Hypoplasia Of Transverse Sinus Research Articles

Optic disc vessel density changes after shunt surgery in idiopathic intracranial hypertension

AimTo detect the change in optic disc vessel density in patients with idiopathic intracranial hypertension (IIH) after shunt surgery. Patients and methodTwenty-one patients with IIH underwent shunt surgery. Patients were subjected to full ophthalmic and neurological examinations. Optic disc vessel density was measured using optical coherence tomography angiography (OCT-A) before and two months after surgery. ResultsThe age of patients ranged from 27 to 48 years old, with a mean of (34.85 ± 6.87). Visual acuity ranged between 0.2 and 0.9 by log Mar, with a mean of (0.64±o.20). The mean deviation (MD) of the perimeter ranged from -22.9 to 0 dB, with a mean of (-9.77 ± 7.23 dB). With respect to the grade of papilledema, 15 eyes (35.7%) were of grade II, 21 eyes (50.0%) were of grade III, and 6 eyes (14.3%) were grade IV.Intracranial pressure measured by lumbar puncture (LP) prior to surgery ranged from 30 to 40 cm, with a mean of 35.43 cm. Except for right transverse sinus hypoplasia in 6 patients (28.6%), MRV was normal. In 15 patients (71.4%), lumboperitoneal shunt was performed, while ventriculoperitoneal shunt was performed in 6 patients (28.6%).After surgery, the optical disc vessel density was decreased in all patients. This decrease was highly significant for the whole image, the inner disc, the peripapillary, superior, and inferior hemispheres. Moreover, this reduction affected both optic disc microvasculature (referred to as capillary vessel density) and macro vasculature (also known as all vessel density).There were positive correlations between the CSF opening pressures and the preoperative optic disc vessel density of the whole image and inside disc with a P-value (0.002, 0.009), respectively. In addition, there was a positive correlation between the opening CSF pressures and the reduction in whole image vessel density after surgery with a P-value of 0.000. ConclusionOptic disc vessel density decreased after shunt surgery in patients with IIH. Consequently, optic disc vessel density can be used as a biomarker for the reduction of CSF opening pressure.

Effect of transverse sinus variation on the clinical outcomes of atherosclerotic anterior circulation infarction.

BackgroundHypoplasia of the transverse sinus (TS) is a common anatomical variation. The aim of this study was to investigate the effects of TS variation (i.e., TS hypoplasia) and no variation (i.e., TS symmetry) and their subgroups on the clinical outcomes of patients with atherosclerotic anterior circulation cerebral infarction (CI).MethodsA total of 75 patients were included in the study and were divided into the no TS variation group and the TS variation group. The TS variation group was further divided into the following subgroups: the TS variation with ipsilateral CI group and the TS variation with contralateral CI group. We retrospectively analyzed the correlations of the endpoint events of patients with large atherosclerotic anterior circulation infarction and TS no variant, and subgroups of TS variants.ResultsWe found that the diameter of the ipsilateral IJV in patients with TS variants were significantly smaller than those without TS variants, which was statistically significant (P<0.05). The differences in primary endpoint events, secondary endpoint events, and responsible vessel stenosis were not statistically significant when comparing the TS variant and no TS variant groups, and the TS variant subgroup (P>0.05). We found statistically significant differences in the National Institute of Health stroke scale (NIHSS) and Modified Rankin Scale (mRS) scores after 90 days of CI between the total anterior circulation infarct (TACI) TS variant group, the ipsilateral CI TS variant group, and the partial anterior circulation infarct (PACI) TS hypoplasia group and the ipsilateral CI TS variant group (P<0.05). There was a statistically significant difference (P<0.05) between the TS variant group with TACI, the TS variant group with ipsilateral CI, and the TS no variant group and the TS variant with contralateral CI group when comparing patients’ mRS scores after 90 days of CI.ConclusionsThe diameter of the internal jugular vein (IJV) ipsilateral to the TS variant was significantly smaller than that of the TS no variant. Patients with TACI in the TS variant group and one of its subgroups (the TS variant with ipsilateral CI group) had more severe clinical symptoms and a worse prognosis than patients in the same group with PACI.

Dural Venous Sinus Variations in Idiopathic Subarachnoid Hemorrhage: A New Indicator of the Venous Origin with Diagnostic Usefulness?

Venous hypertension associated with a primitive basal vein of Rosenthal (BVR) has been noted as the most likely cause of idiopathic subarachnoid hemorrhage (iSAH). Other types of venous drainage variations have been scarcely studied but may further explain the cases not associated with a BVR anomaly. Our aim was to investigate if dural venous sinus (DVS) anomalies are related with iSAH. A total of 76 patients diagnosed with iSAH were identified from a prospectively maintained database and their angiographic findings compared with 76 patients diagnosed with aneurysmal subarachnoid hemorrhage. On top of the BVR variations, our data showed a higher prevalence of transverse sinus hypoplasia (47.4% vs. 28.9%; P= 0.019), superior petrosal sinus hypoplasia (32.9% vs. 13.2%; P= 0.003), and clival plexus hyperplasia (65.8% vs. 43.4%; P= 0.005) in patients with iSAH. Analyzing by total number of angiograms, the iSAH group showed also a higher prevalence of inferior petrosal sinus hyperplasia (36.2% vs. 25%; P= 0.003). Of the patients with iSAH without a primitive BVR, 84% harbored ≥1 perimesencephalic DVS variation and the overall number of venous drainage variations was significantly higher in patients with iSAH. In addition to the well-documented BVR anomalies, there seems to be a significant relationship of other DVS variations in patients with iSAH. Transverse sinus hypoplasia, superior petrosal sinus hypoplasia, inferior petrosal sinus hyperplasia, and clival plexus hyperplasia were significantly more frequent in patients with iSAH. The presence of ≥3 of those variations would increase the suspicion of a nonaneurysmatic subarachnoid hemorrhage and could help avoid a second angiogram.

Non-contrast magnetic resonance venography with Inhance 3D Velocity: diagnostic performance for intracranial venous thrombosis.

The aim of this study was to evaluate the diagnostic performance of Inhance 3D Velocity (I3DV) in intracranial venous thrombosis and investigate the possible impact of venous sinus hypoplasia/aplasia on false thrombosis diagnosis made with I3DV. This study included 540 patients. Contrast-enhanced magnetic resonance venography combined with conventional sequences was considered the gold standard test (GST), while I3DV was considered as diagnostic test. We accessed the diagnostic success of I3DV for intracranial venous thrombosis detection, thrombosed vessel identification, and total/partial thrombus distinction. The possible relationship between false-positive thrombus diagnosed by I3DV and venous sinus hypoplasia or aplasia diagnosed by GST was investigated. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of I3DV in the detection of intracranial venous thrombosis were 95.7%, 92.1%, 64.1%, 99.3%, and 92.6%, respectively. A significant association was observed between I3DV and GST in terms of thrombosis detection and total/partial thrombus distinction (p < 0.001). A significant relationship was observed between false-positive thrombosis diagnosis in I3DV and hypoplasia in the left transverse sinus (p < 0.001). Intracranial venous thrombosis may be diagnosed faster and more accurately than traditional phase contrast magnetic resonance angiography in I3DV. This technique can be used in situations where contrast medium application is contraindicated. As in other non-contrast magnetic resonance venography techniques, left transverse sinus hypoplasia can be diagnosed as a thrombosed vessel in I3DV.

Does measurement of the jugular foramen diameter on MRI help to differentiate transverse sinus thrombosis from unilateral transverse sinus hypoplasia?

The transverse sinus (TS) is a frequent location of cerebral venous thrombosis. However, unilateral TS hypoplasia is a frequent variation and radiological imaging pitfall in the diagnosis because it may mimic unilateral TS thrombosis. The purpose of this study is to find a cutoff value for bilateral jugular foramen (JF) diameter ratios on magnetic resonance imaging (MRI) for differentiating TS thrombosis from TS hypoplasia. We retrospectively reviewed magnetic resonance venography results for 174 patients with reduced unilateral TS caliber resulting from either unilateral thrombosis (80 patients) or unilateral hypoplasia (94 patients). We calculated the ratio by proportioning the diameter of the JF ipsilateral to the TS with caliber reduction to the diameter of the contralateral JF. The Mann-Whitney U test was used to compare the ratios between thrombosis and hypoplasia groups, and the cutoff value was calculated by receiver-operating characteristic curve analysis. The ratio of bilateral JF diameters was lower in patients with hypoplasia than those with thrombosis (P < .01). The cutoff value to determine the diagnosis of TS hypoplasia with maximum accuracy was 0.638, with a sensitivity of 91.3% and specificity of 64.9%. In equivocal cases, calculating the cutoff value by proportioning the diameter of JF ipsilateral to the TS with caliber reduction to the contralateral JF seems to be an efficient, quick, and straightforward method and valuable aid to differentiate TS thrombosis from TS hypoplasia.

Occipital petalia as a predictive imaging sign for transverse sinus dominance

ABSTRACTObjectives: Occipital petalia is an anatomic description where one of the occipital lobes protrudes towards the contralateral side. Transverse sinus (TS) asymmetry might cause diagnostic challenges with regards to thrombotic or compressive pathologies involving these sinuses. In this study, we investigated the association between occipital petalia and TS hypoplasia on MRI studies.Methods: In 264 subjects with no neurological complaints, occipital bending was determined on T1-weighted images based on the angulation of interhemispheric fissure between occipital lobes with respect to an imaginary midline. TS asymmetry was evaluated visually. Information on handedness and ocular dominance was also gathered from all participants.Results: Rightwards bending was observed in 72 subjects (27%), whereas leftwards bending was present in only 10 participants (4%). The presence or direction of bending was related neither to hand nor ocular dominance. In participants with rightwards bending, 72% had a larger TS on the right-side, while only a single subject had a left-sided predilection for venous drainage. In subjects with leftwards bending, 70% had a left-dominant TS drainage system and none had a larger TS on the right. Overall, the direction of bending was predictive of TS dominance on the ipsilateral side with a PPV of 72% (95%CI, 60–82%) for right and 70% (95%CI, 35–92%) for left.Discussion: The direction of bending, a relatively straightforward radiologic diagnosis, is closely linked to the side of TS hypoplasia, and thereby might provide physicians with an additional diagnostic clue regarding the interpretation of imaging findings related to TSs and their pathologies.

Sinovenous Abnormalities in Patients of Idiopathic Intracranial Hypertension

Idiopathic Intracranial Hypertension is a disease of unknown aetiology common in obese females and presents with headache, papilledema, raised CSF opening pressure, no abnormalities in CSF examination and no abnormality on CT scan or MRI of the Brain. Sinovenous abnormalities are commonly detected in patients of IIH by different neuroimaging techniques. But the exact role of these sinovenous abnormalities in the causation of the disease or whether they are an effect of the disease is not yet known. Nor has a ‘gold standard’ investigation been established yet for detection of the sinovenous abnormalities. This study was done to detect the presence of sinovenous abnormalities in IIH patients by performing a Magnetic Resonance Venography of the brain. All 33 patients of IIH who presented to Rajshahi Medical College Hospital during the study period from June 2009 to May 2010 were included in the study. There were 30 females and 3 males having a F:M ratio of 10:1. 91% of the patients were between 20 and 35 years of age and most of them were married housewives. 63.64% patients had history of use of oral contraceptives. Unusually 51.52% of the patients had a BMI less than 25 indicating that they were not even overweight (BMI 25 to 30). Only 6% of the patients had BMI &gt; 30 indicating that they were obese. Headache and papilloedema were present in all patients but visual difficulties were present only in 54.54% of the patients. Abnormalities in MRV of the brain were detected in 27.27% (9/33) of the patients and transverse sinus hypoplasia was the commonest finding (88.89% - 8/9 patients). There was no statistically significant difference in the findings of MRV abnormalities between the males and females or among the patients having BMI less or more than 25TAJ 2013; 26: 53-56

Association between Transverse Sinus Hypoplasia and Cerebral Venous Thrombosis: A Case-Control Study

Hypoplasia of the transverse sinus (TS) is a common anatomical variation. However, the relationship between TS hypoplasia and venous thrombosis has not been studied. We analyzed the hypothesis that TS hypoplasia is a predisposing factor for ipsilateral thrombosis. We retrospectively evaluated 20 confirmed cases with isolated TS thrombosis and 43 age- and sex-matched controls. TS thrombosis and hypoplasia were diagnosed using both computed tomography and magnetic resonance venography. Hypoplasia was defined as a TS diameter less than 50% of the cross-sectional diameter of the lumen of the distal superior sagittal sinus and by a bony groove ratio less than 1.02. Univariate analysis was performed to evaluate the association between TS hypoplasia and thrombosis. There were a total of 45 hypoplastic TS: 31 (49%) left hypoplastic TS (12 (60%) cases vs 19 (44%) controls (P = .24), and 14 (22%) right hypoplastic TS (9 (45%) cases vs 5 (12%) controls (P = .003). TS hypoplasia was more frequently found in cases (n = 18, 90.0%) than in controls (n = 22, 51.2%; relative risk 1.7, confidence interval [CI] 95% 1.3-2.4, P = .003). Hypoplastic TS and ipsilateral TS thrombosis showed a significant association (P = .002 for right and P = .008 for left TS hypoplasia) with relative risk of 3.8 (95% CI 1.3-10) for right and 7.5 (95% CI 1.1-48) for left hypoplasia. No significant association was found between hypoplastic TS and functional outcome at 30- or 90-day follow-up. TS hypoplasia might be a predisposing factor for ipsilateral TS thrombosis, but not for functional outcome.

Transverse Sinus Hypoplasia as a Predisposing Factor for Cerebral Venous Thrombosis (P1.245)

Transverse Sinus Hypoplasia as a Predisposing Factor for Cerebral Venous Thrombosis (P1.245)

Diagnosis of Transverse Sinus Hypoplasia in Magnetic Resonance Venography: New Insights Based on Magnetic Resonance Imaging in Combined Dataset of Venous Outflow Impairment Case-Control Studies: Post Hoc Case-Control Study.

In previous studies of transverse sinus (TS) hypoplasia, discrepancies between TS diameter measured by magnetic resonance venography (MRV) and contrast T1-weighted magnetic resonance (contrast T1) were observed. To investigate these discrepancies, and considering that TS hypoplasia is associated with neurological disorders, we performed a post hoc analysis of prospectively collected data from 3 case–control studies on transient global amnesia (TGA), transient monocular blindness (TMB), and panic disorders while retaining the original inclusion and exclusion criteria. Magnetic resonance (MR) imaging of 131 subjects was reviewed to evaluate TS diameter and the location and degree of venous flow stenosis and obstruction.MRV without contrast revealed that TS hypoplasia was observed in 69 subjects, whom we classified into 2 subgroups according to the concordance with contrast T1 observations: concordance indicated anatomically small TS (30 subjects), and discrepancy indicated that the MRV diagnosis is in fact flow-related and that TS is not anatomically small (39 subjects). The latter subgroup was associated with at least 1 site of venous compression/stenosis in the internal jugular vein (IJV) or the left brachiocephalic vein (BCV) (P < 0.001), which was significantly larger in patients than controls. Compensatory dilatation of contralateral TS diameter was only observed with MRV, not with contrast T1 imaging.The clinical implication of these results is that using MRV only, IJV/BCV compression/stenosis may be misdiagnosed as TS hypoplasia. And contralateral TS have no compensatory dilatation in its diameter in contrast T1 imaging, just compensatory increased flow volume.

Abstract WP224: Transverse Sinus Hypoplasia as a Predisposing Factor for Cerebral Venous Thrombosis

Background: Transverse sinuses (TS) are frequently asymmetric. Hypoplasia or aplasia of TS is a common anatomical variation, right TS is dominant in 61% of cases. The relationship between hypoplastic TS and cerebral venous thrombosis is not well established. Hypothesis: Transverse sinus hypoplasia is a predisposing factor for ipsilateral transverse sinus thrombosis Methods: We retrospectively evaluated 27 confirmed cases with isolated transverse sinus thrombosis and 54 age-and-sex matched controls, treated in a Neurological tertiary center from 2010 to 2015. A stroke neurologist and a neuroradiologist measured TS using an MRI sequence (Inhance 3D Inflow IR); interrater reliability was calculated using Bland-Altman plots. Hypoplasia was defined as a transverse sinus diameter less than 50% of the cross-sectional diameter of the lumen of the distal superior sagittal sinus. Univariate analysis was performed to evaluate the association between transverse sinus hypoplasia (TSh) and thrombosis. Results: There was a good inter-rater reliability (p=0.55 on the Bland-Altman plot by ANOVA test). There were a total of 45 left hypoplastic transverse sinuses (TS) (19 [70.4%] cases vs. 26 [48.1%] controls), and 16 right hypoplastic TS (11 [40.7%] cases vs. 5 [9.3%] controls). Ipsilateral thrombosis was present in 9 (33.3%) right and 15 (55.5%) left hypoplastic transverse sinuses. Transverse sinus thrombosis was more likely to be present when associated with left TSh (RR 2.57, 95% CI 1.17-5.69; p=0.001), than right TSh and ipsilateral thrombosis (RR 0.15, 95% CI 0.04-0.57; p&lt;0.001). Conclusion: Isolated transverse sinus hypoplasia might be a predisposing factor for ipsilateral transverse sinus thrombosis.

Obstruction of Venous Drainage Linked to Transient Global Amnesia.

Abnormal extracranial venous drainage modality has been considered an etiology of transient global amnesia (TGA). Evidence suggests that the transmission of the intrathoracic/intraabdominal pressure during a Valsalva maneuver (VM) is mainly through the vertebral venous system, and patency of internal jugular vein (IJV) is essential for venous drainage and pressure releasing. We hypothesize that obstruction of IJV venous drainage is a contributing factor in TGA pathogenesis. A magnetic resonance (MR) imaging protocol was used in 45 TGA patients and 45 age- and sex-matched controls to assess the morphologies of IJV, brachiocephalic vein (BCV) and asymmetry of transverse sinus (TS). The IJV was divided into the upper- and middle-IJV segments. Compared to the controls, TGA patients had significantly higher rates of moderate and severe compression/stenosis at the bilateral upper-IJV segment (left: 37.8% vs. 17.8%, P = 0.0393; right: 57.8% vs.15.6%, P<0.0012), in left BCV (60% vs. 8.9%, P<0.0004), and in TS hypoplasia (53.3%% vs. 31.1%, P = 0.0405). The prevalence of at least one site of venous compression/stenosis in IJV or BCV was significantly higher in patients than in controls (91.1% vs. 33.3%, P<0.0004). The diameter of the left TS in MRV, but not in T1 contrast imaging, was significantly smaller in TGA patients than in controls (0.31±0.21 vs. 0.41±0.19, P = 0.0290), which was compatible with downstream venous stenosis/obstruction. TGA patients have a higher prevalence of compression/stenosis of the bilateral IJV and the left BCV and TS hypoplasia, which is new evidence that supports the role of extracranial veins in TGA pathogenesis.

VARIATIONS IN MAGNETIC RESONANCE VENOGRAPHIC ANATOMY OF THE DORSAL DURAL VENOUS SINUS SYSTEM IN 51 DOGS

Variations in intracranial dural venous sinus anatomy have been widely reported in humans, but there have been no studies reporting this in dogs. The purpose of this retrospective study was to describe variations in magnetic resonance (MR) venographic anatomy of the dorsal dural venous sinus system in a sample population of dogs with structurally normal brains. Medical records were searched for dogs with complete phase contrast, intracranial MR venograms and a diagnosis of idiopathic epilepsy. Magnetic resonance venograms were retrieved for each dog and characteristics of the dorsal dural sinuses, symmetry of the transverse sinuses and other anatomic variations were recorded. A total of 51 dogs were included. Transverse sinus asymmetry was present in 58.8% of the dogs, with transverse sinus hypoplasia seen in 39.2%, and aplasia in 23.5% of dogs. For 70.6% of dogs, at least one anatomic variation in the dorsal sagittal sinus was observed, including deviation from the midline (33.3%) and collateral branches from either the dorsal sagittal sinus or dorsal cerebral veins (54.9%). In 5 dogs (9.8%) a vessel was also identified running from the proximal transverse sinus to the distal sigmoid sinus, in a similar location to the occipital sinus previously reported in children. Findings from this study indicated that, as in humans, anatomic variations are common in the intracranial dural venous sinus system of dogs. These anatomic variations should be taken into consideration for surgical planning or diagnosis of cerebrovascular disease.

Ipsilateral evaluation of the transverse sinus: Transcranial color-coded sonography approach in comparison with magnetic resonance venography

The ultrasound examination of intracranial venous structures by transcranial color-coded sonography (TCCS) is a validated and standardized application. Similarly some intracranial venous sinuses are known for their relatively low insonation rate, as straight sinus (SRS) and transverse sinus (TS), ranging from 35% to 73%. The relatively high frequency of hypoplasia of TS can partially take account for these data. The aim of this study is to evaluate the feasibility of this approach in a standard TCCS examination, in comparison with magnetic resonance (MR) findings by using the Virtual Navigator system. The standardized approach to the TS was a contralateral insonation, starting to the SRS plane and angulating downwards the probe. In this way it is possible to insonate the proximal segment of the contralateral TS. We proposed a new approach with an extreme downwards tilting and a slow opposite angulation of the probe for examining the ispilateral TS. Forty consecutive subjects were chosen among patients who underwent standard TCCS examinations at our lab and had a suitable temporal acoustic window, and a recently performed MR venography. The contralateral TS insonation rate was compared with the ipsilateral one. The insonation rate was 61/80 (76.25%) for the contralateral TS and 75/80 (93.75%) for the ipsilateral approach. Two of 5 not detectable TS were aplasic in MR venography and the others were not identified by a poor acoustic window. The ipsilateral approach could be associated to the contralateral standard study for insonating the TS.

Polycystic Kidney Disease Associated with Cervical Arteriovenous Shunt and Bilateral Jugular Vein Occlusion.

A 59-year-old man with abnormal vascular features (intracranial aneurysm, a cervical arteriovenous shunt, bilateral internal jugular vein occlusions, and left transverse sinus hypoplasia), as well as left optic atrophy was suspected to have familial polycystic kidney disease. The possibility of autosomal dominant polycystic kidney disease complicated by Ehlers-Danlos syndrome type IV due to the coexistence of vasculopathy and polycystic kidneys was considered. However, the negative results of a skin fibroblast culture rendered the diagnosis of Ehlers-Danlos syndrome type IV unlikely. The cause of left optic atrophy in our patient remains unclear although it was suspected to be a secondary consequence of papilledema, which was caused by intracranial hypertension.