Definition: – hydrocephalus is the abnormal accumulation of the CSF in the intracranial space. It occurs due to imbalance between production and absorption of CSF or due to obstruction of the CSF pathway. It results in dilatation of the cerebral ventricles and enlargement of the head.

Etiology: – it may occur due to congenital or acquired-
Congenital hydrocephalus-
Intrauterine infection, brain tumor obstruction, intracranial hemorrhage, malformation of arachnoid villi etc.
Acquired hydrocephalus-
Inflammation, trauma, neoplasm, hypervitaminosis A, connective tissue disorder, arterio-venous malformation etc.
Types: – there are mainly two types-
Communicating hydrocephalus:-
There is no blockage between ventricular system, the basal cisterns & the spinal subarachnoid space. There may be failure in the absorption of CSF or excessive production of CSF as in choroid plexus papiloma, pseudotumor, etc.
Non-communicating hydrocephalus:-
There is obstruction at any level in the ventricular system, commonly at the level of aqueduct or at foramina luschka and or magendie. The obstruction may be partial, intermittent or complete. It develops mainly due to inflammation and developmental obstructive lesions.
Pathophysiology:-
The ventricular system becomes greatly distended and dilated

Increase intaventricular pressure leads to thinning of cerebral cortex and cranial bones
Ependymal lining of ventricles is disrupted resulting in periventricular ooze

Sub-ependymal edema occurs edema occurs and white matter is compressed

Downward bulging of third ventricle compresses the optic nerves and hypophysis cerebri with dilation of sella turcica

Cortical atrophy may also occur

Clinical features:-
• Excessive enlargement of head
• Delayed closer of anterior fontanel
• Open sutures
• Increased intracranial pressure and alteration in muscle tone
• Delayed head holding in infants
• Protruding forehead
• Shiny scalp with prominent scalp vein
• Sun-set sign of eyes
• Cracked pot sign
• Increased head circumference
• Convulsions personality changes etc.
Diagnostic evaluation:-
• CT scan
• MRI
• USG
• Encephalography
• X-ray

MANAGEMENT:-
Directed Towards:-
a. Relief of hydrocephalus or reduce the intracranial pressure
b. Prevention or management of complications
c. Managing problems caused by the pathology
There are several types of shunts which performed in hydrocephalus:-
 Ventriculoatrial Shunt Placement
 Lumboperitoneal Shunt Placement
 Ventriculoperitoneal Shunt Tap
 Ventriculopleural Shunt Placement
 Ventriculoatrial Shunt Placement
 Ventriculoureteric Shunt Placement

Definition: –
Spina bifida, which means “cleft spine,” is characterized by the incomplete development of the brain, spinal cord, and/or meninges.
Etiology: –
The exact cause of spina bifida remains a mystery. No one knows what disrupts complete closure of the neural tube, causing this malformation to develop. Suspect factors that cause spina bifida are multiple:-
• Genetic
• Nutritional – insufficient intake of folic acid—a common B vitamin—in the mother’s diet is a key factor in causing spina bifida and other neural tube defects. Prenatal vitamins typically contain folic acid as well as other vitamins.
• Environmental factors all play a role.
Types: –

Spina Bifida Occulta: –
Occulta is the mildest and most common form in which one or more vertebrae are malformed. It indicates that a layer of skin covers the malformation, or opening in the vertebrae. This form of spina bifida, present in 10-20 percent of the general population, rarely causes disability or symptoms.

Spina Bifida Cystica: –
Closed neural tube defects make up the second type of spina bifida.It also called as spina bifida cystic. This form consists of a diverse group of defects in which the spinal cord is marked by malformations of fat, bone, or meninges.
There are mainly two types: –
Meningocele: –
spinal fluid and meninges protrude through an abnormal vertebral opening; the malformation contains no neural elements and may or may not be covered by a layer of skin. Some individuals with meningocele may have few or no symptoms while others may experience such symptoms as complete paralysis with bladder and bowel dysfunction.
Myelomeningocele: – the fourth form, is the most severe and occurs when the spinal cord/neural elements are exposed through the opening in the spine. The impairment may be so severe that the affected individual is unable to walk and may have bladder and bowel dysfunction.
Management: –
Surgical management- Meningocele involves surgery to put the meninges back in place and close the opening in the vertebrae. Myelomeningocele also requires surgery, usually within 24 to 48 hours after birth.
Performing the surgery early can help minimize risk of infection that’s associated with the exposed nerves and may also help protect the spinal cord from additional trauma.
During the procedure, a neurosurgeon places the spinal cord and exposed tissue inside the baby’s body and covers them with muscle and skin. Sometimes a shunt to control hydrocephalus in the baby’s brain is placed during the operation on the spinal cord.
Treatment doesn’t end with the initial surgery, though. In babies with myelomeningocele, irreparable nerve damage has already occurred and ongoing care from a multidisciplinary team of surgeons, physicians and therapists is usually needed. Babies with myelomeningocele may need further care for a variety of complications.