Head trauma - interpreting CT scans

Transcription

1 Head trauma - interpreting CT scans Poster No.: C-2075 Congress: ECR 2014 Type: Educational Exhibit Authors: T. Rihtar; Zagreb/HR Keywords: Trauma, Hemorrhage, Edema, Diagnostic procedure, CT, Neuroradiology brain, Emergency DOI: /ecr2014/C-2075 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 70

2 Learning objectives The purpose of this educational exhibit is: to identify the radiological and pathological features of traumatic head injury to describe radiological spectrum of primary and secondary lesions to understand the importance of detection of treatable lesions Background Head trauma is medical emergency. The most common causes are traffic accidents, falls, firearm injuries, sport's and recreational activities. Head trauma is connected with a substantial risk of death, especially in the first posttraumatic hours, and sequels in form of cognitive, physical, emotional and social disorders. The role of neuroimaging is in early detection of traumatic brain injuries and prevention of secondary posttraumatic complications. CT scan is most often used in emergency units because it is quick, widely available and highly accurate in detection of acute intra-axial and extra-axial hemorrhage as well as skull and facial fractures. Another high value of CT is in possibility of following dynamics of posttraumatic lesions. Unenhanced CT is the examination technique of choice. The use of IV contrast media is restricted to cases in which a CT angiographic examination is needed when posttraumatic vascular pathology is suspected. Classification of head injuries: Open every injury with ruptured dura fatal injuries missile and penetrating injury Closed Primary - direct result of traumatizing force, non-preventable Page 2 of 70

3 Extra-axial lesions Fractures Epidural hematoma Subdural hematoma Subarachnoid hemorrhage Intraventricular hemorrhage Intra-axial lesions Diffuse axonal injury Cortical contusions Intracerebral hematoma Subcortical gray matter injury Vascular injuries Brainstem lesions Secondary - consequence of primary lesions, usually a result of mass effect or vascular compromise; often preventable Diffuse cerebral edema Cerebral herniation Hydrocephalus Ischemia/Infarction CSF leak Leptomeningeal cyst Encephalomalacia Findings and procedure details Missile and penetrating injury CT is essential for: assessment of missile tract type and extension of wound, bone fragments inside the brain intraventricular hemorrhage, ventricular laceration # serious vascular lesions # CT angiography is indicated #bad prognosis development of complications on follow-up scans # 7-14 days after trauma # hemorrhage, edema, abscess, necrosis, encephalomalacia, cerebritis, hydrocephalus Page 3 of 70

4 Fig. 1: CT shows gun shot wound with wide missile hemorrhagic tract at entering point (right frontotemporal) which gradually narrows to the exit point in left frontal bone; traumatic SAH at entering point as well as at the opposite side (contre coup) References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 4 of 70

5 Fig. 2: Missile injury, same patient: ventricular hemorrhage with midline shift; traumatic SAH at entering point as well as at the opposite side (contrecoup); subdural hematoma left frontal; plenty of tiny bone fragments inside the brain parenchyma at entering point; pneumocephalus References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 5 of 70

6 Fig. 3: Missile injury, same patient: the exit point of a bullet in left frontal bone; References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Fractures most common type of skull fracture is nondisplaced linear fracture of the calvarium # sometimes difficult to detect on CT scans when the fracture plane is parallel to the plane of section # isolated do not require treatment depressed fractures # associated with underlying contusions and contrecoup lesions # most are considered open and require debridement Page 6 of 70

7 compound fractures # surgical management is usually indicated # pneumocephalus may be seen temporal bone fractures # opacification of mastoid air cells, fluid in the middle ear cavity, pneumocephalus # longitudinal, transverse, complex facial fractures Fig. 4: Depressed parietal fracture with displacement of bone fragments by 1.3 cm; patient suffered from underlying contusion, traumatic SAH and subdural hematoma References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 7 of 70

8 Fig. 5: Comminuted fracture of all left maxillary sinus walls with displaced fragments and hematosinus; nasal bone fracture; swelling and hematoma of soft tissue References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Epidural hematoma blood collection between skull inner table and dura mater hyperdense biconvex extra-axial mass it can cross falx and tentorium, but doesn't cross sutures swirl sign - low density areas indicate actively bleeding hematoma with unretracted semiliquid clot # requires prompt surgical treatment Page 8 of 70

9 90% arterial (most common middle meningeal artery); underlying fracture in 85-95% 10% located in posterior fossa; usually venous origin; more common in children # symptoms are sometimes delayed because of slower expansion from lower venous pressures # increased mortality "vertex" epidural hematomas cross the superior sagittal sinus and displace it inferiorly # easily missed # coronal CT a "lucid" interval is seen in 50% of patients with epidural hematoma and precedes clinical deterioration acute epidural hematomas are most urgent of all cases of head trauma # require prompt treatment before irreversible parenchymal damage occurs, caused by compression of brain structures, especially the brainstem Page 9 of 70

10 Fig. 6: Right temporoparietal epidural hematoma, 1.3 cm wide References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 10 of 70

11 Fig. 7: Epidural hematoma: same patient, coronal plane; swirl sign References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Subdural hematoma Acute: homogenously hyperdense extra-axial fluid collection crescent-shaped, spreads diffusely over affected hemisphere Page 11 of 70

12 most common site is supratentorial convexity; it can extend along falx and tentorium it can cross sutures, but not dural attachments to bone compresses and displaces the underlying brain stretching and tearing of bridging cortical veins as they cross subdural space to drain into dural sinus Fig. 8: Acute subdural hematoma, 8 mm wide References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 12 of 70

13 Subacute: between few days and 3 weeks following the traumatic incident subdural hematoma becomes iso- to hypodense; may be the same density as the underlying cortex # easily missed on CT scan Signs to look for: disappearance of sharp gray - white junction border disappearance of the underlying cortical sulci displacement of the superficial brain parenchyma away from the bony inner table of the skull barely visible border between extra-axial collection and underlying brain in some cases fibrovascular proliferation forms a membrane # postcontrast enhancement recurrent, mixed-age hemorrhage is common; fluid - fluid level Page 13 of 70

14 Fig. 9: Residual (post evacuation) chronic left frontoparietal subdural hematoma; up to 1 cm wide, density a bit higher than CSF; internal septa and dural thickening; right frontal subdural hematoma, 8 mm wide, mixed density References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Chronic: over 3 week period, low density similar to CSF often septated, calcification in 1-2% enhancing surrounding membranes Page 14 of 70

15 progressive increase in density or size from 3 weeks to 3 months is likely from re-bleed of fragile neocapillaries in outer membrane Subarachnoid hemorrhage blood in subarachnoid spaces between pial and arachnoidal membranes hyperdense collections of blood in the sulci, fissures and cisternal spaces # hyperdense blood in interpeduncular cistern may be the only manifestation of subtle SAH rupture of small cortical vessels that traverse the subarachnoid space amount of SAH on initial CT correlates with delayed ischemia # poor prognosis usually associated with hemorrhagic parenchymal contusions requires supportive therapy Page 15 of 70

16 Fig. 10: Bilateral SAH References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Intraventricular hemorrhage rotational tearing of subependymal veins on ventricular surface, direct spread of intracerebral hematoma into ventricles typical sign: blood - CSF level in occipital horns hydrocephalus is a common sequel Page 16 of 70

17 Fig. 11: Spread of a huge intracerebral hematoma into third and lateral ventricles; blood-csf level References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 17 of 70

18 Fig. 12: Bilateral intraventricular hemorrhage, more prominent in the right lateral ventricle; ICP catheter inserted into the right lateral ventricle References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Diffuse axonal injury - DAI the most severe of all primary brain lesions axonal disruption from shearing forces of acceleration/deceleration clinically characterized by loss of consciousness immediately at the time of the trauma most common cause of posttraumatic vegetative state Page 18 of 70

19 CT is initially normal in 50% to 85% of patients; lesions become more prominent during the first 24 hours small (punctate to 15 mm), multiple lesions hypodense foci corresponding to edema at site of shearing injury; hyperdense foci of petechial hemorrhage; focal mass lesion with hemorrhagic/edema admixture common locations: cerebral hemispheres (frontotemporal) at gray-white junctions (50%), basal ganglia, splenium of corpus callosum, dorsal midbrain Fig. 13: Hemorrhagic axonal lesions - DAI Page 19 of 70

20 References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Cortical contusions commonly involve the cortex and are usually hemorrhagic, reflecting the rich vascularity of gray matter contusions that are not initially hemorrhagic tend to develop hemorrhage during the first 72 hours after the trauma # CT scan obtained 24 to 48 hours after injury usually shows contusions to be larger and more numerous blood mixed with brain tissue diffuse, often multiple characteristic locations: base of frontal lobes; poles, base and lateral surfaces of temporal lobes; dorsolateral quadrants of brainstem; at site of depressed skull fracture coup and contrecoup lesions Early CT: may be normal shows poorly defined hypodensity and swelling or patchy, ill-defined lowdensity lesion with small hyperdense foci of petechial hemorrhage h: multiple new hypodense lesions appear lesions often increase in size with surrounding edema # worsening mass effect delayed hyperdense hemorrhage develops in 20% of cases petechial hemorrhage may become hematomas Chronic contusion: iso- or hypodense brain parenchymal volume loss Page 20 of 70

21 Fig. 14: Bilateral frontal hemorrhagic cortical contusions with surrounding edema; right temporoparietal epidural hematoma References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Intracerebral hematoma usually caused by combined torsion and compression forces applied to the intraparenchymal vessels, causing them to rupture occurs acutely, typically due to primary vessel rupture Page 21 of 70

22 may appear sometime after the trauma, as a result of the confluence of multiple small laceration-contusion foci # CT scans performed in such cases immediately after the traumatic incident may be completely negative usually occurs in the same or nearly the same position of primary trauma well-circumscribed hyperdensity with or without a rim of perilesional edema frontal and temporal lobes up to 60% of cases are associated with epidural or subdural hematomas if the hematoma develops in a periventricular position it can rupture into the cerebral ventricles larger hematomas result in considerable mass effect # the added risk of downward transtentorial internal herniation Page 22 of 70

23 Fig. 15: Left temporal intracerebral hematoma References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Subcortical gray matter injury traumatic lesions of brainstem, basal ganglia, thalamus and regions around third ventricle 5-10% of primary traumatic brain injury caused by stretching and torsional forces that cause the rupture of small perforating vessels or by the direct impact of the dorsolateral surface of the brainstem against the tentorial incisura associated with DAI, cerebral contusion, extra-axial hemorrhage profound neurologic deficits, poor prognosis CT can be entirely negative or may show relatively minor findings # small hemorrhages in the areas of the brainstem surrounding the cerebral aqueduct and in the basal grey nuclei MR is superior to CT Page 23 of 70

24 Fig. 16: Hemorrhagic deep gray matter injury in left basal ganglia, 7 mm in diameter; intraventricular hemorrhage References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Vascular injuries can be asymptomatic, have a clinical onset sometime after the initial traumatic incident or be concealed by presence of other craniocerebral lesions # may be overlooked on routine imaging studies CT is useful technique for identifying patients with an increased risk of vascular lesions # patients with fractures at the base of the skull extending Page 24 of 70

25 into the bony internal carotid canal, sphenoid bone, petrous pyramid of the temporal bone and the basiocciput Internal carotid artery # the most frequently affected vessel in cranial trauma dissection due to the forced extension and torsion of the neck or due to the direct laceration of the arterial wall by a skull base fracture # trauma to the region directly adjacent to the anterior clinoid processes and the bony internal carotid canal pseudo-aneurysm # adventitia of the carotid artery wall can remain intact Arteriovenous fistula the most typical site is a fistula between the internal carotid artery siphon and the cavernous venous sinus # usually a consequence of fracture of central skull base suggestive indirect sign # enlarged, arterialized superior ophthalmic vein Page 25 of 70

26 Fig. 17: Fractures of all right orbital walls, both sphenoid sinuses, left sphenoid bone, right frontal and right temporal bone References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 26 of 70

27 Fig. 18: Same patient, two months later: hyperdensity on the left side of cavernous sinus; exophthalmos of the left eye References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 27 of 70

28 Fig. 19: Same patient, MRA: left carotid - cavernous fistula References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR lacerations, vessel occlusions # may or may not be associated with perivascular hematomas CT # fractures of the skull base; MR, MRA, DSA # greater diagnostic sensitivity Brainstem lesions Primary DAI: most common form dorsolateral aspect of the midbrain and upper pons location and lack of sufficient amounts of hemorrhage makes it difficult to diagnose on CT scans associated with lesions of frontal or temporal white matter and corpus callosum Contusions: caused by direct impact of the free margin of tentorium on the brainstem Page 28 of 70

29 Secondary infarction, hemorrhage, compression result of adjacent or systemic pathology ventral or ventrolateral aspect of the brainstem Duret hemorrhage - a characteristic lesion # midline hematoma in the tegmentum of the rostral pons and midbrain associated with descending transtentorial herniation neurologic injury caused by brainstem compression can be reversible in absence of intrinsic brainstem lesions Page 29 of 70

30 Fig. 20: Hemorrhagic traumatic lesions of pons and mesencephalon with compression on the fourth ventricle References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Diffuse cerebral edema in up to 10-20% of all severe head injuries usually evolves within h # in most serious cases it can develop in just a few hours severe clinical condition # fatal in approximately 50% of cases generalized obliteration of the cerebral cortical sulci and the intracranial subarachnoid spaces of the suprasellar and perimesencephalic cisterns (e.g., ambiens and quadrigeminal) cerebral ventricles appear thinned and compressed brain appears diffusely hypodense, with a loss of the distinction of the greywhite matter interface cerebellum is generally spared and can appear relatively hyperdense as compared to the cerebral parenchyma # white cerebellum sign in the later stages of evolution in severe cases diffuse cerebral edema is often accompanied by transtentorial internal cerebral herniation more common in children unilateral or bilateral Page 30 of 70

31 Fig. 21: Significant cerebral edema, especially right hemisphere, with compression on the ventricles and midline shift; traumatic SAH interhemispherally and in the right hemisphere sulci; right hemispheral lamelar subdural hematoma; significant swelling and hematoma of soft tissue left frontal References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Cerebral herniation Subfalcine herniation Page 31 of 70

32 most common form cingulate gyrus slips under free margin of falx cerebri compression of ipsilateral ventricle entrapment and enlargement of contralateral ventricle # obstruction at the level of foramen Monroi both anterior cerebral arteries may be displaced to the contralateral side # risk of ACA infarction in the distribution of callosomarginal branch Fig. 22: Right temporoparietal intracerebral hematoma with surrounding edema and compression on ventricular system; subfalcine herniation by 1.3 cm References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 32 of 70

33 Uncal herniation medial aspect of temporal lobe displaced medially over the free margin of tentorium focal effacement of the ambient cistern and the lateral aspect of the suprasellar cistern rarely, displacement of the brainstem causes compression of the contralateral cerebral peduncle against the tentorial margin # peduncular hemorrhage or infarction # Kernohan's notch Page 33 of 70

34 Fig. 23: Right temporoparietal intracerebral hematoma with significant uncal herniation of right temporal lobe and compression on brainstem and mesencephalon; References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Transtentorial herniation Descending brain herniates downward across the tentorium effacement of the suprasellar and perimesencephalic cisterns Ascending caused by large posterior fossa hematomas vermis and portions of cerebellar hemispheres herniate through the tentorial incisura loss of quadrigeminal cistern Tonsillar herniation herniation of the cerebellar tonsils downward through the foramen magnum External herniation swelling or mass effect causes the brain to herniate through a calvarial defect Hydrocephalus after subarachnoid or intraventricular hemorrhage # impaired CSF reabsorption at the level of arachnoid granulations or obstruction at the level of the aqueduct or fourth ventricle outflow foramina cerebral swelling, hematoma # compression of the aqueduct or fourth ventricle outflow foramina asymmetric lateral ventricles # compression of the foramen of Monro Page 34 of 70

35 Fig. 24: Right frontotemporoparietal craniotomy; hydrocephalus; significant gliotic and encephalomalacic lesions of right hemisphere; right parietal external herniation References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Ischemia/Infarction usually a consequence of cerebral herniation most common is posterior cerebral artery infarction from uncal herniation anterior cerebral artery infarction from subfalcine herniation posterior inferior communicating artery infarction from tonsillar herniation Page 35 of 70

36 posttraumatic ischemia can also result from raised intracranial pressure, embolization from a vascular dissection or secondary to globally reduced cerebral perfusion Fig. 25: Posttraumatic left frontotemporal ischemic lesion; uncal herniation References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR CSF leak mostly a consequence of fractures of the skull base Page 36 of 70

37 typically frontally positioned with CSF draining via a fistula into the ethmoid or the sphenoid paranasal sinus in 20% of cases complicated by meningitis # untreated can lead to the formation of cerebral abscess or extra-axial empyema clinical onset usually occurs within a week of the initial trauma, but can develop as late as several years after High resolution coronal acquisition CT # examination of choice to identify the associated skull base fracture the visualization of the fistula is often difficult or impossible to achieve # positive contrast CT or MR cisternography may be required Page 37 of 70

38 Fig. 26: CT cisternography: extralumination of contrast media into sphenoid sinus through bone defect in upper sinus wall - posttraumatic CSF leak; patient suffered from meningitis References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Fig. 27: CSF leak - transverse plane References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 38 of 70

39 Fig. 28: CSF leak - sagittal plane References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Leptomeningeal cyst "growing fracture" caused by traumatic tear in the dura # outpouching of arachnoid occurs at the site of a suture or skull fracture # leads to progressive, slow widening of skull defect appears as a lytic skull defect on CT or plain films which can enlarge over time Page 39 of 70

40 Encephalomalacia tissue loss with surrounding gliosis asymptomatic or a potential seizure focus CT: well-defined areas of low attenuation with volume loss, possibly a dilatation of adjacent ventricle characteristic locations are anteroinferior frontal and temporal lobes Fig. 29: Posttraumatic encephalomalacic lesions of both frontal lobes References: Clinical department for diagnostic and interventional radiology, University hospital "Sestre milosrdnice" - Zagreb/HR Page 40 of 70

41 Images for this section: Fig. 1: CT shows gun shot wound with wide missile hemorrhagic tract at entering point (right frontotemporal) which gradually narrows to the exit point in left frontal bone; traumatic SAH at entering point as well as at the opposite side (contre coup) Page 41 of 70

42 Fig. 2: Missile injury, same patient: ventricular hemorrhage with midline shift; traumatic SAH at entering point as well as at the opposite side (contrecoup); subdural hematoma left frontal; plenty of tiny bone fragments inside the brain parenchyma at entering point; pneumocephalus Page 42 of 70

43 Fig. 3: Missile injury, same patient: the exit point of a bullet in left frontal bone; Page 43 of 70

44 Fig. 4: Depressed parietal fracture with displacement of bone fragments by 1.3 cm; patient suffered from underlying contusion, traumatic SAH and subdural hematoma Page 44 of 70

45 Fig. 5: Comminuted fracture of all left maxillary sinus walls with displaced fragments and hematosinus; nasal bone fracture; swelling and hematoma of soft tissue Page 45 of 70

46 Fig. 6: Right temporoparietal epidural hematoma, 1.3 cm wide Page 46 of 70

47 Fig. 7: Epidural hematoma: same patient, coronal plane; swirl sign Page 47 of 70

48 Fig. 8: Acute subdural hematoma, 8 mm wide Page 48 of 70

49 Fig. 9: Residual (post evacuation) chronic left frontoparietal subdural hematoma; up to 1 cm wide, density a bit higher than CSF; internal septa and dural thickening; right frontal subdural hematoma, 8 mm wide, mixed density Page 49 of 70

50 Fig. 10: Bilateral SAH Page 50 of 70

51 Fig. 11: Spread of a huge intracerebral hematoma into third and lateral ventricles; bloodcsf level Page 51 of 70

52 Fig. 12: Bilateral intraventricular hemorrhage, more prominent in the right lateral ventricle; ICP catheter inserted into the right lateral ventricle Page 52 of 70

53 Fig. 13: Hemorrhagic axonal lesions - DAI Page 53 of 70

54 Fig. 14: Bilateral frontal hemorrhagic cortical contusions with surrounding edema; right temporoparietal epidural hematoma Page 54 of 70

55 Fig. 15: Left temporal intracerebral hematoma Page 55 of 70

56 Fig. 16: Hemorrhagic deep gray matter injury in left basal ganglia, 7 mm in diameter; intraventricular hemorrhage Page 56 of 70

57 Fig. 20: Hemorrhagic traumatic lesions of pons and mesencephalon with compression on the fourth ventricle Page 57 of 70

58 Fig. 21: Significant cerebral edema, especially right hemisphere, with compression on the ventricles and midline shift; traumatic SAH interhemispherally and in the right hemisphere sulci; right hemispheral lamelar subdural hematoma; significant swelling and hematoma of soft tissue left frontal Page 58 of 70

59 Fig. 22: Right temporoparietal intracerebral hematoma with surrounding edema and compression on ventricular system; subfalcine herniation by 1.3 cm Page 59 of 70

60 Fig. 23: Right temporoparietal intracerebral hematoma with significant uncal herniation of right temporal lobe and compression on brainstem and mesencephalon; Page 60 of 70

61 Fig. 24: Right frontotemporoparietal craniotomy; hydrocephalus; significant gliotic and encephalomalacic lesions of right hemisphere; right parietal external herniation Page 61 of 70

62 Fig. 25: Posttraumatic left frontotemporal ischemic lesion; uncal herniation Page 62 of 70

63 Fig. 26: CT cisternography: extralumination of contrast media into sphenoid sinus through bone defect in upper sinus wall - posttraumatic CSF leak; patient suffered from meningitis Page 63 of 70

64 Fig. 27: CSF leak - transverse plane Page 64 of 70

65 Fig. 28: CSF leak - sagittal plane Page 65 of 70

66 Fig. 29: Posttraumatic encephalomalacic lesions of both frontal lobes Page 66 of 70

67 Fig. 17: Fractures of all right orbital walls, both sphenoid sinuses, left sphenoid bone, right frontal and right temporal bone Page 67 of 70

68 Fig. 19: Same patient, MRA: left carotid - cavernous fistula Page 68 of 70

69 Fig. 18: Same patient, two months later: hyperdensity on the left side of cavernous sinus; exophthalmos of the left eye Page 69 of 70

70 Conclusion Imaging of acute head trauma is performed to detect treatable lesions before secondary neurologic damage occurs. CT imaging is the best choice because it is quick, widely available and highly accurate in the detection of acute intra-axial and extra-axial hemorrhage as well as skull and facial fractures. Traumatic head injury can be divided into primary and secondary forms. Primary lesions occur as a direct result of a blow to the head and secondary as a consequence of primary lesions, usually as a result of a mass effect or vascular compromise. Primary injuries have already occurred by the time patient arrives in the emergency department and secondary injuries are often preventable. Personal information Tamara Rihtar, MD; radiology resident, Clinical Department for Diagnostic and Interventional Radiology, Clinical Hospital Center "Sestre milosrdnice" Zagreb, Croatia References Bešenski N, Jankovi# S, Bu#a A: Klini#ka neuroradiologija mozga, Medicinska naklada Osborn Anne G et al.: Diagnostic imaging Brain, Amirsys Inc Castillo M: Neuroradiology Companion: Methods, Guidelines and Imaging Fundamentals, 3rd Edition, Lippincott Williams & Wilkins Brant W.E., Helms C.A.: Fundamentals of Diagnostic Radiology, Lippincott Williams & Wilkins Scarabino T, Salvolini U, Jinkins J.R.: Emergency Neuroradiology, Springer Berlin Heidelberg Page 70 of 70