Dr. Jahangiri's Publications

Research and Publications in Neurophysiology

Paper

ArtifactGen: Benchmarking WGAN-GP vs Diffusion for Label-Aware EEG Artifact Synthesis

2025

Arasu, H., & Jahangiri, F. R. (2025). ArtifactGen: Benchmarking WGAN-GP vs Diffusion for Label-Aware EEG Artifact Synthesis. arXiv preprint arXiv:2509.08188.

Paper

StableSleep: Source-Free Test-Time Adaptation for Sleep Staging with Lightweight Safety Rails

2025

Arasu, Hritik, and Faisal R. Jahangiri. "StableSleep: Source-Free Test-Time Adaptation for Sleep Staging with Lightweight Safety Rails." arXiv preprint arXiv:2509.0298v1 (2025).

Paper

Focused Ultrasound for Movement Disorders: Evidence from a Systematic Review of Efficacy and Safety

2025

Brown, C., Shaik, R., Arasu, H., & Jahangiri, F. R. (2025). Focused Ultrasound for Movement Disorders: Evidence from a Systematic Review of Efficacy and Safety. J of Neurophysiological Monitoring, 3(3), 21–29. https://doi.org/10.5281/zenodo.16933232

Paper

Evaluating Neurological Outcomes in Neonates Through SSEP: A Review of Current Evidence

2025

Siddiqui, E. R., Ayyoub, S. M., Parapperi, R., Isa, U. J., Mohammad, J., Mohammad Habib, S., Memon, U., & Jahangiri, F. R. (2025). Evaluating Neurological Outcomes in Neonates Through SSEP: A Review of Current Evidence. J of Neurophysiological Monitoring, 3(3), 9–20. https://doi.org/10.5281/zenodo.16923257

Paper

Wired for Relief: Assessing the Risks and Rewards of DBS in Treatment-Resistant Obsessive Compulsive Disorder

2025

Nataraja, V., Ravindran, J., Steelman, A., Turner, J. F., & Jahangiri, F. R. (2025). Wired for Relief: Assessing the Risks and Rewards of DBS in Treatment-Resistant Obsessive Compulsive Disorder. J of Neurophysiological Monitoring, 3(2), 88–100. https://doi.org/10.5281/zenodo.16222883

Paper

The Mapping of the Sensory Circuits in the Spinal Cord: A Literature Review

2025

Mohammed, A., Brown, C., Aziz, H., Franca, A., & Jahangiri, F. R. (2025). The Mapping of the Sensory Circuits in the Spinal Cord: A Literature Review. J of Neurophysiological Monitoring, 3(2), 69–87. https://doi.org/10.5281/zenodo.15542995

Paper

Assessing The Role of IONM in Preserving Pelvic Floor Integrity During High-Risk Surgeries

2025

Chung, S., Nah, E., Ejaz, M. U., Anees, S., Mohammad Habib, S., Ezhil, V., Garza, M., Khan, I., & Jahangiri, F. R. (2025). Assessing The Role of Intraoperative Neurophysiological Monitoring (IONM) in Preserving Pelvic Floor Integrity During High-Risk Surgeries. J of Neurophysiological Monitoring, 3(2), 31–68. https://doi.org/10.5281/zenodo.15376879

Paper

Motor Evoked Potential Monitoring in Pregnancy

2025

Khan, A., Khan, A., Malik, A., Satsangi, M., Khan, M. I., Jakkamsetti, P. S., Mehra, S., & Jahangiri, F. R. (2025). Motor Evoked Potential Monitoring in Pregnancy . J of Neurophysiological Monitoring, 3(2), 22–30. https://doi.org/10.5281/zenodo.15284110

Paper

Applications of Fiber Photometry in Social Behavior, Addiction, and Mood Affect Research: A Literature Review

2025

Nguyen, C., Salem, A., & Bird, A. (2025). Applications of Fiber Photometry in Social Behavior, Addiction, and Mood Affect Research: A Literature Review. J of Neurophysiological Monitoring, 3(2), 1–21. https://doi.org/10.5281/zenodo.15264490

Paper

Evaluating the Effectiveness of Intraoperative Neuromonitoring Modalities in Spinal Dysraphism Surgeries: A Systematic Review

2025

Anees, S., Nah, E., Chung, S., Ezhil, V., Khan, I., Mohiuddin, F., Tesy, S. U., & Jahangiri, F. R. (2025). Evaluating the Effectiveness of Intraoperative Neuromonitoring Modalities in Spinal Dysraphism Surgeries: A Systematic Review. J of Neurophysiological Monitoring, 3(1), 61–92. https://doi.org/10.5281/zenodo.14786910

Paper

Enhancing the Effectiveness of Monitoring the Robust Bulbocavernosus Reflex in Cauda Equina Surgeries: Harnessing Machine Learning to Decode the Complexity of Stimulation Parameters

2025

Jahangiri, F. R., Alzahrany, M., Aziz, H., Nguyen, L., Qayum, A., Mohamed, J., Gangardiwala, Z., & Ejaz, M. U. (2025). Enhancing the Effectiveness of Monitoring the Robust Bulbocavernosus Reflex in Cauda Equina Surgeries: Harnessing Machine Learning to Decode the Complexity of Stimulation Parameters . J of Neurophysiological Monitoring, 3(1), 36–60. https://doi.org/10.5281/zenodo.14516690

Case Report

IONM During Peripheral Nerve Hand Surgeries

2025

Jahangiri, F. R., Jahangiri, R. H., Khan, A., & Khan, M. I. (2025). Intraoperative Neurophysiological Monitoring (IONM) During Peripheral Nerve Hand Surgeries. J of Neurophysiological Monitoring, 3(1), 28–35. https://doi.org/10.5281/zenodo.14426668

Paper

Literature Review of Subcortical Mapping Techniques in Glioblastoma Surgeries

2025

Satsangi, M., Iduh, C., & Jahangiri, F. R. (2025). Literature Review of Subcortical Mapping Techniques in Glioblastoma Surgeries. J of Neurophysiological Monitoring, 3(1), 8–27. https://doi.org/10.5281/zenodo.14420746

Paper

Efficacy of Sugammadex as a Reversal with an Optimized Train of Four Stimulation Parameters

2025

Jahangiri, F. R., De Curtis, A., Workneh, E., Aziz, H., & Murimbechi, Z. (2024). Efficacy of Sugammadex as a Reversal with an Optimized Train of Four Stimulation Parameters. J of Neurophysiological Monitoring, 2(3), 45–62. https://doi.org/10.5281/zenodo.13945416

Paper

Multimodality IONM with Selective Dorsal Root Rhizotomy For patients with Cerebral Palsy

2025

Kamran, N., Khan, M. I., Hasnain, S., Jahangiri, R. H., Qayyum, A., Muhammad, A., & Jahangiri, F. R. (2024). Multimodality Intraoperative Neurophysiological Monitoring (IONM) with Selective Dorsal Root Rhizotomy For patients with Cerebral Palsy. J of Neurophysiological Monitoring, 2(3), 31–44. https://doi.org/10.5281/zenodo.13927264

Paper

Sensitivity and Specificity of IONM in Lumbar Spinal Surgery: A Meta-Analysis

2025

Dave, N., Jaimson, N. M., Siraj, R., Oladiji, J., & Jahangiri, F. R. (2024). Sensitivity and Specificity of Intraoperative Neurophysiological Monitoring in Lumbar Spinal Surgery: A Meta-Analysis . J of Neurophysiological Monitoring, 2(3), 21–30. https://doi.org/10.5281/zenodo.13917244

Paper

The Impact of Neurophysiological Monitoring on Patient Outcomes in Carotid Endarterectomy: A Meta-Analysis

2025

Jahangiri, F. R., Salazar, M., Arjarapu, R., & Gutierrez, E. (2024). The Impact of Neurophysiological Monitoring on Patient Outcomes in Carotid Endarterectomy: A Meta-Analysis. J of Neurophysiological Monitoring, 2(3), 1–11. https://doi.org/10.5281/zenodo.12588227

Paper

ASNM SEP Position Statement 2024

2024

Toleikis JR, Pace C, Jahangiri FR, Hemmer LB, Toleikis SC. Intraoperative somatosensory evoked potential (SEP) monitoring: an updated position statement by the American Society of Neurophysiological Monitoring. J Clin Monit Comput. 2024 Oct;38(5):1003-1042. doi: 10.1007/s10877-024-01201-x

Paper

The Advantages of Using IONM in Hip Surgeries: A Meta-Analysis

2024

Sam, A., Parapperi, R., Isa, U., Mumtaz, M., & Jahangiri, F. R. (2024). The Advantages of Using Intraoperative Neurophysiological Monitoring in Hip Surgeries: A Meta-Analysis. J of Neurophysiological Monitoring, 2(2), 46–59. https://doi.org/10.5281/zenodo.11152081

Paper

Exploring Meditation Techniques through EEG: A Systematic Review Contrasting Focused Attention and Open Monitoring Practices

2024

Garcia, C., Hosabettu, V., Vintila, T., & Jahangiri, F. R. (2023). Exploring Meditation Techniques through EEG: A Systematic Review Contrasting Focused Attention and Open Monitoring Practices. J of Neurophysiological Monitoring, 2(2), 31–45. Retrieved from https://jneurophysiologicalmonitoring.com/index.php/pub/article/view/54

Paper

Mapping of the Language Cortex

2023

Kabir SS, Jahangiri FR, Rinesmith C, Vilches CS, Chakarvarty S. Intraoperative Testing During the Mapping of the Language Cortex. Cureus. 2023 Mar 26;15(3):e36718. doi: 10.7759/cureus.36718. Erratum in: Cureus. 2025 Sep 16;17(9):c299. doi: 10.7759/cureus.c299.

Paper

Scoliosis Surgery With Continuous IONM

2022

Jahangiri FR, Jahangiri RH, Asad H, Farooq L, Khattak WH. Scoliosis Corrective Surgery With Continuous Intraoperative Neurophysiological Monitoring (IONM). Cureus. 2022 Oct 5;14(10):e29958. doi: 10.7759/cureus.29958.

Paper

Deep Brain Stimulation For Parkinson's Disease

2022

Fejeran J, Salazar F, Alvarez CM, Jahangiri FR. Deep Brain Stimulation and Microelectrode Recording for the Treatment of Parkinson's Disease. Cureus. 2022 Aug 11;14(8):e27887. doi: 10.7759/cureus.27887.

Paper

Carotid Endarterectomy Surgeries

2022

Jahangiri FR, Liang M, Huckabey M, Baloney N, Sharifi S. Carotid Endarterectomy Surgeries: A Multimodality Intraoperative Neurophysiological Monitoring Approach. Cureus. 2022 Jul 4;14(7):e26556. doi: 10.7759/cureus.26556.

Paper

Taniguchi Versus Penfield Method

2022

Jahangiri FR, Liang M, Kabir SS, Khowash O. Motor Mapping of the Brain: Taniguchi Versus Penfield Method. Cureus. 2022 May 11;14(5):e24901. doi: 10.7759/cureus.24901.

Paper

ASNM and ASN joint guidelines for TCD

2022

Razumovsky AY, Jahangiri FR, Balzer J, Alexandrov AV. ASNM and ASN joint guidelines for transcranial Doppler ultrasonic monitoring: An update. J Neuroimaging. 2022 Sep;32(5):781-797. doi: 10.1111/jon.13013.

Paper

Emerging Super-specialty of Neurology: IONM

2021

Ali L, Jahangiri FR, Ali A, Belkhair S, Elalamy O, Adeli G, Alghazow M, Krishnan R, Karim F, Iqrar A, Raza A. Emerging Super-specialty of Neurology: Intraoperative Neurophysiological Monitoring (IONM) and Experience in Various Neurosurgeries at a Tertiary Care Hospital in Doha, Qatar. Cureus. 2021 Dec 15;13(12):e20432. doi: 10.7759/cureus.20432.

Letter to Editor: SnSSEP

Response to a Letter to the Editor

2021

Jahangiri FR, Overzet K. Response to a Letter to the Editor. Neurodiagn J. 2021 Dec;61(4):239-240. doi: 10.1080/21646821.2021.2001629.

Paper

Mapping of the Language Cortex

2021

Jahangiri FR, Chima GS, Pearson M, Jackson J, Siddiqui AA. Mapping of the Language Cortex. Cureus. 2021 May 11;13(5):e14960. doi: 10.7759/cureus.14960.

Paper

Distal Stimulation Site for Saphenous Nerve SSEP

2021

Overzet K, Mora D, Faust E, Krisko L, Welch D, Jahangiri FR. Distal Stimulation Site at the Medial Tibia for Saphenous Nerve Somatosensory Evoked Potentials (DSn-SSEPs) in Lateral Lumbar Spine Procedures. Neurodiagn J. 2021 Jun;61(2):72-85. doi: 10.1080/21646821.2021.1903277.

Paper

Mapping of the Motor Cortex

2020

Jahangiri FR, Dobariya A, Kruse A, Kalyta O, Moorman JD. Mapping of the Motor Cortex. Cureus. 2020 Sep 25;12(9):e10645. doi: 10.7759/cureus.10645.

Paper

IONM During Trigeminal Schwannoma Surgery

2020

Jahangiri FR, Azam A, Asdi RA, Ahmad I, Basha SI. Intraoperative Neurophysiological Monitoring During Trigeminal Schwannoma Surgery. Cureus. 2020 Sep 3;12(9):e10218. doi: 10.7759/cureus.10218.

Paper

Mapping of the Somatosensory Cortex

2020

Jahangiri FR, Pautler K, Watters K, Anjum SS, Bennett GL. Mapping of the Somatosensory Cortex. Cureus. 2020 Mar 19;12(3):e7332. doi: 10.7759/cureus.7332.

Paper

IONM During Shoulder Surgeries

2020

Jahangiri FR, Blaylock J, Qadir N, Ramsey JA. Multimodality Intraoperative Neurophysiological Monitoring (IONM) During Shoulder Surgeries. Neurodiagn J. 2020 Jun;60(2):96-112. doi: 10.1080/21646821.2020.1743952.

Paper

Bulbocavernosus Reflex Monitoring During Intramedullary Conus Tumor Surgery

2020

Overzet K, Jahangiri FR, Funk R. Bulbocavernosus Reflex Monitoring During Intramedullary Conus Tumor Surgery. Cureus. 2020 Mar 10;12(3):e7233. doi: 10.7759/cureus.7233.

Paper

Radial Nerve SSEP (Rn-SSEP): Is It Reliable?

2019

Jahangiri FR, Qadir N, Blaylock J, Cronce-Solano L, Ramsey J. Waveform Window #46: Radial Nerve SSEP (Rn-SSEP): Is It Reliable? Neurodiagn J. 2019;59(4):232-235. doi: 10.1080/21646821.2019.1680085.

Letter to Editor

Response to a Letter to the Editor: IONM & ACDF

2019

Wilent WB, Ney JP, Balzer J, Donohue ML, Gertsch JH, Holdefer R, Jahangiri FR, Overzet K, Shils J, Vogel R. Letter to the Editor. Intraoperative neurophysiological monitoring and ACDF. J Neurosurg Spine. 2019 Oct 4;32(1):152-153. doi: 10.3171/2019.6.SPINE19641.

Paper

Intraoperative T-EMG from External Urethral Sphincter Muscles During Spine Surgeries

2019

Jahangiri FR, Asdi RA, Tarasiewicz I, Azzubi M. Intraoperative Triggered Electromyography Recordings from the External Urethral Sphincter Muscles During Spine Surgeries. Cureus. 2019 Jun 10;11(6):e4867. doi: 10.7759/cureus.4867.

Paper

Motor Evoked Potential Recordings from the Urethral Sphincter Muscles (USMEPs) during Spine Surgeries

2019

Jahangiri FR, Silverstein JW, Trausch C, Al Eissa S, George ZM, DeWal H, Tarasiewicz I. Motor Evoked Potential Recordings from the Urethral Sphincter Muscles (USMEPs) during Spine Surgeries. Neurodiagn J. 2019;59(1):34-44. doi: 10.1080/21646821.2019.1572375.

Letter to Editor

Response to: Is the new ASNM IONM supervision "guideline" a trustworthy guideline? A commentary

2019

Gertsch JH, Moreira JJ, Lee GR, Hastings JD, Ritzl E, Eccher MA, Shils JL, Balzer GK, Balzer JR, Boucharel W, Guo L, Hanson LL, Hemmer LB, Jahangiri FR, Mendez Vigil JA, Vogel RW, Wierzbowski LR, Wilent WB, Zuccaro JS, Yingling CD. Response to: Is the new ASNM intraoperative neuromonitoring supervision "guideline" a trustworthy guideline? A commentary. J Clin Monit Comput. 2019 Apr;33(2):193-194. doi: 10.1007/s10877-019-00288-x.

Paper

Multimodality IONM in Anterior Hip Arthroscopic Repair Surgeries

2019

Overzet K, Kazewych M, Jahangiri FR. Multimodality Intraoperative Neurophysiological Monitoring (IONM) in Anterior Hip Arthroscopic Repair Surgeries. Cureus. 2018 Sep 22;10(9):e3346. doi: 10.7759/cureus.3346.

Paper

ASNM Practice Guidelines for the Supervising Professional: IONM

2019

Gertsch JH, Moreira JJ, Lee GR, Hastings JD, Ritzl E, Eccher MA, Cohen BA, Shils JL, McCaffrey MT, Balzer GK, Balzer JR, Boucharel W, Guo L, Hanson LL, Hemmer LB, Jahangiri FR, Mendez Vigil JA, Vogel RW, Wierzbowski LR, Wilent WB, Zuccaro JS, Yingling CD; membership of the ASNM. Practice guidelines for the supervising professional: intraoperative neurophysiological monitoring. J Clin Monit Comput. 2019 Apr;33(2):175-183. doi: 10.1007/s10877-018-0201-9.

Case Report

Sudden Unexpected Change of Latency during Median Nerve Phase Reversal

2018

Jahangiri FR, Overzet K, Crosier T, Tarasiewicz I. Waveform Window #42: Sudden Unexpected Change of Latency during Median Nerve Phase Reversal. Neurodiagn J. 2018;58(3):182-188. doi: 10.1080/21646821.2018

Paper

Benefit of IONM in a Pediatric Patient with Spinal Dysmorphism, Split Cord Malformation, and Scoliosis

2017

Jahangiri FR, Sayegh SA, Azzubi M, Alrajhi AM, Annaim MM, Al Sharif SA, Aziz T, Al Eissa S. Benefit of Intraoperative Neurophysiological Monitoring in a Pediatric Patient with Spinal Dysmorphism, Split Cord Malformation, and Scoliosis. Neurodiagn J. 2017;57(4):295-307. doi: 10.1080/21646821.2017.1396780.

Case Report

Vertebral Column Resection for Kyphoscoliosis in a Patient with Ehlers-Danlos Syndrome: An IONM Alert

2016

Jahangiri FR, Al Eissa S, Sayegh S, Al Helal F, Al-Sharif SA, Annaim MM, Muhammad S, Aziz T. Vertebral Column Resection for Kyphoscoliosis in a Patient with Ehlers-Danlos Syndrome: An Intraoperative Neurophysiological Monitoring Alert. Cureus. 2016 Aug 31;8(8):e759. doi: 10.7759/cureus.759.

Case Report

Computer-Assisted Navigation During an Anterior-Posterior En Bloc Resection of a Sacral Tumor

2015

Al Eissa S, Al-Habib AF, Jahangiri FR. Computer-Assisted Navigation During an Anterior-Posterior En Bloc Resection of a Sacral Tumor. Cureus. 2015 Nov 4;7(11):e373. doi: 10.7759/cureus.373.

Case Report

IONM for Cordotomy Procedures

2015

Jahangiri FR. Intraoperative Neurophysiological Monitoring (IONM) for Cordotomy Procedures. Neurodiagn J. 2015 Sep;55(3):169-79. doi: 10.1080/21646821.2015.1071142.

Case Report

Early detection of pedicle screw-related spinal cord injury by continuous IONM

2014

Jahangiri FR, Sheryar M, Al Behairy Y. Early detection of pedicle screw-related spinal cord injury by continuous intraoperative neurophysiological monitoring (IONM). Neurodiagn J. 2014 Dec;54(4):323-37. doi: 10.1080/21646821.2014.11106817.

Case Report

Neurophysiological monitoring of the spinal sensory and motor pathways during embolization of spinal arteriovenous malformations - Propofol: A safe alternative

2014

Jahangiri FR, Sheryar M, Al Okaili R. Neurophysiological monitoring of the spinal sensory and motor pathways during embolization of spinal arteriovenous malformations--propofol: a safe alternative. Neurodiagn J. 2014 Jun;54(2):125-37.

Case Report

IONM during Sacrectomy Procedures

2013

Jahangiri FR, Al Eissa S, Jahangiri AF, Al-Habib A. Intraoperative neurophysiological monitoring during sacrectomy procedures. Neurodiagn J. 2013 Dec;53(4):312-22.

Paper

Multimodality IONM during Tibial/Fibular Osteotomies for preventing peripheral nerve injuries

2013

Jahangiri FR. Multimodality neurophysiological monitoring during tibial/fibular osteotomies for preventing peripheral nerve injuries. Neurodiagn J. 2013 Jun;53(2):153-68.

Paper

Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing IONM

2012

Jahangiri FR, Minhas M, Jane J Jr. Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing intraoperative neurophysiological monitoring. Neurodiagn J. 2012 Dec;52(4):320-32.

Paper

Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing IONM

2012

Jahangiri FR, Minhas M, Jane J Jr. Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing intraoperative neurophysiological monitoring. Neurodiagn J. 2012 Dec;52(4):320-32.

Paper

Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing IONM

2012

Jahangiri FR, Minhas M, Jane J Jr. Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing intraoperative neurophysiological monitoring. Neurodiagn J. 2012 Dec;52(4):320-32.

Paper

IONM: Lessons learned from 32 Case Events in 2069 Spine Cases

2012

Eager M, Shimer A, Jahangiri FR, Shen F, Arlet V. Intraoperative neurophysiological monitoring (IONM): lessons learned from 32 case events in 2069 spine cases. Am J Electroneurodiagnostic Technol. 2011 Dec;51(4):247-63.

Paper

Preventing Position-Related Brachial Plexus injury with intraoperative SSEP and TCeMEP during Anterior Cervical Spine Surgery

2011

Jahangiri FR, Holmberg A, Vega-Bermudez F, Arlet V. Preventing position-related brachial plexus injury with intraoperative somatosensory evoked potentials and transcranial electrical motor evoked potentials during anterior cervical spine surgery. Am J Electroneurodiagnostic Technol. 2011 Sep;51(3):198-205.

Paper

Limiting the current density during localization of the primary motor cortex by using a tangential-radial cortical somatosensory evoked potentials model, direct electrical cortical stimulation, and electrocorticography

2011

Jahangiri FR, Sherman JH, Sheehan J, Shaffrey M, Dumont AS, Vengrow M, Vega-Bermudez F. Limiting the current density during localization of the primary motor cortex by using a tangential-radial cortical somatosensory evoked potentials model, direct electrical cortical stimulation, and electrocorticography. Neurosurgery. 2011 Oct;69(4):893-8. doi: 10.1227/NEU.0b013e3182230ac3.

Paper

Protecting the Genitofemoral Nerve during Direct/Extreme Lateral Interbody Fusion (DLIF/XLIF) Procedures

2011

Jahangiri FR, Sherman JH, Holmberg A, Louis R, Elias J, Vega-Bermudez F. Protecting the genitofemoral nerve during direct/extreme lateral interbody fusion (DLIF/XLIF) procedures. Am J Electroneurodiagnostic Technol. 2010 Dec;50(4):321-35.

Paper

IONM: Lessons Learned from 32 Case Events in 2095 Spine Cases

2011

Eager M, Jahangiri F, Shimer A, Shen F, Arlet V. Intraoperative neuromonitoring: lessons learned from 32 case events in 2095 spine cases. Evid Based Spine Care J. 2010 Aug;1(2):58-61. doi: 10.1055/s-0028-1100917.

Umair M, Asghar R M, Jahangiri F R. The Incidence Rate of Motor Evoked Potential Alerts in 1159 Lumbar Spinal Surgeries. J Neurol Neurophysiol. 2022, 13(10), 001-003.

The Incidence Rate of Motor Evoked Potential Alerts in 1,159 Lumbar Spinal Surgeries

 Spinal surgery is associated with a high rate of neurological sequelae due to damage to the spinal nerve roots. This study aims to determine the most common alert type during lumbar spinal surgeries, including either anesthetic/physiological, positioning, or surgical. 

We retrospectively reviewed 1,159 extradural spinal surgeries with Intraoperative Neurophysiological Monitoring (IONM) from January 2019 to March 2021 to evaluate the incidence of events. We analyzed the Motor Evoked Potentials (MEP) alerts and changes in the neurophysiological signals. Cases were categorized by procedure type, muscles, and then by the level (upper; or lower) that the MEP alert occurred.

Jahangiri F R, Liang M, Huckabey M, et al. (July 04, 2022) Carotid Endarterectomy Surgeries: A Multimodality Intraoperative Neurophysiological Monitoring Approach. Cureus 14(7): e26556. doi:10.7759/cureus.26556

Carotid Endarterectomy and How Neuromonitoring Can Help

The World Health Organization lists cardiovascular disease as a leading cause of mortality worldwide, and in America alone, stroke was the fifth leading cause of all deaths in 2019. Plaque build-up in the carotid arteries restricts normal blood flow, often resulting in transient ischemic attacks (TIA). This condition, called carotid artery stenosis, can be diagnosed through multiple TIAs in symptomatic cases or through tests such as ultrasound, computed tomography angiography (CTA), cerebral angiography, and magnetic resonance angiography in asymptomatic patients. 
 
Carotid endarterectomy (CEA) is a procedure that focuses on removing plaque blockage in the carotid arteries. Generally, this surgery is recommended only for moderate to severe carotid stenosis in symptomatic patients and severe carotid stenosis in asymptomatic patients. CEA involves placing a cross-clamp on all three carotid artery branches (external, common, internal) before removing the plaque build-up in the opened artery. 
 
Most of the risk associated with CEA comes from ischemic risk during the procedure. 
Cross-clamp placement restricts blood flow through the carotid arteries to the brain on the ipsilateral side of the procedure. Typically, patients with good collateral circulation in the circle of Willis can maintain an adequate level of perfusion through the contralateral carotid arteries. However, 20 to 50% of patients have poor collateral circulation, and there is a risk of cerebral ischemia potentially causing an intraoperative stroke. 
 
Intraoperative neurophysiological monitoring (IONM) can minimize these risks by continuously providing valuable information about the cerebral perfusion level. IONM modalities, somatosensory evoked potentials (SSEPs), and electroencephalography (EEG) can indirectly measure cerebral perfusion. Any changes in these real-time recordings, often in the form of decreased waveform complexity or complete signal loss, reflect critical decreases in perfusion. This allows the surgeon to determine which surgical manipulation may place stress on neural structures and the appropriate intervention to minimize any irreversible damage resulting in a postoperative deficit.
 
Often, the intervention for cross-clamp-induced changes is the placement of an intraluminal shunt within the dissected carotid artery to reroute blood flow around the surgical site. However, shunt placement in all patient cases, routine shunting, is highly discouraged as it can increase the risk of dislodging microemboli, causing a postoperative stroke. Therefore, shunt placement is recommended only when necessary, with selective shunt placement determined by criteria of SSEP and EEG changes after preliminary cross-clamping tests to assess the patient’s degree of collateral circulation, making IONM an essential part of CEA. 
 
Outside of selective shunt placement, SSEP and EEG should also be run continuously throughout the surgery to detect ischemic changes caused by other surgical maneuvers. Microemboli can also be dislodged during the reperfusion of the carotid arteries after the clamp is removed, causing an intraoperative or postoperative stroke. Other neuromonitoring modalities such as transcranial Doppler (TCD) can also be added for better visualization and quantification of emboli in the arteries. 
 
Multiple scientific studies and reviews have also found that multimodality IONM using both SSEP and EEG has yielded the highest specificity and sensitivity in predicting postoperative deficits, supporting those changes in these recordings reflect stress on neural structures. IONM’s utility in monitoring cerebral perfusion levels, a critical aspect of the procedure, is why IONM is considered the standard of care for CEA.

Mar 1, 2022

Chapter: Quantitative EEG - An Introduction

Muhammad Umair MD, Muhammad Roshan Asghar MD, Faisal R. Jahangiri MD, CNIM, D.ABNM, FASNM, FASET, Junaid Kalia MD

An introduction to Quantitative EEG in essential neurology. A chapter for readers in open access pocketbook of neurology by AINeurCare Academy.

Multimodality Neurophysiological Monitoring During Tibial/Fibular Osteotomies for Preventing Peripheral Nerve Injuries

Intraoperative Neurophysiological Monitoring (IONM) is not used routinely during tibial and fibular osteotomy procedures. Pediatric patients who present with Tibia Vara (Blount's disease), juvenile osteochondrosis, Genu Valgum (Knock-Knees), etc. are surgically treated with tibial and fibular osteotomy. These patients have a high risk of postoperative weakness or foot drop with or without sensory deficits. The incidence of postoperative neurological deficits ranges from 2% to 20%. The postoperative neurological complications can be minimized by utilizing IONM

Tibia Vara (Blount's Disease)
It is a growth disorder of the Tibia (shin bone) that causes the lower leg to angle inward, resembling a bowleg.
Juvenile Osteochondrosis
Occur in children characterized by interruption of the blood supply of a bone, in particular to the epiphysis, followed by localized bony necrosis and later, re-growth of the bone.
Genu Valgum:
Commonly called "knock-knees" is a condition where the knees angle in and touch one another when the legs are straightened.

Concerns during Tibial and Fibular osteotomies include ipsilateral lower limb motor and sensory function, due to peroneal nerve injuries by osteotomy at the fibular neck. Total Intravenous Anesthesia (TIVA) without any muscle relaxant, inhalational agent, or dexmedetomidine is reccommended.

Jan 17, 2022

Chapter: Basics of EEG

Shehzeen Fatima Memon, Faisal Jahangiri

A quick reference guide to basics of EEG in essential neurology. A chapter for readers in open access pocketbook of neurology by AINeurCare Academy.

Train of Four (TOF) Monitoring: Are We Doing It The Right Way?

In 1970, Ali et al. developed and published the technique of Train of Four (TOF) monitoring (Ali HH, 1970). TOF pattern was developed for assessing neuromuscular block in the anesthetized patient. TOF was developed as a stimulation pattern that did not require a comparison to a control response before administration of a neuromuscular blocking agent. It was done by stimulating the ulnar nerve with a TOF supra-maximal twitch stimuli.

Use of IONM during Selective Dorsal Root Rhizotomy (SDR) Procedures for the Treatment of Spasticity in Patients with Cerebral Palsy

Selective dorsal root rhizotomy (SDR): SDR has been used effectively in the treatment of spasticity in some children with cerebral palsy. SDR is a neurosurgical procedure that involves selectively sectioning (cutting) of some of the sensory (dorsal) nerve fibers with abnormal responses that enter the spinal cord and synapse with lower motor neurons. The SDR technique can be used under electrophysiological guidance in a patient with cerebral palsy for the successful treatment of spasticity.

A multimodality Intraoperative Neurophysiological Monitoring (IONM) approach with Somatosensory Evoked Potentials (SSEP), Transcranial electrical Motor Evoked Potentials (TCeMEP), and Electromyography (EMG) is recommended during SDR procedures. Baselines responses are recorded after intubation and before incision under general anesthesia. The spontaneous (s-EMG) and triggered EMG (t-EMG) can be effectively used intraoperatively for the selection of dorsal rootlets. Rootlets with abnormal EMG firing patterns are cut in patients diagnosed with cerebral palsy for the reduction of muscle spasticity.

Utilizing Longer Intramuscular Needle Pair Electrodes: What are we Missing in Our Intraoperative Muscle Recordings?

(Paper was presented by Dr. Faisal Jahangiri at the 2015 annual meeting of the American Society of Neurophysiological Monitoring (ASNM) in Chicago, Illinois. It received a Lead Author-Scientific Achievement Award from the ASNM research committee). Dr. Jahangiri also presented this paper at the 2015 annual meeting of the American Neurodiagnostic Society (ASET) in Weston, Florida.

Objective: This study illustrates the benefit of utilizing longer 37mm and 50mm intramuscular needle pair electrodes for recording Transcranial electrical Motor Evoked Potentials (TCeMEP) in Rectus Femoris (RF) muscle during various surgeries in obese patients, as opposed to the regularly used sub-dermal 13 mm needle electrodes, which can miss muscle activity (EMG) due to presence of adipose tissue.  The 37 mm and 50mm intramuscular needle pair electrodes increased accuracy and reliability of TCeMEP recording at lower stimulation thresholds.

Multimodality Intraoperative Neurophysiological Monitoring (IONM) for Preventing Cranial Nerve Injuries during High Risk Brain Surgeries

There are 12 pairs of cranial nerves (CN). All of them can be monitored except CN I (Olfactory). Various monitoring techniques (also known as Modalities) that can be utilized intraoperatively include spontaneous Electromyography (s-EMG), triggered Electromyography (t-EMG), Cranial Nerves Motor Evoked Potentials (CN-MEP), Nerve Action Potentials (NAP), Visual Evoked Potentials (VEP), Somatosensory Evoked Potentials (SSEP) (CN V and CN VII) and Brainstem Auditory Evoked Potentials (ECoch, AN-CAP, BAEP). CN II (Optic) is a sensory nerve that can be monitored intraoperatively by visual stimulation by flash goggles and recording from the retina (ERG) and visual cortex (VEP). CN V (Trigeminal) has a sensory division which is monitored for Trigeminal SEP (TSEP). CN VIII (VestibuloCochlear) is also a sensory nerve that can be monitored by auditory stimulation. Factors affecting BAER response may include N2O, hypothermia, and inhalational agents. Multilevel auditory responses are recorded from the tympanic membrane/cochlea (Electrocochleography: ECoch), directly from the auditory nerve (Auditory Nerve Compound Action Potentials: AN-CAP) and the brainstem (BAEP) when preservation of hearing is a high priority.

Protecting the Visual Pathways During Optic Nerve Surgery Using Intraoperative Visual Evoked Potentials (VEP)

 This case report illustrates the benefit of utilizing Intraoperative Neurophysiological Monitoring (IONM) during the resection of an optic nerve lesion. A multimodality IONM utilized Electroretinogram (ERG), Visual Evoked Potentials (VEP), and Electroencephalography (EEG). A 47-year-old female presented with left intracranial meningioma and decreased vision in the right eye. An MRI showed a tumor attached to the left optic nerve and posteriorly displacing optic nerve and chiasm to the right. After induction and patient positioning, LED goggles were placed and secured on both eyes for performing VEP. The VEP responses were absent at baseline due to the inhalational agent. After switching to Total Intravenous Anesthesia (TIVA), ERG responses were recorded bilaterally. Baseline VEP and EEG recordings were obtained with good left VEP and absent right VEP responses. During tumor resection, there was a sudden decrease in left VEP responses. Retractors were removed immediately and the responses came back to baseline within a few minutes. The tumor was resected without any loss of vision intraoperatively. The patient noticed an improvement in her right eye four days post-operatively. One month post-operatively she continued to feel improvement. In this patient, the VEP was used effectively for the prevention of any loss of vision intra-operatively. The neurophysiological monitoring utilizing ERG and VEP helped prevent any further loss of vision and directing the surgeon intra-operatively 

Multimodality IONM in Anterior Hip Arthroscopic Repair Surgeries

Arthroscopic hip surgery is performed routinely for the treatment of various hip disorders. Leg traction during labral tear repair, femoroplasty, and acetabuloplasty for hip stabilization can stretch the peripheral nerves. This may cause temporary or permanent nerve injury. This study illustrates the benefit of utilizing multimodality Intraoperative Neurophysiological Monitoring (IONM) during hip surgical procedures.

We performed a retrospective review of 10 arthroscopic hip surgeries with neurophysiological monitoring at one medical center. The patients consisted of six females and four males (mean age: 48.9 years). The procedures were equally divided into left and right-sided procedures. IONM setup included posterior tibial, peroneal, and femoral or saphenous nerve somatosensory evoked potentials (SSEPs), transcranial electrical motor evoked potentials (TCeMEP), train of four (TOF), and electromyography (EMG) from the lower extremities.

All patients exhibited changes in IONM data during the surgical procedure. Changes in the latency and amplitude or loss of the lower SSEPs on the surgical side occurred in 36% of the monitorable SSEPs. The surgeon instructed the team to reduce the leg lengthening by removing traction when changes were observed. The SSEPs exhibited a full recovery in 75% of the affected lower extremity SSEPs. In the two instances of nonrecovery, the SSEP responses remained increased in latency or decreased in amplitude at closing, but the waveform was intact. There were five instances of complete loss of the waveform (four in the ipsilateral leg, and one in the contralateral leg) with recovery after traction was reduced. TCeMEP changes occurred in 53% of the ipsilateral lower muscles monitored. Many of the TCeMEP changes were attributed to ischemia of the feet and could not be resolved intraoperatively.

Multimodality IONM can be a beneficial and protective tool during surgical procedures involving hip and acetabular areas. Early identification of changes in evoked potentials during hip arthroscopy surgeries can minimize post-operative neurological deficits due to peripheral nerve injury and leg ischemia.

Vertebral Column Resection for Kyphoscoliosis in a Patient with Ehlers-Danlos Syndrome: An Intraoperative Neurophysiological Monitoring Alert

A 16-year-old male patient with Ehler-Danlos syndrome (EDS) and a back deformity since birth presented with severe kyphoscoliosis. The patient was neurologically intact but had respiratory and cardiac insufficiencies. A two-stage vertebral column resection (VCR) at T9-T10 with multiple level fusion with multimodality intraoperative neurophysiological monitoring (IONM) was planned. 

During the first stage, pedicle screws were placed at multiple spinal levels above and below the VCR level. Upper and lower somatosensory evoked potentials (SSEP), transcranial electrical motor evoked potentials (TCeMEP), and electromyography were monitored continuously and showed no significant changes. The second stage was performed one week later. Baseline SSEP and TCeMEP responses were present in all extremities. The surgeon was informed of a sudden 70% amplitude drop in TCeMEP in the lower limbs with stable SSEP after ligating one of the left nerves/vessels fully stretching the spinal cord. The surgeon removed the ligation, and an improvement in motor responses followed. Surgery proceeded with the highest levels of caution. Later, there was a sudden loss of TCeMEP and SSEP in the lower limbs bilaterally. The correction was released, mean arterial pressure was increased, and intravenous dexamethasone was administered. The surgical correction was aborted, and the decision was made to close the site. Lower SSEP and TCeMEP responses remained absent until closing, while upper SSEP and TCeMEP responses remained stable.

A wake-up test was done after closing. The patient moved his upper limbs but was unable to move his lower limbs bilaterally. The patient was sent for a magnetic resonance imaging scan while intubated and then sent to the intensive care unit. At 24 hours and 36 hours post-operation, the patient had no sensory and motor function below the T8 level. Forty-eight hours post-operation, the patient started to feel sensory stimuli at the T10 level. At one week post-operation, the patient regained sphincter functions, and at four weeks postoperatively, the patient’s hip flexors started to recover.

VCR in patients with EDS has a very high risk of damaging the spinal cord due to the fragile vasculature of the spinal cord. Real-time IONM is useful in the early identification of spinal cord injury in cases of this nature. 

Computer-Assisted Navigation During an Anterior-Posterior En Bloc Resection of a Sacral Tumor

Previously, a computer-based navigation system has not been used routinely for en-bloc resection of sacral tumors. In order to improve the accuracy of tumor resection, O-arm navigation was used to join anterior and posterior osteotomies during an en-bloc resection of a sacral Ewing’s sarcoma.

This case study describes the technique for en-bloc resection of a sacral Ewing’s sarcoma guided by O-arm computer navigation and intraoperative neurophysiological monitoring (IONM).

An 18-year-old male presented with weakness in his left lower extremity. MRI of the patient's spine showed a sacral mass causing compression of left S1 and S2 roots. A surgical resection was planned with anterior and posterior approaches. An O-arm computer navigation system was used to assist in meeting anterior osteotomy cuts with the posterior cuts to ensure complete resection of the sacral tumor with a safe margin.

Computer-assisted navigation was used along with IONM during this procedure to help guide the surgical team in an adequate tumor resection. There were no complications related to the use of the O-arm or the navigation system.

Computer navigation guidance is both useful and safe in sacral tumor resections. It enhanced the accuracy of the en-bloc removal of a sacral tumor with safe margins while protecting neural function and minimizing recurrence.