Colpocephaly
| Colpocephaly | |
|---|---|
 | |
| Embryonic brain | |
| Specialty | Neurology |
Colpocephaly is a
Symptoms
There are various symptoms of colpocephaly and patients can experience effects ranging from mild to severe. Some patients do not show most of the symptoms related to colpocephaly, such as psychomotor abnormalities and agenesis of the corpus callosum. In some cases, signs appear later on in life and a significant number of children only develop minor disabilities. The following list includes common symptoms of colpocephaly.[3][4][5]
- partial or complete agenesis of the corpus callosum
- intellectual disability
- motor abnormalities
- visual defects such as, crossing of the eyes, missing visual fields, and optic nerve hypoplasia
- spasticity
- seizures
- cerebral palsy
Intracranial abnormalities include:
- Microcephaly
- Agenesis of the corpus callosum
- Meningomyelocele
- Lissencephaly
- Periventricular leukomalacia (PVL)
- Enlargement of the cisterna magna
- Cerebellar hypoplasia
Causes
There is no known definitive single mechanism that causes colpocephaly. However, researchers believe there are many possible causes of colpocephaly. It is a common symptom of other
Some of the central nervous system disorders which are associated with colpocephaly are as follows:[3]
- polymicrogyria
- Periventricular leukomalacia (PVL)
- intraventricular hemorrhage
- Hydrocephalus
- schizencephaly
- microgyria
- microcephaly
- Pierre-Robin syndrome
- Neurofibromatosis
Often colpocephaly occurs as a result of
The most generally accepted theory is that of neuronal migration disorders occurring during the second to fifth months of fetal life. Neuronal migration disorders are caused by abnormal
- continuation of oral contraceptives
- exposure to alcohol
- intrauterine malnutrition
- intrauterine infections such as toxoplasmosis
- maternal drug ingestion during early pregnancy such as corticosteroids, salbutamol, and theophylline
Researchers also believe that these factors can cause destruction of neural elements that have previously been normally formed.[9]
It is suggested that the underdevelopment or lack of white matter in the developing fetus could be a cause of colpocephaly. The partial or complete absence of white matter, also known as
Colpocephaly has been associated with
Diagnosis
Presentation
Colpocephaly is characterized by disproportionately large occipital horns of the lateral ventricles (also frontal and temporal ventricles in some cases). MRI and CT scans of patients demonstrate abnormally thick
The lemon sign on CT scans of patients refers to the shape of the fetal skull when the frontal bones lose their normal convex contour and appear flattened or inwardly scalloped. This gives the skull a shape similar to that of a lemon. The sign is seen on transverse
Prenatal
Diagnosing colpocephaly prenatally is difficult because in many cases signs start to appear after birth. Prenatal diagnosis is made by detecting enlargement of either or both occipital horns of the lateral ventricles. Usually prenatal ultrasounds don't show cephalic abnormalities and in cases that they do show abnormality is of low accuracy, making it difficult to diagnose colpocephaly. Often, abnormalities in prenatal ultrasounds can be misdiagnosed as hydrocephalus.[2]
Postnatal
After birth, MR imaging can be done to look for cephalic abnormalities. This is the most commonly used method for diagnosing colpocephaly. Physicians look for abnormally large occipital horns of the lateral ventricles and diminished thickness of white matter.[12] Spinal tapping is not a preferred method for diagnosis because newborn babies with colpocephaly or hydrocephaly have open fontanelles which makes it difficult to collect CSF. Also, colpocephaly is not associated with increased pressure.[13]
Treatment
Colpocephaly is usually non-fatal. There has been relatively little research conducted to improve treatments for colpocephaly, and there is no known definitive treatment of colpocephaly yet. Specific treatment depends on associated symptoms and the degree of dysfunction. Anticonvulsant medications can be given to prevent seizure complications, and physical therapy is used to prevent contractures (shrinkage or shortening of muscles) in patients that have limited mobility. Patients can also undergo surgeries for stiff joints to improve motor function. The prognosis for individuals with colpocephaly depends on the severity of the associated conditions and the degree of abnormal brain development.[13]
A rare case of colpocephaly is described in literature which is associated with macrocephaly instead of microcephaly. Increased intracranial pressure was also found in the condition. Similar symptoms (absence of corpus callosum and increased head circumference) were noted as in the case of colpocephaly that is associated with microcephaly. A bi-ventricular peritoneal shunt was performed, which greatly improved the symptoms of the condition. Ventriculo-peritoneal shunts are used to drain the fluid into the peritoneal cavity.[9]
History
These brain abnormalities were first described by Benda in 1940 as 'vesiculocephaly'. In 1946, Yakovlev and Wadsworth coined the term colpocephaly from the Greek word kolpos (hollow) and kephalos (head).[citation needed] It was suggested that the enlargement of ventricles occurred as a result of white matter development arrest during early fetal life.[4] They stated that "in the apparent dilatation of the occipital horns...it represented a failure of development of the cerebral wall with persistence of the embryonal vesicular character of the brain." Yakovlev meant for this term to apply to the result of disturbances during the development of the brain. He suggested the term 'hydrocephalus ex vauco' to be used for enlargement of the occipital horns of the lateral ventricles as a result of damage to the brain after it is normally formed. However, today the term colpocephaly is used to describe both the situations.[7]