Why Do We Not Have a Drug to Treat Acute Spinal Cord Injury?

More than 100 years ago, Alfred Reginald Allen developed the weight-drop model of graded, reproducible contusion injury to the dorsal spinal cord. Allen also introduced the concept of secondary injury mechanisms, hypothesizing that hemorrhage and elevated intraspinal pressure contribute to the destruction of the spinal cord and functional deficits. Our understanding of the secondary injury cascade has advanced tremendously over the past 100 years, with numerous therapeutic targets identified. Yet we lack an effective drug treatment for acute spinal cord injury. Reasons for the failure to translate promising preclinical findings to successful clinical trials include concerns regarding the quality of preclinical studies, including possible bias and inappropriate statistical analysis; questions regarding the suitability of animal models; and the complexity of secondary mechanisms following spinal cord injury. Perhaps, however, we have overlooked the targets identified by Allen, namely the intraspinal hemorrhage and elevations in intraspinal pressure.

Superficial siderosis of the central nervous system associated with intraspinal hemorrhage from ventral thoracic epidural veins and a ventral spinal CSF leak: case report

In most patients with superficial siderosis of the CNS, the exact source of bleeding remains unknown because of a lack of objective surgical data. The authors herein describe the case of a 58-year-old man with superficial siderosis of the CNS. The patient also had spinal CSF leakage due to a spinal dural defect. Repair surgery for the dural defect was performed using posterior laminoplasty with a transdural approach without spinal fixation. During repair surgery, the bleeding source was found to be the epidural vein around the defect. The intraoperative and histological results of the present case suggest that epidural veins exposed to CSF represent a chronic bleeding source in patients with superficial siderosis of the CNS complicated by CSF leakage. Dural repair surgery may result in discontinuation of the CSF leaks, resolution of the epidural CSF collection, and cessation of chronic epidural bleeding.

Intraspinal hemorrhage in spontaneous intracranial hypotension: link to superficial siderosis? Report of 2 cases

Spontaneous intracranial hypotension due to a spinal CSF leak has become a well-recognized cause of headaches, but such spinal CSF leaks also are found in approximately half of patients with superficial siderosis of the CNS. It has been hypothesized that friable vessels at the site of the spinal CSF leak are the likely source of chronic bleeding in these patients, but such an intraspinal hemorrhage has never been visualized. The authors report on 2 patients with spontaneous intracranial hypotension and intraspinal hemorrhage, offering support for this hypothesis. A 33-year-old man and a 62-year-old woman with spontaneous intracranial hypotension were found to have a hemorrhage within the ventral spinal CSF collection and within the thecal sac, respectively. Treatment consisted of microsurgical repair of a ventral dural tear in the first patient and epidural blood patching in the second patient. The authors suggest that spontaneous intracranial hypotension should be included in the differential diagnosis of spontaneous intraspinal hemorrhage, and that the intraspinal hemorrhage can account for the finding of superficial siderosis when the CSF leak remains untreated.

Radiation-induced spinal cord hemorrhage (hematomyelia)

Intraspinal hemorrhage is very rare and intramedullary hemorrhage, also called <em>hematomyelia</em>, is the rarest form of intraspinal hemorrhage, usually related to trauma. Spinal vascular malformations such intradural arteriovenous malformations are the most common cause of atraumatic hematomyelia. Other considerations include warfarin or heparin anticoagulation, bleeding disorders, spinal cord tumors. Radiation-induced hematomyelia of the cord is exceedingly rare with only one case in literature to date. We report the case of an 8 year old girl with Ewing’s sarcoma of the thoracic vertebra, under radiation therapy, presenting with hematomyelia. We describe the clinical course, the findings on imaging studies and the available information in the literature. Recognition of the clinical pattern of spinal cord injury should lead clinicians to perform imaging studies to evaluate for compressive etiologies.

Drug interaction as cause of spontaneously resolving epidural spinal hematoma on warfarin therapy

ABSTRACTWe present a case of a 42-year-old male, an old case of deep vein thrombosis on warfarin and other drugs like quetiapine, aspirin, diclofenac sodium, fenofi brate, atorvastatin, propanolol and citalopram for concurrent illnesses, who presented with widespread mucocutaneous bleeding and epidural spinal hematoma. The epidural bleed presented clinically as a nontraumatic, rapidly improving myeloradiculopathy. Magnetic resonance imaging (MRI) of the spine revealed an epidural hematoma at D12-L1 level. The case was managed conservatively due lack of neurosurgical facilities. The patient gained full neurological recovery on conservative management alone. This case highlights the problem of drug interaction on warfarin therapy and also an unusual spontaneous recovery of spinal hematoma. Our case was anticoagulated in the recommended therapeutic INR range of 2.2 to 2.4. Most of the similar cases reported in literature were also anticoagulated in the therapeutic range. Thus intraspinal hemorrhage is a rare but dangerous complication of anticoagulant therapy. It must be suspected in any patient on anticoagulant agents who complains of local or referred spinal pain associated with neurological defi cits. Drug interactions with warfarin are common. High suspicion and immediate intervention are essential to prevent complications from intraspinal hemorrhage.