The rostral neuropore or anterior neuropore is a region corresponding to the opening of the embryonic

neural tube In the developing chordate (including vertebrates), the neural tube is the embryonic precursor to the central nervous system, which is made up of the brain and spinal cord. The neural groove gradually deepens as the neural fold become elevated, a ...

in the anterior portion of the developing

prosencephalon In the anatomy of the brain of vertebrates, the forebrain or prosencephalon is the Anatomical terms of location#Directional terms, rostral (forward-most) portion of the brain. The forebrain (prosencephalon), the midbrain (mesencephalon), and hin ...

. The central nervous system develops from the neural tube, which initially starts as a plate of cells in the ectoderm and this is called the neural plate, the neural plate then undergoes folding and starts closing from the center of the developing fetus, this leads to two open ends, one situated cranially/rostrally and the other caudally. Bending of the neural plate begins on day 22, and the cranial neuropore closes on day 24. giving rise to the

lamina terminalis The median portion of the wall of the forebrain consists of a thin lamina, the lamina terminalis, which stretches from the interventricular foramen (Foramen of Monro) to the recess at the base of the optic stalk (optic nerve) and contains the va ...

of the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

Failure to close

* Failure of closure of the anterior

neuropore Neurulation refers to the folding process in vertebrate embryos, which includes the transformation of the neural plate into the neural tube. The embryo at this stage is termed the neurula. The process begins when the notochord induces the formati ...

during

embryogenesis An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ...

will lead to

anencephaly Anencephaly is the absence of a major portion of the brain, skull, and scalp that occurs during embryonic development. It is a cephalic disorder that results from a neural tube defect that occurs when the rostral (head) end of the neural tube fai ...

, the failure of the brain and skull to develop. In less severe situations it may lead to different forms of encephalocele (i.e. cranium bifidum). There are three forms of cranium bifidum: mengocele, meningo-encephalocele and meningohydro-encephalocele. In which respectively protrude the meninges, the meninges and brain tissue and lastly meninges, brain tissue and cranial ventricles. * Failure of closure of the posterior neuropore (caudal neuropore) during embryogenesis will lead to

spina bifida Spina bifida (Latin for 'split spine'; SB) is a birth defect in which there is incomplete closing of the spine and the membranes around the spinal cord during early development in pregnancy. There are three main types: spina bifida occulta, me ...

. This condition is always marked by a local lack of osteogenesis, or bone growth. The reason is that the correct differentiation and placement of underlying tissues (the spinal cord and spinal nerves and associated tissues) induce the osteogenesis, even small flaws in the underlying tissues can lead to a problem in the formation of the spine (vertebrae). Occasionally spina bifida is accompanied by a protrusion of the meninges and cerebrospinal fluid (meningocele) or protrusion of meninges, cerebrospinal fluid and nerve tissue (meningomyelocele).

References

{{Authority control Embryology of nervous system