Jugular venous reflux in cerebral radionuclide angiography: an explanation

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.

Suboptimal contrast opacification of dynamic head and neck MR angiography due to venous stasis and reflux: technical considerations for optimization

BACKGROUND AND PURPOSE

Contrast-enhanced head and neck MRA may be degraded by venous stasis and reflux of contrast into the jugular veins. The purpose of this study was to evaluate the relationship between venous stasis and reflux and the side of injection and other causal factors.

MATERIALS AND METHODS

One hundred twenty-six consecutive patients (94 males and 32 females) who underwent contrast-enhanced MRA were evaluated for the side of contrast injection (left, n = 65; right, n = 61), hypertension, and cardiac disease. The retrosternal space was measured in all patients with left-arm injections.

RESULTS

Eight patients (6.34%) had reflux into the jugular veins. The difference in the mean ages of patients with and without reflux was not significant (P = .069). There was a significant difference in the incidence of systemic hypertension in patients with (77.78%) and without reflux (23.73%; P = .007). There was no significant difference in the incidence of cardiac disease in patients with and without reflux (P = .323). The difference in the side of injection in patients with and without reflux (P = .005) and the difference in the mean retrosternal distance in the patients with left-arm injection with (7.2 mm) and without reflux (12.1 mm) were statistically significant (P < .001).

CONCLUSIONS

Compression of the left brachiocephalic vein between the sternum and a tortuous aorta and proximal vessels may lead to venous reflux that can degrade the quality of contrast-enhanced MRA. Our study suggests that venous reflux can be avoided by routinely injecting right-sided veins.

Pseudopathologic brain parenchymal enhancement due to venous reflux from left-sided injection and brachiocephalic vein narrowing

In this report, we present a case of a patient with CT angiographic artifacts related to left-sided venous injection resulting in a striking pattern of enhancement simulating vascular abnormalities, which prompted additional diagnostic imaging. To our knowledge, no similar case has been reported in the published literature to date.

Venous Reflux on Carotid Computed Tomography Angiography

OBJECTIVE

We evaluated the relationship between image degradation due to the reflux of contrast agent into the major neck veins and use of a left-arm injection site during computed tomographic (CT) angiography of the carotid arteries.

METHODS

A total of 364 patients underwent 4-section carotid CT angiography performed with an injection into the right (n = 183) or left (n = 181) arm. We calculated the volume of refluxed contrast medium and measured the retrosternal distance measured as the shortest distance between the sternum and the arch or its branches. Nine patients underwent follow-up CT angiography weeks later by using the side of injection not used before for comparison.

RESULTS

The amount of refluxed contrast medium was greater with left-arm injection than with right-arm injection (P < 0.001). With left-arm injection, the volume was significantly correlated with the retrosternal distance (r = -0.514, P < 0.001), even after we adjusted for age and sex in the linear regression model (P < 0.001). Five of the 9 patients who received injections in both arms had no reflux of contrast medium, whereas 4 patients had obvious reflux after left-arm but not right-arm injection.

CONCLUSION

Normal compression of the left brachiocephalic vein due to a developmental decreased retrosternal space may degrade carotid CT angiograms because of reflux of contrast material into the cervical veins. This degradation can be avoided if right-arm injection is used.

Massive jugular and dural sinus reflux associated with cerebral death

Radionuclide cerebral angiograms demonstrated massive jugular venous reflux in two children with clinical and electroencephalographic evidence of cerebral death. With an antecubital injection, the tracer flowed up the jugular vein, through the transverse dural sinus, and down the contralateral jugular vein. No arterial flow was seen. We hypothesize that this unusual pattern reflects the absence of normal antegrade flow through the venous system. The appearance of jugular reflux is distinct from arterial flow and should not be confused with it. These cases illustrate communication between the systemic venous system and the dural sinuses. Although this pattern in not diagnostic of cerebral death, the appearance of radiotracer in the dural sinuses does not establish the presence of cerebral perfusion.