Alteration of Venous Drainage Route in Idiopathic Normal Pressure Hydrocephalus and Normal Aging

Abstract

Idiopathic normal pressure hydrocephalus (iNPH) is a highly prevalent condition in the elderly population; however, the underlying pathophysiology in relation to the aging process remains unclear. To investigate the effect of removal of cerebrospinal fluid by lumbar “tap test” on the cerebral circulation in patients with iNPH, 14 patients with “probable” iNPH were studied using a novel blood tracking technique based on blood oxygenation level-dependent (BOLD) magnetic resonance signal intensity. By tracking the propagation of the low-frequency component of the BOLD signal, extended venous drainage times were observed in the periventricular region of the patients, which was reversed by tap test. Interestingly, the venous drainage time in the periventricular region exhibited an age-related prolongation in the healthy control group. Additional regression analyses involving 81 control subjects revealed a dissociation of deep and superficial venous systems with increasing age, presumably reflecting focal inefficiency in the deep system. Our results not only provide insights into the etiology of iNPH, but also point to a potential non-invasive biomarker for screening iNPH.

Normal-pressure hydrocephalus: A critical review

“…Venous hypertension in intracranial circulation hinders CSF absorption through the arachnoid villae in the dural sinuses. 60 - 64 …”

Age-Related Hearing Loss Associations With Changes in Brain Morphology

“…The lateral ventricle findings may indicate a related but different vascular mechanism. Age-related changes in venous system drainage (Chung et al., 2010; Raz, Daugherty, Sethi, Arshad, & Haacke, 2017), particularly for veins surrounding the lateral ventricles (Satow et al., 2017), can be influenced by age-related changes in arterial pulsation and compliance that disrupts CSF regulation (Bateman, 2000; Bateman, Levi, Schofield, Wang, & Lovett, 2008). This potential venous flow explanation for changes in lateral ventricle volume seems speculative but may be possible given that the change in ventricle volume did not appear to reflect a spatial accommodation of lost tissue, change in total gray matter volume × change in ventricle volume: r (29) = −.05, ns .…”

Axial variation of deoxyhemoglobin density as a source of the low-frequency time lag structure in blood oxygenation level-dependent signals

“…Moreover, gross vascular anatomy has been detected consistently in these studies, replicating the results from respiratory challenges [35,36], which importantly suggests an equivalence between the sLFO and manipulated circulatory turbulences. Apart from patient data, a recent study involving healthy participants revealed changes in venous drainage patterns with normal aging [37]. A body of evidence thus empirically supports the biological significance of the low-frequency lag structure and its underlying principles.…”