Figure 1. A round yellow-orange retinal lesion is visible in the superotemporal periphery of the left eye. There are dilated retinal vessels entering and exiting it.
A 24-year-old male was referred by another ophthalmologist with an interesting lesion in his left eye.
An asymptomatic 24-year-old man was referred by another ophthalmologist after an incidental finding of a fundus lesion in his left eye by his optometrist. The patient was healthy and had no family history of ocular disease.
Visual acuities were 6/6 in both eyes, with normal intraocular pressures. Anterior segments were normal. In the left eye there was a 5mm diameter yellow-orange round raised retinal lesion in the superotemporal periphery with dilated retinal vessels entering and exiting it (Figure 1). There were no signs of exudation and the right fundus was normal.
The differential diagnosis for a retinal vascular lesion includes:
- Vasoproliferative tumour
- Retinal capillary haemangioblastoma
- Vortex varix
Additional history, examination and investigations
The patient’s blood pressure was recorded at 131/72mmHg. Optical coherence tomography of his macula was normal (Figure 2). Wide-view fluorescein angiography showed a vascularised lesion with feeding retinal arteriole and draining venule (Figure 3). The patient’s immediate family were examined and no fundus lesions were detected. Full blood count, 24-hour urinary catecholamines, MRI/MRA brain and spine, MRI/MRA abdomen were all reported as normal. CT chest showed a possible vascular lesion in the right lower lobe and repeat imaging was advised.
Figure 2. Optical Coherence Tomography of the left macula is normal.
Figure 3. Fluorescein angiography of the left fundus shows early hyperfluorescence of the vascularized lesion with feeding retinal arteriole and draining venule.
Retinal capillary haemangioblastoma.
Given the asymptomatic nature of the lesion, its lack of exudation and the fact that as yet no diagnosis of von-Hippel Lindau syndrome has been made, the lesion is currently being observed.
Retinal capillary haemangioblastomas (RCH) are circumscribed, orange-red vascular tumours of the retina with characteristic dilated feeding retinal arteriole and draining venule. They are most commonly located in the retinal periphery, especially superotemporally, although they can also occur at the optic disc (juxtapapillary RCH).(1) The mean age of diagnosis is 25 years in patients with von Hippel-Lindau disease but older (mean of 48 years) in patients with isolated disease.(2) One third of patients have multiple lesions and half have bilateral involvement.#references The differential diagnosis includes Coats Disease, vasoproliferative tumour, retinal arteriolar macroaneurysm, racemose hemangioma and retinal cavernous hemangioma. Fluorescein angiography is useful in assisting with diagnosis, confirming the vascular nature of these tumours.
The most common complication is lipid exudation, which occurs in a quarter of cases.(1) This can start locally around the tumour but extend posteriorly causing a macular star with intra- and subretinal fluid affecting vision. Vision can also be affected by tractional retinal detachment. It is rare for retinal or vitreous haemorrhage to occur.
Retinal capillary haemangioblastomas can be isolated or associated with von Hippel-Lindau (VHL) disease. VHL is an autosomal dominantly inherited phakomatosis due to a mutation of the VHL gene on chromosome 3p25-26. The most common manifestation of VHL is RCH, which occurs in 49-85% of patients.(1) Conversely, the presence of an isolated RCH predicts VHL to be 30-46%.(3) Extraocular involvement in VHL can include haemangiomas of the central nervous system (brain especially cerebellum and spinal cord), cysts of the kidneys, adrenal glands, pancreas, inner ear, epididymis and broad ligament and tumours of the kidneys, adrenal glands (phaeochromocytoma) and pancreas. Diagnosis of VHL can be made by presence of:
- Greater than one RCH
- RCH with other systemic manifestations of VHL
- RCH with a family history of VHL
Small, isolated RCHs which are not associated with exudation or threatening vision can be monitored closely. Larger lesions and lesions associated with VHL are best treated, since they have a propensity to grow and affect vision via lipid exudation. The most common options for treatment include argon laser photocoagulation for more posterior tumours and cryotherapy for large anterior tumours associated with subretinal fluid. If laser is considered, treatment of the feeder vessel first before obliterating the tumour itself and/or draining venule may reduce the chance of haemorrhage. Often more than one session of laser or cryotherapy is required. Photodynamic therapy may be considered, especially for juxtapapillary tumours affecting vision. Severe cases associated with tractional retinal detachment may require vitrectomy surgery.
TAKE HOME POINTS
- Retinal capillary haemangioblastoma (RCH) is a rare vascular tumour of the retina characterized by a vascular mass with feeding retinal arteriole and draining venule.
- Retinal capillary haemangioblastoma can be isolated or associated with von Hippel-Lindau Disease (VHL).
- Von Hippel-Lindau Disease can be diagnosed if there is more than one RCH, there are haemangioblastomas in the rest of the body or there is a family history of von Hippel Lindau Syndrome.
- Small, isolated lesions of RCH do not always require treatment if they are asymptomatic and not threatening vision. In the setting of VHL, treatment of RCHs are usually indicated as the lesions tend to grow and threaten vision by exudation. Treatment usually involves argon laser photocoagulation and/or cryotherapy.