Horner's syndrome

Horner's syndrome (also Horner 's triad ) is the specific form of nerve damage called, which is caused by the failure of Sympathikuskopfteils, a portion of the involuntary nervous system. It has an almost one- occurring three-piece symptom complex ( Triassic) on consisting of a pupillary constriction ( miosis ), drooping of the eyelid ( ptosis ) and a small sunken into the eye socket eyeball ( enophthalmos ). The disease was described in 1869 by the Swiss ophthalmologist Johann Friedrich Horner for the first time and therefore named after him.

Symptoms

Miosis

The pupillary constriction ( miosis ) occurs due to the failure of the sympathetically innervated dilator muscle of the pupil ( Pupillenerweiterer ) in the iris. It occurs by a Dilatationsdefizit in the dark, that is, the pupil dilates not like usually in the dark. Affected therefore sometimes report of visual impairment in a dark environment.

Retraction of the eyeball

The lower back into the eye socket eyeball ( enophthalmos ) is caused by the failure of the sympathetically innervated muscle orbital. It involves smooth muscle in the periorbita, the outer connective tissue of the eye. The tone of this muscle normally ensures that the eye is slightly pushed outward. This form of enophthalmos is contrary to the cramps in the outer striated extraocular muscles (musculus retractor bulbi, recti muscles of the eyeball ), barely visible. In the literature, different opinions, see whether the enophthalmos only faking when Horner syndrome due to the ptosis ( Pseudoenophthalmus ), or actually exists by the impairment of the orbital muscle.

In animals, a partial prolapse of the nictitating membrane (also referred to as the "third eyelid " ) occur.

Drooping eyelid

The drooping of the eyelid ( ptosis ) is due to the failure of which likewise consists of smooth muscle and sympathetically innervated musculus tarsalis (also shear Müller muscle) caused. This muscle pulls on the healthy eye, the eyelid in vertical direction.

The actual lift muscle of the upper eyelid, the levator palpebrae superioris, is much stronger and is composed of striated muscle. He is generally somatomotorisch innervated by the oculomotor nerve and is therefore not affected when Horner syndrome. The ptosis is less pronounced in Horner syndrome than a failure of the oculomotor nerve. Moreover, while at Levatorlähmungen present a inkomitierende ptosis, the degree of ptosis in the Horner syndrome in all viewing directions is approximately equal.

Other signs

In addition to these classical three main symptoms ( Triassic) on the eye occur more symptoms such as vasodilation ( vasodilation ) and diminished sweating in the affected part of the face ( anhidrosis ) at a Sympathikusausfall. Pigment spots in the eye, different pupil size and different coloration of the iris are more clues.

Pathophysiology

Through failures along the anatomical course of the sympathetic innervation to the head region, the individual symptoms of Horner's syndrome can be explained and subsequently for the peripheral portion, not the central nervous proportion shown:

• First neuron ( nerve cell first ): The cell body ( soma ) of the sympathetic nervous system are localized (chest part of the spinal cord ) in the upper thoracic spinal cord. From there, pull axons ( projections of neurons ) in the direction of the corresponding ganglia.
• Stellate ganglion: The axons of the nerve cells of the sympathetic nervous system extend within the sympathetic trunk cephalad. Relevant for the Horner 's triad axons traverse the stellate ganglion without being switched there. A Horner's syndrome, for example, be an indication of a successfully implemented stellate.
• Cervical part of the sympathetic nervous system: it is in most mammals as truncus vagosympathicus ago. This strain pulling on the neck together with the common carotid artery dorsal (on the back of the facing side ) of edible and trachea towards the head.
• Second Neuron: The changeover is called in humans in the superior cervical ganglion, in animals as cranial cervical ganglion. This ganglion is located ventrally ( ventral ) of the upper cervical vertebrae. In animals it is caudal ( tail down) to find near the skull base.
• " Internal carotid plexus ": On the way the sympathetic fibers may be damaged during the passage (without switching) through the internal carotid plexus through a dissection of the internal carotid artery.
• Ciliary ganglion: The sympathetic nerve fibers pass this parasympathetic ganglion located behind the eye without further change and thus reach the eye.

Based on the superior cervical ganglion of a preganglionic a postganglionic damage to the sympathetic innervation of the head region is distinguished. The latter is generally regarded as less dangerous.

Causative diseases

A Horner's symptom complex may be necessary in the following diseases and conditions:

• Dissection of the common carotid artery, the internal carotid artery or vertebral artery
• Pancoast tumor
• Cervical syringomyelia
• Wallenberg syndrome
• Stellate
• Injuries in the thoracic and cervical spine
• Lower Armplexuslähmung (type Klumpke )
• Neuroblastoma
• Struma
• Thyroid
• Cluster Headache
• Esophageal carcinoma
• As a side effect of interscalene block
• As a complication of a thoracic aortic aneurysm
• As a rare complication of cervical herpes zoster infection.
• As a rare complication of puncture of the internal jugular vein.

Diagnosis

Therapy

No treatment is known. In some cases it is reported that regress depending on the cause of the external symptoms even after a few months, partly again.