[Dissecting aneurysm with damage to median nerve].

A case of iatrogenic dissecting aneurysm in the cubital region causing secondary damage to the median nerve is reported. This aneurysm was caused by an attempted venipuncture, in what can be considered a minor procedure. Such a severe complication is very remarkable, for it has not been observed so far even in much more potentially hazardous procedures as, for instance, in the numerous arterial punctures in the cubital region being daily performed for retrograde angiography of the cerebral vessels. In this case the reduced blood coagulation is discussed as a causing factor of this unusual complication.