Hydrocephalus its causes and treatment

Definition

•          Hydrocephalus is defined as an abnormal accumulation of CSF within the head resulting from

•          its impaired circulation and absorption, or rarely from its increased production by a choroid plexus papilloma.

•          I- Causes of obstructive or non-communicating hydrocephalus

•          1- Congenital

•            a- Aqueductal stenosis.

•            b- Malformation of a vein of Galen that can expand to a large size causing obstruction of the CSF flow.

•            c- Dandy-walker syndrome: cystic dilatation of the fourth ventricle with atrophy of cerebellum.

•            d- Chiari malformation type II: it results in elongation of the fourth ventricle and kinking of the brain stem with displacement of the inferior vermis, pons, and medulla into the cervical canal.

•          2- Acquired

•          a- Neonatal meningitis or intracranial hemorrhage especially in a premature infant.        

•          b- Lesions of the posterior fossa are prominent causes of hydrocephalus e.g. tumor, or abscess.

•          II- Causes of non obstructive or communicating hydrocephalus

•            1-Choriod plexus papilloma

•            2- Subarachnoid hemorrhage especially in the premature infant.           

•            3- Pneumococcal and tuberculous meningitis.

•            4- Intrauterine intracranial infections e.g. toxplasmosis, cytomegalovirus.

•            5- Leukemic infiltrations.

Clinical manifestations

Before closure of the fontanels:

•          Hydrocephalus may be evident at birth, but is usually manifested within the first few weeks of life.

•           Progressive increase of skull circumference.

•          Separation of sutures.

•           Fontanels: are widely opened, large tense anterior fontanel, persistence of posterior fontanel.

•           The scalp veins may be dilated in progressive cases.

•           The scalp skin is stretched, shiny and thin.

•           Macewen sign

•          A bruit is

•          Eyes: may show sun set appearance and optic atrophy in progressive cases.

•          Pyramidal lesion

•           Abnormal midline skin lesions, including tufts of hair may be present.

•           Mental retardation may occur very late as a result of extensive cerebral cortex atrophy.

In the older child: sutures are partially closed and head enlargement is less prominent. Headache is the prominent feature.

•          Irritability, lethargy, poor appetite, and vomiting are common to both age groups.

Diagnosis

History

Examination

Fundus examination

Transillumination of the skull

Plain x-ray of skull: shows large head, separated sutures, wide sella turcica.

Serology for TORCH

CT scan and MRI

Differential diagnosis

1. Megalencephaly
2. Subdural hematoma
3. 3- CNS degenerative and metabolic brain diseases.
4. 5- Brain tumors, cysts, or chronic abscess.
5. Treatment
6. Medical management acetazolamide and furosemide
7. shunts (v-p,v-a&v-p1)