Interventional neuroradiology (INR) also known as neurointerventional surgery (NIS), endovascular therapy (EVT), endovascular neurosurgery, and interventional neurology is a medical subspecialty of neurosurgery, neuroradiology, intervention radiology and neurology specializing in minimally invasive image-based technologies and procedures used in diagnosis and treatment of diseases of the head, neck, and spine.
History
Diagnostic angiography
Cerebral angiography was developed by Portuguese neurologist Egas Moniz at the University of Lisbon, in order to identify central nervous system diseases such as tumors or arteriovenous malformations. He performed the first brain angiography in Lisbon in 1927 by injecting an iodinated contrast medium into the internal carotid artery and using the X-rays discovered 30 years earlier by Roentgen in order to visualize the cerebral vessels. In pre-CT and pre-MRI, it was the only tool to observe the structures within the skull and was also used to diagnose extravascular pathologies.
Subsequently, European radiologists further developed the angiographic technique by replacing the traumatic direct puncture with catheterization: in 1953, Swedish physician Sven Seldinger introduced the technique of arterial and venous catheterization still in practice, dubbed the Seldinger Technique. In 1964, the Norwegian radiologist Per Amudsen was the first to perform a complete brain angiography with a transfemoral approach, as it is performed today; he then moved to San Francisco to teach the technique to American neuroradiologists. These two stages, at the basis of modern invasive vascular diagnostics, prepared the way for later therapeutic developments.
The first treatments: balloon occlusion
The first to carry out a true endovascular procedure was Charles Dotter, the father of angioplasty and considered by many as the father of all interventional radiology, as well as the first doctor to have performed endovascular treatment. On January 16, 1964, he performed a therapeutic angioplasty of a superficial femoral artery in an 82-year-old woman with an ischemic leg refusing amputation. The artery remained open for the next two and a half years, after which the woman died of pneumonia.
The concept of using balloons to treat cerebrovascular lesions was inspired by a 1959 May Day celebration in Moscow’s Red Square. While watching children use tether lines to manipulate helium balloons, Fedor Serbinenko, a Russian neurosurgeon, began to envision small balloons moving through tortuous arteries. In the 1970s Fedor Serbinenko developed a technique for closing intracranial aneurysms with balloons that were released into the internal carotid artery by occluding the lumen. The first treatment was performed in 1970 in Moscow, with the occlusion of an internal carotid to treat a carotid-cavernous fistula. He can be considered, therefore, the first interventional neuroradiologist. This technique was subsequently refined by neuroradiologists all over the world and mainly in France, where interventional neuroradiology developed and flourished.
Parallel to the development of catheters, in the radiology and neuroradiology units, image technology dramatically improved: Charles Mistretta in 1979 invented digital subtraction angiography (DSA), the technique currently in use. It consists of performing skull radiography under basic conditions which are then "subtracted" to the image after contrast media injection, to provide an image where only brain vessels are displayed, with great improvement in the diagnostic potential.