Combined Persistent Fetal Vasculature: A Classification Based on High-Resolution B-Mode Ultrasound and Color Doppler Imaging

Retrospective Analysis of Surgical Outcomes on Axial Length Elongation in Eyes with Posterior and Combined Persistent Fetal Vasculature

This study aims to investigate the outcomes and risk factors associated with poor vision (vision less than counting fingers, 2.0 logMAR, Snellen vision 20/2000) in patients with posterior or combined persistent fetal vasculature (PFV), with or without surgery. We retrospectively reviewed the medical records of patients who were diagnosed with PFV from January 2008 to April 2021. We included 51 eyes of 44 patients who presented with PFV, of which 38 eyes underwent surgical correction (pars plicata/plana vitrectomy, with or without lensectomy, and intraocular lens implantation) at the median age of 6.0 months (range: 0.7 to 82.0). The mean follow-up was 68.8 months ± 38.0 months. The axial length change in the eyes undergoing surgery was significantly higher than the eyes without surgery (p = 0.025). Initial anterior chamber collapse and retinal detachment were associated with poor vision (p = 0.006 and p = 0.002, respectively). In addition, 37% of eyes with posterior or combined PFV had vision better than counting fingers. Surgery for eyes with PFV could result in better eye growth. Visual outcomes remained poor and were associated with the level of macular abnormality. Initial anterior chamber collapse and retinal detachment at presentation were the risk factors for poor visual outcomes. Vitrectomy for selected PFV eyes is valuable and associated with a better cosmetic outcome (better eye growth).

The lens epithelium as a major determinant in the development, maintenance, and regeneration of the crystalline lens

The crystalline lens is a transparent and refractive biconvex structure formed by lens epithelial cells (LECs) and lens fibers. Lens opacity, also known as cataracts, is the leading cause of blindness in the world. LECs are the principal cells of lens throughout human life, exhibiting different physiological properties and functions. During the embryonic stage, LECs proliferate and differentiate into lens fibers, which form the crystalline lens. Genetics and environment are vital factors that influence normal lens development. During maturation, LECs help maintain lens homeostasis through material transport, synthesis and metabolism as well as mitosis and proliferation. If disturbed, this will result in loss of lens transparency. After cataract surgery, the repair potential of LECs is activated and the structure and transparency of the regenerative tissue depends on postoperative microenvironment. This review summarizes recent research advances on the role of LECs in lens development, homeostasis, and regeneration, with a particular focus on the role of cholesterol synthesis (eg., lanosterol synthase) in lens development and homeostasis maintenance, and how the regenerative potential of LECs can be harnessed to develop surgical strategies and improve the outcomes of cataract surgery (Fig. 1). These new insights suggest that LECs are a major determinant of the physiological and pathological state of the lens. Further studies on their molecular biology will offer possibility to explore new approaches for cataract prevention and treatment.

Diagnostic accuracy of Quantitative Colour Doppler Flow imaging in distinguishing Persistent Fetal Vasculature from Retinal Detachment

PURPOSE

Distinguishing posterior persistent fetal vasculature (PFV) from retinal detachment (RD) may be very challenging clinically and ultrasonographically, as they share common morphological features. However, it is crucial, considering their substantially distinct management and treatment. We aimed to assess the relevance of quantitative colour Doppler flow imaging to distinguish PFV from RD in children.

METHODS

This retrospective bi-centre study included 66 children (30 females and 36 males, mean age: 244 ± 257 days) with a clinically suspected diagnosis of RD or posterior PFV. All children underwent systematic and standardized conventional ultrasonography and colour Doppler flow imaging under general anaesthesia with a qualitative and quantitative analysis of the retrolental tissue's vascularization. Peak systolic velocity, end-diastolic velocity and resistive index were recorded for analysis. Whenever available, surgical findings were deemed gold standard for diagnosis. A Mann-Whitney U-test was used to compare quantitative colour Doppler flow imaging data.

RESULTS

Peak systolic velocity and end-diastolic velocity were significantly lower in children with PFV versus RD: 2.7 (IQR: 0.5) versus 5.1 (IQR: 2.8), p < 0.001, and 0.0 (IQR: 0.0) versus 2.0 (IQR: 1.2), p < 0.001, respectively. Resistive index was significantly higher in children with PFV versus RD: 1 (IQR: 0) versus 0.6 (IQR: 0.1), p < 0.001. Area under curves (AUCs) were of 0.94, 0.99 and 1, respectively. No differences between PFV and RD were observed on structural ultrasound or qualitative analysis of colour Doppler.

CONCLUSION

Quantitative colour Doppler flow imaging has an excellent accuracy in distinguishing PFV from RD in children. It may help to improve management and treatment.

Persistent vasa hyaloidea propria/retinae in familial exudative vitreoretinopathy

The vasa hyaloidea propria, a component of the fetal hyaloidal vasculature, is characterized by multiple persistent fetal vasculatures branching into the vitreous. We present a 4-month-old girl with stage 4 familial exudative vitreoretinopathy, with multiple ectopic retinal vessels extending into the vitreous, confirmed with fluorescein angiography, which was consistent with persistent vasa hyaloidea propia/retinae making contact with the retina. The patient underwent vitreoretinal surgery to address the retinal detachment, during which the patent stalks of the persistent vasa hyaloidea propia/retinae were transected.

Surgical outcomes of cataract surgery in anterior and combined persistent fetal vasculature using a novel surgical technique: a single center, prospective study

PURPOSE

To study the complications and surgical outcomes of cataract surgery in patients of persistent fetal vasculature (PFV) with cataract.

METHODS

In this prospective study, phacoaspiration with/without intraocular lens implantation (IOL) was done in 20 children (mean age 14.2 months) with unilateral cataract with anterior (n = 6) or combined (n = 14) PFV. The rentrolental vascularized membrane was cauterized and dissected circumferentially, followed by cauterization and resection of the PFV stalk. The outcome measures included fixation preference using the CSM (central, steady, maintained) method and intraoperative and postoperative complications in an 18-month follow-up. The difference in outcomes of anterior and combined PFV, as well as aphakic and pseudophakic eyes, was studied.

RESULTS

CSM fixation was seen in 16 patients after 18 months. The intraocular lens was implanted in 16 eyes and 4 eyes with combined PFV were left aphakic. None of our patients had intraoperative bleeding. Visual axis obscuration was the major complication seen, requiring membranectomy in 8 children. Pupilloplasty was required with membranectomy in one eye. None of our patients developed glaucoma or retinal detachment.

CONCLUSION

Timely surgical intervention and aggressive amblyopia therapy led to good visual results in our study. Poor prognosis was seen in combined PFV, aphakia, and microphthalmia.

Cataract management in children: a review of the literature and current practice across five large UK centres

Congenital and childhood cataracts are uncommon but regularly seen in the clinics of most paediatric ophthalmology teams in the UK. They are often associated with profound visual loss and a large proportion have a genetic aetiology, some with significant extra-ocular comorbidities. Optimal diagnosis and treatment typically require close collaboration within multidisciplinary teams. Surgery remains the mainstay of treatment. A variety of surgical techniques, timings of intervention and options for optical correction have been advocated making management seem complex for those seeing affected children infrequently. This paper summarises the proceedings of two recent RCOphth paediatric cataract study days, provides a literature review and describes the current UK 'state of play' in the management of paediatric cataracts.

[Asteroid hyalosis]

The article analyzes existing information on clinical and experimental studies of vitreous changes in asteroid hyalosis, historical aspects of how this condition was studied over the past hundred years, its occurrence and pathogenesis. Results of various studies were used to evaluate current understanding of the forms and elemental composition of phospholipid mineral sedimentation on vitreous structures and methods of its examination. The problem of intravital assessment of the condition of vitreous body was analyzed, and a method was suggested for studying the macrostructure of hyaloid tracts and the state of the vitreous body by means of digital ultrasound in patients with asteroid hyalosis.

In vivo detecting mouse persistent hyperplastic primary vitreous by Spectralis Optical Coherence Tomography

To identify imaging characteristics of mouse persistent hyperplastic primary vitreous (PHPV) by Spectralis Optical Coherence Tomography (OCT), as well as to assess and compare the sensitivity and precision of OCT with color photography (CP) and Fundus Fluorescein Angiography (FFA) imaging in detecting mouse PHPV. Notch4^-/- C57BL/6J mice (224 eyes) aged from 3 months to 7 months were examined in this study. CP, FFA and OCT imaging were utilized to examine vitreous cavity and retina of mouse eyes. Horizontal and radial OCT scan volume was centered on the optic nerve head. Hematoxylin and eosin (H&E) staining was performed to validate PHPV. For color photography and FFA imaging, retrolental irregular fibrovascular membrane-like tissues were found in 33 eyes with/without blood vessels in vitreous cavity. Among them, 31 eyes were visualized with lateral and oblique linear hyperreflective opacities in vitreous cavity using Spectralis OCT. Position of PHPV in posterior segment of eyes was also measured via OCT. Mouse PHPV was validated by H&E staining. Typical hyperreflective opacities in vitreous cavity were detected in PHPV mouse using Spectralis OCT. Spectralis OCT imaging can effectively detect mouse PHPV as color photography and FFA.

Persistent fetal vasculature presenting with axial elongation and platyphakia

Leukocoria in children should always raise the concern for retinoblastoma. However, a variety of non-neoplastic conditions can also present with leukocoria, including persistent fetal vasculature (PFV), a nonhereditary, congenital anomaly caused by a failure of the fetal intraocular vasculature to regress during development. Classically PFV presents with features that make it easily distinguishable from retinoblastoma, including microphthalmia, retrolental fibrovascular membrane, central dragging of ciliary processes, and cataract. We present an atypical case of PFV in a 9-month-old boy who presented with the unusual features of axial myopia and platyphakia.

Innovations in pediatric cataract surgery

Advances in technology have made surgery in children safer and faster. The management of pediatric cataract has made rapid progress in the past decade with the availability of safer anesthesia, newer technique's, more predictable intraocular lens (IOL) power calculation, a better understanding of neurobiology, genetics, amblyopia management, improved IOL designs for preventing visual axis opacification, and adjuvant postoperative care. Modern vitrectomy machines with minimally invasive instruments, radiofrequency, diathermy, and plasma blades help immensely in complicated cases. Preoperative evaluation with ultrasound biomicroscopy and optical coherence tomography (OCT) allows better planning of surgical procedure. The future holds good for stem cell research, customized OCT, and Zepto (precision pulse capsulotomy).