Handbook of ophthalmology / by C. Schweigger ; translated from the third German edition by Porter Farley.

Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: Handbook of ophthalmology / by C. Schweigger ; translated from the third German edition by Porter Farley. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    547/568 (page 541)
    Listing* designated the symptom as “sichelformiges Flimmer- scotom.” Forsterf proposed the name amaurosis partialis fugax. It should be mentioned, in concluding the subject of homon- ymous hemiopia, that in very rare cases bilateral symmetrical limitations of the visual field, above and below, have been observed, for which an anatomical explanation is yet wanting. If these defects be sharply defined from the normal visual field, and there be no great diminution of central vision, a prognosis may be made similar to that in typical hemiopia. Temporal hemiopic defect is the name given to those limita- tions of the visual field which involve only its outer half on both sides. Still, we do not reckon as such, cases where, as in progressive atrophy of the optic nerve, the defect begins on the temporal side and from there spreads over the entire visual field, but only those which involve simply the temporal half on both sides, and which remain, for some time at least, stationary in this condition. Von GraefeJ remarked that under these relations there are generally symptoms pointing to the existence of a tumor or some cause of pressure at the base of the brain, and the correctness of this view has been confirmed by numerous observations^ Moreover, there occur cases in which the entire course of the disease, or its complete recovery, renders the existence of a tumor exceedingly improbable, and suggests the idea that simple inflam- matory processes at the base of the brain may produce the same effect. Every such cause of disease acting at the median line will, of course, affect most the fasciculi cruciati lying near the median line, both before and behind the chiasm, and accordingly the inner halves of the retime will suffer most. Such processes will not be strictly limited to certain fibrous bundles, but only the median bundles will be first and most seriously affected, while the more lateral fasciculi will be proportionately less affected, so that the defect in the visual field is not sharply defined. The prognosis in temporal defects is generally more unfavorable * Klin. Monatsbl. f. Augenheilk., 1867, pag. 334. -j- Ibid., 1869, pag. 422. J Arch. f. Ophth., B. ii. 2, pag. 287. g Dr. D. E. Muller, Arch. f. Ophth., B. viii. 1, pag. 160; Samisch, Klin. Monatsbl., 1865, pag. 51.