Macular hemorrhage after laser exposure and cannabinoid intake during a disco party

Dutch-belted 1 to 2.5 kg anesthetized rabbits were exposed to either xenon or argon laser light administered in a broad band, designed to cover large areas of the retina. For laser exposure, the pupil was dilated with atropine sulfate 1% and pheny lephrine 10%. All of the laser generated power was within a band centered at 5145.0 Anstroms. Established threshold for 4 hour exposures to laser irradiation are in the order of 25-35 microwatts/cm2. Animals examined for ultrastructural changes received 4 hour threshold doses. These animals exhibited ERG, opthalmascopic, and histological changes consistent with threshold damage.One month following exposure the rabbits were killed with pentobarbitol. The eyes were immediately enucleated and dissected while bathed in 3% phosphate buffered gluteraldehyde.

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Fading of the diaminobenzidine reaction product in the confocal scanning laser microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152707 ◽

1989 ◽

Vol 47 ◽

pp. 146-147

Author(s):

JS Deitch ◽

KL Smith ◽

JW Swann ◽

JN Turner

Keyword(s):

Pyramidal Neurons ◽

Light And Electron Microscopy ◽

Scanning Laser ◽

Laser Exposure ◽

Confocal Scanning Laser Microscope ◽

Fluorescent Markers ◽

Before And After ◽

Staining Protocol ◽

Confocal Scanning ◽

Confocal Scanning Laser

Neurons labeled with horseradish peroxidase and reacted with diaminobenzidine (DAB) can be imaged using a confocal scanning laser microscope (CSLM) in the reflection mode. In contrast to fluorescent markers, the DAB reaction product is thought to be stable and can be observed by both light and electron microscopy. We have investigated the sensitivity of the DAB reaction product to laser irradiation, and present the spectrophotometric properties of DAB before and after exposure in the CSLM.Pyramidal neurons in slices of rat hippocampus were injected with biocytin (a biotin-lysine complex), fixed overnight in 4% paraformaldehyde, and vibratome sectioned at 75 μm. Biocytin was detected with avidin-HRP (1:200) in 0.5% Triton X-100, incubated in DAB (0.5 mg/ml) with or without 0.04% nickel ammonium sulfate (Ni), dehydrated, and imaged in a Bio Rad MRC-500 CSLM with an argon ion laser (488 and 514 nm). Spectrophotometric measurements of the soma were made on a Zeiss microspectrophotometer, as a function of laser exposure (100-1000 scans) and staining protocol.

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Research on ganglion cell responses after laser exposure of the retina

PsycEXTRA Dataset ◽

10.1037/e539192008-001 ◽

1980 ◽

Cited By ~ 1

Author(s):

Myron L. Wolbarsht

Keyword(s):

Ganglion Cell ◽

Laser Exposure ◽

Cell Responses

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Immediate post partum macular subretinal bleeding in a highly myopic patient: a case report

BMC Ophthalmology ◽

10.1186/s12886-021-01814-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Karen Bitton ◽

J.-L. Bacquet ◽

F. Amoroso ◽

S. Mrejen ◽

M. Paques ◽

...

Keyword(s):

Valsalva Maneuver ◽

Post Partum ◽

Pathologic Myopia ◽

Pathological Myopia ◽

Case Presentation ◽

Sudden Loss ◽

Corrected Visual Acuity ◽

First Case ◽

History Of ◽

Macular Hemorrhage

Abstract Background Pathologic myopia is a major cause of visual impairment and blindness. Case presentation We report a case of an immediate post partum macular subretinal bleeding observed in a highly myopic patient. A 30-years-old woman presented two days after childbirth for sudden loss of vision in her right eye. Multimodal imaging showed macular hemorrhage masking a subtle yellowish linear lesion corresponding to lacker crack. Due to the lack of evidence for choroidal neovascularization, a simple clinical and imaging monitoring was recommended. Six weeks later, we noted an improvement in her best-corrected visual acuity and a decreased in size of the macular hemorrhage. Conclusions This is the first case reporting a macular subretinal bleeding on macular lacquer cracks in a highly myopic patient in immediate post partum. Valsalva maneuver associated with vaginal delivery could explain the occurrence of the hemorrhage associated with lacquer crack. However, natural history of pathological myopia could not be excluded.

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