Anterior spinal artery aneurysm presenting with spinal subarachnoid hemorrhage in a case of polyarteritis nodosa

Polyarteritis nodosa is characterized by presence of aneurysms in the renal, hepatic and mesenteric vasculature, and less often by vascular abnormalities in the intracranial compartment. Spinal subarachnoid hemorrhage is a rare phenomenon that can be associated with inflammatory vasculopathies such as polyarteritis nodosa, but the link between aneurysm formation and spinal subarachnoid hemorrhage in polyarteritis nodosa is unclear. We describe a case of a patient with polyarteritis nodosa and spinal subarachnoid hemorrhage following rupture of an aneurysm of the anterior spinal artery. Following operative washout and decompression of the subarachnoid hemorrhage, spinal digital subtraction angiography was performed and revealed intimal contour irregularities, stenotic changes, and multiple small aneurysms in renal, hepatic, and bronchial arteries and some proximal spinal arteries, and, most notably, a pseudoaneurysm of the anterior spinal artery supplied directly by the artery of Adamkiewicz. Polyarteritis nodosa was subsequently diagnosed in light of these findings. Though previous cases have noted spinal subarachnoid hemorrhage in of the context of polyarteritis nodosa, we found no previously documented case of a definitive aneurysm of the anterior spinal artery in a case of polyarteritis nodosa documented on angiography. This case highlights the potential importance of monitoring for aneurysms of the spinal vasculature in cases of polyarteritis nodosa and in screening for vasculitides in cases of spinal subarachnoid hemorrhage. Future studies are needed to describe patterns of the specific anatomic localization and incidence of spinal artery aneurysms in polyarteritis nodosa.     

MR imaging of acute spinal cord trauma

The thoracic spinal cords of five mongrel dogs were imaged with a 1.5 T MR scanner before and after trauma induced by a well-established method of spinal cord impaction that produces central cord hemorrhagic necrosis. The anesthetized dogs were studied acutely with a 5-in. circular surface coil, 12-cm field of view, sagittal and axial partial-saturation (TR = 600, TE = 25 msec) and spin-echo (TR = 2000, TE = 25-100 msec) techniques. One normal dog was used as a control. The cords were surgically removed and histologically examined. Direct correlation of the pathologic findings and imaging data showed that at the level of trauma there was obliteration of epidural fat and CSF spaces secondary to central cord hemorrhage and edema. The traumatized cords expanded to fill the bony canal, and there was loss of visualization of the internal anatomy of the cord (gray- and white-matter structures). We conclude that MR can accurately identify cord hemorrhage and edema within a few hours of spinal trauma.     

Imaging findings in spinal subarachnoid hemorrhage in patient with hemophilia A: an unusual cause for back pain

Back pain and presentation with spinal canal hemorrhage in hemophilia is not common; however, these are significant clinical issues and may lead to significant neurological issues and morbidity. We present an interesting case of severe back pain in a young patient with moderate hemophilia A. Imaging confirmed subarachnoid hemorrhage in the spinal canal without intracranial hemorrhage. To the best of our knowledge this is the first described case report of subarachnoid hemorrhage in hemophilia A in the English literature. We also describe the anatomy and imaging features of hemorrhage in the different spinal canal compartments, including the subarachnoid space. Spinal canal hemorrhage in hemophilia is an emergency and serious condition and must be diagnosed and treated promptly. It is important to be aware of the diagnostic features of the spinal canal hemorrhage and carefully assess the spinal canal in hemophiliacs on cross-sectional studies.     

The relationship between the functional abilities of patients with cervical spinal cord injury and the severity of damage revealed by MR imaging.

BACKGROUND AND PURPOSE: The appearance of the damaged spinal cord after injury correlates with initial neurologic deficit, as determined by the American Spinal Injury Association grade and manual muscle test score, as well as with recovery, as assessed by manual muscle test scores. The purpose of this study was to determine whether the presence of spinal cord hemorrhage and the size and location of spinal cord edema on MR images is predictive of functional recovery in survivors of cervical spinal cord injury (SCI). METHODS: The degree of damage to the cervical spinal cord was measured on the MR images of 49 patients who underwent imaging within 72 hours of sustaining SCI. The effects of hemorrhage and length/location of edema on changes in the value of the motor scale of the functional independence measure (FIM) were assessed on admission to and discharge from rehabilitation. RESULTS: Patients without spinal cord hemorrhage had significant improvement in self-care and mobility scores compared with patients with hemorrhage. There was no significant effect of spinal cord hemorrhage on changes in locomotion and sphincter control scores. The rostral limit of edema positively correlated with admission and discharge self-care scores and with admission mobility and locomotion scores. Edema length had a negative correlation with all FIM scales at admission and discharge. CONCLUSION: The imaging characteristics of cervical SCI (hemorrhage and edema) are related to levels of physical recovery as determined by the FIM scale. Imaging factors that correlate with poor functional recovery are hemorrhage, long segments of edema, and high cervical locations.     

Subarachnoid hemorrhage due to isolated spinal artery aneurysm in four patients

Spinal artery aneurysms are usually found with arteriovenous malformations or other entities that increase hemodynamic stress. Isolated spinal artery aneurysms are rare. Four patients who presented with the acute onset of lower back pain underwent MR imaging, which revealed spinal subarachnoid hemorrhage. In all patients, work-up yielded a diagnosis of isolated spinal aneurysm, and operative treatment was successful. In the appropriate clinical setting, spinal aneurysm should be considered as a possible cause of spinal subarachnoid hemorrhage.     

The early evolution of spinal cord lesions on MR imaging following traumatic spinal cord injury

BACKGROUND AND PURPOSE: How early spinal cord injury (SCI) lesions evolve in patients after injury is unknown. The purpose of this study was to characterize the early evolution of spinal cord edema and hemorrhage on MR imaging after acute traumatic SCI.MATERIALS AND METHODS: We performed a retrospective analysis of 48 patients with clinically complete cervical spine injury. Inclusion criteria were the clear documentation of the time of injury and MR imaging before surgical intervention within 72 hours of injury. The length of intramedullary spinal cord edema and hemorrhage was assessed. The correlation between time to imaging and lesion size was determined by multiple regression analysis. Short-interval follow-up MR imaging was also available for a few patients (n = 5), which allowed the direct visualization of changes in spinal cord edema.RESULTS: MR imaging demonstrated cord edema in 100% of patients and cord hemorrhage in 67% of patients. The mean longitudinal length of cord edema was 10.3 ± 4.0 U, and the mean length of cord hemorrhage was 2.6 ± 2.0 U. Increased time to MR imaging correlated to increased spinal cord edema length (P = .002), even after accounting for the influence of other variables. A difference in time to MR imaging of 1.2 days corresponded to an average increase in cord edema by 1 full vertebral level. Hemorrhage length was not affected by time to imaging (P = .825). A temporal increase in the length of spinal cord edema was confirmed in patients with short-interval follow-up MR imaging (P = .003).CONCLUSION: Spinal cord edema increases significantly during the early time period after injury, whereas intramedullary hemorrhage is comparatively static.

Acute traumatic spinal cord injury (SCI) is a devastating event with an incidence of approximately 11,000 injuries in the United States each year.¹ MR imaging is critical to the assessment of acute cervical SCI because it clearly depicts lesion location, extent, and severity. Spinal cord intramedullary edema and hemorrhage are readily appreciated^2,3 and, to some extent, correlate with the clinical neurologic deficit.^4–10 Prior studies have also revealed that both the presence of hemorrhage and increased hematoma length at MR imaging are associated with decreased motor recovery.^7–10Following the immediate structural and neurovascular insult, acute SCI sets into motion a cascade of secondary injuries.^11,12 Work in animals has shown that intramedullary spinal cord hemorrhage and edema are dynamic, whether assessed by histopathology or MR imaging.^13,14The extent to which cord lesions evolve in patients during the early phase of SCI (ie, the first hours and days postinjury) is unknown; therefore, given similar clinical deficits, it is unclear to what extent variability in lesion size reflects differences in time to imaging after trauma. Similarly, it is not clear whether lesion expansion when observed on a short-interval follow-up MR imaging study is an ominous sign or a usual feature in the natural evolution of SCI. This fundamental lack of knowledge is particularly limiting with regard to research aimed at preventing the secondary injury cascade. With an increasing number of therapies for SCI coming to trial, MR imaging can be expected to continue to be increasingly incorporated into research protocols for these agents. An understanding of the acute evolution of SCI lesions on MR imaging is essential if imaging is to be used effectively in these protocols. Additionally, the variability of SCI lesions with time, if demonstrated, would likely have a significant impact on efforts to correlate spinal cord lesion size and location to the neurologic level of injury, because prior studies have not systematically accounted for differences in time to imaging. Such variability currently limits the reliability of MR imaging to serve as an accurate predictor of the patient''s neurologic level and prognosis. This limitation is unfortunate in situations in which the MR imaging findings might be of particular utility, such as in the assessment of the obtunded patients or in patients not undergoing clinical evaluation at a specialized SCI center.To better understand the evolution of SCI lesions, we retrospectively studied how the time interval between trauma and MR imaging affects spinal cord lesion size in patients with similar neurologic deficits. We also directly measured cord edema changes in a small number of patients for whom short-term MR imaging follow-up was available.     

MR imaging of acute spinal cord injury: results of an experimental study in dogs

A weight-drop model was used to induce 16 acute lesions of varying severity in the spinal cords of eight mongrel dogs. The subsequent 3- to 7-hr postinjury MR images (0.5 T) were assessed. T1-weighted images contributed little information. Injection of gadolinium tetra-azacyclododecane tetraacetic acid did not result in significant enhancement. T2-weighted sequences offered precise detection and delineation of the lesions, displaying fusiform hyperintense signal abnormalities that corresponded to both edema and hemorrhage. In low-impact injuries, abnormalities were small and centrally located, sparing the periphery of the spinal cord. In these cases hemorrhage was minimal and limited to the center of the lesion. In severe-impact injuries, MR showed widespread longitudinal extension with involvement of the periphery of the spinal cord. In the most severe injuries, a central heterogeneous signal component was frequently observed opposite the site of impact because of important hemorrhage within the cord. Overall, hyperintense areas correlated closely with lesion severity, as demonstrated by pathologic findings. T2-weighted MR images obtained at 0.5 T were found to be reliable in the evaluation of acute spinal cord trauma.     

Extensive spinal epidural hematoma: a rare complication of aortic coarctation

Development of collateral circulation belongs among the typical signs of aortic coarctation. Cerebral or spinal artery aneurysm formation with increased risk of subarachnoid hemorrhage represent the most common neurovascular complication of this disease. We report a case of a 20-year-old sportsman who developed acute non-traumatic paraplegia as a result of extensive spinal epidural hemorrhage from collateral vessels accompanying aortic coarctation which was unrecognized up to that time. To the best of our knowledge, acute spinal epidural hematoma as a complication of aortic coarctation has not been previously reported.     

Automatic segmentation of rodent spinal cord diffusion MR images

MRI, is a key tool for noninvasive spinal cord lesion analysis; however, accurate, quantitative methods for this analysis are lacking. A new, multistep, multidimensional approach, utilizing the classification expectation maximization algorithm, is proposed for MRI segmentation of spinal cord tissues. Diffusion tensor imaging is used to generate multiple images of each spinal slice, with different diffusion direction weightings. The maximum likelihood tissue classifications are then jointly estimated to produce a binary classification image, corresponding to voxels containing either spinal cord or background. Edge detection is employed to find a nonparametric curve encapsulating the entire spinal cord. The algorithm is evaluated using data from in vivo diffusion tensor imaging of control and injured mouse spinal cords. The algorithm is shown to remain accurate for whole spinal cord, white matter, and hemorrhage segmentation in the presence of significant injury. The results of the method are shown to be at least on par with expert manual segmentation. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.     

Diagnostic imaging potentialities of nuclear resonance tomography. Changes in vertebrae, ligaments and intervertebral disks in comparison with computed tomography

This is a study of 49 patients with lesions of the spine excluding primary tumors of the spinal cord. All patients were examined by computed tomography and magnetic resonance imaging. Comparing both methods we observed slight diagnostic advantages for magnetic resonance imaging in inflammatory and neoplastic disease. Especially for evaluation of the spinal cord and subarachnoid space MR-imaging is far superior to computed tomography.     

Absent cord sign in acute spinal trauma

Review of magnetic resonance imaging (MRI) findings in 100 patients suffering acute spinal trauma from 1985 to 1987 revealed four patients who had suffered thoracic spine fractures and acute subarachnoid hematomas. The spinal cord was not demonstrated on the T1-weighted sagittal MRI due to the similarities in signal intensity between the spinal cord and acute hemorrhage. Nonvisualization of the thoracic cord should not be presumed to be artifactual until subarachnoid hematoma is excluded.     

Solitary spinal artery aneurysms as a rare source of spinal subarachnoid hemorrhage: potential etiology and treatment strategy

Solitary aneurysms of spinal arteries lacking associated vascular malformations are rare. We report three patients with spinal subarachnoid hemorrhage (SAH) due to rupture of such aneurysms, which regressed spontaneously, as confirmed on conventional angiography. One patient had spinal SAH with presumed spontaneous dissection of a segmental artery. In the other two, SAH resulted from ruptured fusiform aneurysms of the artery of Adamkiewicz immediately proximal to the anterior spinal artery. Solitary aneurysms of the spinal arteries appear to be etiopathologic entities completely different from intracranial aneurysms. Spontaneous occlusion seems to be common, justifying a wait-and-see strategy rather than urgent treatment.     

Remote cerebellar hemorrhage after lumbar spinal surgery

Background

Postoperative remote cerebellar hemorrhage (RCH) as a complication of lumbar spinal surgery is an increasingly recognized clinical entity. The aim of this study was to determine the incidence of RCH after lumbar spinal surgery and to describe diagnostic imaging findings of RCH.

Methods

Between October 1996 and March 2007, 2444 patients who had undergone lumbar spinal surgery were included in the study. Thirty-seven of 2444 patients were scanned by CT or MRI due to neurologic symptoms within the first 7 days of postoperative period. The data of all the patients were studied with regard to the following variables: incidence of RCH after lumbar spinal surgery, gender and age, coagulation parameters, history of previous arterial hypertension, and position of lumbar spinal surgery.

Results

The retrospective study led to the identification of two patients who had RCH after lumbar spinal surgery. Of 37 patients who had neurologic symptoms, 29 patients were women and 8 patients were men. CT and MRI showed subarachnoid hemorrhage in the folia of bilateral cerebellar hemispheres in both patients with RCH. The incidence of RCH was 0.08% among patients who underwent lumbar spinal surgery.

Conclusion

RCH is a rare complication of lumbar spinal surgery, self-limiting phenomenon that should not be mistaken for more ominous pathologic findings such as hemorrhagic infarction. This type of bleeding is thought to occur secondary to venous infarction, but the exact pathogenetic mechanism is unknown. CT or MRI allowed immediate diagnosis of this complication and guided conservative management.     

核磁共振成像在脊髓损伤中的应用

核磁共振成像（ＭＲＩ）在脊髓损伤的诊台中具有重要的意义：ＭＲＩ上表现为出血者较单纯水肿者的病情重,预后差,且均与病灶的大小有关;有脊髓压迫者的病情重,预后差;ＭＲＩ对指导创伤性脊髓空洞症的治疗也有重要的价值。     

脊柱脊髓开放性损伤15例

目的 探讨脊柱脊髓开放性损伤的临床特点、诊断和治疗.方法 15例脊柱脊髓开放损伤患者,男14例,女1例;年龄15～46岁,平均23岁.损伤部位:颈脊髓2例,胸脊髓11例,腰脊髓2例.刀刺伤12例,火器伤2例,木棍刺伤1例.术前按美国脊髓损伤学会(ASIA)分级:A级1例,B级2例,C级7例,D级4例,E级1例.4例伤口内有异物存留,合并棘突骨折3例,椎板骨折8例,椎体骨折5例.15例均行急诊手术清创,根据损伤具体情况,行椎管探查、血肿清除、异物取出术.结果 术后发生脑脊液漏2例;1例术后伤口感染,无脊髓感染;5例术后神经功有不同程度的恢复.术后ASIA分级:A级1例,B级0例,C级3例,D级10例,E级1例.结论 脊柱脊髓开放性损伤需在充分地术前准备下急诊手术治疗,术前应了解是否有异物存留,手术探查减压,有利于脊髓功能的恢复,减少污染、出血等并发症的发生.     

脊柱脊髓开放性损伤15例

目的 探讨脊柱脊髓开放性损伤的临床特点、诊断和治疗.方法 15例脊柱脊髓开放损伤患者,男14例,女1例;年龄15～46岁,平均23岁.损伤部位:颈脊髓2例,胸脊髓11例,腰脊髓2例.刀刺伤12例,火器伤2例,木棍刺伤1例.术前按美国脊髓损伤学会(ASIA)分级:A级1例,B级2例,C级7例,D级4例,E级1例.4例伤口内有异物存留,合并棘突骨折3例,椎板骨折8例,椎体骨折5例.15例均行急诊手术清创,根据损伤具体情况,行椎管探查、血肿清除、异物取出术.结果 术后发生脑脊液漏2例;1例术后伤口感染,无脊髓感染;5例术后神经功有不同程度的恢复.术后ASIA分级:A级1例,B级0例,C级3例,D级10例,E级1例.结论 脊柱脊髓开放性损伤需在充分地术前准备下急诊手术治疗,术前应了解是否有异物存留,手术探查减压,有利于脊髓功能的恢复,减少污染、出血等并发症的发生.     

脊柱脊髓开放性损伤15例

目的 探讨脊柱脊髓开放性损伤的临床特点、诊断和治疗.方法 15例脊柱脊髓开放损伤患者,男14例,女1例;年龄15～46岁,平均23岁.损伤部位:颈脊髓2例,胸脊髓11例,腰脊髓2例.刀刺伤12例,火器伤2例,木棍刺伤1例.术前按美国脊髓损伤学会(ASIA)分级:A级1例,B级2例,C级7例,D级4例,E级1例.4例伤口内有异物存留,合并棘突骨折3例,椎板骨折8例,椎体骨折5例.15例均行急诊手术清创,根据损伤具体情况,行椎管探查、血肿清除、异物取出术.结果 术后发生脑脊液漏2例;1例术后伤口感染,无脊髓感染;5例术后神经功有不同程度的恢复.术后ASIA分级:A级1例,B级0例,C级3例,D级10例,E级1例.结论 脊柱脊髓开放性损伤需在充分地术前准备下急诊手术治疗,术前应了解是否有异物存留,手术探查减压,有利于脊髓功能的恢复,减少污染、出血等并发症的发生.     

Surgical neuroangiography of the spine and spinal cord

The SCAVMs are high-flow lesions that present at a younger age, during the second or third decades of life. The most common presenting symptoms are subarachnoid hemorrhage and hematomyelia. Endovascular treatment of these lesions has become an important adjunct to surgical management. Complete occlusion is possible by superselective catheterizations and injection of a liquid embolic material. The SDAVFs are slow-flow AV shunting at the dura, which causes progressive neurologic deficit in older age--the fifth or sixth decades of life. Embolization is now the primary mode of treatment. Preoperative embolization of the hypervascular tumors of the spine and spinal cord has become a necessity to reduce bleeding during surgery, and it even reduces the size of the tumor and relieves spinal block. Thorough knowledge of vascular anatomy and better understanding of hemodynamics of these lesions are essential to perform proper and safe embolization.     

MR imaging of traumatic spinal injuries

Plain films form the initial evaluation in all cases of spinal trauma. In cases of indeterminate or incomplete plain radiographs, further evaluation should be performed by multiplanar computed tomography (CT) and/or magnetic resonance imaging (MRI). Rapid triage is important to distinguish surgical and nonsurgical cases, as this has implications in terms of relief of cord compression and long-term prognosis. CT is unparalleled in its capacity to demonstrate bony abnormalities. MRI is the modality of choice in the evaluation of soft tissue injuries, in particular where there is a suspicion of ligamentous or intervertebral disc injury and spinal cord injury. MRI has the ability to distinguish between spinal cord edema and hemorrhage, which has important prognostic significance.     

Evidence-based approach to use of MR imaging in acute spinal trauma

MR imaging directly shows integrity of spinal cord, and provides sensitive assessments of structurally important soft tissue investments of the vertebral column. High-resolution images should be acquired in at least two planes, with T1 and fluid sensitive sequences. In the acute and subacute settings, MR may be used to assess integrity of intervertebral discs prior to closed reduction of inter-facetal dislocations, to discriminate between neurological deficits due to intra-substance hemorrhage or edema, and to determine the status of spinal ligaments as an adjunct to 'clearing' the spine.