Text-book of ophthalmology . s entirely opaque, thelenticular mass grows more fluid in proportion as it keeps on breaking upinto smaller and smaller parts. If this process goes on in a young person,in whom there is no hard nucleus in the lens, the latter becomes liquefiedthrough and through, so that the lens consists of a milky fluid (cataractafluida sive lactea). If this metamorphosis affects an old lens, the nucleus,which has failed to become opaque, also escapes disintegration, and sinksunder the form of a heavy compact mass to the bottom of the liquefied cor-tex. The cataract has then a ho
Text-book of ophthalmology . s entirely opaque, thelenticular mass grows more fluid in proportion as it keeps on breaking upinto smaller and smaller parts. If this process goes on in a young person,in whom there is no hard nucleus in the lens, the latter becomes liquefiedthrough and through, so that the lens consists of a milky fluid (cataractafluida sive lactea). If this metamorphosis affects an old lens, the nucleus,which has failed to become opaque, also escapes disintegration, and sinksunder the form of a heavy compact mass to the bottom of the liquefied cor-tex. The cataract has then a homogeneous white appearance, correspond-ing to the milky cortex, and in its lower portion presents a brownish shad-ing, which is bounded above by a semicircular line, and which represents theupper half of the dark nucleus. As the latter alters its position with themovements of the head, the brownish shadow can also be seen to change itsplace. This form of cataract is known as Morgagnian cataract (cataractaMorgagni; Fig. 237).. 542 TEXT-BOOK OF OPHTHALMOLOGY A liquefied lens, however, does not remain permanently unaltered, butinspissation of the fluid occurs later on through the gradual loss of water,the disintegrated lens masses being at the same time in part resorbed. Inthis way the lens constantly diminishes in volume until, in cases in whichno nucleus has been present, it is transformed into a thin, transparent mem-brane (cataracta membranacea). In children, in whom resorption is carriedespecially far, the opaque lenticular masses disappear altogether in two layers of the lens capsule, which has remained transparent, comeinto apposition, and thus there are formed perfectly transparent spots in theopaque lens, recognizable by reflected light as black gaps in the whitepupil. The child begins to see again, a sort of spontaneous cure of the cata-ract having occurred. When a hypermature cataract has lasted a long time, changes set inwhich lead to complications: (a) Chol
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