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Diffusion Tensor Magnetic Resonance Imaging in the Analysis of Neurodegenerative Diseases
Published on: July 28, 2013
Brain MRI diffusion-weighted imaging in patients with classical phenylketonuria
Renzo Manara1, Alessandro P Burlina, Valentina Citton
1Neuroradiologic Unit, University Hospital of Padua, Padua, Italy.
Neuroradiology
|August 5, 2009
Summary
Diffusion-weighted imaging (DWI) is more sensitive than T2-weighted images for grading white matter abnormalities (WMAs) in classical phenylketonuria (cPKU) patients. DWI reliably detects WMAs, correlating strongly with phenylalanine levels.
Area of Science:
- Neurology
- Radiology
- Metabolic Disorders
Background:
- Classical phenylketonuria (cPKU) is a metabolic disorder requiring early treatment.
- White matter abnormalities (WMAs) are a known complication in cPKU patients.
- Assessing WMAs aids in understanding disease progression and treatment efficacy.
Purpose of the Study:
- To grade WMAs in early-treated cPKU patients using MRI.
- To compare the sensitivity and specificity of T2-weighted and diffusion-weighted imaging (DWI) for WMA detection.
- To correlate WMA severity with phenylalanine and tyrosine levels.
Main Methods:
- Twenty early-treated cPKU patients and 26 controls underwent MRI.
- White matter abnormalities were graded using Thompson score (TS) and a novel MRI score (mTS) on T2-weighted and DWI sequences.
- Plasma phenylalanine and tyrosine concentrations were measured.
Main Results:
- No WMAs were observed in patients with Phe(year) < 460 mumol/L.
- DWI demonstrated significantly higher TS and mTS compared to T2 images in cPKU patients (p < 0.002).
- WMA severity correlated strongly with phenylalanine levels (Phe(year)) but not tyrosine levels.
Conclusions:
- Diffusion-weighted imaging (DWI) is more sensitive and reliable for detecting and grading WMAs in cPKU.
- MRI findings, particularly on DWI, are strongly associated with phenylalanine levels.
- DWI may offer a more comprehensive assessment of brain involvement in cPKU.
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