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The Family of Gabriel Hernandez are uniting to raise money to help with his medical condition of Agenesis Corpus Collasum. Please support us

Agenesis of the corpus callosum (ACC) is an anomaly that may occur in isolation or in association with other central nervous system (CNS) or systemic malformations. Because the corpus callosum may be partially or completely absent, the term dysgenesis has also been used to describe the spectrum of callosal anomalies. The normal appearance of the corpus callosum, along with the appearance on magnetic resonance imaging (MRI) of partial and complete ACC, are shown below.
Corpus callosum, agenesis. Sagittal T1-weighted MR
Corpus callosum, agenesis. Sagittal T1-weighted MRI of the brain shows the normal appearance of the corpus callosum.Corpus callosum, agenesis. Sagittal T1-weighted MR
Corpus callosum, agenesis. Sagittal T1-weighted MRI of the brain shows complete absence of the corpus callosum. The cingulate sulcus is absent, and the medial hemispheric sulci reach the third ventricle in a radial fashion.Corpus callosum, agenesis. Sagittal T1-weighted MR
Corpus callosum, agenesis. Sagittal T1-weighted MRI of the brain shows partial agenesis of the corpus callosum. The genu and anterior body of the corpus callosum are visualized, whereas the posterior body, splenium, and rostrum are absent.Spectrum of abnormalities
ACC may be complete, partial, or atypical. With complete agenesis, the corpus callosum is totally absent.
With partial agenesis (hypoplasia), the anterior portion (posterior genu and anterior body) is formed, but the posterior portion (posterior body and splenium) is not. The rostrum and the anterior/inferior genu are also not formed.
An atypical appearance occurs when the anterior to posterior formation is not respected.
In holoprosencephaly, callosal anomalies are atypical; for example, the splenium may be present without a genu or body. In middle interhemispheric fusion, which is a variety of holoprosencephaly, the genu and splenium may be present without the callosal body.

With pseudo–corpus callosum, which involves conditions of complete or partial agenesis, the hippocampal commissure may become enlarged and appear like the posterior part of the corpus callosum.
Secondary destruction of corpus callosum occurs when the genu and anterior body are destroyed, leaving the posterior portion of the corpus callosum intact. This may occur secondary to porencephaly or schizencephaly
, as a surgical complication in cases involving the transcallosal approach to the lateral and third ventricle, or with hemisection of the callosum for the treatment of seizures.
Other cerebral malformations may coexist with callosal dysgenesis. Examples of these include interhemispheric cysts; intracranial lipomas; and disorders of neuronal migration, such as neuronal heterotopias, lissencephaly, pachygyria, and, as mentioned, schizencephaly.Preferred examination
The diagnosis of callosal agenesis depends on neuroimaging. In the newborn, before closure of the anterior fontanelle occurs, screening ultrasonography (US) may clearly show the absence of the corpus callosum; it may also show parallel lateral ventricles, interhemispheric cysts, hydrocephalus, and other related anomalies. US was the first imaging modality to allow direct sagittal imaging of callosal dysgenesis.

Antenatal diagnosis of ACC is possible from about 20 weeks' gestation. Characteristic intrauterine US findings include colpocephaly and parallel ventricular walls. Computed tomography (CT) scan findings are also diagnostic of ACC. Parallel lateral ventricles, colpocephaly, and extension of the third ventricle into the interhemispheric fissure are particularly pertinent findings. In patients with ACC who have an interhemispheric cyst, the preoperative injection of nonionic water-soluble contrast material into the cystic loculations for CT evaluation enables assessment of the ventricular system or of the communication of the cystic components with one another.
Magnetic resonance imaging (MRI) is currently the imaging procedure of choice in infants and children with ACC, even in patients who have previously undergone CT and US examinations. The multiplanar capability and high soft-tissue contrast that are possible with MRI permit confident diagnosis of ACC and its associated anomalies, especially neuronal migration anomalies or atypical forms of holoprosencephaly. These entities may be extremely subtle or indiscernible on CT or US images.Limitations of techniques
Agenesis of the corpus callosum may be depicted on CT scanning and US, but MRI is the preferred imaging modality because of its greater sensitivity for depicting associated cerebral anomalies.Next Section: Computed Tomography
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