7Skull and Scalp Lesions S : skinC : connective tissueA : [galea] aponeurosisL : loose connective tissueP : periosteumTraumatic LesionsA cephalohematoma is a traumatic subperiostealaccumulation of blood confined by the cranialsutures, as opposed to caput succedaneum, whichis a hemorrhage within the skin that crosses suturelines and is usually located at the vertex. Acephalohematoma also differs from a subgalealhematoma, which is a hemorrhage subjacent tothe aponeurosis covering the scalp beneath theoccipitofrontalis muscle and is also not confinedby the cranial sutures (Fig 23). The prevalence ofcephalohematomas is close to 1%–2% in spontaneousvaginal deliveries and 3%–4% in forcepsorvacuum-assisted deliveries (71). In cases ofprolonged resorption, cephalohematomas beginto calcify (72) and have a characteristic clinicaland radiologic appearance. They tend to increasein size after birth and manifest as a tense and firmmass, occasionally with an underlying skull fracture.Resolution usually occurs without treatmentby a few weeks to 3–4 months of age. Althoughcephalohematomas are not usually of clinical significance,they may present a challenge for theclinician because they occasionally become infected,requiring drainage and antibiotic therapy(72,73). At CT and MR imaging, acute cephalohematomasappear as crescent-shaped lesionsadjacent to the outer table of the skull (Fig 24).Chronic cephalohematomas may calcify and appearhyperattenuating at CT (Fig 25) (71,72).During the evolution of a cephalohematoma, amixed picture of erosive changes and periostealreaction can be worrisome, especially in the absenceof a good clinical history. At MR imaging,signal intensity typically follows that of subacutehemorrhage (ie, hyperintensity on T1- and T2-weighted images) but may vary depending on thestage of the hemorrhage.************************caput succedaneum : subcutaneous haematoma, most commonly secondary to vacuum assisted deliverysubgaleal haematoma : haematoma within the potential space between the galea aponeurosis and the skull periosteumcephalohaematoma : subperiosteal and therefore bound by the suture line
8Skull and Scalp Lesions Bilateral subgaleal hematoma
9Skull and Scalp Lesions Acute and chronic cephalohematoma; a crescent-shaped soft-tissue mass in the periosteum of the left parietal and a partially calcified mass in the periosteum of the left parietal bone. The mass originated from a cephalohematoma.Radiographics 2004; 24:1655–1674
16Epidural Hematoma (EDH) Classic arterial epidural hematoma; a lentiform, high attenuation collection adjacent to the right temporal lobe, caused by skull fracture with middle meningeal artery injury.Neurotherapeutics 2011; 8:
17Epidural Hematoma (EDH) Venous epidural hematoma; scalp soft tissue swelling with lentiform EDH and pneumocephalus indicated an associated skull fracture. CT venogram was obtained as the fracture line extended over the expected location of the right transverse sinus. The opacified transverse sinuses are patent with compression and displacement from the inner table by the EDH caused by injury to the transverse sinus.Neurotherapeutics 2011; 8:
35Subarachnoid Hemorrhage (SAH) Moderate to severe head traumaSuperficial sulciCSF cisterns
36Subarachnoid Hemorrhage (SAH) Common causesHead traumaIntracranial aneurysmPerimesencephalic hemorrhageLess frequent etiologiesArteriovenous malformationArterial dissectionExtension from intracerebral hemorrhagePerimesencephalic nonaneurysmal hemorrhage is AKA pretruncal nonaneurysmal hemorrhagePerimesencephalic nonaneurysmal hemorrhage is a benign form of subarachnoid hemorrhage (SAH).Angiographic changes of vasospasm are uncommon in patients with this type of hemorrhage (like because of the small amount of hemorrhage in this condition).
37Subarachnoid Hemorrhage (SAH) Pseudo-subarachnoid hemorrhageSevere diffuse brain edemaRelatively hyperdense vasculaturesA pseudo-SAH finding is a CT pseudolesion that shows SAH-like findings, in which the cisterns and cerebral sulci appear hyperattenuated relative to the brain parenchyma. This is a synergistic result of distention of the superficial vessels arising from elevated intracranial pressure and severe brain edema manifesting as hypoattenuated parenchymaA 34-year-old man with cardiac arrest. A, On the first day, no abnormal finding is seen. B, On the 8th day, the brain shows diffuse low attenuation with obliteration of cisterns-sulci and narrowed ventricles. High-attenuation areas along sylvian fissures and tentorium cerebelli. C, On the 129th day, brain edema becomes more severe with more prominent high attenuation areas.
38Subarachnoid Hemorrhage (SAH) Pseudo-empty delta sign: SSS thrombosisPosterior parafalcine/interhemispheric SDHSAH around sinusNote pseudo empty delta sign (arrow, A). Empty delta sign of cerebral venous thrombosis is applicable only on contrast-enhanced CTA pseudodelta sign can also be seen in patients with hyperattenuating acute subarachnoid hemorrhage around the sinus or subdural empyema or in patients with a posterior parafalcine interhemispheric hematoma. In these cases, administration of contrast material should opacify the sinus, obliterating the lucent center of the pseudodelta.AJR 2007; 189:
51A typical coup-contrecoup pattern of injury with an extracranial/skull injury at the point of direct impact and a more pronounced area of intracranial contusions at the directly opposite side of the head.
52Cortical Contusions Evolve with time Early 24-48 hours Ill-defined low densitySmall petechial hemorrhage24-48 hoursMore lesions20% delayed hemorrhage
53Cortical Contusions Blossoming of hemorrhagic contusions. (a)Multiple intracranial hemorrhages including a subtle left temporal hemorrhagic contusion, SDH along the right tentorium and SAH in the basilar cisterns and Sylvian fissure.(b) CT scan 6 hours later demonstrates expansion of the left temporal contusion.Neurotherapeutics 2011; 8:
54Intraventricular Hemorrhage (IVH) 1-5% close head injuryOther primary intraaxial lesionsEtiologyDisrupted subependymal veinsRuptured intracranial hemorrhageFocal choroid plexus hematomaIsolated IVH better outcome
589-year-old boy with motor vehicle accident. Initial CT showed subcortical hemorrhagic foci in left fronal lobe. Due to persistent reduced vigilance, MRI was orderedDiffuse axonal injuries in classic locations: Gray/white matter interface (predominantly in frontal and temporal lobes), the corpus callosum (especially the splenium) and the dorsolateral midbrain
61Diffuse Brain Swelling Diffuse cerebral swelling in this 32-year-old patient who sustained head trauma: diffuse sulcal effacement but relative preservation of gray-white differentiation.Neurotherapeutics 2011; 8:
62Diffuse Brain Swelling Twofold higher in childrenMore prone to dysautoregulationVasodilatation and hyperemiaCerebral swelling
64Cerebral Herniations Increased intracranial pressure Herniaed brain to another compartmentBony ridgesDural folds
65Cerebral Herniations Subfalcine Uncal Transtentorial Tonsillar Central DescendingAscendingTonsillarCentralTranscalvarialThis diagram illustrates the main types of brain herniation. In this case it is due to a mass lesion (a subdural hematoma) that is also causing secondary edema to the adjacent brain.Subfalcine Herniation: (1)The cingulate gyrus is pushed laterally away from the expanding mass and herniates beneath the falx cerebri.Transtentorial (Uncal) Herniation: (3) Due to the cerebral edema, the uncus of the temporal lobe (medial temporal lobe) herniates downward into the posterior fossa. Central herniation (2) occurs when there is downward pressure centrally and can result in bilateral uncal herniation.Tonsillar Herniation: (4)If there is also edema or hemorrhage causing swelling in the cerebellum, the tonsil (or tonsils) of the cerebellum herniates downward into the foramen magnum.
66Neurotherapeutics 2011; 8: 39-53. Subfalcine herniation (cingulate herniation): A unilateral supratentorial mass or hemorrhage results in a midline shift. If the pressure pushing the brain to one side is great enough, one of the hemispheres is pushed under the falx (subfalcine). This may compress the anterior cerebral artery. There is ipsilateral lateral ventricle compression and contralateral lateral ventricle dilation (due to obstruction of the foramen of Monroe).Large left holohemispheric and parafalcine subdural hematoma results in midline shift and subfalcine herniation.Neurotherapeutics 2011; 8:
67The left and center images show the suprasellar cistern The left and center images show the suprasellar cistern. Its anterior borders are formed by the frontal lobes (F). Its lateral borders are formed by the uncus (U) of the temporal lobes. The left image shows the 5-pointed star appearance of the suprasellar cistern where the posterior border is formed by the pons (Po). The black arrow points to the fourth ventricle. The center image shows a higher cut where the suprasellar cistern has a 6-pointed star appearance since the posterior border is formed by the cerebral peduncles (P) which have a central cleft. When ICP increases, the suprasellar cistern space is compressed. The space may still be visible; however, with severe intracranial hypertension, the cistern is obliterated due to encroachment of brain tissue that normally forms the borders of the suprasellar cistern. Depending on the cause of the intracranial hypertension, the suprasellar cistern may be totally obliterated in global or severe ICP increase. In focal lesions, brain tissue may encroach into only one part of the suprasellar cistern. In early unilateral uncal herniation, the uncus of the temporal lobe (lateral border of the suprasellar cistern) will protrude into the suprasellar cistern.The right image shows the quadrigeminal cistern (black arrow). Note the "baby's bottom" appearance of its anterior border. When ICP is increased, the quadrigeminal cistern space is compressed or obliterated.
69Subacute subdural hematoma producing extensive midline shift with subfalcine and right uncal herniation. There is trapping of the ventricles with acute ependymal cerebrospinal fluid seepage, predominantly in the left periatrial and occipital regions.
70Descending transtentorial herniation due to massive subdural hematoma Cerebral HerniationsDescending transtentorial herniation due to massive subdural hematomaradiologyimages.blogspot.com
76Neurotherapeutics 2011; 8: 39-53. Secondary HemorrhageLarge left holohemispheric and parafalcine subdural hematoma results in midline shift and uncal herniation. Downward brainstem herniation has led to classic Duret hemorrhage.Neurotherapeutics 2011; 8:
77Secondary HemorrhageExtensive cerebral edema with descending transtentorial herniation and a relatively large hemorrhage in brainstem. Because there is brain herniation, this hemorrhage is most likely Duret hemorrhage.
78Secondary HemorrhageThin chronic subdural hematoma with abnormal signal in the contralateral crus cerebri; Kernohan’s notch phenomenon.
81Traumatic Ischemia/Infarction Right-sided holohemispheric subdural hematoma results in subfalcine and uncal herniation with subsequently developed infarcts in ACA and PCA distributions with infarction of the posterior limb of the right internal capsule due to compression of theanterior choroidal artery with uncal herniation.Neurotherapeutics 2011; 8: