Are Posterior Column Deficits Inevitable in Intramedullary Tumor Resection?

Wednesday, February 21, 2024

Presenting Author(s)

Hani Chanbour, MD

Spine fellow
Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN
Nashville, TN, US

Co-Author(s)

AA

Amir Abtahi, MD

orthopedic surgeon
Department of Orthopedic Surgery, Vanderbilt University Medi, United States
SJ

Soren Jonzzon, MD

resident
Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN
Nashville, TN, US
David Liles, MD

Resident
Vanderbilt University Medical Center
Nashville, TN, US
AP

Ambika Paulson, MD

researcher
Department of Orthopedic Surgery, Vanderbilt University Medi, United States
BS

Byron Stephens, MD

orthopedic surgeon
Vanderbilt University School of Medicine, United States
Iyan Younus, MD

resident
Vanderbilt University Medical Center
Nashville, TN, US
Omar Zakieh, MD

Spine fellow
Vanderbilt University Medical Center
Scott L. Zuckerman, MD, MPH (he/him/his)

Assistant Professor of Neurological Surgery
Vanderbilt University Medical Center
Nashville, Tennessee, United States

Disclosure(s):

Hani Chanbour, MD: No financial relationships to disclose

Soren Jonzzon, MD: No financial relationships to disclose

David Liles, MD: No financial relationships to disclose

Omar Zakieh, MD: No financial relationships to disclose

Introduction: Whether a posterior myelotomy for intramedullary spinal removal is always associated with a posterior column deficit remains unknown. In patients undergoing posterior intramedullary tumor resection, we sought to: 1) report the rate of new posterior column deficit and overall neurological deficit, and 2) determine the risk factors of postoperative neurological deficits.

Methods: A single-institution retrospective cohort study of patients undergoing posterior intramedullary tumor resection was performed from 2010-2020. Both primary/metastatic tumors were included. Tumors below L2 were excluded. Primary outcome was the onset of new posterior column deficit, defined as new numbness and/or balance problems. Secondary outcomes included overall neurological deficit.

Results: Of 40 patients undergoing intramedullary tumor resection, 36(90.0%) were primary and 4(10.0%) were metastatic. Histology was: 21(52.5%) ependymoma, 4(10.0%) astrocytoma, 1(2.5%) hemangioblastoma, and 14(35.0%) others. Tumors were mostly thoracic (35.0%) and located central to the cord (62.5%). Myelotomy was performed in 21(52.5%), and complete resection was performed in 23(57.5%). New posterior column deficit occurred in 22(55.0%), and among myelotomy patients, 13/21(61.9%) had new posterior column deficits (p=0.525). Overall new neurological deficit occurred in 33(82.5%), and 23/33(57.5%) had a worsening of their motor function. Among these patients, 6/23(26.0%) lost the ability to ambulate and 11/23(47.8%) had a significant decline of at least 2 motor grades. New bowel/bladder dysfunction was seen in 6(15.0%). No significance was found between posterior column deficit and the presence of cord edema (p>0.999), spine segment (p=0.337), central/peripheral location (p=0.176), complete resection (p=0.200), tumor type/size (p=0.310,p=0.362), and blood loss/operative time (p=0.568,p=0.869). Similarly, no difference was found between the above-mentioned factors and overall neurological deficit (all >0.05).

Conclusion : Of patients undergoing myelotomy, 62% had new posterior column deficits. A very high rate of new neurologic deficits was seen at 82.5%. These results highlight the significant risk involved in intramedullary tumor surgery and the importance of patient counseling.