgical management outside of our institution and follow-up less than 1 month. Wilcoxon and Student’s t-tests were used for statistical analysis.

Results

Forty-six eyes of 45 patients presented with PFV at 16.7±31.3 (median 2.8) months old with 32.6±29.8 (median 22.5) months of follow-up. Types of PFV included: mild combined anterior-posterior (23 eyes, 50%), severe combined anterior-posterior (18 eyes, 39%), severe anterior (3 eyes, 7%), mild anterior (1 eye, 2%) and posterior (1 eye, 2%). Thirty-two eyes (70%) underwent PFV surgical correction; lensectomy (13 mild combined), vitrectomy (3 mild combined), sequential lensectomy then vitrectomy (3 severe combined), combined lensectomy-vitrectomy (11 severe anterior or severe combined), laser retinopexy (1 mild combined). Five eyes required additional vitrectomy surgery for retinal detachment, fold or cyclitic membrane. Nine eyes developed glaucoma, six requiring Intraocular pressure (IOP)-lowering surgery. At final follow-up, 32 eyes had at least form vision and 6 eyes were aversive to light. Eight eyes, all which were severe combined, and four that did not undergo PFV surgery, were unable to detect light due to phthisis bulbi (7) and optic nerve hypoplasia (1).

Conclusions

Classification of PFV is important in determining surgical approach with severe cases often requiring both lensectomy and vitrectomy for optimal anatomic and functional outcomes.

Ocular coloboma: Genetic variants reveal a dynamic model of eye development

Ocular coloboma is a congenital disorder of the eye where a gap exists in the inferior retina, lens, iris, or optic nerve tissue. With a prevalence of 2-19 per 100,000 live births, coloboma, and microphthalmia, an associated ocular disorder, represent up to 10% of childhood blindness. It manifests due to the failure of choroid fissure closure during eye development, and it is a part of a spectrum of ocular disorders that include microphthalmia and anophthalmia. Use of genetic approaches from classical pedigree analyses to next generation sequencing has identified more than 40 loci that are associated with the causality of ocular coloboma. As we have expanded studies to include singleton cases, hereditability has been very challenging to prove. As such, researchers over the past 20 years, have unraveled the complex interrelationship amongst these 40 genes using vertebrate model organisms. Such research has greatly increased our understanding of eye development. These genes function to regulate initial specification of the eye field, migration of retinal precursors, patterning of the retina, neural crest cell biology, and activity of head mesoderm. This review will discuss the discovery of loci using patient data, their investigations in animal models, and the recent advances stemming from animal models that shed new light in patient diagnosis.

[Timing of congenital cataract surgery : Amblyopia versus aphakic glaucoma]

A congenital cataract is a rare disorder, which is associated with a high risk of amblyopia. Ophthalmologists are faced with many diagnostic and surgical challenges in the management of this disease. Older children can undergo primary treatment with an intraocular lens, whereas children younger than 12 months of age usually initially remain aphakic. The most frequent long-term complication of aphakic eyes following congenital cataract surgery in connection with posterior capsulorrhexis and anterior vitrectomy is aphakic glaucoma, which in individual cases can lead to substantial impairment of vision. Many factors have been reported to increase the risk of postoperative glaucoma, including microphthalmos, fetal nuclear cataract, conspicuous family history and associated ocular malformations, such as persistent fetal vasculature (PFV). Cataract surgery during early infancy is well-established to be the most important factor for the formation of postoperative aphakic glaucoma. In individual treatment planning it has to be considered that although younger age at the time of cataract removal can provide better prerequisites for prophylaxis of amblyopia, it also confers a higher risk of development of aphakic glaucoma. Children undergoing congenital cataract surgery have to be regularly monitored given the lifelong risk for postoperative complications, such as aphakic glaucoma.