Why does horner syndrome cause ptosis

The examination revealed right miosis with preserved pupillary light reflex and right ptosis; the patient reported diplopia with extreme right gaze positions. The neurological and general examination revealed no other relevant findings. A blood analysis detected no remarkable alterations. A brain CT scan and a CT angiography study showed no parenchymal alterations and revealed reduced contrast flow in the extracranial section of the right internal carotid artery after the bifurcation , with occlusion of the arterial lumen Fig.

Brain MRI and MRI angiography findings suggested right internal carotid artery dissection at the cervical level, associated with a lack of blood flow from the carotid canal to the venous sinus on time-of-flight sequences Fig. The patient was diagnosed with Horner syndrome and headache secondary to traumatic right internal carotid artery dissection, and was discharged with oral anticoagulants and conventional analgesics.

After several weeks of rest, and resuming work and daily activities, including exercise, he became concerned by his symptoms and sent us a photograph of himself Fig. He presented changes in facial skin colouration after exercise: the left side of his face was flushed and sweaty, whereas the right side was pale, showing anhidrosis.

A 3-month follow-up examination revealed clinical improvements, with mild right ptosis and miosis persisting. Additional MRI and MRI angiography studies revealed no alterations; acenocoumarol was switched for acetylsalicylic acid.

A CT angiography showing reduced blood flow in the right internal carotid artery at the level of the cervical spine. B MRI angiography time-of-flight sequence showing reduced blood flow in the same artery this sequence was taken at a higher level than the CT angiography sequence and a false lumen in the medial region. Photograph sent by the patient after exercise, showing anhidrosis and pallor on the right side of his face, ipsilateral to carotid artery dissection, and flushing and sweating on the left side.

Horner syndrome is caused by disruption of sympathetic nervous system fibres. The first-order neuron emerges from the hypothalamus and descends through the brainstem to the spinal cord, where it synapses in the Clarke column, at the C8-T1 level.

The second-order neuron exits the spinal cord via the T1 nerve root, ascending through the cervical chain ganglia and synapsing in the superior cervical ganglion C1-C2.

The third-order postganglionic neuron travels along the carotid artery to the iris dilator muscle. Insufficient evidence is available to confirm that anticoagulants are more effective than antiplatelets.

We present the case of a patient with rare though characteristic imaging signs of cervical sympathetic chain involvement. The association between anhidrosis or hypohidrosis and skin colouration changes is a typical sign of the disease that helps locate the lesions to the cervical sympathetic chain.

We wish to express our sincere thanks to our patient for consenting to the publication of his case and images; this study would have not been possible without his cooperation.. ISSN: Previous article Next article. Issue 2. Pages March More article options.

Letter to the Editor. The relevance of anhidrosis in Horner syndrome: analysis of an image. Download PDF. Vicente-Pascual , C. Montejo , A. Corresponding author. This item has received. Under a Creative Commons license. Article information. Full Text. Figure 1. Figure 2. We wish to express our sincere thanks to our patient for consenting to the publication of his case and images; this study would have not been possible without his cooperation. Davagnanam, C.

Fraser, K. Miszkiel, C. Daniel, G. Adult Horner's syndrome: a combined clinical, pharmacological, and imaging algorithm. In some cases, no underlying cause can be found. There's no specific treatment for Horner syndrome, but treatment for the underlying cause may restore normal nerve function. A number of factors, some more serious than others, can cause Horner syndrome.

It is important to get a prompt and accurate diagnosis. Get emergency care if signs or symptoms associated with Horner syndrome appear suddenly, appear after a traumatic injury, or are accompanied by other signs or symptoms, such as:. Horner syndrome is caused by damage to a certain pathway in the sympathetic nervous system. The sympathetic nervous system regulates heart rate, pupil size, perspiration, blood pressure and other functions that enable you to respond quickly to changes in your environment.

The nerve pathway affected in Horner syndrome is divided into three groups of nerve cells neurons. This neuron pathway leads from the hypothalamus at the base of the brain, passes through the brainstem and extends into the upper portion of the spinal cord. Problems in this region that can disrupt nerve function related to Horner syndrome include:.

This neuron path extends from the spinal column, across the upper part of the chest and into the side of the neck. Causes related to nerve damage in this region may include:. This neuron path extends along the side of the neck and leads to the facial skin and muscles of the iris and eyelids. Nerve damage in this region may be associated with the following:. In some cases the cause of Horner syndrome cannot be identified.

This is known as idiopathic Horner syndrome. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.