Acute-onset cervical spine pain and neurologic deficit in a previously healthy young woman

A previously healthy 36-year-old teacher presented to her primary care physician with new acute-onset cervical spine pain to the right of midline, right shoulder pain, and distal extremity numbness and tingling. Clinical evaluation revealed no significant muscular weakness or loss of normal reflexes. Sensory symptoms were distributed in the fourth through sixth dermatomes. Laboratory evaluation included a serum chemistry panel and complete blood count, the results of which were normal. The patient's vital signs were normal, and there were no known or preexisting medical conditions. The onset of symptoms occurred after the patient lifted a heavy bag filled with schoolbooks. She underwent routine magnetic resonance (MR) imaging with intravenous contrast material (Figures 1 and 2).

Figure 1.

Sagittal MR images. (a) T1-weighted image demonstrates an extramedullary mass (arrows), which is isointense to the spinal cord. (b) T2-weighted image demonstrates mixed hyperintense and hypointense signal (arrows) relative to the spinal cord. (c) T1-weighted fat-saturated image after intravenous gadolinium demonstrates peripheral enhancement (arrows).

Figure 2.

Axial T1-weighted MR image after intravenous gadolinium demonstrates peripheral enhancement (arrows).

What is the most likely diagnosis based on the MR images and clinical history?What are reasonable differential diagnostic considerations?What is the most appropriate next step in the management of this case?

DIAGNOSIS: Spontaneous spinal epidural hematoma.

DISCUSSION

Spontaneous spinal epidural hematomas are rare, and relatively few cases have been described in the literature. Most reports are of a single case such as this one or are based on a small number of patients. The etiology is unknown, but it is generally accepted that most of these hematomas arise from rupture of the epidural venous plexus. Because the extensive epidural venous plexus is devoid of valves, increased pressure may lead to rupture of the veins and an epidural hematoma (1). The cause is often attributed to transient venous hypertension such as can occur with sudden Valsalva maneuvers. The patient in this case noted the onset of symptoms after lifting a heavy bag of schoolbooks. Other possible causes include anticoagulation or coagulopathy (both of which should be easily excluded with appropriate clinical correlation), associated disc extrusion (2), and an underlying vascular anomaly. Commonly, these hematomas are idiopathic (40% to 50% of cases in some series).

Presentation

Patients present most often with an acute onset of pain and radicular symptoms that mimic disc herniation. Depending on the severity of the bleed, there may be a rapid progression of neurologic impairment, and this determines the next step in management of the hematoma. No significant age, racial, or gender predominance is agreed upon in the literature, and there is disagreement as to the most common location in the spine (i.e., the cervical vs the thoracic spine). Spontaneous epidural hematomas in the lumbar spine have a strong association with disc herniation.

Imaging features

The MR imaging features in this case parallel those in several previously reported cases of acute spontaneous spinal epidural hematoma. T1-weighted images have been shown to be the most valuable in making the correct diagnosis in many of the previous reports. The initial images show an epidural mass that is isointense to the cord. This feature is one of the most important to recognize when considering this diagnosis and is seen most often when the patient is imaged within 48 hours of the onset of symptoms. In a few of the reported cases of spontaneous spinal epidural hematomas, the T1 isointensity relative to the cord persisted as late as 120 hours after symptom onset (3).

In posttraumatic spinal epidural hematomas, however, the blood seen on T1 images appears hyperintense relative to the cord because of the effects of methemoglobin. This feature is seen in the overwhelming majority of posttraumatic spinal epidural hematomas regardless of the time interval prior to imaging. It is possible that the difference in origin of the hematoma (spontaneous vs posttraumatic) accounts for the difference in the evolution of signal characteristics (3).

The evolution of the signal on the T1 images from initial isointensity to delayed hyperintensity on follow-up imaging is pathognomonic for spontaneous spinal epidural hematomas. Other key features seen in the teacher's case include hyper-intensity on T2-weighted images with small areas of internal hypointensity (deoxyhemoglobin) (Figure 3), and peripheral and internal linear enhancement after administration of intravenous gadolinium (Figure 4). The internal linear enhancement is attributed to the normally occurring septa within the lateral epidural fat or vessels in lateral extensions of epidural fat. Other reported enhancement patterns include central or nodular enhancement, which is believed to be secondary to extravasation of the contrast in actively leaking vessels (3).

Figure 3.

Axial T2 gradient echo MR images demonstrate predominantly hyperintense signal with some internal foci of hypointense signal.

Figure 4.

Axial T1-weighted MR image after intravenous gadolinium demonstrates some internal linear or septal enhancement (arrows).

Differential diagnosis

Differential diagnostic considerations are highly dependent on the appropriate correlation of the clinical picture and the MR imaging features. The primary considerations include epidural abscess and spinal epidural lymphoma. The clinical and laboratory findings should help exclude infection, and the imaging features are the most critical in excluding neoplasm. Angiographic evaluation to exclude underlying vascular malformation is not indicated unless imaging features such as abnormally enlarged vessels suggest this underlying disease (1).

Management

Appropriate management is dictated by the patient's symptoms and the imaging features. Early reports claimed that surgical evacuation of the hematoma was necessary to prevent damage to the spinal cord and/or involved spinal nerve roots. However, subsequent reports indicate that the course of the disease is relatively benign in many cases—especially in young patients—even with conservative treatment. Holtas et al concluded that age is probably one of the most important factors in determining outcome (1).

Although immediate surgical evacuation of the hematoma may be necessary in some instances, many cases have been conservatively managed with close neurologic monitoring and repeat MR imaging. In one prior report, the hematoma resolved within 1 week. The teacher in the current case showed nearly complete resolution on follow-up MR imaging and significant improvement in clinical symptoms at approximately 3 weeks. Neurologic status will likely continue to dictate management, as no consistent predictive MR imaging features have been reported that might help determine the patient's risk of permanent neurologic damage.