:Acta-v-:-. Ndurochlrurgica Acta Neurochir (Wien) (1993) 120:33-39 9 Springer-Vertag 1993 Printed in Austria Cerebral Venous Angiomas: Surgery as a Mode of Treatment for Selected Cases V. Lupret 1, L. Negovetic 1, D. Smiljanic 1, Z. Klanfar 2, and S. Lambasa 3 Departments of Neurosurgery 1, Radiology 2, and Pathology 3, Clinical Hospital "Sestre Milosrdnice", Zagreb, Croatia Summary Eleven patients with venous angiomas, 6 males and 5 females ranging in age from 4 to 58, are presented. Four patients presented with intraeerebral haematoma and 3 patients had associated cavernous angioma, respectively. Patients with intracerebral haematoma had signs and symptoms due to the localication of the haematoma. The other patients presented with headache, seizures, vertigo, ataxia and mental disturbances. Pre-operative diagnosis was based on computerized tomography, magnetic resonance imaging and cerebral angiography. In 9 surgical cases it was confirmed by histopathological examination of operative specimens. After establishing the type, size and location &the lesion decision for operative treatment was made in nine cases, in four of them because of the presence of an intracerebral haematoma and in 5 of them due to severe disability. Eight of these 9 patients recovered completely and one improved. No severe cerebral oedema was encountered after converging medullary veins were excised and main draining veins partially coagulated. In this small series we encountered an unexpectedly large percentage of venous angiomas causing intracerebral haemorrhage which are commonly considered more benign than other vascular malformations. After reviewing previously reported cases of venous angiomas causing intracerebral haemorrhage and severe neurological deficit we think that the term "benign" is worth reconsidering. We propose a thorough examination of each case of venous angioma and the operative treatment when appropriate taking into account patients state and location of angioma. Keywords." Venous angioma; vascular malformation; cerebral haemorrhage. Introduction Venous malformations (angiomas) represent today a well defined subgroup of cerebral vascular malformations together with arteriovenous angiomas, cavernous angiomas and capillary tclcangicctasias 2' 12, 17, 26 Venous angiomas consist of several dilated medullary vains arranged radially and converging into a central draining vein and intervening neural parenchyma. The central draining vein joins either one of the superficial cortical veins or subepedymal veins 12' 17, 26 Histopathologically these lesions consist of dilated vessels with thickened walls with absence of smooth muscle and elastine fibres and intact neural tissue 12' 17, 26. In some reports haemosiderin stained gliosis and calcifications were found confirming previous haemorrhage16, 2s. Venous angiomas can be found supratentorially and infratentorially. They are located usually in frontal lobes and cerebellum and less frequently in occipital, temporal and parietal lobes, basal ganglia and brainstem 6, 10, 11, 12, 17, 22 The angiographic appearance of several radially composed dilated veins draining into a central "truncus" of large caliber is the reason for the commonly used comparison with "caput medusae ''1~ 11, 16, 18--20, 22 Since the introduction of computerized tomography (CT) venous angiomas are much more frequently reported 1, 9, 10, 22. Contrast enhanced CT shows linear hyperdensity (corresponding to central draining vein) or globular area of irregular hyperdensity (possibly corresponding to radially composed medullary veins, sometimes with areas of haemosiderosis and calcifications)9, 16, 22, 26. The role of magnetic resonance imaging (MR) has been recently pointed out because of the typical appearance of "cord like" hypo-intensity and sometimes a globular area of mixed hypo-intensity and hyperintensity 5' 13, 21, 2s Clinical presentation of venous angiomas located supratentorially includes seizures, and headaches as 34 v. Lupret et al.: Cerebral Venous Angiomas: Surgery as a Mode of Treatment m o s t c o m m o n , a n d dizzines, m e n t a l d i s t u r b a n c e s , speech i m p a i r m e n t , m o t o r w e a k n e s s as less c o m m o n s y m p t o m s 1, 8, t2, 26. I n f r a t e n t o r i a l l e s i o n s p r e s e n t m o s t f r e q u e n t l y w i t h gait d i s t u r b a n c e s a n d a t a x i a 16' 20. Although in some autopsy reports venous angiomas r e p r e s e n t a h i g h p e r c e n t a g e o f all v a s c u l a r m a l f o r m a t i o n s , their clinical r e l e v a n c e is still n o t c l e a r e d u p ~5' 23. A s far as we k n o w a r o u n d 200 cases are r e p o r t e d i n clinical trials. M a n y o f t h e m h a v e b e e n r e p o r t e d as incidental findings or with minor neurological disturb a n c e s 1, 10, 12, 14, 23. A t the s a m e t i m e a s i g n i f i c a n t incidence of venous a n g i o m a s causing h a e m o r r h a g e r a n g i n g f r o m 16 to 4 3 % c a n b e f o u n d i n a d d i t i o n to t h o s e c a u s i n g severe n e u r o l o g i c a l s y m p t o m s 8-10, 16, 22, 26 T h e m o d e o f t r e a t m e n t is still c o n t r o v e r s i a l . S o m e a u t h o r s c o n s i d e r v e n o u s a n g i o m a s m o r e b e n i g n lesions than other vascular malformations and propose nono p e r a t i v e t r e a t m e n t w i t h f o l l o w u p ~' ~5, 1~. O t h e r s suggest t h a t these lesions s h o u l d n o t b e c o n s i d e r e d t o t a l l y b e n i g n d u e to s i g n i f i c a n t n u m b e r o f r e p o r t e d cases w i t h h a e m o r r h a g e a n d severe n e u r o l o g i c a l d i s t u r b a n c e s a n d p r o p o s e o p e r a t i v e t r e a t m e n t 9-1~, 16 Clinical Material and Methods Eleven patients harbouring venous angioma are presented in Table 1, The first author has operated upon 9 patients and 2 were treated conservatively. There were six males and five females ranging in age from 4 to 58. Four patients (Cases 1, 2, 6, and 9) had intracerebral haemorrhage and signs and symptoms due to its location. Other patients presented mostly with headache and seizures. The patient with infratentorially located lesion presented with vertigo, ataxia and left hemiparesis. Lesions were situated in frontal lobe4, parietal lobe2, basal ganglia2, temporal lobe1, occipital lobeI and fight cerebellar hemisphere~.Three patients had associated cavernous angioma confirmed histologically (Cases 3, 5, 11). Radiological findings are presented in Table2. Contrast enhanced C T showed linear hyperdensity in 2 cases, a globular or roundish area in 5 and homogenous hyperdensity in 4 cases revealing intracerebral haematoma with no signs of the underlying lesion (Cases 1, 2, 6 and 9). MRI was obtained in 8 cases showing linear hypo-intensity sometimes with additional lobular area of mixed intensity and linear hypo-intensity with round area of mixed intensity sorrounded by a thin hypo-intensity zone in 3 cases with associated cavernous angioma. Cerebral angiography was obtained in 8 cases. Decision for operative treatment was made due to disabling neurological signs and symptoms in Cases 3, 5, 8, 10 and 11 and due to space occupying intracerebral haematoma in Cases 1, 2, 6 and 9. Intra-operatively great care was taken to extirpate the whole lesion in order to submit a complete specimen to the pathologist to avoid Table I. Clinical Presentation of Venous Angiomas and Accompanying Lesions Patient no. Age Sex Signs and symptoms/ onset, duration Location Accompanying lesion Operation 1 4 F yes 15 M none yes 3 18 M 21 F cavernous angioma none yes 4 5 24 M 6 25 M 7 31 F 8 32 M 9 34 F 10 34 M fight occipital lobe right temporal lobe fight frontal lobe basal ganglia fight right parietal lobe left frontal lobe basal ganglia left right frontal lobe right frontal lobe right cerebellar hemisphere none 2 partial seizures/ 1 month progressive left hemiparesis/abrupt headache, seizures/ 6 months headache, mild left hemiparesis/2 months headache, seizures/ 2 months right hemisparesis/ abrupt fight hemiparesis/ abrupt headache, occasional vertigo/10 years headache, vomiting/ abrupt headache, ataxia, vertigo, left hemiparesis/abrupt headache, nausea, vomiting/abrupt left parietal lobe 11 58 F no cavernous angioma none yes none no none yes none yes none yes cavernous angioma yes yes 35 V. Lupret et al.: Cerebral Venous Angiomas: Surgery as a Mode of Treatment Table 2. Results of Radiological Examination for 11 Patients in this Series Patient Computerized tomography Magnetic resonance imaging Angiography no. 1 Irregular hyperdense area (ICH) Round hyperdense area 2 / / / / (ICH) 3 Globular area of mixed density Linear hyperdensity 4 5 6 7 8 9 I0 11 Globular hyperintensity area curvilinear mild-density area Linear hypo-intensity sorrounded with small area of hyperintensity Several linear hypo-intensity zones globular hyperintensity area / Globular hyperdensity area Irregular hyperdense area (ICH) Round area of mixed density Linear hyperdensity Globular area of hypo-intensity with spot-like hyperint, zones Linear hypo-intensity Roundish area of mixed density (ICH) Globular area of mixed density Globular hyperdensity area Round area of hyperintensity with tyo round hypo-intensity zones Globular area of hypo-intensity with spot-like hyperint, zones Curvilinear hypo-intensity with lobular mixed intensity area typical typical typical typical typical typical typical typical / ICH = intracerebral haematoma; typical = radially composed dilated medulary veins converging into cerebral draining vein. Fig. 1. Case 8. Contrast CT scan showing linear hyperdensity parasagitally in the right frontal lobe Fig. 2. Case 8. Coronal Tx-weighted MRI showing linear hypointensity zone in the right frontal lobe the possibility of not recognising another accompanying vascular malformation or tumour (which proved to be the case in cases 3, 5, and 11). Three patients are chosen for detailed presentation together with radiological findings. cause of personality changes and suicidal intentions. After one suicidal attempt he underwent CT and after contrast administration linear hyperdensity was found in the right frontal lobe (Fig. 1). MRI showed typical tubular-shaped signal-void area (Fig. 2.) and cerebral angiography revealed typical findings described as "caput medusae" (Fig. 3). A decision was made for operative treatment due to severe difficulties the patient was suffering from. All medullary veins were excised and central trunk partially coagulated. During four months of follow-up the patients suffered no further headaches. Case 8 A 32-year-old man suffered for ten years from severe headaches and occasional vertigo. He was under psychiatric surveillance be- 36 V. Lupret etal.: Cerebral Venous Angiomas: Surgery as a Mode of Treatment Case 9 A 34-year-old female had abrupt onset of headache and vomiting, followed by somnolence. Contrast enhanced CT on admission showed a round area of mixed density in the right frontal lobe with irregular hyperdense area parasagittally (Fig. 4). MRI revealed a round are of hyperintensity with two smaller round hypo-intensity zones (Fig. 5). The patient was operated on by another neurosurgeon and after partial removal of the haematoma a convolution of large vessels was encountered and the operation stopped at that point. Postoperative angiography revealed several dilated medullary veins divided into two groups and draining into two central trunks which joined one cortical vein draining into the superior sagittal sinus (Fig. 6). Since the patient's clinical condition did not improve she was operated upon by the first author and total excision of the medullary veins with coagulation of the central trunks, one totally and one partially, was accomplished. Postoperative course was uneventful and the patient recovered completely. Case 3 An 18-year-old man was involved in a car accident some 18 months prior to admission. Skull radiographs showed no bony injury and he was discharged from hospital. One year later epileptic seizures and severe headaches occurred. He was admitted 6 months after the occurrence of seizures. Contrast enhanced CT showed globular mass of mixed density in the right frontal lobe (Fig. 7). MRI revealed globular area of mixed, predominantly high intensity and more medially a curvilinear lesion of mild intensity (Fig. 8). Typical appearance of venous angioma was obtained by angiography (Fig. 9). IntraFig. 3. Case 8. Cerebral angiogram showing several dilated medullary veins converging into one central vein draining into the superior sagittal sinus Fig. 4. Case 9. Contrast CT scan showing round area of mild density in the right frontal lobe and irregular hyperdensity parasagittally Fig. 5. Case 9. Tl-weighted MRI showing round high intensity mass presenting with an intracerebral haematoma and two round areas of hypo-intensity (horizontal section of two dilated central draining veins Fig. 6. Case 9. Cerebral angiogram (taken after first surgical attempt) revealing several dilated medullary veins draining into two central veins that join and drain into the superior sagittal sinus Fig. 7. Case 3. Contrast CT scan revealing globular area of mixed, spot-like hyperdensity and hypodensity in the posterior part of the frontal lobe V. Lupret etaI.: Cerebral Venous Angiomas: Surgery as a Mode of Treatment 37 central trunk distally. We have chosen this strategy considering that venous angiomas may be the result of a compensatory mechanism for occlusion of other vessels during embryonic development and that these lesions can possibly be considered as instances of anomalous venous drainage 2' 18, 20, 25 Fig. 8. Case 3. Coronal Tl-weighted MRI showing area of mixed, predominantly high intensity and curvilinear area of mild intensity situated more medially Fig. 9. Case 3. Cerebralangiogram, A-P view,showing radiallycomposed medullaryveinsjoining centraldraining vein and draining into deep subependymalveins operatively two adjacent lesions were found- a cavernous angioma situated more laterally and a venous angioma medially (later confirmed by histological examination of two specimens). The patient recoveredcompletelyand has remained asymptomaticin the followup period of two years. Discussion The strategy in all surgical cases was to coagulate and remove dilated medullary veins and partially coagulate the central draining trunk thus leaving drainage of other veins of normal caliber intact, which join the Theoretically, cerebral oedema could occur after removal of a venous angioma because of abrupt cessation of venous drainage and was reported in a few cases 14. With the afore-mentioned operative strategy and adequate pre-operative and postoperative medication we encountered no cerebral oedema causing postoperative morbidity. We have found the results of operative treatment satisfactory. 8 patients are asymptomatic during follow-up and one patient is left with right hemiparesis, but independent. Five of them were submitted to surgery due to disabling deficits and the postoperative course proved this decision to be appropriate. When modes of treatment for venous angiomas are discussed, neurological signs and symptoms, that can occasionally be very disabling to patients, are sometimes neglected in favour of intracranial haemorrhage as the sole indication for operative treatment. Garretson stated about seizures secondary to arteriovenous malformations that they become more resistant to medical treatment with the age of time 4. This is also true of seizures secondary to venous angiomas. Even intracranial haemorrhage as the sole indication for operative treatment is questioned. The most commonly cited work in favour of venous angiomas being benign lesions is the one by Sarwar and McCormick published in 1978. The fact is revealed that venous angiomas compose 60% of all vascular malformations found in autopsy reports. These findings compared to the relatively small number of clinically reported cases, could lead to the conclusion that these lesions are clinically insignificant and thus relatively benign 19. At the time this conclusion was reached, only 14 cases of venous angiomas had been reported in clinical series and 4 of them (28.5%) presented with intracranial haemorrhage 9. In the past decade the incidence of intracranial haemorrhage associated with venous angiomas has been reported as ranging from 16 to 29% and in some reports even as high as 43% 8- a0, 16, 22, 26. The question can be raised whether intracranial haemorrhage can occur at relatively low venous pressure. J. R. Little et al. measured haemodynamic characteristics of cavernous angiomas during surgery and found relatively low driving pressures 7. And yet these lesions are known to be able to 38 V. Lupret et al.: Cerebral Venous Angiomas: Surgeryas a Mode of Treatment bleed. Such investigations have not been designed for venous angiomas yet, but similar results could be expected. In a long-term clinical study on arteriovenous malformations of the brain Forster et al. stated that " . . . the advantages of surgery do not become apparent until the mean period of follow-up approaches 10 years but become increasingly evident with the further passage of time ''3. In their report on the natural history of venous malformations Rigamonti et al. review their experience with 30 patients and the mean follow-up period was 45 months is. Eighteen patients with supratentorial (compared to our 10 patients) and 12 patients with infratentorial venous angiomas were followed up for between 18 and 104 months. Five of these patients were symptomatic at the time of reporting, none of them harbouring rebleeding or acute episodes of neurological dysfunction. In conclusion Rigamonti et al. recommended a thorough search for accompanying lesions (tumours, cavernous angiomas) causing signs and symptoms that could be erroneously attributed to venous angiomas (which by no means is indicated). But it was not documented which pathophysiological findings or characteristics underly the statement that cavernous angiomas can be the cause of bleeding and venous angiomas can not, considering that both lesions are characterized by low blood flow velocities. The clinically reported incidence of haemorrhage for cavernous and venous angiomas is 2 0 - 2 5 % and 1 6 - 43 %, respectively (explaining every haemorrhage associated with venous angioma with present unrecognized accompanying lesion is statistically unacceptable). In our series three patients had accompanying cavernous angiomas but none of these were associated with haemorrhage. In his review article on the natural history of intracranial vascular malformations R. H. Wilkins has stated that venous angiomas may be discovered incidentally or may present with bleeding and that according to data available at that time, mostly relying on the report of Rothfus et al16: " . . . surgical treatment is more of a consideration for cerebellar venous angiomas than for cerebral venous angiomas...-23 The natural history of venous angioma is uncertain with regard to the risk of spontaneous haemorrhage and as well as that of recurrent haemorrhage due to the small number of cases sofar diagnosed during life. Most of clinical reports, including ours, deal with small numbers which make any firm conclusions about the mode of treatment highly questionable. Therefore, we recommend thorough examination of each case of venous angioma and surgical excision of all dilated medullary veins and partial coagulation of the central draining vein when appropriate taking into account the patient's clinical condition, severity of signs and symptoms and accessibility the lesion. 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Wilms G, Marehal G, Van Hecke P, Van Fraeyenhoven L, Decrop E, Baert AL (1990) Cerebral venous angiomas. MR imaging at 1.5 ~esla. Neuroradiology 32:81-85 25. Ya~argil MG (eds) (1987) Microneurosurgery, Vo13 A. Thieme, New York, pp 49-57 26, Ya~argil MG (eds) (1987) Microneurosurgery, Vol 3 B. Thieme, New York, pp406-438 Correspondence and Reprints: Velimir Lupret, M.D., Department of Neurosurgery, Clinical Hospital "Sestre Milosrdnice", Vinogradska 29, 41000 Zagreb, Croatia.