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Updated: Feb 1, 2026

Three-dimensional Imaging and Analysis of Mitochondria within Human Intraepidermal Nerve Fibers
Published on: September 29, 2017
Retinal nerve fiber layer analysis in cocaine users
Henrique Gemelli1, Thiago M Fidalgo2, Carolina P B Gracitelli3
1Department of Ophthalmology, Hospital do Servidor Público Estadual Francisco Morato de Oliveira, São Paulo, Brazil.
Abstract:
Cocaine is a well-known factor of tissue ischemia and may be related to thinning of the inner retinal layers. The present study aimed to evaluate and determine whether cocaine users show retinal nerve fiber layer (RNFL) thinning by means of spectral-domain optical coherence tomography. A group of 17 cocaine users and 18 non-users were recruited for complete ophthalmologic examination. Spectral domain optical coherence tomography (Cirrus OCT) was used to evaluate peripapillary RNFL and macular thickness. The average RNFL measurement in the cocaine users group was significantly thinner compared to the control group. Subjects in the cocaine users group showed significant thinning in the nasal, superior and inferior quadrant. There were no significant differences in macular thickness or in the temporal quadrant between the two groups. This study supports further research with larger sample sizes to precisely determine the effect of cocaine on the RNFL.
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