Related Experiment Video
Updated: Jan 24, 2026

An Optic Nerve Crush Injury Murine Model to Study Retinal Ganglion Cell Survival
Published on: April 25, 2011
Association between Chagas disease and changes in the optic nerve and retinal nerve fiber layer
Flávia da Silva Villas-Bôas1, Alexandre Campelo Ramiro1, Thaís de Santana Machado Martins1
1Instituto Brasileiro de Oftalmologia e Prevenção da Cegueira, Salvador, BA, Brazil.
Purpose:
To test the hypothesis that Chagas disease predisposes to optic nerve and retinal nerve fiber layer alterations.
Methods:
We conducted a cross-sectional study including 41 patients diagnosed with Chagas disease and 41 controls, paired by sex and age. The patients underwent ophthalmologic examinations, including intraocular pressure measurements, optic nerve and retinal nerve fiber layer screening with retinography, optical coherence tomography, and standard automated perimetry.
Results:
All of the patients with Chagas disease had a recent cardiologic study; 15 (36.6%) had heart failure, 14 (34.1%) had cardiac form without left ventricular dysfunction, and 12 (29.3%) had indeterminate form. Optic nerve/retinal nerve fiber layer alterations were observed in 24 patients (58.5%) in the Chagas disease group and 7 controls (17.1%) (p£0.01). Among these, optic nerve pallor, optic nerve alterations suggestive of glaucoma, notch, peripapillary hemorrhage, and localized retinal nerve fiber layer defect were detected. Alterations were more prominent in patients with Chagas disease and heart failure (11 patients), although they also occurred in those with Chagas disease without left ventricular dysfunction (7 patients) and those with indeterminate form (6 patients). Optical coherence tomography showed that themean of the average retinal nerve fiber layer thickness measured 89 ± 9.7 mm, and the mean of retinal nerve fiber layer superior and inferior thickness measured 109 ± 17.5 and 113 ± 16.8 mm, respectively were lower in patients with Chagas disease. In controls, these values were 94 ± 10.6 (p=0.02); 117 ± 18.1 (p=0.04), and 122 ± 18.4 mm (p=0.03).
Conclusion:
Changes in optic nerve/ retinal nerve fiber layer were more prevalent in patients with Chagas disease.
Related Concept Videos
Local Anesthetics: Differential Sensitivity of Nerve Fibers
Nerve Supply of the GI Tract
The enteric nervous system consists of two major plexuses: the myenteric plexus (Auerbach's plexus) and the submucosal plexus (Meissner's plexus). These plexuses are located within the layers of...
Spinal Nerves: Plexus II
The Lumbar Plexus
The lumbar plexus is situated within the lumbar region of the back and is primarily formed by the first four lumbar spinal nerves (L1 to L4). This plexus extends its branches into several nerves, including the...
Cranial Nerves: Types Part I
Olfactory Nerve (Cranial Nerve I)
The olfactory nerve, or cranial nerve I, is unique as it is purely sensory and dedicated to the sense of smell. This nerve originates in the olfactory epithelium of the...
Cranial Nerves: Types Part II
Facial Nerve (Cranial Nerve VII)
Cranial nerve VII, or the facial nerve,...
Spinal Nerves: Anatomy
There are 31 bilateral pairs of spinal nerves, each emerging from the spinal cord through the intervertebral foramina—openings between adjacent vertebrae. These nerves are...

