Retinitis pigmentosa without the characteristic pigmentation : a report of two cases / by George M. Gould.

  • Gould, George Milbrey, 1848-1922.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: Retinitis pigmentosa without the characteristic pigmentation : a report of two cases / by George M. Gould. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    and the author inclines to view the balance as cases of retinite jnr/men/airi^ lavvee, either stationary or progres- sive, different cases showing all intermediate stages of nearly absent or typical pigmentation up to the character- teristic retinitis pigmentosa. Assuming, then, that my cases were pathologically and essentially of the same nature as those of Perrin and Huidiez, we have as the nature of the tissue-change a mor- bid cirrhotic process existing in the pigment layer of the retinal periphery, whereby the pigment infiltrates the re- tina in discrete punctate particles, but the infiltration is checked at the external granular layer, not, however, be- fore having injured the retinal structure so as to de.stroy its functions as an intermediate of light sensation and color sensation. At this point the discrete pigment-infiltration becomes ophthalmoscopically visible as a half hidden punctate stippling. If the infiltration-process proceeds to its full extent, the pigment becomes heaped in large moss- like masses, and extends along the course of the obliter- ated capillaries, giving the typical picture of the completed and characteristic retinitis pigmentosa. What starts the morbid process into existence, whether it is congenital or not, what checks it, if it is checked, what is its rate of progress, if progressive—these are questions that remain to be answered. Therapeutics is also incon- ceivable. It should be added, that we may feel absolutely assured that the morbid process is not confined to the ret- inal periphery; the limitations and irregularities of the color-fields of my cases clearly demonstrate that the whole retina is affected, and as my charts show, irregularly so. The limitations are relatively not concentric. But the mi- croscope as yet fails to tell us of the infinitely small local changes that interfere with the responses to certain colors, permit them to others, while still not too extensive to pre- vent the general reaction to white. The indication is, that color-response is interfered with by a slighter degree of the infiltration-process than that occurring at the periph- ery, and one that so far has escaped the microscope. The explanation of color-sensation may result from a closer attention by the microscopist to the difference in tissue change between the periphery and the central part of the field, both in these cases and in normal retinae. More mi- croscope and less theory, might lessen the work of the eter- nal theory-makers as to the nature of color-reactions.