Idiopathic Parkinson's disease (IPD) remains one of those neurodegenerative diseases for which the cause remains unknown. Many clinically diagnosed cases of IPD are associated with cerebrovascular disease and white matter hyperintensities (WMHs). The purpose of this study was to investigate the presence of transverse sinus and extracranial venous abnormalities in IPD patients and their relationship with brain WMHs.
Methods
Twenty-three IPD patients and 23 age-matched normal controls were recruited in this study. They had conventional neurologic magnetic resonance structural and angiographic scans and, for blood flow, quantification of the extracranial vessels. Venous structures were evaluated with two-dimensional time of flight; flow was evaluated with two-dimensional phase contrast; and WMH volume was quantified with T2-weighted fluid-attenuated inversion recovery. The IPD and normal subjects were classified by both the magnetic resonance time-of-flight and phase contrast images into four categories: (1) complete or local missing transverse sinus and internal jugular veins on the time-of-flight images; (2) low flow in the transverse sinus and stenotic internal jugular veins; (3) reduced flow in the internal jugular veins; and (4) normal flow and no stenosis.
Results
Broken into the four categories with categories 1 to 3 combined, a significant difference in the distribution of the IPD patients and normal controls (?2 = 7.7; P < .01) was observed. Venous abnormalities (categories 1, 2, and 3) were seen in 57% of IPD subjects and in only 30% of controls. In IPD subjects, category type correlated with both flow abnormalities and WMHs.
Conclusions
From this preliminary study, we conclude that a major fraction of IPD patients appear to have abnormal venous anatomy and flow on the left side of the brain and neck and that the flow abnormalities appear to correlate with WMH volume. Studies with a larger sample size are still needed to confirm these findings.
Clinical Relevance
Magnetic resonance imaging is a powerful tool to study the venous structural abnormalities, to quantify blood flow, and to quantify the number and volume of brain white matter lesions. Correlations between the venous anatomical and flow abnormalities and white matter hyperintensities in the patients with Parkinson's disease were found in this study. These findings may prove to be an important means to subclassify patients with idiopathic Parkinson's disease. Study of those patients with idiopathic Parkinson's disease with venous structural and flow abnormalities may help understand more about the etiology or progression of the disease.