Brain Arteriovenous
Malformation (AVM)

Andreas Vesalius, a Renaissance physician, was twenty-eight when he published De Humani Corporis Fabrica — seven books of human anatomy built on his own dissections. Book III, Chapter 14 contains the first detailed rendering of the cerebral vasculature: the arteries and veins of the brain, laid out as a branching tree.

Vesalius had no word for arteriovenous malformation. The concept didn’t exist yet. But the territory was now on the map, and everything that followed depended on that.

Three centuries later, a German anatomist Hubert von Luschka opened the skull of a man who had taken his own life and found something tangled in the brain tissue — a mass of abnormal vessels that didn’t belong to any normal anatomy. He wrote it up for Rudolf Virchow’s journal in Berlin: Cavernöse Blutgeschwulst des Gehirnes“Cavernous blood-tumour of the brain”The title of Luschka’s 1854 paper in Virchow’s Archiv — the first careful description of what we now call a cerebral vascular malformation. He used the German word Blutgeschwulst (literally “blood-tumour”) because the lesion looked like a tumour of vessels; the modern distinction between malformation and tumour didn’t yet exist.. A cavernous blood tumor of the brain.

Luschka’s brain AVM description was careful and clinical. He distinguished two types of vascular malformation and placed them in the pathological record. The thing had a name now, and a place in the literature. What it didn’t have was a way to be seen in a living person, or any prospect of being treated.

In 1867, Jules-Émile Péan, a Paris surgeon with a reputation for bold operations, performed the first recorded attempt to treat a cerebral vascular malformation surgically — ligating the feeding vessels in hopes of starving the lesion.

It was a beginning, though the tools and the understanding were crude. The operation existed as a concept, but the mortality was severe and the anatomy was largely guesswork. Surgeons were working blind.

Egas Moniz changed that. Working in Lisbon, he developed cerebral angiography — injecting contrast into the carotid artery and taking X-rays as it flowed through the brain. For the first time, a living patient’s cerebral vasculature could be photographed. The tangled vessels that Luschka had found at autopsy seventy years earlier were now visible on film, in real time, before any incision was made.

Moniz published his technique in 1927. It earned him a Nobel Prize (for a different, far more controversial procedure), but angiography was the lasting contribution. Every AVM diagnosis for the next six decades would depend on it.

Harvey Cushing at Harvard and Walter Dandy at Johns Hopkins were the two dominant figures in American neurosurgery, and they agreed on almost nothing. In 1928, both attempted surgical removal of brain AVMs. Both reported catastrophic results.

Cushing, meticulous and cautious by nature, described the hemorrhages as uncontrollable. Dandy, who was more aggressive, fared no better. The lesions could now be seen on angiography, but touching them remained close to suicidal. These early attempts confirmed what every surgeon suspected: AVMs were visible, diagnosable, and lethal to operate on.

Four years later, Herbert Olivecron at Serafimerlasarettet hospital in Stockholm, began a systematic surgical program for brain AVM removal that would span decades. He operated carefully, developed his own techniques, and kept records. His results improved slowly. By the time his trainees carried the work forward, surgical treatment of AVMs had moved from desperation to discipline — still dangerous, but no longer unthinkable.

Stockholm’s Serafimerlasarett became the place where neurosurgeons came to learn that patience and technique could do what courage alone could not.

Three decades later, a Turkish neurosurgeon named Mahmut Gazi Yaşargil arrived at the University Hospital in Zurich with an idea borrowed from vascular microsurgery: if you operate under a microscope, with instruments scaled to the vessels you’re working on, you can do things that are impossible with the naked eye.

After Yaşargil, small and medium AVMs, which prior seemed like death sentences, became routinely operable. In 1999, the journal Neurosurgery named Mahmut Gazi Yaşargil Neurosurgeon of the Century. He died on June 10, 2025, shortly before his hundredth birthday.

By the mid-1980s, thousands of AVMs had been operated on worldwide, but there was no shared system for comparing them. A small AVM on the brain’s surface was a different problem from a large one buried in the motor cortex, and surgeons had no common language for that difference.

In 1986, Robert Spetzler and Neil Martin at the Barrow Neurological Institute in Phoenix proposed something simple: three variables — the size of the malformation, whether it sat near critical brain tissue, and whether its veins drained deep or toward the surface. Add the scores and you get a grade from I to V. Grade VI meant inoperable.

The paper was eight pages long, but it became the most cited article in the AVM literature, and four decades later, every neurosurgeon in the world still uses it.