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Yolcu, Yagiz Ugur

Mayo Clinic

Mayo Clinic

Citations 8

Survival and associated predictors for patients with pineoblastoma or pineal parenchymal tumors of intermediate differentiation older than 3 years: Insights from the National Cancer Database
Kerezoudis, Panagiotis , Yolcu, Yagiz U. , Laack, Nadia N., Ruff, Michael W. , Khatua, Soumen , Kizilbash, Sani H. , Yolcu, Yagiz Ugur, Kizilbash, Sani H , Daniels, David J. , Burns, Terry C.

Neuro-Oncology Advances | April 17, 2022 | Volume: 4 | Issue: 1 | Pages: No page available

10.1093/noajnl/vdac057 Get It

Abstract Background The management of pineal parenchymal tumors remains controversial. Methods The 2004-2017 National Cancer Database was queried for cases (age >3 years) with histologically confirmed pineal parenchymal tumors of intermediate differentiation (PPTID, n = 90) or pineoblastoma (n = 106). Results Within the PPTID group, median age was 41 years; 49% were males. Five- and 10-year survival were 83% and 78%, respectively. Adjuvant radiation and chemotherapy were administered in 64% and 17% patients, respectively. The effect of radiation with or without chemotherapy (HR 1.15, P = .81, and HR 1.31, P = .72, respectively), and extent of resection (HR = 1.07, P = .93) was not significant. Within the pineoblastoma group, median age was 25 years; 51% were males. Five- and 10-year survival were 66% and 42%, respectively. Adjuvant radiation and chemotherapy were administered in 72% and 51%, respectively. In multivariable analysis, patients with pineoblastoma who received both radiation and chemotherapy (n = 39) had significantly lower hazard of death (HR 0.35, 95% CI 0.14-0.85, P = .02) compared to those who received radiation alone (n = 20) or no adjuvant treatment (n = 19). Finally, females in the pineoblastoma group were found to have a lower hazard of death compared to males (HR 0.24, 95% CI 0.10-0.58, P = .001); this comparison trended toward statistical significance in the PPTID subgroup (HR 0.40, 95% CI 0.14-1.08, P = .07). Conclusions Survival rates were higher in patients with PPTID vs patients with pineoblastoma. Adjuvant chemoradiation was associated with improved survival in pineoblastoma and females had lower hazards of death. Further research should identify specific patient profiles and molecular subgroups more likely to benefit from multimodality therapy.
Hybrid surgery: a comparison of early postoperative outcomes between anterior cervical discectomy and fusion and cervical disc arthroplasty
Michalopoulos, Giorgos D. , Bhandarkar, Archis R. , Jarrah, Ryan , Yolcu, Yagiz U. , Alvi, Mohammed Ali , Sebastian, Arjun S. , Freedman, Brett A. , Bydon, Mohamad , Yolcu, Yagiz Ugur, Alvi, Mohammed Ali , Michalopoulos, Giorgos , Ghaith, Abdul Karim

Journal of Neurosurgery: Spine | November 26, 2021 | Volume: 36 | Issue: 4 | Pages: 575-584

10.3171/2021.7.spine21478 Get It

OBJECTIVE Hybrid surgery (HS) is the combination of anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at different levels in the same operation. The aim of this study was to investigate perioperative variables, 30-day postoperative outcomes, and complications of HS in comparison with those of CDA and ACDF. METHODS The authors queried the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) registry for patients who underwent multilevel primary HS, CDA, and ACDF for degenerative disc disease from 2015 to 2019. The authors compared these three operations in terms of 30-day postoperative outcomes, specifically readmission and reoperation rates, discharge destination, and complications. RESULTS This analysis included 439 patients who underwent HS, 976 patients who underwent CDA, and 27,460 patients who underwent ACDF. Patients in the HS and CDA groups were younger, had fewer comorbidities, and myelopathy was less often the indication for surgery compared with patients who underwent ACDF. For the HS group, the unplanned readmission rate was 0.7%, index surgery–related reoperation rate was 0.3%, and nonroutine discharge rate was 2.1%. Major and minor complications were also rare, with rates of 0.2% for each. The mean length of stay in the HS group was 1.5 days. The association of HS with better outcomes in univariate analysis was not evident after adjustment for confounding factors. CONCLUSIONS The authors found that HS was noninferior to ACDF and CDA in terms of early postoperative outcomes among patients treated for degenerative disc disease.
Time-to-enrollment in clinical trials investigating neurological recovery in chronic spinal cord injury: observations from a systematic review and ClinicalTrials.gov database
Moinuddin, F. M. , Yolcu, Yagiz Ugur, Wahood, Waseem , Zreik, Jad, Goncalves, Sandy, Windebank, Anthony John, Qu, Wenchun , Bydon, Mohamad , Yolcu, Yagiz Ugur, Windebank, Anthony John

Neural Regeneration Research | September 19, 2021 | Volume: 17 | Issue: 5 | Pages: 953-958

10.4103/1673-5374.324826 Get It

Currently, large numbers of clinical trials are performed to investigate different forms of experimental therapy for patients suffering from chronic spinal cord injury (SCI). However, for the enrollment process, there are different views on how the time period between injury and interventions should be determined. Herein, we sought to evaluate the impact of time-to-enrollment in chronic SCI clinical trials. A data set comprising 957 clinical studies from clinicalTrials.gov was downloaded and analyzed focusing on the eligibility criteria for post-injury time-to-enrollment. We also aggregated individual patient data from nine clinical trials of regenerative interventions for chronic SCI selected by a systematic literature search from 1990 to 2018. Characteristics of the studies were assessed and compared by dividing into three groups based on time-to-enrollment (group 1 ≤ 12 months, group 2 = 12–23 months and group 3 ≥ 24 months). In ClinicalTrials.gov registry, 445 trials were identified for chronic SCI where 87% (385) were unrestricted in the maximum post-injury time for trial eligibility. From systematic literature search, nine studies and 156 patients (group 1 = 30, group 2 = 55 and group 3 = 71) were included. The range of time-to-enrollment was 0.5 to 321 months in those studies. We also observed various degrees of motor and sensory improvement in between three time-to-enrollment groups. Our results indicate that enrolling wide ranges of time-to-enrollment in a group may present imprecise outcomes. Clinical trial designs should consider appropriate post-injury time frames to evaluate therapeutic benefit.
Diagnostic yield, accuracy, and complication rate of CT-guided biopsy for spinal lesions: a systematic review and meta-analysis
Michalopoulos, Giorgos D. , Yolcu, Yagiz U. , Alvi, Mohammed Ali , Bydon, Mohamad , Yolcu, Yagiz Ugur, Bydon, Mohamad , Alvi, Mohammed Ali , Michalopoulos, Giorgos , Ghaith, Abdul Karim , Carr, Carrie M.

Journal of NeuroInterventional Surgery | April 21, 2021 | Volume: 13 | Issue: 9 | Pages: 841-847

10.1136/neurintsurg-2021-017419 Get It

Background CT-guided biopsy is a commonly used diagnostic procedure for spinal lesions. This meta-analysis aims to investigate its diagnostic performance and complications, as well as factors influencing outcomes. Methods A systematic review of the literature was performed to identify studies reporting outcomes of CT-guided biopsies for spinal lesions. Diagnostic yield (ie, the rate of procedures resulting in a specific pathological diagnosis) and diagnostic accuracy (ie, the rate of procedures resulting in the correct diagnosis) were the primary outcomes of interest. Complications following biopsy procedures were also included. Results Thirty-nine studies with 3917 patients undergoing 4181 procedures were included. Diagnostic yield per procedure was 91% (95% CI 88% to 94%) among 3598 procedures. The most common reason for non-diagnostic biopsies was inadequacy of sample. No difference in diagnostic yield between different locations and between lytic, sclerotic, and mixed lesions was found. Diagnostic yield did not differ between procedures using ≤13G and ≥14G needles. Diagnostic accuracy per procedure was 86% (95% CI 82% to 89%) among 3054 procedures. Diagnostic accuracy among 2426 procedures that yielded a diagnosis was 94% (95% CI 92% to 96%). Complication rate was 1% (95% CI 0.4% to 1.9%) among 3357 procedures. Transient pain and minor hematoma were the most common complications encountered. Conclusion In our meta-analysis of 39 studies reporting diagnostic performance and complications of CT-guided biopsy, we found a diagnostic yield of 91% and diagnostic accuracy of 86% with a complication rate of 1%. Diagnostic yield did not differ between different locations, between lytic, sclerotic and mixed lesions, and between wide- and thin-bore needles.
Nervous system involvement in SARS-coronavirus infection: a review on lessons learned from the previous outbreaks, ongoing pandemic and what to expect in the future
Bhatti, Atiq ur Rehman , Zreik, Jad, Yolcu, Yagiz U. , Alvi, Mohammed Ali , Quiñones‐Hinojosa, Alfredo , Bydon, Mohamad , Yolcu, Yagiz Ugur, Alvi, Mohammed Ali , Abode-Iyamah, Kingsley

International Journal of Neuroscience | November 19, 2020 | Volume: 132 | Issue: 9 | Pages: 930-938

10.1080/00207454.2020.1853724 Get It

Institutional databases may underestimate the risk factors for 30-day unplanned readmissions compared to national databases
Kurian, Shyam J. , Yolcu, Yagiz U. , Zreik, Jad, Alvi, Mohammed Ali , Freedman, Brett A. , Bydon, Mohamad , Yolcu, Yagiz Ugur, Alvi, Mohammed Ali

Journal of Neurosurgery: Spine | July 31, 2020 | Volume: 33 | Issue: 6 | Pages: 845-853

10.3171/2020.5.spine20395 Get It

OBJECTIVEThe National Surgical Quality Improvement Program (NSQIP) and National Readmissions Database (NRD) are two widely used databases for research studies. However, they may not provide generalizable information in regard to individual institutions. Therefore, the objective of the present study was to evaluate 30-day readmissions following anterior cervical discectomy and fusion (ACDF) and posterior lumbar fusion (PLF) procedures by using these two national databases and an institutional cohort.METHODSThe NSQIP and NRD were queried for patients undergoing elective ACDF and PLF, with the addition of an institutional cohort. The outcome of interest was 30-day readmissions following ACDF and PLF, which were unplanned and related to the index procedure. Subsequently, univariable and multivariable analyses were conducted to determine the predictors of 30-day readmissions by using both databases and the institutional cohort.RESULTSAmong all identified risk factors, only hypertension was found to be a common risk factor between NRD and the institutional cohort following ACDF. NSQIP and the institutional cohort both showed length of hospital stay to be a significant predictor for 30-day related readmission following PLF. There were no overlapping variables among all 3 cohorts for either ACDF or PLF. Additionally, the national databases identified a greater number of risk factors for 30-day related readmissions than did the institutional cohort for both procedures.CONCLUSIONSOverall, significant differences were seen among all 3 cohorts with regard to top predictors of 30-day unplanned readmissions following ACDF and PLF. The higher quantity of significant predictors found in the national databases may suggest that looking at single-institution series for such analyses may result in underestimation of important variables affecting patient outcomes, and that big data may be helpful in addressing this concern.
The impact of platelet-rich plasma on postoperative outcomes after spinal fusion: a systematic review and meta-analysis
Yolcu, Yagiz U. , Wahood, Waseem , Eissa, Abdullah T. , Alvi, Mohammed Ali , Freedman, Brett A. , Elder, Benjamin D. , Bydon, Mohamad , Yolcu, Yagiz Ugur, Alvi, Mohammed Ali

Journal of Neurosurgery: Spine | May 22, 2020 | Volume: 33 | Issue: 4 | Pages: 540-547

10.3171/2020.3.spine2046 Get It

OBJECTIVEPlatelet-rich plasma (PRP) is a biological agent obtained by centrifuging a sample of blood and retrieving a high concentration of platelets and plasma components. The concentrate is then stimulated for platelet secretion of various growth factors and cytokines. Although it is not widely used in clinical practice, its role in augmenting bony union among patients undergoing spinal fusion has been assessed in several clinical studies. The objective of this study was to perform a systematic review and meta-analysis of the existing literature to determine the efficacy of PRP use in spinal fusion procedures.METHODSA comprehensive literature search was conducted using PubMed, Scopus, and EMBASE for studies from all available dates. From eligible studies, data regarding the fusion rate and method of assessing fusion, estimated blood loss (EBL), and baseline and final visual analog scale (VAS) scores were collected as the primary outcomes of interest. Patients were grouped by those undergoing spinal fusion with PRP and bone graft (PRP group) and those only with bone graft (graft-only group).RESULTSThe literature search resulted in 207 articles. Forty-five full-text articles were screened, of which 11 studies were included, resulting in a meta-analysis including 741 patients. Patients without PRP were more likely to have a successful fusion at the last follow-up compared with those with PRP in their bone grafts (OR 0.53, 95% CI 0.34–0.84; p = 0.006). There was no statistically significant difference with regard to change in VAS scores (OR 0.00, 95% CI −2.84 to 2.84; p > 0.99) or change in EBL (OR 3.67, 95% CI −67.13–74.48; p = 0.92) between the groups.CONCLUSIONSThis study found that the additional use of PRP was not associated with any significant improvement in patient-reported outcomes and was actually found to be associated with lower fusion rates compared with standard grafting techniques. Thus, PRP may have a limited role in augmenting spinal fusion.
Hospital volume-outcome relationship in severe traumatic brain injury: stratified analysis by level of trauma center
Tsai, Sung Huang Laurent , Alvi, Mohammed Ali , Kerezoudis, Panagiotis , Yolcu, Yagiz U. , Wahood, Waseem , Habermann, Elizabeth B. , Bydon, Mohamad , Yolcu, Yagiz Ugur, Habermann, Elizabeth , Alvi, Mohammed Ali , Goyal, Anshit , Burns, Terry C.

Journal of Neurosurgery | March 20, 2020 | Volume: 134 | Issue: 4 | Pages: 1303-1315

10.3171/2020.1.jns192115 Get It

OBJECTIVE The nature of the volume-outcome relationship in cases with severe traumatic brain injury (TBI) remains unclear, with considerable interhospital variation in patient outcomes. The objective of this study was to understand the state of the volume-outcome relationship at different levels of trauma centers in the United States. METHODS The authors queried the National Trauma Data Bank for the years 2007–2014 for patients with severe TBI. Case volumes for each level of trauma center organized into quintiles (Q1–Q5) served as the primary predictor. Analyzed outcomes included in-hospital mortality, total hospital length of stay (LOS), and intensive care unit (ICU) stay. Multivariable regression models were performed for in-hospital mortality, overall complications, and total hospital and ICU LOSs to adjust for possible confounders. The analysis was stratified by level designation of the trauma center. Statistical significance was established at p < 0.001 to avoid a type I error due to a large sample size. RESULTS A total of 122,445 patients were included. Adjusted analysis did not demonstrate a significant relationship between increasing hospital volume of severe TBI cases and in-hospital mortality, complications, and nonhome hospital discharge disposition among level I–IV trauma centers. However, among level II trauma centers, hospital LOS was longer for the highest volume quintile (adjusted mean difference [MD] for Q5: 2.83 days, 95% CI 1.40–4.26 days, p < 0.001, reference = Q1). For level III and IV trauma centers, both hospital LOS and ICU LOS were longer for the highest volume quintile (adjusted MD for Q5: LOS 4.6 days, 95% CI 2.3–7.0 days, p < 0.001; ICU LOS 3.2 days, 95% CI 1.6–4.8 days, p < 0.001). CONCLUSIONS Higher volumes of severe TBI cases at a lower level of trauma center may be associated with a longer LOS. These results may assist policymakers with target interventions for resource allocation and point to the need for careful prehospital decision-making in patients with severe TBI.