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Donald J Crammond - One of the best experts on this subject based on the ideXlab platform.
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diagnostic accuracy of Somatosensory Evoked Potential monitoring in evaluating neurological complications during endovascular aneurysm treatment
Operative Neurosurgery, 2018Co-Authors: William J Ares, Donald J Crammond, Parthasarathy D Thirumala, Miguel Habeych, Ramesh Grandhi, David M Panczykowski, Gregory M Weiner, Michael B Horowitz, Brian T Jankowitz, Ashutosh P JadhavAbstract:Background Somatosensory Evoked Potential (SSEP) monitoring is used extensively for early detection and prevention of neurological complications in patients undergoing many different neurosurgical procedures. However, the predictive ability of SSEP monitoring during endovascular treatment of cerebral aneurysms is not well detailed. Objective To evaluate the performance of intraoperative SSEP in the prediction postprocedural neurological deficits (PPNDs) after coil embolization of intracranial aneurysms. Methods This population-based cohort study included patients ≥18 years of age undergoing intracranial aneurysm embolization with concurrent SSEP monitoring between January 2006 and August 2012. The ability of SSEP to predict PPNDs was analyzed by multiple regression analyses and assessed by the area under the receiver operating characteristic curve. Results In a population of 888 patients, SSEP changes occurred in 8.6% (n = 77). Twenty-eight patients (3.1%) suffered PPNDs. A 50% to 99% loss in SSEP waveform was associated with a 20-fold increase in risk of PPND; a total loss of SSEP waveform, regardless of permanence, was associated with a greater than 200-fold risk of PPND. SSEPs displayed very good predictive ability for PPND, with an area under the receiver operating characteristic curve of 0.84 (95% CI 0.76-0.92). Conclusion This study supports the predictive ability of SSEPs for the detection of PPNDs. The magnitude and persistence of SSEP changes is clearly associated with the development of PPNDs. The utility of SSEP monitoring in detecting ischemia may provide an opportunity for neurointerventionalists to respond to changes intraoperatively to mitigate the Potential for PPNDs.
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abstract tp80 improving perioperative stroke detection during intracranial aneurysm surgery using Somatosensory Evoked Potential waveform analysis
Stroke, 2018Co-Authors: Eyad E Saca, Ahmed Kashkoush, Donald J Crammond, Jeffrey Balzer, Parthasarathy D ThirumalaAbstract:Background: Current alarm criteria for evaluating impending perioperative stroke using Somatosensory Evoked Potential (SSEP) intraoperative monitoring is a 50% reduction in amplitude or a 10% incre...
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diagnostic accuracy of combined multimodality Somatosensory Evoked Potential and transcranial motor Evoked Potential intraoperative monitoring in patients with idiopathic scoliosis
Spine, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Karthy Thiagarajan, Jessie Huang, Hannah Cheng, Donald J CrammondAbstract:STUDY DESIGN: Systematic review. OBJECTIVE: The aim of the study was to determine the predictive value of combined multimodality Somatosensory Evoked Potential (SSEP) and transcranial motor Evoked Potential (TcMEP) monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: The diagnostic of motor Evoked Potential monitoring and SSEP monitoring have been established. However, the predictive value of combined multimodality SSEP and TcMEP monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis has not been evaluated. METHODS: A systematic literature search was performed using PubMed/MEDLINE, Web of Science, and EMBASE from 1974 to January 2015. All titles and abstracts were independently reviewed by the authors. We included all studies that were (1) randomized controlled trials, prospective or retrospective cohort studies; (2) included patients with idiopathic scoliosis undergoing scoliosis correction surgery; (3) included multimodality SSEP and TcMEP monitoring during spinal surgery; (4) included immediate postoperative neurological assessment; (5) idiopathic scoliosis patient population n ≥25; and (6) published in English. RESULTS: Seven studies comprising a total of 2052 patients with idiopathic scoliosis were included in our meta-analysis. The incidence of neurological deficit in this cohort was 0.93%. The pooled sensitivity, specificity, and Diagnostic Odds Ratio were 82.6% (95% CI 56.7%-94.5%), 94.4% (95% CI 85.1%-98.0%), and 106.16 (95% CI 24.952-451.667), respectively. The area under the curve was 0.928, indicating excellent discriminatory ability. CONCLUSION: Idiopathic scoliosis corrective surgery patients who experience a new neurological deficit are 106.16 times more likely to have had an SSEP and/or TcMEP change during corrective procedures. The results of this meta-analysis demonstrate that combined multimodality SSEP and TcMEP monitoring possess some advantage over use of each alone, and that intraoperative neurophysiological monitoring may provide a valuable biomarker in detection of impending neurological injury. LEVEL OF EVIDENCE: 2.
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diagnostic accuracy of Somatosensory Evoked Potential monitoring during scoliosis fusion
Journal of Clinical Neuroscience, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Hannah L Cheng, Yoon K Loke, Kojo D Hamilton, Donald J CrammondAbstract:The goal of this review was to ascertain the diagnostic accuracy of intraoperative Somatosensory Evoked Potential (SSEP) changes to predict perioperative neurological outcome in patients undergoing spinal deformity surgery to correct adolescent idiopathic scoliosis (AIS). The authors searched PubMed/MEDLINE and World Science databases to retrieve reports and/or experiments from January 1950 through January 2014 for studies on SSEP use during AIS surgery. All motor and sensory deficits were noted in the neurological examination administered after the procedure which was used to determine the effectiveness of SSEP as an intraoperative monitoring technique. Fifteen studies identified a total of 4763 procedures on idiopathic patients. The observed incidence of neurological deficits was 1.11% (53/4763) of the sample population. Of the patients with new postoperative neurological deficits 75.5% (40/53) showed significant SSEP changes, and 24.5% (13/53) did not show significant change. Pooled analysis using the bivariate model showed SSEP change with pooled sensitivity (average 84%, 95% confidence interval 59-95%) and specificity (average 98%, 95% confidence interval 97-99%). The diagnostic odds ratio of a patient who had a new neurological deficit with SSEP changes was a diagnostic odds ratio of 340 (95% confidence interval 125-926). Overall, detection of SSEP changes had excellent discriminant ability with an area under the curve of 0.99. Our meta-analysis covering 4763 operations on idiopathic patients showed that it is a highly sensitive and specific test and that iatrogenic spinal cord injury resulting in new neurological deficits was 340 times more likely to have changes in SSEP compared to those without any new deficits.
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diagnostic value of Somatosensory Evoked Potential monitoring during cerebral aneurysm clipping a systematic review
World Neurosurgery, 2016Co-Authors: Parthasarathy D Thirumala, Donald J Crammond, Reshmi Udesh, Aditya Muralidharan, Karthy Thiagarajan, Yuefang Chang, Jeffrey BalzerAbstract:Background Perioperative stroke is a known complication in patients undergoing surgical clipping of cerebral aneurysms. Objective To evaluate whether intraoperative changes in Somatosensory-Evoked Potential (SSEP) monitoring during cerebral aneurysm clipping is diagnostic of perioperative stroke. Methods An electronic search of PubMed, Embase, and Web of Science databases was done for studies published through May 2015 on SSEP monitoring in cerebral aneurysm clipping for predicting postoperative outcomes. All titles and abstracts were screened independently on the basis of predetermined criteria. Inclusion criteria included randomized clinical trials and prospective or retrospective cohort reviews; patients with intracranial aneurysms who underwent surgical clipping with intra-operative SSEP monitoring and postoperative neurologic assessment; studies published in English on adult humans ≥18 years with sample size of ≥50; and studies inclusive of an abstract with adequate details on outcomes. Results A total of 14 articles with a sample population of 2015 patients were analyzed. SSEP monitoring demonstrated a strong mean specificity of 84.5% (95% confidence interval [95% CI] −76.3 to 90.3) but weaker sensitivity of 56.8% (95% CI 44.1−68.6) for predicting stroke. A diagnostic odds ratio of 7.772 (95% CI 5.133−11.767) suggested that the odds of observing an SSEP change among those with a postoperative neurologic deficit were 7 times greater than those without a neurologic deficit. Conclusion Intraoperative SSEP monitoring is highly specific for predicting neurologic outcome after cerebral aneurysm clipping. Patients with postoperative neurologic deficits are 7 times more likely to have had intraoperative SSEP changes. SSEP monitoring may help design prevention strategies to reduce stroke rates after cerebral aneurysm clipping.
Parthasarathy D Thirumala - One of the best experts on this subject based on the ideXlab platform.
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diagnostic accuracy of Somatosensory Evoked Potential monitoring in evaluating neurological complications during endovascular aneurysm treatment
Operative Neurosurgery, 2018Co-Authors: William J Ares, Donald J Crammond, Parthasarathy D Thirumala, Miguel Habeych, Ramesh Grandhi, David M Panczykowski, Gregory M Weiner, Michael B Horowitz, Brian T Jankowitz, Ashutosh P JadhavAbstract:Background Somatosensory Evoked Potential (SSEP) monitoring is used extensively for early detection and prevention of neurological complications in patients undergoing many different neurosurgical procedures. However, the predictive ability of SSEP monitoring during endovascular treatment of cerebral aneurysms is not well detailed. Objective To evaluate the performance of intraoperative SSEP in the prediction postprocedural neurological deficits (PPNDs) after coil embolization of intracranial aneurysms. Methods This population-based cohort study included patients ≥18 years of age undergoing intracranial aneurysm embolization with concurrent SSEP monitoring between January 2006 and August 2012. The ability of SSEP to predict PPNDs was analyzed by multiple regression analyses and assessed by the area under the receiver operating characteristic curve. Results In a population of 888 patients, SSEP changes occurred in 8.6% (n = 77). Twenty-eight patients (3.1%) suffered PPNDs. A 50% to 99% loss in SSEP waveform was associated with a 20-fold increase in risk of PPND; a total loss of SSEP waveform, regardless of permanence, was associated with a greater than 200-fold risk of PPND. SSEPs displayed very good predictive ability for PPND, with an area under the receiver operating characteristic curve of 0.84 (95% CI 0.76-0.92). Conclusion This study supports the predictive ability of SSEPs for the detection of PPNDs. The magnitude and persistence of SSEP changes is clearly associated with the development of PPNDs. The utility of SSEP monitoring in detecting ischemia may provide an opportunity for neurointerventionalists to respond to changes intraoperatively to mitigate the Potential for PPNDs.
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abstract tp80 improving perioperative stroke detection during intracranial aneurysm surgery using Somatosensory Evoked Potential waveform analysis
Stroke, 2018Co-Authors: Eyad E Saca, Ahmed Kashkoush, Donald J Crammond, Jeffrey Balzer, Parthasarathy D ThirumalaAbstract:Background: Current alarm criteria for evaluating impending perioperative stroke using Somatosensory Evoked Potential (SSEP) intraoperative monitoring is a 50% reduction in amplitude or a 10% incre...
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diagnostic accuracy of combined multimodality Somatosensory Evoked Potential and transcranial motor Evoked Potential intraoperative monitoring in patients with idiopathic scoliosis
Spine, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Karthy Thiagarajan, Jessie Huang, Hannah Cheng, Donald J CrammondAbstract:STUDY DESIGN: Systematic review. OBJECTIVE: The aim of the study was to determine the predictive value of combined multimodality Somatosensory Evoked Potential (SSEP) and transcranial motor Evoked Potential (TcMEP) monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: The diagnostic of motor Evoked Potential monitoring and SSEP monitoring have been established. However, the predictive value of combined multimodality SSEP and TcMEP monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis has not been evaluated. METHODS: A systematic literature search was performed using PubMed/MEDLINE, Web of Science, and EMBASE from 1974 to January 2015. All titles and abstracts were independently reviewed by the authors. We included all studies that were (1) randomized controlled trials, prospective or retrospective cohort studies; (2) included patients with idiopathic scoliosis undergoing scoliosis correction surgery; (3) included multimodality SSEP and TcMEP monitoring during spinal surgery; (4) included immediate postoperative neurological assessment; (5) idiopathic scoliosis patient population n ≥25; and (6) published in English. RESULTS: Seven studies comprising a total of 2052 patients with idiopathic scoliosis were included in our meta-analysis. The incidence of neurological deficit in this cohort was 0.93%. The pooled sensitivity, specificity, and Diagnostic Odds Ratio were 82.6% (95% CI 56.7%-94.5%), 94.4% (95% CI 85.1%-98.0%), and 106.16 (95% CI 24.952-451.667), respectively. The area under the curve was 0.928, indicating excellent discriminatory ability. CONCLUSION: Idiopathic scoliosis corrective surgery patients who experience a new neurological deficit are 106.16 times more likely to have had an SSEP and/or TcMEP change during corrective procedures. The results of this meta-analysis demonstrate that combined multimodality SSEP and TcMEP monitoring possess some advantage over use of each alone, and that intraoperative neurophysiological monitoring may provide a valuable biomarker in detection of impending neurological injury. LEVEL OF EVIDENCE: 2.
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diagnostic accuracy of Somatosensory Evoked Potential monitoring during scoliosis fusion
Journal of Clinical Neuroscience, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Hannah L Cheng, Yoon K Loke, Kojo D Hamilton, Donald J CrammondAbstract:The goal of this review was to ascertain the diagnostic accuracy of intraoperative Somatosensory Evoked Potential (SSEP) changes to predict perioperative neurological outcome in patients undergoing spinal deformity surgery to correct adolescent idiopathic scoliosis (AIS). The authors searched PubMed/MEDLINE and World Science databases to retrieve reports and/or experiments from January 1950 through January 2014 for studies on SSEP use during AIS surgery. All motor and sensory deficits were noted in the neurological examination administered after the procedure which was used to determine the effectiveness of SSEP as an intraoperative monitoring technique. Fifteen studies identified a total of 4763 procedures on idiopathic patients. The observed incidence of neurological deficits was 1.11% (53/4763) of the sample population. Of the patients with new postoperative neurological deficits 75.5% (40/53) showed significant SSEP changes, and 24.5% (13/53) did not show significant change. Pooled analysis using the bivariate model showed SSEP change with pooled sensitivity (average 84%, 95% confidence interval 59-95%) and specificity (average 98%, 95% confidence interval 97-99%). The diagnostic odds ratio of a patient who had a new neurological deficit with SSEP changes was a diagnostic odds ratio of 340 (95% confidence interval 125-926). Overall, detection of SSEP changes had excellent discriminant ability with an area under the curve of 0.99. Our meta-analysis covering 4763 operations on idiopathic patients showed that it is a highly sensitive and specific test and that iatrogenic spinal cord injury resulting in new neurological deficits was 340 times more likely to have changes in SSEP compared to those without any new deficits.
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diagnostic value of Somatosensory Evoked Potential monitoring during cerebral aneurysm clipping a systematic review
World Neurosurgery, 2016Co-Authors: Parthasarathy D Thirumala, Donald J Crammond, Reshmi Udesh, Aditya Muralidharan, Karthy Thiagarajan, Yuefang Chang, Jeffrey BalzerAbstract:Background Perioperative stroke is a known complication in patients undergoing surgical clipping of cerebral aneurysms. Objective To evaluate whether intraoperative changes in Somatosensory-Evoked Potential (SSEP) monitoring during cerebral aneurysm clipping is diagnostic of perioperative stroke. Methods An electronic search of PubMed, Embase, and Web of Science databases was done for studies published through May 2015 on SSEP monitoring in cerebral aneurysm clipping for predicting postoperative outcomes. All titles and abstracts were screened independently on the basis of predetermined criteria. Inclusion criteria included randomized clinical trials and prospective or retrospective cohort reviews; patients with intracranial aneurysms who underwent surgical clipping with intra-operative SSEP monitoring and postoperative neurologic assessment; studies published in English on adult humans ≥18 years with sample size of ≥50; and studies inclusive of an abstract with adequate details on outcomes. Results A total of 14 articles with a sample population of 2015 patients were analyzed. SSEP monitoring demonstrated a strong mean specificity of 84.5% (95% confidence interval [95% CI] −76.3 to 90.3) but weaker sensitivity of 56.8% (95% CI 44.1−68.6) for predicting stroke. A diagnostic odds ratio of 7.772 (95% CI 5.133−11.767) suggested that the odds of observing an SSEP change among those with a postoperative neurologic deficit were 7 times greater than those without a neurologic deficit. Conclusion Intraoperative SSEP monitoring is highly specific for predicting neurologic outcome after cerebral aneurysm clipping. Patients with postoperative neurologic deficits are 7 times more likely to have had intraoperative SSEP changes. SSEP monitoring may help design prevention strategies to reduce stroke rates after cerebral aneurysm clipping.
Jeffrey Balzer - One of the best experts on this subject based on the ideXlab platform.
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abstract tp80 improving perioperative stroke detection during intracranial aneurysm surgery using Somatosensory Evoked Potential waveform analysis
Stroke, 2018Co-Authors: Eyad E Saca, Ahmed Kashkoush, Donald J Crammond, Jeffrey Balzer, Parthasarathy D ThirumalaAbstract:Background: Current alarm criteria for evaluating impending perioperative stroke using Somatosensory Evoked Potential (SSEP) intraoperative monitoring is a 50% reduction in amplitude or a 10% incre...
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diagnostic accuracy of combined multimodality Somatosensory Evoked Potential and transcranial motor Evoked Potential intraoperative monitoring in patients with idiopathic scoliosis
Spine, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Karthy Thiagarajan, Jessie Huang, Hannah Cheng, Donald J CrammondAbstract:STUDY DESIGN: Systematic review. OBJECTIVE: The aim of the study was to determine the predictive value of combined multimodality Somatosensory Evoked Potential (SSEP) and transcranial motor Evoked Potential (TcMEP) monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: The diagnostic of motor Evoked Potential monitoring and SSEP monitoring have been established. However, the predictive value of combined multimodality SSEP and TcMEP monitoring in detecting impending neurological injury during surgery for idiopathic scoliosis has not been evaluated. METHODS: A systematic literature search was performed using PubMed/MEDLINE, Web of Science, and EMBASE from 1974 to January 2015. All titles and abstracts were independently reviewed by the authors. We included all studies that were (1) randomized controlled trials, prospective or retrospective cohort studies; (2) included patients with idiopathic scoliosis undergoing scoliosis correction surgery; (3) included multimodality SSEP and TcMEP monitoring during spinal surgery; (4) included immediate postoperative neurological assessment; (5) idiopathic scoliosis patient population n ≥25; and (6) published in English. RESULTS: Seven studies comprising a total of 2052 patients with idiopathic scoliosis were included in our meta-analysis. The incidence of neurological deficit in this cohort was 0.93%. The pooled sensitivity, specificity, and Diagnostic Odds Ratio were 82.6% (95% CI 56.7%-94.5%), 94.4% (95% CI 85.1%-98.0%), and 106.16 (95% CI 24.952-451.667), respectively. The area under the curve was 0.928, indicating excellent discriminatory ability. CONCLUSION: Idiopathic scoliosis corrective surgery patients who experience a new neurological deficit are 106.16 times more likely to have had an SSEP and/or TcMEP change during corrective procedures. The results of this meta-analysis demonstrate that combined multimodality SSEP and TcMEP monitoring possess some advantage over use of each alone, and that intraoperative neurophysiological monitoring may provide a valuable biomarker in detection of impending neurological injury. LEVEL OF EVIDENCE: 2.
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diagnostic accuracy of Somatosensory Evoked Potential monitoring during scoliosis fusion
Journal of Clinical Neuroscience, 2016Co-Authors: Parthasarathy D Thirumala, Jeffrey Balzer, Hannah L Cheng, Yoon K Loke, Kojo D Hamilton, Donald J CrammondAbstract:The goal of this review was to ascertain the diagnostic accuracy of intraoperative Somatosensory Evoked Potential (SSEP) changes to predict perioperative neurological outcome in patients undergoing spinal deformity surgery to correct adolescent idiopathic scoliosis (AIS). The authors searched PubMed/MEDLINE and World Science databases to retrieve reports and/or experiments from January 1950 through January 2014 for studies on SSEP use during AIS surgery. All motor and sensory deficits were noted in the neurological examination administered after the procedure which was used to determine the effectiveness of SSEP as an intraoperative monitoring technique. Fifteen studies identified a total of 4763 procedures on idiopathic patients. The observed incidence of neurological deficits was 1.11% (53/4763) of the sample population. Of the patients with new postoperative neurological deficits 75.5% (40/53) showed significant SSEP changes, and 24.5% (13/53) did not show significant change. Pooled analysis using the bivariate model showed SSEP change with pooled sensitivity (average 84%, 95% confidence interval 59-95%) and specificity (average 98%, 95% confidence interval 97-99%). The diagnostic odds ratio of a patient who had a new neurological deficit with SSEP changes was a diagnostic odds ratio of 340 (95% confidence interval 125-926). Overall, detection of SSEP changes had excellent discriminant ability with an area under the curve of 0.99. Our meta-analysis covering 4763 operations on idiopathic patients showed that it is a highly sensitive and specific test and that iatrogenic spinal cord injury resulting in new neurological deficits was 340 times more likely to have changes in SSEP compared to those without any new deficits.
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diagnostic value of Somatosensory Evoked Potential monitoring during cerebral aneurysm clipping a systematic review
World Neurosurgery, 2016Co-Authors: Parthasarathy D Thirumala, Donald J Crammond, Reshmi Udesh, Aditya Muralidharan, Karthy Thiagarajan, Yuefang Chang, Jeffrey BalzerAbstract:Background Perioperative stroke is a known complication in patients undergoing surgical clipping of cerebral aneurysms. Objective To evaluate whether intraoperative changes in Somatosensory-Evoked Potential (SSEP) monitoring during cerebral aneurysm clipping is diagnostic of perioperative stroke. Methods An electronic search of PubMed, Embase, and Web of Science databases was done for studies published through May 2015 on SSEP monitoring in cerebral aneurysm clipping for predicting postoperative outcomes. All titles and abstracts were screened independently on the basis of predetermined criteria. Inclusion criteria included randomized clinical trials and prospective or retrospective cohort reviews; patients with intracranial aneurysms who underwent surgical clipping with intra-operative SSEP monitoring and postoperative neurologic assessment; studies published in English on adult humans ≥18 years with sample size of ≥50; and studies inclusive of an abstract with adequate details on outcomes. Results A total of 14 articles with a sample population of 2015 patients were analyzed. SSEP monitoring demonstrated a strong mean specificity of 84.5% (95% confidence interval [95% CI] −76.3 to 90.3) but weaker sensitivity of 56.8% (95% CI 44.1−68.6) for predicting stroke. A diagnostic odds ratio of 7.772 (95% CI 5.133−11.767) suggested that the odds of observing an SSEP change among those with a postoperative neurologic deficit were 7 times greater than those without a neurologic deficit. Conclusion Intraoperative SSEP monitoring is highly specific for predicting neurologic outcome after cerebral aneurysm clipping. Patients with postoperative neurologic deficits are 7 times more likely to have had intraoperative SSEP changes. SSEP monitoring may help design prevention strategies to reduce stroke rates after cerebral aneurysm clipping.
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intraoperative Somatosensory Evoked Potential monitoring during anterior cervical discectomy and fusion in nonmyelopathic patients a review of 1 039 cases
The Spine Journal, 2007Co-Authors: Patrick N Smith, Donald J Crammond, Jeffrey Balzer, R J Sclabassi, Mustafa H Khan, William C Welch, Peter C Gerszten, James D Kang, Rick Davis, William F DonaldsonAbstract:Abstract Background context Intraoperative Somatosensory Evoked Potential (SSEP) monitoring has been shown to reduce the incidence of new postoperative neurological deficits in scoliosis surgery. However, its usefulness during cervical spine surgery remains a subject of debate. Purpose To determine the utility of intraoperative SSEP monitoring in a specific patient population (those with cervical radiculopathy in the absence of myelopathy) who underwent anterior cervical discectomy and fusion (ACDF) surgery. Study design Retrospective review. Patient sample A total of 1,039 nonmyelopathic patients who underwent single or multilevel ACDF surgery. The control group (462 patients) did not have intraoperative SSEP monitoring, whereas the monitored group (577 patients) had continuous intraoperative SSEP monitoring performed. Outcome measure A new postoperative neurological deficit. Methods SSEP tracings were reviewed for all 577 patients in the monitored group and all significant signal changes were noted. Medical records were reviewed for all 1,039 patients to determine if any new neurological deficits developed in the immediate postoperative period. Results None of the patients in the control group had any new postoperative neurological deficits. In the monitored group there were six instances of transient SSEP changes (1 due to suspected carotid artery compression; 5 thought to be due to transient hypotension) which resolved with the appropriate intraoperative intervention (repositioning of retractors; raising the arterial blood pressure). Upon waking up from anesthesia, one patient in the monitored group had a new neurological deficit (partial central cord syndrome) despite normal intraoperative SSEP signals. Conclusions ACDF appears to be a safe surgical procedure with a low incidence of iatrogenic neurological injury. Transient SSEP signal changes, which improved with intraoperative interventions, were not associated with new postoperative neurological deficits. An intraoperative neurological deficit is possible despite normal SSEP signals.
Yong Hu - One of the best experts on this subject based on the ideXlab platform.
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An Intelligent Decision System for Intraoperative Somatosensory Evoked Potential Monitoring
IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2016Co-Authors: Han-xiong Li, Yong HuAbstract:Somatosensory Evoked Potential (SEP) is a useful, noninvasive technique widely used for spinal cord monitoring during surgery. One of the main indicators of a spinal cord injury is the drop in amplitude of the SEP signal in comparison to the nominal baseline that is assumed to be constant during the surgery. However, in practice, the real-time baseline is not constant and may vary during the operation due to nonsurgical factors, such as blood pressure, anaesthesia, etc. Thus, a false warning is often generated if the nominal baseline is used for SEP monitoring. In current practice, human experts must be used to prevent this false warning. However, these well-trained human experts are expensive and may not be reliable and consistent due to various reasons like fatigue and emotion. In this paper, an intelligent decision system is proposed to improve SEP monitoring. First, the least squares support vector regression and multi-support vector regression models are trained to construct the dynamic baseline from historical data. Then a control chart is applied to detect abnormalities during surgery. The effectiveness of the intelligent decision system is evaluated by comparing its performance against the nominal baseline model by using the real experimental datasets derived from clinical conditions.
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A dynamic prediction model for intraoperative Somatosensory Evoked Potential monitoring
2015 IEEE International Conference on Computational Intelligence and Virtual Environments for Measurement Systems and Applications (CIVEMSA), 2015Co-Authors: Shengpu Xu, Yong HuAbstract:This study proposed a support vector regression model applied in prediction of intraoperative Somatosensory Evoked Potential changes associated with physiological and anesthetic changes. This model was developed from probability distribution and support vector machines. The predicted results showed that observed and predicted SEP has similar variation trend with different values, with acceptable errors. With this prediction model, changes of SEP in correlation with non-surgical factors were estimated. Not only the prediction accuracy of SEP has been improved, but also provides the reliability of the classification. It will be helpful to develop an intelligent monitor model based expert system that can make a reliable decision for the Potential spinal injury.
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comparison of blind source separation methods in fast Somatosensory Evoked Potential detection
Journal of Clinical Neurophysiology, 2011Co-Authors: Chunqi Chang, Yong HuAbstract:Abstract Blind source separation (BSS) is a promising method for extracting Somatosensory-Evoked Potential (SEP). Although various BSS algorithms are available for SEP extraction, few studies have addressed the performance differences between them. In this study, we compared the performance of a number of typical BSS algorithms on SEP extraction from both computer simulations and clinical experiment. The algorithms we compared included second-order blind identification, estimation of signal parameters via rotation invariance technique, algorithm for multiple unknown signals extraction, joint approximate diagonalization of eigenmatrices, extended infomax, and fast independent component analysis. The performances of these BSS algorithms were determined by the correlation coefficients between the true and the extracted SEP signals. There were significant differences in the performances of the various BSS algorithms in a simulation study. In summary, second-order blind identification using six covariance matrix denoting SOBI6 was recommended as the most appropriate BSS method for fast SEP extraction from noisy backgrounds.
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Fast extraction of Somatosensory Evoked Potential based on Second Order Blind Identification
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007Co-Authors: Yong Hu, Cq ChangAbstract:Second order blind identification (SOBI) technique is a promising independent component analysis (ICA) method to extract Somatosensory Evoked Potential (SEP). This simulation study focused on SEP extraction from EEG and power-line noise contaminated SEP signals at signal to noise ratio (SNR) of -10 dB and -20 dB. The correlation coefficients between template SEP and SOBI extracted SEP showed significant high similarity (r>0.76) at -10 dB and mild acceptable similarity (r>0.6) at -20 dB EEG contaminated SEP. However, SOBI extracted SEP showed good performance in power-line noise situation to achieve high correlation coefficients with template SEP (r=0.96). The fast extracted SEP showed stable amplitude and latency, which are almost identical with the SEP template. The results suggested that SOBI is an appropriate method to extract SEP from noisy background.
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adaptive signal enhancement of Somatosensory Evoked Potential for spinal cord compression detection an experimental study
Computers in Biology and Medicine, 2005Co-Authors: Yong Hu, Chunqi Chang, F H Y Chan, W W LuAbstract:The objective of this study was to assess the efficacy of adaptive signal enhancement (ASE) as a means of indicating intraoperative spinal cord impingement. ASE technique was used to determine the changes in the Somatosensory Evoked Potential (SEP) elicited from eighteen rats with varying levels of spinal cord compression. ASE technique was found to be able to effectively extract SEP signals for the detection of spinal cord injury. Furthermore, while the traditional ensemble averaging (EA) technique requires more than 500 trials for meaningful signal processing in severe noisy SEP recordings, the ASE method required only 50 trials to provide similar information. Because of its fast and reliable SEP detection, the ASE method is ideal for spinal cord monitoring in the clinical setting.
Todd J. Albert - One of the best experts on this subject based on the ideXlab platform.
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comparison of transcranial electric motor and Somatosensory Evoked Potential monitoring during cervical spine surgery
Journal of Bone and Joint Surgery American Volume, 2004Co-Authors: Alan S. Hilibrand, Daniel M Schwartz, Venkat Sethuraman, Alexander R Vaccaro, Todd J. AlbertAbstract:Background: There has been little enthusiasm for Somatosensory Evoked Potential monitoring in cervical spine surgery as a result, in part, of the increased risk of motor tract injury at this level, to which Somatosensory monitoring may be insensitive. Transcranial electric motor Evoked Potential monitoring allows assessment of the motor tracts; therefore, we compared transcranial electric motor Evoked Potential and Somatosensory Evoked Potential monitoring during cervical spine surgery to determine the temporal relationship between the changes in the Potentials demonstrated by each type of monitoring and neurological sequelae and to identify patient-related and surgical factors associated with intraoperative neurophysiological changes. Methods: Somatosensory Evoked Potential and transcranial electric motor Evoked Potential data recorded for 427 patients undergoing anterior or posterior cervical spine surgery between January 1999 and March 2001 were analyzed. All patients who showed substantial (at least 60%) or complete unilateral or bilateral amplitude loss, for at least ten minutes, during the transcranial electric motor Evoked Potential and/or Somatosensory Evoked Potential monitoring were identified. Results: Twelve of the 427 patients demonstrated substantial or complete loss of amplitude of the transcranial electric motor Evoked Potentials. Ten of those patients had complete reversal of the loss following prompt intraoperative intervention, whereas two awoke with a new motor deficit. Somatosensory Evoked Potential monitoring failed to identify any change in one of the two patients, and the change in the Somatosensory Evoked Potentials lagged behind the change in the transcranial electric motor Evoked Potentials by thirty-three minutes in the other. No patient showed loss of amplitude of the Somatosensory Evoked Potentials in the absence of changes in the transcranial electric motor Evoked Potentials. Transcranial electric motor Evoked Potential monitoring was 100% sensitive and 100% specific, whereas Somatosensory Evoked Potential monitoring was only 25% sensitive; it was, however, 100% specific. Conclusions: Transcranial electric motor Evoked Potential monitoring appears to be superior to conventional Somatosensory Evoked Potential monitoring for identifying evolving motor tract injury during cervical spine surgery. Surgeons should strongly consider using this modality when operating on patients with cervical spondylotic myelopathy in general and on those with ossification of the posterior longitudinal ligament in particular. Level of Evidence: Diagnostic study, Level I-1 (testing of previously developed diagnostic criteria in series of consecutive patients [with universally applied reference “gold” standard]). See Instructions to Authors for a complete description of levels of evidence.