Peripheral retinal nonperfusion using widefield imaging with von Hippel-Lindau disease

Hyper-reflective retinal foci as possible in vivo imaging biomarker of microglia activation in von Hippel-Lindau disease

Purpose

von Hippel-Lindau (VHL) disease is caused by a mutation of the VHL gene and characterized by the development of retinal hemangioblastomas (RH). Current pathophysiologic mechanisms of RH development and progression are still insufficient to predict RH behavior. VHL gene is involved in the cellular response to hypoxia and in many intracellular signaling pathways expressed both in angiogenesis and inflammation. Optical coherence tomography (OCT) allows to identify hyper-reflective retinal foci (HRF) known as aggregates of activated microglial cells as possible in vivo biomarker of local inflammation. The aim of the present study was to investigate the presence of HRF in patients with genetically confirmed VHL disease.

Methods

In this cross-sectional study, patients with VHL underwent complete ophthalmological examination and OCT with HRA + OCT Spectralis. HRF were manually identified and calculated in inner (IR), outer (OR) and full retina. Age-matched healthy subjects were enrolled as controls.

Results

113 eyes of 63 VHL patients and 56 eyes of 28 healthy subjects were evaluated. HRF number was significantly higher in VHL than in controls in IR (28.06 ± 7.50 vs 25.25 ± 6.64, p = 0.042). No difference was observed in OR and in full retina (OR: 7.73 ± 2.59 vs 7.95 ± 2.51, p = 0.599; full retina: 35.79 ± 8.77 vs 33.20 ± 7.47, p = 0.093).

Conclusion

The increase of HRF, which mirror retinal microglial activation, characterizes VHL eyes. The role of activated microglia in the retina of VHL eyes needs to be better investigated, mainly considering local VHL disease manifestations.

Ophthalmological Aspects of von-Hippel-Lindau Syndrome

Background: von Hippel-Lindau (VHL) syndrome is a multisystem neoplastic disorder involving eyes, central nervous system, kidneys, spine, and other tissues. A retinal capillary hemangioma (RCH) is the earliest manifestation of the VHL disease in most cases.Areas covered:This paper aims to provide an up-to-date review of the current literature about von Hippel-Lindau syndrome. Molecular background, systemic and ocular features of the diseases as well as the utility of newer imaging modalities in diagnosis and monitoring of ocular VHL disease have been described. Besides, we have discussed newer treatment modalities and therapeutic targets.Conclusion: Modern imaging technologies like optical coherence tomography and optical coherence tomography angiography are tools of the trade, in making an appropriate diagnosis and monitoring disease activity and response to treatment. Peripheral RCH may be treated using laser photocoagulation in tumors up to 3000 µm. Vascular endothelial growth factor suppression can help in reducing tumor activity and stabilize the tumor size; however, it does not regress the RCH.

Macular Perfusion Impairment in Von Hippel-Lindau Disease Suggests a Generalized Retinal Vessel Alteration

Background: To evaluate macular perfusion in patients with Von Hippel–Lindau (VHL) disease. Methods: VHL patients with or without peripheral retinal hemangioblastomas (RHs) were consecutively enrolled. A group of healthy subjects served as controls. Macular perfusion was analyzed by means of OCT angiography (OCTA) in the superficial vascular plexus (SVP), and in the intermediate (ICP) and deep retinal capillary (DCP) plexuses. The following OCTA parameters were measured: Vessel Area Density (VAD), Vessel Length Fraction (VLF), Vessel Diameter Index (VDI) and Fractal Dimension (FD). Results: Sixty-three VHL patients (113 eyes) and 28 healthy controls (56 eyes) were enrolled. All OCTA quantitative parameters were reduced in VHL patients vs. controls, reaching statistical significance for VAD of the SVP (0.348 ± 0.07 vs. 0.369 ± 0.06, p = 0.0368) and VDI of all plexuses (p < 0.03 for all). No significant differences were detected between eyes without or with peripheral RHs. Conclusions: Macular perfusion is reduced in VHL patients demonstrating retinal vessel changes that are independent of the presence of peripheral RHs. VHL gene mutations disrupt the hypoxia-induced (HIF)/vascular endothelium growth factors (VEGF) pathway and the Notch signaling, both essential for the normal retinal vasculogenesis and angiogenesis. Therefore, an anomalous generalized retinal vascular development may be hypothesized in VHL disease.

Insights into retinal hemangioblastoma using ultra widefield imaging

Purpose:

Retinal hemangioblastomas (RHs) are characteristic of von Hippel-Lindau (VHL) disease. Early diagnosis of retinal lesions may aid in systemic diagnosis. Early identification of VHL is life-saving and also prevents vision loss. Fundus fluorescein angiography (FFA) is a useful tool in the diagnosis and management of RHs. The aim of this study is to report FFA features of RH using ultra-widefield (UWF) imaging.

Methods:

A retrospective cross-sectional study of consecutive patients of RH who underwent UWF FFA at a tertiary eye care center. Images were analyzed and assessed by authors. The main outcome measures were (a) the number and size of RH in each eye and (b) vascular characteristics of the retina. UWF-FFA characteristics in each eye were tabulated. The number of clock hours involved by these characteristics and their correlation with the number and size of RH were analyzed.

Results:

The study evaluated 24 eyes of 13 patients. The mean age was 28.4 years. The median number of RHs in an eye was 3.5 (range 1–16), and the size of RHs varied from 0.1 to 4 disc diameters. Novel UWF-FFA findings noted in this study were the presence of abnormal capillary network in 22 of 24 eyes (91.7%), capillary leakage in 15 of 24 eyes (62.5%), and capillary telangiectasia in 7 of 24 eyes (29.2%). In addition, feeder arterioles and venules showed bulbous projections in 8 of 24 eyes (33.3%).

Conclusion:

The UWF-FFA characteristics of RH, which have not been described before, were identified. These add to our understanding of the pathogenesis of the disease and may pave the way for future therapeutic targets.

Retinal haemangioblastoma associated with peripheral non-perfusion: widefield fluorescein angiography analysis of 41 cases

AIMS

To investigate the association of peripheral retinal non-perfusion with retinal haemangioblastoma.

METHODS

Medical and widefield fluorescein angiography records of patients diagnosed with retinal haemangioblastoma from 1990 to 2018 were reviewed for patient demographics, tumour features, fluorescein angiography features and characteristics of peripheral retinal non-perfusion.

RESULTS

There were 41 eyes of 40 patients with retinal haemangioblastoma imaged by widefield fluorescein angiography during this time period. Of 41 eyes, 14 (34%) had haemangioblastoma-associated peripheral retinal non-perfusion on fluorescein angiography. A comparison of eyes with versus without non-perfusion revealed younger mean age at presentation (28 vs 43 years old, p=0.05), increased prevalence of von Hippel-Lindau (VHL) disease (62% vs 22%, p=0.01), greater mean largest tumour basal diameter (3.7 vs 2.5 mm, p=0.04), greater tumour distance from optic nerve (8.4 vs 1.9 mm, p<0.01) and increased prevalence of vascular leakage from the tumour (86% vs 52%, p=0.03). After mean follow-up of 97 versus 71 months (p=0.52), eyes with non-perfusion were significantly more likely to develop neovascularisation (40% vs 0%, p<0.01) and experience a three-line or greater decrease in visual acuity (60% vs 11%, p<0.01).

CONCLUSION

Peripheral retinal non-perfusion can be associated with retinal haemangioblastoma, and could be more common with larger, more peripheral tumours in younger patients with VHL disease. Eyes with haemangioblastoma-associated peripheral non-perfusion could be more likely to develop neovascularisation and lose visual acuity.