time of examination by lack of the expansile blood stream that characterizes them in life. Also confusing the picture of the dead lesion are the alterations produced in the component vessels by blood under arterial pressure, which dilates veins and “arterializes” them to withstand the added stress. Vascular resistance being lowered by the shunt, arteries dilate to carry more blood under less than usual pressure, and lose some of their usual characteristics.”
However, the introduction of cerebral angiography (Moniz 1927) together with the continuing improvements in the quality of angiograms and the remarkable developments in vascular catheterization techniques (Seldinger 1953, Djindjian 1962) has opened up new dimensions in the study of the morphological and hemodynamic aspects of AVMs.
This short historical review may help to understand how we have arrived at the present day interpretations of AVM pathology and development and how modes of treatment have evolved.
Pre-17th Century
Descriptions of vascular malformations of the skin and other visible organs such as eye, lips and ear with occasional comments about their often ugly appearance and the difficulty or impossibility of treatment may be seen in some of the earliest recorded historical manuscripts.
The Papyrus Ebers (ca. 1500 BC) contained descriptions of hemorrhoids, skin tumors, hydroceles, varicose veins and aneurysms. Kharadly (1956) showed that hernias and aneurysms were operated upon even in those times but not AVMs. The warning, “You must keep your hands off – Noli me tangere” is stated in the relevant chapter.
Virchow cited prominent physicians like Hippokrates, Galen, Celsus, Aetius, Avicenna, and Vidus Vidius, who were dealing with the diagnosis and treatment of different types of external vascular malformations. Von Bramann (1886) showed that Galen and Delia Groce knew of varicose pulsating swellings and took them to be simple arterial aneurysms. Osier (1915) noted that references to vascular malformations are to be found in the works of Antyllus (2nd Century) and Abulcasis (10th Century).
17th–19th Century
The great breakthroughs in the understanding of the systemic circulation and of the cerebral circulation were made by Harvey (1628) and Willis (1664) respectively.
William Hunter (1718–1783)
(By kind permission of the President and Council of the Royal College of Surgeons of England)
John Hunter (1728–1793)
The work of Harvey and Willis was subsequently complemented by the discovery of the capillary system by Malpighi (1661) and this paved the way for modern theories regarding the evolution and pathology of AVMs.
In the following century (1757) William Hunter was able to identify the clinical characteristics and some hemodynamic aspects of extracranial AVMs. In “Observations on arteriovenous malformation, London Medical Observations and Enquiries, 1762” he wrote: “Vascular malformations of the extremities are caused by an abnormal communication between arteries and veins.” Enthusiastic phlebotomists of that period prepared two perfect examples of arteriovenous aneurysm for W. Hunter, which he was quick to recognize (cit. Dandy 1928); at the point of communication between the artery and the vein, he recognized a loud hissing bruit and a strong tremulous thrill: large tortuous sacs were seen to pulsate; the brachial artery was greatly enlarged and serpentine cephalad to the arteriovenous fistula, but distal to it, the artery became smaller than on the other side. He was able to reduce the size of the vein, stop their pulsation and eliminate both the bruit and the thrill by pressing on a localized spot, which he recognized to be the opening between the artery and vein. It was William Hunter who first suggested the term “anastomosis” to denote the union of the two vessels, whereas the term “collateral” was introduced by his younger brother John Hunter who also ligated the femoral artery in a case with popliteal aneurysm and proved the efficiency of the collateral arterial system.
The broad scientific approach concerning the nature of these impressive aberrations began with pathologists and surgeons 200 years ago who described them as “erectile tumors” and swellings of the skin and organs. The advent of medical journals enabled the scientists to publish their observations.
After 1850 the number of publications concerning these erectile tumors increased rapidly. Between the time of William Hunter (1762) and Sonntag (1919), 65 such publications are to be found: Plenck (1776), Bell (1796), Cruveilhier (1816), Meckel (1818), Dupuytren (1834), Vidal (1846), Rokitansky (1846), Virchow (1851), Gerdy (1852), Schuh (1853, 1866), Busch (1854), Luschka (1854), Esmarch (1854), Lebert (1857), Bennet (1854), and Alibert (1871). More detailed information regarding these papers may be found in the works of Heine (1869), Weber (1869), Körte (1880) and Heineke (1882). Pathological classification based upon varied anatomical descriptions was already becoming clumsy and confusing. By 1894 Wagner had collected from the current literature 24 different nomenclatures. In parallel with changing pathological concepts, the surgery of extracranial AVMs was undergoing a gradual evolution.
Treatment of Extracranial AVM in Earlier and Present Time
The endeavours of general surgeons in dealing with the dangerous and disfiguring extracranial vascular malformations (scalp, external ear, eyelids, orbits, cheeks, lips, tongue, palate and neck) are most informative for the interested neurosurgeon (Beck, Berger, Billroth, Brodie, von Bruns, Bryant, Busch, Caradec, Clairmont, Dalrymple, Dupuytren, Emanuel, Enderlen, German, Goldmann, Heineke, Krause, Lefort, Lieblein, Nélaton, Pilz, Roth, Russell, Schwalbe, Schwartz). Their methods of treatment have, in the past, included:
1) Injection of the lesion with: ferrous chloride, glycerin, tannin, chlorzin, carbonic acid, alcohol,
2) Electrocauterization,
3) Ligation,
4) Extirpation.
The variety of modern therapy of external vascular malformations (Williams 1983) shows that therapeutic difficulties still remain in the treatment of these easily approachable lesions:
1) Corticotherapy (new born children),
2) Radiotherapy,
3) Electrocoagulation,
4) Cryotherapy,
5) Surgery,
6) Use of laser beam,
7) Embolization.
As in neurosurgery, the advice of most plastic surgeons is that simple ligation of feeding vessels is inadequate and inadvisable.
Intracranial Angiomas
The Contributions of Virchow and his Contemporaries
After exhaustive research work on cavernomas of the liver, Rokitansky (1842–46) came to the conclusion that these were either benign or malignant tumors independent of the surrounding vascular system. Volume 6 of Virchow’s Archive (1854) contains 3 remarkable papers: Esmarch (pp. 34–57): “Über cavernöse Blutgeschwülste”, Luschka (pp. 458–470): “Cavernöse Blutgeschwülste des Gehirns” and Virchow (pp. 526–554): Über cavernöse (erectile) Geschwülste und Teleangiektasien.” Esmarch und Luschka fully supported the neoplasia hypothesis of Rokitansky.
Luschka provided one of the earliest descriptions of an intracranial arteriovenous anomaly in a patient
