Recapping T-saw laminocostotransversoplasty for ventral meningiomas in the thoracic region

Novel Dural-Splitting Operative Technique for Excision of Ventrally Located Spinal Meningiomas

OBJECTIVE

Spinal meningiomas are one of the frequently seen intradural extramedullary spinal tumors. They are almost always World Health Organization grade I, and a complete removal of the tumor can be curative. However, ventrally located spinal meningioma removal can be challenging due to the position in front of the spinal cord through a narrow corridor provided by routine dorsal approaches. Incomplete excision of the relatively inaccessible dural attachment can consequently lead to recurrence. We describe a safe and reproducible technique used to achieve Simpson grade I removal of ventrally located spinal meningioma.

METHODS

Since the spinal dura can be easily divided into inner and outer layers and the tumor usually spares the outer layer, we developed a simple technique to achieve total resection of the tumor and involved dura while leaving the outer dural layer intact.

RESULTS

An advantage of this procedure is that it exploits an interdural approach to allow early devascularization of the tumor without cord manipulation and provides access to the ventral dura to achieve Simpson grade I excision. Another advantage is complete dural closure to minimize postoperative cerebrospinal fluid leak or ventral cord herniation without the need for dural substitutes.

CONCLUSION

Its novel interdural approach can be used for all ages and all spinal meningiomas.

Low recurrence after Simpson grade II resection of spinal benign meningiomas in a single-institute 10-year retrospective study

The objective of this study was to more fully understand the optimal neurosurgical strategy for spinal benign meningiomas from a medium to long-term perspective. This retrospective study included a cohort of 35 patients with a diagnosis of spinal meningioma who were first operated at our institute over the past 10 years and followed-up for at least 2 years after surgery. The inclusion criterion for the study was the pathological diagnosis finally verified as benign meningioma of World Health Organization (WHO) grade 1. The average follow-up duration after surgery was 61.0 months. The location of the spinal meningioma was classified into ventral or dorsal type based on the operative video record and the preoperative MR images. The extent of resection of the spinal meningioma was carefully determined based on the Simpson grade. The average neurological condition was significantly improved at the final follow-up. Simpson grade I or II resection was achieved in 31 of 35 cases (88.6%). No Simpson grade I or II cases showed local recurrence during follow-up. Tumor recurrence was noted in 2 of 4 cases of Simpson grade IV resection. One case has been followed-up without any re-operation because of no neurological deterioration, and the other case underwent stereotactic radiosurgery. This study suggested that meticulous Simpson grade II resection of spinal benign meningiomas of WHO grade 1 may be good enough from a medium to long-term follow-up perspective, though longer follow-up is absolutely necessary.

Combined Transpedicular-Transarticular Approach for Ventrally Located Thoracic Intradural Meningiomas

Background

The ventrally located intradural meningiomas in the thoracic spine are still considered a challenge for all spine surgeons. Many surgical approaches were developed to excise the lesion without violating the neural structures. They differ in their invasiveness, safety, and efficacy. One of these approaches is the postero-lateral combined transpedicular-transarticular approach (TPA-TAA).

Patients and Methods

From January 2016 to December 2018, all patients with ventrally located thoracic meningiomas were operated on using the combined TPA-TAA. We evaluated all the patients preoperatively, immediate postoperative, and 6 months later. Clinical and functional outcomes were assessed using the muscle strength grade and the Nurick grading system. Magnetic resonance imaging was obtained for all patients postoperative and at 6 months later.

Results

After 6 months, all patients experienced clinical and functional improvement. The mean muscle strength grade rose from 3.8 preoperatively to 4.8 after 6 months. According to the Nurick grading system, the mean preoperative grade was 4.4 and dropped to 1.8 after 6 months. Minor transient complications such as superficial wound infection and the cerebrospinal fluid leak were observed in 1 patient for each. Gross total tumor excision was achieved in all patients. No cases of tumor recurrence were noted during the follow-up period.

Conclusions

This combined TPA-TAA is considered a safe and effective approach in excising ventrally located intradural thoracic meningiomas with minimal postoperative morbidities.

Successful treatment of a diffuse type tenosynovial giant cell tumor in the thoracic spine mimicking spinal metastasis by frozen recapping laminoplasty in a patient with thyroid cancer

PURPOSE

Tenosynovial giant cell tumor of the diffuse type (TGCT-D) involving the spine is rare. Its differential diagnosis includes metastatic disease; however, there have been few reports of spinal TGCT-D mimicking spinal metastasis in patients with a history of malignancy.

METHODS

We report on a 35-year-old woman with a history of papillary thyroid cancer who was diagnosed with TGCT-D of the thoracic spine mimicking spinal metastasis. Preoperative computed tomography (CT) revealed a 1.0 × 1.0-cm lytic bone lesion involving the left T7 vertebral lamina, pedicle, and the T6-7 facet joint; the thoracic spine lesion was markedly fluorodeoxyglucose-avid on positron-emission tomography/computed tomography (PET/CT).

RESULTS

Spinal metastasis was initially suspected given the patient's history of papillary thyroid cancer. Total excision was performed with recapping laminoplasty. The resected lamina was frozen in liquid nitrogen and used as a frozen autograft (frozen recapping laminoplasty) for spinal reconstruction with posterior instrumentation. Histological findings supported a diagnosis of TGCT-D. The patient had no evidence of local recurrence 2 years post-surgery. Bone union was achieved 3 years post-surgery.

CONCLUSIONS

TGCT-D can mimic metastasis in PET/CT and should be included in the differential diagnosis if a lytic lesion affecting the posterior elements of the vertebrae involves the facet joints. CT-guided biopsy is recommended for accurate diagnosis when an occult tumor, such as TGCT, is incidentally detected on PET-CT, even in patients with a history of malignant neoplasm. Frozen recapping laminoplasty is useful for complete resection of a spinal tumor, preventing local recurrence, and preservation of the posterior spinal elements.

Posterolateral approach for spinal intradural meningioma with ventral attachment

Background:

Spinal meningioma with ventral attachment is a challenging pathology. Several technical modifications have been proposed to secure safe and precise resection of these tumors.

Materials and Methods:

This retrospective study focused on the precise and safe surgery of spinal meningiomas with strictly ventral attachment of cervical or thoracic spine. The surgical technique included a lateral oblique position for the patient, laminectomy with unilateral medial facetectomy on the tumor side, and spinal cord rotation with the dentate ligament. The neurological status of patients was assessed using the modified McCormick functional schema (mMFS) and sensory pain scale (SPS) before and at least 3 months after surgery. Patients were followed-up for a mean of 23.7 months. Tumor removal was graded using the Simpson grade for removal of meningiomas, and the extent of excision was confirmed using early postoperative magnetic resonance imaging.

Results:

Simpson grade 1 or 2 resections were achieved in all cases. No major surgery-related complications were encountered, postoperatively. The mean mMFS score before surgery was 3.1, improving significantly to 1.7 after surgery (P < 0.05). The mean SPS score before surgery was 2.4, improving significantly to 1.6 after surgery (P < 0.05).

Conclusions:

This surgical technique offers a posterolateral surgical corridor to the ventral canal of both cervical and thoracic spine. The present preliminary analysis suggests that functional outcomes were satisfactory with minimal surgery-related complications, although considerable surgical experience is needed to achieve a high level of surgical confidence.

En-bloc resection of thoracic calcified meningioma with inner dural layer in recapping T-saw laminoplasty: a case report

Background

In the treatment of spinal cord tumors, complete tumor resection with complete reconstruction of the spine represents the ideal goal. However, for the treatment of heavily calcified spinal meningioma, en-bloc resection of the tumor together with the involved dura at the tumor base through laminectomy is quite difficult. Conventional laminectomy is not wide enough to allow full exposure of such tumors, and postoperative dural defects can cause serious complications.

Case presentation

A 58-year-old Japanese woman presented with a 3-month history of progressive muscle weakness and numbness of the lower extremities. Magnetic resonance imaging (MRI) and computed tomography showed a calcified spinal cord tumor with dural tail sign at the T10-T11 level, severely compressing the spinal cord anterolaterally. The patient underwent en-bloc resection of the tumor with the inner layer of the dura and preservation of the outer layer of the dura through recapping T-saw laminoplasty of T10-T11, including bilateral facet joints. The tumor was histologically diagnosed as meningioma. Postoperatively, the patient achieved complete recovery of neurological functions. Bone union after laminoplasty was obtained within 6 months. Follow-up MRI at 5 years postoperatively demonstrated no recurrence of the tumor.

Conclusion

Resection of spinal meningioma with only the inner layer of dura can minimize postoperative complications, including spinal fluid leakage. Recapping T-saw laminoplasty provides extensive exposure for tumor removal. The combination of these techniques may offer an ideal surgical option for complete resection of spinal meningioma with complete preservation of the posterior spinal elements.

Huge thoracolumbar extradural arachnoid cyst excised by recapping T-saw laminoplasty

BACKGROUND CONTEXT

Spinal extradural arachnoid cysts are rare expanding lesions in the spinal canal. Total removal of the cyst and repair of the dural defect is the primary treatment for symptomatic spinal extradural arachnoid cysts.

PURPOSE

To report the usefulness of recapping T-saw laminoplasty in treating huge extradural arachnoid cyst.

STUDY DESIGN

Case report.

METHODS

We report the case of a 43-year-old man who presented with a 2-year history of progressive muscle weakness and numbness of the lower extremities. Magnetic resonance imaging (MRI) showed a huge extradural arachnoid cyst at the T12-L3 level extending into bilateral neural foramina and severe posterior compression of the spinal cord and cauda equina.

RESULTS

The patient underwent total resection of the cyst and closure of the communication. En bloc recapping T-saw laminoplasty of T12-L2 including the T12-L1 and L1-L2 facet joints was performed to obtain extensive exposure and preserve posterior stability. Postoperatively, the patient achieved complete recovery of neurologic functions. Follow-up MRI demonstrated no recurrence of the cyst. Bone union after laminoplasty was obtained within 6 months.

CONCLUSION

Total resection of the cyst and closure of the communication is curative for this rare lesion. Recapping T-saw laminoplasty provides extensive exposure for removal of a large cyst while allowing complete preservation of the posterior spinal elements.