Antonio Egas Moniz, (1874-1955), introduced and developed (1927-1937) cerebral angiography, by injecting opaque contrasts to x-rays into the carotid artery.
Moniz experimented with different contrast media in order to visualise the brain vessels. He selected lithium bromide, strontium bromide and sodium iodide and he performed experiments, in cadavers, animals and humans.
His first eight attempts were failures with one patient dying after the injection of contrast. Success was achieved on the ninth patient when the branches of the intracranial carotid appeared clearly visible on film. This allowed Moniz to describe arterial displacement and abnormal vascularisation in brain neoplasms and also make the diagnosis of cerebral aneurysms. Moniz found that sodium iodide was the less toxic. Twenty years later in 1957 an organic iodide contrast (Renographin) which had three atoms of iodine came into use and found to be less toxic. The organic iodine contrast were replaced in the 70s with nonionic contrasts which had fewer adverse effects due to their decreased osmolality and are in use today in the performance of angiography, interventional procedures and also in intravenous injection in computed tomography.
Although Moniz was nominated three times for the Nobel Prize for the discovery of cerebral angiography, he was never awarded for the discovery of this diagnostic tool. Moniz won the Nobel Price for Medicine in 1949 (together with Walter Rudolf Hess) for the operation of prefrontal leukotomy which was used in the treatment of psychoses, a procedure less important than brain angiography and not in use today .
