Cerebrospinal Fluid Infections

Cerebrospinal fluid (CSF) shunting has been used for the treatment of hydrocephalus for over 40 years. Drainage of CSF into the peritoneal cavity via a ventriculoperitoneal (VP) shunt is the system used most frequently. Infection of CSF shunts is an important cause of morbidity. Although reported shunt infection rates range from 2 to 30 , the infection rate at most high volume institutions does not exceed 5 . Risk factors associated with the development of CSF shunt infection include shunts...

Urinary

The bladder should be catheterized for comfort, monitoring of urine output (to guide volume and blood-pressure management) and because of the common occurrence of acute urinary retention. Because of the risk of urinary tract infection or sepsis (often a lifelong concern for spinal-cord injured patients), the bladder catheter should be removed after any operative interventions in the first few days. If urinary retention is present, intermittent clean catheterization should be implemented....

Cerebral Blood Volume

Cerebral blood volume (total of 60 mL) is influenced by arterial inflow, venous drainage and cerebrovascular tone. Hypercarbia and hypoxemia result in pH-mediated cerebral vasodilation and must be avoided. Hyperventilation causes an alkalosis-mediated increase in cerebrovascular resistance and decrease in cerebral blood volume, thereby transiently decreasing ICP. This is particularly helpful for 'emergency' response to impending or ongoing cerebral herniation syndrome. Unfortunately,...

Extracranial Hematomas

Subgaleal hematomas fill the large potential space between the galea and periosteum. In neonates and infants, up to 250 cc of blood (a life-threatening hemorrhage) can accumulate in the subgaleal space, and are not restricted to the suture sites. Subgaleal hematoma commonly results from birth injury. Hematocrit should be followed closely and transfusions given if needed. Surgical evacuation is rarely indicated. Needle drainage should be avoided because of the potential for infection. Most...

Birth Injury

Brain injury at birth may result from a combination of mechanical forces imposed by the birth canal, obstetrical delivery, or forceps and suction devices, and temporary hypoxia. External signs of cranial birth trauma include caput succeda-neum, which consists of localized scalp edema from cranial molding in the birth canal, and subgaleal and subperiosteal hematomas (see above). Linear skull fractures from cranial molding or small depressed fractures caused by the delivering hand or instrument...

Acute Subdural Hematoma

The primary underlying brain injury associated with acute subdural hematoma is generally more severe than that seen with epidural hematoma, particularly in children. In children, subdural hematoma is often caused by local extension of hemor-rhagic intracerebral contusions into the subdural space. Onset of coma at the moment of injury is common. Localizing signs, which are less frequent than with epidural hematomas, depend variably on the location of the hematoma and any underlying cerebral...

Vascular Malformations

Central nervous system (CNS) vascular malformations are grouped into 4 categories arteriovenous malformations (AVM), cavernous angiomas (or, cavernous malformations), capillary telangiectasias and developmental venous anomalies (DVA). AVMs are the most important to recognize because of their propensity to hemorrhage. Children can also present with headaches, seizures, hydrocephalus or progressive neurological deficits. AVMs are congenital vascular malformations in which abnormally dilated...

Congenital Spinal Malformations

Split Cord Malformation

When imaging children with suspected congenital spinal malformations, one must be aware that multiple anomalies such as myelomeningocele, split-cord malformation, syringohydromyelia, and others may co-exist. Anomalies of the caudal spine must be considered in patients with urogenital or anorectal malformations. Sagittal and coronal imaging of the entire spine with MRI is recommended to identify the location of the conus medullaris (normal level T10 to L2), associated lipomas or syrinxes,...

Info

Pituitary Infundibulum

Supratentorial astrocytoma. Heterogeneous, predominantly T2-hyperintense mass centered in the deep gray nuclei. Small areas of enhancement. transaxial T1-WI with contrast, and T2-WI. Figure 25. Supratentorial astrocytoma. Heterogeneous, predominantly T2-hyperintense mass centered in the deep gray nuclei. Small areas of enhancement. transaxial T1-WI with contrast, and T2-WI. Figure 27. Large, left, hemispheric, irregular, heterogeneous, dense, enhancing PNET with cystic components and...

Window Level

Prior to interpreting any CT or MRI study, the contrast and brightness of the images must be adjusted properly. Contrast is represented by the window width or range of densities, which are displayed across the entire spectrum of gray shades i.e., gray scale . Pixels with a density value HU less than the lower window limit Table 3. Parameters of specific MRI sequences Indications Range TR ms TE ms Angle Hydrocephalus, posterior fossa pathology Coronal 3D spoiled gradient echo SPGR or MPRAGE...