Nonenhancing tumors of the spinal cord

OBJECT: Enhancement of pathological entities in the central nervous system is a common finding when the blood-brain barrier has been compromised. In the brain, the presence or absence of gadolinium enhancement is often an indicator of tumor invasiveness and/or grade. In the spinal cord, however, contrast enhancement has been shown in all tumor types, regardless of grade. In this study the authors explore the incidence of nonenhancing tumors of the spinal cord and the clinical course of patients with these lesions. METHODS: A retrospective analysis was conducted in which investigators examined the patterns of enhancement of histologically proven intramedullary spinal cord tumors that had been evaluated at the Mayo Clinic between 1998 and 2002. The tumors that did not enhance were the subject of this report. RESULTS: A total of 130 patients with intramedullary tumors were evaluated. Of those, 11 patients (9%) had tumors that did not enhance. Histologically, a majority of tumors were astrocytomas (eight low-grade and two high-grade lesions); one tumor was a subependymoma. Morphologically, most of the tumors were diffuse and none had associated cysts. Tumors spanned from two to seven levels and were located throughout the spinal cord (four cervical, three cervicothoracic, one thoracic, and three thoracolumbar). Biopsy procedures were performed in eight patients, subtotal resection was performed in two, and gross-total resection in one. After a mean follow-up period of 19 months, tumors remained stable in eight patients but progressed in three, two of whom died. CONCLUSIONS: A number of intramedullary spinal cord tumors will not enhance after addition of contrast agents. The absence of enhancement does not imply the absence of tumor.     

Intradural arachnoid cysts of the spinal canal associated with intramedullary cysts

Five patients had intradural arachnoid cysts of the thoracic spinal canal associated with syringomyelia or posttraumatic intramedullary spinal cord cysts. Three cases were diagnosed 6 to 18 years after spinal surgery and two 14 to 17 years after spinal cord trauma. In each case, delayed progression of symptoms led to the identification of the lesions. The diagnosis was assisted by the use of myelography and delayed computerized tomography scanning in two cases and by magnetic resonance imaging in all five. In each case, the arachnoid cyst appeared to compress the spinal cord or nerve roots; in three cases, the syrinx cavities appeared to exert a significant mass effect. In the two trauma-related cases, the intramedullary cysts were small and may have represented areas of cystic myelomalacia. In four cases, intraoperative real-time ultrasonography helped to localize the arachnoid and intramedullary cavities. All five patients were treated by fenestration of the arachnoid cyst; additional peritoneal shunting of the cyst was performed in one case and of the intramedullary cavity in three. In one patient, the two lesions appeared to have a balancing effect; after drainage of the arachnoid cyst, the syrinx cavity expanded and had to be treated separately. The neurological deficits were reduced in four patients and stabilized in one. Intradural arachnoid cysts and intramedullary cysts may occur together as a late complication of spinal surgery or spinal cord trauma, and either or both lesions may cause delayed neurological deterioration.     

Intraoperative sonography for spinal tumors. Correlations with MR findings and surgery

BACKGROUND: To investigate the role of intraoperative ultrasonography during surgery for spinal tumors and the correlation between echographic, magnetic resonance and surgical findings. METHODS: Twenty patients with spinal tumor, explored by MRI of the spine, have been treated with ultrasound-guided surgery. The ultrasound exploration has been performed during laminectomy on the dural surface in all cases and, after the dural opening, on the spinal cord surface for intramedullary tumors. RESULTS: In all patients the ultrasound exploration has allowed to exactly define the extent of the laminectomy, the dural opening and the myelotomy. Meningiomas were hyperechoic and homogeneous, with well defined margins and often visible hyperechoic dural attachment; neurinomas were less hyperechoic and less homogeneous than meningiomas. Intramedullary tumors showed hyperechoic solid and hypoechoic cystic-necrotic components, although a specific tissue characterization (tumor infiltration, gliosis, edema) is not possible. CONCLUSIONS: Intraoperative ultrasonography should be used routinely during surgery for spinal tumors in order to reduce the extent of the laminectomy, dural opening and myelotomy. A good correlation exists between signal intensity on T1-weighted images of MR, the echographic aspect of the tumor and the pathological findings at operation.     

Intramedullary subependymoma of the cervical spinal cord: case report

The third case of intramedullary subependymoma of the cervical spinal cord is reported. This is the first such case for which intraoperative views are available. It was possible to remove most of this lesion with the aid of the operating microscope, the carbon dioxide laser, and the use of somatosensory evoked potentials. The diagnosis was clouded by the coexistence of Holmes-Adie pupils and absent reflexes in the lower extremities. All three reported intramedullary subependymomas have been found in the cervical spinal cord of middle-aged patients. Tumors in this clinical setting should not be assumed to be unresectable astrocytomas without careful histopathological and intraoperative evaluation.     

Spinal cord gliomas and hydrocephalus: utility of neuroendoscopy.

OBJECTIVE: The aim of this study is to report on the role of neuroendoscopy during the management of hydrocephalus that led to the diagnosis of intracranial tumoral dissemination and the subsequent finding of a spinal cord glioma. METHODS AND RESULTS: We present two children each with an intramedullary astrocytoma that presented initially with hydrocephalus without spinal cord symptoms. In both cases leptomeningeal gliomatous dissemination was asserted during routine endoscopy for the management of hydrocephalus. The diagnosis of a cervical and a lower thoracic intramedullary tumor was made soon after on magnetic resonance imaging. CONCLUSIONS: Spinal cord MRI with contrast should be considered initially in selected cases of hydrocephalus without evident diagnosis. The intraoperative diagnosis of gliomatous dissemination and secondary hydrocephalus due to unrecognized spinal cord gliomas was possible, in our experience, with the routine use of the neuroendoscope.     

Clinical values of intraoperative ultrasonography for spinal tumors.

Intraoperative ultrasonography was conducted in 52 cases of spinal tumor, at 7.5 MHz, mainly by means of linear scanning, to evaluate its clinical usefulness. The procedure was effectively applied in such clinical purposes as: 1) locating the tumor, 2) deciding the resectability of intramedullary tumors, 3) deciding the site for intraspinal biopsy or shunt tube insertion, 4) establishing the topical relationship between the spinal cord and the tumor, and 5) differentiating neurilemoma from meningoma. Of 10 patients with intramedullary tumors, 5 (50%) were removed, because extirpation was possible when the spinal cord and the tumor were well demarcated on the ultrasonogram. Intratumorous cysts were found to exist in 73% of neurilemoma and 14% of meningioma cases, enabling the differential diagnosis between the two tumors. Intraoperative ultrasonography is an uninvasive method to reveal intradural and extradural conditions and thus constitutes a valuable diagnostic means to ensure safe and precise spinal surgery.     

Intramedullary spinal cord tumour associated with neurofibromatosis type 1

Summary We investigated the characteristic features of intramedullary spinal cord tumour associated with neurofibromatosis type 1 (NF-1). We have experienced 44 cases of pathologically confirmed intramedullary spinal cord tumour. Diagnosis of NF-1 was done according to the criteria set by the National Institute of Health Consensus Development Conference. Within the described population NF-1 was diagnosed in two patients. Both the patients were male and histopathologically the tumours were anaplastic astrocytoma and glioblastoma multiforme respectively. 6 cases of NF-1 associated with intramedullary spinal cord tumour based on the above diagnostic criteria have so far been reported, including our 2 cases. Of these 6 cases, 5 were male and in one sex was not described. The tumour was an astrocytoma in all 6 cases. This finding suggested that intramedullary spinal cord tumour associated with NF-1 tends to occur predominantly in males and that histopathologically the tumour is likely to be an astrocytoma. We conclude that the criteria proposed by the National Institute of Health Consensus Development Conference are contributory in making an accurate pre-operative pathological diagnosis of intramedullary spinal cord tumour associated with NF-1.     

Diagnosis and surgical treatment of spinal hemangioblastoma

Spinal hemangioblastoma is a rare tumor. Its incidence varies from 1.6 to 2.1% of primary spinal cord tumors. In this report, the authors described MRI (magnetic resonance imaging) of spinal hemangioblastoma and its surgical results. [MATERIALS AND METHODS] This series included 10 spinal hemangioblastomas studied with CT or MRI. There were 8 men and 2 women. The age ranged from 21 to 68 years, with a mean age of 45 years. 6 patients were preoperatively and postoperatively studied with a resistive 0.15 T system (Toshiba MRT 15A) or a superconductive 1.5 T system (GE Signa or Siemens Magnetom). The lesions were single in 8 out of 10 patients and multiple in 2. 10 spinal hemangioblastomas were located in intramedullary space and 2 in both intramedullary and extramedullary space. 8 out of 10 patients (80%) were associated with cyst. [RESULTS] (1) MRI In T1-weighted MR images after administration of Gd-DTPA, the solid component of the tumor enhanced brilliantly. The enhanced lesions contained serpiginous areas of signal void, reflecting vascular structures in 5 out of 6 cases. The intrinsic spinal cord signal was heterogenous with low intensity areas representing the associated cyst. The cyst appeared either isointensive to cerebrospinal fluid (CSF) or hyperintense relative to CSF and slightly hypointense relative to the spinal cord. The precise delineation of the tumor was impossible without enhancement. Noncontrast T1-weighted MR images displayed diffuse widening of the spinal cord. On T2-weighted MR images, all regions of the spinal cord enlargement increased in signal. (2) Postoperative results All 10 cases of spinal hemangioblastomas were totally removed with good postoperative results and the associated cysts were drained. The postoperative MRI showed the disappearance of the tumor and significant reduction in the size of the cyst. [CONCLUSION] (1) Gd-DTPA enhanced MRI was useful in defining and outlining the solid component of spinal hemangioblastoma. (2) The complete removal of the tumor with only drainage of the cyst was possible with good postoperative results.     

Advances in diagnosis and treatment of spinal hemangioblastomas

Spinal hemangioblastoma usually leads to large intramedullary cysts. Until recently clinical and conventional radiological examination was often not able to detect single or multiple tumor niduses at the wall of a secondary syringomyelia cyst. Thus during surgical exploration the tumor not infrequently was missed, leading to misinterpretation of the pathological entity as syringomyelia, spinal gliosis or low grade spinal astrocytoma. This often resulted in explorative biopsy or decompressive laminectomy. Clinical deterioration postoperatively was not uncommon due to the remaining tumor and increasing spinal cord enlargement. Now magnetic resonance imaging allows the exact preoperative localization of the medullary lesion apart from the accompanying cysts and facilitates differential diagnosis of primary syringomyelia or other spinal cord neoplasms. Microsurgical techniques and laser-assisted resection have improved the outcome. We report on eight patients with spinal hemangioblastoma treated in our clinic since the installation of magnetic resonance imaging and laser-assisted microneurosurgery.     

Dorsal intramedullary spinal epidermoid cysts: Report of two cases and review of literature

Intramedullary epidermoid cysts of the spinal cord are rare tumors, especially those not associated with spinal dysraphism. About 50 cases have been reported in the literature. Of these, only seven cases have had magnetic resonance imaging (MRI) studies. We report two cases of spinal intramedullary epidermoid cysts with MR imaging. Both were not associated with spina bifida. In one patient, the tumor was located at D4 vertebral level; while in the other, within the conus medullaris. The clinical features, MRI characteristics and surgical treatment of intramedullary epidermoid cyst are presented with relevant review of the literature.     

Intramedullary astrocytoma with granular cell differentiation

Granular cell astrocytomas are uncommon tumors of the central nervous system (CNS) of which no cases have been documented in the spinal cord. This variant of glioma should not be confused with benign granular cell tumor which, although rare, has been well characterized in the spinal cord. We describe here the clinical, pathological, and radiological features of such an astrocytoma arising within the spinal cord at the dorsal level. A 48-year-old female was seen after about 1 year of dorsal pain and gradual spastic paraparesis. Magnetic resonance imaging (MRI) studies showed a 2-cm contrast-enhanced mass in the spinal cord at T6-T7, which had the appearance of an astrocytoma. At surgery, the tumor was found to be infiltrating a posterior column with no dural attachment. It was debulked and dissected. The histological diagnosis was astrocytoma with granular cell differentiation. In addition to documenting a unique example of intramedullary granular cell astrocytoma, we review the literature to investigate differences from other tumors with granular changes described in the spinal cord.     

Intramedullary subependymoma occupying the right half of the thoracic spinal cord--case report

A 37-year-old female presented with a rare spinal subependymoma manifesting as progressive weakness of her right lower extremity over an 8-month period. She had a 10-year history of back pain and urinary disturbance. Magnetic resonance imaging showed diffuse enlargement of the spinal cord from T-2 to T-7 on the T1-weighted images. The enlarged spinal cord was divided into two compartments by a vertical septum-like structure on the T2-weighted images. The tumor occupied the right half of the thoracic spinal cord, and was totally removed through a laminectomy from T-2 to T-7. The histological diagnosis of the resected specimen was subependymoma. Subependymomas are slow-growing tumors usually found in the ventricular system. Spinal subependymomas are difficult to distinguish from other intramedullary spinal tumors based on neuroradiological findings. Subependymomas are surgically curable tumors, so if the tumor is well demarcated and a subependymoma is indicated, an attempt should be made to totally remove the tumor.     

Intradural spinal arachnoid cysts in adults

BACKGROUND: Idiopathic arachnoid cysts are rare lesions not associated with trauma or other inflammatory insults. To date, there have been few large series describing the presentation and management of these lesions. METHODS: Twenty-one cases of intradural spinal arachnoid cysts were identified (1994-2001). Pediatric patients and cases with antecedent trauma were excluded. There were eight women and 13 men with an average age of 52 years. Follow-up averaged 17 months. RESULTS: Cysts were most commonly found in the thoracic spine (81%). Fifteen cysts were dorsal to the spinal cord and six were ventral to the spinal cord. All patients underwent laminectomy with cyst fenestration and radical cyst wall resection. Based upon intraoperative ultrasonography, four cysts were also shunted to the subarachnoid space, and seven patients had an expansile duraplasty with freeze-dried dural allograft. Of the seven patients with syringomyelia, three resolved with extramedullary cyst resection alone. Four required syrinx to subarachnoid shunting. Follow-up MRI demonstrated cyst resolution in all cases. All seven intramedullary syrinxes were decreased in size and four resolved completely. Weakness (100%), hyperreflexia (91%), and incontinence (80%) were more likely to improve than neuropathic pain (44%) and numbness (33%). One patient had increased numbness postoperatively. CONCLUSIONS: Ventral cysts are more likely to cause weakness and myelopathic signs. Preoperative symptoms of neuropathic pain and numbness are less likely to improve than weakness and myelopathy. Utilizing intraoperative ultrasound to guide aggressive surgical treatment with the adjuncts of shunting and duraplasty results in a high rate of cyst and syrinx obliteration.     

The association of hydrocephalus with intramedullary spinal cord tumors: a series of 25 patients

171 patients with intramedullary spinal cord tumors were operated on, of which 25 patients (15%), mostly children, developed symptomatic hydrocephalus. Twenty patients (12%) had malignant tumors, with 13 of the 20 cases (63%) complicated by increased intracranial pressure and ventriculomegaly. Of the remaining 151 patients with benign tumors (89%), only 12 (8%) developed symptomatic hydrocephalus. In an effort to understand the relationship between hydrocephalus and intramedullary spinal cord tumor, the authors analyze the level and histology of the neoplasm, as well as its association with spinal cysts. A review of the neurosurgical literature reveals that 34 similar cases of hydrocephalus associated with intramedullary spinal cord tumors have been reported to date. The authors note that the presence of hydrocephalus in patients with malignant intramedullary astrocytomas is associated with a shorter rate of survival than in those patients with high-grade lesions but without hydrocephalus, apparently due to rapid tumor progression. The ventriculomegaly seen with benign spinal cord gliomas has no statistically significant effect upon long-term prognosis.     

Intracranial metastasis of spinal intramedullary anaplastic astrocytoma

Meningeal spread of spinal intramedullary astrocytoma into the cranium is rare. Only few case reports are available so far in the literature. We report a case of intramedullary high grade astrocytoma of the conus, developing intracranial metastasis after three months of partial excision of the spinal mass. The need for radical surgery, entire neuroaxis radiation, and adjuvant chemotherapy is suggested in the management of malignant spinal cord astrocytoma to prevent dissemination.     

Subependymoma of the cervical spinal cord

A case of subependymoma of the spinal cord in the cervical region is presented. Our experience with this patient and the seven cases of spinal cord subependymoma previously reported show that this tumor predominates in the cervical region and in males (3:1). Although radical removal is considered the rational goal of treatment, larger experience is necessary to know both the rate of growth and prognosis of subependymomas when these tumors arise within the spinal cord.     

Preoperative diagnosis of intramedullary spinal schwannomas

Intramedullary spinal schwannomas are rare benign spinal cord tumors and are easily misdiagnosed because of the imaging characteristics shared with intramedullary glioma. Correct preoperative definitive diagnosis is essential for treatment and prognosis. To improve the preoperative diagnostic strategy, clinical and imaging data of seven patients with intramedullary spinal schwannoma (6 men, mean age 44 years, mean duration of illness 4.2 years) treated in our department between 2003 and 2010 were collected and retrospectively evaluated. The cervical cord was affected in five patients, followed by the thoracic cord in two. All seven cases were misdiagnosed as intramedullary glioma based on the imaging characteristics. Comparison of the clinical features of these 7 patients with those of patients with intramedullary tumors (173 ependymomas and 70 astrocytomas) admitted during the same period revealed significant differences in somatic pain and root pain as the initial symptoms between intramedullary spinal schwannomas and ependymomas (p = 0.005) and between intramedullary spinal schwannomas and astrocytomas (p = 0.019), but not between ependymomas and astrocytomas (p = 0.175). Root or somatic pain as an initial symptom is important for the preoperative diagnosis of intramedullary spinal schwannoma, especially if the imaging characteristics are not entirely specific.     

Spinal intramedullary tumor with exophytic growth

We experienced 22 cases of spinal intramedullary tumor, in which 5 cases were accompanied with exophytic growth. We discussed their clinical and radiological features, and therapeutic problems. Concerning the locations of tumors with exophytic growth, the most common site was conus medullaris, accounting for 60% (3 cases). Histopathological findings were astrocytoma in two cases, and in one case, mixed glioma, ependymoma and hemangioblastoma. In neurological observation, the most common initial symptom was back pain and lumbago, suggesting root pain. No neurological features distinguishable from those of extramedullary tumors were presented. In radiological examination, myelography and CT myelography were very helpful for diagnosis. Myelography and CT myelography showed extramedullary mass, shift and deformity of spinal cord that was not serious as compared with the size of extramedullary mass, and showed the portion where the spinal cord was swollen. Good outcomes were obtained in a case with total removal, and two cases with subtotal and partial removal that were managed with additional irradiation and chemotherapy. However recurrence and intracranial seeding made prognosis poor in two cases where total removal was impossible. We thought that postoperative careful follow-up was necessary not only to detect recurrence but also to detect intracranial seeding in the cases of spinal intramedullary tumor with exophytic growth.     

脊髓髓内肿瘤的显微手术治疗

目的:评估脊髓髓内肿瘤的手术疗效,了解影响预后的因素。方法:回顾分析42例显微手术治疗的髓内肿瘤患者的临床资料,颈髓28例,颈胸交界6例,胸髓5例,圆锥3例。结果:肿瘤全切30例,次全切8例,部分切除4例。无手术死亡。随访3~36个月,病情较术前改善者24例,稳定者13例,加重5例。术前神经功能障碍严重的患者,术后恢复差。3例星形细胞瘤患者术后8~16个月内死亡。结论:脊髓髓内肿瘤在显微镜下大多可手术全切或次全切,并保留正常的脊髓功能,改善或稳定病情。手术应在神经功能加重前进行。恶性胶质瘤的手术效果及预后仍不满意。