
Neuroradiology
Case TypeClinical Case
Authors
Prabakaran M. S., Geetha Soliappan, Deepthi S.
Patient9 years, male
A 9-year-old boy presented to the paediatrics OPD with a recent onset of intractable seizures, myoclonic jerks and recurrent episodes of falls for over seven months. The child was not immunised. There was no history of fever, weakness, and developmental delay. EEG showed polyspikes with slow wave pattern.
Few subcortical white matter FLAIR hyperintensities in the right parietal lobe and bilateral frontal lobes (Figure 1).
Few patchy areas of asymmetrical periventricular FLAIR hyperintensities noted in bilateral fronto-parietal lobes, more in the frontal lobe (Figure 2). No abnormal meningeal/parenchymal contrast enhancement.
Mild generalised prominence of the ventricular system noted due to bilateral mild cerebral atrophy.
Background
Subacute sclerosing panencephalitis (SSPE) is a progressive neurological condition occurring predominantly in childhood and early adolescence due to persistent measles infection [1].
Though a long latent period, measles virus infection of the brain occurs soon after the acute infection with subsequent spread [2].
Clinical Perspective
Symptoms typically present 8 to 11 years after post-measles infection. On initial presentation, personality/behaviour changes with academic decline and intellectual deterioration are seen. Followed by a progressive decline in motor function with myoclonus, autonomic dysfunction, and focal paralysis. Few develop seizures, either focal or generalized, and about one-third of patients develop epilepsy. Patients eventually progress into a vegetative state or akinetic mutism, followed by death [5–7].
Imaging features are not diagnostic but for supportive evidence. Sequential MRI is useful for following the course of the disease [8]. Parenchymal lesions were significantly correlated with the duration of the disease [10].
Imaging Perspective
CT can be normal in the early stages of the disease. Diffuse cerebral oedema and small ventricles are seen at a later stage. Generalised cerebral atrophy and ex vacuo dilatation of ventricles are seen after a prolonged course [9].
MRI reveals ill-defined asymmetrical T2/FLAIR high signal intensities, more commonly seen in the occipital and parietal subcortical white matter than in the frontal region. The frontal lobe is involved in the later stages. In most cases, the grey matter is spared. In later stages, high signal changes in deep white matter with severe cerebral atrophy are seen. Mass effect and contrast enhancement of lesions are not usually seen [10].
The diagnosis of SSPE is made based on typical clinical findings, periodic EEG complexes, and elevated measles antibody titer in CSF [11].
Outcome
No adequate therapy is currently available for the treatment of SSPE. Interferon alpha, ribavirin and isoprinosine have been tried, but supportive care is the most important aspect in the management of SSPE. It is a progressive disorder, and death usually occurs in 1–3 years [1].
Take Home Message / Teaching Points
A child presenting with personality/behaviour changes, intractable seizures and frequent episodes of falls, imaging features showing ill-defined patchy subcortical occipital and parietal white matter changes, should raise suspicion of SSPE.
All patient data have been completely anonymised throughout the entire manuscript and related files.
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URL: | https://www.eurorad.org/case/18525 |
DOI: | 10.35100/eurorad/case.18525 |
ISSN: | 1563-4086 |
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