الفهرس 
Introduction and aim of workOnly 14 pages are availabe for public view
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Abstract
Hydrocephalus is commonly defined as a pathologic increase in the cerebral ventricular volume. It’s due to imbalance between the formation of CSF and its absorption.
The incidence of hydrocephalus varies between 0.3 and 1.0/1,000 births, Raised intracranial pressure (ICP( leads to severe damage to the brain parenchyma but can be silent without the presence of any signs or symptoms. Therefore, new noninvasive, detection methods are needed to diagnose these cases early .
Diagnosis and follow up of infantile hydrocephalus could be done by many radiological modalities like TCDUS ,CT and MRI . The CT and MR imaging equipment may not be universally available, neonates may be too unstable to leave the intensive care unit in addition to the hazards of CT radiation and so Sonography is considered an essential investigation in such situations .
Representative TCUS coronal views should be obtained from various angulations of the transducer from its position over the anterior fontanel. Anterior Coronal views with anterior angulation should include the frontal lobe and frontal horns of the lateral ventricles, as well as portions of the frontal, parietal, and temporal lobes; the basal ganglia; and the body of the lateral ventricles. Posterior coronal views should include the posterior portions of the temporal lobes, the occipital lobes, and the subtentorial posterior fossa area as well as the posterior portions of the ventricular system.
Representative TCUS sagittal views with appropriate degrees of left or right angulation should include the Sylvian fissures; each lateral ventricle and its choroid plexus, including the surrounding white matter; and the germinal matrix region, including the caudothalamic groove. A midline sagittal view should include the corpus callosum, the cavum septi pellucidi and cavum vergae extension (if present), the third ventricle, the area of the aqueduct of Sylvius, the fourth ventricle, the vermis of the cerebellum, and the cisterna magna.
Additional views, if necessary, may be taken through the posterior fontanel or mastoid fontanel, the foramen magnum, any open suture, or thin areas of temporoparietal bone. The trans temporal approach may also be used to visualize the circle of Willis and its major branches.
Transcranial ultrasound is the primary imaging modality employed in the assessment of infantile hydrocephalus .there is good correlation between lateral ventricular indices like (VI,FHW,FHR&TOD) and intracranial pressure .
The hemodynamic changes of cerebral circulation can be assessed by means of transcranial Doppler (TCD) that allows direct visualization of blood flow at cerebral arteries. There is good correlation between Doppler parameters especially resistive index (RI) and pulsatility index (PI) of cerebral arteries and intracranial pressure (ICP).
Accurate diagnosis of infants with hydrocephalus they are in need to VP shut insertion is very important as when the ICP is normal or only minimally elevated the risks for drainage don’t outweigh the benefits and therefore the drainage is contraindicated and on the other hand any delay in shunt insertion in cases with progressive hydrocephalus may lead to severe irreversible brain damage.
The rationale for insertion of VP shunt in hydrocephalus is currently the presence of clinical signs and symptoms of increased ICP and the progression of ventricular enlargement on consecutive imaging studies (CT,MRI and TCUS).
In infants signs and symptoms of increased ICP are confusing and easily missed ,also detection of the progression of ventricular enlargement by CT or MRI needs the presence of base line films for comparison ,leads to exposure of the infants harmful radiation in case of CT and the MRI machines are not available in many health care centers .
After shunt insertion close follow up is highly recommended to detect cases of shunt malfunction as early s possible to prevent complications of increased ICP.
In all these situations TCDUS can be used easily and safely to detect the need of shunts and also in follow up of shunts after insertion to detect cases of shunt malfunction early.
In conclusion, TCDUS has been a major advance in the diagnosis, follow up of cases of infantile hydrocephalus with early detection of shunt malfunction , it is portable safe, non-invasive, low cost and highly effective technique that is of considerable value in evaluation of infantile hydrocephalus and should be included within integrated approach to CNS imaging in these neonates.