Clinical History
Cerebellar signs and symptoms evolving within the last 3-4 years.
Imaging Findings
The patient presented with ataxic gait, tremor, speech disturbance, hypotonia, evolving over the last 3-4 years. The findings were especially apparent on the left side, but also mildly observed on the right side. MR imaging study was performed on a 1.5 T MR scanner. T1 and T2 weighted sequences
were obtained in three orthogonal imaging planes. Following the MRI diagnosis of the patient, a stereotaxic biopsy of the lesion was performed under MRI guidance. The histopathological diagnosis was the same as the MRI diagnosis.
Discussion
Lhermitte-Duclos disease (LDD) is a rare pathological disorder involving the cerebellum, which is also known as dysplastic gangliocytoma of the cerebellum or diffuse hypertrophy of the cerebellar cortex. It most frequently affects young male patients. A portion of one cerebellar hemisphere is involved typically, however LDD may extend into the vermis or rarely the contralateral hemisphere. It consists of focally indolent growth of the cerebellar cortex in which the folia enlarge. The enlarged folia lose their secondary foldings and asymmetrically expand the cerebellar hemisphere. Histopathologically, LDD consists of a thick layer of abnormal ganglion cells replacing the granular layer of the cerebellar cortex, a thick hypermyelinated marginal layer, and a thin Purkinje cell layer with thinning thinning of medullary white matter. The fundamental nature of the entity and its pathogenesis remain unknown, and considerable debate has centered on whether it represents a neoplastic, malformative or hamartomatous lesion. However the associated masses have been demonstrated to enlarge over time and to recur after resection, acting much like low grade neoplasms. Patients with LDD may become symptomatic because of the mass effect from the lesion, with resultant intracranial hypertension, cerebellar signs and symptoms. But LDD may remain asymptomatic until incidentally discovered at autopsy or in an imaging for an unrelated condition. LDD produces a characteristic pattern on MRI which shows a sharply marginated cerebellar mass with T1 and T2 prolongation, coursing through the mass are curvilinear structures of gray matter intensity of cerebellar cortex. The cortical ribbon appears of normal or slightly less than normal thickness. The lesion itself does not enhance after the administration of contrast matter typically, however leptomeninges around the lesion enhance with contrast matter.
Differential Diagnosis List
