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Dural sinus hypertension due to segmental stenosis
European Journal of Radiology Extra 53 (2005) 91–93
Dural sinus hypertension due to segmental stenosis Kuo-Lun Huanga , Yeu-Jhy Changa,∗ , Chi-Jen Chenb b
a Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University, 199, Tung Hwa North Road, Taipei, Taiwan Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Chang Gung University, 199, Tung Hwa North Road, Taipei, Taiwan
Received 6 August 2004; received in revised form 20 December 2004; accepted 23 December 2004
Abstract We report a rare case with dural sinus hypertension due to segmental stenosis, associated with leptomeningeal angiomatosis and drainage from the diploic veins. The etiology and natural history still remain unknown. To differentiate dural sinus stenosis from the sinus thrombosis, the computed tomography venography appears to be a better tool than the other vascular imaging studies including the digital subtraction angiography in such a case. Dural sinus stenosis should be a differential diagnosis for patients with clinical presentations of intracranial hypertension with or without focal neurological deficits. © 2005 Elsevier Ireland Ltd. All rights reserved. Keywords: Dural sinus stenosis; Dural sinus hypertension; Leptomeningeal angioma
1. Introduction Leptomeningeal angiomatosis is a common feature of Sturge–Weber syndrome (SWS) [1]. Intracranial and dural sinus hypertensions are also common findings of sinus thrombosis [2]. However, dural sinus hypertension due to segmental stenosis resulting in marked venous drainage via the diploic veins and leptomeningeal angiomatosis is unusual. Therefore, this rare case is described as a possible differential diagnosis of sinus thrombosis. Pertinent literature is reviewed as well.
2. Case report A 44-year-old male had persistent and intractable headaches over the right parieto-temporal area for 2 months. The headaches were characterized as dullness and fullness, accompanied by numbness and a crawling sensation over the right parieto-temporal scalp. Transient hemiparesthesia and ∗ Corresponding author. Tel.: +886 3 3281200x8418; fax: +886 3 3287226. E-mail address: [email protected] (Y.-J. Chang).
1571-4675/$ – see front matter © 2005 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.12.005
hemiparesis, ascending from the left leg to the left arm and even the left ear, or blurred vision with difficulty in measuring distance over the left visual field would occur sometimes when the headache was aggravated. Family history was unremarkable. Physical examinations were normal except for bilateral peripheral constriction of the visual field. Intracranial pressure measured by the lumbar puncture was slightly higher (200 mm CSF) and the analysis of CSF was also normal. Laboratory examinations were within normal levels, except for mild elevation of homocysteine (14.2, normal <12 mol/L). Brain computed tomography (CT) scan revealed enhanced hyperdense gyriform lesions in bilateral high parafalcine regions, especially over the right parietal area (Fig. 1A). Partial leptomeningeal enhancement over the cortex and falx was discovered (Fig. 1B). These gyriform lesions on subsequent brain magnetic resonance (MR) imaging were hypointense on the T1-weighted image (WI) and hyperintense on T2WI. Additionally, many hypointense lesions were scattered in the diploic space, pointing to engorged diploic veins (Fig. 2A). Gadolinium-enhanced T1WI and fluid-attenuated inversion recovery images revealed hyperintense imaging along the sulci over the gyri, suggesting leptomeningeal angiomatosis (Fig. 2B and C). The posterior third of superior sagittal sinus (SSS) was irregular, patent and
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K.-L. Huang et al. / European Journal of Radiology Extra 53 (2005) 91–93
Fig. 1. Hyperdense gyriform lesions (arrow) in the parasagittal area of the right hemisphere were revealed on non-contrast brain CT (A). Leptomeningeal enhancement (arrow head) was observed after contrast injection (B).
small caliber both on MR venography (Fig. 3A) and digital subtraction angiography (DSA); sinus thrombosis was suspected. The main venous outflow from the anterior two thirds of the SSS was drained unusually via the engorged sluggish diploic veins, and relative paucity of superficial cortical veins was detected over the territory of the posterior third of the SSS (Fig. 3B). Retrograde venography revealed abnormal pressure gradient between the anterior two thirds of the SSS (24 mmHg) and the right transverse sinus (11 mmHg). The CT venography disclosed segmental stenosis without thrombus in the posterior third of SSS (Fig. 4). The severity and frequency of the headache was markedly reduced by anticoagulant therapy. One episode of severe headache recurred because of the patient himself discontinuing medication. The headache was also relieved immediately and transiently for 3 days after angioplasty with balloon dilatation of the segmental stenosis via the right internal jugular vein. Unfortunately, the patient expired 2 weeks later due to massive intracranial hemorrhage after a traffic accident while under warfarin treatment.
3. Discussion The patient displayed persistent headaches and focal neurological signs of hemiparesis and hemiparesthesia. Laboratory examinations indicated no relevant findings, except for the unique radiological images. The diagnosis of sinus
Fig. 3. The SSS was patent on the MR venography, but the posterior third of SSS was irregular in caliber (arrow head) (A). Diploic veins (arrow) were clearly demonstrated in late venous phase on the digital subtraction angiography (B).
Fig. 4. The CT venography revealed patency in the posterior SSS (A). The caliber of the posterior SSS on the source images of CT venography was extremely small. No thrombus formation was disclosed (B).
thrombosis in the SSS is supported by the clinical presentations, pressure gradient measured by the retrograde venography, some brain and vascular images, and response to anticoagulant therapy. However, direct signs of thrombus were undetected and CT venography confirmed segmental stenosis without thrombus formation in the posterior SSS. Possible leptomeningeal angiomatosis and prominent drainage of diploic veins indicated possible congenital and chronic conditions. Therefore, the related etiologies must be clarified. SWS is characterized by a facial cutaneous angioma and an associated leptomeningeal and brain angioma, typically ipsilateral to the facial lesion, though Roach et al. did not consider the presence of a facial nevus as essential for diag-
Fig. 2. Many scattered hypointense lesions in the diploic space on T1WI meant abnormally engorged diploic veins (long arrow) as the prominent venous collateral system (A). The sulci over the right parietal lobe were partially enhanced by gadolinium (short arrow) on T1WI (B). These sulci presented hyper-intensity (arrow head) on FLAIR image, suggesting local fluid stasis (C).
K.-L. Huang et al. / European Journal of Radiology Extra 53 (2005) 91–93
nosing SWS [3]. Mental retardation, contralateral hemiparesis and hemiatrophy, and homonymous hemianopia are also common findings [1]. Leptomeningeal angioma is a typical feature of SWS. In this patient, although leptomeningeal enhancement and contralateral neurological signs persisted, no associated facial angioma was found. In addition, significant segmental narrowing occurred in the superior sagittal sinus and relative paucity of superficial cortical veins and prominent diploic veins were recognized on MR imaging and DSA. The diagnosis of SWS could not satisfactorily explain all of the patient’s features, despite that one hypotheses suggested that SWS could be owing to early venous thrombosis [1]. A confirmed diagnosis of cerebral venous thrombosis relies on demonstration of the thrombus by neuroimaging [4]. Non-invasive imaging by MR venography is preferred to cerebral angiography for the diagnosis and follow-up of cerebral venous thrombosis, although CT contrast venography remains popular in some centers and may constitute a superior technique in certain cases [5]. Some typical findings on CT scanning may point to newly formed cerebral venous thrombosis. The “empty delta sign”, noted by Buonanno et al. [6], on contrast CT scanning was the most frequent direct sign, in approximately 30% of published cases [2]. Other direct signs such as dense triangle sign and cord sign are relatively rare. In addition to its capacity to visualize the thrombus itself, MR imaging also demonstrates the evolution of thrombosis. In this case, no direct signs of thrombus were found on CT scanning and no typical evolution change of thrombus was found on the serial MR follow-up either, suggesting no evidence of newly formed thrombus. The image studies as mentioned above were insufficient to determine whether stenosis of the SSS was the result of recanalization of old thrombus. Kalbag et al. [7] found that the cerebral venous sinus in long survivors after thrombosis was filled with fibrous tissue, indicating that the clots in the sinus tended to become organized or absorbed. In this case, the caliber of the posterior SSS was about 3 mm, far smaller than the anterior part of the SSS. In such a small caliber, distinguishing the intraluminal obstruction from flow-related artifacts and hypoplasia on MR venography was extremely difficult. However, mere segmental narrowing without intraluminal filling defect was clearly evident in the source image
93
of CT venography. Ozsvath et al. reported that CT venography had competent sensitivity and specificity in diagnosis of dural sinus thrombosis, as compared with MR venography [5]. CT venography also had more credibility in the diagnosis of sinus occlusion because it revealed a filling defect within the involved sinus, gained more friendly source images and had less time consumption than the MR venography [5]. The presence of prominent diploic veins as the collateral drainage system implied that the stripe-like narrowing of the SSS could be a chronic change [8]. However, whether the segmental stenosis of the SSS was congenital or a long-term acquired problem remains unclear. In conclusion, dural sinus hypertension due to segmental stenosis, associated with leptomeningeal angiomatosis and dominant drainage from the diploic veins, is rarely discussed in the literature. Etiology and natural history still remain unknown. To differentiate dural sinus stenosis from the sinus thrombosis, the CT venography appears a better tool than the other vascular imaging studies, including DSA and MR venography, for such a case. The dural sinus stenosis should be a differential diagnosis, while patients have clinical presentations of intracranial hypertension with or without focal neurological deficits. References [1] Griffiths PD. Sturge–Weber syndrome revisited: the role of neurology. Neuropediatrics 1996;27:284–94. [2] Ameri A, Bousser MG. Cerebral venous thrombosis. Neurol Clin 1992;10:87–111. [3] Roach ES. Diagnosis and management of neurocutaneous syndromes. Semin Neurol 1988:83–96. [4] Kimber J. Cerebral venous sinus thrombosis. Q J Med 2002;95:137–42. [5] Ozsvath RR, Casey SO, Lustrin ES, et al. Cerebral venography: comparison of CT and MR projection venography. Am J Radiol 1997;169:1699–707. [6] Buonanno F, Moody DM, Ball MR, et al. Computed cranial tomographic findings in cerebral sino-venous occlusion. J Comput Assist Tomogr 1978;2:281–90. [7] Kalbag RM. Cerebral venous thrombosis. In: The cerebral venous system and its disorder. Orlando: Grune and Stratton; 1984. p. 505–35. [8] Paller AS. Vascular disorders. Dermatol Clin 1987;5:239–50.
Dural sinus hypertension due to segmental stenosis Kuo-Lun Huanga , Yeu-Jhy Changa,∗ , Chi-Jen Chenb b
a Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University, 199, Tung Hwa North Road, Taipei, Taiwan Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Chang Gung University, 199, Tung Hwa North Road, Taipei, Taiwan
Received 6 August 2004; received in revised form 20 December 2004; accepted 23 December 2004
Abstract We report a rare case with dural sinus hypertension due to segmental stenosis, associated with leptomeningeal angiomatosis and drainage from the diploic veins. The etiology and natural history still remain unknown. To differentiate dural sinus stenosis from the sinus thrombosis, the computed tomography venography appears to be a better tool than the other vascular imaging studies including the digital subtraction angiography in such a case. Dural sinus stenosis should be a differential diagnosis for patients with clinical presentations of intracranial hypertension with or without focal neurological deficits. © 2005 Elsevier Ireland Ltd. All rights reserved. Keywords: Dural sinus stenosis; Dural sinus hypertension; Leptomeningeal angioma
1. Introduction Leptomeningeal angiomatosis is a common feature of Sturge–Weber syndrome (SWS) [1]. Intracranial and dural sinus hypertensions are also common findings of sinus thrombosis [2]. However, dural sinus hypertension due to segmental stenosis resulting in marked venous drainage via the diploic veins and leptomeningeal angiomatosis is unusual. Therefore, this rare case is described as a possible differential diagnosis of sinus thrombosis. Pertinent literature is reviewed as well.
2. Case report A 44-year-old male had persistent and intractable headaches over the right parieto-temporal area for 2 months. The headaches were characterized as dullness and fullness, accompanied by numbness and a crawling sensation over the right parieto-temporal scalp. Transient hemiparesthesia and ∗ Corresponding author. Tel.: +886 3 3281200x8418; fax: +886 3 3287226. E-mail address: [email protected] (Y.-J. Chang).
1571-4675/$ – see front matter © 2005 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrex.2004.12.005
hemiparesis, ascending from the left leg to the left arm and even the left ear, or blurred vision with difficulty in measuring distance over the left visual field would occur sometimes when the headache was aggravated. Family history was unremarkable. Physical examinations were normal except for bilateral peripheral constriction of the visual field. Intracranial pressure measured by the lumbar puncture was slightly higher (200 mm CSF) and the analysis of CSF was also normal. Laboratory examinations were within normal levels, except for mild elevation of homocysteine (14.2, normal <12 mol/L). Brain computed tomography (CT) scan revealed enhanced hyperdense gyriform lesions in bilateral high parafalcine regions, especially over the right parietal area (Fig. 1A). Partial leptomeningeal enhancement over the cortex and falx was discovered (Fig. 1B). These gyriform lesions on subsequent brain magnetic resonance (MR) imaging were hypointense on the T1-weighted image (WI) and hyperintense on T2WI. Additionally, many hypointense lesions were scattered in the diploic space, pointing to engorged diploic veins (Fig. 2A). Gadolinium-enhanced T1WI and fluid-attenuated inversion recovery images revealed hyperintense imaging along the sulci over the gyri, suggesting leptomeningeal angiomatosis (Fig. 2B and C). The posterior third of superior sagittal sinus (SSS) was irregular, patent and
92
K.-L. Huang et al. / European Journal of Radiology Extra 53 (2005) 91–93
Fig. 1. Hyperdense gyriform lesions (arrow) in the parasagittal area of the right hemisphere were revealed on non-contrast brain CT (A). Leptomeningeal enhancement (arrow head) was observed after contrast injection (B).
small caliber both on MR venography (Fig. 3A) and digital subtraction angiography (DSA); sinus thrombosis was suspected. The main venous outflow from the anterior two thirds of the SSS was drained unusually via the engorged sluggish diploic veins, and relative paucity of superficial cortical veins was detected over the territory of the posterior third of the SSS (Fig. 3B). Retrograde venography revealed abnormal pressure gradient between the anterior two thirds of the SSS (24 mmHg) and the right transverse sinus (11 mmHg). The CT venography disclosed segmental stenosis without thrombus in the posterior third of SSS (Fig. 4). The severity and frequency of the headache was markedly reduced by anticoagulant therapy. One episode of severe headache recurred because of the patient himself discontinuing medication. The headache was also relieved immediately and transiently for 3 days after angioplasty with balloon dilatation of the segmental stenosis via the right internal jugular vein. Unfortunately, the patient expired 2 weeks later due to massive intracranial hemorrhage after a traffic accident while under warfarin treatment.
3. Discussion The patient displayed persistent headaches and focal neurological signs of hemiparesis and hemiparesthesia. Laboratory examinations indicated no relevant findings, except for the unique radiological images. The diagnosis of sinus
Fig. 3. The SSS was patent on the MR venography, but the posterior third of SSS was irregular in caliber (arrow head) (A). Diploic veins (arrow) were clearly demonstrated in late venous phase on the digital subtraction angiography (B).
Fig. 4. The CT venography revealed patency in the posterior SSS (A). The caliber of the posterior SSS on the source images of CT venography was extremely small. No thrombus formation was disclosed (B).
thrombosis in the SSS is supported by the clinical presentations, pressure gradient measured by the retrograde venography, some brain and vascular images, and response to anticoagulant therapy. However, direct signs of thrombus were undetected and CT venography confirmed segmental stenosis without thrombus formation in the posterior SSS. Possible leptomeningeal angiomatosis and prominent drainage of diploic veins indicated possible congenital and chronic conditions. Therefore, the related etiologies must be clarified. SWS is characterized by a facial cutaneous angioma and an associated leptomeningeal and brain angioma, typically ipsilateral to the facial lesion, though Roach et al. did not consider the presence of a facial nevus as essential for diag-
Fig. 2. Many scattered hypointense lesions in the diploic space on T1WI meant abnormally engorged diploic veins (long arrow) as the prominent venous collateral system (A). The sulci over the right parietal lobe were partially enhanced by gadolinium (short arrow) on T1WI (B). These sulci presented hyper-intensity (arrow head) on FLAIR image, suggesting local fluid stasis (C).
K.-L. Huang et al. / European Journal of Radiology Extra 53 (2005) 91–93
nosing SWS [3]. Mental retardation, contralateral hemiparesis and hemiatrophy, and homonymous hemianopia are also common findings [1]. Leptomeningeal angioma is a typical feature of SWS. In this patient, although leptomeningeal enhancement and contralateral neurological signs persisted, no associated facial angioma was found. In addition, significant segmental narrowing occurred in the superior sagittal sinus and relative paucity of superficial cortical veins and prominent diploic veins were recognized on MR imaging and DSA. The diagnosis of SWS could not satisfactorily explain all of the patient’s features, despite that one hypotheses suggested that SWS could be owing to early venous thrombosis [1]. A confirmed diagnosis of cerebral venous thrombosis relies on demonstration of the thrombus by neuroimaging [4]. Non-invasive imaging by MR venography is preferred to cerebral angiography for the diagnosis and follow-up of cerebral venous thrombosis, although CT contrast venography remains popular in some centers and may constitute a superior technique in certain cases [5]. Some typical findings on CT scanning may point to newly formed cerebral venous thrombosis. The “empty delta sign”, noted by Buonanno et al. [6], on contrast CT scanning was the most frequent direct sign, in approximately 30% of published cases [2]. Other direct signs such as dense triangle sign and cord sign are relatively rare. In addition to its capacity to visualize the thrombus itself, MR imaging also demonstrates the evolution of thrombosis. In this case, no direct signs of thrombus were found on CT scanning and no typical evolution change of thrombus was found on the serial MR follow-up either, suggesting no evidence of newly formed thrombus. The image studies as mentioned above were insufficient to determine whether stenosis of the SSS was the result of recanalization of old thrombus. Kalbag et al. [7] found that the cerebral venous sinus in long survivors after thrombosis was filled with fibrous tissue, indicating that the clots in the sinus tended to become organized or absorbed. In this case, the caliber of the posterior SSS was about 3 mm, far smaller than the anterior part of the SSS. In such a small caliber, distinguishing the intraluminal obstruction from flow-related artifacts and hypoplasia on MR venography was extremely difficult. However, mere segmental narrowing without intraluminal filling defect was clearly evident in the source image
93
of CT venography. Ozsvath et al. reported that CT venography had competent sensitivity and specificity in diagnosis of dural sinus thrombosis, as compared with MR venography [5]. CT venography also had more credibility in the diagnosis of sinus occlusion because it revealed a filling defect within the involved sinus, gained more friendly source images and had less time consumption than the MR venography [5]. The presence of prominent diploic veins as the collateral drainage system implied that the stripe-like narrowing of the SSS could be a chronic change [8]. However, whether the segmental stenosis of the SSS was congenital or a long-term acquired problem remains unclear. In conclusion, dural sinus hypertension due to segmental stenosis, associated with leptomeningeal angiomatosis and dominant drainage from the diploic veins, is rarely discussed in the literature. Etiology and natural history still remain unknown. To differentiate dural sinus stenosis from the sinus thrombosis, the CT venography appears a better tool than the other vascular imaging studies, including DSA and MR venography, for such a case. The dural sinus stenosis should be a differential diagnosis, while patients have clinical presentations of intracranial hypertension with or without focal neurological deficits. References [1] Griffiths PD. Sturge–Weber syndrome revisited: the role of neurology. Neuropediatrics 1996;27:284–94. [2] Ameri A, Bousser MG. Cerebral venous thrombosis. Neurol Clin 1992;10:87–111. [3] Roach ES. Diagnosis and management of neurocutaneous syndromes. Semin Neurol 1988:83–96. [4] Kimber J. Cerebral venous sinus thrombosis. Q J Med 2002;95:137–42. [5] Ozsvath RR, Casey SO, Lustrin ES, et al. Cerebral venography: comparison of CT and MR projection venography. Am J Radiol 1997;169:1699–707. [6] Buonanno F, Moody DM, Ball MR, et al. Computed cranial tomographic findings in cerebral sino-venous occlusion. J Comput Assist Tomogr 1978;2:281–90. [7] Kalbag RM. Cerebral venous thrombosis. In: The cerebral venous system and its disorder. Orlando: Grune and Stratton; 1984. p. 505–35. [8] Paller AS. Vascular disorders. Dermatol Clin 1987;5:239–50.