Cerebrospinal fluid is a clear, colorless fluid that circulates in the cranial and spinal subarachnoid spaces, located between the pia and arachnoid matters. It is mainly produced by the choroid plexus, while lesser amount produced by the ependymal cells lining the ventricles. Its function includes cushioning and lubrication of the central nervous system, circulation of nutrients and waste collection providing basic mechanical and immunological protection to the brain.

There are several disorders such as communicating and non- communicating hydrocephalus, normal pressure hydrocephalus, cystic cerebrospinal fluid collections, Chiari malformation, syringomyelic cyst and arachnoid cyst that can change the cerebrospinal fluid dynamics.

Rapid advances in imaging techniques have remarkably improved the diagnosis and treatment of these disorders.

Phase contrast magnetic resonance imaging is a rapid, simple and non-invasive technique which is sensitive to even small cerebrospinal fluid flows, and can be used to evaluate cerebrospinal fluid flow both qualitatively and quantitatively. Cine phase contrast magnetic resonance images show cerebrospinal fluid flow in a dynamic, more easily appreciable, and in a more pleasing manner, allowing the delineation of obstruction, if present, along the portions of cerebrospinal fluid pathway where obstruction is common.

Phase contrast magnetic resonance imaging can be used to discriminate between communicating hydrocephalus and non-communicating hydrocephalus, to localize the level of obstruction in obstructive hydrocephalus, to determine whether arachnoid cysts communicate with the subarachnoid space, to differentiate between arachnoid cysts and subarachnoid space, to discriminate between syringomyelia and cystic myelomalacia, and to evaluate flow patterns of posterior fossa cystic malformations.

This imaging method can also provide significant information in pre-operative evaluation of Chiari 1 malformation and post-operative follow-up of patients with neuroendoscopic third ventriculostomy and ventriculoperitoneal shunt.

The application of cine phase contrast magnetic resonance imaging technique in patients with normal pressure hydrocephalus holds great promise for improvement of the diagnosis, especially in those cases where the differentiation from atrophy on clinical and conventional radiological basis is difficult.

Inclusion Criteria:

• Patients with different age groups and both sex with clinical and routine conventional magnetic resonance imaging findings suggestive of cerebrospinal fluid flow disorders.

Exclusion Criteria:

1. Patients with contraindications for MRI, e.g. an implanted magnetic device, pacemakers or claustrophobia.
2. Patients with VP shunts
3. Patients with ventriculomegally due to brain SOLs.

Patients with different age groups and both sex with clinical and routine conventional magnetic resonance imaging findings suggestive of cerebrospinal fluid flow disorders