Bonnet–Dechaume–Blanc syndrome

The Bonnet- Dechaume -Blanc syndrome, also Wyburn - Mason syndrome or congenital retinozephalofaziales vascular malformations syndrome (CRC syndrome ) is a rare syndrome characterized by the occurrence of usually one-sided arteriovenous malformations ( AVM ) of the blood vessels of the retinal and intracranial blood vessels ( cerebral arteriovenous malformations ) and characterized by changes of the face is.

Some authors include the syndrome to the neurocutaneous diseases.

Term

A review in 2008 evaluated the data of all published in the medical literature case reports. The authors divided the following characteristics of the malformation:

• Full / typical congenital vascular malformations retinozephalofaziales syndrome (CRC syndrome ) or classical Bonnet- Dechaume -Blanc syndrome - Arteriovenous malformations of the retina and the brain vessels and involvement of the skin
• Incomplete congenital vascular malformations retinozephalofaziales Syndrome - Arteriovenous malformations of the retina and the brain vessels
• Isolated retinal arteriovenous malformations - exclusively arteriovenous malformations of the retina
• Arteriovenous malformations of the retina and clinical neurological findings, but no neuroradiological imaging

Epidemiology

All forms of the syndrome are very rare. Until 2009 132 cases have been reported, 27 of which a complete CRC syndrome, 30 an incomplete CRC syndrome and 63 isolated retinal arteriovenous malformations had. A further 12 cases were affected with malformation of the ocular vessels and presumed cerebral arteriovenous malformations, but without neuroradiological evidence. In the frequency there are no gender differences. The diagnosis is usually in the second or third decade of life.

Pathology

In arteriovenous malformations are shunts between the arterial and the venous vasculature. The often knäulförmig scale vessels thus represent a connection between the high - and the low-pressure system dar. The pressure gradient results in increased vascular blood flow and dilation of the vessels. The vascular bed is a continuous conversion ( " remodeling" ) subject. Damage to the vessel wall lead to complications such as stenosis and Gefäßrupturen.

The arteriovenous malformations, both the retina and the brain vessels, is based on a developmental disorder of unknown cause at the 7th week of pregnancy.

Clinical manifestations

According to the form of the CRC syndrome resulting changes of the face, eyes and / or intra-cranial vessels. In addition, bleeding may occur from the mouth and nose bleeds. In affected individuals occurred in tooth extractions sometimes life-threatening bleeding.

The changes usually occur on one side, rarely on both sides.

Face changes

In patients with complete CRC syndrome occur next to arteriovenous malformations of the retina and the brain vessels various unilateral facial changes, including some prominent vessels of the conjunctiva ( conjunctiva ) of the cheeks and forehead, as well as changes in the Lidgefäße. Occasionally, Lidveränderungen also in the area on the lips, ear and nose.

Ocular changes

Changes in the eyes occur when incomplete CRC syndrome and in isolated retinal arteriovenous malformations. Almost half of the patients described is blind on the affected side of the body. Other complications of retinal arteriovenous malformations include secondary glaucoma, and more rarely the optic atrophy. Retinal hemorrhage and vitreous hemorrhage have been described. By cerebral AVM may occur as eye motility of exotropia ( divergent strabismus ) and nystagmus. About two-thirds of those affected in the eye socket (orbit ) arteriovenous malformations are detected, which often result in cerebral vascular malformations in addition to a one-sided proptosis and partly related to intracranial AVM. The involvement of vessels of the eye socket may also lead to a deterioration of the optic nerve ( optic nerve ).

Intracranial vascular changes

Arteriovenous malformations of cerebral vessels occur during complete and incomplete CRC syndrome. They occur particularly in the supply area of the middle cerebral artery (ACM ) in the supply area of the anterior cerebral artery and posterior they occur less frequently. In approximately one third of cases described, found the vascular changes in the cerebral part of the visual pathway.

These vascular lesions may remain asymptomatic throughout life. Your common complications are various forms of cerebral hemorrhage, particularly Intracerebral bleeding (ICB ) but also subarachnoid hemorrhage (SAH ). Occasionally, vascular malformations can also be manifested in a symptomatic epilepsy or increased intracranial pressure.

Several cases of Bonnet- Dechaume -Blanc syndrome have been described in which a facial nerve paralysis ( Bell's palsy ) occurred.

Methods of investigation

If you suspect the presence of a CRC syndrome, a neurological examination process and a ophthalmologic diagnostics (ophthalmoscopy, perimetry) takes place. For radiological arteriovenous malformations representation of the magnetic resonance imaging ( MRI ) may occur, computed tomography ( CT) and digital subtraction angiography (DSA ) for the application.

Treatment

Arteriovenous malformations can - after assessment of the risk of bleeding - are treated by microsurgical resection or embolization. If the secondary changes in the retina due to a CRC syndrome may be indicated laser photocoagulation.

History

Numerous case reports, including one written by Hugo Spatz work of 1874 and a report Arthur Cross ' from 1903, described aspects of the syndrome. Detailed case reports, including those by Ernst pitcher and Bernard Samuels (1932 ), all components of the syndrome - arteriovenous malformations of the retina, the brain vessels and the facial skin - described are from the 1930s. The eponymous for the Bonnet- Dechaume -Blanc syndrome ' case report was published in 1937 by Paul Bonnet, Jean Dechaume and Emile Blanc, the report Roger Wyburn - Mason in 1943 coined the term Wyburn - Mason syndrome.