Summary
Using our optical attachment to the photocoagulator of Zeiss-Oberkochen, enabling to work with the Goldmann 3 mirror contact glass, an effort has been made to reduce both pulse energy and damage to the choroid and nerve fiber layer. This has been found to be possible by electronic control of exposure time in combination with measurement of radiation dose. Small, not overdosed lesions, which in most respects resemble those generated by low-power pulsed lasers, can be obtained by superposing the cathode hot spot of the xenon arc with its mirror image, using small field stops and an exposure time of, typically, 0.1 sec. No modification of the electrical equipment of the coagulator is necessary. The lesions produced in this way on rabbits are characterized by a relatively rapid resorption of edema and abundant pigment proliferation. The choroid and nerve fiber layer are not affected.
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This investigation was supported by a Grant to the University of Bern, Number NB-03638-05 from NINDB, National Institutes of Health, Bethesda, Maryland, USA.
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Fankhauser, F., Lotmar, W. & Roulier, A. Reduction of energy in photocoagulation with the Zeiss-Oberkochen xenon-arc apparatus. Albrecht von Graefes Arch. Klin. Ophthalmol. 182, 177–188 (1971). https://doi.org/10.1007/BF00414640
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DOI: https://doi.org/10.1007/BF00414640