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Michalopoulos, Giorgos D.

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

Mayo Clinic

Mayo Clinic

Citations 63

What predicts the best 24-month outcomes following surgery for cervical spondylotic myelopathy? A QOD prospective registry study
Chan, Andrew K. , Park, Christine , Shaffrey, Christopher I. , Gottfried, Oren N., Than, Khoi D. , Bisson, Erica F. , Bydon, Mohamad , Asher, Anthony L. , Coric, Domagoj , Potts, Eric A. , Foley, Kevin T. , Wang, Michael Y. , Fu, Kai-Ming, Virk, Michael S. , Knightly, John J. , Meyer, Scott A., Upadhyaya, Cheerag D., Shaffrey, Mark E., Buchholz, Avery L., Tumialán, Luis M. , Turner, Jay D. , Michalopoulos, Giorgos D. , Sherrod, Brandon A. , Chou, Dean , Haid, Regis W., Mummaneni, Praveen V. , Michalopoulos, Giorgos , Park, Paul , Agarwal, Nitin

Journal of Neurosurgery: Spine | January 5, 2024 | Volume: 40 | Issue: 4 | Pages: 453-464

10.3171/2023.11.spine23222 Get It

OBJECTIVE The aim of this study was to identify predictors of the best 24-month improvements in patients undergoing surgery for cervical spondylotic myelopathy (CSM). For this purpose, the authors leveraged a large prospective cohort of surgically treated patients with CSM to identify factors predicting the best outcomes for disability, quality of life, and functional status following surgery. METHODS This was a retrospective analysis of prospectively collected data. The Quality Outcomes Database (QOD) CSM dataset (1141 patients) at 14 top enrolling sites was used. Baseline and surgical characteristics were compared for those reporting the top and bottom 20th percentile 24-month Neck Disability Index (NDI), EuroQol-5D (EQ-5D), and modified Japanese Orthopaedic Association (mJOA) change scores. A multivariable logistic model was constructed and included candidate variables reaching p ≤ 0.20 on univariate analyses. Least important variables were removed in a stepwise manner to determine the significant predictors of the best outcomes (top 20th percentile) for 24-month NDI, EQ-5D, and mJOA change. RESULTS A total of 948 (83.1%) patients with 24-month follow-up were included in this study. For NDI, 204 (17.9%) had the best NDI outcome and 200 (17.5%) had the worst NDI outcome. Factors predicting the best NDI outcomes included symptom duration less than 12 months (OR 1.5, 95% CI 1.1–1.9; p = 0.01); procedure other than posterior fusion (OR 1.5, 95% CI 1.03–2.1; p = 0.03); higher preoperative visual analog scale neck pain score (OR 1.2, 95% CI 1.1–1.3; p < 0.001); and higher baseline NDI (OR 1.06, 95% CI 1.05–1.07; p < 0.001). For EQ-5D, 163 (14.3%) had the best EQ-5D outcome and 169 (14.8%) had the worst EQ-5D outcome. Factors predicting the best EQ-5D outcomes included arm pain–only complaints (compared to neck pain) (OR 1.9, 95% CI 1.3–2.9; p = 0.002) and lower baseline EQ-5D (OR 167.7 per unit lower, 95% CI 85.0–339.4; p < 0.001). For mJOA, 222 (19.5%) had the best mJOA outcome and 238 (20.9%) had the worst mJOA outcome. Factors predicting the best mJOA outcomes included lower BMI (OR 1.03 per unit lower, 95% CI 1.004–1.05; p = 0.02; cutoff value of ≤ 29.5 kg/m 2 ); arm pain–only complaints (compared to neck pain) (OR 1.7, 95% CI 1.1–2.5; p = 0.02); and lower baseline mJOA (OR 1.6 per unit lower, 95% CI 1.5–1.7; p < 0.001). CONCLUSIONS Compared to the worst outcomes for EQ-5D, the best outcomes were associated with patients with arm pain–only complaints. For mJOA, lower BMI and arm pain–only complaints portended the best outcomes. For NDI, those with the best outcomes had shorter symptom durations, higher preoperative neck pain scores, and less often underwent posterior spinal fusions. Given the positive impact of shorter symptom duration on outcomes, these data suggest that early surgery may be beneficial for patients with CSM.
Impact of Educational Background on Preoperative Disease Severity and Postoperative Outcomes Among Patients With Cervical Spondylotic Myelopathy
DiGiorgio, Anthony M. , Michalopoulos, Giorgos D. , Chan, Andrew K. , Shabani, Saman , Lu, Daniel C. , Wang, Michael Y. , Haid, Regis W., Knightly, John J. , Sherrod, Brandon A. , Gottfried, Oren N., Shaffrey, Christopher I. , Virk, Michael S. , Hussain, Ibrahim , Glassman, Steven D. , Shaffrey, Mark E., Foley, Kevin T. , Pennicooke, Brenton , Coric, Domagoj , Upadhyaya, Cheerag D., Potts, Eric A. , Tumialán, Luis M. , Fu, Kai-Ming, Asher, Anthony L. , Bisson, Erica F. , Chou, Dean , Bydon, Mohamad , Mummaneni, Praveen V. , Michalopoulos, Giorgos , Agarwal, Nitin , Letchuman, Vijay , Lavadi, Raj Swaroop , Goldberg, Jacob L. , Park, Paul

Clinical Spine Surgery | December 16, 2023 | Volume: 37 | Issue: 3 | Pages: E137-E146

10.1097/bsd.0000000000001557 Get It

Study Design: Retrospective review of a prospectively maintained database. Objective: Assess differences in preoperative status and postoperative outcomes among patients of different educational backgrounds undergoing surgical management of cervical spondylotic myelopathy (CSM). Summary of Background Data: Patient education level (EL) has been suggested to correlate with health literacy, disease perception, socioeconomic status (SES), and access to health care. Methods: The CSM data set of the Quality Outcomes Database (QOD) was queried for patients undergoing surgical management of CSM. EL was grouped as high school or below, graduate-level, and postgraduate level. The association of EL with baseline disease severity (per patient-reported outcome measures), symptoms >3 or ≤3 months, and 24-month patient-reported outcome measures were evaluated. Results: Among 1141 patients with CSM, 509 (44.6%) had an EL of high school or below, 471 (41.3%) had a graduate degree, and 161 (14.1%) had obtained postgraduate education. Lower EL was statistically significantly associated with symptom duration of >3 months (odds ratio=1.68), higher arm pain numeric rating scale (NRS) (coefficient=0.5), and higher neck pain NRS (coefficient=0.79). Patients with postgraduate education had statistically significantly lower Neck Disability Index (NDI) scores (coefficient=-7.17), lower arm pain scores (coefficient=−1), and higher quality-adjusted life-years (QALY) scores (coefficient=0.06). Twenty-four months after surgery, patients of lower EL had higher NDI scores, higher pain NRS scores, and lower QALY scores (P<0.05 in all analyses). Conclusions: Among patients undergoing surgical management for CSM, those reporting a lower educational level tended to present with longer symptom duration, more disease-inflicted disability and pain, and lower QALY scores. As such, patients of a lower EL are a potentially vulnerable subpopulation, and their health literacy and access to care should be prioritized.
Does diabetes affect outcome or reoperation rate after lumbar decompression or arthrodesis? A matched analysis of the Quality Outcomes Database data set
Mooney, James , Zeitouni, Daniel , Michalopoulos, Giorgos D. , Wang, Michael Y. , Coric, Domagoj , Chan, Andrew K. , Lu, Daniel C. , Sherrod, Brandon A. , Gottfried, Oren N., Shaffrey, Christopher I. , Than, Khoi D. , Hussain, Ibrahim , Virk, Michael S. , Glassman, Steven D. , Shaffrey, Mark E., Foley, Kevin T. , Chou, Dean , Slotkin, Jonathan R., Tumialán, Luis M. , Upadhyaya, Cheerag D., Potts, Eric A. , Fu, Kai-Ming, Haid, Regis W., Knightly, John J. , Mummaneni, Praveen V. , Bisson, Erica F. , Asher, Anthony L. , Bydon, Mohamad , Michalopoulos, Giorgos , Nathani, Karim Rizwan , Goldberg, Jacob L. , Agarwal, Nitin , Park, Paul

Journal of Neurosurgery: Spine | December 2, 2023 | Volume: 40 | Issue: 3 | Pages: 331-342

10.3171/2023.9.spine23522 Get It

OBJECTIVE Diabetes mellitus (DM) is a known risk factor for postsurgical and systemic complications after lumbar spinal surgery. Smaller studies have also demonstrated diminished improvements in patient-reported outcomes (PROs), with increased reoperation and readmission rates after lumbar surgery in patients with DM. The authors aimed to examine longer-term PROs in patients with DM undergoing lumbar decompression and/or arthrodesis for degenerative pathology. METHODS The Quality Outcomes Database was queried for patients undergoing elective lumbar decompression and/or arthrodesis for degenerative pathology. Patients were grouped into DM and non-DM groups and optimally matched in a 1:1 ratio on 31 baseline variables, including the number of operated levels. Outcomes of interest were readmissions and reoperations at 30 and 90 days after surgery in addition to improvements in Oswestry Disability Index, back pain, and leg pain scores and quality-adjusted life-years at 90 days after surgery. RESULTS The matched decompression cohort comprised 7836 patients (3236 [41.3] females) with a mean age of 63.5 ± 12.6 years, and the matched arthrodesis cohort comprised 7336 patients (3907 [53.3%] females) with a mean age of 64.8 ± 10.3 years. In patients undergoing lumbar decompression, no significant differences in nonroutine discharge, length of stay (LOS), readmissions, reoperations, and PROs were observed. In patients undergoing lumbar arthrodesis, nonroutine discharge (15.7% vs 13.4%, p < 0.01), LOS (3.2 ± 2.0 vs 3.0 ± 3.5 days, p < 0.01), 30-day (6.5% vs 4.4%, p < 0.01) and 90-day (9.1% vs 7.0%, p < 0.01) readmission rates, and the 90-day reoperation rate (4.3% vs 3.2%, p = 0.01) were all significantly higher in the DM group. For DM patients undergoing lumbar arthrodesis, subgroup analyses demonstrated a significantly higher risk of poor surgical outcomes with the open approach. CONCLUSIONS Patients with and without DM undergoing lumbar spinal decompression alone have comparable readmission and reoperation rates, while those undergoing arthrodesis procedures have a higher risk of poor surgical outcomes up to 90 days after surgery. Surgeons should target optimal DM control preoperatively, particularly for patients undergoing elective lumbar arthrodesis.
What factors influence surgical decision-making in anterior versus posterior surgery for cervical myelopathy? A QOD analysis
Park, Christine , Shaffrey, Christopher I. , Than, Khoi D. , Michalopoulos, Giorgos D. , Chan, Andrew K. , Bisson, Erica F. , Sherrod, Brandon A. , Asher, Anthony L. , Coric, Domagoj , Potts, Eric A. , Foley, Kevin T. , Wang, Michael Y. , Fu, Kai-Ming, Virk, Michael S. , Knightly, John J. , Meyer, Scott A., Upadhyaya, Cheerag D., Shaffrey, Mark E., Buchholz, Avery L., Tumialán, Luis M. , Turner, Jay D. , Chou, Dean , Chaudhry, Nauman S. , Haid, Regis W., Mummaneni, Praveen V. , Bydon, Mohamad , Gottfried, Oren N., El Sammak, Sally, Michalopoulos, Giorgos , Sammak, Sally El , Park, Paul , Agarwal, Nitin

Journal of Neurosurgery: Spine | November 11, 2023 | Volume: 40 | Issue: 2 | Pages: 206-215

10.3171/2023.8.spine23194 Get It

OBJECTIVE The aim of this study was to explore the preoperative patient characteristics that affect surgical decision-making when selecting an anterior or posterior operative approach in patients diagnosed with cervical spondylotic myelopathy (CSM). METHODS This was a multi-institutional, retrospective study of the prospective Quality Outcomes Database (QOD) Cervical Spondylotic Myelopathy module. Patients aged 18 years or older diagnosed with primary CSM who underwent multilevel (≥ 2-level) elective surgery were included. Demographics and baseline clinical characteristics were collected. RESULTS Of the 841 patients with CSM in the database, 492 (58.5%) underwent multilevel anterior surgery and 349 (41.5%) underwent multilevel posterior surgery. Surgeons more often performed a posterior surgical approach in older patients (mean 64.8 ± 10.6 vs 58.5 ± 11.1 years, p < 0.001) and those with a higher American Society of Anesthesiologists class (class III or IV: 52.4% vs 46.3%, p = 0.003), a higher rate of motor deficit (67.0% vs 58.7%, p = 0.014), worse myelopathy (mean modified Japanese Orthopaedic Association score 11.4 ± 3.1 vs 12.4 ± 2.6, p < 0.001), and more levels treated (4.3 ± 1.3 vs 2.4 ± 0.6, p < 0.001). On the other hand, surgeons more frequently performed an anterior surgical approach when patients were employed (47.2% vs 23.2%, p < 0.001) and had intervertebral disc herniation as an underlying pathology (30.7% vs 9.2%, p < 0.001). CONCLUSIONS The selection of approach for patients with CSM depends on patient demographics and symptomology. Posterior surgery was performed in patients who were older and had worse systemic disease, increased myelopathy, and greater levels of stenosis. Anterior surgery was more often performed in patients who were employed and had intervertebral disc herniation.
Stereotactic radiosurgery in the management of non–small cell lung cancer brain metastases: a prospective study using the NeuroPoint Alliance Stereotactic Radiosurgery Registry
Michalopoulos, Giorgos D. , Grills, Inga S., Warnick, Ronald E. , McInerney, James , Attia, Albert, Timmerman, Robert , Chang, Eric L. , D’Ambrosio, Anthony, Cobb, William S., Spalding, Aaron C., Walter, Kevin A. , Jensen, Randy L. , Bydon, Mohamad , Asher, Anthony L. , Sheehan, Jason P. , Katsos, Konstantinos, Michalopoulos, Giorgos , Katsos, Konstantinos, Andrews, David William , Cobb, William S., Pouratian, Nader

Journal of Neurosurgery | November 11, 2023 | Volume: 140 | Issue: 5 | Pages: 1223-1232

10.3171/2023.8.jns23308 Get It

OBJECTIVE The literature on non–small cell lung cancer (NSCLC) brain metastases (BMs) managed using stereotactic radiosurgery (SRS) relies mainly on single-institution studies or randomized controlled trials (RCTs). There is a literature gap on clinical and radiological outcomes of SRS for NSCLC metastases in real-world practice. The objective of this study was to benchmark mortality and progression outcomes in patients undergoing SRS for NSCLC BMs and identify risk factors for these outcomes using a national quality registry. METHODS The SRS Registry of the NeuroPoint Alliance was used for this study. This registry included patients from 16 enrolling sites who underwent SRS from 2017 to 2022. Data are prospectively collected without a prespecified research purpose. The main outcomes of this analysis were overall survival (OS), out-of-field recurrence, local progression, and intracranial progression. All time-to-event investigations included Kaplan-Meier analyses and multivariable Cox regressions. RESULTS Two hundred sixty-four patients were identified, with a mean age of 66.7 years and a female proportion of 48.5%. Most patients (84.5%) had a Karnofsky Performance Status (KPS) score of 80–100, and the mean baseline EQ-5D score was 0.539 quality-adjusted life years. A single lesion was present in 53.4% of the patients, and 29.1% of patients had 3 or more lesions. The median OS was 28.1 months, and independent predictors of mortality included no control of primary tumor (hazard ratio [HR] 2.1), KPS of 80 (HR 2.4) or lower (HR 2.4), coronary artery disease (HR 2.8), and 5 or more lesions present at the time of SRS treatment (HR 2.3). The median out-of-field progression-free survival (PFS) was 24.8 months, and the median local PFS was unreached. Intralesional hemorrhage was an independent risk factor of local progression, with an HR of 6.0. The median intracranial PFS was 14.0 months and was predicted by the number of lesions at the time of SRS (3–4 lesions, HR 2.2; 5–14 lesions, HR 2.5). CONCLUSIONS In this real-world prospective study, the authors used a national quality registry and found favorable OS in patients with NSCLC BMs undergoing SRS compared with results from previously published RCTs. The intracranial PFS was mainly driven by the emergence of new lesions rather than local progression. A greater number of lesions at baseline was associated with out-of-field progression, while intralesional hemorrhage at baseline was associated with local progression.
Three-level ACDF versus 3-level laminectomy and fusion: are there differences in outcomes? An analysis of the Quality Outcomes Database cervical spondylotic myelopathy cohort
Ambati, Vardhaan , Macki, Mohamed, Chan, Andrew K. , Michalopoulos, Giorgos D. , Le, Vivian , Jamieson, Alysha, Chou, Dean , Shaffrey, Christopher I. , Gottfried, Oren N., Bisson, Erica F. , Asher, Anthony L. , Coric, Domagoj , Potts, Eric A. , Foley, Kevin T. , Wang, Michael Y. , Fu, Kai-Ming, Virk, Michael S. , Knightly, John J. , Meyer, Scott A., Park, Paul , Upadhyaya, Cheerag D., Shaffrey, Mark E., Buchholz, Avery L., Tumialán, Luis M. , Turner, Jay D. , Sherrod, Brandon A. , Haid, Regis W., Bydon, Mohamad , Mummaneni, Praveen V. , Michalopoulos, Giorgos , Ambati, Vardhaan

Neurosurgical Focus | September 1, 2023 | Volume: 55 | Issue: 3 | Pages: E2

10.3171/2023.6.focus23295 Get It

OBJECTIVE The authors sought to compare 3-level anterior with posterior fusion surgical procedures for the treatment of multilevel cervical spondylotic myelopathy (CSM). METHODS The authors analyzed prospective data from the 14 highest enrolling sites of the Quality Outcomes Database CSM module. They compared 3-level anterior cervical discectomy and fusion (ACDF) and posterior cervical laminectomy and fusion (PCF) surgical procedures, excluding surgical procedures crossing the cervicothoracic junction. Rates of reaching the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) were compared at 24 months postoperatively. Multivariable analyses adjusted for potential confounders elucidated in univariable analysis. RESULTS Overall, 199 patients met the inclusion criteria: 123 ACDF (61.8%) and 76 PCF (38.2%) patients. The 24-month follow-up rates were similar (ACDF 90.2% vs PCF 92.1%, p = 0.67). Preoperatively, ACDF patients were younger (60.8 ± 10.2 vs 65.0 ± 10.3 years, p < 0.01), and greater proportions were privately insured (56.1% vs 36.8%, p = 0.02), actively employed (39.8% vs 22.8%, p = 0.04), and independently ambulatory (14.6% vs 31.6%, p < 0.01). Otherwise, the cohorts had equivalent baseline modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), numeric rating scale (NRS)–arm pain, NRS–neck pain, and EQ-5D scores (p > 0.05). ACDF patients had reduced hospitalization length (1.6 vs 3.9 days, p < 0.01) and a greater proportion had nonroutine discharge (7.3% vs 22.8%, p < 0.01), but they had a higher rate of postoperative dysphagia (13.5% vs 3.5%, p = 0.049). Compared with baseline values, both groups demonstrated improvements in all outcomes at 24 months (p < 0.05). In multivariable analyses, after controlling for age, insurance payor, employment status, ambulation status, and other potential clinically relevant confounders, ACDF was associated with a greater proportion of patients with maximum satisfaction on the North American Spine Society Patient Satisfaction Index (NASS) (NASS score of 1) at 24 months (69.4% vs 53.7%, OR 2.44, 95% CI 1.17–5.09, adjusted p = 0.02). Otherwise, the cohorts shared similar 24-month outcomes in terms of reaching the MCID for mJOA, NDI, NRS–arm pain, NRS–neck pain, and EQ-5D score (adjusted p > 0.05). There were no differences in the 3-month readmission (ACDF 4.1% vs PCF 3.9%, p = 0.97) and 24-month reoperation (ACDF 13.5% vs PCF 18.6%, p = 0.36) rates. CONCLUSIONS In a cohort limited to 3-level fusion surgical procedures, ACDF was associated with reduced blood loss, shorter hospitalization length, and higher routine home discharge rates; however, PCF resulted in lower rates of postoperative dysphagia. The procedures yielded comparably significant improvements in functional status (mJOA score), neck and arm pain, neck pain–related disability, and quality of life at 3, 12, and 24 months. ACDF patients had significantly higher odds of maximum satisfaction (NASS score 1). Given comparable outcomes, patients should be counseled on each approach’s complication profile to aid in surgical decision-making.
Cervical laminoplasty versus laminectomy and posterior cervical fusion for cervical myelopathy: propensity-matched analysis of 24-month outcomes from the Quality Outcomes Database
Mummaneni, Praveen V. , Chou, Dean , Bydon, Mohamad , Bisson, Erica F. , Shaffrey, Christopher I. , Gottfried, Oren N., Asher, Anthony L. , Coric, Domagoj , Potts, Eric A. , Foley, Kevin T. , Wang, Michael Y. , Fu, Kai-Ming, Virk, Michael S. , Knightly, John J. , Meyer, Scott A., Upadhyaya, Cheerag D., Shaffrey, Mark E., Buchholz, Avery L., Tumialán, Luis M. , Turner, Jay D. , Michalopoulos, Giorgos D. , Sherrod, Brandon A. , Haid, Regis W., Chan, Andrew K. , Michalopoulos, Giorgos , Yang, Eunice, Park, Paul , Agarwal, Nitin

Journal of Neurosurgery: Spine | August 12, 2023 | Volume: 39 | Issue: 5 | Pages: 671-681

10.3171/2023.6.spine23345 Get It

OBJECTIVE Compared with laminectomy with posterior cervical fusion (PCF), cervical laminoplasty (CL) may result in different outcomes for those operated on for cervical spondylotic myelopathy (CSM). The aim of this study was to compare 24-month patient-reported outcomes (PROs) for laminoplasty versus PCF by using the Quality Outcomes Database (QOD) CSM data set. METHODS This was a retrospective study using an augmented data set from the prospectively collected QOD Registry Cervical Module. Patients undergoing laminoplasty or PCF for CSM were included. Using the nearest-neighbor method, the authors performed 1:1 propensity matching based on age, operated levels, and baseline modified Japanese Orthopaedic Association (mJOA) and visual analog scale (VAS) neck pain scores. The 24-month PROs, i.e., mJOA, Neck Disability Index (NDI), VAS neck pain, VAS arm pain, EQ-5D, EQ-VAS, and North American Spine Society (NASS) satisfaction scores, were compared. Only cases in the subaxial cervical region were included; those that crossed the cervicothoracic junction were excluded. RESULTS From the 1141 patients included in the QOD CSM data set who underwent anterior or posterior surgery for cervical myelopathy, 946 (82.9%) had 24 months of follow-up. Of these, 43 patients who underwent laminoplasty and 191 who underwent PCF met the inclusion criteria. After matching, the groups were similar for baseline characteristics, including operative levels (CL group: 4.0 ± 0.9 vs PCF group: 4.2 ± 1.1, p = 0.337) and baseline PROs (p > 0.05), except for a higher percentage involved in activities outside the home in the CL group (95.3% vs 81.4%, p = 0.044). The 24-month follow-up for the matched cohorts was similar (CL group: 88.4% vs PCF group: 83.7%, p = 0.534). Patients undergoing laminoplasty had significantly lower estimated blood loss (99.3 ± 91.7 mL vs 186.7 ± 142.7 mL, p = 0.003), decreased length of stay (3.0 ± 1.6 days vs 4.5 ± 3.3 days, p = 0.012), and a higher rate of routine discharge (88.4% vs 62.8%, p = 0.006). The CL cohort also demonstrated a higher rate of return to activities (47.2% vs 21.2%, p = 0.023) after 3 months. Laminoplasty was associated with a larger improvement in 24-month NDI score (−19.6 ± 18.9 vs −9.1 ± 21.9, p = 0.031). Otherwise, there were no 3- or 24-month differences in mJOA, mean NDI, VAS neck pain, VAS arm pain, EQ-5D, EQ-VAS, and distribution of NASS satisfaction scores (p > 0.05) between the cohorts. CONCLUSIONS Compared with PCF, laminoplasty was associated with decreased blood loss, decreased length of hospitalization, and higher rates of home discharge. At 3 months, laminoplasty was associated with a higher rate of return to baseline activities. At 24 months, laminoplasty was associated with greater improvements in neck disability. Otherwise, laminoplasty and PCF shared similar outcomes for functional status, pain, quality of life, and satisfaction. Laminoplasty and PCF achieved similar neck pain scores, suggesting that moderate preoperative neck pain may not necessarily be a contraindication for laminoplasty.
Impact of preoperative spinal injections within 30 days of lumbar decompression on surgical outcomes: a matched institutional study
Michalopoulos, Giorgos D. , Chen, Selby , Kalani, Maziyar A. , Bydon, Mohamad , Flanigan, Patrick, Nathani, Karim R, Martini, Michael, Kalani, Maziyar, Michalopoulos, Giorgos , Flanigan, Patrick Michael , Nathani, Karim Rizwan , Martini, Michael L.

Journal of Neurosurgery: Spine | August 12, 2023 | Volume: 39 | Issue: 5 | Pages: 682-689

10.3171/2023.6.spine23356 Get It

OBJECTIVE The authors sought to determine how the temporal proximity of lumbar epidural spinal injection prior to surgery impacts clinical outcomes (e.g., 30-day readmission, postoperative complications, CSF leak) in patients undergoing lumbar decompression without fusion. METHODS The authors queried their institutional registry to identify patients who underwent elective lumbar decompression for spondylotic pathology between January 2019 and March 2022 at multiple centers within the same hospital network. Patients were divided into groups based on the time between their surgical date and the most recent preoperative spinal injection: group 1, patients with duration < 1 month; group 2, 1–3 months; and group 3, no spinal injection within 3 months. Primary outcomes of interest were the length of hospital stay, postoperative complications, rate of intraoperative CSF leak, and rates of reoperation and hospital readmission. For patients in groups 1 and 2, the authors also recorded the number of injections within 12 months prior to surgery to better understand the effect of multiple recent injections. The independent Student t-test and Pearson’s chi-square test were mainly performed for univariate analyses of the continuous and categorical variables, respectively. RESULTS A total of 121 and 283 patients received a spinal injection at < 1 month and 1–3 months prior to surgery, respectively, and were separately matched in a 3:1 ratio with 2562 patients with no history of preoperative spinal injection within 3 months before surgery. Among the matched cohorts, patients who received spinal injections < 1 month before lumbar decompression had significantly higher risks of 30-day complication (7.4% vs 0.8%, OR 9.6, p < 0.001), 30-day readmission (5.8% vs 2.2%, OR 3.5, p = 0.049), and 90-day readmission (9.1% vs 2.8%, OR 3.5, p = 0.003) than patients with no history of spinal injection. However, compared with patients with no history of spinal injection, the patients who received spinal injections 1–3 months before surgery were not at higher risk for postoperative complications or readmission. The CSF leak rates were significantly different between the three patient cohorts (10.7% vs 6.7% vs 4.9% for the < 1 month, 1–3 months, and no injection cohorts, respectively; p = 0.02). CONCLUSIONS Lumbar decompression within 1 month of preoperative spinal injection was associated with higher risks of readmission and postoperative complications, including CSF leak. However, with the exception of CSF leak, these risks were no longer observed when spinal injection occurred 1–3 months prior to lumbar decompression.
Traumatic vertebral artery injury: Denver grade, bilaterality, and stroke risk. A systematic review and meta-analysis
Michalopoulos, Giorgos D. , Pennington, Zach , Bambakidis, Peter, Alexander, A. Yohan , Lakomkin, Nikita , Graepel, Stephen , Meyer, Fredric B. , Bydon, Mohamad , Pennington, Zach , Michalopoulos, Giorgos , Alexander, A Yohan , Charalampous, Charalampos , Sammak, Sally El , Hassett, Leslie C.

Journal of Neurosurgery | July 29, 2023 | Volume: 140 | Issue: 2 | Pages: 522-536

10.3171/2023.5.jns222818 Get It

OBJECTIVE Vertebral artery injury (VAI), a complication of blunt trauma, may cause posterior circulation stroke. An association of disease severity, classified in Denver grades, with stroke risk has not been shown. Using a literature-based analysis, the authors estimated the incidence of VAI following blunt trauma with the aim to investigate the impact of Denver grade and bilateral VAI on stroke occurrence. METHODS A systematic review of the literature on VAI following blunt trauma was conducted, and data on its incidence, the severity per Denver grade, and stroke occurrence were collected. The incidence of VAI and stroke occurrence were analyzed cumulatively and between Denver grades. A meta-analysis with random-effects models was performed. RESULTS Fifty-six studies including 2563 patients were identified. The overall incidence of VAI was 0.49% among blunt trauma cases and 14.5% among patients screened via any type of angiography. The incidence rates of bilateral VAI and concurrent carotid injury among all VAIs were 12.3% and 19.2%, respectively. VAI severity by Denver grade was as follows: grade I, 23.4%; grade II, 28.2%; grade III, 5.8%; grade IV, 42.1%; and grade V, 0.5%. The overall stroke risk was 5.32%, differing significantly among lesions of different Denver grades (p = 0.02). Grade III and IV lesions had the highest stroke prevalence (9.8% and 10.9% respectively), while strokes occurred significantly less frequently in patients with grade I and II lesions (1.9% and 3.0%, respectively). Denver grade V cases were too rare for meaningful analysis. Bilateral VAI was associated with a 33.2% stroke prevalence. The association between Denver grade and stroke occurrence persisted in a sensitivity subanalysis including only unilateral cases (p = 0.03). CONCLUSIONS VAI complicates a small yet nontrivial fraction of blunt trauma cases, with Denver grade IV lesions being the most common. This is the first study to document a significantly higher stroke prevalence among grade III and IV VAIs compared with grade I and II VAIs independently from bilaterality. Bilateral VAIs carry a significantly higher stroke rate.
Developing nonlinear k-nearest neighbors classification algorithms to identify patients at high risk of increased length of hospital stay following spine surgery
Chan, Andrew K. , Bisson, Erica F. , Bydon, Mohamad , Glassman, Steven D. , Foley, Kevin T. , Shaffrey, Christopher I. , Potts, Eric A. , Shaffrey, Mark E., Coric, Domagoj , Knightly, John J. , Park, Paul , Wang, Michael Y. , Fu, Kai-Ming, Slotkin, Jonathan R., Asher, Anthony L. , Virk, Michael S. , Michalopoulos, Giorgos D. , Haid, Regis W., Chou, Dean , Mummaneni, Praveen V. , Michalopoulos, Giorgos , Shahrestani, Shane , Guan, Jian , Agarwal, Nitin

Neurosurgical Focus | June 1, 2023 | Volume: 54 | Issue: 6 | Pages: E7

10.3171/2023.3.focus22651 Get It

OBJECTIVE Spondylolisthesis is a common operative disease in the United States, but robust predictive models for patient outcomes remain limited. The development of models that accurately predict postoperative outcomes would be useful to help identify patients at risk of complicated postoperative courses and determine appropriate healthcare and resource utilization for patients. As such, the purpose of this study was to develop k-nearest neighbors (KNN) classification algorithms to identify patients at increased risk for extended hospital length of stay (LOS) following neurosurgical intervention for spondylolisthesis. METHODS The Quality Outcomes Database (QOD) spondylolisthesis data set was queried for patients receiving either decompression alone or decompression plus fusion for degenerative spondylolisthesis. Preoperative and perioperative variables were queried, and Mann-Whitney U-tests were performed to identify which variables would be included in the machine learning models. Two KNN models were implemented (k = 25) with a standard training set of 60%, validation set of 20%, and testing set of 20%, one with arthrodesis status (model 1) and the other without (model 2). Feature scaling was implemented during the preprocessing stage to standardize the independent features. RESULTS Of 608 enrolled patients, 544 met prespecified inclusion criteria. The mean age of all patients was 61.9 ± 12.1 years (± SD), and 309 (56.8%) patients were female. The model 1 KNN had an overall accuracy of 98.1%, sensitivity of 100%, specificity of 84.6%, positive predictive value (PPV) of 97.9%, and negative predictive value (NPV) of 100%. Additionally, a receiver operating characteristic (ROC) curve was plotted for model 1, showing an overall area under the curve (AUC) of 0.998. Model 2 had an overall accuracy of 99.1%, sensitivity of 100%, specificity of 92.3%, PPV of 99.0%, and NPV of 100%, with the same ROC AUC of 0.998. CONCLUSIONS Overall, these findings demonstrate that nonlinear KNN machine learning models have incredibly high predictive value for LOS. Important predictor variables include diabetes, osteoporosis, socioeconomic quartile, duration of surgery, estimated blood loss during surgery, patient educational status, American Society of Anesthesiologists grade, BMI, insurance status, smoking status, sex, and age. These models may be considered for external validation by spine surgeons to aid in patient selection and management, resource utilization, and preoperative surgical planning.