In 1933, Dyke, Davidoff, and Masson described 9 patients with clinical characteristics of hemiparesis, facial asymmetry, seizures, and mental retardation noted to have pneumatoencephalographic changes on skull radiograph [4]. CT and MRI features of this entity include cerebral hemiatrophy, ipsilateral ventriculomegaly, hyperpneumatization of the sinuses on the affected side, and compensatory calvarial thickening [1, 3, 5]. Affected patients are largely from the paediatric population; however, occurrence in adult patients have been reported [3]. Common causes include congenital anomalies, perinatal hypoxia, intracranial hemorrhage, and infections [1].
Clinically, patients may have seizures, mental retardation, contralateral hemiparesis, and facial asymmetry. Our patient initially had headaches, followed by episodic complex-partial seizures. Birth history did not reveal any hypoxic-ischemic events. There was also no history to suggest intra-uterine/perinatal infection. Only after head CT, an infarct was diagnosed; and patient was treated symptomatically. The MRI that followed did not add any additional information. To the unaccustomed, subtle findings on CT/MRI may easily be missed. We were able to accurately diagnose the imaging features after consulting with Neuroradiology. Understandably, the rarity of this condition makes accurate diagnosis a challenge – as evident in our experience.
Imaging via CT and MRI proves to be of significant value; enabling correct diagnosis and institution of appropriate management. These two imaging modalities are valuable in that they provide cross sectional images, with thin slices, and post processing capabilities. Pertinent imaging features for DDMS include cerebral hemiatrophy/hypoplasia, hyperpneumatization of the paranasal sinuses, and compensatory osseous hypertrophy. These radiological features will become more evident with time, as the patient gets older. There have been reports suggesting calvarial involvement, as in our experience, points to cerebral damage occurring during the intrauterine period or before the age of 3 [6,7,8]. Our patient, interestingly, did not have the clinical history or features to suggest an early life event which may lead to cerebral damage.
In essence, due to the rarity of this syndrome, it may be easily misdiagnosed by the untrained eye. CT and MRI are powerful imaging modalities to diagnose the pertinent imaging features associated with this syndrome. Knowledge of the clinical presentation, risk factors, and imaging features is therefore indispensable for appropriate patient management.
