Idiopathic normal-pressure hydrocephalus: temporal changes in ADC during cardiac cycle
Naoki Ohno1, Tosiaki Miyati, Mitsuhito Mase
1Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, 5-11-80, Kodatsuno, Kanazawa, Ishikawa 920-0942, Japan.
Radiology
|September 9, 2011
Summary
Idiopathic normal-pressure hydrocephalus (INPH) shows significantly higher apparent diffusion coefficient (ADC) fluctuations during the cardiac cycle compared to other conditions. This finding may aid in diagnosing INPH noninvasively.
Area of Science:
- Neurology
- Radiology
- Medical Imaging
Background:
- Idiopathic normal-pressure hydrocephalus (INPH) is a neurological condition characterized by enlarged ventricles.
- Distinguishing INPH from ex vacuo ventricular dilatation is crucial for appropriate treatment.
- Standard apparent diffusion coefficient (ADC) measurements may not fully capture the pathophysiology of INPH.
Purpose of the Study:
- To investigate temporal changes in ADC over the cardiac cycle in patients with INPH.
- To compare these ADC fluctuations between INPH patients, those with ex vacuo ventricular dilatation, and healthy controls.
Main Methods:
- Prospective study involving 13 INPH patients, 8 with ex vacuo ventricular dilatation, and 10 healthy controls.
- Electrocardiographically triggered diffusion echo-planar MRI at 1.5 T was used.
- Apparent diffusion coefficient (ADC) fluctuations (ΔADC) were calculated over 20 cardiac phases.
Main Results:
- Mean ΔADC was significantly higher in the INPH group compared to both ex vacuo and control groups (P < .01).
- No significant difference in ΔADC was observed between ex vacuo and control groups (P = .86).
- No significant differences in mean diastolic ADC were found among the groups.
Conclusions:
- Temporal ADC fluctuations over the cardiac cycle may provide novel, noninvasive diagnostic information for INPH.
- This method could potentially improve the diagnostic accuracy for suspected INPH.
- Further research into cardiac-cycle-dependent ADC changes may enhance understanding and diagnosis of INPH.
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