The OphthalmoscopeR. Hardwicke, 1864 - 225 pages |
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Common terms and phrases
accommodation afford amaurosis appear arteries atrophy atropine axis become blood bright cataract centimetres central centre changes chiefly choroidal vessels ciliary Coccius colour concave lens concave mirror convergent convex lens cornea dark degree diagnosis diameter dilatation direction disease distance effect effusion erect image excavation exudations field of vision flame focal length focus fundus fundus oculi glass globe Gräfe hæmorrhage hyperæmia illumination increased inflammation instrument intra-ocular inverted image iridectomy iris latter layer lenses less Liebreich light macula lutea magnified margin membrane millimetres morbid movements myopia necessary nerve disk normal object ocular opacities ophthalmo ophthalmoscope optic disk optic nerve papilla patient perforation periphery pigment placed plane mirror plate portion position posterior present prism produced pupil rays reflected rendered retina retinal vessels sclerotic screw seen side sight sometimes spots stroma surface surgeon tint tissue transparent tube turbidity usually vascular veins visible vitreous body
Popular passages
Page 142 - ... from the size of a lentil to that of a pea, and also by the white flecks already described.
Page 73 - Liebreich for the inverted image, in spite of abundant light and perfect definition, the details of the picture appear to be all in the same plane. The vessels of the retina can be distinguished from those of the choroid by colour and direction, but not by any appreciable difference in their position. The depressions formed by choroidal atrophy or posterior staphyloma, and the elevations from sub-retinal haemorrhage or effusion, present colours which contrast with those of the general field, but...
Page 10 - The problem was threefold : the observed eye must be sufficiently illuminated ; the eye of the observer must be placed in the direction of the emerging rays ; and these must themselves be changed from their convergence, and rendered divergent or parallel.