White matter abnormalities in patients with treated hyperphenylalaninemia: Magnetic resonance relaxometry and proton spectroscopy findings
| Autor: | Christoph Oberwittler, Harald E. Möller, Ulrich Bick, Gerhard Schuierer, Albert C. Ludolph, Josef Weglage, Ulrich Stöber, Kurt Ullrich, Udo Wendel |
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| Jazyk: | angličtina |
| Rok vydání: | 1993 |
| Předmět: |
Adult
Male Pathology medicine.medical_specialty Relaxometry Magnetic Resonance Spectroscopy Adolescent Phenylalanine Neurological examination White matter Myelin Hyperphenylalaninemia Phenylketonurias medicine Humans Clinical significance Evoked potential Amino Acid Metabolism Inborn Errors Brain Diseases medicine.diagnostic_test business.industry Brain Magnetic resonance imaging medicine.disease Magnetic Resonance Imaging medicine.anatomical_structure Pediatrics Perinatology and Child Health Female Nuclear medicine business |
| Zdroj: | European Journal of Pediatrics |
| Popis: | In order to further clarify the pathogenesis and clinical significance of MRI white matter abnormalities in treated hyperphenylalaninaemia (HPA), ten patients (seven type I HPA, two type II and one type III) underwent T2 relaxometry (n = 8) and/or 1H spectroscopy (n = 7) in addition to conventional MR spin-echo imaging at 1.5 T. Two patients with severe MRI abnormalities had repeat examinations during and after a 6- to 8-month period of strict diet control. The clinical evaluation included a detailed neurological examination. In nine out of ten patients visual evoked potentials (VEP) were obtained parallel to the MR examination. MR imaging demonstrated typical symmetrical areas of prolonged T2 relaxation time predominantly in the posterior periventricular white matter in all but one of type I and II patients. There was no consistent relationship between MRI findings and time of diagnosis/initiation of therapy, IQ or visual evoked potential changes. MRI abnormalities tended to be more severe in patients with poor dietary control and high current plasma phenylalanine levels, whereas a normal MRI was found only in patients with plasma phenylalanine levels continuously below 0.36 mmol/l. There was marked regression of MRI abnormalities already after 3 months of strict diet control. T2 relaxometry showed a bi-exponential behaviour of T2 in the affected white matter, with a slow component of about 200-450 ms, indicating an increase in free (extracellular) water. 1H spectroscopy revealed no signs of severe neuronal damage. We conclude, that the observed white matter changes in treated HPA probably represent reversible structural myelin changes rather than permanent demyelination. |
| Databáze: | OpenAIRE |
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