Association of venous varix and developmental venous anomaly: report of a case and review of literature

Abstract

Cerebral developmental venous anomalies (DVAs) are the most frequently encountered cerebral vascular malformation. Most are asymptomatic and incidentally detected. Here we present a case of DVA associated with venous varix presented with chronic headache. A 50-year-old woman presented with right hemicranial headache since 6 months. There was no neurological deficit. MRI showed a well-defined oval T2 hyperintense, T1 isointense extra-axial lesion in the right parietal region showing intense homogeneous enhancement. Prominent vascular flow void was extending from the lesion up to the deep parietal white matter. Subtle thin linear areas of blooming noted in the parietal white matter converging towards the vascular flow void. The venous sac is in communication with the cortical vein draining to the superior sagittal sinus. These MRI findings favoured a diagnosis of DVA in the right parietal lobe with prominent draining vein forming a cortical venous varix. The patient was managed conservatively with symptomatic treatment for headache.

Background

Cerebral developmental venous anomalies (DVAs) are the most frequently encountered cerebral vascular malformation. Most of them are asymptomatic and observed incidentally during routine CT and MRI studies. Most common vascular anomaly associated with DVA is cavernous malformation. Rarely DVAs are found in association with AV fistula.¹ DVA associated with cerebral venous aneurysm is very rare, only few cases have been reported. Here we present a case of DVA associated with venous varix presented with chronic headache.

Case presentation

A 50-year-old woman presented with headache since 6 months. The right hemicranial headache was throbbing in nature. There was no neurological deficit. There was no family history of migraine.

Investigations

In view of late onset headache, an MRI was done for further evaluation. The MRI revealed a well-defined oval T2 hyperintense extra-axial lesion of size 10×8 mm in the right parietal region. The lesion appears isointense on T1 weighted image (T1WI) (figure 1A,B). Prominent vascular flow void was extending from the lesion up to the deep parietal white matter. Subtle thin linear areas of blooming noted in the parietal white matter converging towards the vascular flow void (figure 2A,B). Post contrast T1WI shows intense homogeneous enhancement of the right parietal extra-axial lesion and enhancement of the prominent vessel communicating to it (figure 1C). Tiny enhancing vascular twigs were also noted in the deep right parietal white matter corresponding to the region of blooming on susceptibility weighted imaging (SWI). Maximum intensity projection obtained from post contrast three dimensional T1WI showed contrast filled outpouching in continuation with a parenchymal draining vein, corresponding to the region of DVA. The venous sac is in communication with cortical vein draining to the superior sagittal sinus (figure 2C). No mass effect noted over the adjacent brain parenchyma. These MRI findings favoured a diagnosis of DVA in the right parietal lobe with prominent draining vein forming a cortical venous varix.

Figure 1.

Axial T2W MRI of brain (A) shows well-defined hyperintense extra-axial lesion in the right parietal region. The lesion appears isointense on T1WI (B) and showing intense homogeneous enhancement on post contrast T1WI (C).

Figure 2.

Susceptibility weighted image demonstrates subtle thin linear areas of blooming converging in the parietal white matter (A). Prominent vascular flow void noted on axial T2 weighted image (T2WI) (arrowhead in B) extending from the area of blooming. Maximum intensity projection obtained from post contrast three-dimensional T1WI shows contrast filled venous varix in continuation with a parenchymal draining vein, corresponding to the region of developmental venous anomaly. The varix is communicating to the superior sagittal sinus by a cortical vein (C).

Treatment

The patient was managed conservatively with symptomatic treatment for headache.

Outcome and follow-up

The patient had no complaint after 3 months follow-up.

Discussion

DVAs are the most commonly encountered cerebral vascular malformations. These are malformations of venous structures without abnormality of the capillary or arterial structures. DVAs are comprised of enlarged medullary veins that drain into a collector vein resulting in a ‘caput medusa’ appearance on imaging. This dilated collector vein either penetrates the cortex to drain superficially to cortical veins or deeply to subependymal veins of the lateral ventricle and then into the deep venous system.¹ From the location and size of DVA it is difficult to predict whether to superficial or deep vein the DVA would join.²

Most of the patients with DVA are usually asymptomatic and it is found incidentally. As these vessels drain normal cerebral parenchyma, thrombosis of collecting vein may present as haemorrhagic infarct.¹ Associated cavernous malformations may be associated with DVAs in 13%–40% of cases and present as haemorrhage or seizure. It is usually the cavernous malformation that is responsible for haemorrhage, not the DVA.³ T1 and T2W MRI shows flow void in the medullary vein or draining vein depending on size. T2WI may show small twigs of vascular flow void converging into a draining vein. SWI is highly sensitive for detection of DVAs due to presence of deoxygenated venous blood. On SWI, DVA appear as hypointense venous channels with large collecting veins due to the high amount of deoxygenated venous blood within the slow flowing veins.⁴

In our case, the DVA is small and faintly seen as linear hyperintensity on T2WI, but clearly seen only in SWI as small linear areas of blooming that is extending along the collector vein. Occasionally on MR imaging, T2 hyperintensity may be seen in the region of a DVA. This may occur in asymptomatic patients, but can also reflect acute oedema from thrombosis or gliosis from chronic outflow obstruction. Post gadolinium study shows enhancement of the venous angioma and the draining vein.¹

CT and MRI can demonstrate the typical caput medusae draining into a collecting vein, allowing confident diagnosis of DVAs without the need to obtain digital subtraction angiography (DSA). In DSA, DVAs typically opacify during the venous phase of the angiogram. DSA is the best imaging modality to study the haemodynamic behaviour of DVAs and is performed in patients presenting with ischaemic or haemorrhagic complications or whenever an associated vascular malformation is suspected on CT or MRI.¹

A cerebral varix is usually identified as a mass showing a flow void; however, there may be no signal void with any of the pulse sequences due to the slow flow within the varix.⁵

In the present case, the varix was isointense on T1WI and predominantly hyperintense on T2 except for a small focus of flow void at the communication with the collector vein.

Most of these lesions remain asymptomatic. However associated locoregional brain atrophy, white matter lesion, cavernous malformation, dystrophic calcification and parenchymal haemorrhage have been described.³

DVAs are replaced vessels most likely to compensate for absence of a portion of cerebral venous system. Resection of such lesions can result in venous infarct in the brain parenchyma drained by DVA. So conservative management is recommended for DVAs unless complicated by haemorrhage.¹

In patients of DVA associated with cavernous angioma, risk of haemorrhage is attributed to the cavernous angioma rather than DVA. So the cavernous angioma should be treated surgically preserving the DVA.¹

There are 14 reported cases of DVA associated with venous varix in English literature, details of which have been summarised in table 1.

Table 1.

Details of the reported cases of venous varix associated with DVAs

SI no	Author and year of publication	Age/sex	Clinical presentation	Location of DVA	Location of varix	Diagnosis	Management
1	Meyer et al 19836	31/F	Right frontal headache	Right frontoparietal	insular	CT, angiography	Conservative
2	Handa et al 19847	24/M	Incidental. Scanning done for trauma	Right frontoparietal	Deep in right cerebral hemisphere, thalamostriate	CT, angiography	Conservative
3	Namaguchi et al 19868	6/F	Frontal headache, reduced visual acuity	Right frontoparietal	Cortical in right parasagittal region	CT, angiography	Conservative
4	Dross et al 19879	62/F	Aphasia and right hemiplegia due to infarct in right basal ganglia and internal capsule. DVA and varix found incidentally.	Left frontal	Anterior septal, in the region of foramen of Monro.	CT, angiography	Conservative
5	Maiuri et al 199010	18/F	Intracranial haemorrhage	Left temporal	cortical	CT, angiography	Giant aneurysm. Surgically treated
6	Uchino et al, 19955	23/M	Headache	Right frontoparietal	cortical	CT, MR, angiography	Conservative
7	Kars et al 200011	9/F	Decrease scholastic performance	Thalamus	Galen	CT, MR, angiography	Conservative
8	Vattoth et al 200512	14/F	Two episodes of generalised seizure	Bilateral frontal	Right middle cerebral vein	CT, angiography	Conservative
9	Sirin et al 200813	13/F	Two brief episodes of absent seizure	Left temporal	Left middle cerebral vein	CT, MR, angiography	Conservative
10	Nakajima et al 201214	67/F	Tinnitus and hypoacusis	Right cerebellum	Right cerebellar cortical	MRI, angiography	Conservative
11	Nakajima et al 201315	74/F	Postoperative case of carcinoma left breast. Incidentally detected DVA	Left frontoparietal	Left frontal cerebral	CT, MR	Conservative
12	Watanabe et al 201416	15/M	Incidental. Scanned for accidental trauma	Left frontal	cortical	CT, MRI, angiography	Conservative
13	Shim 201417	35/M	Occasional headache and dizziness	Left frontal	Left middle cerebral vein	MRI, angiography	Surgical
14	Xu et al 201718	21/F	Incidentally detected DVA after imaging for accidental trauma	Left cerebral hemisphere	Vein of Galen	MRI, angiography	Conservative
15	Present case	50/F	Headache 6 months	Right parietal	cortical	MRI	Conservative

DAV, developmental venous anomaly; F, female; M, male.

Out of 14 reported cases, 12 undergone conservative treatment and had a benign course on follow-up.^5–18 One case of giant varix presented with haemorrhage and underwent surgery. Case reported by Shim et al underwent surgery even without haemorrhage and had uneventful follow-up.

Detection of DVA and venous varix are incidental and it’s natural course is uneventful in mostly reported cases. These patients need regular clinical follow-up, and if there is change in character of headache, increased frequency of seizure and focal neurological deficit requires repeat imaging. Surgery or alternative treatment is only recommended if bleeding has occurred.¹

Learning points.

• Developmental venous anomalies (DVAs) are the most commonly encountered cerebral vascular malformations. Association of DVA with venous varix is very rare.

• DVAs are replaced vessels most likely to compensate for absence of a portion of cerebral venous system. Resection of such lesions can result in venous infarct in the brain parenchyma drained by DVA.

• Identification of varix and knowledge about natural course of these lesions are important to prevent unnecessary intervention.