Ophthalmology

The signs of sclerosis and their pathology are discussed on clinical grounds. Universally the transparency of the vessel wall is impaired, the light reflex on the vessel is dotted, and the artery loses its rose colour and resembles copper wire. An early sign of sclerosis is the appearance of white lines along the vessels at their crossings. These are all common appearances in all types of sclerosis, whether involutionary or hyperpietic in type. In the more severe types of sclerosis the colour of the artery becomes whiter and resembles silver wire, the lumen is irregular, as evidenced by alteration in calibre of the vessel at different points, the tortuosity of the vessel increases, and the veins are nipped at the crossings. There is a detailed study of the different appearances at the vessel crossings : the veins may be depressed only, but in many cases they show deflection either away from the disc or towards the disc. The crushing at the crossings may lead to dilatation of the vein on the peripheral side of the artery. These changes at the crossings he considers to be due to proliferative changes in the perivascular sheath: the sheaths of vein and artery adhering to each other