Palsy of the abdomen

Classification according to ICD-10
H49.2	Paralysis of the abducens nerve [VI. Cranial nerve]
ICD-10 online (WHO version 2019)

As a sixth nerve palsy damage to the will Abducens , the VI. Cranial nerve . This leads to a paralysis of the lateral rectus muscle supplied by the abducens nerve , a straight eye muscle that turns the eyeball outwards towards the temple .

Symptoms

A paralysis of this muscle leads to its partial or complete loss of function with a resulting hyperfunction of its equilateral (ipsilateral) antagonist , the musculus rectus medialis . The result is an inward squint of the affected eye. The close squint angle is usually smaller than the remote squint angle.

A key symptom of abducent nerve palsy is the restriction of the monocular field of vision in the direction of muscle pull and the associated double images , the distance between which increases when looking towards the affected eye. In order to maintain simple two-eyed vision , a conspicuous forced head posture is often adopted, usually in the form of a head rotation to the affected side. A double image perception, which only occurs when looking into the distance and not when looking close, can also be an indication of bilateral palsy of the abdomen. Furthermore, there is a large secondary angle , a squint, which is significantly larger when fixed with the affected eye than when fixed with the healthy eye (primary angle). In addition, the size of the squint angle varies depending on the viewing direction ( incomitance ).

etiology

Damage to the abducent nerve usually occurs within the cavernous sinus , which is prone to inflammation and thrombosis and through which the nerve runs. Due to its course along the base of the skull, the nerve is often affected by fractures of the base of the skull or meningitis .

Abdominal paralysis also occurs with some syndromes :

therapy

As with all neurological disorders, once the cause has been clarified, treatment is primarily in the hands of a neurologist. If the situation has not improved significantly after 6–9 months, a squint operation may be indicated. As a rule, the aim of this is to shift the field of binocular simple vision into the primary position, i.e. without adopting a forced head posture, and, if necessary, to enlarge it. There are various options for this, depending on the available findings. If the eye can move up to the midline, a so-called combined operation with strengthening of the affected lateral rectus muscle and simultaneous weakening of the medial rectus muscle can be considered.

A further procedure can be carried out according to the principle of a so-called counter- paresis by weakening the contralateral rectus medialis muscle (e.g. by repositioning or by a Cüppers thread surgery ). The principle of action here is to transform the ocular muscle paresis into an artificial (artificial) paralysis of the eye with a reduction in the secondary angle and to achieve a corresponding increase in innervation of the paretic muscle when the non-paretic eye is guided, which is equivalent to a change in the primary angle.

Muscle transpositions (displacements of the muscle insertion) should only be considered when the affected eye can hardly moved even from the nasal canthus and after elektromyographischem finding a complete paralysis ( paralysis exists).

In the case of very minor paresis, adjusting prism lenses can help improve the situation.

Differential diagnosis

In the differential diagnosis, the abducens palsy is to be contrasted with the Stilling-Türk-Duane syndrome , which is also based on a lesion of the abducens nerve, but which also has an additional mislinervation of the lateral rectus muscle by neurons of the oculomotor nerve with its own symptoms.

swell

literature

Herbert Kaufmann (Ed.): Strabismus. With the collaboration of Wilfried de Decker et al. Enke, Stuttgart 1986, ISBN 3-432-95391-7 .
Rudolf Sachsenweger (Ed.): Neuroophthalmology. 3rd, revised edition. Thieme, Stuttgart et al. 1982, ISBN 3-13-531003-5 .

Individual evidence

↑ Bernfried Leiber (founder): The clinical syndromes. Syndromes, sequences and symptom complexes . Ed .: G. Burg, J. Kunze, D. Pongratz, PG Scheurlen, A. Schinzel, J. Spranger. 7., completely reworked. Edition. tape 2 : symptoms . Urban & Schwarzenberg, Munich et al. 1990, ISBN 3-541-01727-9 .
↑ Commission "Guidelines of the German Society for Neurology" (Ed.): Guidelines for Diagnostics and Therapy in Neurology. 3rd, revised edition. Georg Thieme, Stuttgart et al. 2005, ISBN 3-13-132413-9 , keyword: Peripheral eye muscle and nerve paresis; AWMF guidelines register: No. 030/033.

[1] Bernfried Leiber (founder): The clinical syndromes. Syndromes, sequences and symptom complexes . Ed .: G. Burg, J. Kunze, D. Pongratz, PG Scheurlen, A. Schinzel, J. Spranger. 7., completely reworked. Edition. tape 2 : symptoms . Urban & Schwarzenberg, Munich et al. 1990, ISBN 3-541-01727-9 .

[2] Commission "Guidelines of the German Society for Neurology" (Ed.): Guidelines for Diagnostics and Therapy in Neurology. 3rd, revised edition. Georg Thieme, Stuttgart et al. 2005, ISBN 3-13-132413-9 , keyword: Peripheral eye muscle and nerve paresis; AWMF guidelines register: No. 030/033.