Term Paper: Schizencephaly
Brittany Pena
Midwestern State University
RADS-4773 MRI Applications
March 6, 2014
Kimberly Onstott, MSRS, R.T. (R)(CT)(MR)
Abstract
Schizencephaly is defined as a rare birth defect that involves slits or clefts in the cerebral hemispheres of the brain. This cortical malformation can affect one or both sides of the brain. The research shown here describes the symptoms of schizencephaly, how it is detected, types of schizencephaly, types of imaging done pre and postnatal, and treatment for this rare brain malformation.
What is schizencephaly?
“The term schizencephaly refers to full-thickness clefts within the cerebral hemispheres” (Barkovich and Norman, 1988, pp. 1394). Many sources define schizencephaly as a very rare cortical malformation that results in gray matter-line clefts that can impact one or both sides of the brain. “With only an estimated 7,000 cases, schizencephaly is the second rarest known brain malformation. A study in the UK found a prevalence of 1.48 for every 100,000 births” (Stang and Dr. Krucik, 2013).
In 1946, the term “schizencephaly, was first introduced by Yakovlev and Wadsworth. The term is Greek in origin; skhizin,meaning “to split”, and enkephalos, meaning “brain”. “Yakovlev and Wadsworth thought schizencephaly was a malformation caused by failure of development of brain tissue, dating back to the first two months of fetal life. Neuropathologists have dismissed the agenesis hypothesis in favor of an encephaloclastic process and have even discouraged the use of the term schizencephaly. However, the term is used by neuroradiologists, and, thanks to modern imaging, the frequency of schizencephaly appears to be considerably higher than had been previously appreciated” (Agamanolis, 2010).
An exact cause is not yet known, and little research has been done. The understanding of schizencephaly has slowly evolved as advances in imaging techniques have resulted in a steady improvement in the in vivo evaluation of the anomaly. One fact stays the same in all of the arguments over the cause of schizencephaly; there was an ischemic episode during gestation.
Symptoms of Schizencephaly
Many people with schizencephaly have uncontrollable seizures mental retardation, an abnormally small head, poor muscle tone, scoliosis, partial or complete paralysis, and low to no vision. “Symptoms of schizencephaly vary depending on whether the clefts in the brain are bilateral or unilateral. Bilateral clefts have more serious symptoms. They often result in developmental delays, and delays in learning speech and language skills. They can also cause problems with movement due to poor communication between the brain and the spinal cord. Unilateral clefts almost always produce paralysis on one side of the body. However, most people with unilateral clefts have normal to near-normal intelligence. Other symptoms of schizencephaly include being partially or completely paralyzed, poor muscle tone, or having a head that is smaller than normal. Recurring seizures are also a symptom. Too much fluid accumulating in the brain can also be a symptom” (Stang and Dr. Krucik, 2013).
Bilateral schizencephaly means there are abnormal clefts on both sides of the brain. Unilateral schizencephaly is a term where a cleft is located on only one side of the brain. Whatever side the cleft is on, will affect the opposite side of the body. A study done by Barkovich and Norman in 1987 showed that patients who had unilateral clefts with fused lips were of normal intelligence. Patients with large unilateral clefts had moderate developmental delays. And the patients with bilateral clefts had severe developmental delays. However, all of the patients that participated in the study had seizure disorders that were intractable to medical therapy, and all had motor dysfunction.
Types of Schizencephaly
There are two morphological types of Schizencephaly: open lip and closed lip. Open lip means
