Magnetic resonance imaging for quantitative flow measurement in infants with hydrocephalus: a prospective study

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Raised intracranial pressure (ICP) that is associated with hydrocephalus may lead to alterations in cerebral hemodynamics and ischemic changes in the brain. In infants with hydrocephalus, defining the right moment for surgical intervention based on clinical signs alone can sometimes be a difficult task. Clinical signs of raised ICP are known to be unreliable and sometimes even misleading. Furthermore, when sutures are closed, ICP does not always correlate with the size of the ventricles or with the clinical signs or symptoms. In this study the authors investigated whether cerebral blood flow (CBF) can be measured by using quantitative MR angiography in infants with progressive hydrocephalus. In addition, the authors investigated the relationship between CBF and ICP, before and after cerebrospinal fluid (CSF) diversion.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Fifteen infants with progressive hydrocephalus (age range 1 day–7 months) were examined. All patients underwent anterior fontanel pressure measurement, MR angiography, and mean arterial blood pressure measurements before and after CSF diversion. Brain volume was measured to compensate for the physiological increase in CBF during brain maturation in infants.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>The mean preoperative ICP was 19.1 ± 8.4 cm H<jats:sub>2</jats:sub>O (± standard deviation). The mean postoperative ICP was 6.7 ± 4.0 cm H<jats:sub>2</jats:sub>O (p &lt; 0.005). The mean preoperative CBF was 25.7 ± 11.3 ml/100 cm<jats:sup>3</jats:sup> brain/min. After CSF diversion, CBF increased to 50.1 ± 12.1 ml/100 cm<jats:sup>3</jats:sup> brain/min (p &lt; 0.005). The mean arterial blood pressure did not change after surgical intervention.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Magnetic resonance imaging can be used to measure CBF in infants with hydrocephalus. Raised ICP was related to a decrease in CBF. After CSF diversion, CBF and ICP improved to values within the normal range.</jats:p></jats:sec>

Hemodynamically significant venous collapse underlying neonatal hydrocephalus

“…The method used in the present study is identical to the one suggested by Leliefeld et al 20 In 2 of the hydrocephalus cases, the CBF was very low initially (27 and 23 ml/100 g/min, similar to Leliefeld and colleagues' findings). However, in 1 case, CBF was normal at 67 ml/100 g/min.…”

“…27 Leliefeld et al used an MRI-based technique to simultaneously measure cerebral inflow via the carotid and basilar arteries and brain parenchymal volume to obtain quantitative data on CBF. 20 In a study of 15 infants from 1 day to 7 months of age, the mean CBF before shunting was 25 ml/100 g/min, which increased to 50 ml/100 g/min following treatment with a shunt. A doubling of CBF after shunting suggests a significant increase in vascular resistance before shunt placement as well as rapid improvement with a reduction in resistance post-shunt insertion.…”

Hydrocephalus Decreases Arterial Spin-Labeled Cerebral Perfusion

“…22 Recently, 2D phase-contrast MRA has shown that carotid and basilar arterial flow rates are reduced in infants with hydrocephalus. 23 However, 2D phase-contrast MRA does not directly measure CBF at the tissue level and may be hampered by long scanning times and flow-sensitive technical challenges. 24,25 In contrast, arterial spin-labeled (ASL) MR imaging perfusion directly measures tissue perfusion without requiring long scanning times, contrast, or radioisotope injection.…”

0.1T magnetic resonance image in the study of experimental hydrocephalus in rats. Accuracy of the method in the measurements of the ventricular size

“…Nowadays, magnetic resonance is already being used associated with other resources to aim of investigating pathophysiological characteristics of several diseases, mainly the neurological ones [11][12][13] . However, most studies, both experimental and clinical, use MRI equipment of field higher than 1.0T.…”