A condition sometimes described as a “naevus of the choroid” must not be confused with the tumour formation being discussed. It is a melanoma, which appears uniformly grey in colour. It has either a definite or a feathery edge. It shows little or no elevation, but has a tendency to become malignant (Johnston, 1929).

Other ocular changes. The retinal vessels (Schirmer, Yamanaka, Beltmann, Aynsley) and the choroidal vessels (Salus, Steffens, Krause), as seen with the ophthalmoscope, have frequently been described as being dilated and tortuous. The fundi were dark red in colour in the patients of Perera, Padovani and Sturge. Several instances of large tortuous retinal vessels in hydrophthalmic eyes not accompanied by facial naevi have been reported. In Grimsdale's case (1917) the arteries were tortuous and much larger than the veins. Instances of tortuous retinal vessels, particularly in the neighbourhood of the disc on the same side as facial naevi in non-hydrophthalmic patients have been referred to by Collins (1917), Hartridge (1901), Voegele (1925), Yamanaka (1927), Work Dodd (1901) and others. It is not surprising that some of such patients have also a naevoid state of the nasal mucous membrane. The man reported by Collins had recurrent epistaxis. Such cases constitute a link with the syndrome of facial and intra-nasal naevi which is commonly hereditary and is known as Osier's disease. See Goldstein (1936) and McArthur (1937).

Bär (1925) described a case of glaucoma with naevus of the eyeball and numerous tortuous anastomosing retinal veins in the fundus. A clearly defined patch in the retina was found, and Bar considered it to be haemorrhagic in origin. O'Brien and Porter described an unusual pigmented patch near the temporal periphery of the affected eye in their patient. Enlarged choroidal vessels surrounded this area but the neighbouring retinal vessels were reduced in size. These patches, like other retinal anomalies, appear to be most commonly found in the inferior temporal quadrant. Compare anterior dialyses, falciform fold, cysts, and vascular tumours of the retina.