January 3, 2019
A 30-year-old woman with a history of stroke at age 5 with intractable epilepsy.
Dyke-Davidoff-Masson Syndrome with Crossed Cerebellar Atrophy
- Background
- Originally described by Dyke, Davidoff, and Masson in 1933 with regard to plain radiographic skull changes.
- Dyke-Davidoff-Masson Syndrome (DDMS) now reflects a broader group of cross-sectional imaging findings resulting from either primary/congenital unilateral cerebral hypoplasia or secondary processes such as cerebrovascular lesion, inflammatory process, or trauma causing unilateral cerebral atrophy.
- Crossed cerebellar diaschisis (CCD) typically diagnosed with PET or MR perfusion describes cerebellar hypometabolism due to disruption of the corticopontine-cerebellar tract fibers functionally disconnecting the contralateral cerebral cortex due to a large, supratentorial lesion such as a stroke, tumor, AVM, hemorrhage or encephalitis.
- Crossed cerebellar atrophy (CCA) is rare sequelae of CCD, reflecting the spectrum of a continuous biological process.
- Clinical Presentation
- In DDMS, patients typically have unilateral cerebral hemispheric volume loss due to fetal or early life insult, usually prior to age 3. There is ipsilateral paranasal sinus hyperpneumatization and ipsilateral calvarial thickening.
- Associated findings might include ipsilateral wallerian degeneration. Clinically, patients can experience contralateral hemiplegia or hemiparesis, facial asymmetry, and mental retardation.
- Key Diagnostic Features
- In DDMS, cross-sectional imaging findings include ipsilateral skull thickening with widening of the diploic marrow space, ipsilateral frontal sinus, ethmoidal and mastoid air cell enlargement, elevation of the petrous ridge, and ipsilateral falcine displacement.
- In CCA, there is unilateral cerebellar volume loss contralateral to the supratentorial atrophy.
- Differential Diagnosis
- Sturge-Weber syndrome: FLAIR hyperintense sulci (“ivy sign”) shows leptomeningeal enhancement with contrast. Gliosis is a late finding.
- Rasmussen encephalitis: Can be similar in appearance with lobar or hemispheric volume loss in late phase. Early phase may show FLAIR hyperintense cortex and subcortical white matter with blurring of the gray-white junction and gyral swelling.
- Hemimegalencephaly: Describes enlarged dysplastic hemisphere or portion of hemisphere so the contralateral “normal” side may be mistaken for atrophy.
- Large MCA infarction: Very similar in appearance with encephalomalacia and gliosis and compensatory enlargement of the ipsilateral ventricle.
- Treatment
- A hemispherectomy can be performed for intractable seizures with an approximately 85% success rate.
