CT Diagnosis of Spinal Epidural Hematoma

190 CT Diagnosis of Spinal Epidural Hematoma M. Judith Donovan Post, 1 David S. Seminer,2 and Robert M. Quencer 1 An acute spinal epidural hematoma is a neurosurgical sudden fl accid paraplegia of the lower extremities 18 hr later, with emergency. If a prompt diagnosis is not made and de sensory level to L 1. Partial thromboplastin time was more th an twice compression not undertaken shortly after the onset of symp th e norm, greater th an 100 sec. Although th e heparin infusion was toms, neurologic deficits are usually irreversible and death stopped and Protamine and Decadron were admini stered, th e sen sory level progressed to T 4 within the next few hours. often ensues [1 -6]. Although early recognition of this con A plain hi gh-resolution GT scan of th e th oracolumbar spine with dition is possible with high-resolution computed tomography 1.0-cm-thick sections on the GE GT / T 8800 scann er revealed an (CT) because the hematoma may be directly visuali zed, the acute epidural hematoma at several levels of the upper lumbar and use of high-resolution CT in this condition has not been mid and lower thoracic spine (figs. 1 A and 1 B); subarachnoid blood emphasized in the literature. We report a case of spinal extended to the T5 level (fig . 1 G). To better diagnose th e exact epidural hematoma and subarachnoid blood th at developed extent of the hematoma and to show th e position of th e spinal cord after traumatic lumbar puncture and anticoagulation. We before neurosurgical interve ntion, myelog raph y was performed. A establi shed the diagnosis with plain and metrizamide CT sin gle midline lumbar puncture at L5-S 1 under fluoroscopic control scans. This diagnosis was confirmed at autopsy. revealed grossly bloody subarachnoid fluid . Metrizamide (5 ml at a concentrati on of 170 mg / ml) was introduced through a 20 gauge spinal needle. A partial posterior extradural block was encountered Case Report at the L2-L3 level. Howeve r, the metrizamide passed into the th oracic canal in too small a volume to permit delineation of the A 76-year-old man with a history of hypertension was admitted upper level of the epidural hematoma on routine radiographs. Sub with a complaint of visual loss. He had been well until 5 days before seq uent metrizamide GT with 1-cm-thick sections confirmed an admission when he ex peri enced th e sudden onset of blurred vision epidural hematoma (fig. 1 D) and showed that it extended continu in both eyes. His vision became progressively worse over th e next ously from L2-L3 to T5. few days until he could perceive onl y light. On th e day of ad mission Despite recommendation for immediate surgery, the patient and he had a sudden onset of li ghtheadedness with staggerin g gait and hi s family refused, and 18 hr later the patient died. Autopsy revealed dysarthria. He had no diplopia, ve rtigo, dysphagia, weakness, a diffuse extensive epidural hematoma from (at least) L 1 to G7 . numbness, or headache. The positive findings on physical exami There was recent occlusion of the basilar artery, an old infarct of nation inclu ded a blood pressure of 160/ 90 mm Hg, impairmen t of the right parietal lobe, and severe atherosclerosis of the cerebral memory, visual acuity of 20/ 100 bilaterall y with concentricall y arteries. constricted visual fi elds, and mild left-sided weakness and hyper reflexia. The impression was right hemispheric stroke and vertebral basil ar in sufficiency. Pertinent admission laboratory tests included Discussion a prothrombin time and a partial thromboplastin time th at were normal, 9.8 sec (with a 10.8 sec control) and 37 sec, respectively. Spinal epidural hematomas develop from trauma, coagu GT scan of the brain showed a non hemorrhagic old infarct in th e lopathies, pregnancy, infection, neoplasm, and rupture of distribution of the right middle cerebral artery. Lumbar puncture arteriovenous malformations, venous angiomas, or epidural was attempted several times at different levels in the upper lumbar varicose veins [1 ,2,7-9]. Th ey can be spontaneous or can spine but was unsuccessful. On several passes, blood was ob follow minor activities such as coughing, sneezing, or twist tained. Because of the patient's symptoms of ischemia to the ing [2,6,8,9]. When iatrogenic, they can be complications posterior circulation and the absence of hemorrhage on GT scan, of lumbar puncture, epidural spinal anesthesia, spinal sur anticoagulation therapy with heparin was initiated 3 hr after lumbar puncture. gery, or anticoagulant therapy [2,6, 7-12]. Subarachnoid About 12 hr after the beginning of heparin therapy, th e patient bleeding and/ or subdural hematoma can also be caused by developed a substernal bandli ke pressure sensation in his chest. a spinal tap alone or in conjunction with anticoagulant There were no electrocardiographic (EGG) changes. He developed therapy or thrombocytopenia [6, 10-14]. One-third of the Received August 3 , 1981; accepted September 30, 1981. ' Department of Radiology, R-1 30, Neuroradiology Section, University of Miami School of Medicin e, Miami, FL 33101 . Address reprin t requests to M. J . D. Post, P.O. Box 016960, ' Department of Neurology, University of Miami School of Medicin e, Miami, FL 33101. AJNR 3:190-192, March/ April 19820195-6108 / 82/ 0302-01 90 $00.00 © American Roentgen Ray Society AJNR:3, March i April 1982 CT OF SPINAL EPIDURAL HEMATOMA 191 Fig . 1 .-A and B, Pl ain high-resolution CT scans. Acute spinal epidural subarachnoid sac (1 34 H) which su rrounds more lucent thoracic spinal cord hematoma (arrows) in thoracic spine diagnosed by sharply demarcated focal above level of well defined hematoma. D, Metrizamide high resolution CT areas of increased density of 104-110 Hounsfield units (H). Approximation scan. Thoracic hematoma as radiolucent posterior extradural filling defect of hematoma to inner margin of osseous spine. C, Pl ain high resolution CT (arrow) displaces metrizamide-filled subarachnoid sac and spinal cord ante scan. Subarachnoid blood (arrow) evident by diHuse area of hyperdensi ty in riorly. reported cases of spinal epidural hematoma have developed within this epidural venous system, the epidural veins are after anticoagulation with either heparin or dicumarol [6, not protected again st changes in pressure in neighboring 12]. Predisposing factors to spinal hemorrhage have in venous structures [2]. Therefore, rises in intraabdomin al or cluded hypertension, old age, clotting studies greater than intrathoracic pressure are readily transmitted to the epidural two times normal, and antecedent lumbar punctures [5, 7]. venous plexus and can result in rupture of these frag il e The risk of bleeding is increased if the lumbar puncture is structures. When bleeding occurs, it usually is more exten traumatic and if anticoagulation is initiated within 1 hr after sive posteriorly because the epidural space is the largest lumbar puncture [10, 14]. Because of this danger, it has there [2]. been suggested recently that spinal taps might be aban A spinal epidural hematoma typically develops with dra doned as a method for excluding subarachnoid bleeding matic suddenness: there is an abrupt onset of severe back before anticoagulation [1 0]. Different investigators have pro or neck pain with radiation into the chest, legs, or arms [1, posed that CT could be used instead to detect any intracra 6, 11]. Extremity weakness and urinary retention soon de nial hemorrhage that might mitigate against the use of velop [2, 5, 8]. Within minutes, hours, or days, the paresis anticoagulants for ischemic vascular disease, even though may progress to paraplegia or quadriplegia [2 , 4, 6, 9, 11). it is known that CT may fai l to detect small amounts of blood Occasionally, the symptoms and signs of acute spin al cord within the subarachnoid space [10]. or cauda equina compression may be preceded by episodic Spinal epidural hematomas do not spare any age group bouts of pain and weakness [4]. This may be due to repeated and have been reported in patients aged 14 months to 79 small hemorrhages in preexisting vascular anomali es. In a years [2, 8]. They are commonly seen, however, in elderly small percentage of patients, the onset of symptoms may people with hypertension and arteriosclerosis and are un be insidious, resulting in discovery of a chronic spinal epi common in children [1 , 2]. They have no gender predilection dural hematoma when a diagnostic evaluation is finally un [8]. Any spinal level can be involved, although the thoracic dertaken [8]. Although spontaneous remissions have been spine is most commonly affected [2]. They may be localized reported, the prognosis usually is poor unless surgery is to one spinal segment, but extension to three or more spinal undertaken at the first signs of spinal cord or cauda equina levels is common. The entire spinal canal can be affected compression [4, 6]. too [2, 8]. In the past, myelography has been advocated as the The anatomy of the spinal epidural space seems to be a procedure of choice for diagnosing spinal epidural hema predisposing factor to the formation and extension of epi toma [2, 4, 8]. This study has usually revealed partial or total dural hematomas. The epidural space is composed of loose extradural blocks and less commonly, nonobstructing ex areolar tissue and an extensive network of epidural veins tradural defects [1 -4, 7-9]. Dorsal impingement has pre [2, 12]. These veins are less well protected than the intra dominated over ventral and / or lateral extradural encroach cranial epidural veins because there is a larger space that ment [2]. separates them from the adjacent bone [12].

Load more