Diffusion tensor imaging of the cortico-ponto-cerebellar pathway in patients with adult-onset ataxic neurodegenerative disease
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We sought to determine whether diffusion-tensor imaging (DTI) can detect in vivo axonal damage in the corticopontocerebellar pathway of patients with adult-onset ataxic neurodegenerative disease.
Conventional MRI and DTI were performed on 18 patients with adult-onset ataxic neurodegenerative disease and 28 age-matched control subjects. Fractional anisotropy (FA) and the mean diffusivity (MD) were measured in the ventral, central, and dorsal pons, middle cerebellar peduncle (MCP) and internal capsule to evaluate corticopontocerebellar projection. Changes in FA and MD values were compared between patients and controls. Clinical disability was assessed according to the International Cooperative Ataxia Rating Scale (ICARS). The relationship between DTI measurements and ICARS was studied. Follow-up MRI was performed in five patients approximately 1 year later.
FA values were significantly lower in the ventral and central portions of the pons, MCP, and internal capsules than in these areas in control subjects (P < 0.05) with the lower FA values correlating with poorer ICARS (r > −0.57, P < 0.05). MD values were elevated in these areas, but the differences were smaller than for the FA values. No relationship was observed between the MD and ICARS. In the five patients who underwent the follow-up study, there were significant decreases between the initial study and the follow-up DTI study for FA in the MCP and internal capsule (P < 0.05).
DTI can demonstrate a degenerated corticopontocerebellar pathway in patients, and FA values can be correlated with ataxia severity. DTI may be a clinically useful tool as a quantitative surrogate marker for monitoring disease progression.
KeywordsDiffusion tensor imaging Cortico-ponto-cerebellar pathway Neurodegenerative disease Ataxia Fractional anisotropy
Conflict of interest statement
We declare that we have no conflict of interest.
- 1.Graham DI, Lantos P (eds) (2002) Greenfield’s neuropathology, 7th edn. Arnold, London, pp 343–346, 359–372Google Scholar
- 2.Iwabuchi K, Tsuchiya K, Uchihara T, Yagishita S (1999) Autosomal dominant spinocerebellar degenerations. Clinical, pathological, and genetic correlations. Rev Neurol (Paris) 155(4):255–270Google Scholar
- 8.Savoiard M, Strada L, Girotti F et al (1990) Olivopontocerebellar atrophy: MR diagnosis and relationship to multisystem atrophy. Radiology 174:693–696Google Scholar
- 24.Shimony JS, McKinstry RC, Akbudak E et al (1994) Quantitative diffusion-tensor anisotropy brain MR imaging: normative human data and anatomic analysis. Radiology 212:770–784Google Scholar
- 28.Yagishita A (1999) MRI of spinocerebellar degeneration (in Japanese). J Clin Radiol 44:1295–1303Google Scholar
- 29.le Bihan D (2006) Looking into the functional architecture of the brain with diffusion MRI: functional and molecular imaging of stroke and dementia – updates in diagnosis, treatment, and monitoring. In: Nishimura T, Sorensen AG (eds) Proceedings of the International Symposium on Functional and Molecular Imaging of Stroke and Dementia, Kyoto, Japan, 14 and 15 October 2005. International Congress Series, vol. 1290 (Radiology), pp 1–24. Elsevier, AmsterdamGoogle Scholar