Diagnosis Of Dural Sinus Thrombosis Research Articles

Dural sinus thrombosis: pre- and postnatal MRI observation

Highlights. The clinical case report describes the important role of MRI in the perinatal diagnosis of dural sinus thrombosis, timely verification of the diagnosis, differential diagnosis with other vascular and tumor formations of the brain.Abstract. Dural sinus thrombosis (DST) is a rare congenital anomaly. Ultrasound findings usually mimic intracranial tumors. As a result, the condition is often misdiagnosed and its frequency in general population is underestimated. According to literature data, the progression of DST is a favorable prognosis in case of absence of other concomitant pathologies of the fetal brain. We present a case of DST that was detected with ultrasound, and verified by numerous pre and postnatal MRI starting from 22 weeks of gestation till 4 years of life. A case with a favorable neurological outcome, postnatal ventriculosubgaleal shunting, and ventriculoperitoneal shunting was followed with MRI and CT before and after interventions. The aspects of differential diagnosis, factors determining prognosis are presented. The presented case demonstrates a significant role of fetal MRI in DST diagnosis, depiction of the internal structure of the expanded sinus, and exclusion of concomitant pathology of the brain. These MRI data are integral in determining the appropriate perinatal management, and can be used as predictors of the favorable neurological outcome despite of the severity and size of prenatally diagnosed DSТ.

Pearls and Pitfalls in the Magnetic Resonance Diagnosis of Dural Sinus Thrombosis: A Comprehensive Guide for the Trainee Radiologist.

Dural sinus thrombosis (DST) is a potentially fatal neurological condition that can be reversed with early diagnosis and prompt treatment. Non-enhanced CT scan is often the first imaging investigation in patients presenting with acute neurological symptoms; however, its poor sensitivity in detecting DST is a major drawback. Magnetic resonance (MR) imaging offers multiple advantages such as excellent contrast resolution and unenhanced venography possibilities, making it the mainstay in the non-invasive diagnosis of DST. However, physiological variations, evolution of thrombi, and incorrect selection/application of MR techniques can lead to false positive and false negative interpretations impacting patient management and outcome. This article discusses the MR techniques useful to diagnose DST and describes pitfalls, with troubleshooting methods, to ensure an accurate diagnosis. We have used multiple diagrammatic illustrations and MR images to highlight pertinent take-home points and to serve as an easy guide for day-to-day clinical practice.

Cerebral Venous Thrombosis: Diagnostic Accuracy of Combined, Dynamic and Static, Contrast-Enhanced 4D MR Venography

MR including MRV is an established method to diagnose CVT. However, it remains unsettled which MR imaging modalities offer the highest diagnostic accuracy. We evaluated the accuracy of a combined, dynamic (1.5 seconds per dataset) and static (voxel size, 1.1 x 0.9 x 1.5 mm), contrast-enhanced MRV method (combo-4D MRV) relative to other established MR/MRV modalities. A total of 39 patients with CVT (n = 20) and control subjects (n = 19) underwent combo-4D MRV, 2D TOF MRV, GRE imaging, and T2W imaging. For these modalities, diagnostic accuracy (ROCs) for CVT affecting 53 out of 234 predefined venous segments was determined. Sensitivity and specificity were separately calculated for different stages of CVT (acute/subacute/chronic). Combo-4D MRV showed the highest accuracy (AUC, 0.99 [95% CI, 0.97-1.0]; sensitivity, 97% [84%-100%]) for thrombosed dural sinuses. For all thrombosed segments including cortical veins, its sensitivity was best (76% [64%-84%]; AUC, 0.92 [0.88-0.96]), followed by TOF MRV (72% [59%-81%]; AUC, 0.93 [0.88-0.97]). Even for chronic CVT, it showed a relatively high sensitivity of 67% (30%-90%). For thrombosed cortical veins alone, GRE images achieved the highest sensitivity (66% [46%-81%]; AUC, 0.88 [0.78-0.97]). Specificities of all modalities ranged from 96% to 99%. Combo-4D MRV showed an excellent accuracy for the diagnosis of dural sinus thrombosis. The analysis of dynamic patterns of contrast enhancement in dural sinuses appeared useful to identify chronic thrombosis. To diagnose thrombosed cortical veins, GRE images should primarily be analyzed.

Imaging of the Intracranial Venous System

Evaluation of the intracranial venous system has historically been performed with conventional catheter-based digital subtraction angiography (DSA). The continued importance of DSA can not be overstated in light of its inherent option of endovascular intervention and thrombolysis for cerebral venous thrombosis. DSA is, however, an invasive procedure with associated risks, including radiation exposure, and adverse effects of iodinated contrast medium. DSA also suffers from the limitations of 2-dimensional planar imaging. For these reasons, noninvasive imaging techniques are playing a greater role in evaluation of the intracranial venous system. This review provides an overview of the current noninvasive methods and their applications and limitations, with examples of their use in a variety of disease processes. Computed tomography venography (CTV) is discussed as well as the various types of cerebral magnetic resonance venography (MRV). When available, MR supplemented with the technique of triggered gadolinium-enhanced MRV is the method of choice for the diagnosis of dural sinus thrombosis as well as most other pathologic entities affecting the intracranial venous system.

Otitic hydrocephalus associated with lateral sinus thrombosis and acute mastoiditis in children

The incidence of intracranial complications of acute otitis media (AOM) has decreased and the need for operative and medical treatment is declined during the antibiotic era. To describe pathognomonic signs, evaluation management, operative findings, clinical course and outcome of otitic hydrocephalus and lateral sinus thrombosis as complications of AOM and mastoiditis in pediatric patients. Two children, 9 and 13 years old, with the diagnosis of OH and TK and MRI findings are presented. Intracranial complications in children resulted from unsuccessful treatment of AOM, which led to acute mastoiditis and lateral sinus thrombosis. Both of the presented children had thrombus in their sigmoid sinus preoperatively, demonstrated by MRI, causing decreased blood flow. Both patients underwent a mastoidectomy and delamination of sigmoid sinus with puncture of sinuses. After medical and surgical treatment, blood flow through the sinus increased significantly. In both cases signs of increased intracranial pressure ceased. The clinical presentation of otogenic lateral sinus thrombosis (LST) as a complication of acute otitis media (AOM) can be masked by antibiotic treatment. The episodes of vomiting, headache, visual impairment and a history of AOM seem to be indicative for otitic hydrocephalus. MRI scans of patients with similar symptoms should be carefully studied to facilitate the early diagnosis of dural sinus thrombosis with increased intracranial pressure. Contrast-enhanced computed tomography scan and magnetic resonance imaging play a major role in determining diagnosis and treatment plans in this intracranial complications. Management included systemic antibiotics, short-term heparin anticoagulation and surgical decompression. In our patients intensive i.v. antibiotic treatment, steroids, anticoagulants and surgery led to a significant improvement in the clinical condition.

Report on the ECR2003 (European Congress of Radiology): non-contrast intracranial MR venography with 3D-phase contrast imaging: optimization of presaturation pulse and velocity encoding

Intracranial MR venography is useful for the diagnosis of dural sinus thrombosis and the preoperative assessment of sinus patency encased by tumors. Recently, contrast-enhanced MR venography has been applied for suspected dural sinus occlusion in a shorter time. However, it has some disadvantage for the evaluation of hypervascularized enhancing thrombus mimicking flow in chronic sinus thrombosis. So far, we have evaluated optimal imaging technique and slice orientation and have shown that sagittal three-dimensional (3D) -phase contrast (PC) imaging is the most suitable for the non-contrast intracranial MR venography. To assess the optimal presaturation pulse (SAT) and velocity encoding (VENC) for the non-contrast intracranial 3D-PC MR venography. Firstly, we performed phantom experiment to assess the best SAT thickness using arterial presaturation. Second, MR imaging was performed in 7 healthy volunteers to measure the dural sinus flow velocity using a 1.5 T MR. Third, 3D-PC MR venography was performed with a VENC settings at 10, 15, 20 and 30 cm/sec for healthy volunteers. All data were displayed as maximum intensity projection images and three neuroradiologists assessed the visibility of the dural sinuses and the cortical vein. The mean flow velocity of the dural sinuses was 6.3 cm/sec. The thickness of the best SAT was 100 mm. In the assessment of the visibility of the 3D-PC images, dural sinuses were adequately visualized at a VENC of 15 cm/sec. Non-contrast intracranial 3D-PC MR venography was optimized at 100mm thickness of SAT and a VENC of 15 cm/sec.

Hypointense thrombus on T2-weighted MR imaging: a potential pitfall in the diagnosis of dural sinus thrombosis

Purpose: To determine the frequency of hypointense appearance of dural sinus thrombosis on T2-weighted images, which may mimic a normal flow void, and when possible correlate with appearance on T1-weighted images. Methods and Materials: Retrospective review of radiology files showed 51 patients with a discharge diagnosis of dural sinus thrombosis who underwent MR imaging during the period 1986–1998. These images were reviewed by an experienced neuroradiologist for appearance on T2-weighted images. This process yielded five cases in which a hypointense appearance on this pulse sequence simulated a normal flow void. An additional two cases were added from the teaching files of two other institutions giving a total of seven cases (13% of studies). The resulting study population consisted of five women and two men (mean age 27.1 years). T1 weighted images were available in five patients. In two patients MR venography was available, but not T1-weighted images. The diagnosis of dural sinus thrombosis was based solely on absence of flow void on T1-weighted images in one case, solely on absence of flow void on MR venography in two cases and absence of flow void on T1-weighted images in conjunction with MR venography or gradient echo findings in 4 patients. All images were obtained on a 1.5 T magnet (GE Medical Systems; Milwaukee, Wisconsin). Results: In all patients hypointense signal of thrombus was isointense with normal flow voids in other dural sinuses on T2-weighted images. In all cases in which T1-weighted images were available, the signal intensity of thrombus was isointense to gray matter. Conclusion: Hypointense appearance of thrombus on T2-weighted images is a potential pitfall in the MR diagnosis of dural sinus thrombosis. Because thrombus in this stage of evolution appears isointense to gray matter on T1-weighted images, careful attention must be paid to other sequences to avoid this pitfall.

Cerebral CT venography.

To produce cerebral venograms with thin-section helical computed tomography (CT) and to assess their diagnostic utility. Thirty-six CT venograms were obtained in 33 patients after intravenous administration of iodinated contrast material. Eighteen patients had suspected dural sinus thrombosis. Twelve patients had tumor adjacent to a major venous structure. Three patients underwent CT venography during CT angiography. Superior sagittal, transverse, and straight sinuses were identified on every CT venogram. Other veins were seen with high frequency. Dural sinus thrombosis was diagnosed in seven patients, with magnetic resonance (MR) venographic correlation in five patients. CT venograms were easier to interpret and had fewer artifacts than MR venograms. Relationships of tumor to adjacent cerebral venous structures were well shown on CT venograms. CT venography yields detailed images of the intracranial venous circulation with consistently high quality. It is a rapid, useful method for diagnosis of dural sinus thrombosis and for preoperative mapping of venous structures in patients with neoplasm.

Dural sinus thrombosis: value of venous MR angiography for diagnosis and follow-up.

The purpose of this study was to determine the value of venous MR angiography as the sole procedure for the diagnosis and follow-up of dural sinus thrombosis. Forty-two patients with clinical findings suggestive of dural sinus thrombosis were examined with venous MR angiography and spin-echo MR imaging. Maximum-intensity-projection reconstructions and individual sections of the MR angiograms were examined for direct and indirect signs of dural sinus thrombosis by assessing flow signal from the major sinuses, the jugular bulb, upper jugular veins, ascending cortical veins (occlusion or increased flow due to formation of collaterals), diploe (emissary) veins and extracranial veins, and the deep subcortical veins (Galen's and internal cerebral veins). Direct signs of dural sinus thrombosis on MR angiograms included lack of typical high flow signal from a sinus that did not appear aplastic or hypoplastic on single sections from MR angiography and the frayed appearance of the flow signal from a sinus after recanalization. Indirect signs of dural sinus thrombosis included evidence of formation of collaterals, unusually prominent flow signal from deeper medullary veins, cerebral hemorrhage, visualization of emissary veins, and signs of increased intracranial pressure. When available, conventional angiograms were evaluated by analogous criteria as appropriate. Digital subtraction or cut-film angiograms were available for correlation in nine patients. In nine patients, MR angiography was repeated up to eight times during the course of follow-up. The results of MR angiography for all patients were compared with results in 10 control subjects. Confirmation of the diagnosis of dural sinus thrombosis was based either on conventional angiographic findings or on the changes seen in follow-up examinations. Dural sinus thrombosis could be ruled out in 25 of the 42 patients on the basis of clinical and MR angiographic findings. In 17 patients with MR angiographic findings that indicated dural sinus thrombosis, conventional angiography confirmed the diagnosis in nine patients, and changes seen on repeat MR angiograms during follow-up confirmed the diagnosis in nine patients as well (one patient's diagnosis was confirmed by both techniques). Individual frames from two-dimensional fast low-angle shot sequences allowed direct visualization of thrombus. Limited spin-echo sequences as performed here provided inconsistent findings and were insufficient for diagnosis. In the 10 control subjects, attenuation of flow signal was seen in the torcular Herophili in all studies; one subject had a nonpathologic variant of the sinojugular system. MR angiography is the technique of choice for diagnostic evaluation and follow-up of dural sinus thrombosis, and it is reliable as the sole examination for this condition. When MR angiographic findings are unremarkable and other abnormalities must be ruled out, routine spin-echo MR imaging should be performed.

Magnetic resonance imaging of thrombosed dural sinuses.

Magnetic resonance imaging should have the potential to replace angiography in the diagnosis of dural sinus thrombosis. Concerning time-dependent signal changes of the thrombus, we intended to develop a standardized examination protocol for routine use in suspected dural sinus thrombosis. The time-dependent signal changes of thrombosed dural sinuses were studied in 23 consecutive patients by multiplanar spin-echo and flow-sensitive sequences. Signal intensities and thrombus homogeneity were graded and related to the time after clinical onset and the results of the magnetic resonance angiography. Four stages of the thrombus evolution could be observed. The acute thrombosis (days 1 to 5) appeared strongly hypointense in T2-weighted images and isointense in spin density- and T1-weighted images. In the subacute stage (up to day 15) the thrombus signal was strongly hyperintense in T1- and T2-weighted images. The third stage began in the third week after clinical onset. The thrombus signal was decreased in all sequences and showed an increasing inhomogeneity. The fourth (late) stage was characterized by either the restitution of blood flow or the persistence of a residual thrombus. Each stage requires a different diagnostic approach. With the combined use of spin-echo and gradient-echo sequences, it is possible to make the diagnosis of acute thrombosis; in the second stage, multiplanar spin-echo sequences are sufficient. Diagnosis of dural sinus thrombosis can be established accurately with magnetic resonance imaging in the first two stages. However, the diagnosis of the later stages is difficult because of inhomogeneous signs of recanalization and flow phenomena. Therefore, a suspected older dural sinus thrombus still requires intra-arterial angiography as the primary diagnostic tool.

Papilloedema in Behcet's disease: value of MRI in diagnosis of dural sinus thrombosis.

Behçet's disease is a multisystem disease characterised by the clinical triad of oral ulcers, genital ulcers and uveitis. Nervous system involvement is frequent and occasionally precedes other manifestations. Behcet's disease is not frequently considered in the differential diagnosis of papilloedema. We report four cases of Behcet's disease in which papilloedema occurred with or without dural sinus thrombosis. MRI is of great value in the investigation of such patients as it can demonstrate venous sinus thrombosis non-invasively or suggest the diagnosis by showing the associated parenchymal lesions secondary to small vessel pathology.

Dural sinus thrombosis

Magnetic resonance imaging has been reported to have advantages over conventional angiography in the diagnosis of dural sinus thrombosis. A case report is presented describing the application of MR techniques including MR angiography, to diagnose and monitor therapy for dural sinus thrombosis.