A two-year-old Sudanese male was presented in neurology clinical department with delayed growth and development, and seizures. Then referred to radiology department. Non-contrast magnetic resonance imaging scan of brain axial, saggital and coronal. T1-weighted, T2-weighted, fluid attenuation inversion recovery (FLAIR) and diffusion weighted imaging (DWI) were done (Figure 1A–D). Images showed well defined intracranial cyst on left frontoparietal region connected with the ipsilateral lateral ventricle, associated with diffuse brain atrophic changes in term of dilatation of ventricular system, prominent cortical sulci and dilated extra-axial cerebrospinal fluid spaces.

The intracranial cyst margin not lined by a grey matter and is associated with a small amount of adjacent FLAIR hyper-intensities, no restricted diffusion noted in DWI. No soft tissue mass lesions. No intracerebral blood degradation products. Normal brainstem and cerebellum. Findings are impressive of congenital diffuse brain atrophic changes associated with significant left sided porencephalic cystic changes as described above.

Porencephaly is an extremely rare disorder involving encephalomalacia [1]. It has been classified as congenital or acquired. The congenital form is due to localize agenesis of the cortical mantle resulting in the formation a cavity or a lateral slit through which the lateral ventricle communicate with the convexity of the brain. The cavity is lined by ependyma and laterally by a thin pia-ependymal layer. The acquired type is secondary to any type of cerebral destructive process, ranging from trauma to infection. Sometimes called false porencephalic cyst [2].

Patients with severe cases of porencephaly suffer epileptic seizures and developmental delays, whereas patients with a mild case of porencephaly display little to no seizures and healthy neurodevelopment. Infants with extensive defects show symptoms of the disorder shortly after birth [3].

Porencephalic diagnosis by magnetic resonance imaging, ultrasound and computed tomography scans. Magnetic resonance imaging scan of brain is the most sensitive and specific of the imaging techniques in children and adults. Because its sensitivity to distinguish porencephaly from open lipped schizencephaly, by absent of grey matter and associated with a small amount of adjacent FLAIR hyperintensity [4]. Porencephalic cyst should be differentiated from the neuroglial cyst, arachnoid cyst, interhemispheric cyst and holoprosencephaly. Neuroglial cyst is not communicating with the ventricles or subarachnoid space. Arachnoid cyst is extra axial in location and underlying grey-white matter is normal. Holoprosencephaly is due to normal neuronal separation, where fused thalami and monoventricles seen [5]. As of now, there is no definite cure for porencephaly. Research is still ongoing as to the causes of it and how to treat it. As of now, treatment is mainly supportive and consists: medications in the form of anticonvulsants are given to control the seizures. For infants with hydrocephalus due to porencephaly, use of a ventriculoperitoneal (VP) shunt is advised to remove excess fluid from the brain. The porencephaly patient can also undergo surgery for complete removal of the cyst from the cerebral hemisphere [6] .

Magnetic resonance imaging scan of brain play important role to distinguish porencephalic cyst from other intracranial cyst.

1. Hussain T, Bhat JA, Shoib S, Shafat M, Mushtaq R, Malla AA. Psychosis in a patient with porencephaly: A case report. J Pioneer Med Sci 2015;5(1):26–8.    
2. Sutton D. Textbook of Radiology and Imaging. 7ed. United States: Elsevier Science LTD; 2003. p. 1734.    
3. Cerquiglini A, Seri S, Sturniolo MG, Galletti F. Computerized electroencephalographic assessment of congenital brain infarction. Childs Nerv Syst 1994 May;10(4):252–8.   [Pubmed]    
4. https://radiopaedia.org/cases/porencephalic-cyst    
5. Pokhraj PS, Jigar JP, Chetan M, Narottam AP. Congenital porencephaly in a new born child. J Clin Diagn Res 2014 Nov;8(11):RJ01–2.   [CrossRef]   [Pubmed]    
6. https://www.epainassist.com/brain/porencephaly