Porencephaly is an extremely rare cephalic disorder involving encephalomalacia. It is a neurological disorder of the central nervous system characterized by cysts or cavities within the cerebral hemisphere. Porencephaly was termed by Heschl in 1859 to describe a cavity in the human brain. Derived from Greek roots, the word porencephaly means holes in the brain. The cysts and cavities (cystic brain lesions) are more likely to be the result of destructive (encephaloclastic) cause, but can also be from abnormal development (malformative), direct damage, inflammation, or hemorrhage. The cysts and cavities cause a wide range of physiological, physical, and neurological symptoms. Depending on the patient, this disorder may cause only minor neurological problems, without any disruption of intelligence, while others may be severely disabled or die before the second decade of their lives. However, this disorder is far more common within infants, and porencephaly can occur both before or after birth. Signs and symptoms
Patients diagnosed with porencephaly display a variety of symptoms, from mild to severe effects on the patient. Patients with severe cases of porencephaly have epileptic seizures and developmental delays, whereas patients with a mild case of porencephaly display little to no seizures and typical neurodevelopment. Infants with extensive defects show symptoms of the disorder shortly after birth, and the diagnosis is usually made before the age of 1.The following text lists out common signs and symptoms of porencephaly in affected individuals along with a short description of certain terminologies. Cause
Porencephaly is a rare disorder.
COL4A1 gene expresses a type IV collagen (basement protein) that is present in all tissue and blood vessels and is extremely important for the structural stability of vascular basement membranes. The COL4A1 protein provides a strong layer around blood vessels. The mutation can weaken the blood vessels within the brain, elevating the probability of a hemorrhage, and eventually promoting internal bleeding then leading to porencephaly during neurodevelopment of infantile stage. Therefore, the formation of cavities can be a result of hemorrhages which promote cerebral degeneration. In a mouse model, mouse with COL4A1 mutations displayed cerebral hemorrhage, porencephaly, and abnormal development of vascular basement membranes, such as uneven edges, inconsistent shapes, and highly variable thickness. Purposely causing a mutation in the COL4A1 gene caused several mouse to develop cerebral hemorrhage and porencephaly-like diseases. Though, there is no direct correlation between mutations of the COL4A1 gene, it appears that it has an influential effect on the development of porencephaly.Another genetic mutation, factor V G1691A mutation, has been reported to show possible association to the development of porencephaly. A mutation in factor V G1691A increases the risk of thrombosis, blood clots, in neonates, infants, and children. Therefore, 76 porencephalic and 76 healthy infants were investigated for factor V G1691A mutation along with other different prothrombotic risk factors. The results indicated that there was  higher prevalence of the factor V G1691A mutation in the porencephalic patient group.