Rinsho Shinkeigaku (Clinical Neurology)

Symposium 06iby non designated speakersj

A hypothesis of cerebrospinal fluid formation and absorption: from the clinical viewpoint of idiopathic normal pressure hydrocephalus

Etsuro Mori, M.D., Ph.D.1) and Shinya Yamada, M.D., Ph.D.2)

1)Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University, Graduate School of Medicine
2)Neurosurgery Service, Toshiba Rinkan Hospital

The morphological features of disproportionately enlarged subarachnoid-space hydrocephalus (DESH), the core type of idiopathic normal pressure hydrocephalus, can not be explained by the classical theory of CSF absorption at the arachnoid villi and the hypothesis of CSF flow blocking at the convexity subarachnoid spaces. By using MRI Time-SLIP CSF flow imaging, we demonstrated that CSF freely move in the subarachnoid spaces below and in the Sylvian fissures. CSF does not move in the convexity subarachnoid spaces in healthy individuals and patients with DESH, indicating the presence of flow obstacles in the convexity subarachnoid spaces by nature. If so, CSF absorption must take place below the Sylvian fissures. CSF would retain in the ventral subarachnoid spaces and ventricles, once the absorption below the Sylvian fissures is impaired. This hypothesis enables to explain the morphological features of DESH. We proposed an alternative hypothesis of CSF circulation and absorption including absorption from the cranial and spinal nerve roots to the lymphatic system.
Full Text of this Article in Japanese PDF (431K)

(CLINICA NEUROL, 54: 1190|1192, 2014)
key words: idiopathic normal pressure hydrocephalus, disproportionately enlarged subarachnoid-space hydrocephalus, CSF circulation, Time-SLIP

(Received: 21-May-14)