The DWI,~1H-MRS And ASL Study Of SCA3/MJD And SPG4

Background:Hereditary spinocerebellar ataxia is one of the major genetic and degenerative diseases involving the human nervous system. The pathogenic gene (MJD1) of Spinocerebellar ataxia3and the Machado Joseph disease is the same and located on the long arm of chromosome14,14q32.1. So They are also known as the SCA3/MJD. It is the most common subtype SCA in mainland China and the clinical manifestations is varied. Hereditary spastic paraplegia or familial Strti mpell-Lorrain spastic paraplegia, is a hereditary neurodegenerative diseases such as the corticospinal tract caused by. Hereditary spastic paraplegia4is the most common subtype of autosomal dominant inheritance in HSP. The main clinical manifestations characteristics are progressive lower limb spasticity, tendon reflexes hyperfunction and spastic gait. SPG4and SCA3/MJD have some overlap in clinical manifestation, which brings great difficulties to the diagnosis of the two diseases.Purpose:To investigate the value of diffusion weighted imaging, proton magnetic resonance spectroscopy and arterial spin labeling method in the diagnosis of SCA3/MJD and SPG4.Method:13cases of SPG4,38cases of SCA3/MJD which divided into22onset patients and16cases only genetic abnormalities, and27healthy volunteers were scaned with DWI,1H-MRS and ASL. The processing data were apparent diffusion coefficient value, N-acetyl aspartate, creatine, Choline-containing compounds, myo-inositol, NAA/Cr, Cho/Cr, mI/Cr ratio and raletive cerebral blood flow. The above data were grouped for comparative study. The SCA3/MJD onset patients were evaluated with the International Cooperative Ataxia Rating Scale and Ataxia Rating Scale, then calculated the correlation between ADC, NAA/Cr, Cho/Cr, ml/Cr ratio and rCBF and the clinical score.Result:In the precentral gyrus, posterior limb of internal capsule, cerebral peduncle, pons, cerebellar cortex and cerebellar white matter, the ADC of onset SCA3/MJD increased compared to control group.The ADC of not onset SCA3/MJD increased compared to control group only in the cerebellar dentate nucleus. The ADC of onset patients of SCA3/MJD was significantly higher in the posterior limb of the internal capsule, cerebellar cortex, cerebellar white matter and pons than SPG4. The NAA/Cr of onset SCA3/MJD was significantly reduced in the pons and cerebellar dentate nucleus compared to the normal control group and SPG4. The rCBF of onset SCA3/MJD had significant decrease in the pons, cerebellar dentate nucleus and cerebellar cortex compared with the control group. In the cerebellar dentate nucleus and the cerebellar cortex, the rCBF of not onset SCA3/MJD was significantly lower than the control group. The rCBF of the onset SCA3/MJD was significantly lower in the pons and cerebellar cortex than SPG4. The ADC in cerebellar cortex and NAA/Cr in cerebellar dentate nucleus of onset SCA3/MJD had obvious correlation with ICARS.Conclusion:SCA3/MJD lesions are mainly located in the cerebellum and brainstem, that gray and white matter was also involved. The the cerebellar dentate nucleus may be the earliest involved area. There is a correlation between the ICARS and the cerebellar lesion degree. The ICARS can reflect the severity of clinical manifestations. Compared with SPG4, SCA3/MJD were more severe in cerebellum and brainstem lesions. DWI,1H-MRS and ASL have a certain significance in the diagnosis of SCA3/MJD and SPG4.