Diffusion tensor tractography for the surgical management of peripheral nerve sheath tumors

OBJECT Peripheral nerve sheath tumors (PNSTs) are uncommon but bear a significant risk of malignancy. High-resolution MRI is the standard technique for characterizing PNSTs. However, planning the appropriate extent of resection and subsequent reconstructive strategies is highly dependent on the intraoperative findings because preoperative MRI evaluation can be insufficient. Diffusion tensor tractography (DTT) represents a recently developed advanced MRI technique that reveals the microstructure of tissues based on monitoring the random movement of water molecules. DTT has the potential to provide diagnostic insights beyond conventional MRI techniques due to its mapping of specific fibrillar nerve structures. Here, DTT was applied to evaluate PNSTs and to examine the usefulness of this method for the correct delineation of tumor and healthy nerve tissue and the value of this information in the preoperative planning of surgical interventions. METHODS In this prospective study, patients with the clinical symptoms of a PNST were investigated using DTT 3-Tesla MRI scans. Image data processing and tractography were performed using the FACT (fiber assessment by continuous tracking) algorithm and multiple-regions-of-interest approach. The surgical findings were then compared with the results of the DTT MRI scans. Preoperative fascicle visualization and the correlation with the intraoperative findings were graded. RESULTS In a 21-month period, 12 patients with PNSTs were investigated (7 female and 5 male patients with a mean age of 46.2 ± 19.2 years). All patients underwent surgical removal of the tumor. Schwannoma was the most common benign histopathological finding (n = 7), whereas 2 malignant lesions were detected. In 10 of 12 patients, good preoperative nerve fascicle visualization was achieved using DTT scans. In 9 of 10 patients with good preoperative fascicle visualization, good intraoperative correlation between the DTT scans and surgical anatomy was found. CONCLUSIONS DTT properly visualizes the peripheral nerve fascicles and their correct anatomical relation to PNST. DTT represents a promising new method for the preinterventional planning of nerve tumor resection.

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Malignant peripheral nerve sheath tumors in the setting of segmental neurofibromatosis

Journal of Neurosurgery ◽

10.3171/jns.2000.92.2.0342 ◽

2000 ◽

Vol 92 (2) ◽

pp. 342-346 ◽

Cited By ~ 32

Author(s):

Jacob Schwarz ◽

Allan J. Belzberg

Keyword(s):

Peripheral Nerve ◽

Neurological Impairment ◽

Malignant Degeneration ◽

Surgical Removal ◽

Surgical Indications ◽

Content Type ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Sheath ◽

Adjacent Structures

✓ Approximately 100 cases of segmental neurofibromatosis (NF5) have been reported in the recent literature. Patients with NF5 present with café-au-lait macules, freckles, and/or neurofibromas limited to one or adjacent dermatomes. Neurofibromas arising in NF5 have been uniformly considered to be benign; patients were thought to have an excellent prognosis without the risk of developing malignant peripheral nerve sheath tumors (PNSTs), which are characteristic in patients with the generalized form of this disease, von Recklinghausen's NF. In this report the authors detail the first observations of malignant PNSTs in two patients with NF5. Indications for surgical removal of a neurofibroma in a patient with NF include pain, neurological impairment, compression of adjacent structures, cosmetic disfigurement, and rapid tumor growth suggestive of malignant degeneration. Surgical indications are similar for patients with NF5. All patients with neurofibromas should be considered at risk for malignant degeneration.

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Diffusion tensor imaging and tractography for preoperative assessment of benign peripheral nerve sheath tumors

European Journal of Radiology ◽

10.1016/j.ejrad.2020.109110 ◽

2020 ◽

Vol 129 ◽

pp. 109110 ◽

Cited By ~ 1

Author(s):

Alexandra S. Gersing ◽

Barbara Cervantes ◽

Carolin Knebel ◽

Benedikt J. Schwaiger ◽

Jan S. Kirschke ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Peripheral Nerve ◽

Diffusion Tensor ◽

Preoperative Assessment ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Sheath

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Fluorescein-guided removal of peripheral nerve sheath tumors: a preliminary analysis of 20 cases

Journal of Neurosurgery ◽

10.3171/2019.9.jns19970 ◽

2019 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Ignazio G. Vetrano ◽

Francesco Acerbi ◽

Jacopo Falco ◽

Grazia Devigili ◽

Sara Rinaldo ◽

...

Keyword(s):

Peripheral Nerve ◽

Tumor Resection ◽

Gross Total Resection ◽

Light Illumination ◽

Total Resection ◽

Follicular Hyperplasia ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Sheath ◽

Yellow 560

OBJECTIVEBenign peripheral nerve sheath tumors (PNSTs) include mainly schwannomas—the most common tumors arising from peripheral nerves—and neurofibromas. Due to their origin, distinguishing between functional intact nerve and the fibers from whence the PNST arose may not always be easy to perform. The introduction of intraoperative tools to better visualize these tumors could be helpful in achieving a gross-total resection. In this study, the authors present a series of patients harboring PNST in which the surgery was performed under fluorescein guidance.METHODSBetween September 2018 and February 2019, 20 consecutive patients with a total of 25 suspected PNSTs underwent fluorescein-guided surgery performed under microscopic view with a dedicated filter integrated into the surgical microscope (YELLOW 560) and with intraoperative monitoring. All patients presented with a different degree of contrast enhancement at preoperative MRI. Fluorescein was intravenously injected after intubation at a dose of 1 mg/kg. Preoperative clinical and radiological data, intraoperative fluorescein characteristics, and postoperative neurological and radiological outcomes were collected and analyzed.RESULTSSix patients were affected by neurofibromatosis or schwannomatosis. There were 14 schwannomas, 8 neurofibromas, 1 myxoma, 1 reactive follicular hyperplasia, and 1 giant cell tumor of tendon sheath. No patient experienced worsening of neurological status after surgery. No side effects related to fluorescein injection were found in this series. Fluorescein allowed an optimal intraoperative distinction between tumor and surrounding nerves in 13 of 14 schwannomas and in all neurofibromas. In 6 neurofibromas and in 1 schwannoma, the final YELLOW 560 visualization showed the presence of small tumor remnants that were not visible under white-light illumination and that could be removed, obtaining a gross-total resection.CONCLUSIONSFluorescein was demonstrated to be a feasible, safe, and helpful intraoperative adjunct to better identify and distinguish PNSTs from intact functional nerves, with a possible impact on tumor resection, particularly in diffuse neurofibromas.

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Go for the Gold: A “Plane” and Simple Technique for Resecting Benign Peripheral Nerve Sheath Tumors

Operative Neurosurgery ◽

10.1093/ons/opz034 ◽

2019 ◽

Vol 18 (1) ◽

pp. 60-68 ◽

Cited By ~ 8

Author(s):

Jonathan J Stone ◽

Robert J Spinner

Keyword(s):

Peripheral Nerve ◽

Tumor Resection ◽

Layer By Layer ◽

Nerve Sheath Tumor ◽

Neurological Outcomes ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Tumor ◽

Nerve Sheath ◽

Yellow Color

Abstract BACKGROUND Intraneural dissection is a useful technique for achieving gross total resection and preserving functional fascicles for peripheral nerve tumors. Finding the correct tissue plane is the critical step for safe successful enucleation. The authors hypothesized that the yellow color of benign nerve tumors can be used to identify surgical planes. OBJECTIVE To describe a technique to find the correct intraneural dissection plane based on a quantified yellow appearance during resection of benign peripheral nerve sheath tumors. METHODS Intraoperative photographs were reviewed to determine the percentage of yellow that tumors appeared at different phases of surgery. A technique was developed to quantitatively measure the amount of yellow using Photoshop. Previously published journal articles containing color images of peripheral nerve tumor resections were also analyzed for yellow tumor color. RESULTS There were 24 patients with suitable images to permit measurement of color for 3 steps of the procedure. The average percentages of yellow for tumor exposure, tumor resection, and removed specimen were 36.5%, 59.1%, and 80.4%, respectively (P < .001). Three publications were found that contained high-quality images of at least 2 phases of the surgery with average yellow content of 47.4% and 84% (P < .01). CONCLUSION The simple observation that a benign nerve sheath tumor is yellow in color can be used to guide surgical resection and achieve excellent outcomes. Intraneural dissection through the pseudocapsule should be pursued layer by layer until a yellow true capsule is found. By sparing functional nervous tissue within the pseudocapsule, this technique may lead to improved neurological outcomes.

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DIAGNOSIS AND MANAGEMENT OF INTRACRANIAL MALIGNANT PERIPHERAL NERVE SHEATH TUMORS

Neurosurgery ◽

10.1227/01.neu.0000318167.97966.f3 ◽

2008 ◽

Vol 62 (4) ◽

pp. 825-832 ◽

Cited By ~ 22

Author(s):

Liang Chen ◽

Ying Mao ◽

Hong Chen ◽

Liang-Fu Zhou

Keyword(s):

Peripheral Nerve ◽

Tumor Resection ◽

Residual Tumor ◽

The Other ◽

Postoperative Survival ◽

Rational Approach ◽

General Strategy ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Sheath

Abstract OBJECTIVE Intracranial malignant peripheral nerve sheath tumors (MPNSTs) are rare and generally carry a poor prognosis. We have analyzed our experience with MPNSTs and conducted a review of the literature in an attempt to identify a rational approach to the management of these tumors. METHODS Eight patients underwent surgical treatment for intracranial MPNSTs during a 10-year period from 1996 to 2005. The general strategy was to perform complete resection whenever possible and to provide adjuvant radiotherapy for residual tumor. Chemotherapy was not used in this group. The clinical, radiological, operative, and pathological findings of the patients were reviewed retrospectively. RESULTS Six of the eight patients underwent primary operations; two of the eight patients had previously undergone other transcranial surgery operations. Total tumor resection was achieved in five patients. At this time, two have been recurrence-free for 3.5 and 5 years, respectively, and the other three patients had a mean postoperative survival of 7 months. There was one case of near total (>90%) and two cases of partial (<90%) tumor removal; the postoperative survival rate was 4, 4, and 2 months, respectively. Only two patients in our group accepted radiotherapy after surgery; one survived only 4 months and the other has been recurrence-free for 5 years. CONCLUSION MPNSTs are fast-growing, invasive tumors with rather unsatisfactory outcomes. Total surgical resection seems to be the most effective therapeutic method, and radiotherapy may play a role in local control.

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Diffusion-weighted imaging and diffusion tensor imaging as adjuncts to conventional MRI for the diagnosis and management of peripheral nerve sheath tumors: current perspectives and future directions

European Radiology ◽

10.1007/s00330-018-5838-8 ◽

2018 ◽

Vol 29 (8) ◽

pp. 4123-4132 ◽

Cited By ~ 9

Author(s):

Alexander T. Mazal ◽

Oganes Ashikyan ◽

Jonathan Cheng ◽

Lu Q. Le ◽

Avneesh Chhabra

Keyword(s):

Diffusion Tensor Imaging ◽

Peripheral Nerve ◽

Diffusion Weighted Imaging ◽

Diffusion Tensor ◽

Future Directions ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Conventional Mri ◽

Nerve Sheath ◽

And Diffusion

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Surgical management of malignant peripheral nerve sheath tumors

Neurosurgical FOCUS ◽

10.3171/foc.2007.22.6.14 ◽

2007 ◽

Vol 22 (6) ◽

pp. 1-8 ◽

Cited By ~ 20

Author(s):

John Gachiani ◽

Daniel Kim ◽

Adriane Nelson ◽

David Kline

Keyword(s):

Soft Tissue ◽

Peripheral Nerve ◽

Surgical Techniques ◽

Soft Tissue Sarcomas ◽

Neurofibromatosis Type ◽

Surgical Removal ◽

Complete Excision ◽

Nerve Sheath Tumors ◽

Peripheral Nerve Sheath Tumors ◽

Nerve Sheath

Object The aim of this study was to describe the presentation of patients harboring soft tissue sarcomas involving the nerves, most of which were malignant peripheral nerve sheath tumors (MPNSTs), and provide an algorithm for their treatment. Methods The authors retrospectively analyzed data on 43 surgically treated soft tissue sarcomas involving the nerves, 34 (79%) of which were MPNSTs. Tumor classifications are presented, together with patient numbers, locations of MPNSTs, surgical techniques, and adjunctive treatments. Results The 34 MPNSTs were surgically treated during a period of 40 years. Most of these lesions (19 MPNSTs [56%]) were located in the brachial plexus, whereas the rest were located on other major nerves. Neurofibromatosis Type 1–associated tumors (12 lesions) represented 35% of the total number of MPNSTs. Although the main goal of surgery was complete excision, it was successful in only 16 patients (47%). Of the available records, 18 patients (53%) died due to disease progression. Conclusions Malignant peripheral nerve sheath tumors are rare. Surgical removal with margins when possible coupled by adjuvant radiotherapy offers the best chance of survival. The role of chemotherapy is still being defined.

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