Spontaneous intracranial hemorrhage has also been documented in healthy term neonates (Rutherford, 2012; Shah, 2016). In a prospective MR imaging study, Whitby and coworkers (2004) found that 6 percent of those delivered spontaneously and 28 percent of those delivered by forceps had a subdural hemorrhage. None of these had clinical indings, and hematomas resolved by 4 weeks in all infants.
These blood collections accumulate outside the calvarium and are categorized as a cephalohematoma or subgaleal hemorrhage (Fig. 33-2). From its most superficial surface inward, the scalp is composed of skin, subcutaneous tissue, galea aponeurotica, subgaleal space, and calvarium periosteum. The galea aponeurotica is dense fibrous tissue, whereas the subgaleal space contains
TABLE 33-5. Major Types of Neonatal Intracranial Hemorrhage
Trauma-tentorial, falx, or venous (sinus) laceration Uncommon but potentially serious; symptom causing hematoma onset is variable depending on hematoma expansion, but usually <24 hours: irritability, lethargy, and brainstem compression
Possibly due to trauma or hypoxia-excludes SAH Common but almost always benign associated with subdural, intraventricular, intracerebral (AVM, aneurysm), or intracerebellar hemorrhage
Trauma and perhaps hypoxia-most cases in preterm Uncommon but serious infants Trauma and hypoxia (no discernible cause in Uncommon but serious; symptoms as for 25 percent)-hemorrhage usually from choroid plexus subdural hemorrhage Trauma with epidural or intracerebral hemorrhage Depends on cause Hemorrhagic infarction-embolism or thrombosis in
AVM = arteriovenous malformation; SAH = subarachnoid hemorrhage. Data from Volpe, 1995.
FIGURE 33-2 Schematic of extracranialolesions in the neonate that include caput succedaneum, subgaleal hemorrhage, and cephalohematoma.
loose, ibroareolar tissue. Traversing across the subgaleal space are large, valveless emissay veins, which connect the dural sinuses inside the skull with supericial scalp veins. Both the galea aponeurotica and subgaleal space span across the occipital, parietal, and frontal bones. In contrast, periosteum invests each individual skull bone and does not cross suture lines.
Cephalohematomas are cranial subperiosteal hematomas.
These develop from shearing forces during labor and delivery that lacerate the emissary or diploic veins. Fortunately, the densely adhered periosteum impedes rapid enlargement and limits inal hematoma size. Hemorrhage can be over one or both parietal bones, but palpable edges can be appreciated as the blood reaches the limits of the periosteum. These hematomas must be diferentiated from caput succedaneum, also shown in Figure 33-2. A cephalohematoma may not be apparent until hours after delivery, when bleeding suicient to raise the periosteum has occurred. After it is identiied, it often grows larger and persists for weeks or even months, and bleeding may be suicient to cause anemia as discussed on page 625. By contrast, with caput succedaneum, swelling of the scalp is from soft-tissue edema that overlies the periosteum. The caput is maximal at birth, rapidly grows smaller, and usually disappears within hours or a few days. Occasionally it becomes infected, and an abscess may form (Kersten, 2008).