Retinal Capillary Hemangioblastoma: Clinical Spectrum, Imaging Insights, and Treatment Strategies

Retinal capillary hemangioblastoma (RCH) is a benign but potentially vision-threatening vascular tumour of the retina, frequently associated with von Hippel–Lindau (VHL) disease. They may occur sporadically or as multifocal, bilateral lesions in the context of VHL, often serving as the first manifestation of this multisystem disorder. The tumour's pathogenesis involves dysregulated angiogenesis via hypoxia-inducible factor (HIF) pathways, leading to capillary proliferation and stromal recruitment. Clinically, RCHs may present as asymptomatic peripheral lesions or as juxta papillary tumours causing exudation, retinal detachment, and vision loss. Classification based on anatomical location and growth pattern (endophytic, exophytic, sessile) aids in prognostication and treatment planning. Diagnosis relies on multimodal imaging, including fluorescein angiography, optical coherence tomography (OCT), OCT angiography, and rarely indocyanine green angiography. Management is tailored to tumour size, location, and complications. Options range from laser photocoagulation and cryotherapy to photodynamic therapy and intravitreal anti-vascular endothelial growth factor injections. Vitrectomy is reserved for tractional complications. Systemic HIF-2α inhibitors like belzutifan have shown promising results in stabilizing retinal lesions in VHL patients. Accurate differentiation from other vascular tumours such as vasoproliferative tumours, Coats disease, and cavernous hemangiomas is essential. This comprehensive review outlines the pathophysiology, clinical features, genetics, imaging, and evolving treatment strategies for RCH, emphasizing the importance of an early diagnosis and a multidisciplinary approach.