A 13-year-old boy presented with fever and neck pain and stiffness, which was initially misdiagnosed as culture-negative meningitis. Magnetic resonance images of the brain and cervical spine demonstrated what appeared to be an intradural extramedullary mass at the C1–3 level, resulting in moderate cord compression, and a Chiari Type I malformation. The patient underwent a suboccipital craniectomy and a C1–3 laminectomy with intradural exploration for excisional biopsy and resection. The lesion containing the parasite was extradural, extending laterally through the C2–3 foramina. Inflammatory tissue secondary to Onchocerca lupi infection was identified, and treatment with steroids and doxycycline was initiated. At the 6-month follow-up, the patient remained asymptomatic, with MR images demonstrating a significant reduction in lesional size. However, 10 weeks postoperatively, the infection recurred, necessitating a second operation. The patient was treated with an additional course of doxycycline and is currently maintained on ivermectin therapy. This is the second reported case of cervical O. lupi infection in a human. In the authors' experience, oral doxycycline alone was insufficient in controlling the disease, and the addition of ivermectin therapy was necessary.
Tsinsue Chen, Karam Moon, Daphne E. deMello, Iman Feiz-Erfan, Nicholas Theodore and Ratan D. Bhardwaj
Sam Safavi-Abbasi, Mehmet Senoglu, Nicholas Theodore, Ryan K. Workman, Alireza Gharabaghi, Iman Feiz-Erfan, Robert F. Spetzler and Volker K. H. Sonntag
The authors conducted a study to evaluate the clinical characteristics and surgical outcomes in patients with spinal schwannomas and without neurofibromatosis (NF).
The data obtained in 128 patients who underwent resection of spinal schwannomas were analyzed. All cases with neurofibromas and those with a known diagnosis of NF Type 1 or 2 were excluded. Karnofsky Performance Scale (KPS) scores were used to compare patient outcomes when examining the anatomical location and spinal level of the tumor. The neurological outcome was further assessed using the Medical Research Council (MRC) muscle testing scale.
Altogether, 131 schwannomas were treated in 128 patients (76 males and 52 females; mean age 47.7 years). The peak prevalence is seen between the 3rd and 6th decades. Pain was the most common presenting symptom. Gross-total resection was achieved in 127 (97.0%) of the 131 lesions. The nerve root had to be sacrificed in 34 cases and resulted in minor sensory deficits in 16 patients (12.5%) and slight motor weakness (MRC Grade 3/5) in 3 (2.3%). The KPS scores and MRC grades were significantly higher at the time of last follow-up in all patient groups (p = 0.001 and p = 0.005, respectively).
Spinal schwannomas may occur at any level of the spinal axis and are most commonly intradural. The most frequent clinical presentation is pain. Most spinal schwannomas in non-NF cases can be resected totally without or with minor postoperative deficits. Preoperative autonomic dysfunction does not improve significantly after surgical management.
Iman Feiz-Erfan, Eric M. Horn, Nicholas Theodore, Joseph M. Zabramski, Jeffrey D. Klopfenstein, Gregory P. Lekovic, Felipe C. Albuquerque, Shahram Partovi, Pamela W. Goslar and Scott R. Petersen
Skull base fractures are often associated with potentially devastating injuries to major neural arteries in the head and neck, but the incidence and pattern of this association are unknown.
Between April and September 2002, 1738 Level 1 trauma patients were admitted to St. Joseph's Hospital and Medical Center in Phoenix, Arizona. Among them, a skull base fracture was diagnosed in 78 patients following computed tomography (CT) scans. Seven patients had no neurovascular imaging performed and were excluded. Altogether, 71 patients who received a diagnosis of skull base fractures after CT and who also underwent a neurovascular imaging study were included (54 men and 17 women, mean age 29 years, range 1–83 years). Patients underwent CT angiography, magnetic resonance angiography, or digital subtraction angiography of the head and craniovertebral junction, or combinations thereof.
Nine neurovascular injuries were identified in six (8.5%) of the 71 patients. Fractures of the clivus were very likely to be associated with neurovascular injury (p < 0.001). A high risk of neurovascular injury showed a strong tendency to be associated with fractures of the sella turcica–sphenoid sinus complex (p = 0.07).
The risk of associated blunt neurovascular injury appears to be significant in Level 1 trauma patients in whom a diagnosis of skull base fracture has been made using CT. The incidence of neurovascular trauma is particularly high in patients with clival fractures. The authors recommend neurovascular imaging for Level 1 trauma patients with a high-risk fracture pattern of the central skull base to rule out cerebrovascular injuries.
Sam Safavi-Abbasi, Leonardo B. C. Brasiliense, Ryan K. Workman, Melanie C. Talley, Iman Feiz-Erfan, Nicholas Theodore, Robert F. Spetzler and Mark C. Preul
✓In 25 years, the Mongolian army of Genghis Khan conquered more of the known world than the Roman Empire accomplished in 400 years of conquest. The recent revised view is that Genghis Khan and his descendants brought about “pax Mongolica” by securing trade routes across Eurasia. After the initial shock of destruction by an unknown barbaric tribe, almost every country conquered by the Mongols was transformed by a rise in cultural communication, expanded trade, and advances in civilization. Medicine, including techniques related to surgery and neurological surgery, became one of the many areas of life and culture that the Mongolian Empire influenced.
Eric M. Horn, Iman Feiz-Erfan, Gregory P. Lekovic, Curtis A. Dickman, Volker K. H. Sonntag and Nicholas Theodore
Although rare, traumatic occipitoatlantal dislocation (OAD) injuries are associated with a high mortality rate. The authors evaluated the imaging and clinical factors that determined treatment and were predictive of outcomes, respectively, in survivors of this injury.
The medical records and imaging studies obtained in 33 patients with OAD were reviewed retrospectively. Clinical factors that predicted outcomes, especially neurological injury at presentation and imaging findings, were evaluated.
The most sensitive method for the diagnosis of OAD was the measurement of basion axial–basion dens interval on computed tomography (CT) scanning. Five patients with severe traumatic brain injuries (TBIs) were not treated and subsequently died. Of the 28 patients in whom treatment was performed, 23 underwent fusion and five were fitted with an external orthosis. Abnormal findings of the occipitoatlantal ligaments on magnetic resonance (MR) imaging, associated with no or questionable abnormalities on CT scanning, provided the rationale for nonoperative treatment. Of the 28 patients treated for their injuries, perioperative death occurred in five, three of whom had presented with severe neurological injuries. The mortality rate was highest in patients with a TBI at presentation. The mortality rate was lower in patients presenting with a spinal cord injury, but in this group there was a higher rate of persistent neurological deficits.
The spines in patients with CT-documented OAD are most likely unstable and need surgical fixation. In patients for whom CT findings are normal and MR imaging findings suggest marginal abnormalities, nonoperative treatment should be considered. The best predictors of outcome were severe brain or upper cervical injuries at initial presentation.
Report of three cases
Eric M. Horn, Ruth E. Bristol, Iman Feiz-Erfan, Elisa J. Beres, Nicholas C. Bambakidis and Nicholas Theodore
✓Pseudomeningoceles rarely develop after cervical trauma; in all reported cases the lesions have extended outside the spinal canal.
The authors report the first known cases of anterior cervical pseudomeningoceles contained entirely within the spinal canal and causing cord compression and neurological injury. The authors retrospectively reviewed the cases of three patients with traumatic cervical spine injuries and concomitant compressive anterior pseudomeningoceles. The lesion was recognized in the first case when the patient’s neurological status declined after he sustained a severe atlantoaxial injury; the pseudomeningocele was identified intraoperatively and decompressed. After the decompressive surgery, the patient’s severe tetraparesis partially resolved. In the other two patients diagnoses of similar pseudomeningoceles were established by magnetic resonance imaging. Both patients were treated conservatively, and their mild to moderate hemiparesis due to the pseudomeningocele-induced compression abated.
The high incidence of anterior cervical pseudomeningoceles seen at the authors’ institution within a relatively brief period suggests that this lesion is not rare. The authors believe that it is important to recognize the compressive nature of these lesions and their potential to cause devastating neurological injury.
Eric M. Horn, Nicholas Theodore, Iman Feiz-Erfan, Gregory P. Lekovic, Curtis A. Dickman and Volker K. H. Sonntag
The risk factors of halo fixation in elderly patients have never been analyzed. The authors therefore retrospectively reviewed data obtained in the treatment of such cases.
A discharge database was searched for patients 70 years of age or older who had undergone placement of a halo device. In a search of cases managed between April 1999 and February 2005, data pertaining to 53 patients (mean age 79.9 years [range 70–97 years]) met these criteria. Forty-one patients were treated for traumatic injuries. Ten patients had deficits ranging from radiculopathy to quadriparesis, and 43 had no neurological deficit. Adequate follow-up material was available in 42 patients (mean treatment duration 91 days). Halo immobilization was the only treatment in 21 patients, and adjunctive surgical fixation was undertaken in the other 21 patients. There were 31 complications in 22 patients: respiratory distress in four patients, dysphagia in six, and pin-related complications in 10. Eight patients died; in two of these cases, the cause of death was clearly unrelated to the halo brace. The other six patients died of respiratory failure and cardiovascular collapse (perioperative mortality rate 14%). Three patients who died had sustained acute trauma and three had undergone surgical stabilization.
External halo fixation can be used safely to treat cervical instability in elderly patients. The high complication rate in this population may reflect the significant incidence of underlying disease processes.
Cervical magnetic resonance imaging abnormalities not predictive of cervical spine instability in traumatically injured patients
Invited submission from the Joint Section Meeting on Disorders of the Spine and Peripheral Nerves, March 2004
Eric M. Horn, Gregory P. Lekovic, Iman Feiz-Erfan, Volker K. H. Sonntag and Nicholas Theodore
Object. Identifying instability of the cervical spine can be difficult in traumatically injured patients. The goal of this study was to determine whether cervical abnormalities demonstrated on magnetic resonance (MR) imaging are predictive of spinal instability.
Methods. Data in all patients admitted through the Level I trauma service at the authors' institution who had undergone cervical MR imaging were retrospectively reviewed. The reasons for MR imaging screening were neurological deficit, fracture, neck pain, and indeterminate clinical examination (for example, coma). Abnormal soft-tissue (prevertebral or paraspinal) findings on MR imaging were correlated with those revealed on computerized tomography (CT) scanning and plain and dynamic radiography to determine the presence/absence of cervical instability.
Of 6328 patients admitted through the trauma service, 314 underwent MR imaging of the cervical spine. Of 166 patients in whom CT scanning or radiography demonstrated normal findings, 70 had undergone MR imaging that revealed abnormal findings. Of these 70 patients, 23 underwent dynamic imaging, the findings of which were normal. In each case of cervical instability (65 patients) CT, radiographic, and MR imaging studies demonstrated abnormalities. Furthermore, there were 143 patients with abnormal CT or radiographic study findings, in 13 of whom MR imaging revealed normal findings. Six of the latter underwent dynamic testing, which demonstrated normal results.
Conclusions. Magnetic resonance imaging is sensitive to soft-tissue injuries of the cervical spine. When CT scanning and radiography detect no fractures or signs of instability, MR imaging does not help in determining cervical stability and may lead to unnecessary testing when not otherwise indicated.