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Michalopoulos, Giorgos D.

https://orcid.org/0000-0002-7473-7262

Mayo Clinic

Mayo Clinic

Citations 63

Semispinalis Cervicis Sarcopenia is Associated With Worsening Cervical Sagittal Balance and Junctional Alignment Following Posterior Cervical Fusion for Myelopathy
Pinter, Zachariah W. , Townsley, Sarah, Omar, Adan, Michalopoulos, Giorgos D. , Freedman, Brett A. , Currier, Bradford L. , Elder, Benjamin D. , Bydon, Mohamad , Fogelson, Jeremy L. , Sebastian, Arjun S. , Fogelson, Jeremy, Michalopoulos, Giorgos , Salmons, Harold I. , Nassr, Ahmad

Clinical Spine Surgery | August 9, 2022 | Volume: 36 | Issue: 7 | Pages: E288-E293

10.1097/bsd.0000000000001366 Get It

Study Design: This was a retrospective cohort study. Objective: The present study is the first to investigate whether cervical paraspinal sarcopenia is associated with cervicothoracic sagittal alignment parameters after posterior cervical fusion (PCF). Summary of Background Data: Few studies have investigated the association between sarcopenia and postoperative outcomes after cervical spine surgery. Methods: We retrospectively reviewed patients undergoing PCF from C2–T2 at a single institution between the years 2017–2020. Two independent reviewers utilized axial cuts of T2-weighted magnetic resonance imaging sequences to perform Goutallier classification of the bilateral semispinalis cervicis (SSC) muscles. Cervical sagittal alignment parameters were compared between subgroups based upon severity of SSC sarcopenia. Results: We identified 61 patients for inclusion in this study, including 19 patients with mild SSC sarcopenia and 42 patients with moderate or severe SSC sarcopenia. The moderate-severe sarcopenia subgroup demonstrated a significantly larger change in C2–C7 sagittal vertical axis (+6.8 mm) from the 3-month to 1-year postoperative follow-up in comparison to the mild sarcopenia subgroup (−2.0 mm; P=0.02). The subgroup of patients with moderate-severe sarcopenia also demonstrated an increase in T1–T4 kyphosis (10.9–14.2, P=0.007), T1 slope (28.2–32.4, P=0.003), and C2 slope (24.1–27.3, P=0.05) from 3-month to 1-year postoperatively and a significant decrease in C1-occiput distance (6.3–4.1, P=0.002) during this same interval. Conclusions: In a uniform cohort of patients undergoing PCF from C2–T2, SSC sarcopenia was associated with worsening cervicothoracic alignment from 3-month to 1-year postoperatively.
Rescue therapy with novel waveform spinal cord stimulation for patients with failed back surgery syndrome refractory to conventional stimulation: a systematic review and meta-analysis
Sammak, Sally El , Michalopoulos, Giorgos D. , Romero, Joshua , Ha, Christopher T., Bydon, Mohamad , Mualem, William , Hunt, Christine L., Michalopoulos, Giorgos , Hunt, Christine

Journal of Neurosurgery: Spine | June 24, 2022 | Volume: 37 | Issue: 5 | Pages: 670-679

10.3171/2022.4.spine22331 Get It

OBJECTIVE Conventional spinal cord stimulators (SCSs) have demonstrated efficacy in individuals with failed back surgery syndrome (FBSS). However, a subgroup of patients may become refractory to the effects of conventional waveforms over time. The objective of this study was to systematically review and evaluate the current literature on the use of novel waveform spinal cord stimulation for the management of FBSS refractory to conventional SCSs. METHODS A comprehensive electronic search of the literature published in electronic databases, including Ovid MEDLINE and Epub Ahead of Print, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus, was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The outcomes of interest were reduction in back pain and/or leg pain after conversion from conventional to novel SCSs. Risk of bias was assessed with the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) tool. The strength of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria. RESULTS A total of 6 studies with 137 patients with FBSS were identified. Studies were published between 2013 and 2021. The mean ± SD age of the pooled patient sample was 55 ± 10.5 years. All patients who underwent treatment with conventional SCSs were identified. Two studies evaluated the efficacy of high-density spinal cord stimulation, 3 studies evaluated burst spinal cord stimulation, and 1 study assessed multimodal waveforms. The mean difference in back pain scores after conversion from a standard SCS to a novel waveform SCS was 2.55 (95% CI 1.59–4.08), demonstrating a significant reduction in back pain after conversion to novel stimulation. The authors also performed a subgroup analysis to compare burst stimulation to tonic waveforms. In this analysis, the authors found no significant difference in the average reductions in back pain between the 2 groups (p = 0.534).The authors found an I2 statistic equivalent to 98.47% in the meta-regression model used to assess the effect of follow-up duration on study outcome; this value implied that the variability in the data can be attributed to the remaining between-study heterogeneity. The overall certainty was moderate, with a high risk of bias across studies. CONCLUSIONS Rescue therapy with novel waveform spinal cord stimulation is a potential option for pain reduction in patients who become refractory to conventional SCSs. Conversion to novel waveform SCSs may potentially mitigate expenses and complications.
Positive impact of the pandemic: the effect of post–COVID-19 virtual visit implementation on departmental efficiency and patient satisfaction in a quaternary care center
Pennington, Zach , Michalopoulos, Giorgos D. , Biedermann, Aaron, Ziegler, Jeffrey R., Durst, Sherri L., Spinner, Robert J. , Meyer, Fredric B. , Bydon, Mohamad , Pennington, Zach , Michalopoulos, Giorgos , Ziegler, Jeff R., Daniels, David J.

Neurosurgical Focus | June 1, 2022 | Volume: 52 | Issue: 6 | Pages: E10

10.3171/2022.3.focus2243 Get It

OBJECTIVE The coronavirus disease 2019 (COVID-19) pandemic has significantly changed clinical practice across US healthcare. Increased adoption of telemedicine has emerged as an alternative to in-person contact for patient-physician interactions. The aim of this study was to analyze the impact of telemedicine on workflow and care delivery from January 2019 to December 2021 in a neurosurgical department at a quaternary care center. METHODS Prospectively captured data on clinic appointment utilization, duration, and outcomes were queried. Visits were divided into in-person visits and telemedicine appointments, categorized as follow-up visits of previously surgically treated patients, internal consultations, new patient visits, and early postoperative returns after surgery. Appointment volume was compared pre- and postpandemic using March 2020 as the pandemic onset. Clinical efficiency was measured by time to appointment, rate of on-time appointments, proportion of appointments resulting in surgical intervention (surgical yield), and patient-reported satisfaction, the latter measured as the proportion of patients indicating “high likelihood to recommend practice.” RESULTS A total of 54,562 visits occurred, most commonly for follow-up for previously operated patients (51.8%), internal new patient referrals (24.5%), and external new patient referrals (19.8%). Total visit volume was stable pre- to postpandemic (1521.3 vs 1512, p = 0.917). However, in-person visits significantly decreased (1517/month vs 1220/month, p < 0.001), with a nadir in April 2020, while telemedicine appointment utilization increased significantly (0.3% vs 19.1% of all visits). Telemedicine utilization remained stable throughout the 1st calendar year following the pandemic. Telemedicine appointments were associated with shorter time to appointment than in-person visits both before and after the pandemic onset (0–5 days from appointment request: 60% vs 33% vs 29.8%, p < 0.001). Patients had on-time appointments in 87% of telemedicine encounters. Notably, telemedicine appointments resulted in surgery in 31.8% of internal consultations or new patient visits, a significantly lower rate than that for in-person visits (51.8%). After the widespread integration of telemedicine, patient satisfaction for all visits was higher than before the pandemic onset (85.9% vs 88.5%, p = 0.027). CONCLUSIONS Telemedicine use significantly increased following the pandemic onset, compensating for observed decreases in face-to-face visits. Utilization rates have remained stable, suggesting effective integration, and delays between referrals and appointments were lower than for in-person visits. Importantly, telemedicine integration was not associated with a decrease in overall patient satisfaction, although telemedicine appointments had a lower surgical yield. These data suggest that telemedicine smoothened the impact of the pandemic on clinical workflow and helped to maintain continuity and quality of outpatient care.
Outpatient versus inpatient lumbar decompression surgery: a matched noninferiority study investigating clinical and patient-reported outcomes
Mooney, James , Michalopoulos, Giorgos D. , Zeitouni, Daniel , Sammak, Sally El , Alvi, Mohammed Ali , Wang, Michael Y. , Coric, Domagoj , Chan, Andrew K. , Mummaneni, Praveen V. , Bisson, Erica F. , Sherrod, Brandon A. , Haid, Regis W., Knightly, John J. , Devin, Clinton J. , Pennicooke, Brenton , Asher, Anthony L. , Bydon, Mohamad , Alvi, Mohammed Ali , Michalopoulos, Giorgos

Journal of Neurosurgery: Spine | May 13, 2022 | Volume: 37 | Issue: 4 | Pages: 485-497

10.3171/2022.3.spine211558 Get It

OBJECTIVE Spine surgery represents an ideal target for healthcare cost reduction efforts, with outpatient surgery resulting in significant cost savings. With an increased focus on value-based healthcare delivery, lumbar decompression surgery has been increasingly performed in the outpatient setting when appropriate. The aim of this study was to compare clinical and patient-reported outcomes following outpatient and inpatient lumbar decompression surgery. METHODS The Quality Outcomes Database (QOD) was queried for patients undergoing elective one- or two-level lumbar decompression (laminectomy or laminotomy with or without discectomy) for degenerative spine disease. Patients were grouped as outpatient if they had a length of stay (LOS) < 24 hours and as inpatient if they stayed in the hospital ≥ 24 hours. Patients with ≥ 72-hour stay were excluded from the comparative analysis to increase baseline comparability between the two groups. To create two highly homogeneous groups, optimal matching was performed at a 1:1 ratio between the two groups on 38 baseline variables, including demographics, comorbidities, symptoms, patient-reported scores, indications, and operative details. Outcomes of interest were readmissions and reoperations at 30 days and 3 months after surgery, overall satisfaction, and decrease in Oswestry Disability Index (ODI), back pain, and leg pain at 3 months after surgery. Satisfaction was defined as a score of 1 or 2 in the North American Spine Society patient satisfaction index. Noninferiority of outpatient compared with inpatient surgery was defined as risk difference of < 1.5% at a one-sided 97.5% confidence interval. RESULTS A total of 18,689 eligible one- and two-level decompression surgeries were identified. The matched study cohorts consisted of 5016 patients in each group. Nonroutine discharge was slightly less common in the outpatient group (0.6% vs 0.3%, p = 0.01). The 30-day readmission rates were 4.4% and 4.3% for the outpatient and inpatient groups, respectively, while the 30-day reoperation rates were 1.4% and 1.5%. The 3-month readmission rates were 6.3% for both groups, and the 3-month reoperation rates were 3.1% for the outpatient cases and 2.9% for the inpatient cases. Overall satisfaction at 3 months was 88.8% for the outpatient group and 88.4% for the inpatient group. Noninferiority of outpatient surgery was documented for readmissions, reoperations, and patient-reported satisfaction from surgery. CONCLUSIONS Outpatient lumbar decompression surgery demonstrated slightly lower nonroutine discharge rates in comparison with inpatient surgery. Noninferiority in clinical outcomes at 30 days and 3 months after surgery was documented for outpatient compared with inpatient decompression surgery. Additionally, outpatient decompression surgery performed noninferiorly to inpatient surgery in achieving patient satisfaction from surgery.
Letter to the Editor. Randomized controlled trials on surgical decision-making
Michalopoulos, Giorgos D., Nathani, Karim Rizwan, Bydon, Mohamad, Michalopoulos, Giorgos D. , Michalopoulos, Giorgos , Nathani, Karim Rizwan, Bydon, Mohamad

Journal of Neurosurgery: Spine | April 1, 2022 | Volume: 37 | Issue: 3 | Pages: 467-469

10.3171/2022.1.spine211566 Get It

Commentary: The Legal and Socioeconomic Considerations in Spine Telemedicine
Bydon, Mohamad , Michalopoulos, Giorgos D. , Michalopoulos, Giorgos , Bydon, Mohamad

Neurosurgery | March 3, 2022 | Volume: 90 | Issue: 5 | Pages: e125-e126

10.1227/neu.0000000000001918 Get It

Factors associated with progression and mortality among patients undergoing stereotactic radiosurgery for intracranial metastasis: results from a national real-world registry
Alvi, Mohammed Ali, Asher, Anthony L., Michalopoulos, Giorgos D., Grills, Inga S., Warnick, Ronald E., McInerney, James, Chiang, Veronica L., Attia, Albert, Timmerman, Robert, Chang, Eric, Kavanagh, Brian D., Andrews, David W., Walter, Kevin, Bydon, Mohamad, Sheehan, Jason P., Warnick, Ronald E. , Alvi, Mohammed Ali , Michalopoulos, Giorgos D. , Alvi, Mohammed Ali , Michalopoulos, Giorgos , Alvi, Mohammed Ali, Asher, Anthony L., Grills, Inga S., Warnick, Ronald E., McInerney, James, Chiang, Veronica L., Attia, Albert, Timmerman, Robert, Chang, Eric, Kavanagh, Brian D., Andrews, David W., Walter, Kevin, Bydon, Mohamad, Sheehan, Jason P.

Journal of Neurosurgery | January 21, 2022 | Volume: 137 | Issue: 4 | Pages: 985-998

10.3171/2021.10.jns211410 Get It

OBJECTIVE Stereotactic radiosurgery (SRS) has been increasingly employed in recent years to treat intracranial metastatic lesions. However, there is still a need for optimization of treatment paradigms to provide better local control and prevent progressive intracranial disease. In the current study, the authors utilized a national collaborative registry to investigate the outcomes of patients with intracranial metastatic disease who underwent SRS and to determine factors associated with lesion treatment response, overall progression, and mortality. METHODS The NeuroPoint Alliance SRS registry was queried for all patients with intracranial metastatic lesions undergoing single- or multifraction SRS at participating institutions between 2016 and 2020. The main outcomes of interest included lesion response (lesion-level analysis), progression using Response Assessment for Neuro-Oncology criteria, and mortality (patient-level analysis). Kaplan-Meier analysis was used to report time to progression and overall survival, and multivariable Cox proportional hazards analysis was used to investigate factors associated with lesion response, progression, and mortality. RESULTS A total of 501 patients (1447 intracranial metastatic lesions) who underwent SRS and had available follow-up were included in the current analyses. The most common primary tumor was lung cancer (49.5%, n = 248), followed by breast (15.4%, n = 77) and melanoma (12.2%, n = 61). Most patients had a single lesion (44.9%, n = 225), 29.3% (n = 147) had 2 or 3 lesions, and 25.7% (n = 129) had > 3 lesions. The mean sum of baseline measurements of the lesions according to Response Evaluation Criteria in Solid Tumors (RECIST) was 35.54 mm (SD 25.94). At follow-up, 671 lesions (46.4%) had a complete response, 631 (43.6%) had a partial response (≥ 30% decrease in longest diameter) or were stable (< 30% decrease but < 20% increase), and 145 (10%) showed progression (> 20% increase in longest diameter). On multivariable Cox proportional hazards analysis, melanoma-associated lesions (HR 0.48, 95% CI 0.34–0.67; p < 0.001) and larger lesion size (HR 0.94, 95% CI 0.93–0.96; p < 0.001) showed lower odds of lesion regression, while a higher biologically effective dose was associated with higher odds (HR 1.001, 95% CI 1.0001–1.00023; p < 0.001). A total of 237 patients (47.3%) had overall progression (local failure or intracranial progressive disease), with a median time to progression of 10.03 months after the index SRS. Factors found to be associated with increased hazards of progression included male sex (HR 1.48, 95% CI 1.108–1.99; p = 0.008), while administration of immunotherapy (before or after SRS) was found to be associated with lower hazards of overall progression (HR 0.62, 95% CI 0.460–0.85; p = 0.003). A total of 121 patients (23.95%) died during the follow-up period, with a median survival of 19.4 months from the time of initial SRS. A higher recursive partitioning analysis score (HR 21.3485, 95% CI 1.53202–3.6285; p < 0.001) was found to be associated with higher hazards of mortality, while single-fraction treatment compared with hypofractionated treatment (HR 0.082, 95% CI 0.011–0.61; p = 0.015), administration of immunotherapy (HR 0.385, 95% CI 0.233–0.64; p < 0.001), and presence of single compared with > 3 lesions (HR 0.427, 95% CI 0.187–0.98; p = 0.044) were found to be associated with lower risk of mortality. CONCLUSIONS The comparability of results between this study and those of previously published clinical trials affirms the value of multicenter databases with real-world data collected without predetermined research purpose.
Minimally invasive versus open lumbar spinal fusion: a matched study investigating patient-reported and surgical outcomes
Mooney, James , Michalopoulos, Giorgos D. , Alvi, Mohammed Ali , Zeitouni, Daniel , Chan, Andrew K. , Mummaneni, Praveen V. , Bisson, Erica F. , Sherrod, Brandon A. , Haid, Regis W., Knightly, John J. , Devin, Clinton J. , Pennicooke, Brenton , Asher, Anthony L. , Bydon, Mohamad , Alvi, Mohammed Ali , Michalopoulos, Giorgos

Journal of Neurosurgery: Spine | December 31, 2021 | Volume: 36 | Issue: 5 | Pages: 753-766

10.3171/2021.10.spine211128 Get It

OBJECTIVE With the expanding indications for and increasing popularity of minimally invasive surgery (MIS) for lumbar spinal fusion, large-scale outcomes analysis to compare MIS approaches with open procedures is warranted. METHODS The authors queried the Quality Outcomes Database for patients who underwent elective lumbar fusion for degenerative spine disease. They performed optimal matching, at a 1:2 ratio between patients who underwent MIS and those who underwent open lumbar fusion, to create two highly homogeneous groups in terms of 33 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, indications, and operative details). The outcomes of interest were overall satisfaction, decrease in Oswestry Disability Index (ODI), and back and leg pain, as well as hospital length of stay (LOS), operative time, reoperations, and incidental durotomy rate. Satisfaction was defined as a score of 1 or 2 on the North American Spine Society scale. Minimal clinically important difference (MCID) in ODI was defined as ≥ 30% decrease from baseline. Outcomes were assessed at the 3- and 12-month follow-up evaluations. RESULTS After the groups were matched, the MIS and open groups consisted of 1483 and 2966 patients, respectively. Patients who underwent MIS fusion had higher odds of satisfaction at 3 months (OR 1.4, p = 0.004); no difference was demonstrated at 12 months (OR 1.04, p = 0.67). Lumbar stenosis, single-level fusion, higher American Society of Anesthesiologists Physical Status Classification System grade, and absence of spondylolisthesis were most prominently associated with higher odds of satisfaction with MIS compared with open surgery. Patients in the MIS group had slightly lower ODI scores at 3 months (mean difference 1.61, p = 0.006; MCID OR 1.14, p = 0.0495) and 12 months (mean difference 2.35, p < 0.001; MCID OR 1.29, p < 0.001). MIS was also associated with a greater decrease in leg and back pain at both follow-up time points. The two groups did not differ in operative time and incidental durotomy rate; however, LOS was shorter for the MIS group. Revision surgery at 12 months was less likely for patients who underwent MIS (4.1% vs 5.6%, p = 0.032). CONCLUSIONS In patients who underwent lumbar fusion for degenerative spinal disease, MIS was associated with higher odds of satisfaction at 3 months postoperatively. No difference was demonstrated at the 12-month follow-up. MIS maintained a small, yet consistent, superiority in decreasing ODI and back and leg pain, and MIS was associated with a lower reoperation rate.
Time trend analysis of database and registry use in the neurosurgical literature: evidence for the advance of registry science
Asher, Anthony L. , Sammak, Sally El , Michalopoulos, Giorgos D. , Yolcu, Yagiz U. , Alexander, A. Yohan , Knightly, John J. , Foley, Kevin T. , Shaffrey, Christopher I. , Rose, Geoffrey, Coric, Domagoj , Bisson, Erica F. , Glassman, Steven D. , Mummaneni, Praveen V. , Bydon, Mohamad , Michalopoulos, Giorgos , Alexander, A Yohan , Harbaugh, Robert E. , Rose, Geoffrey A.

Journal of Neurosurgery | December 24, 2021 | Volume: 136 | Issue: 6 | Pages: 1804-1809

10.3171/2021.9.jns212153 Get It

Commentary: Predicting Clinically Relevant Patient-Reported Symptom Improvement After Carpal Tunnel Release: A Machine Learning Approach
Bydon, Mohamad , Sammak, Sally El, Michalopoulos, Giorgos D., Spinner, Robert J., Michalopoulos, Giorgos D. , Sammak, Sally El , El Sammak, Sally, Michalopoulos, Giorgos , Bydon, Mohamad , Spinner, Robert J.

Neurosurgery | December 15, 2021 | Volume: 90 | Issue: 1 | Pages: e5-e6

10.1227/neu.0000000000001750 Get It