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Paul S. Page, Garret P. Greeneway, Simon G. Ammanuel, and Daniel K. Resnick

OBJECTIVE

Lumbar synovial cysts (LSCs) represent a relatively rare clinical pathology that may result in radiculopathy or neurogenic claudication. Because of the potential for recurrence of these cysts, some authors advocate for segmental fusion, as opposed to decompression alone, as a way to eliminate the risk for recurrence. The objective of this study was to create a predictive score for synovial cyst recurrence following decompression without fusion.

METHODS

A retrospective chart review was completed of all patients evaluated at a single center over 20 years who were found to have symptomatic LSCs requiring intervention. Only patients undergoing decompression without fusion were included in the analysis. Following this review, baseline characteristics were obtained as well as radiological information. A machine learning method (risk-calibrated supersparse linear integer model) was then used to create a risk stratification score to identify patients at high risk for symptomatic cyst recurrence requiring repeat surgical intervention. Following the creation of this model, a fivefold cross-validation was completed.

RESULTS

In total, 89 patients were identified who had complete radiological information. Of these 89 patients, 11 developed cyst recurrence requiring reoperation. The Lumbar Synovial Cyst Score was then created with an area under the curve of 0.83 and calibration error of 11.0%. Factors predictive of recurrence were found to include facet inclination angle > 45°, canal stenosis > 50%, T2 joint space hyperintensity, and presence of grade I spondylolisthesis. The probability of cyst recurrence ranged from < 5% for a score of 2 or less to > 88% for a score of 7.

CONCLUSIONS

The Lumbar Synovial Cyst Score model is a quick and accurate tool to assist in clinical decision-making in the treatment of LSCs.

Free access

nlm-article

Simon G. Ammanuel, Nyle C. Almeida, Garret Kurteff, Sofia Kakaizada, Annette M. Molinaro, Mitchel S. Berger, Edward F. Chang, and Shawn L. Hervey-Jumper

OBJECTIVE

Impairments of speech are common in patients with glioma and negatively impact health-related quality of life (HRQoL). The benchmark for clinical assessments is task-based measures, which are not always feasible to administer and may miss essential components of HRQoL. In this study, the authors tested the hypothesis that variations in natural language (NL) correlate with HRQoL in a pattern distinct from task-based measures of language performance.

METHODS

NL use was assessed using audio samples collected unobtrusively from 18 patients with newly diagnosed low- and high-grade glioma. NL measures were calculated using manual segmentation and correlated with Quality of Life in Neurological Disorders (Neuro-QoL) outcomes. Spearman’s rank-order correlation was used to determine relationships between Neuro-QoL scores and NL measures.

RESULTS

The distribution of NL measures across the entire patient cohort included a mean ± SD total time speaking of 11.5 ± 2.20 seconds, total number of words of 27.2 ± 4.44, number of function words of 10.9 ± 1.68, number of content words of 16.3 ± 2.91, and speech rate of 2.61 ± 0.20 words/second. Speech rate was negatively correlated with functional domains (rho = −0.62 and p = 0.007 for satisfaction with social roles; rho = −0.74 and p < 0.001 for participation in social roles) but positively correlated with impairment domains (rho = 0.58 and p = 0.009 for fatigue) of Neuro-QoL.

CONCLUSIONS

Assessment of NL at the time of diagnosis may be a useful measure in the context of treatment planning and monitoring outcomes for adult patients with glioma.

Free access

nlm-article

Simon G. Ammanuel, Nyle C. Almeida, Garret Kurteff, Sofia Kakaizada, Annette M. Molinaro, Mitchel S. Berger, Edward F. Chang, and Shawn L. Hervey-Jumper

OBJECTIVE

Impairments of speech are common in patients with glioma and negatively impact health-related quality of life (HRQoL). The benchmark for clinical assessments is task-based measures, which are not always feasible to administer and may miss essential components of HRQoL. In this study, the authors tested the hypothesis that variations in natural language (NL) correlate with HRQoL in a pattern distinct from task-based measures of language performance.

METHODS

NL use was assessed using audio samples collected unobtrusively from 18 patients with newly diagnosed low- and high-grade glioma. NL measures were calculated using manual segmentation and correlated with Quality of Life in Neurological Disorders (Neuro-QoL) outcomes. Spearman’s rank-order correlation was used to determine relationships between Neuro-QoL scores and NL measures.

RESULTS

The distribution of NL measures across the entire patient cohort included a mean ± SD total time speaking of 11.5 ± 2.20 seconds, total number of words of 27.2 ± 4.44, number of function words of 10.9 ± 1.68, number of content words of 16.3 ± 2.91, and speech rate of 2.61 ± 0.20 words/second. Speech rate was negatively correlated with functional domains (rho = −0.62 and p = 0.007 for satisfaction with social roles; rho = −0.74 and p < 0.001 for participation in social roles) but positively correlated with impairment domains (rho = 0.58 and p = 0.009 for fatigue) of Neuro-QoL.

CONCLUSIONS

Assessment of NL at the time of diagnosis may be a useful measure in the context of treatment planning and monitoring outcomes for adult patients with glioma.

Open access

nlm-article

Bo Li, Gregory A. Kuzmik, Saman Shabani, Nitin Agarwal, Alysha Jamieson, Thomas Wozny, Simon Ammanuel, Praveen V. Mummaneni, and Dean Chou

It can be difficult to avoid violating the pleura during the retropleural approach to the thoracolumbar spine. In this video, the authors resect a short segment of rib to allow more room for pleural dissection during a minimally invasive (MIS) lateral retropleural approach. After a lateral MIS skin incision, the rib is dissected and removed, clearly identifying the retropleural space. The curvature of the rib can then be followed, decreasing the risk of pleural violation. The pleura can then be mobilized ventrally until the spine is accessed. Managing the diaphragm is also illustrated by separating the fibers without a traditional cut through the muscle.

The video can be found here: https://stream.cadmore.media/r10.3171/2022.3.FOCVID21138

Open access

nlm-article

Ayman W. Taher, Paul S. Page, Garret P. Greeneway, Simon Ammanuel, Katherine M. Bunch, Lars Meisner, Amgad Hanna, and Darnell Josiah

BACKGROUND

Fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH) are considered highly unstable injuries with high risk for neurological injury. Surgical intervention is the standard of care for these patients to avoid secondary spinal cord injuries. Despite this, certain cases may necessitate a nonoperative approach. Herein within, the authors describe three cases of cervical, thoracic, and lumbar fractures in the setting of DISH that were successfully treated via orthosis.

OBSERVATIONS

The authors present three cases of fractures in patients with DISH. A 74-year-old female diagnosed with an acute fracture of a flowing anterior osteophyte at C6–C7 treated with a cervical orthosis. A 78-year-old male with an anterior fracture of the ankylosed T7–T8 vertebrae managed with a Jewett hyperextension brace. Finally, a 57-year-old male with an L1–L2 disc space fracture treated with a thoraco-lumbo-sacral orthosis. All patients recovered successfully.

LESSONS

In certain cases, conservative treatment may be more appropriate for fractures in the setting of DISH as an alternative to the surgical standard of care. Most fractures in the setting of DISH are unstable, therefore it is necessary to manage these patients on a case-by-case basis.

Restricted access

nlm-article

Lei Zhao, Liwei Peng, Peng Wang, and Weixin Li

Free access

nlm-article

Hansen Deng, Andrew K. Chan, Simon G. Ammanuel, Alvin Y. Chan, Taemin Oh, Henry C. Skrehot, Caleb S. Edwards, Sravani Kondapavulur, Amy D. Nichols, Catherine Liu, John K. Yue, Sanjay S. Dhall, Aaron J. Clark, Dean Chou, Christopher P. Ames, and Praveen V. Mummaneni

OBJECTIVE

Surgical site infection (SSI) following spine surgery causes major morbidity and greatly impedes functional recovery. In the modern era of advanced operative techniques and improved perioperative care, SSI remains a problematic complication that may be reduced with institutional practices. The objectives of this study were to 1) characterize the SSI rate and microbial etiology following spine surgery for various thoracolumbar diseases, and 2) identify risk factors that were associated with SSI despite current perioperative management.

METHODS

All patients treated with thoracic or lumbar spine operations on the neurosurgery service at the University of California, San Francisco from April 2012 to April 2016 were formally reviewed for SSI using the National Healthcare Safety Network (NHSN) guidelines. Preoperative risk variables included age, sex, BMI, smoking, diabetes mellitus (DM), coronary artery disease (CAD), ambulatory status, history of malignancy, use of preoperative chlorhexidine gluconate (CHG) showers, and the American Society of Anesthesiologists (ASA) classification. Operative variables included surgical pathology, resident involvement, spine level and surgical technique, instrumentation, antibiotic and steroid use, estimated blood loss (EBL), and operative time. Multivariable logistic regression was used to evaluate predictors for SSI. Odds ratios and 95% confidence intervals were reported.

RESULTS

In total, 2252 consecutive patients underwent thoracolumbar spine surgery. The mean patient age was 58.6 ± 13.8 years and 49.6% were male. The mean hospital length of stay was 6.6 ± 7.4 days. Sixty percent of patients had degenerative conditions, and 51.9% underwent fusions. Sixty percent of patients utilized presurgery CHG showers. The mean operative duration was 3.7 ± 2 hours, and the mean EBL was 467 ± 829 ml. Compared to nonfusion patients, fusion patients were older (mean 60.1 ± 12.7 vs 57.1 ± 14.7 years, p < 0.001), were more likely to have an ASA classification > II (48.0% vs 36.0%, p < 0.001), and experienced longer operative times (252.3 ± 120.9 minutes vs 191.1 ± 110.2 minutes, p < 0.001). Eleven patients had deep SSI (0.49%), and the most common causative organisms were methicillin-sensitive Staphylococcus aureus and methicillin-resistant S. aureus. Patients with CAD (p = 0.003) or DM (p = 0.050), and those who were male (p = 0.006), were predictors of increased odds of SSI, and presurgery CHG showers (p = 0.001) were associated with decreased odds of SSI.

CONCLUSIONS

This institutional experience over a 4-year period revealed that the overall rate of SSI by the NHSN criteria was low at 0.49% following thoracolumbar surgery. This was attributable to the implementation of presurgery optimization, and intraoperative and postoperative measures to prevent SSI across the authors’ institution. Despite prevention measures, having a history of CAD or DM, and being male, were risk factors associated with increased SSI, and presurgery CHG shower utilization decreased SSI risk in patients.

Free access

nlm-article

Joseph H. Garcia, Ethan A. Winkler, Ramin A. Morshed, Alex Lu, Simon G. Ammanuel, Satvir Saggi, Elaina J. Wang, Steve Braunstein, Christine K. Fox, Heather J. Fullerton, Helen Kim, Daniel L. Cooke, Steven W. Hetts, Michael T. Lawton, Adib A. Abla, and Nalin Gupta

OBJECTIVE

Children with cerebral arteriovenous malformations (AVMs) can present with seizures, potentially increasing morbidity and impacting clinical management. However, the factors that lead to seizures as a presenting sign are not well defined. While AVM-related seizures have been described in case series, most studies have focused on adults and have included patients who developed seizures after an AVM rupture. To address this, the authors sought to analyze demographic and morphological characteristics of AVMs in a large cohort of children.

METHODS

The demographic, clinical, and AVM morphological characteristics of 189 pediatric patients from a single-center database were studied. Univariate and multivariate logistic regression models were used to test the effect of these characteristics on seizures as an initial presenting symptom in patients with unruptured brain AVMs.

RESULTS

Overall, 28 of 189 patients initially presented with seizures (14.8%). By univariate comparison, frontal lobe location (p = 0.02), larger AVM size (p = 0.003), older patient age (p = 0.04), and the Supplemented Spetzler-Martin (Supp-SM) grade (0.0006) were associated with seizure presentation. Multivariate analysis confirmed an independent effect of frontal lobe AVM location and higher Supp-SM grade. All patients presenting with seizures had AVMs in the cortex or subcortical white matter.

CONCLUSIONS

While children and adults share some risk factors for seizure presentation, their risk factor profiles do not entirely overlap. Pediatric patients with cortical AVMs in the frontal lobe were more likely to present with seizures. Additionally, the Supp-SM grade was highly associated with seizure presentation. Future clinical research should focus on the effect of therapeutic interventions targeting AVMs on seizure control in these patients.

Restricted access

nlm-article

Lei Zhao, Liwei Peng, Peng Wang, and Weixin Li

Restricted access

nlm-article

Satvir Saggi, Ethan A. Winkler, Simon G. Ammanuel, Ramin A. Morshed, Joseph H. Garcia, Jacob S. Young, Alexa Semonche, Heather J. Fullerton, Helen Kim, Daniel L. Cooke, Steven W. Hetts, Adib Abla, Michael T. Lawton, and Nalin Gupta

OBJECTIVE

Ruptured brain arteriovenous malformations (bAVMs) in a child are associated with substantial morbidity and mortality. Prior studies investigating predictors of hemorrhagic presentation of a bAVM during childhood are limited. Machine learning (ML), which has high predictive accuracy when applied to large data sets, can be a useful adjunct for predicting hemorrhagic presentation. The goal of this study was to use ML in conjunction with a traditional regression approach to identify predictors of hemorrhagic presentation in pediatric patients based on a retrospective cohort study design.

METHODS

Using data obtained from 186 pediatric patients over a 19-year study period, the authors implemented three ML algorithms (random forest models, gradient boosted decision trees, and AdaBoost) to identify features that were most important for predicting hemorrhagic presentation. Additionally, logistic regression analysis was used to ascertain significant predictors of hemorrhagic presentation as a comparison.

RESULTS

All three ML models were consistent in identifying bAVM size and patient age at presentation as the two most important factors for predicting hemorrhagic presentation. Age at presentation was not identified as a significant predictor of hemorrhagic presentation in multivariable logistic regression. Gradient boosted decision trees/AdaBoost and random forest models identified bAVM location and a concurrent arterial aneurysm as the third most important factors, respectively. Finally, logistic regression identified a left-sided bAVM, small bAVM size, and the presence of a concurrent arterial aneurysm as significant risk factors for hemorrhagic presentation.

CONCLUSIONS

By using an ML approach, the authors found predictors of hemorrhagic presentation that were not identified using a conventional regression approach.