Retinal hemorrhage thresholds for Q-switched neodymium-Yag laser exposures

Journal Article · Tue Jul 01 04:00:00 EDT 1986 · Invest. Ophthalmol. Visual Sci.; (United States)

OSTI ID:5113932

Blankenstein, M F; Zuclich, J; Allen, R G; Davis, H; Thomas, S J; Harrison, R F

Thresholds for retinal vitreal and contained hemorrhages were determined for 1064 nm laser light at 30-nsec and 4-nsec pulsewidths. Rhesus monkeys received graded exposures from a neodymium-yag laser onto either the macular or extramacular region of the retina. Contained hemorrhages appeared as concentric ring structures with white punctate centers. The vitreal hemorrhage was characterized by the presence of choroidal blood in the vitreal chamber at the exposure site. The 30-nsec contained hemorrhage threshold (ED50) was 1.7 mJ on the macula and 2.1 mJ for an extramacular exposure. The 30-nsec vitreal hemorrhage macular threshold was 2.3 mJ, and the extramacular threshold was 6.6 mJ. The threshold for the 4-nsec pulsewidths to produce a hemorrhage (vitreal or contained) on the retina (macula or extramacular) was 340 microJ.

• OSTI ID: 5113932
• Journal Information: Invest. Ophthalmol. Visual Sci.; (United States), Journal Name: Invest. Ophthalmol. Visual Sci.; (United States) Vol. 7; ISSN IOVSD
• Country of Publication: United States
• Language: English

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