Venous drainage in multiple sclerosis: a combined MRI and ultrasound study.

BACKGROUND: Chronic cerebrospinal venous insufficiency (CCSVI) was proposed as the causal trigger for developing multiple sclerosis (MS). However, current data are contradictory and a gold standard for venous flow assessment is missing. OBJECTIVE: To compare structural magnetic resonance venography (MRV) and dynamic extracranial color-coded duplex sonography (ECCS) in a cohort of patients with MS. METHODS: We enrolled 40 patients (44 ± 10 years). All underwent contrast-enhanced MRV for assessment of internal jugular vein (IJV) and azygos vein (AV) narrowing, graded into 3 groups: 0%-50%, 51%-80%, and >80%. ECCS analysis of blood flow direction, cross-sectional area (CSA), and blood volume flow (BVF) in both IJV and vertebral veins (VV) occurred in the supine and upright body position. RESULTS: MRV identified 1 AV narrowing. IJV analysis yielded 12 patients for group 1 (30%), 19 patients for group 2 (48%), and 9 patients for group 3 (22%). By ECCS criteria, 4 patients (10%) presented with venous drainage abnormalities. Jugular BVF was different only between groups 1 and 3 (616 ± 133 vs. 381 ± 213 mL/min, p = 0.02). No other parameters in supine position and none of the parameters in the upright body position, apart from the IJV-BVF decrease in groups 1 and 3 (479 ± 172 vs. 231 ± 144 mL/min, p = 0.01), were different. CONCLUSIONS: Our ECCS data contradict the postulated 100% prevalence of CCSVI criteria in MS. MRV seems more sensitive to detect IJV narrowing compared to ECCS. A measurable hemodynamic effect only exists in vessel narrowings >80%. Our combined data argue against a causal relationship of venous narrowing and MS, favoring the rejection of the CCSVI hypothesis.

Transcranial color-coded sonography successfully visualizes all intracranial parts of the internal carotid artery using the combined transtemporal axial and coronal approach.

BACKGROUND AND PURPOSE: Visualization of the intracranial internal carotid artery (ICA) with transcranial color-coded sonography (TCCS) by using the transtemporal coronal plane has been described previously. Because this approach is limited to the vertical running ICA segments, we investigated the feasibility of using TCCS to visualize all intracranial ICA segments by adding the transtemporal axial approach to the coronal plane. MATERIALS AND METHODS: Subjects with excellent transtemporal acoustic windows were examined by TCCS by using standardized axial and coronal planes. Identification rate, flow velocities, pulsatility and resistance indices, and length (as visible in color-coded power mode) were determined. RESULTS: A total of 120 intracranial ICAs from 60 subjects were investigated. By switching between the axial and coronal insonation planes, all intracranial segments of the ICA could be investigated in 100% of subjects-with the exception of the horizontal part of the petrosal ICA, which was identified in 96.7% of subjects. CONCLUSIONS: TCCS becomes a reliable tool in investigating all parts of the intracranial ICA by adding the transtemporal axial approach to the coronal plane.

Incompetence of internal jugular valve in patients with primary exertional headache: a risk factor?

The pathophysiology of primary exertional headache (EH) is unknown. Physical exertion is associated with Valsalva-like manoeuvres (VM). VM leads to increased intrathoracic pressure and reduces cerebral venous drainage. Internal jugular vein valve incompetence (IJVVI) leads to retrograde venous flow during VM with transient increase of intracranial pressure. We analysed the prevalence of IJVVI in EH patients using duplex ultrasound. Bilateral measurements were performed at rest and during VM in 20 patients and 40 controls. Incompetence was concluded if retrograde venous flow could be seen in the jugular Doppler spectrum during repeated VM. Seventy percent of EH patients and 20% of controls demonstrated IJVVI, yielding a significant difference (P = 0.0004). IJVVI was always observed on the dominant venous drainage side. Our study suggests that intracranial venous congestion caused by retrograde jugular venous flow might play a role in the pathophysiology of EH with IJVVI as a risk factor.

Migraine and delayed ischaemic neurological deficit after subarachnoid haemorrhage in women: a case-control study.

The aim of the present case-control study was to investigate the role of migraine as a potential risk factor for a delayed ischaemic neurological deficit (DIND) after subarachnoid haemorrhage (SAH). A telephone interview was performed in patients or their relatives to determine the prevalence of migraine. Thirty-six women aged <60 years had SAH with Hunt & Hess grade I-III and DIND (group A). This group was compared with an age-matched group of 36 female SAH patients, Hunt & Hess grade I-III without DIND (group B). The two populations were also characterized regarding hypertension, smoking, diabetes mellitus and alcohol use. A significant difference was only found for the prevalence of migraine with 47% in group A and 25% in group B (P < 0.05; odds ratio: 2.68, confidence interval: 0.99-7.29). Migraineurs revealed similar prevalences of risk factors independently of the presence of DINDs. This retrospective study suggests that women with migraine have a higher risk to develop a DIND than women without migraine.

Multiple sclerosis coinciding with Machado-Joseph disease.

Although inflammatory demyelination is considered to be the key feature in multiple sclerosis (MS) pathogenesis, histopathological investigations and MRI studies recently highlighted the extent of neuronal damage that occurs even in the early stages of the disease. We report the unusual case of a patient with Machado-Joseph disease (MJD; spinocerebellar ataxia (SCA) III) and discuss this coincidence in light current pathogenetic paradigms of CNS autoimmunity.

Internal jugular vein valve incompetence and intracranial venous anatomy in transient global amnesia.

BACKGROUND: Recently a causal relation between internal jugular vein valve incompetence (IJVVI) and transient global amnesia (TGA) has been suggested. IJVVI is postulated to provoke a transient mesiotemporal ischaemia by venous congestion. This mechanism requires a patent venous pathway from the affected IJV through the transverse sinus, confluens, straight sinus (SS), vein of Galen into the basal vein of Rosenthal and the internal cerebral veins. OBJECTIVE: To study IJVVI in TGA patients in relation to the intracranial venous anatomy. METHODS: IJVVI was defined if a repeated Valsalva manoeuvre (VM) led to a retrograde jugular flow detected by extracranial duplex ultrasound. Non-contrast venous MR angiography (MRA) was performed to analyse intracranial drainage patterns of the SS in relation to the side of the IJVVI. SS drainage was differentiated into three groups: predominantly right, left, and bilateral drainage. Ultrasound studies were performed in 25 TGA patients and 85 age matched controls. Twenty patients underwent venous MRA. RESULTS: Sixty eight per cent of patients and 33% of controls showed unilateral or bilateral IJVVI (p = 0.0025). In 36% of patients a TGA preceding VM was reported. Drainage pattern of SS and side of IJVVI corresponded in five of eight patients (63%) with VM and four of 12 patients without VM (33%, p = 0.0994). CONCLUSION: Our study confirms the significantly higher prevalence of IJVVI in TGA patients. However, no specific IJVVI related intracranial venous drainage patterns could be found to further support the hypothesis of a direct causal relation between IJVVI and TGA.

A negative personal and family history for venous thrombotic events is not sufficient to exclude thrombophilia in patients with cerebral venous thrombosis.

A hereditary thrombophilia is found in 20-30% of patients with cerebral venous thrombosis (CVT). These patients might have an increased rate of a positive personal or family history of venous thrombotic events. We investigated the diagnostic value of a structured personal and family history for venous thrombotic events in 56 consecutive cases of CVT. Fourteen of 56 patients (25%) had a hereditary thrombophilia, mostly factor V Leiden. Patients with both CVT and hereditary thrombophilia had more frequently a positive family and personal history than patients affected by CVT only but the difference was not strong enough to differ from the 42 CVT patients without thrombophilia (43% vs. 31%; P = 0.52 and 14% vs. 10 %; P = 0.63). We conclude that a negative personal and family history of venous thrombotic events is not sufficient to exclude thrombophilia and patients with CVT should be tested for inherited thrombophilia regardless of the patient's past personal and family history for venous thrombotic events.

Heparin treatment in cerebral sinus and venous thrombosis: patients at risk of fatal outcome.

We performed a retrospective analysis of 79 patients with cerebral sinus venous thrombosis, who were treated with a fixed regimen of dose-adjusted intravenous heparin, to determine predictors of a fatal course. The parameters investigated were the state of consciousness and the presence of intracranial haemorrhage (ICH) at the start of heparin treatment, involvement of the internal venous system, mean delay from initial symptom to stupor or coma and from initial symptom to hospital admission, focal neurological deficits, mean intracranial circulation time (ICT) on conventional angiography, and age and sex distribution. Mortality rate was 10% in this series (8/79). There was a strong link between the outcome and the level of vigilance: 53% of the patients with stupor or coma at the start of the heparin therapy died (8/15), whereas all of the 64 patients with no more than mildly impaired vigilance survived (p < 0.00001). Furthermore, mean age and mean ICT were significantly higher in the group of patients who died. There was a statistical trend (p = 0.056) for ICH to be more frequent in cases with fatal outcome, but there was reason to assume that ICH represented an epiphenomenon of a severe course rather than an independent predictor. Other investigated parameters were not linked with a fatal outcome.

Transcranial ultrasonography of cerebral veins and sinuses.

Transcranial ultrasonography has become a valuable diagnostic tool for the bed-side evaluation of cerebral hemodynamics. While the assessment of arterial blood flow is well established, analysis of venous hemodynamics by transcranial ultrasonography is a new application of the method. The present review summarises the current state of transcranial venous ultrasound in adults by means of transcranial Doppler (TCD) and transcranial colour-coded duplex sonography (TCCS). It gives a critical overview regarding current and possible future clinical applications of the techniques.

Effects of prolonged head-down tilt on internal jugular vein cross-sectional area.

BACKGROUND: Head-down tilt is often used to assist cannulation of the internal jugular vein (IJV). However, the optimal duration of tilt before cannulation is not well defined. METHODS: Fifteen healthy volunteers were studied by B-mode duplex sonography to assess changes in cross-sectional area (CSA) of the right IJV during 10 degrees head-down tilt. RESULTS: Median CSA in the supine position was 102 mm(2) [range 16-266, mean (SD) 113 (69)]. CSA increased to 139 mm(2) [23-388, 158 (93)] immediately after tilting (P<0.0001, repeated measures ANOVA). No significant further change was noted in the next 20 min. CSA returned to baseline level after return to the supine position. CONCLUSION: The 10 degrees head-down tilt manoeuvre in healthy volunteers causes an immediate, significant increase in CSA in the right IJV. A longer tilt did not cause further increase in jugular CSA.

Venous collateral blood flow assessed by Doppler ultrasound after unilateral radical neck dissection.

Removal of the internal jugular vein (IJV) in unilateral radical neck dissection (rND) necessitates redirection of cerebrovenous blood to collateral pathways. If adaptation is insufficient, neurologic sequelae develop that are due to impaired venous drainage and increased intracranial pressure. The authors studied venous hemodynamic effects of unilateral rND using Doppler and duplex ultrasound in 17 patients. Blood flow velocities (BFVs) were recorded from the distal IJV (dIJV) and the vertebral vein (VV) before and 9 to 88 days after surgery. A preoperative compression test of the dIJV was performed to identify the side of dominant drainage. The BFV increased in the contralateral dIJV after right-sided rND (n = 10) by 111% (range, 50% to 320%), and after left-sided rND (n = 7) by 34% (range, 5% to 105%). In the contralateral VV, a rise of BFV by 75% was found. Our results confirm the role of the contralateral dIJV as the predominant collateral pathway. The VVs serve as an important additional major outflow. Doppler ultrasound may help to identify patients at risk of insufficient cerebrovenous drainage after rND.

Assessment of blood flow velocity and diameter of the middle cerebral artery during the acetazolamide provocation test by use of transcranial Doppler sonography and MR imaging.

BACKGROUND AND PURPOSE: Our purpose was to show changes in the diameter of the M1 segment of the middle cerebral artery (MCA) by using high-resolution MR imaging in patients with chronic internal carotid artery occlusion after IV administered acetazolamide challenge. Changes in blood flow velocity of the basal cerebral arteries are thought to correlate with changes of cerebral blood flow. Changes in the diameter of the basal cerebral arteries, however, might influence the validity of transcranial Doppler measurements. METHODS: Eight patients with internal carotid artery occlusion who were undergoing acetazolamide testing for assessment of cerebrovascular vasomotor reactivity were included in the study. Blood flow velocities of both MCAs were measured with transcranial Doppler sonography before and 25 minutes after the administration of acetazolamide. Before and 15 minutes after the administration of medication, MR imaging was performed contralateral to the occlusion side. A T2-weighted turbo-gradient spin-echo sequence was chosen to show a cross section of the M1 segment in high resolution (pixels, 0.27 x 0.29 mm). Based on interpolated data, the smallest and greatest MCA diameters were determined. RESULTS: We did not find changes in the diameter of the MCA after acetazolamide provocation testing with high-resolution MR imaging in patients with occlusive extracranial carotid artery disease. CONCLUSION: The results of our study support the hypothesis that changes in MCA flow velocity measured by transcranial Doppler sonography reflect relative changes in cerebral blood flow after acetazolamide provocation testing.

Measurement of cerebral circulation time by contrast-enhanced Doppler sonography.

We present a new, non-invasive ultrasound method for the measurement of cerebral circulation time. After injection of a galactose-based echo-contrast agent (Levovist) into an antecubital vein, cerebral circulation time is measured as the interval between the beginning of a stable signal enhancement of at least 5 dB in the internal carotid artery and in the ipsilateral internal jugular vein. Both vessels are insonated simultaneously at the mandibular angle using a single 2-MHz range-gated transducer. For this study, 25 healthy volunteers ranging in age from 23 to 55 years (30.1 +/- 7.5 years; mean +/- SD) were examined. Cerebral circulation time was 5.6 +/- 1.7 s without significant side-to-side or sex-related differences. Measurement of circulation times offers a new possibility for the employment of echo-contrast agents in functional ultrasound.