Sir,

Cavernous haemangioma is a rare cause of vitreous haemorrhage. Optical coherence tomography (OCT) helps explain the mechanism.

Case report

An asymptomatic 12-year-old girl with no relevant ophthalmic, medical, or drug history was referred with a lesion in the retina of the right eye. Best-corrected visual acuities were 6/6 OD, 6/5 OS. Anterior segment examination was unremarkable. There was a cluster of discrete dark red vascular saccules with an overlying grey–white epiretinal membrane in the right nasal retina, consistent with a retinal cavernous haemangioma.

Fluorescein angiography demonstrated slow flow through the saccules. Areas of masking within the saccules were due to thrombosis and hyperfluorescent areas within the saccule were due to pooling of fluorescein. Typical fluid levels (see arrow, Figure 1) within the saccules were seen where thrombus and fluid were present.

Figure 1
figure 1

Venous phase of the fluorescein angiogram of the retinal cavernous haemangioma.

Full size image

OCT elegantly images the lesion in cross section (Figure 2) and may explain why spontaneous vitreous haemorrhage can occur in the absence of a vitreous detachment. An overlying epiretinal membrane is imaged as a continuous hyper-reflective signal attached to the saccules and forming bridges between them (see arrow, Figure 2).

Figure 2
figure 2

Optical coherence tomography of the retinal cavernous haemangioma.

Full size image

Comment

Retinal cavernous haemangioma is a rare vascular malformation, it is often unilateral and may present either as an incidental finding or as a cause of vitreous haemorrhage. There may be associated cutaneous lesions and intracranial vascular malformations.1 An autosomal dominant inheritance has been reported, but cases are usually sporadic.2

Histology of cavernous haemangiomas has been reported.3 The ultrastructurally normal vessel wall maintains the blood retinal barrier, which explains the absence of fluorescein leak. The epiretinal membrane is formed by retinal glial cells, which proliferate on the inner retinal surface after gaining access through breaks in the internal limiting membrane.

Vitreous haemorrhage in retinal cavernous haemangioma is recognised in the absence of trauma and vitreous detachment. Histological studies suggested that these cases of vitreous haemorrhage may be due to epiretinal membrane contraction. The OCT identifies points of attachment to the saccule where a contracting epiretinal membrane could exert traction and cause vitreous haemorrhage.