Lumbar disc arthroplasty is now a common treatment for lumbar degenerative disc disease. Whereas the immediate and delayed complications in patients with artificial lumbar discs are well reported, the durability of artificial disc hardware after severe spine trauma is unknown. The authors describe the management of a rare case of a traumatic lumbar burst fracture in a patient who had undergone disc arthroplasty. This 31-year-old male contractor had undergone placement of an L4–5 Charité artificial disc (DePuy Spine) and L5–S1 anterior lumbar fusion 10 months before he fell from a roof and sustained a traumatic L-3 burst fracture with significant canal compromise and cauda equina injury. Despite the considerable compressive load on his spine, the artificial disc (L4–5) remained intact without any radiological signs of hardware failure, and the vertebrae above (L-4) and below (L-5) the artificial disc had no signs of injury. For the L-3 burst fracture the patient underwent an open decompressive laminectomy at L2–3 and posterior fusion with instrumentation from L-2 to L-4. At 24 months postinjury, he had returned to full work activities as a contractor with minimal back pain and mild right lower-extremity sensory changes and weakness left over from the trauma. The total disc arthroplasty at L4–5 is functional and has preserved motion, and there is a solid fusion at L2–4 and L5–S1. This case demonstrates that a lumbar artificial disc can tolerate a significant load from trauma and remain functional without hardware failure even after a traumatic burst fracture at the adjacent lumbar vertebral body and shows the successful treatment of this fracture, with posterior fusion preserving the motion of an artificial disc.
Oren N. Gottfried and Darrel S. Brodke
Oren N. Gottfried and William T. Couldwell
Carotid endarterectomy is more effective than medical management in the prevention of stroke in patients with severe symptomatic or asymptomatic atherosclerotic carotid-artery stenosis. Stenting with the use of an emboli-protection device is a less invasive revascularization strategy than endarterectomy in carotid-artery disease.
We conducted a randomized trial comparing carotid-artery stenting with the use of an emboli-protection device to endarterectomy in 334 patients with coexisting conditions that potentially increased the risk posed by endarterectomy and who had either a symptomatic carotid-artery stenosis of at least 50 percent of the luminal diameter or an asymptomatic stenosis of at least 80 percent. The primary end point of the study was the cumulative incidence of a major cardiovascular event at 1 year—a composite of death, stroke, or myocardial infarction within 30 days after the intervention or death or ipsilateral stroke between 31 days and 1 year. The study was designed to test the hypothesis that the less invasive strategy, stenting, was not inferior to endarterectomy.
The primary end point occurred in 20 patients randomly assigned to undergo carotid-artery stenting with an emboli-protection device (cumulative incidence, 12.2 percent) and in 32 patients randomly assigned to undergo endarterectomy (cumulative incidence, 20.1 percent; absolute difference, −7.9 percentage points; 95 percent confidence interval, −16.4 to 0.7 percentage points; P=0.004 for noninferiority, and P=0.053 for superiority). At one year, carotid revascularization was repeated in fewer patients who had received stents than in those who had undergone endarterectomy (cumulative incidence, 0.6 percent vs. 4.3 percent; P=0.04).
Among patients with severe carotid-artery stenosis and coexisting conditions, carotid stenting with the use of an emboli-protection device is not inferior to carotid endarterectomy.
Daniel B. Loriaux, Owoicho Adogwa and Oren N. Gottfried
A true adult spinal lipoma is an exceedingly rare cause of lumbar compression neuropathy. Only 5 cases of true extradural intraforaminal lipomas have been documented in the medical literature. The diagnostic criteria and treatment guidelines for this specific lipoma have yet to be established. This report features 3 histologically confirmed cases of extradural intraforaminal spinal lipomas that recently presented to the authors’ practice. In addition, the literature was surveyed to include the 5 previously reported cases of true adult extradural intraforaminal spinal lipomas. The consistency in presentation, response to surgical intervention, and postoperative recovery in these 8 cases supports surgical intervention at the time of diagnosis. The authors’ findings support elevated clinical suspicion, efficient diagnosis based on MRI, and early surgical intervention for this rare pathological entity. All cases presented in this report were symptomatic and occurred in the absence of other significant pathologies such as general spinal epidural lipomatosis, intradural lesions, tethering, or severe degenerative stenosis or herniated discs. The clinical, neuroradiological, and histological findings characteristic of a true adult extradural intraforaminal lipoma are emphasized to differentiate this lesion from the more common etiologies for lumbar compression neuropathy. Heightened awareness and clinical suspicion for the focal, foraminal spinal lipoma as a cause of radiculopathy symptoms will enable more efficient diagnosis and treatment.
Oren N. Gottfried, David H. Viskochil and William T. Couldwell
Neurofibromatosis Type 1 (NF1) is a common autosomal dominant disease characterized by complex and multicellular neurofibroma tumors, and less frequently by malignant peripheral nerve sheath tumors (MPNSTs) and optic nerve gliomas. Significant advances have been made in elucidating the cellular, genetic, and molecular biology involved in tumor formation in NF1. Neurofibromatosis Type 1 is caused by germline mutations of the NF1 tumor suppressor gene, which generally result in decreased intracellular neurofibromin protein levels, leading to increased cascade Ras signaling to its downstream effectors. Multiple key pathways are involved with the development of tumors in NF1, including Ras/mitogen-activated protein kinase (MAPK) and Akt/mammalian target of rapamycin (mTOR). Interestingly, recent studies demonstrate that multiple other developmental syndromes (in addition to NF1) share phenotypic features resulting from germline mutations in genes responsible for components of the Ras/MAPK pathway. In general, a somatic loss of the second NF1 allele, also referred to as loss of heterozygosity, in the progenitor cell, either the Schwann cell or its precursor, combined with haploinsufficiency in multiple supporting cells is required for tumor formation. Importantly, a complex series of interactions with these other cell types in neurofibroma tumorigenesis is mediated by abnormal expression of growth factors and their receptors and modification of gene expression, a key example of which is the process of recruitment and involvement of the NF1 +/– heterozygous mast cell. In general, for malignant transformation to occur, there must be accumulation of additional mutations of multiple genes including INK4A/ARF and P53, with resulting abnormalities of their respective signal cascades. Further, abnormalities of the NF1 gene and molecular cascade described above have been implicated in the tumorigenesis of NF1 and some sporadically occurring gliomas, and thus, these treatment options may have wider applicability. Finally, increased knowledge of molecular and cellular mechanisms involved with NF1 tumorigenesis has led to multiple preclinical and clinical studies of targeted therapy, including the mTOR inhibitor rapamycin, which is demonstrating promising preclinical results for treatment of MPNSTs and gliomas.
Oren N. Gottfried, Wayne M. Gluf and Meic H. Schmidt
Cavernous hemangioma of the calvaria is a very rare disease, and patients usually present with headaches or a visible skull deformity. Few reports of patients presenting with intradiploic or epidural hemorrhages are found in the literature. No case of an intradural hemorrhage from a cavernous hemangioma of the skull has been reported to date. The authors present the case of a 50-year-old man in whom a symptomatic subdural hematoma (SDH) resulting from a cavernous hemangioma of the calvaria had hemorrhaged and eroded through the inner table of the skull and dura mater. The patient underwent surgery for evacuation of the SDH and resection of the calvarial lesion. Postoperatively, the patient experienced immediate relief of his symptoms and had no clinical or radiological recurrence. Calvarial cavernous hemangiomas should be considered in the differential diagnosis of nontraumatic SDHs. Additionally, skull lesions that present with intracranial hemorrhages must be identified and resected at the time of hematoma evacuation to prevent recurrences.
Oren N. Gottfried, James K. Liu and William T. Couldwell
The optimal management of glomus jugulare tumors remains controversial. Available treatments were once associated with poor outcomes and significant complication rates. Advances in skull base surgery and the delivery of radiation therapy by stereotactic radiosurgery have improved the results obtained using these treatment options. The authors summarize and compare the contemporary outcomes and complications for these therapies.
Papers published between 1994 and 2004 that detailed the use of radiosurgery or surgery to treat glomus jugulare tumors were reviewed. Eight radiosurgery series including 142 patients and seven surgical studies including 374 patients were evaluated for neurological outcome, change in tumor size (radiosurgery) or percent of total resection (surgery), recurrences, tumor control, need for further treatment, and complications.
The mean age at treatment for patients who underwent surgery and radiosurgery was 47.3 and 56.7 years, respectively. The mean follow-up duration was 49.2 and 39.4 months, respectively. The surgical control rate was 92.1%, with 88.2% of tumors totally resected in the initial surgery. A cerebrospinal fluid leak occurred in 8.3% of patients who underwent surgery and recurrences were found in 3.1%; the mortality rate was 1.3%. Among patients who underwent radiosurgery, tumors diminished in 36.5%, whereas 61.3% had no change in tumor size, and subjective or objective improvements occurred in 39%. Despite the presence of residual tumor in 100% of radiosurgically treated patients, recurrences were found in only 2.1%, the morbidity rate was 8.5%, and there were no deaths.
Death and recurrences after these treatments are infrequent, and therefore both treatments are considered to be safe and efficacious. Although surgery is associated with higher morbidity rates, it immediately and totally eliminates the tumor. The radiosurgery results are very promising, although the incidence of late recurrence (after 10–20 years) is unknown.
Epidural venous engorgement resulting in progressive cervical myelopathy from shunt-related intracranial hypotension
Case report and review of the literature
James K. Liu, Oren N. Gottfried and Douglas L. Brockmeyer
✓The authors report an unusual case of engorged epidural veins causing progressive cervical myelopathy after long-term cerebrospinal fluid (CSF) shunt therapy and intracranial hypotension. An 18-year-old woman, who had previously undergone shunt placement with a distal slit valve for a porencephalic cyst when 2 years of age, presented with progressive spastic quadriparesis, numbness, and gait difficulty. Postural headaches were absent and a lumbar puncture revealed low CSF pressure. Neuroimaging disclosed markedly engorged anterior epidural veins causing compression of the cervical spinal cord. The slit-valve shunt system was surgically removed and an external drain was placed. The patient’s CSF pressure was gradually raised to clinically tolerable levels. Once the optimal pressure was identified, a programmable shunt was placed with the valve set at the same level. The patient’s neurological status improved, and the epidural veins had returned to their normal size on follow-up imaging. The authors describe the unique treatment strategy used in this patient and review the literature on epidural venous engorgement as it relates to intracranial hypotension.
Oren N. Gottfried, Meic H. Schmidt and Edwin A. Stevens
The management of sacral tumors is challenging because of difficulties in accessing the lesion, the high rate of local recurrence, extensive vascularity causing significant intraoperative blood loss, resistance to radiation therapy, and risk of malignant transformation. Although surgery is the main treatment for many sacral tumors, embolization is a valuable primary and adjunctive therapy. Patients with benign lesions, including aneurysmal bone cysts and giant cell tumors, have responded to embolization with resolution of their symptoms and with ossification of their lesions. Embolization is used as a primary therapy for metastatic lesions and results in neurological improvement, reduced tumor size, and decreased spinal canal compromise. It is also used as an adjuvant therapy to reduce intraoperative blood loss and to aid in the resection of benign, malignant, and metastatic sacral lesions. It is important to note that embolization techniques are a valuable resource in the treatment of sacral tumors, and, overall, embolization should always be considered in patients with sacral tumors.
James K. Liu, Oren N. Gottfried and William T. Couldwell
Posterior petrous meningiomas (commonly termed posterior pyramid meningiomas and/or meningiomas of the posterior surface of the petrous pyramid) are the most common meningiomas of the posterior cranial fossa. They are located along the posterior surface of the temporal bone in the region of the cerebellopontine angle. They often mimic vestibular schwannomas, both clinically and on neuroimaging studies. Common clinical symptoms include hearing loss, cerebellar ataxia, and trigeminal neuropathy. The site of dural origin determines the direction of cranial nerve displacement. Total resection can be achieved in most cases with a low morbidity rate and an excellent prognosis. The authors review the surgical management of posterior petrous meningiomas.
Oren N. Gottfried, Gary L. Hedlund, John M. Opitz and Marion L. Walker
The FG syndrome (FGS) is a common, heterogeneous group of clinically indistinguishable X-linked disorders comprising congenital hypotonia, macrocephaly, psychomotor delay, abnormalities in sensory integration, agenesis of corpus callosum, an unusual personality with behavior abnormalities, and disturbances of gastrointestinal function. On magnetic resonance (MR) imaging, some patients have evidence of tonsillar ectopia. The authors describe the incidence of Chiari I malformation in patients with FGS and attempt to determine the optimal treatment of these patients.
The authors performed a retrospective chart and radiological review of 144 pediatric patients with FGS for evidence of tonsillar ectopia on brain MR imaging. Eleven (7.6%) of these 144 patients had tonsillar ectopia, and in eight patients (5.6%), the tonsils were located more than 5 mm below the foramen magnum. Four of these patients underwent posterior fossa decompression, and surgery was performed at a mean age of 3 years. Indications for surgery included significant headaches and behavioral problems in two patients and failure to thrive with severe breathing and feeding difficulties in two infants. All four improved after surgery. The other patients remained asymptomatic from their tonsillar ectopia, showed no clinical or radiological signs of progression, and did not require surgery.
Chiari I malformation is more common in individuals with FGS than in the general population. Some of these patients with FGS require decompression surgery, but the decision to operate can be difficult because of their developmental delay, difficulties with language skills, general fatigue, possibility of upper motor neuron dysfunction, behavioral problems, or failure to thrive, which may mask the symptoms of a Chiari I malformation.