Magnetic resonance imaging depiction of acquired Dyke-Davidoff-Masson syndrome with crossed cerebro-cerebellar diaschisis: Report of two cases.

Acquired Dyke-Davidoff-Masson syndrome, also known as hemispheric atrophy, is characterized by loss of volume of one cerebral hemisphere from an insult in early life. Crossed cerebellar diaschisis refers to dysfunction/atrophy of cerebellar hemisphere which is secondary to contralateral supratentorial insult. We describe magnetic resonance imaging findings in two cases of acquired Dyke-Davidoff-Masson syndrome with crossed cerebro-cerebellar diaschisis.

Introduction

Dyke–Davidoff–Masson syndrome refers to the loss of volume of one cerebral hemisphere which is the end result of a variety of insults which can occur in utero or early childhood (acquired cases). Clinical presentation can include hemiparesis, seizures, facial asymmetry, and mental retardation. Crossed cerebellar diaschisis refers to contralateral cerebellar dysfunction due to lesion in the contralateral cerebral hemisphere and can be transient or permanent.[12] We present magnetic resonance imaging (MRI) findings in two cases of acquired Dyke–Davidoff–Masson syndrome with crossed cerebellar diaschisis.

Case Reports

Case 1

A 28-year-old female patient with full term normal vaginal delivery had the first episode of seizures at the age of 1-year, complicated with persistent right-sided hemiparesis with mild facial asymmetry. Since then she has had several episodes of generalized tonic-clonic seizures and was treated with anticonvulsant medication which was satisfactory at first but later the seizures recurred. On clinical examination, mild mental delay, mild right-sided weakness, brisk reflexes on the right upper limbs, and a right Babinski sign were seen. No clinical evidence of cerebellar dysfunction was seen. MRI examination was performed on 1.5T scanner (Achieva, Philips Medical Systems, Netherlands). MRI revealed marked atrophy of left cerebral hemisphere with marked asymmetrical dilatation of ipsilateral lateral ventricle. There was diffuse thickening of the skull vault on left side with hyperpneumatization of left frontal and sphenoid sinuses. There was also atrophy of right cerebellar hemisphere with mild hyperintense signal on T2-weighted/fluid-attenuated inversion recovery images [Figure 1]. Based on typical MRI findings, diagnosis of acquired Dyke–Davidoff–Masson syndrome with crossed cerebellar atrophy was made.

Figure 1

(a) Axial T2-weighted image showing right cerebellar atrophy with hyperintense signal. (b and c) Axial T2-weighted images showing marked left cerebral hemiatrophy with left sided calvarial thickening and pneumosinus dilatans. (d) Coronal fluid-attenuated inversion recovery image showing marked left cerebral hemiatrophy with gliotic changes and right cerebellar atrophy with hyperintense signal

Case 2

A 10-year-old boy, known case of seizure disorder since 8 years with mild mental retardation, presented with long history of right-sided hemiparesis and a recent increase in the frequency of seizures. On examination, he had hemiatrophy of the right side of the body with spastic hemiparesis, brisk deep tendon, and extensor plantar reflexes. No clinical signs of cerebellar dysfunction were seen. There was history of meningoencephalitis at the age of 4 months. Routine hematological and biochemical investigations were within normal limits. On MRI, there was loss of volume of left cerebral hemisphere with diffuse thickening of the skull vault on left side. The mild hyperintense signal was seen in right cerebellar hemispheres which however was normal in volume [Figure 2]. Based on MRI findings, diagnosis of acquired Dyke–Davidoff–Masson syndrome with crossed cerebellar diaschisis was made.

Figure 2

(a) Axial T2-weighted image showing left cerebral hemiatrophy with left sided calvarial thickening. (b) Axial T2-weighted and (c) Coronal fluid-attenuated inversion recovery images showing hyperintense signal in right cerebellar hemisphere

Discussion

Dyke–Davidoff–Masson syndrome was first described in 1933[3] and is characterized by loss of volume of one cerebral hemisphere due to insult in fetal/early life. Prenatal causes can be vascular insult, vascular malformations, in utero infections, and congenital malformations. Perinatal and postnatal causes include perinatal/postnatal infections, tumors, trauma, and intracranial hemorrhage.[4] Postnatal hemiatrophy can develop secondary to cerebral trauma, stroke, tumors, infections, and febrile seizures. Cerebral volume loss is associated with varying degree of gliosis. Insults in later life are associated with more gliotic changes as seen in our first case who had insult at higher age and showed more marked changes of gliosis. Associated bony changes in the form of ipsilateral calvarial thickening, hyperpneumatization of ipsilateral paranasal sinuses, and mastoid air cells indicate insult in early life before 2 years of age.[2]

Crossed cerebellar diaschisis represents contralateral cerebellar hypometabolism secondary to supratentorial insult and may be reversible. It is classically diagnosed by positron emission tomography imaging but can be detected by perfusion weighted MRI before structural changes become visible on conventional MRI.[15] Crossed cerebellar atrophy is relatively rare and represents volume loss of contralateral cerebellar hemisphere along with signal alteration. It is irreversible and likely represents the continuum of the same biological process as crossed cerebellar diaschisis.[1]

Both of our patients had long history of hemiplegia and focal seizures and were well-controlled on medication. Degree of cerebellar atrophy was more severe in first patient; however, both patients did not show any evidence of cerebellar dysfunction on clinical examination. This is similar to findings of other authors and is likely related to the plasticity of the brain.[16]

Crossed cerebellar atrophy in the setting of Dyke–Davidoff–Masson syndrome is ipsilateral when insult is before the age of 1-month and in contralateral when the insult is after this age due to differences in anatomy during development.[12] This is consistent in our patients, both of them had history of insult after 1-month of age.

Conclusion

Dyke–Davidoff–Masson syndrome presents with characteristic imaging findings which are readily recognizable and provide some clue to the timing of insult. Crossed cerebellar diaschisis/atrophy may be associated with acquired Dyke–Davidoff–Masson syndrome and indicates that the timing of insult is after the age of 1-month. It is typically not associated with cerebellar dysfunction and should not be mistaken for other pathologies like infarcts.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.