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Mualem, William

https://orcid.org/0000-0002-4036-8788

Mayo Clinic

Mayo Clinic

Citations 11

Comparing posterior cervical foraminotomy with anterior cervical discectomy and fusion in radiculopathic patients: an analysis from the Quality Outcomes Database
Mummaneni, Praveen V. , Bisson, Erica F. , Wang, Michael Y. , Chan, Andrew K. , Haid, Regis W., Knightly, John J. , Chou, Dean , 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 , Slotkin, Jonathan R., Potts, Eric A. , Fu, Kai-Ming, Asher, Anthony L. , Bydon, Mohamad , Mualem, William J, El Sammak, Sally, Michalopoulos, Giorgos D. , Mualem, William , Sammak, Sally El , Goldberg, Jacob L. , Agarwal, Nitin , Park, Paul

Journal of Neurosurgery: Spine | April 20, 2024 | Volume: 41 | Issue: 1 | Pages: 56-68

10.3171/2024.2.spine221280 Get It

OBJECTIVE The objective of this study was to compare clinical and patient-reported outcomes (PROs) between posterior foraminotomy and anterior cervical discectomy and fusion (ACDF) in patients presenting with cervical radiculopathy. METHODS The Quality Outcomes Database was queried for patients who had undergone ACDF or posterior foraminotomy for radiculopathy. To create two highly homogeneous groups, optimal individual matching was performed at a 5:1 ratio between the two groups on 29 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, underlying pathologies, and levels treated). Outcomes of interest were length of stay, reoperations, patient-reported satisfaction, increase in EQ-5D score, and decrease in Neck Disability Index (NDI) scores for arm and neck pain as long as 1 year after surgery. Noninferiority analysis of achieving patient satisfaction and minimal clinically important difference (MCID) in PROs was performed with an accepted risk difference of 5%. RESULTS A total of 7805 eligible patients were identified: 216 of these underwent posterior foraminotomy and were matched to 1080 patients who underwent ACDF. The patients who underwent ACDF had more underlying pathologies, lower EQ-5D scores, and higher NDI and neck pain scores at baseline. Posterior foraminotomy was associated with shorter hospitalization (0.5 vs 0.9 days, p < 0.001). Reoperations within 12 months were significantly more common among the posterior foraminotomy group (4.2% vs 1.9%, p = 0.04). The two groups performed similarly in PROs, with posterior foraminotomy being noninferior to ACDF in achieving MCID in EQ-5D and neck pain scores but also having lower rates of maximal satisfaction at 12 months (North American Spine Society score of 1 achieved by 65.2% posterior foraminotomy patients vs 74.6% of ACDF patients, p = 0.02). CONCLUSIONS The two procedures were found to be offered to different populations, with ACDF being selected for patients with more complicated pathologies and symptoms. After individual matching, posterior foraminotomy was associated with a higher reoperation risk within 1 year after surgery compared to ACDF (4.2% vs 1.9%). In terms of 12-month PROs, posterior foraminotomy was noninferior to ACDF in improving quality of life and neck pain. The two procedures also performed similarly in improving NDI scores and arm pain, but ACDF patients had higher maximal satisfaction rates.
Cerebral Revascularization: Bibliometric Analysis of Extracranial-intracranial/intracranial-intracranial Bypass Studies to Date
Durrani, Sulaman , Kreilach, Alec M, Krause, Victoria, Shoushtari, Ali, Nathani, Karim R, Bydon, Mohamad , Kreilach, Alec M., Krause, Victoria, Mualem, William

Journal of the American College of Surgeons | February 13, 2023 | Volume: 236 | Issue: 5 | Pages: S68-S68

10.1097/xcs.0000000000000625 Get It

Utilizing pre- and postoperative radiological parameters to predict surgical outcomes following untethering for tethered cord syndrome in a pediatric population
Durrani, Sulaman , Zamanian, Cameron , Michalopoulos, Giorgos D. , Rotter, Juliana , Bydon, Mohamad , Mualem, William , Michalopoulos, Giorgos , Nathani, Karim Rizwan , Ghaith, Abdul Karim , Daniels, David J.

Journal of Neurosurgery: Pediatrics | December 2, 2022 | Volume: 31 | Issue: 2 | Pages: 159-168

10.3171/2022.10.peds22459 Get It

OBJECTIVE Tethered cord syndrome (TCS) can lead to significant downstream neurological deficits including gait deterioration, incontinence, and often unexplained chronic low-back pain. Surgical intervention may relieve symptoms, but there are no defined radiological parameters associated with surgical outcomes and functional status. The authors aimed to define pre- and postoperative radiological parameters for assessing surgical outcomes in TCS. METHODS The authors performed a single-center retrospective review of all pediatric patients treated for TCS between 2016 and 2021. Patient baseline characteristics and operative metrics included age, sex, level of conus, level of procedure, tethering pathology, symptoms at presentation, complications, improvement of symptoms, and reoperation rate. MRI measurements included pre- and postoperative anterior canal distance (ACD) and bending angle (BA). RESULTS Thirty-three pediatric patients were identified who underwent untethering of the spinal cord and had pre- and postoperative MRI between 2016 and 2021. The mean patient age was 5.64 ± 5.33 years. Twenty patients (60.60%) were female. Regarding the site of untethering, 31 procedures (93.93%) were performed at the lumbosacral region and 2 (6.06%) were performed at the thoracolumbar region. The conus medullaris was found above L3 in 21.21% of patients. Postoperatively, 18.18% of patients experienced complications, 48.48% showed improvement in their symptoms, and 48.48% were equivocal or had persistent symptoms. The mean preoperative ACD0 (measured from the posterior vertebral body margin [middle] to the anterior margin of the conus medullaris) was 6.15 ± 3.18 mm, the postoperative ACD0 was 2.25 ± 2.72 mm, and the average change in ACD0 was −0.90 ± 1.31 mm. The mean preoperative BA was 26.00° ± 11.56°, the mean postoperative BA was 15.92° ± 9.81°, and the average change in BA was −10.08° ± 8.80°. An optimal cutoff value for preoperative BA to predict reoperation in pediatric patients with complex TCS undergoing surgery was ≥ 31.70° (area under the curve = 0.83). CONCLUSIONS In surgically treated patients with TCS, certain preoperative radiological parameters may be important in predicting postoperative surgical outcomes; these parameters can be evaluated and reported to indicate patients at high risk for complications. Further prospective multicenter research is warranted to offer robust evidence of association of patient outcomes with preoperative radiological parameters in TCS.
Assessing Complications of Occipitocervical Joint Fusion at Rural vs Urban Hospitals in the US
Nathani, Karim R, Durrani, Sulaman , Shoushtari, Ali, Jarrah, Ryan , Bydon, Mohamad , Mualem, William

Journal of the American College of Surgeons | October 14, 2022 | Volume: 235 | Issue: 5 | Pages: S161-S161

10.1097/01.xcs.0000894216.85649.9f Get It

Pediatric Epilepsy Surgery: Bibliometric Analysis to Date
Durrani, Sulaman , Shoushtari, Ali, Nathani, Karim R, Bydon, Mohamad , Mualem, William , Jarrah, Ryan

Journal of the American College of Surgeons | October 14, 2022 | Volume: 235 | Issue: 5 | Pages: S162-S162

10.1097/01.xcs.0000894228.38537.1f Get It

Comparison of surgical interventions for the treatment of early-onset scoliosis: a systematic review and meta-analysis
Kim, Gloria, Sammak, Sally El , Michalopoulos, Giorgos D. , Freedman, Brett A. , Bydon, Mohamad , Mualem, William , Michalopoulos, Giorgos , Pinter, Zachariah W.

Journal of Neurosurgery: Pediatrics | September 23, 2022 | Volume: 31 | Issue: 4 | Pages: 342-357

10.3171/2022.8.peds22156 Get It

OBJECTIVE Several growth-preserving surgical techniques are employed in the management of early-onset scoliosis (EOS). The authors’ objective was to compare the use of traditional growing rods (TGRs), magnetically controlled growing rods (MCGRs), Shilla growth guidance techniques, and vertically expanding prosthetic titanium ribs (VEPTRs) for the management of EOS. METHODS A systematic review of electronic databases, including Ovid MEDLINE and Cochrane, was performed. Outcomes of interest included correction of Cobb angle, T1–S1 distance, and complication rate, including alignment, hardware failure and infection, and planned and unplanned reoperation rates. The percent changes and 95% CIs were pooled across studies using random-effects meta-analysis. RESULTS A total of 67 studies were identified, which included 2021 patients. Of these, 1169 (57.8%) patients underwent operations with TGR, 178 (8.8%) Shilla growth guidance system, 448 (22.2%) MCGR, and 226 (11.1%) VEPTR system. The mean ± SD age of the cohort was 6.9 ± 1.2 years. The authors found that the Shilla technique provided the most significant improvement in coronal Cobb angle immediately after surgery (mean [95% CI] 64.3% [61.4%–67.2%]), whereas VEPTR (27.6% [22.7%–33.6%]) performed significantly worse. VEPTR also performed significantly worse than the other techniques at final follow-up. The techniques also provided comparable gains in T1–S1 height immediately postoperatively (mean [95% CI] 10.7% [8.4%–13.0%]); however, TGR performed better at final follow-up (21.4% [18.7%–24.1%]). Complications were not significantly different among the patients who underwent the Shilla, TGR, MCGR, and VEPTR techniques, except for the rate of infections. The TGR technique had the lowest rate of unplanned reoperations (mean [95% CI] 15% [10%–23%] vs 24% [19%–29%]) but the highest number of planned reoperations per patient (5.31 [4.83–5.82]). The overall certainty was also low, with a high risk of bias across studies. CONCLUSIONS This analysis suggested that the Shilla technique was associated with a greater early coronal Cobb angle correction, whereas use of VEPTR was associated with a lower correction rate at any time point. TGR offered the most significant height gain at final follow-up. The complication rates were comparable across all surgical techniques. The optimal surgical approach should be tailored to individual patients, taking into consideration the strengths and limitations of each option.
Predictors of favorable outcome following hypoglossal-to-facial nerve anastomosis for facial nerve palsy: a systematic review and patient-level analysis of a literature-based cohort
Alexander, A. Yohan , Bambakidis, Peter, Michalopoulos, Giorgos D. , Kerezoudis, Panagiotis , Link, Michael J. , Peris‐Celda, Maria , Bydon, Mohamad , Mualem, William , Michalopoulos, Giorgos , Alexander, A Yohan , Mardini, Samir

Journal of Neurosurgery | September 9, 2022 | Volume: 138 | Issue: 4 | Pages: 1034-1042

10.3171/2022.6.jns22240 Get It

OBJECTIVE Facial nerve palsy is a debilitating condition that can arise from iatrogenic, traumatic, or congenital causes. One treatment to improve function of the facial muscles after facial nerve injury is hypoglossal-to-facial nerve anastomosis (HFA). HFA’s efficacy and predictors of its success vary in the literature. Here, the authors present a patient-level analysis of a literature-based cohort to assess outcomes and investigate predictors of success for HFA. METHODS Seven electronic databases were queried for studies providing baseline characteristics and outcomes of patients who underwent HFA. Postoperative outcomes were measured using the House-Brackmann (HB) grading scale. A change in HB grade of 3 points or more was classified as favorable. A cutoff value for time to anastomosis associated with a favorable outcome was determined using the Youden Index. RESULTS Nineteen articles with 157 patients met the inclusion criteria. The mean follow-up length was 27.4 months, and the mean time to anastomosis after initial injury was 16 months. The end-to-side and end-to-end anastomosis techniques were performed on 84 and 48 patients, respectively. Of the 130 patients who had available preoperative and postoperative HB data, 60 (46.2%) had a favorable outcome. Time from initial injury to anastomosis was significantly different between patients with favorable and unfavorable outcomes (7.3 months vs 29.2 months, respectively; p < 0.001). The optimal cutoff for time to anastomosis to achieve a favorable outcome was 6.5 months (area under the curve 0.75). Patients who underwent anastomosis within 6.5 months of injury were more likely to achieve a favorable outcome (73% vs 31%, p < 0.001). CONCLUSIONS HFA is an effective method for restoring facial nerve function. Favorable outcomes for facial nerve palsy may be more likely to occur when time to anastomosis is within a 6.5-month window.
Commentary: Validation of Machine Learning-Based Automated Surgical Instrument Annotation Using Publicly Available Intraoperative Video
Bydon, Mohamad , Durrani, Sulaman , Mualem, William

Operative Neurosurgery | August 16, 2022 | Volume: 23 | Issue: 3 | Pages: e158-e159

10.1227/ons.0000000000000285 Get It

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.
Commentary: Machine Learning to Predict Successful Opioid Dose Reduction or Stabilization After Spinal Cord Stimulation
Bydon, Mohamad , Durrani, Sulaman , Mualem, William

Neurosurgery | May 5, 2022 | Volume: 91 | Issue: 2 | Pages: e41-e42

10.1227/neu.0000000000001989 Get It