Consequence of ocular sympathetic nerve paralysis, Claude Bernard-Horner syndrome manifests itself by ptosis of the upper eyelid, narrowing of the pupil and absence of sweating on the affected side of the face. It can be a sign of an underlying pathology.

Definition

Claude Bernard-Horner syndrome is a neurological syndrome affecting part of the face, and in particular an eye.

Causes

Claude Bernard-Horner syndrome can occur spontaneously (primary form), or be the consequence of a lesion of the fibers of the sympathetic nervous system innervating the orbit. Some of them descend along the spinal cord, come out to emerge in the thorax and then up along the neck to the eye. Also, an injury or compression on the path of these nerve fibers can lead to Claude Bernard-Horner syndrome. This lesion can be central (in the brain) or peripheral (in a cervical sympathetic trunk). That is :

• carotid dissection;
• a cerebral vascular accident ;
• cervical lymphadenopathy (lymph nodes in the neck);
• a tumor, especially of the lung, which compresses the sympathetic nerve;
• cervical spine surgery (rare).

Note that there are also congenital forms of Claude Bernard-Horner syndrome.

Diagnostic

Confirmation of the diagnosis of Claude-Bernard-Horner syndrome is based on the installation of eye drops of cocaine (4 or 10%) or apraclonidine (0,5 or 1%). Cocaine is an indirect sympathomometic: it causes dilation of the pupil. In Claude Bernard-Horner syndrome, the affected pupil will not dilate as well as the other pupil. Apraclonidine, for its part, has an action on certain receptors for pupillary dilation. In the event of Claude Bernard-Horner syndrome, it will cause dilation of the pupil.

If the diagnosis of Claude Bernard-Horner syndrome is confirmed, 48 hours later an ophthalmic test using hydroxyamphetamine drops can be performed to localize the lesion, pre- or postganglionic.

The Claude-Bernard-Horner syndrome triad, unilateral pain in the head, face and neck and, a few hours or days later, ipspheric or ipsilateral retinal ischemia suggests carotid dissection. The cervical color doppler ultrasound is then the first-line examination.

Depending on the clinical context, an MRI of the brain, spinal cord, thorax or neck may be prescribed in order to locate the lesion, and to detect the possible pathology at the origin of the syndrome.

Persons concerned

Claude Bernard-Horner syndrome can occur at any age.

The symptoms of Claude Bernard-Horner syndrome appear on the side of the face where the nerve fibers are damaged. They combine:

• upper eyelid ptosis: the upper eyelid falls out due to paralysis of the smooth muscle fibers associated with the levator of the upper eyelid;
• a construction of the pupil (miosis), due to paralysis of the dilator muscle of the pupil. The pupil is narrowed, but generally without impact on vision, or rarely on night vision in some patients;
• decreased sweating on the affected side of the face, sometimes with episodes of redness.

To treat Claude Bernard-Horner syndrome, it is a question of treating the cause at the origin of the Claude Bernard-Horner syndrome.