A necropsied case of Machado-Joseph disease with a hyperintense signal of transverse pontine fibres on long TR sequences of magnetic resonance images

Machado-Joseph disease refers to autosomal dominant spinocerebellar degeneration, and the gene responsible for the disease exhibits an expanded trinucleotide CAG repeat in chromosome 14q32.1.1 Machado-Joseph disease has a wide range of clinical manifestations in addition to the cerebellar ataxia. The diverse disorders are characterised neuropathologically by the involvement of the pallidoluysian, dentatorubral, pontocerebellar, cochleocerebellar, and spinocerebellar systems, lower motor neurons, and dorsal root ganglia. Previous MRI studies disclosed only mild cerebellar and brain stem atrophy in Machado-Joseph disease.2 Our MRI examinations in 31 cases disclosed atrophy of the pons, middle, and superior cerebellar peduncles, and frontal and temporal lobes, together with fourth ventricular dilatation.3 A third of the cases displayed a hyperintense signal of the transverse pontine fibres, which had been found previously in patients with olivopontocerebellar atrophy.4Here, we report on a patient with Machado-Joseph disease with an abnormal pontine signal on MRI, nine months before death, and pathological findings of the necropsied brain. A 46 year old man had been in good health until the age of 23 when he began to stagger and slur his speech. He showed progressive difficulty in walking and was bedridden at the age of 37. Eight years later, he was admitted to hospital because of dysphagia and dysarthria. His father had had Machado-Joseph disease and …