After having a stroke or spinal cord injury, it is vital to ensure that the nervous system is still functioning properly. Signs that the nervous system has been impacted include delayed movements, difficulty with speech, and paralysis of certain muscles. Horner Syndrome, a condition that affects the neural pathways of the eye and face, is often caused by damage to the nervous system.
Physical manifestations of Horner Syndrome include uneven pupils, a sunken appearance of the eye that is affected, and drooping of the eyelid. Specifically, one pupil will look much smaller than the other, even in altered lighting.
A patient with Horner Syndrome demonstrating miosis, a constricted and uneven pupil. Additionally, the affected eyelid is drooping.
The cause of Horner Syndrome is deeply correlated with the activity of certain neurons that provide signals to the head, neck, and face. Three significant types of neurons that play a role in Horner Syndrome are first-order neurons, second-order neurons, and third-order neurons. These electrical messengers differ in the regions that they cover to transmit information.
For instance, first-order neurons originate from the hypothalamus, which is located at the base of the brain. They branch out to the upper region of the spinal cord, signifying that damage to this region in the form of a stroke or neck trauma may be a cause of Horner Syndrome.
Second-order neurons extend from the spinal cord and cover the upper section of the chest, as well as the side of the neck. These neurons may be impacted by traumatic injuries to the chest or lungs, which could ultimately lead to the development of Horner Syndrome.
Third-order neurons transmit information along the sides of the neck, leading to the facial area and eyelid muscles. Thus, damage to the arteries or veins within the neck may be associated with Horner Syndrome.
In children, Horner Syndrome may be caused by issues prior to or during birth. For instance, if there is injury to the neck or spinal cord during delivery of the child, they may develop the condition. Additionally, if there are obstructions in the chest or brain region, Horner Syndrome may occur later in life due to nervous system damage.
It is important to acknowledge that Horner Syndrome can be developed without a specific cause. Even though most cases of Horner Syndrome can be traced back to nervous system damage, rare cases may have no identifiable cause. Horner Syndrome does not have a current treatment, but individualized treatment for the underlying nervous system damage may assist in rehabilitation of the nerve supply.
References:
https://www.mayoclinic.org/diseases-conditions/horner-syndrome/symptoms-causes/syc-20373547