Related Experiment Video
Updated: Mar 2, 2026

Rodent Model of Masseter Volumetric Muscle Loss for Studying Bioengineering Materials
Published on: May 31, 2024
Acute visual loss after botulinum toxin A injection in the masseter muscle
1Department of Ophthalmology, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 700-721, South Korea. byjun424@hotmail.com.
Purpose:
Acute visual loss after facial injection of cosmetic materials is rarely reported. In this study, we report one patient who developed acute visual loss after an injection of botulinum toxin A for esthetic purposes.
Methods:
A 43-year-old Korean woman presented with a decrease in visual acuity to 20/800 after an injection of botulinum toxin A in the masseter muscle. The visual field testing showed an inferior altitudinal defect, and fluorescein angiography revealed a delayed arm-retinal circulation time.
Results:
After intravenous and oral prednisolone was administered, the patient's visual acuity gradually improved. Two months after the botulinum toxin A injection, the visual acuity had almost returned to baseline, with a remaining paracentral scotoma.
Conclusions:
This is the first case of acute visual loss following an injection of botulinum toxin A in a facial lesion. This case emphasizes that the potential risks of botulinum toxin A injection should be considered, and the procedure should be performed delicately.
Related Concept Videos
Myasthenia Gravis: Overview and Treatment
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which...
Directly Acting Muscle Relaxants: Dantrolene and Botulinum Toxin
The binding of dantrolene to the RYR1...
Disorders of the Skeletal Muscle
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
Chemical Synapses
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
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...
Myasthenia Gravis: Diagnostic Tests
The edrophonium test is a diagnostic tool for myasthenia gravis. It involves...

