Assessing The Role of Intraoperative Neurophysiological Monitoring (IONM) in Preserving Pelvic Floor Integrity During High-Risk Surgeries

Seoyeon Chung; Erica Nah; Muhammad Usaid Ejaz; Samreen Anees; Syed Mohammad Habib; Vikram Ezhil; Marialena Garza; Ibrahim Khan; Faisal R Jahangiri

doi:10.5281/zenodo.15376879

Authors

Seoyeon Chung Global Innervation LLC, Dallas, Texas, USA; School of Medicine, Sungkyunkwan University, Seoul, South Korea https://orcid.org/0009-0001-4854-255X
Erica Nah Global Innervation LLC, Dallas, Texas, USA; Department of Neuroscience, School of Behavioral & Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA https://orcid.org/0009-0003-1210-6873
Muhammad Usaid Ejaz Global Innervation LLC, Dallas, Texas, USA; Alfaisal University, Riyadh, Saudi Arabia https://orcid.org/0009-0000-7348-995X
Samreen Anees Global Innervation LLC, Dallas, Texas, USA; Idaho College of Osteopathic Medicine, Meridian, Idaho, USA https://orcid.org/0009-0008-7632-7276
Syed Mohammad Habib Global Innervation LLC, Dallas, Texas, USA; Sulaiman Al Rajhi University, Al Bukayriyah, Saudi Arabia https://orcid.org/0009-0001-7453-3112
Vikram Ezhil Global Innervation LLC, Dallas, Texas, USA; Paul L. Foster School of Medicine, Texas Tech Health Sciences Center, El Paso, Texas, USA https://orcid.org/0000-0001-9015-6700
Marialena Garza Global Innervation LLC, Dallas, Texas, USA; Department of Neuroscience, School of Behavioral & Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA https://orcid.org/0009-0000-9640-4592
Ibrahim Khan https://orcid.org/0009-0006-4461-4612 https://orcid.org/0009-0006-4461-4612
Faisal R Jahangiri Global Innervation LLC, Dallas, Texas, USA; Department of Neuroscience, School of Behavioral & Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA https://orcid.org/0000-0002-1342-1977

DOI:

https://doi.org/10.5281/zenodo.15376879

Keywords:

Cauda Equina, Tethered Cord Release, Hysterectomy, Colorectal, Urological, External Urinary Sphincters, External Anal Sphincters, Pelvic Floor, multimodality, IONM, SSEP, MEP, EMG, BCR, pudendal, surgery

Abstract

Introduction: Neural injuries during gynecological, urological, colorectal, and spinal surgeries affecting pelvic structures can result in life-altering dysfunction affecting bladder, bowel, and sexual health. Intraoperative neurophysiological monitoring (IONM) is a promising approach to mitigate surgical risks. We hypothesized that IONM could reduce postoperative deficits, maintain pelvic functions, and enhance improvement rates for high-risk procedures.

Methods: A systematic review of databases, including PubMed, ScienceDirect, and Scopus (1965-2024), was conducted per PRISMA guidelines. The IONM search included terms like "external urinary sphincter monitoring," "bladder EMG," "bladder motor evoked potential," "BCR," and "pudendal nerve SSEP." The non-IONM search encompassed keywords such as "hysterectomy," "colorectal surgery," "cauda equina surgeries," and "tethered cord release."

Results: Statistical analysis focused on spinal-related procedures due to insufficient comparative data in urological, colorectal, and gynecological subsections. Analysis included 771 patients, 482 receiving IONM, and 289 without IONM. Chi-square testing showed statistically significant variations in outcome distributions (p < 0.0001 for improvement, baseline maintenance, and deterioration). The odds ratio of 0.32 shows that IONM patients were 68% less likely to improve postoperatively, an unexpected finding requiring interpretation. Odds ratio for baseline function was 4.42, indicating that IONM patients were over four times more likely to maintain baseline function. IONM correlated with a 67% reduction in neurological deterioration risk.

Discussion: Our findings confirm that multimodality IONM is reliable for preserving neural function during high-risk surgeries. Lower improvement rates likely reflect its application in complex cases. Significant literature gaps persist regarding standardized pelvic-specific IONM protocols; future research is necessary.

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Assessing The Role of Intraoperative Neurophysiological Monitoring (IONM) in Preserving Pelvic Floor Integrity During High-Risk Surgeries

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