Imaging of Hydrocephalus by Ultrasound and Computerized Tomography Scanning

Abstract

Hydrocephalus is the term used for increased volume of cerebrospinal fluid within the skull. The excessive accumulation of cerebrospinal fluids results in an abnormal dilation of the ventricular system of the brain. The dilation causes potentially harmful pressure on the tissues of the brain. There are two types of hydrocephalus: (1) 1. Communicating hydrocephalus, in which the cerebrospinal fluid can flow freely from the ventricular system to the subarachnoid space. 2. Non communicating hydrocephalus, occur when the obstruction affects the passages of the cerebrospinal fluid.(2) Hydrocephalus may be congenital or acquired. Congenital hydrocephalus is present at birth and may be caused by either environmental influences or genetic predisposition. Acquired hydrocephalus can affect individuals of all ages and may be caused by injury or disease. In infancy, the most obvious indication of hydrocephalus is often the rapid increase in head size. In United States the common cause is congenital and the infectious causes show low incidence, but in Al shaab Teaching Hospital, the main cause is congenital and meningitis is the second main cause. Hydrocephalus is diagnosed through clinical neurological evaluation and using the radiological imaging techniques such as: ultrasonography, computer tomography (CT) and magnetic resonance 2 imaging (MRI). Ultrasound (U/s) can detect hydrocephalus at early age during intra-uterine life and its application is limited by the patient’s age after birth. It is cheap and safe. The other modalities can not detect the disease safely as ultrasound does. (3) computerized tomography is used to evaluate the ventricular dilatation, and to show the site of obstruction. It shows both brain tissue and cerebrospinal fluid, but can not detect the nature of the etiological factor. Moreover, it is hazardous due to x-rays, which has biological effects (4). CT scan has higher resolution than U/s Which it’s commonly used to investigate the condition under study.