[Vascular cause of hemianopsia].

Hemianopsia of vascular origin can be caused by diseases in the carotid circulation (optic tract, proximal third of the optic radiation), as well as in the vertebrobasilar arterial system (middle and distal thirds of the optic tract, striate area/calcarina). Hemianopsia of ischemic origin must be differentiated from hemianopia in the presence of an enlarging aneurysm, a space-occupying intracranial lesion (hemorrhage, neoplasia), and inflammatory disease, occasionally in metabolic disorders. To detect the exact cause of a hemianopia in a given patient, recording of the patient's precise history and clinical-neurological, clinical-ophthalmological, and clinical-internal examinations are mandatory, as well as additional diagnostic procedures. Of these, the most important are neurovascular ultrasound examinations (extracranial, transcranial and B-mode/duplex Doppler examination), CT and MRI scans, and cardiological examination with echocardiography. The choice of these additional and costly examinations and their sequence in the diagnostic work-up in a given patient has to be adapted to the patient.