top of page

El origen de las fístulas arteriovenosas durales espinales

OBJECTIVE : Arteriovenous malformations (AVMs) of the spinal cord are rare lesions that have become more frequently diagnosed in the last 20 years due to the technical advances in neuroradiology and the better understanding of several clinical and pathophysiological aspects of this group of vascular lesions.

These lesions are classified in four main types. Type I (spinal dural arteriovenous fistulas) represent 80 to 90% of all spinal AVMs and it is widely accepted that are acquired entities. The purpose of this article is to review the literature about the etiology of the spinal dural arteriovenous fistulas (AVFs) and present a case that supports the accepted hypothesis of the acquired origin of these lesions.

METHODS : A thorough review of the literature about the origin of the spinal AVMs with special consideration to type I lesions was undertaken and a rare case of a patient with a spinal dural AVF who was previously treated for a Pott’s disease is reported.

RESULTS : There are indirect evidences supporting the hypothesis of the acquired origin of type I spinal AVMs. These include: the age of onset later in life, the duration of signs and symptoms less than 2 to 3 years, the absence of the disease in childhood and the similarities with cranial dural arteriovenous fistulas which are recognized as acquired entities.

CONCLUSION : The review of the literature strongly supports the hypothesis of the acquired origin of spinal dural AVFs. The case reported in this article may be the confirmation of this hypothesis.

Key words : Dural fistula, Myelopathy, Spinal arteriovenous malformation,

Spinal dural fistula, Spine, Vascular malformation.

Spinal cord arteriovenous malformations (AVMs) are rare lesions that have become more frequently diagnosed due to the increasing knowledge of its natural history, its pathophysiology, the evolution of the surgical techniques and the technological advances in neuroradiology (1, 2, 5, 9, 10, 16, 17, 19, 20, 26).

These lesions are classified in four main types according with Heros and Anson and Spetzler (4, 18). Type I or spinal dural arteriovenous fistula (AVF) is a shunt located at the dural sleeve of a spinal root feed by a radiculomeningeal artery with an intradural part composed by the dilated but otherwise anatomically normal venous perimedullary plexus, located on the dorsal pial surface of the cord. This type comprises about 80 to 90% of the spinal AVMs.

Type II or glomus type is an AVM with a true nidus located totally in the substance of the spinal cord or may have a part intramedullary and other part extramedullary.

Type III or juvenile type, the most complex, has a large nidus extending from the inside cord to the epidural space, vertebral body and paravertebral tissues over several segments with multiple feeders and drainages.

Type IV or direct spinal arteriovenous fistula is a direct fistula between the anterior spinal artery and a vein, usually perimedullary and anterior to the cord, with large dilation of the venous system. Type IV-a is a perimedullary fistula fed by a single arterial ramus. Type IV-b is a mid-size perimedullary fistula with

multiple arterial feeders. Type IV-c is a large perimedullary fistula fed by

multiple dilated arterial feeders.

It is widely accepted the congenital origin of types II, III and IV spinal AVMs but the mechanism by which spinal dural AVFs arise is less clear. Evidence supports an acquired etiology (7, 15, 16, 24, 25, 26).

The age of onset later in life (more than 80% older than 40 years), and the absence of the disease in childhood argue for the development with time. In 172 cases reviewed from the literature and their own series by Berenstein and Lasjaunias the youngest patient was 26 years old and Rosemblum’s youngest patient was 25 years old. There are no reported cases of spinal dural AVFs present at birth or childhood (7, 32).

Eighty to 90% of the patients harboring a spinal dural AVF are men, in contrast, the other types of spinal AVMs have no significant male preponderance. This suggests that trauma or heavy physical activity might be factors involved in the development of spinal dural fistulas (24, 25).

The duration of clinical manifestations of less than 2 or 3 years after the onset in a previously asymptomatic patient is another reason to suspect the acquired origin of the spinal dural AVFs (25).

The cranial dural AVFs, which are recognized as acquired entities related to venous sinus thrombosis or trauma, have similarities to the spinal dural AVFs. Despite this similarities shared by both groups, no history of trauma can be related to the development of a fistula in the spinal group (25). In 1988 Yoshino reported a case of a 27 year old man in which a diagnostic of a spinal dural AVF was done 7 years after a normal myelogram for a disc disease (37).

The preferential location for the thoracolumbar region rather than being uniformly distributed along the entire spine (like the tendency with the congenital AVMs of the spinal cord) is another reason to support the hypothesis of the development of these lesions after birth (25).

The author presents a case with a direct relation between a previous disease, spinal tuberculosis, and the later development of myelopathy secondary to venous hypertension from a spinal dural AVF at the same level.

CASE REPORT

A 38 year-old man was referred from another institution complaining about numbness in both legs, claudication and increasing difficulty in walking on foot with frequent falls, lumbar pain, and bowel, bladder and sexual dysfunction. The symptoms had begun one month before and had been progressing in the last week previous to the admission. The neurological exam showed a moderate paraparesis predominantly to the right, unable to walk more than 10 meters, bilateral increased muscle tone, discrete hyperreflexia both in patellar and Achilles reflex, bilateral Babinski sign and a T12 level of hypestesia.

Twenty-four months before, the patient had been treated at another institution for a L2-L3 vertebral osteomyelitis due to M. tuberculosis diagnosed through needle biopsy. The patient only complained of lumbar pain without any other neurological symptom due to this disease. He was treated with standard antituberculosis therapy of three drugs (streptomycin, isoniazid, ethambutol) during 8 months with resolution of the symptoms.

The T2-weighted magnetic resonance imaging (MRI) scan showed the secuelae of the previous process at L2-L3 with mild kyphosis, but most important, in the spinal canal there were multiple serpentine flow voids between the roots of the cauda equina and around the cord from L3 up to T1 (Figs.1a and b). The selective digital angiography showed a spinal dural AVF fed by the left L2 radicular artery with arterialization of the normal venous system of the cord (Figs. 2a, b and c).

The patient increased the deficit after the angiography and became paraplegic four days after the procedure.

Two weeks later, the lesion was approached through a standard laminectomy from L1 to L3, with a foraminotomy to expose the left L2 root. Under the operating microscope the dura was opened in the midline and over the root. The dura of the root was inspected but no communication between an arterial feeder and the intradural arterialized vein was found. Then the arachnoid was opened and the dilated vessel was followed intradurally to the foramen (Fig. 3a). A temporary clip was placed near the entrance of the vessel (Fig. 3b), a little change in the color into bluish and decreasing the turgor of the intradural (venous) part of the fistula was noted. Then the clip was removed

and the vessel was coagulated and cut (Figs. 3c and d). The dura was closed in watertight fashion.

Due to the instability produced by the previous disease and the laminectomy with resection of an articular process, a fusion procedure was done with a titanium Hartshill rectangle (Surgicraft, De Puy, Buenos Aires), sublaminar wires and autologous bone graft from T11 down to L5.

In the first postoperative day the patient began to have slight movements in the distal parts of both legs, although not against gravity and referred some improvement in the sensibility. At the end of the first postoperative week he

began to move the proximal muscles of the legs.

In the sixth postoperative day a thoraco-lumbar-sacral orthosis was put on and an intensive rehabilitation program was initiated.

The only complication was a superficial wound infection due to E. coli, treated with local measures and ciprofloxacin with good result.

The postoperative imaging study shows disappearance of the dilated vascular images and stabilization of the spine, with the secuelae of the original infectious process (Fig. 4).

Forty-eight months after the surgery the patient is free of lumbar pain. He improved to a moderate paraparesis, can walk aided with cans more than 50 meters and most muscles have 3-4 / 5 of muscular strength. Still has a bilateral hypestesic level at L1, needs intermittent catheterism of the bladder but regained the control of the bowel and has a satisfactory sexual function (Fig. 5).

DISCUSSION

Pathologists in 1885 Hebold and in 1888 Gaupp who named as “hemorroids of the pia mater spinalis” did the first descriptions of spinal AVMs. But it was Brasch, in 1900, who made the first detailed description of the features of spinal dural AVM (6, 8, 13, 14).

The first surgeon who found a vascular lesion in the operating room and the patient survived the surgery, although did not improved, was Krause in 1912 (25).

Elsberg performed the first successful surgery of a spinal dural AVF in 1914. The patient had a severe paraparesis with a T9 sensory level and an abnormal vessel piercing the dura near the ninth thoracic level. Elsberg only excised a segment of the intradural vessel without disturb the rest of the dilated veins, a very similar surgical tactic in use today with microsurgical techniques. The patient recovered to a normal neurological state (11).

In 1915 Cobb reported a case of an 8 year old boy who suffered severe back pain and developed paraplegia. At surgery many dilated vessels were found overlying the spinal cord, only the laminectomy and dural opening was done in this case (25).

Over the next years many reports of cases by Spiller and Frazier, Frazier and Russell, Puusepp, and Sargent, with little variants in the clinical manifestations were presented with distinct surgical approaches, laminectomy

alone, laminectomy and ligature of abnormal vessels and posterior roots or laminectomy and postoperative radiation. The surgical results reported were generally poor (25, 31, 33).

In 1926 Foix and Alajuoanine described a clinical picture called “subacute necrotizing myelopathy” composed of an ascending spastic paralysis that later changed in flaccid and anesthetic with high protein levels and slight lymphocytosis in the cerebrospinal fluid. At autopsy they found large areas of necrosis in the thoracic, lumbar and sacral cord coexisting with enlarged medullary vessels (12).

Michon in 1927 described another clinical presentation, a spinal subarachnoid hemorrhage, as “a stab in the back” (25).

Perthes in 1927 was the first in diagnose preoperatively a spinal angioma by myelography. The first significant progress in neuroradiology of the vascular diseases of the cord. (30).

But it was not until 1943 when Wyburn-Mason published his monograph that most of the clinical, pathological and surgical published material and cases added of his personal series was put together and evaluated, what let him to initially make the difference between venous and arteriovenous malformations. He named the spinal dural AVFs as “Angioma Racemosum Venosum” (35).

Another important progress was the introduction of the selective spinal angiography in the early sixties, first by Djindjian and later by Doppman and

Di Chiro. This technical advance allowed visualization of the angioarchitecture of the malformations and let the surgeons to make a preoperative plan to approach the lesion (9, 10).

Doppman, Di Chiro and Ommaya in 1968 reported the first successful endovascular obliteration of a spinal AVM (9).

In 1969 Krayenbuhl and Yasargil published their experience in treating these lesions with microsurgical techniques. In the case of the spinal dural AVFs they proposed to strip the dilated venous system of the cord (23, 36).

In 1977 after Kendall and Logue, the spinal dural AVFs were classified as a separate disease from the other group of “true spinal AVMs”. At surgery they only treated the site of the fistula at the dura without disturb the dilated perimedullary veins with good postoperative results (21).

Later in 1980 Merland et. al. in coincidence with this concept reported these lesions as “radiculomeningeal arteriovenous fistulae” suggesting that arteriovenous fistulas constitute the majority of retromedullary malformations (27, 28).

Heros in 1986 described a new type of spinal AVM, a direct fistula between the anterior spinal artery and a vein, anterior to the cord, classified as type IV by Anson and Spetzler (4, 18).

Rosenblum et. al. in 1987 examined 81 cases of spinal AVMs and concluded that dural AVMs are acquired entities whereas intradural AVMs are congenital lesions (32).

The case reported in 1998 by Yoshino provides indirect evidence of the acquired origin of the disease in a case of a previous normal myelogram but it is difficult to establish a relationship between an uncomplicated surgery and the later development of a spinal AVF (37).

Several pathogenic mechanisms were proposed to explain the development of spinal dural AVFs, trauma, inflammation, infection and others but no one could be verified. The case presented here may explain this on the basis of the inflammatory changes and or venous thrombosis due to vertebral tuberculosis occurring around the root involved in the fistula (1, 7, 15, 16, 17, 19, 20, 22, 26, 29, 32, 34, 35).

The author presents a case with a direct relation between a previous disease, spinal tuberculosis, and the later development of myelopathy secondary to venous hypertension from a spinal dural AVF at the same level.

REFERENCES

  1. Aminoff MJ, Barnard RO, Logue V: The pathophysiology of spinal vascular

malformations. J Neurol Sci 23:255-263, 1974

  1. Aminoff MJ, Logue V: Clinical features of spinal vascular malformations.

Brain 97:197-210, 1974

  1. Aminoff MJ, Logue V: The prognosis of patients with spinal vascular

malformations. Brain 97:211-218, 1974

  1. Anson JA, Spetzler RF: Classification of spinal arteriovenous malformations

and implications for treatment. B.N.I. Q. 8:2, 1992

  1. Baker HL Jr., Love, JG, Layron DD Jr.: Angiographic and surgical aspects

of spinal cord vascular anomalies. Radiology 88:1078, 1967

  1. Berenbruch K: Ein Fall von Multiplen Angiolipomen kombiniert mit einem

Angiom des Rückenmarks. Inauguraldissertation, Tübingen, 1890

  1. Berenstein A, Lasjaunias P : Spine and spinal cord vascular lesions.

Endovascular Treatment of Spine and Spinal Cord Lesions (Surgical

Neuroangiography, Vol 5). Berlin, Springer-Verlag, 1992, p1

  1. Brasch F: Über einen schweren spinalen Symptomenkomplex, bedingt

durch eine aneurysma-serpentinumartige Veränderung eines Theils der

Rückenmarksgefässe. Berl Klin Wochenschr 37:1210, 1900

  1. DiChiro G, Doppman JL, Ommaya AK: Radiology of spinal cord

arteriovenous malformations. Prog Neurol Surg 4:329-354, 1971

  1. Djindjian R, Hurth M, Hondart R: L’Angiographie de la Moelle Epinière.

Paris, Masson, 1970

  1. Ellsberg CA : Surgical significance and operative treatment of enlarged and

varicose veins of the spinal cord. Am J Med Sci 151 :642-652, 1916

  1. Foix CH, Alajouanine TH: La myélite necrotique subaigue: Myélite centrale

angéio-hypertrophique à évolution progressive: Paraplegie amyotrophique

lentement ascendante, d’abord spasmodique, puis flasque,s’accompagnant

de dissociation albumino-cytologique. Rev Neurol 33:1-42, 1926

  1. Gaupp J: Hämorrhoiden der Pia mater spinalis im Gebiet des

Lendenmarks. Beitr Pathol 2:516, 1888

  1. Gebhardt F: Über das Verhalten der Reflexe bei Querdurchtrennung des

Rückenmarks. Dtsch Z Nervenh 6:127, 1895

  1. Grote EH, Bien S : Arteriovenous malformations of the spinal cord.

Youmans JR, (ed) : Neurological Surgery, ed 4. Philadelphia, WB

Saunders, 1996, pp 1511-1530

  1. Grote EH, Voigt K: Clinical syndromes, natural history, and pathophysiology

of vascular lesions of the spinal cord. Neurosurg Clin N Am 10:17-45, 1999

  1. Hassler W, Thron A, Grote EH: Hemodynamics of spinal dural

arteriovenous fistulas. J Neurosurg 70:360-370, 1989

  1. Heros RC, Debrun GM, Ojemann RG, Lasjaunias PL, Naessens PJ. Direct

spinal arteriovenous fistula: A new type of spinal AVM. J Neurosurg

64:134-139, 1986

  1. Huffmann BC, Gilsbach JM, Thron A : Spinal dural arteriovenous fistulas:

plea for neurosurgical treatment. Acta Neurochir (Wien) 135:44-51, 1995

  1. Hurst RW, Kenyon LC, Lavi E, Raps EC, Marcotte P: Spinal dural

arteriovenous fistula: the pathology of venous hypertensive myelopathy.

Neurology, 45:1309-1313, 1995

  1. Kendall BE, Logue V: Spinal epidural angiomatous malformations draining

into intrathecal veins. Neuroradiology 13:181-189, 1977

  1. Kohno M, Takahashi H, Yagishita A, Haisa T, Segawa H: Preoperative and

postoperative magnetic resonance imaging (MRI) findings of radiculomeningeal arteriovenous malformations: important role of gravity in

the symptoms and MRI. Surg Neurol, 48:352-356, 1997

  1. Krayenbühl H, Yasargil MG, McClintock HG: Treatment of spinal cord

vascular malformations by surgical excision. J Neurosurg 30:427-435,

1969

  1. Malis LI: Arteriovenous malformations of the spinal cord. Youmans JR, (ed):

Neurological Surgery. ed 2. Philadelphia, WB Saunders, 1982, pp 1850

-1874

  1. Marsh WR: Vascular lesions of the spinal cord: history and classification.

Neurosurg Clin N Am, 10:1-8, 1999

  1. McCutcheon IE, Doppman JL, Oldfield EH : Microvascular anatomy of dural

arteriovenous abnormalities of the spine: a microangiographic study.

J Neurosurg, 84:215-220, 1996

  1. Merland JJ, Riché MC, Chiras J: Les fistules artério-veineus intra-

canalaires, extra-médullaires à drainage veineux medullaire.

J Neuroradiol 7:271-320, 1980

  1. Merland JJ, Assouline E, Rüfenacht D: Dural spinal arteriovenous

fistulae draining into medullary veins: Clinical and radiological results of

treatment (embolization and surgery) in 56 cases. Valk, J (ed):

Neuroradiology 1985/1986. Amsterdam, Elsevier Science, 1986, pp. 283-

289

  1. Morgan MK, Marsh WR: Management of spinal dural arteriovenous

malformations. J Neurosurg 70:832-836, 1989

  1. Perthes, G: Über das Rankenangiom der weichen Häute des Gehirns und

Rückenmarks. Dtsch. Z. Chir 203:93, 1927

  1. 31. Puusepp L : Zur frage der varices spinales und ihrer operativen. Therapie

Zbl Neurochir 3:158-169, 1938

  1. Rosenblum B, Oldfield EH, Doppman JL, Di Chiro G: Spinal arteriovenous

malformations: A comparison of dural arteriovenous fistulas and intradural

AVMs in 81 patients. J Neurosurg 67:795-802, 1987

  1. Sargent P: Haemangioma of the pia mater causing compression

paraplegia. Brain 48:259, 1925

  1. Symon L, Kuyama H, Kendall B: Dural arteriovenous malformations of

the spine: Clinical features and surgical results in 55 cases

J Neurosurg 60:238-247, 1984

  1. Wyburn-Mason R: The Vascular Abnormalities and Tumours of the Spinal

Cord and Its Membranes. London, Henry Kimpton, 1943

  1. Yasargil MG: Surgery of vascular lesions of the spinal cord with the

microsurgical technique. Clin Neurosurg 17:257-265, 1970

  1. Yoshino O, Matsui H, Hirano N, Tsuji H : Acquired dural arteriovenous

malformations of the lumbar spine. Neurosurgery 42 :1387-1389, 1998

FIGURE LEGENDS

Figure 1a : Sagital T2-weighted MRI shows the secuelae of the spinal tuberculosis at L2-L3 vertebral bodies and multiple serpentine flow voids between the roots of the cauda equina and around the cord.

Figure 1b : Axial T2-weighted MRI at L2 level where the intradural coiled vascular images are clearly seen.

Figure 2a : Digital Angiography without substraction. Front view of a selective injection of the left L2 radiculomeningeal artery with the shunt at the level of the neuroforamen and early filling of the arterialized perimedullary vein.

Figure 2b : Digital Angiography with substraction. Front view of a later phase showing the dilated vein, a pseudoaneurysm and the normal coronary venous plexus of the cord.

Figure 2c : Digital Angiography with substraction, front view at midthoracic level showing the filling of the whole perimedullary venous system through the spinal dural AVF.

Figure 3a : Operative photograph. Under the operating microscope the dura is opened at L2 level, the left L2 root is dissected medially and the venous part of the fistula becomes visible entering the neuroforamen. On the left, a cottonoid is keeping away the vessel from the roots of the cauda equina. For orientation, up is left and right is caudal.

Figure 3b : Once the dilated vessel is dissected free along 25 mm. a temporary clip is placed near the neuroforamen.

Figure 3c : After changed both color and turgor of the intradural part of the fistula, the clip is removed and the vessel (hanged with a dissector in the figure), is coagulated along 10 mm.

Figure 3d : Once coagulated, the vessel is cut. The distal (intradural) cut end of the fistula is retracted with a ball tip dissector.

Figure 4 : Postoperative sagital T2-weighted MRI without the intradural coiled vascular images. Artifacts due to the titanium sublaminar wires are seen back to T11-T12 and L4-L5.

Figure 5 : The patient forty eight months after the surgery is free of lumbar pain, can walk aided with cans, needs intermittent catheterism of the bladder but regained the control of the bowel.

The origin of Spinal Dural Arteriovenous Fistulas

Literature Review and Case Report.

Author : Gabriel Jungberg M.D.

Featured Posts
Recent Posts
Archive
Search By Tags
No hay tags aún.
Follow Us
  • Facebook Basic Square
  • Twitter Basic Square
  • Google+ Social Icon
bottom of page