Monitoring rate and predictability of intraoperative monitoring in patients with intradural extramedullary and epidural metastatic spinal tumors.

STUDY DESIGN: Single-center retrospective study. OBJECTIVES: To evaluate the monitoring rate, sensitivity and specificity of intraoperative monitoring (IOM) during removal of intradural extramedullary (IDEM) or epidural metastatic spinal tumors. Also, to assess the efficacy of monitoring somatosensory-evoked potentials (SSEP) when motor-evoked potentials (MEP) are not measurable. SETTING: The Neuro-Oncology Clinic, National Cancer Center, Korea. METHODS: Patients (n=101) with IDEM or epidural metastatic spinal tumors at the cord level underwent surgeries monitored with SSEP and/or MEP. The monitoring rate was defined as negative when MEP or SSEP could not be measured after reversal of the neuromuscular block under general anesthesia. Positive IOM changes included more than a 50% change in the MEP or SSEP amplitude and more than a 10% delay in SSEP latency. RESULTS: MEP was measurable in 73% of patients. The MEP monitoring rate in patients with motor power grades of 3 or less was 39%, which was lower than that of SSEP (83%). The sensitivity, specificity and predictability of MEP for motor changes were 93, 90 and 91%, respectively. Conversely, the sensitivity, specificity and predictability of SSEP were 62, 97 and 89%, respectively. In patients in whom MEP was not measurable (n=24), SSEP was monitored with a predictability of 83%. CONCLUSION: In cases of extramedullary spinal tumors, MEP shows a higher sensitivity than SSEP does. However, the monitoring rate of MEP in non-ambulatory patients was lower than that of SSEP. In those cases, SSEP can be useful to monitor for postoperative neurological deficits.

[Relationship of motor deficits and imaging features in metastatic epidural spinal cord compression].

OBJECTIVE: To explore the relationship of motor deficits of the lower extremities with the imaging features of malignant spinal cord compression (MESCCs). METHODS: From July 2006 through December 2008, 56 successive MESCC patients were treated at our department. All were evaluated by magnetic resonance imaging and computed tomography and were scored according to motor deficits Frankel grading on admission. Imaging assessment factors of main involved vertebrae were level of vertebral metastatic location, epidural space involvement, vertebral body involvement, lamina involvement, posterior protrusion of posterior wall, pedicle involvement, continuity of main involved vertebrae, fracture of anterior column, fracture of posterior wall, location in upper thoracic spine and/or cervicothoracic junction. RESULTS: Occurrence was the same between paralytic state of MESCCs and epidural space involvement of imaging features. Multiple regression equation showed that paralytic state had a linear regression relationship with imaging factors of lamina involvement (X1), posterior protrusion of posterior wall (X2), location in upper thoracic spine and/or cervicothoracic junction (X7) of main involved vertebrae. The optimal regression equation of paralytic state (Y) and imaging feature (X) was Y = -0.009 +0.639X, + 0.149X, +0.282X. Lamina involvement of main involved vertebrae has a greatest influence upon paralytic state of MESCC patients. CONCLUSIONS: Imaging factors of lamina involvement, posterior protrusion of posterior wall, location in upper thoracic spine and/or cervicothoracic junction of main involved vertebrae can predict the paralytic state of MESCC patients. MESCC with lamina involvement is more easily encroached on epidural space.

Effect of hyperglycemia on progressive paraparesis in a rat etastatic spinal tumor model.

OBJECT: Hyperglycemia has been shown to potentiate ischemic injury of the spinal cord by quenching vasodilators and potentiating tissue acidosis and free radical production. Steroid-induced hyperglycemia is a common event in the surgical management of metastatic epidural spinal cord compression (MESCC). The goal in this study was to determine whether experimentally induced hyperglycemia accelerates neurological decline in an established animal model of MESCC. METHODS: Sixteen Fischer 344 rats underwent a transabdominal approach for implantation of a CRL-1666 breast adenocarcinoma cell line within the vertebral body of L-6. After 72 hours of recovery from tumor implantation, the animals received intraperitoneal injections every 12 hours of either 2 g/kg dextrose in 5 ml 0.09% saline (hyperglycemia, 8 rats) or 5 ml 0.09% saline alone (normoglycemia, 8 rats). Weights were taken daily, and the hindlimb function was tested daily after tumor implantation by using the Basso-Beattie-Bresnahan (BBB) scale (score range 1-21). Animals were killed at time of paralysis (BBB Score < 7), and the volume of epidural tumor growth within the spinal canal was measured. To determine the degree of hyperglycemia induced by this dextrose regimen, a surrogate group of 10 Fischer 344 rats underwent intraperitoneal injections of 2 g/kg dextrose (5 rats) or 0.09% saline (5 rats) every 12 hours, and serum glucose levels were assessed 1, 3, 6, 8, 10, and 12 hours after injections for 24 hours. RESULTS: Dextrose versus saline injections resulted in elevated mean serum glucose at 3 (259 vs 103 microg/dl), 6 (219 vs 102 microg/dl), 8 (169 vs 102 microg/dl), and 10 hours (118 vs 99 microg/dl) after injection, returning to normal levels by 12 hours (96 vs 103 microg/dl) just prior to subsequent injection. All rats had normal hindlimb function for the first 8 days after tumor implantation. Hyperglycemic versus normoglycemic rats demonstrated a worsened median BBB score by postimplantation Day 9 (Score 20 vs 21, p = 0.023) through Day 16 (Score 8 vs 12, p = 0.047). Epidural tumor volume demonstrated a near-linear growth rate across both groups; however, hyperglycemic rats developed paralysis earlier (median 15.5 vs 17.5 days, p = 0.0035), with significantly less epidural tumor volume (2.75 +/- 0.38 cm(3) vs 4 +/- 0.41 cm(3), p < 0.001) at time of paralysis. CONCLUSIONS: In a rat model of metastatic epidural spinal cord compression, rats maintained in a hyperglycemic state experienced accelerated time to paralysis. Also, less epidural tumor volume was required to cause paralysis in hyperglycemic rats. These results suggest that hyperglycemic states may contribute to decreased spinal cord tolerance to compression resulting from MESCC. Clinical studies evaluating the effect of aggressive glucose control in patients with MESCC may be warranted.

Spinal cord evoked potential monitoring after spinal cord stimulation during surgery of spinal cord tumors.

Spinal cord evoked potentials (SCEPs) after spinal cord stimulation were used as a method of spinal cord monitoring during surgery of 6 extramedullary and 14 intramedullary spinal cord tumors. SCEPs were recorded from an epidural electrode placed rostral to the level of the tumor. Electrical stimulation was applied on the dorsal spinal cord from a caudally placed epidural electrode. The wave forms of SCEPs consisted of a sharp negative peak (N1) in 15 cases and two negative peaks (N1 and N2) in 5 cases. The N2 wave was markedly attenuated by posterior midline myelotomy, whereas the N1 activity showed less-remarkable changes by myelotomy. An increase in N1 amplitude was observed after the removal of the tumor in four extramedullary and three intramedullary cases. Of six patients that showed decreased N1 amplitude after the removal of the tumor, five patients developed postoperative motor deficits. However, there were four false-negative cases and one false-positive case in regard to changes of N1 amplitude and postoperative motor deficits. Four false results occurred in intramedullary cases. In two of them, postoperative symptoms indicated intraoperative unilateral damage to the spinal cord. The position of the stimulating electrode, the difference in thresholds of the axons for electrical stimulation between the right and left side of the spinal cord, or the change of the distance between the electrode and the spinal cord surface may account for these false results. Thus, our analysis of the changes of SCEP wave forms and early postoperative symptoms indicates that the sensitivity of this monitoring method to detect intraoperative insults to the spinal cord is unsatisfactory in spite of the reproducible wave forms. We conclude that SCEP monitoring can be used as an alternative method or in combination with other types of evoked potentials in patients with severe spinal cord lesions who show abnormal somatosensory evoked potentials preoperatively.

Glomangioma at the cervical spine as an extradural dumbbell-shaped tumor--a case report.

A case of glomangioma located at an unusual site, the extradural space of the cervical spine, is presented. To our knowledge, this is the first case that has been identified at this location. Radiographic features of computed tomography (CT) and magnetic resonance (MR) image were collected as a dumbbell-shaped tumor at epidural space of the cervical spine. These features correspond with the histological findings.

Spinal epidural metastases: a common problem for the primary care physician.

Spinal metastases are a common complication of cancer that should be managed quickly and aggressively. Most often from lung or breast cancer (or due to lymphoma), they usually seed from blood into vertebrae and extend into the epidural space. The most common presentation is pain and weakness, and the evolution can be rapid with paraplegia within days. Better prognosis is related to slower onset and pretreatment motor status, so spinal metastases are an emergency. Testing includes X-rays, neuroimaging, myelogram/CT and most recently MRI. Treatment is guided by the severity of neurological deficits, whether compression is by soft tissue or bone, and the presence of instability. A soft tissue mass with only mild to moderate deficits can be treated with radiation. Surgery is required for severely affected patients who are deteriorating rapidly with instability and bone in the canal. New approaches and fusion techniques facilitate decompression and stabilization.

[Spinal extradural angiolipoma: a case report].

Growth of angiolipoma of the central nervous system is a rare occurrence. Only about 40 cases can be collected in the literature. A 67-year-old man was admitted because of intermittent severe pain in both legs after walking. He had chillness in both legs during the past 5 years which gradually worsened. MR image showed a spinal mass lesion at the level of Th12 to L1. The lesion was isointense on T1-weighted image and slightly hyperintense on T2-weighted image. The tumor was located on the left side of the spinal cord and was markedly enhanced after intravenous Gd-DTPA. At the operation, a soft, dark-red mass was found situated in the epidural space at the level of Th12 to L1, which was totally removed. On histological examination, the tumor was shown to be mainly composed of mature fatty cells and of numerous blood vessels with enlarged lumens. Postoperative course was uneventful and the symptoms subsided during the following few months.

Widespread vertebral and epidural venous plexus metastasis of prostatic carcinoma presenting wedge-shaped radial lesions in the spinal cord.

The present case is the first autopsy case of prostatic carcinoma presenting widespread spinal epidural venous plexus tumor cell emboli with wedge-shaped spinal cord lesions. There has been no previous report of prostatic carcinoma showing tumor cell emboli in the spinal and cranial base epidural venous plexus, in spite of the fact that the incidence of vertebral metastasis in prostatic carcinoma is high, and that presence of continuity from pelvic organs to venous plexus around vertebrae, up to foramen magnum, has been reported. The present case shows that the possibility of spinal cord injury, not by direct compression, but by venous circulatory disturbance as a result of tumor cell emboli to veins, should be taken into consideration on medical treatment of prostatic carcinoma.

Outcome after spinal reirradiation for malignant epidural spinal cord compression.

Radiotherapy is effective for most cases of spinal cord compression. Although recurrent spinal cord compression is a common problem, little is known about whether reirradiation preserves neurologic function and what risk of radiation myelopathy it carries. To investigate this question, we reviewed patients at the Mayo Clinic between 1975 and 1992 undergoing two or more courses of radiotherapy to the same segment of the spinal column with radiographically documented epidural disease at the time of reirradiation to determine outcome as measured by the ability to walk and by survival. Fifty-four patients met the study criteria. Radiation doses for the first course ranged from 2,250 to 5,400 cGy (median, 3,000 cGy), and total dose for all courses to the reirradiated spinal segment ranged from 3,650 to 8,089 cGy (median, 5,425 cGy). All patients were ambulatory following the first course of radiation, 40 (74%) were ambulatory at the onset of reirradiation, and 42 (78%) were ambulatory at the end of reirradiation. Thirty-seven patients (69%) remained ambulatory at their last follow-up 6 days to 80 months following reirradiation (median, 4.7 months). Five patients eventually became nonambulatory 6.5 to 35 months following reirradiation. Median survival for all patients following reirradiation was 4.2 months. We conclude that for cancer patients with progressive epidural disease following radiotherapy, reirradiation frequently preserves ambulation and carries minimal risk of radiation myelopathy during the patients' lifetime.

Epidural thoracal teratoma in a 7-month-old girl.

CASE REPORT: We report a rare case of epidural thoracal teratoma in a 7-month-old girl. A total laminectomy was performed via T6-T8 and the lesion was totally excised. RESULTS AND DISCUSSION: We describe the radiological, surgical and pathological findings in this patient and review the findings in other reported cases.

A case of idiopathic spinal epidural lipomatosis presented with radicular pain caused by compression with enlarged veins surrounding nerve roots.

OBJECTIVE: To report a case of idiopathic spinal epidural lipomatosis (SEDL) presented with unique radicular pain most likely caused by enlarged veins surrounding nerve roots. PATIENT: A 26-year-old male presented with radicular pain of the right T6-T7 area. He also showed Becker's nevus in the corresponding area. CT myelography and magnetic resonance imaging revealed epidural lipomatosis posterior to T4-T8 of the spinal cord. Surgical removal of adipose tissue and a hemilaminectomy of T4-T7 were performed and resulted in relief of the radicular pain. CONCLUSIONS: Lipomatosis was histologically confirmed and surrounded by enlarged veins. These abnormally enlarged veins compressed the nerve roots and were thought to cause radicular pain. Also, Becker's nevus of this case seems to have some relationship with SEDL.

Calcifying pseudo-tumor of the spine: description of a case and review of the literature.

A case of calcifying pseudo-tumor of the thoracic spine, a rare lesion with tumor-like behavior and a probable inflammatory-reactive origin, is described. The clinical-pathological and neuro-radiological aspects of this lesion are discussed in relation to surgical treatment. In accordance with the other cases reported in the literature, the case observed confirmed the benign behavior of the lesion and the effectiveness of surgical treatment for achieving complete resolution of clinical symptoms without any recurrences, even when removal is only subtotal.

Diretrizes no tratamento das metástases epidurais da coluna vertebral: atualização / Guidelines for treatment of epidural spinal metastases

Objetivo: Atualizar conceitos e recomendar condutas da prática médica nos aspectos de prognóstico,diagnóstico e tratamento das metástases epidurais da coluna vertebral. Método: O período de apuração das publicações situou-se entre janeiro de 1990 a janeiro de 2006, incluídas as referências relevantes prévias. A ausência de evidências de valor científico para determinar padrões ou diretrizes de conduta em temas médicos que geram incertezas da prática, permite usar do termo diretrizes para todas as recomendações. Resultados: A modalidade de tratamento a ser escolhido depende da análise dos fatores preditivos de prognóstico, tais como: o estado clínico do doente; a possibilidade de resgatar ou manter a capacidade de deambulação; grau de disseminação e transmissão da neoplasia primária.As informações obtidas com o diagnóstico de imagem da ressonância magnética efetuada em toda a extensão da coluna vertebral e o complemento das imagens ósseas pertinentes da tomografia axial computadorizada são necessárias na escolha e implementação do tratamento escolhido. O tratamento cirúrgico inclui a descompressão circunferencial da medula espinhal, a reconstrução do corpo vertebral e a estabilização segmentar da coluna vertebral. Conclusões: As recomendações conferem eficácia e eficiência nas condutas médicas. O prognóstico depende dos fatores preditivos de sobrevivência.Os exames complementares de imagem auxiliam no estadiamento e planejamento do tratamento.A modalidade de tratamento escolhida depende da previsão de sobrevivência e da capacidade de deambulação do doente.

Objective: Bring up-to-date concepts and conduct practice parameters recomendations concerningaspects in prognosis, diagnosis and treatment of spinal epidural metastases. Method: Pertinent publications between January, 1990 and January, 2006, including previous relevant medical articles were reviewed. The absence of scientific value for evidence to determine conduct standards or guidelines in uncertain medical practice allows to use as guideline all recomendations. Results: The choice of a treatment modality depends on predictive prognosis factors, such as: patient’s clinical state; preservation or salvage of walking capabilty; primary cancer spreading and transmission grade. Diagnostic information obtained by magnetic ressonance imaging of the spinal column complemented by pertinent computorized axial tomography bone images are necessary to choose and implement the treatment modality. Surgical treatment includes: circumferential spinal cord decompression; vertebral body reconstruction; segmental vertebral column stabilization. Conclusions: Recommendations bestow efficacy and efficiency of medical conducts. Complementary imaging studies are useful to determine the treatment, staging and planning. Treatment modality to be chosen depends on the patients’ survival expectancy and their capability to walk.

Compresión epidural neoplásica. Nuevas alternativas terapéuticas / Neoplastic spinal cord compression. New therapeutic alternatives

La compresión epidural neoplásica (CEN) es una complicación frecuente en pacientes oncológicos, la fisiopatología del mismo es poco comprendida y generalmente relacionada a un efecto mecánico: el tratamiento convencional incluye la utilización de corticoides y radioterapia. Se han demostrado tres nuevos aspectos en la fisiopatología de la CEN: 1) El rol protagónico de la prostaglandina E2 (PGE2) en el incremento de la permeabilidad vascular y la formación del edema de tipo vasogénico. 2) El neurotrasmisor serotonina que actúa estimulando tanto la producción de PGE2 como la acción neurotóxica de los aminoácidos exitatorios. 3) La acción de las exitotoxinas en el daño tisular neural secundario a la alteración del flujo de sodio, cloro y calcio. Estos tres aspectos fisiopatológicos tienen su respaldo en 1) Indometacina como inhibidor de la producción de PG. 2) Ciproheptadina, p-clorofenilalanina y ketanserina como antiserotoninérgicos. 3) MK-801 y ketamina como antagonistas del glutamato. El uso racional de estos fármacos pueden contribuir a retardar la instalación del cuadro neurológico permitiendo la mejor utilización de terapias más definitivas