Upstream Effects: Intraoperative Migration of Intradural Extramedullary Tumor After Non-Adjacent Level Stenosis Decompression

A 74-year-old man with back pain, foot numbness, and hip/thigh radiculopathy was found to have an L1-L2 intradural extramedullary neoplasm and severe L4-L5 stenosis. L4-L5 minimally invasive laminectomy for decompression and concomitant L1-L2 minimally invasive laminectomy for tumor resection were planned. L4-L5 laminectomy was completed first followed by the L1-L2 laminectomy. On extensive intradural exploration at L1-L2, no neoplasm was found. Immediate postoperative imaging showed that the intradural extramedullary tumor had migrated caudally by nearly a complete spinal level, presumably due to changes in cerebrospinal fluid pressure and resultant shift in intradural contents after the L4-L5 laminectomy. Successful resection of the intradural extramedullary tumor was performed, with improvement in the patient's symptoms.

Atypical intradural extramedullary spinal schwannoma causing cauda equina syndrome: A case report and literature review

INTRODUCTION

Spinal schwannomas are slow-growing benign tumors that are generally asymptomatic. However, we describe an atypical case in which an intradural extramedullary schwannoma presented as an acute cauda equina syndrome.

PRESENTATION OF CASE

This was a 58-year-old woman with a 2-month history of severe low back pain and worsening neurological deficits and a 2-day period of acute onset of lower extremity numbness and urinary incontinence. Physical and neurological examination revealed significant lower extremity weakness, tenderness on palpation of the spine, positive straight leg test bilaterally, decreased sensation below the L4 dermatome, reduced sphincter tone, saddle anesthesia, decreased deep tendon reflexes, and loss of sphincter control, consistent with compression of the cauda equina. Magnetic resonance imaging revealed a large mass of heterogeneous composition at the level of L3 lumbar, intruding into the cauda equina. Wide decompression was successfully performed, and histopathological examination confirmed the diagnosis. With rehabilitation, there was some recovery of lower extremity motor function.

DISCUSSION

Spinal schwannomas are rare, accounting for only about 2 % of spinal tumors. Cauda equina syndrome is also rare, with an incidence of 0.08-0.27 % among patients presenting with low back pain. Therefore, it is important for clinicians to have an awareness of the possible association between spinal schwannoma and cauda equina syndrome and to complete a comprehensive assessment of patients with back pain, including magnetic resonance imaging.

CONCLUSION

Early recognition and treatment of a spinal schwannoma causing neurological symptoms can improve patient outcomes.

Endoscopic intradural extramedullary lesion excision: Results of augmented duroplasty with artificial dura

Objectives

Prevailing techniques of dural closure in endoscopic spine surgery (ESS) for intradural extramedullary (IDEM) tumor excision increase the steep learning curve and operative time. We aimed to assess the efficacy of augmented duroplasty with artificial dura and share our initial experience of ESS for IDEM excision.

Materials and Methods

We retrospectively analyzed 18 (n = 18) consecutive patients of IDEM tumors operated by ESS using Destandau's endoscopic system. The pre-operative, post-operative, and at the latest follow-up clinical status were recorded in terms of Nurick's grades and the Oswestry Disability Index. Immediate post-operative complications and intraoperative findings were noted from hospital information system and patient records.

Results

The mean (± SD) age of patients was 40.3 ± 14.9 (range 19-64) years, with M: F ratio of 2:1. All the lesions were intradural and present at lumber (n = 6), thoracic (n = 9), and cervical (n = 3) regions. The average duration of surgery, blood loss, hospital stay, and duration of follow-up were 157 ± 45.3 (90-240) min, 168.8 ± 78.8 (30-300) mL, 4.29 ± 1.4 (2-7) days, and 19.3 ± 7.2 (7-36) months, respectively. There were no CSF leaks, wound-related complications, or material-induced adverse events.

Conclusion

In endoscopic IDEM excision, dural closure with artificial dura is efficient in preventing CSF leak. It shortens the steep learning curve and improves the surgical outcome due to technical ease.

Characteristics and Postoperative Outcomes for High Cervical versus Subaxial Cervical Intradural Extramedullary Tumors: A Multicenter Study

BACKGROUND

High cervical intradural extramedullary tumors are uncommon. Their relationship to surrounding neural structures and vertebral arteries makes surgical excision challenging. No previous studies have compared high cervical to subaxial cervical intradural extramedullary spinal tumors to elucidate their unique characteristics and surgical outcomes.

METHODS

We performed a retrospective study in which patients who underwent excision of a cervical intradural extramedullary tumor were divided into a high cervical group and a subaxial cervical group. Variables included sex, age, Charlson Comorbidity Index, volume, laterality, preoperative weakness, use of neuromonitoring and drains, instrumented fusion, complications, length of stay, histology, discharge location, recurrence, and duration of follow-up. Variables were compared between the 2 groups. Limb power and Nurick classification were charted preoperatively, at discharge, and at 6 months to plot their recovery trajectory.

RESULTS

Eighty-four patients with a total of 90 tumors were enrolled, including 40 patients in the high cervical group and 44 patients in the subaxial spine group. More patients with neurofibromas (P = 0.011) and bilateral tumors (P = 0.044) were in the high cervical group. A greater prevalence of neurofibromatosis type 1 was significant for bilateral high cervical tumors (P = 0.033). More patients in the subaxial group had instrumented fusion (P = 0.045). More patients in the high cervical group had improvement in limb power (P = 0.025) and Nurick classification (P = 0.0001) postoperatively before discharge. By 6 months, both groups had similar recovery. No mortality was attributable to surgery in either group.

CONCLUSION

High cervical intradural extramedullary spine tumors have more bilateral tumors associated with neurofibromatosis type 1. Despite the challenging anatomy, surgical resection is safe with good outcomes in this group.

Laminectomy Versus Laminectomy with Fusion for Intradural Extramedullary Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

The primary objective of our systematic review and meta-analysis was to systematically compare the reported outcomes between laminectomy and laminectomy with fixation/fusion (LF) for the treatment of intradural extramedullary tumors (IDEMTs). Our secondary objective was to compare the outcomes between different laminectomy exposure techniques.

METHODS

PubMed and Embase were queried for literature on laminectomy and LF for IDEMTs. Reports of transforaminal approaches, interlaminar approaches, corpectomy, pediatrics patients, intramedullary tumors, technical studies, animal or cadaver studies, and literature reviews were excluded. The outcome measures recorded were pain, neurologic function, functional independence, cerebrospinal fluid leak, and wound infection. Where possible, the laminectomy technique (partial laminectomy [PL] vs. total laminectomy [TL]) was specified. Stata, version 17, was used for the fixed effects inverse variance meta-analysis.

RESULTS

Of 1849 reports assessed, 17 were included. The meta-analysis revealed that laminectomy (PL or TL) resulted in higher rates of postoperative sagittal instability compared with LF (odds ratio, 1.81; P < 0.001). No differences in any other postoperative outcome were observed between laminectomy and LF (P = 0.44). The systematic review also revealed no differences in postoperative pain, neurologic function, or functional independence or disability between PL and TL. Some evidence suggested that TL might result in greater rates of sagittal instability compared with PL.

CONCLUSIONS

No differences between LF, PL, or TL in pain, neurologic deficit, functional independence, cerebrospinal fluid leak, or wound infection were reported. Laminectomy had greater odds of sagittal instability compared with LF. Patients with preoperative sagittal instability requiring extensive removal of the posterior spinal column to achieve adequate resection of large tumors might benefit from LF.

Poor derivation of Tc-MEP baseline waveforms in surgery for ventral thoracic intradural extramedullary tumor: Efficacy of use of the abductor hallucis in cases with a preoperative non-ambulatory status

Most thoracic intradural extramedullary tumors (IDEMT) are benign lesions that are treated by gross total resection and spinal cord decompression. Intraoperative transcranial-motor evoked potential (Tc-MEP) monitoring is important for reducing postoperative neurological complications. The purpose of this study is to examine the characteristics of Tc-MEP waveforms in surgery for thoracic IDEMT resection based on location of the tumor relative to the spinal cord. The subjects were 56 patients who underwent surgery for thoracic IDEMT from 2010 to 2018. The waveform derivation rate for each lower muscle was examined at baseline and intraoperatively. 56 patients had a mean age of 61.7 years, and 21 (38%) were non-ambulatory before surgery. The tumors were schwannoma (n = 28, 50%), meningioma (n = 25, 45%), and neurofibroma (n = 3, 5%); and the lesions were dorsal (n = 29, 53%) and ventral (n = 27, 47%). There was a significantly higher rate of undetectable waveforms in all lower limb muscles in the ventral group compared to the dorsal group (15% vs. 3%, p < 0.05). In non-ambulatory cases, the derivation rate at baseline was significantly lower for ventral thoracic IDMETs (47% vs. 68%, p < 0.05). The abductor hallucis (AH) had the highest waveform derivation rate of all lower limb muscles in non-ambulatory cases with a ventral thoracic IDMET. Spinal cord compression by a ventral lesion may be increased, and this may be reflected in greater waveform deterioration. Of all lower limb muscles, the AH had the highest derivation rate, even in non-ambulatory cases with a ventral IDEMT, which suggests the efficacy of multichannel monitoring including the AH.

Intradural Extramedullary Primary Ependymoma of the Craniocervical Junction Combined with C1 Partial Agenesis: Case Report and Review of the Literature

BACKGROUND

Intramedullary ependymomas represent 40%-60% of spinal cord tumors in adults and can be located along the entire spinal cord. Intradural extramedullary (IDEM) ependymomas are very rare with the exception of tumors located at the filum terminale or conus medullaris, with histologic features of myxopapillary ependymomas (World Health Organization grade I).

CASE DESCRIPTION

We present the case of a 42-year-old woman with an IDEM ependymoma of the craniocervical junction who experienced neck pain for 5 months. Magnetic resonance imaging of the cervical spine and craniocervical junction showed a large IDEM solid-cystic lesion with anterolateral junction spinal cord compression. A preoperative computed tomography scan did not show any calcified lesion, although a partial agenesis of the C1 posterior arch was observed. During surgery, a well-encapsulated IDEM tumor without dural attachment or medullary infiltration was found, and a total en bloc excision was performed. Histologic examination revealed a grade II ependymoma. The patient had an excellent clinical recovery, with no recurrence after 2 years of follow-up.

CONCLUSIONS

To the best of our knowledge, no other cases of craniocervical junction ependymomas with vertebral bone abnormalities are described in the literature. This association supports the hypothesis that these lesions may originate from the extrusion of ependymal cells before neural tube closure. Differential diagnosis should include other extramedullary tumors that are more frequent in this region, such as meningioma, schwannoma, or dermoid tumor.

Granular cell tumor of the intradural extramedullary spinal cord : report of two cases with respect to radiological differential diagnosis

Granular cell tumors (GrCTs) of the spinal cord are rare benign tumors with a high rate of local recurrence. Only 6 cases of spinal GrCTs have been reported. GrCT is difficult to distinguish from other benign tumors such as schwannoma using imaging. A radiological "speckled dots" sign may be a useful differentiating feature of GrCT based upon experience with two cases and a review of the literature.

Intradural extramedullary ependymoma with spinal root attachment: a case report

A 36-year-old female patient presented with shoulder pain experienced over a period of one year and progressive weakness in both legs for one month. A magnetic resonance imaging scan revealed an intradural extramedullary (IDEM) fusiform mass about 9.8 cm in length, heterogeneously enhanced at the level of C6-T4 with spinal cord compression. At the time of surgery, the surgeon found an encapsulated IDEM tumor with spinal root attachment. The tumor was completely resected and the histologic diagnosis revealed ependymoma. The patient showed a favorable outcome with no recurrence at the 6-month follow-up. This paper reports a rare case of intradural extramedullary ependymoma with spinal root attachment.

Capillary hemangioma of the thoracic spinal cord

Capillary hemangiomas are common soft tissue tumors on the skin or mucosa of the head and neck in the early childhood, but very rare in the neuraxis. A 47-year-old man presented with one month history of back pain on the lower thoracic area, radiating pain to both legs, and hypesthesia below T7 dermatome. Thoracic spine MRI showed 1×1.3×1.5 cm, well-defined intradural mass at T6-7 disc space level, which showed isointensity to spinal cord on T1, heterogeneous isointensity on T2-weighted images, and homogeneous strong enhancement. The patient underwent T6-7 total laminotomy, complete tumor removal and laminoplasty. Histologically, the mass showed a capsulated nodular lesion composed of capillary-sized vascular channels, which were tightly packed into nodules separated by fibrous septa. These features were consistent with capillary hemangioma.

The surgical treatment for spinal intradural extramedullary tumors

Background

We wanted to investigate the results of surgical treatment and analyze the factors that have an influence on the neurologic symptoms and prognosis of spinal intradural extramedullary (IDEM) tumors.

Methods

The spinal IDEM tumor patients (11 cases) who had been treated by surgical excision and who were followed up more than 1 year were retrospectively analyzed. Pain was evaluated by the visual analogue scale (VAS) and the neurologic function was assessed by Nurick's grade. The pathological diagnosis, the preoperative symptom duration, the tumor location on the sagittal and axial planes and the percentage of tumor occupying the intradural space were investigated. In addition, all these factors were analyzed in relation to the degree of the preoperative symptoms and the prognosis. On the last follow-up, the MRI was checked to evaluate whether or not the tumor had recurred.

Results

The most common diagnosis was schwannomas (73%), followed by meningiomas (18%). The percentage of tumor occupying the intradural space was 82.9 ± 9.4%. The VAS score was reduced in all cases from 8.0 ± 1.2 to 1.2 ± 0.8 (p = 0.003) and the Nurick's grade was improved in all cases from 3.0 ± 1.3 to 1.0 ± 0.0 (p = 0.005). The preoperative symptoms were correlated with only the percentage of tumor occupying the intradural space (VAS; r² = 0.75, p = 0.010, Nurick's grade; r² = 0.69, p = 0.019). One case of schwannoma recurred.

Conclusions

The degree of neurologic symptoms was correlated with the percentage of tumor occupying the intradural space. All the tumors were able to be excised through the posterior approach. The postoperative neurologic recovery was excellent in all the cases regardless of any condition. Therefore, aggressive surgical excision is recommended even for cases with a long duration of symptoms or a severe neurologic deficit.