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Udaya K. Kakarla, M. Yashar S. Kalani, Giriraj K. Sharma, Volker K. H. Sonntag and Nicholas Theodore

Object

Coccidioides immitis is a dimorphous fungus endemic in the southwestern US and northern Mexico. While its primary presentation is pulmonary, it can have devastating neurological sequelae.

Methods

The authors provide a retrospective review with long-term follow-up between 1986 and 2008 at a single institution.

Results

The authors identified 27 patients between 13 and 81 years old (mean 41.4 years) with spinal coccidioides who were treated surgically at the Barrow Neurological Institute between 1986 and 2008. There were 24 males (89%) and 3 females (11%). Eleven patients (41%) had cervical spine involvement, 15 (56%) had thoracic involvement, 7 (26%) had lumbar involvement, and 2 (7%) had sacral involvement. All 27 patients presented with localized or radiating pain. Nine patients (33%) had myelopathic symptoms at presentation, 5 (19%) had radiculopathy, 4 (15%) had fever, and 12 (44%) had progressive kyphosis. The disease was most frequently seen among African American patients (14 patients [52%]), followed by Caucasians (5 patients [19%]), Asians (3 patients [11%]), and Hispanics (3 patients [11%]). Ten patients (37%) required multiple operations at the same level. Follow-up was available in 19 patients (70%) (mean 9.8 months, range 1–39 months). Sixteen (84%) of these 19 patients improved from their preoperative baseline states, 1 (5%) was stable on examination, 1 patient's condition (5%) deteriorated compared with the preoperative examination, and 1 patient (5%) died in the postoperative period.

Conclusions

Although spinal involvement of coccidioidomycosis is relatively uncommon, a high index of suspicion and aggressive therapy are warranted to prevent devastating neurological injury, and lifelong antifungal therapy is often warranted.

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Francisco A. Ponce, Brendan D. Killory, Scott D. Wait, Nicholas Theodore and Curtis A. Dickman

Object

Thoracoscopy may be used in place of thoracotomy to resect intrathoracic neoplasms such as paraspinal neurogenic tumors. Although these tumors are rare, they account for the majority of tumors arising in the posterior mediastinum.

Methods

A database was maintained of all patients undergoing thoracoscopic surgery for tumors. The authors analyzed the presenting symptoms, pathological diagnoses, and outcomes of 26 patients (7 males and 19 females, mean age 37.2 years) who were treated for intrathoracic tumors via thoracoscopy between January 1995 and May 2009. Fourteen patients were diagnosed incidentally (54%). Five patients (19%) presented with dyspnea or shortness of breath, 4 (15%) with pain, 1 (4%) with pneumonia, 1 (4%) with hoarseness, and 1 (4%) with Horner syndrome.

Results

Pathology demonstrated schwannomas in 20 patients (77%). Other diagnoses included ganglioneurofibroma, paraganglioma, epithelioid angiosarcoma, benign hemangioma, benign granular cell tumor, and infectious granuloma. One patient required conversion to open thoracotomy due to pleural scarring to the tumor. One underwent initial laminectomy due to intraspinal extension of the tumor. Gross-total resection was obtained in 25 cases (96%). The remaining patient underwent biopsy followed by radiation therapy. The mean surgical time was 2.5 hours, and the mean blood loss was 243 ml. The mean duration of chest tube insertion was 1.3 days, and the mean length of hospital stay was 3.0 days. Cases that were treated in the second half of the cohort were more often diagnosed incidentally, performed in less time, and had less blood loss than those in the first half of the cohort. There was 1 case of permanent treatment-related morbidity (mild Horner syndrome). All previously employed patients were able to return to work (mean clinical follow-up 43 months). There were no recurrences (mean imaging follow-up 54 months).

Conclusions

Endoscopic transthoracic approaches can reduce approach-related soft-tissue morbidity and facilitate recovery by preserving the normal tissues of the chest wall, by avoiding rib retraction and muscle transection, and by reducing postoperative pain. This less invasive approach thus shortens hospital stay and recovery time.

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Aristotelis S. Filippidis, M. Yashar Kalani, Nicholas Theodore and Harold L. Rekate

Object

The definition of tethered cord syndrome (TCS) relies mainly on radiological criteria and clinical picture. The presence of a thickened filum terminale and a low-lying conus medullaris in symptomatic patients is indicative of TCS. The radiological definition of TCS does not take into account cases that involve a normal-lying conus medullaris exhibiting symptoms of the disease.

Methods

The authors performed a MEDLINE search using the terms “tethered cord” and “pathophysiology.” The search returned a total of 134 studies. The studies were further filtered to identify mostly basic research studies in animal models or studies related to the biomechanics of the filum terminale and spinal cord.

Results

Spinal cord traction and the loss of filum terminale elasticity are the triggers that start a cascade of events occurring at the metabolic and vascular levels leading to symptoms of the disease. Traction on the caudal cord results in decreased blood flow causing metabolic derangements that culminate in motor, sensory, and urinary neurological deficits. The untethering operation restores blood flow and reverses the clinical picture in most symptomatic cases.

Conclusions

Although classically defined as a disease of a low-lying conus medullaris, the pathophysiology of TCS is much more complex and is dependent on a structural abnormality, with concomitant altered metabolic and vascular sequelae. Given the complex mechanisms underlying TCS, it is not surprising that the radiological criteria do not adequately address all presentations of the disease.

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Theodore M. Liszczak, Peter McL. Black, Argyris Tzouras, Lorraine Foley and Nicholas T. Zervas

✓ Experimental subarachnoid hemorrhage (SAH) was induced in adult rabbits by three repeated cisterna magna injections of autologous nonheparinized blood. One week after the last blood injection the animals were sacrificed and examined for morphological change.

No vasculopathy was noted in the basilar arteries and no periarterial thrombus was seen around the majority of these arteries. Gross and microscopic changes were observed in both the ventricles and choroid plexus. Ventricular changes included dilation of the lateral ventricles, destruction of ciliated ependymal cells, and deposition of small amounts of blood throughout the ventricular system. These ventricular changes are similar to the pathological sequelae of SAH in patients. Choroid plexus changes included electron-dense cytoplasmic inclusions and dilation of the lateral and subcellular spaces. The ventricular surface and the choroid plexus are both affected by the intracisternal injection of blood. The hydrocephalus that follows SAH may be potentiated by ependymal disruption and loss of ciliated activity in the ventricles. Changes in choroid plexus function may also occur.

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Giriraj K. Sharma, Jennifer M. Eschbacher, Timothy D. Uschold and Nicholas Theodore

Neuroblastoma-like schwannoma is a rare nerve sheath tumor with histological features resembling a neuroblastoma. A comprehensive literature review identified only 10 previous case reports of this condition. The authors present the first reported case of a neuroblastoma-like schwannoma at a spinal nerve root. The patient, a 61-year-old woman, presented with severe pain in the right lower extremity that failed to resolve after conservative management. Magnetic resonance imaging revealed an intradural enhancing lesion extending out of the right neural foramen at L1–2. A right L1–2 hemilaminectomy and facetectomy with gross-total resection of the tumor was performed without complications. Neuroblastoma-like schwannoma was diagnosed based on histopathological examination of the biopsied tumor specimen. A postoperative course of serial examination and imaging was chosen based on a suspected benign postoperative course as in the case of a completely resected schwannoma. The authors present the novel case of neuroblastoma-like schwannoma at a lumbar spinal nerve root and describe the distinguishing pathological features of this rare lesion.

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Nicholas Theodore, M. Yashar S. Kalani and Volker K. H. Sonntag

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Samuel Kalb, Nikolay L. Martirosyan, Luis Perez-Orribo, M. Yashar S. Kalani and Nicholas Theodore

Object

Ossification of the posterior longitudinal ligament (OPLL) is a rare disease that results in progressive myeloradiculopathy related to pathological ossification of the ligament from unknown causes. Although it has long been considered a disease of Asian origin, this disorder is increasingly being recognized in European and North American populations. Herein the authors present demographic, radiographic, and comorbidity data from white patients with diagnosed OPLL as well as the outcomes of surgically treated patients.

Methods

Between 1999 and 2010, OPLL was diagnosed in 36 white patients at Barrow Neurological Institute. Patients were divided into 2 groups: a group of 33 patients with cervical OPLL and a group of 3 patients with thoracic or lumbar OPLL. Fifteen of these patients who had received operative treatment were analyzed separately. Imaging analysis focused on signal changes in the spinal cord, mass occupying ratio, signs of dural penetration, spinal levels involved, and subtype of OPLL. Surgical techniques included anterior cervical decompression and fusion with corpectomy, posterior laminectomy with fusion, posterior open-door laminoplasty, and anterior corpectomy combined with posterior laminectomy and fusion. Comorbidities, cigarette smoking, and previous spine surgeries were considered. Neurological function was assessed using a modified Japanese Orthopaedic Association Scale (mJOAS).

Results

A high-intensity signal on T2-weighted MR imaging and a history of cervical spine surgery correlated with worse mJOAS scores. Furthermore, mJOAS scores decreased as the occupying rate of the OPLL mass in the spinal canal increased. On radiographic analysis, the proportion of signs of dural penetration correlated with the OPLL subtype. A high mass occupying ratio of the OPLL was directly associated with the presence of dural penetration and high-intensity signal. In the surgical group, the rate of neurological improvement associated with an anterior approach was 58% compared with 31% for a posterior laminectomy. No complications were associated with any of the 4 types of surgical procedures. In 3 cases, symptoms had worsened at the last follow-up, with only a single case of disease progression. Laminoplasty was the only technique associated with a worse clinical outcome. There were no statistical differences (p > 0.05) between the type of surgical procedure or radiographic presentation and postoperative outcome. There was also no difference between the choice of surgical procedure performed and the number of spinal levels involved with OPLL.

Conclusions

Ossification of the posterior longitudinal ligament can no longer be viewed as a disease of the Asian population exclusively. Since OPLL among white populations is being diagnosed more frequently, surgeons must be aware of the most appropriate surgical option. The outcomes of the various surgical treatments among the different populations with OPLL appear similar. Compared with other procedures, however, anterior decompression led to the best neurological outcomes.

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Mohammed A. Eleraky, Nicholas Theodore, Mark Adams, Harold L. Rekate and Volker K. H. Sonntag

Object. To evaluate and review their experience with pediatric cervical injuries and factors affecting outcome, the authors conducted a retrospective clinical study of 102 cases (65% boys, 35% girls) of pediatric cervical spine injuries treated in the last decade. This study is an extension of and comparison with their earlier experience.

Methods. Patients were divided into two age groups—birth to 9 years (Group 1) and 10 to 16 years of age (Group 2)—and managed according to status at presentation and type of injury. Thirty patients were managed surgically and 72 nonsurgically (42 wore a halo brace and 30 wore hard collars or custom-molded braces).

Motor vehicle accidents were the most common cause of injury, and 40% were associated with head injury. Patients in the younger-age group (Group 1) sustained more neurological injuries than the older patients in Group 2, and most injuries were in the upper cervical spine. Of the 38 children in Group 1, in 39% a subluxation was present and in 29% a fracture or fracture/subluxation was demonstrated. Of the patients in Group 2, 80% had sustained fractures or fracture/subluxations. Vertebral fractures were the most common radiological findings (32%). At late follow-up review (mean 5 years), solid fusions were demonstrated in all patients. Neurological deterioration did not occur in any patient. The mortality rate was 16%. Compared with the authors' earlier report, the incidence of cases with pediatric cervical injuries increased, as did the number managed surgically. Various fusion techniques were used, and neurological and fusion outcomes improved as compared with the previous report.

Conclusions. The prognosis of neurological recovery from pediatric cervical spine injuries is related to the severity of the initial neurological injury. Management must be tailored to the patient's age, neurological status, and type and level of injury. Compared with our earlier experience, fusion and instrumentation procedures were used more frequently. Different types of fusion and instrumentation procedures can be performed safely in children and produce good outcomes.

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Justin F. Fraser, Gurston G. Nyquist, Nicholas Moore, Vijay K. Anand and Theodore H. Schwartz

Object

Transcranial approaches to clival chordomas provide a circuitous route to the site of origin of the tumor often involving extensive bone drilling and brain retraction, which places critical neurovascular structures between the surgeon and pathology. For certain chordomas, the endonasal endoscopic transclival approach is a novel minimal access, but it is an equally aggressive alternative providing the most direct route to the tumor epicenter.

Methods

The authors present a consecutive series of patients undergoing endonasal endoscopic resection of clival chordomas. Extent of resection was determined by postoperative volumetric MR imaging and divided into > 95% and < 95%.

Results

Seven patients underwent 10 operations. Preoperative cranial neuropathies were present in 4. The mean patient age was 52.0 years. The mean tumor volume was 34.9 cm3. Intraoperative lumbar drainage was used in 1 patient, and the tumors extended intradurally in 3. One patient underwent 2 intentionally palliative procedures for subtotal debulking. Greater than 95% resection was achieved in 7 of 8 operations in which radical resection was the goal (87%). All tumors with volumes < 50 cm3 had > 95% resection (p = 0.05). The overall mean follow-up was 18.0 months. Cranial neuropathies resolved in all 3 patients with cranial nerve VI palsies. One patient with recurrent nasopharyngeal chordoma died of disease progression; another experienced 2 recurrences before receiving radiation therapy. All surviving patients remain progression free. There were no intraoperative complications; however, 1 patient developed a pulmonary embolus postoperatively. There were no postoperative CSF leaks.

Conclusions

The endonasal endoscopic transclival approach represents a less invasive and more direct approach than a transcranial approach to treat certain moderate-sized midline skull base chordomas. Longer follow-up is necessary to determine comparability to transcranial approaches for long-term control. Large tumors with significant extension lateral to the carotid artery may not be suitable for this approach.

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Eduardo Martinez-del-Campo, Leonardo Rangel-Castilla, Hector Soriano-Baron and Nicholas Theodore

Object

Performance of MR imaging in patients with gunshot wounds at or near the lumbar spinal canal is controversial. The authors reviewed the literature on the use of MR imaging in gunshot wounds to the spine. They discuss the results from in vitro and clinical studies, analyze the physical properties of common projectiles, and evaluate the safety and indications for MR imaging when metallic fragments are located near the spinal canal.

Methods

A review of the English-language literature was performed. Data from 25 articles were analyzed, including 5 in vitro studies of the interaction between 95 projectiles and the MR system's magnetic fields, and the clinical outcomes in 22 patients with metallic fragments at or near the spinal canal who underwent MR imaging.

Results

Properties of 95 civilian and military projectiles were analyzed at a magnet strength of 1, 1.5, 3, and 7 T. The most common projectiles were bullets with a core of lead, either with a copper jacket or unjacketed (73 [76.8%] of 95). Steel-containing (core or jacket) projectiles comprised 14.7%. No field interaction was evident in 78 (96.3%) of the 81 nonsteel projectiles. All steel projectiles showed at least positive deflection forces, longitudinal migration, or rotation. Heating of the projectiles was clinically insignificant. Image artifact was significant in all 9 steel bullets tested, but was not significant in 39 (88.6%) of the 44 nonsteel bullets tested. Overall, 22 patients with complete (82%) and incomplete (14%) spinal cord injury secondary to a projectile lodged inside the spinal canal underwent MR imaging. Discomfort and further physical or neurological deficits were not reported by any patient. Two patients with spinal cord injuries underwent MR imaging studies before surgical decompression and had subsequent, significant neurological improvement.

Conclusions

Metallic implants near or at the spinal canal are a relative contraindication for MR imaging. However, safe MR imaging might be feasible when a projectile's properties and a patient's individualized clinical presentation are considered.