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Kpegeol CK, Jain VS, Ansari D, Ammanuel SG, Page PS, Josiah DT. Surgical site infection rates in open versus endoscopic lumbar spinal decompression surgery: A retrospective cohort study. World Neurosurg X 2024; 22:100347. [PMID: 38440381 PMCID: PMC10911845 DOI: 10.1016/j.wnsx.2024.100347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 12/04/2023] [Accepted: 02/21/2024] [Indexed: 03/06/2024] Open
Abstract
Background Lumbar decompression is a commonly performed procedure for the operative management of several degenerative lumbar spinal pathologies. Although open approaches are considered the traditional method, endoscopic techniques represent a relatively novel, less-invasive option to achieve neural element decompression. Here within, we examine if the use of endoscopic techniques decreases the risk of post operative infections. Methods We performed a retrospective cohort analysis to directly compare patients who underwent either open or endoscopic lumbar decompression at a single institution. Rates of postoperative outcomes such as surgical site infection, hospital length of stay, estimated blood loss, and others were compared between the two treatment groups. A multivariate logistic regression model was constructed using patient comorbidities and procedural characteristics to identify the risk factors for surgical site infection. Results 150 patients were identified as undergoing lumbar spine decompression surgeries that met inclusion criteria for the study, of whom 108 (72.0%) underwent open and 61 (28.0%) underwent endoscopic approaches. Unpaired analysis revealed positive associations between operative duration, estimated blood loss, drain placement rates. Multivariate logistic regression did not reveal an association between surgical approach (open versus endoscopic) and the development of surgical site infection. Conclusions Surgical site infections following endoscopic lumbar spine decompression are relatively uncommon, however, after adjusting for baseline differences between patient populations, surgical approach does not independently predict the development of postoperative infection.
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Affiliation(s)
| | | | - Darius Ansari
- Department of Neurological Surgery, University of Wisconsin Hospital and Clinics, Madison, WI, 53792, USA
| | - Simon G. Ammanuel
- Department of Neurological Surgery, University of Wisconsin Hospital and Clinics, Madison, WI, 53792, USA
| | - Paul S. Page
- Department of Neurological Surgery, University of Wisconsin Hospital and Clinics, Madison, WI, 53792, USA
| | - Darnell T. Josiah
- Department of Neurological Surgery, University of Wisconsin Hospital and Clinics, Madison, WI, 53792, USA
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Luu CP, Ammanuel SG, Mohis M, Schmidt B, Stadler JA. The Re-Evaluation of Frailty in Predicting Complications after Long-Segment Spinal Fusion for Adult Spinal Deformity. World Neurosurg 2024; 183:e415-e420. [PMID: 38154681 DOI: 10.1016/j.wneu.2023.12.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 12/30/2023]
Abstract
OBJECTIVE To evaluate on a national scale how frailty status (stratified using the 5-item Modified Frailty Index (mFI-5)) affects the operative characteristics of and complications after long-segment spinal fusion (LSF) for adult spinal deformity (ASD). METHODS Adults undergoing LSF of ≥3 vertebrae in the National Surgical Quality Improvement Program database years 2015-2020 were split into 2 cohorts: nonfrail with mFI = 0 or 1; frail with mFI ≥2. Demographics, operative characteristics, and 30-day complications were contrasted between the cohorts using the Student's t-test, the Fisher's exact test, or a multivariate analysis when appropriate. RESULTS In the 340 LSF cases collected, 268 fell into the nonfrail cohort and 72 into the frail cohort. The frail cohort constituted a high rate of geriatric age (65.3% vs. 38.1%; P < 0.001), higher body mass index (32.9 ± 0.86 vs. 30.2 ± 0.39; P = 0.005), and more comorbidities in 9 of 14 measures. After surgery, the frail cohort experienced more urinary tract infections (odds ratio [OR], 3.33; confidence interval [CI], 1.01-10.94; P = 0.04). However, the frail cohort shared similarities with the nonfrail cohort in terms of length of stay (5.11 ± 0.51 vs. 6.01 ± 1.62 days; P = 0.60), home discharge (OR, 0.76; CI, 0.42-1.39; P = 0.38), readmission (OR, 2.45; CI, 0.87-6.89; P = 0.09), and overall rate of complications (OR, 0.89; CI, 0.50-1.59; P = 0.70). CONCLUSIONS Despite trends found in past studies of ASD, this analysis showed that the frailty status of mFI ≥2 is a poor predictor of surgical and hospitalization course and overall complications in LSF when examined up to 30 days postoperatively.
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Affiliation(s)
- Cuong P Luu
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA.
| | - Simon G Ammanuel
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Momin Mohis
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Bradley Schmidt
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - James A Stadler
- Department of Neurosurgery, University of Wisconsin-Madison, Madison, Wisconsin, USA
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Ammanuel SG, Kondapavulur S, Lu AY, Breshears JD, Clark JP, Silva AB, Chang EF. Intraoperative cortical stimulation mapping with laryngeal electromyography for the localization of human laryngeal motor cortex. J Neurosurg 2024:1-10. [PMID: 38181494 DOI: 10.3171/2023.10.jns231023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/11/2023] [Indexed: 01/07/2024]
Abstract
OBJECTIVE The objectives of this study were to describe the authors' clinical methodology and outcomes for mapping the laryngeal motor cortex (LMC) and define localization of the LMC in a cohort of neurosurgical patients undergoing intraoperative brain mapping. Because of mapping variability across patients, the authors aimed to define the probabilistic distribution of cortical sites that evoke laryngeal movement, as well as adjacent cortical somatotopic representations for the face (mouth), tongue, and hand. METHODS Thirty-six patients underwent left (n = 18) or right (n = 18) craniotomy with asleep motor mapping. For each patient, electromyography (EMG) electrodes were placed in the face, tongue, and hand; a nerve integrity monitor (NIM) endotracheal tube with surface electrodes detected EMG activity from the bilateral vocal folds. After dense cortical stimulation was delivered throughout the sensorimotor cortex, motor responses were then mapped onto a three-dimensional reconstruction of the patient's cortical surfaces for location characterization of the evoked responses. Finally, stimulation sites were transformed into a two-dimensional coordinate system for probabilistic mapping of the stimulation site relative to the central sulcus and sylvian fissure. RESULTS The authors found that the LMC was predominantly localized to a mid precentral gyrus region, dorsal to face representation and surrounding a transverse sulcus ventral to the hand knob. In 14 of 36 patients, the authors identified additional laryngeal responses located ventral to all orofacial representations, providing evidence for dual LMC representations. CONCLUSIONS The authors determined the probabilistic distribution of the LMC. Cortical stimulation mapping with an NIM endotracheal tube is an easy and effective method for mapping the LMC and is simply integrated into the current neuromonitoring methods for brain mapping.
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Affiliation(s)
- Simon G Ammanuel
- 1Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin
| | | | - Alex Y Lu
- Departments of2Neurological Surgery and
| | - Jonathan D Breshears
- 3Marion Bloch Neuroscience Institute, Saint Luke's Hospital, Kansas City, Missouri; and
| | - John P Clark
- 5Surgical Neurophysiology, University of California, San Francisco, California
| | | | - Edward F Chang
- Departments of2Neurological Surgery and
- 4Center for Integrative Neuroscience, University of California, San Francisco, California
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Ammanuel SG, Page PS, Brooks NP, Resnick DK. Development of a Predictive Model for Persistent Instability Following Conservative Management of Type II Odontoid Fractures. World Neurosurg 2024; 181:e422-e426. [PMID: 37863424 DOI: 10.1016/j.wneu.2023.10.073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 10/22/2023]
Abstract
BACKGROUND Odontoid fractures are common cervical spine fractures; however, significant controversy exists regarding their treatment. Risk factors for failure of conservative therapy have been identified, although no predictive risk score has been developed to aid in decision-making. METHODS A retrospective review was conducted of all patients evaluated at a level 1 trauma center. Patients identified with type II odontoid fractures as classified by the D'Alonzo Classification system who were treated with external orthosis were included in analysis. Patients were considered to have failed conservative therapy if they were offered surgical intervention. A machine learning method (Risk-SLIM) was then utilized to create a risk stratification score based on risk factors to identify patients at high risk for requiring surgical intervention due to persistent instability. RESULTS A total of 138 patients were identified as presenting with type II odontoid fractures that were treated conservatively; 38 patients were offered surgery for persistent instability. The Odontoid Fracture Predictive Model (OFPM) was created using a machine learning algorithm with a 5-fold cross validation area under the curve of 0.7389 (95% CI: 0.671 to 0.808). Predictive factors were found to include fracture displacement, displacement greater than 5 mm, comminution at the fracture base, and history of smoking. The probability of persistent instability was <5% with a score of 0 and 88% with a score of 5. CONCLUSIONS The OFPM model is a unique, quick, and accurate tool to assist in clinical decision-making in patients with type II odontoid fractures. External validation is necessary to evaluate the validity of these findings.
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Affiliation(s)
- Simon G Ammanuel
- Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, Wisconsin, USA.
| | - Paul S Page
- Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, Wisconsin, USA
| | - Nathaniel P Brooks
- Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, Wisconsin, USA
| | - Daniel K Resnick
- Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, Wisconsin, USA
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Page P, Ammanuel SG, Brooks NP, Resnick DK. 335 Development and Validation of a Predictive Score for Persistent Instability Following Conservative Treatment in Type II Odontoid Fractures. Neurosurgery 2023. [DOI: 10.1227/neu.0000000000002375_335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
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Page P, Greeneway G, Ammanuel SG, Resnick DK. 121 Development and Validation of a Predictive Score for Lumbar Synovial Cyst Recurrence. Neurosurgery 2023. [DOI: 10.1227/neu.0000000000002375_121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
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Greeneway GP, Page PS, Ammanuel SG, Hanna AS. Lateral femoral cutaneous nerve transposition. Neurosurg Focus Video 2023; 8:V8. [PMID: 36628093 PMCID: PMC9815206 DOI: 10.3171/2022.10.focvid2289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 10/03/2022] [Indexed: 01/02/2023]
Abstract
Lateral femoral cutaneous neuropathy, also known as meralgia paresthetica, is a pathology commonly encountered by neurosurgeons. Symptoms include numbness, tingling, and burning pain over the anterolateral thigh due to impingement on the lateral femoral cutaneous nerve (LFCN). Surgical treatment has traditionally involved nerve release or neurectomy. LFCN transposition is a relatively new approach that can provide excellent symptomatic relief. In this video, the authors highlight key operative techniques to ensure easy identification, adequate decompression, and transposition of the nerve. Key steps include ultrasound-guided wire localization, superficial decompression, opening of the inguinal ligament, deep decompression, and medial transposition. The video can be found here: https://stream.cadmore.media/r10.3171/2022.10.FOCVID2289.
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Page PS, Greeneway GP, Ammanuel SG, Resnick DK. Creation and validation of a predictive model for lumbar synovial cyst recurrence following decompression without fusion. J Neurosurg Spine 2022; 37:851-854. [PMID: 35907198 DOI: 10.3171/2022.5.spine22504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 05/27/2022] [Indexed: 11/06/2022]
Abstract
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.
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Jain VS, Kpegeol C, Ammanuel SG, Page PS, Josiah DT. Early Outcomes Following Elective Laminoplasty: A Comparison of Surgical Specialties using the National Surgical Quality Improvement Program (NSQIP) Database. Interdisciplinary Neurosurgery 2022. [DOI: 10.1016/j.inat.2022.101700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Saggi S, Winkler EA, Ammanuel SG, Morshed RA, Garcia JH, Young JS, Semonche A, Fullerton HJ, Kim H, Cooke DL, Hetts SW, Abla A, Lawton MT, Gupta N. Machine learning for predicting hemorrhage in pediatric patients with brain arteriovenous malformation. J Neurosurg Pediatr 2022; 30:203-209. [PMID: 35916099 DOI: 10.3171/2022.4.peds21470] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/11/2022] [Indexed: 11/06/2022]
Abstract
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.
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Affiliation(s)
- Satvir Saggi
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Ethan A Winkler
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Simon G Ammanuel
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Ramin A Morshed
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Joseph H Garcia
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Jacob S Young
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Alexa Semonche
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Heather J Fullerton
- 2Pediatric Stroke and Cerebrovascular Disease Center, Department of Neurology, University of California, San Francisco
| | - Helen Kim
- 3Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco
| | - Daniel L Cooke
- 4Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Steven W Hetts
- 4Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Adib Abla
- 1Department of Neurological Surgery, University of California, San Francisco
| | - Michael T Lawton
- 5Department of Neurological Surgery, Barrow Neurological Institute, Phoenix, Arizona; and
| | - Nalin Gupta
- 1Department of Neurological Surgery, University of California, San Francisco.,6Department of Pediatrics, University of California, San Francisco, California
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Page PS, Ammanuel SG, Josiah DT. Evaluation of Endoscopic Versus Open Lumbar Discectomy: A Multi-Center Retrospective Review Utilizing the American College of Surgeons’ National Surgical Quality Improvement Program (ACS-NSQIP) Database. Cureus 2022; 14:e25202. [PMID: 35747045 PMCID: PMC9213256 DOI: 10.7759/cureus.25202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2022] [Indexed: 11/05/2022] Open
Abstract
Introduction: Endoscopic techniques in spine surgery continue to gain popularity due to their potential for decreased blood loss and post-operative pain. However, limited studies have evaluated these techniques within the United States. Additionally, given the limited number of practitioners with experience in endoscopy, most current studies are limited by a lack of heterogeneity. Methods: The American College of Surgeons’ National Surgical Quality Improvement Program (ACS-NSQIP) database was queried to evaluate the effect of endoscopic surgery on adverse events. Current Procedural Terminology (CPT) codes for open discectomy were compared with the relevant CPT codes for endoscopic lumbar discectomy. Baseline patient characteristics and adverse outcomes were then compared. Results: A total of 38,497 single-level lumbar discectomies were identified and included. Of these, 175 patients undergoing endoscopic discectomy were compared with 38,322 patients undergoing open discectomy. Endoscopic discectomy demonstrated a shorter operative time of 88.6 minutes than 92.1 minutes in the open group. However, this was not significant (p=0.08). Patients in the endoscopic group demonstrated a shorter total length of stay of 0.81 days vs 1.15 days (p=0.014). Total adverse events were lower in the endoscopic group at 0.6% vs 3.4% in the open group (p=0.03). Conclusion: Endoscopic discectomy demonstrated a significantly lower rate of adverse events and shorter total length of stay than open discectomy. Further research is necessary over time to evaluate larger patient populations as this technology is more rapidly incorporated.
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Page PS, Greeneway GP, Ammanuel SG, Brooks NP. Development and Validation of a Predictive Model for Failure of Medical Management in Spinal Epidural Abscesses. Neurosurgery 2022; 91:422-426. [PMID: 35584275 DOI: 10.1227/neu.0000000000002043] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 04/03/2022] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The optimal management of spinal epidural abscesses (SEA) secondary to primary spinal infections has demonstrated large variability in the literature. Although some literature suggests a high rate of neurological deterioration, others suggest failure of medical management is uncommon. OBJECTIVE To develop a predictive model to evaluate the likelihood of failure of medical therapy in the setting of SEA. METHODS A retrospective review was conducted of all patients presenting with SEA from primary spinal infections. Patients presenting with MRI evidence of SEA without neurological deficits were included. Failure of medical management was defined as requiring surgical intervention over 72 hours after the initiation of antibiotics. A machine learning method (Risk-Calibrated Supersparse Linear Integer Model) was used to create a risk stratification score to identify patients at high risk for requiring surgical intervention. RESULTS In total, 159 patients were identified as presenting with MRI findings of SEA without evidence of neurological deficit. Of these patients, 50 required delayed surgery compared with 109 whose infection were successfully treated with surgical intervention. The Spinal Epidural Abscess Predictive Score was created using a machine learning model with an area under the curve of 0.8043 with calibration error of 14.7%. Factors included active malignancy, spondylodiscitis, organism identification, blood cultures, and sex. The probability of failure of medical management ranged from <5% for a score of 2 or less and >95% for a score of 7 or more. CONCLUSION The Spinal Epidural Abscess Predictive Score model is a quick and accurate tool to assist in clinical decision-making in SEA.
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Affiliation(s)
- Paul S Page
- Department of Neurological Surgery, University of Wisconsin Hospitals and Clinics, Madison, Wisconsin, USA
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Kim JJ, Li C, Ammanuel SG, Elbayomy AM, Page PS, Ahmed AS. Candida Shunt Infection Causing Arachnoiditis and Hydrocephalus: A Case Report. Cureus 2022; 14:e23675. [PMID: 35510023 PMCID: PMC9060725 DOI: 10.7759/cureus.23675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2022] [Indexed: 11/22/2022] Open
Abstract
Arachnoiditis is a relatively rare condition and can result in long-term chronic and debilitating complications if not diagnosed early and treated properly. However, diagnosis of arachnoiditis is rare and knowledge of potential causes of this condition is still sparse. Current known causes of arachnoiditis include infections, trauma, spinal tumors, and iatrogenic causes induced via neurological interventions. Here, we present a case of a 65-year-old female who presented with arachnoiditis caused by Candida albicans infection from a contaminated ventriculoperitoneal (VP) shunt, placed following the development of hydrocephalus from subarachnoid hemorrhage. During her initial assessment, the possibility of arachnoiditis was raised after spinal magnetic resonance imaging (MRI) due to leg weakness and spasms with bladder dysfunction. However, further workup was not pursued after a normal spinal angiogram and lack of constitutional symptoms. She presented six months later with symptoms of fever and lower abdominal pain. She was diagnosed with fungal arachnoiditis after a computerized tomography (CT) of the abdomen showed thickening of the fascia around the shunt catheter and fluid collections near the tip of the shunt in the abdominal cavity after hospitalization. The diagnosis was made after an ultrasound-guided tap of the same area revealed budding yeast and cerebrospinal fluid (CSF) showed growths of Candida albicans. Her shunt was removed, and she received intravenous (IV) antifungals and recovered. MRI should be considered with clinical presentations that are characteristic of arachnoiditis. Symptoms from fungal infections are usually dramatic; however, in some instances as in this case, they may follow a more progressive course. The patient should be extensively evaluated for infection, especially fungal, in interventions involving device placement even when minimally, but persistently, symptomatic.
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Ammanuel SG, Almeida NC, Kurteff G, Kakaizada S, Molinaro AM, Berger MS, Chang EF, Hervey-Jumper SL. Correlation of natural language assessment results with health-related quality of life in adult glioma patients. J Neurosurg 2022; 136:343-349. [PMID: 34330100 PMCID: PMC10182825 DOI: 10.3171/2021.1.jns203387] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 01/22/2021] [Indexed: 11/06/2022]
Abstract
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.
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Affiliation(s)
| | | | - Garret Kurteff
- 1Department of Neurological Surgery and.,2Department of Communication Sciences & Disorders, University of Texas, Austin, Texas
| | | | | | | | - Edward F Chang
- 1Department of Neurological Surgery and.,3Center for Integrative Neuroscience, University of California, San Francisco, California; and
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Garcia JH, Winkler EA, Morshed RA, Lu A, Ammanuel SG, Saggi S, Wang EJ, Braunstein S, Fox CK, Fullerton HJ, Kim H, Cooke DL, Hetts SW, Lawton MT, Abla AA, Gupta N. Factors associated with seizures at initial presentation in pediatric patients with cerebral arteriovenous malformations. J Neurosurg Pediatr 2021:1-6. [PMID: 34560640 DOI: 10.3171/2021.6.peds21126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/07/2021] [Indexed: 11/06/2022]
Abstract
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.
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Affiliation(s)
- Joseph H Garcia
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Ethan A Winkler
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Ramin A Morshed
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Alex Lu
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Simon G Ammanuel
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Satvir Saggi
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Elaina J Wang
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Steve Braunstein
- 2Department of Radiation Oncology, University of California San Francisco, San Francisco
| | - Christine K Fox
- 3Pediatric Stroke and Cerebrovascular Disease Center, Department of Neurology, University of California San Francisco, San Francisco
| | - Heather J Fullerton
- 3Pediatric Stroke and Cerebrovascular Disease Center, Department of Neurology, University of California San Francisco, San Francisco
| | - Helen Kim
- 4Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco
| | - Daniel L Cooke
- 5Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco
| | - Steven W Hetts
- 5Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco
| | - Michael T Lawton
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco.,6Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona
| | - Adib A Abla
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco
| | - Nalin Gupta
- 1Department of Neurological Surgery, University of California San Francisco, San Francisco.,7Department of Pediatrics, University of California San Francisco, San Francisco, California; and
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16
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Nnamani Silva ON, Ammanuel SG, Segobiano BM, Edwards CS, Hoffman WY. Assessing the Readability of Online Patient Education Resources Related to Gynecomastia. Ann Plast Surg 2021; 87:123-125. [PMID: 33346559 DOI: 10.1097/sap.0000000000002620] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The Internet has a plethora of online patient education resources for many symptoms and diseases. National medical governing bodies recommend that patient education materials are written at or below the eighth-grade level, and the literature suggests that health literacy has been linked to increased adherence to treatment regimens and improved outcomes. The primary aim of the study is to assess the readability of online patient materials relating to gynecomastia and ascertain the availability of patient materials in non-English languages. METHODS The readability of patient education materials relating to gynecomastia for academic-based websites and nonacademic websites was assessed using the Flesch Reading Ease (FRE), Flesch-Kincaid Grade Level (FKGL), and Simple Measure of Gobbledygook (SMOG). The prevalence of non-English patient education materials was assessed for both academic-based and nonacademic websites. RESULTS Fifty-eight documents were collected across academic websites. Overall median values were 10.7 for the FKGL, 47.0 for the FRE, and 11.4 for the SMOG. For the 10 nonacademic institutions, the overall median values were 10.6 for the FKGL, 45.2 for the FRE, and 10.8 for the SMOG. No appreciable differences were observed for readability when stratified by region or source. The prevalence of non-English patient materials was 19.1% across institutions. None of the noninstitutional materials had information in non-English languages. CONCLUSIONS The readability of patient education materials related to gynecomastia is at higher levels than recommended by national organizations. There are limited non-English patient education materials. Future efforts should focus on improving the readability and accessibility of patient materials.
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Affiliation(s)
| | - Simon G Ammanuel
- From the University of California, San Francisco School of Medicine, San Francisco, CA
| | - Brett M Segobiano
- College of Arts and Letters, University of Notre Dame, South Bend, IN
| | - Caleb S Edwards
- From the University of California, San Francisco School of Medicine, San Francisco, CA
| | - William Y Hoffman
- Division of Plastic and Reconstructive Surgery, Department of Surgery, University of California, San Francisco, San Francisco, CA
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17
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Ammanuel SG, Edwards CS, Chan AK, Mummaneni PV, Kidane J, Vargas E, D’Souza S, Nichols AD, Sankaran S, Abla AA, Aghi MK, Chang EF, Hervey-Jumper SL, Kunwar S, Larson PS, Lawton MT, Starr PA, Theodosopoulos PV, Berger MS, McDermott MW. Are preoperative chlorhexidine gluconate showers associated with a reduction in surgical site infection following craniotomy? A retrospective cohort analysis of 3126 surgical procedures. J Neurosurg 2021; 135:1889-1897. [PMID: 33930864 PMCID: PMC9448162 DOI: 10.3171/2020.10.jns201255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 10/01/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Surgical site infection (SSI) is a complication linked to increased costs and length of hospital stay. Prevention of SSI is important to reduce its burden on individual patients and the healthcare system. The authors aimed to assess the efficacy of preoperative chlorhexidine gluconate (CHG) showers on SSI rates following cranial surgery. METHODS In November 2013, a preoperative CHG shower protocol was implemented at the authors' institution. A total of 3126 surgical procedures were analyzed, encompassing a time frame from April 2012 to April 2016. Cohorts before and after implementation of the CHG shower protocol were evaluated for differences in SSI rates. RESULTS The overall SSI rate was 0.6%. No significant differences (p = 0.11) were observed between the rate of SSI of the 892 patients in the preimplementation cohort (0.2%) and that of the 2234 patients in the postimplementation cohort (0.8%). Following multivariable analysis, implementation of preoperative CHG showers was not associated with decreased SSI (adjusted OR 2.96, 95% CI 0.67-13.1; p = 0.15). CONCLUSIONS This is the largest study, according to sample size, to examine the association between CHG showers and SSI following craniotomy. CHG showers did not significantly alter the risk of SSI after a cranial procedure.
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Affiliation(s)
- Simon G. Ammanuel
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Caleb S. Edwards
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Andrew K. Chan
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Praveen V. Mummaneni
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Joseph Kidane
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Enrique Vargas
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Sarah D’Souza
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Amy D. Nichols
- Department of Hospital Epidemiology and Infection Control, University of California, San Francisco, California
| | - Sujatha Sankaran
- Department of Hospital Medicine, University of California, San Francisco, California
| | - Adib A. Abla
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Manish K. Aghi
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Edward F. Chang
- Department of Neurological Surgery, University of California, San Francisco, California
| | | | - Sandeep Kunwar
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Paul S. Larson
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Michael T. Lawton
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Philip A. Starr
- Department of Neurological Surgery, University of California, San Francisco, California
| | | | - Mitchel S. Berger
- Department of Neurological Surgery, University of California, San Francisco, California
| | - Michael W. McDermott
- Department of Neurological Surgery, University of California, San Francisco, California
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18
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Rehani B, Rodriguez JA, Nguyen JK, Patel MM, Ammanuel SG, Winford E, Dillon WP. COVID-19 Radiology Preparedness, Challenges & Opportunities: Responses From 18 Countries. Curr Probl Diagn Radiol 2021; 51:196-203. [PMID: 33994227 PMCID: PMC8064895 DOI: 10.1067/j.cpradiol.2021.03.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 03/16/2021] [Accepted: 03/22/2021] [Indexed: 11/23/2022]
Abstract
Purpose Radiology departments around the world have been faced with the challenge to adapt, and recover to the COVID-19 pandemic. This study is part of a worldwide survey of radiologists' responses to COVID-19 in 18 different countries in Africa, Asia, Europe, and Latin America. The purpose of this study is to analyze the changes made in international radiology departments and practices in response to the pandemic. Methods The 18-item survey was sent via email from April to May 2020 to radiologists in Africa, Asia, Europe, and Latin America to assess their response to COVID-19. Our survey included questions regarding imaging, workforce adjustments, testing availability, staff and patient safety, research and education, and infrastructure availability. Results Twenty-eight survey responses were reviewed. Of the 28 respondents, 42.9% have shortages of infrastructure and 78.6% responded that COVID-19 testing was available. Regarding the use of Chest CT in COVID-19 patients, 28.6% respondents used Chest CT as screening for COVID-19. For staff safety, interventions included encouraging use of masks in patient encounters, social distancing and PPE training. To cope with their education and research mission, radiology departments are doing online lectures, reducing the number of residents in rotations, and postponing any non-urgent activities. Conclusion In conclusion, there are disparities in infrastructure, research, and educational initiatives during COVID-19 which also provides opportunity for the global radiology community to work together on these issues.
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Affiliation(s)
- Bhavya Rehani
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA.
| | - Jose A Rodriguez
- Faculty of Medical Sciences, Universidad Nacional Autonoma de Honduras, Tegucigalpa, Honduras
| | - Jeffers K Nguyen
- Department of Radiology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY
| | - Mauli M Patel
- Wayne State University School of Medicine, Detroit, MI
| | - Simon G Ammanuel
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA
| | | | - William P Dillon
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA
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19
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Kleen JK, Speidel BA, Baud MO, Rao VR, Ammanuel SG, Hamilton LS, Chang EF, Knowlton RC. Accuracy of omni-planar and surface casting of epileptiform activity for intracranial seizure localization. Epilepsia 2021; 62:947-959. [PMID: 33634855 PMCID: PMC8276628 DOI: 10.1111/epi.16841] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/23/2021] [Accepted: 01/23/2021] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Intracranial electroencephalography (ICEEG) recordings are performed for seizure localization in medically refractory epilepsy. Signal quantifications such as frequency power can be projected as heatmaps on personalized three-dimensional (3D) reconstructed cortical surfaces to distill these complex recordings into intuitive cinematic visualizations. However, simultaneously reconciling deep recording locations and reliably tracking evolving ictal patterns remain significant challenges. METHODS We fused oblique magnetic resonance imaging (MRI) slices along depth probe trajectories with cortical surface reconstructions and projected dynamic heatmaps using a simple mathematical metric of epileptiform activity (line-length). This omni-planar and surface casting of epileptiform activity approach (OPSCEA) thus illustrated seizure onset and spread among both deep and superficial locations simultaneously with minimal need for signal processing supervision. We utilized the approach on 41 patients at our center implanted with grid, strip, and/or depth electrodes for localizing medically refractory seizures. Peri-ictal data were converted into OPSCEA videos with multiple 3D brain views illustrating all electrode locations. Five people of varying expertise in epilepsy (medical student through epilepsy attending level) attempted to localize the seizure-onset zones. RESULTS We retrospectively compared this approach with the original ICEEG study reports for validation. Accuracy ranged from 73.2% to 97.6% for complete or overlapping onset lobe(s), respectively, and ~56.1% to 95.1% for the specific focus (or foci). Higher answer certainty for a given case predicted better accuracy, and scorers had similar accuracy across different training levels. SIGNIFICANCE In an era of increasing stereo-EEG use, cinematic visualizations fusing omni-planar and surface functional projections appear to provide a useful adjunct for interpreting complex intracranial recordings and subsequent surgery planning.
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Affiliation(s)
- Jonathan K Kleen
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Benjamin A Speidel
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Maxime O Baud
- Department of Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Vikram R Rao
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Simon G Ammanuel
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Liberty S Hamilton
- Department of Speech, Language, and Hearing Sciences and Department of Neurology, The University of Texas at Austin, Austin, Texas, USA
| | - Edward F Chang
- Department of Neurological Surgery and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
| | - Robert C Knowlton
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, California, USA
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20
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Ammanuel SG, Edwards CS, Chan AK, Mummaneni PV, Kidane J, Vargas E, D’Souza S, Nichols AD, Sankaran S, Abla AA, Aghi MK, Chang EF, Her vey-Jumper SL, Kunwar SM, Larson PS, Lawton MT, Starr PA, Theodosopoulos PV, Berger MS, McDermott MW. Preoperative Chlorhexidine Showers Are Not Associated With a Reduction in Surgical Site Infection Following Craniotomy. Neurosurgery 2020. [DOI: 10.1093/neuros/nyaa447_139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Chan AK, Ammanuel SG, Chan AY, Oh T, Skrehot HC, Edwards CS, Kondapavulur S, Miller CA, Nichols AD, Liu C, Dhall SS, Clark AJ, Chou D, Ames CP, Mummaneni PV. Chlorhexidine Showers are Associated With a Reduction in Surgical Site Infection Following Spine Surgery: An Analysis of 4266 Consecutive Surgeries. Neurosurgery 2020; 85:817-826. [PMID: 30590721 DOI: 10.1093/neuros/nyy568] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 11/05/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Surgical site infection (SSI) is a common complication following spinal surgery. Prevention is critical to maintaining safe patient care and reducing additional costs associated with treatment. OBJECTIVE To determine the efficacy of preoperative chlorhexidine (CHG) showers on SSI rates following fusion and nonfusion spine surgery. METHODS A mandatory preoperative CHG shower protocol was implemented at our institution in November 2013. A cohort comparison of 4266 consecutive patients assessed differences in SSI rates for the pre- and postimplementation periods. Subgroup analysis was performed on the type of spinal surgery (eg, fusion vs nonfusion). Data represent all spine surgeries performed between April 2012 and April 2016. RESULTS The overall mean SSI rate was 0.4%. There was no significant difference between the pre- (0.7%) and postimplementation periods (0.2%; P = .08). Subgroup analysis stratified by procedure type showed that the SSI rate for the nonfusion patients was significantly lower in the post- (0.1%) than the preimplementation group (0.7%; P = .02). There was no significant difference between SSI rates for the pre- (0.8%) and postimplementation groups (0.3%) for the fusion cohort (P = .21). In multivariate analysis, the implementation of preoperative CHG showers were associated with significantly decreased odds of SSI (odds ratio = 0.15, 95% confidence interval [0.03-0.55], P < .01). CONCLUSION This is the largest study investigating the efficacy of preoperative CHG showers on SSI following spinal surgery. In adjusted multivariate analysis, CHG showering was associated with a significant decrease in SSI following spinal surgery.
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Affiliation(s)
- Andrew K Chan
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Simon G Ammanuel
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Alvin Y Chan
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Taemin Oh
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Henry C Skrehot
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Caleb S Edwards
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Sravani Kondapavulur
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Catherine A Miller
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Amy D Nichols
- Department of Hospital Epidemiology and Infection Control, University of California, San Francisco, San Francisco, California
| | - Catherine Liu
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Institute and Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington
| | - Sanjay S Dhall
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Aaron J Clark
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Dean Chou
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Christopher P Ames
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
| | - Praveen V Mummaneni
- Department of Neurosurgery, University of California, San Francisco, San Francisco, California
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22
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Winkler EA, Lu A, Morshed RA, Yue JK, Rutledge WC, Burkhardt JK, Patel AB, Ammanuel SG, Braunstein S, Fox CK, Fullerton HJ, Kim H, Cooke D, Hetts SW, Lawton MT, Abla AA, Gupta N. Bringing high-grade arteriovenous malformations under control: clinical outcomes following multimodality treatment in children. J Neurosurg Pediatr 2020; 26:82-91. [PMID: 32276243 DOI: 10.3171/2020.1.peds19487] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 01/20/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Brain arteriovenous malformations (AVMs) consist of dysplastic blood vessels with direct arteriovenous shunts that can hemorrhage spontaneously. In children, a higher lifetime hemorrhage risk must be balanced with treatment-related morbidity. The authors describe a collaborative, multimodal strategy resulting in effective and safe treatment of pediatric AVMs. METHODS A retrospective analysis of a prospectively maintained database was performed in children with treated and nontreated pediatric AVMs at the University of California, San Francisco, from 1998 to 2017. Inclusion criteria were age ≤ 18 years at time of diagnosis and an AVM confirmed by a catheter angiogram. RESULTS The authors evaluated 189 pediatric patients with AVMs over the study period, including 119 ruptured (63%) and 70 unruptured (37%) AVMs. The mean age at diagnosis was 11.6 ± 4.3 years. With respect to Spetzler-Martin (SM) grade, there were 38 (20.1%) grade I, 40 (21.2%) grade II, 62 (32.8%) grade III, 40 (21.2%) grade IV, and 9 (4.8%) grade V lesions. Six patients were managed conservatively, and 183 patients underwent treatment, including 120 resections, 82 stereotactic radiosurgery (SRS), and 37 endovascular embolizations. Forty-four of 49 (89.8%) high-grade AVMs (SM grade IV or V) were treated. Multiple treatment modalities were used in 29.5% of low-grade and 27.3% of high-grade AVMs. Complete angiographic obliteration was obtained in 73.4% of low-grade lesions (SM grade I-III) and in 45.2% of high-grade lesions. A periprocedural stroke occurred in a single patient (0.5%), and there was 1 treatment-related death. The mean clinical follow-up for the cohort was 4.1 ± 4.6 years, and 96.6% and 84.3% of patients neurologically improved or remained unchanged in the ruptured and unruptured AVM groups following treatment, respectively. There were 16 bleeding events following initiation of AVM treatment (annual rate: 0.02 events per person-year). CONCLUSIONS Coordinated multidisciplinary evaluation and individualized planning can result in safe and effective treatment of children with AVMs. In particular, it is possible to treat the majority of high-grade AVMs with an acceptable safety profile. Judicious use of multimodality therapy should be limited to appropriately selected patients after thorough team-based discussions to avoid additive morbidity. Future multicenter studies are required to better design predictive models to aid with patient selection for multimodal pediatric care, especially with high-grade AVMs.
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Affiliation(s)
| | - Alex Lu
- Departments of1Neurological Surgery
| | | | | | | | - Jan-Karl Burkhardt
- Departments of1Neurological Surgery.,2Department of Neurosurgery, Baylor Medical Center, Houston, Texas; and
| | | | | | | | - Christine K Fox
- 4Pediatric Stroke and Cerebrovascular Disease Center, Department of Neurology; and
| | - Heather J Fullerton
- 4Pediatric Stroke and Cerebrovascular Disease Center, Department of Neurology; and
| | - Helen Kim
- 5Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, California
| | | | | | - Michael T Lawton
- Departments of1Neurological Surgery.,7Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona
| | | | - Nalin Gupta
- Departments of1Neurological Surgery.,8Pediatrics
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23
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Ammanuel SG, Kleen JK, Leonard MK, Chang EF. Interictal Epileptiform Discharges and the Quality of Human Intracranial Neurophysiology Data. Front Hum Neurosci 2020; 14:44. [PMID: 32194384 PMCID: PMC7062638 DOI: 10.3389/fnhum.2020.00044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/31/2020] [Indexed: 12/25/2022] Open
Abstract
Intracranial electroencephalography (IEEG) involves recording from electrodes placed directly onto the cortical surface or deep brain locations. It is performed on patients with medically refractory epilepsy, undergoing pre-surgical seizure localization. IEEG recordings, combined with advancements in computational capacity and analysis tools, have accelerated cognitive neuroscience. This Perspective describes a potential pitfall latent in many of these recordings by virtue of the subject population—namely interictal epileptiform discharges (IEDs), which can cause spurious results due to the contamination of normal neurophysiological signals by pathological waveforms related to epilepsy. We first discuss the nature of IED hazards, and why they deserve the attention of neurophysiology researchers. We then describe four general strategies used when handling IEDs (manual identification, automated identification, manual-automated hybrids, and ignoring by leaving them in the data), and discuss their pros, cons, and contextual factors. Finally, we describe current practices of human neurophysiology researchers worldwide based on a cross-sectional literature review and a voluntary survey. We put these results in the context of the listed strategies and make suggestions on improving awareness and clarity of reporting to enrich both data quality and communication in the field.
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Affiliation(s)
- Simon G Ammanuel
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Jonathan K Kleen
- Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, United States
| | - Matthew K Leonard
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Edward F Chang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
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24
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Ammanuel SG, Chan AK, DiGiorgio AM, Alazzeh M, Nwachuku K, Robinson LC, Lobo E, Mummaneni PV. Perioperative Anesthesia Lean Implementation Is Associated With Increased Operative Efficiency in Posterior Cervical Surgeries at a HighVolume Spine Center. Neurospine 2020; 17:390-397. [PMID: 32054140 PMCID: PMC7338954 DOI: 10.14245/ns.1938318.159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 01/06/2020] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Lean management strategies aim to increase efficiency by eliminating waste or by improving processes to optimize value. The operating room (OR) is an arena where these strategies can be implemented. We assessed changes in OR efficiency after the application of lean methodology on perioperative anesthesia associated with posterior cervical spine surgeries. METHODS We utilized pre- and post-lean study design to identify inefficiencies during the perioperative anesthesia process and implemented strategies to improve the process. Patient characteristics were recorded to assess for differences between the 2 groups (group 1, prelean; group 2, post-lean). In the pre-lean period, key steps in the perioperative anesthesia process were identified that were amenable to lean implementation. The time required for each identified key step was recorded by an independent study coordinator. The times for each step were then compared between the groups utilizing univariate analyses. RESULTS After lean implementation, there was a significant decrease in overall perioperative anesthesia process time (88.4 ± 4.7 minutes vs. 76.2 ± 3.2 minutes, p = 0.04). This was driven by significant decreases in the steps: transport and setup (10.4 ± 0.8 minutes vs. 8.0 ± 0.7 minutes, p = 0.03) and positioning (20.8 ± 2.1 minutes vs. 15.7 ± 1.3 minutes, p = 0.046). Of note, the total time spent in the OR was lower for group 2 (270.1 ± 14.6 minutes vs. 252.8 ± 14.1 minutes) but the result was not statistically significant, even when adjusting for number of operated levels. CONCLUSION Lean methodology may be successfully applied to posterior cervical spine surgery whereby improvements in the perioperative anesthetic process are associated with significantly increased OR efficiency.
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Affiliation(s)
- Simon G Ammanuel
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - Andrew K Chan
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - Anthony M DiGiorgio
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - Mohanad Alazzeh
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Kelechi Nwachuku
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - Leslie C Robinson
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - Errol Lobo
- Department of Anesthesiology, University of California San Francisco, San Francisco, CA, USA
| | - Praveen V Mummaneni
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
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25
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Deng H, Chan AK, Ammanuel SG, Chan AY, Oh T, Skrehot HC, Edwards CS, Kondapavulur S, Nichols AD, Liu C, Yue JK, Dhall SS, Clark AJ, Chou D, Ames CP, Mummaneni PV. Risk factors for deep surgical site infection following thoracolumbar spinal surgery. J Neurosurg Spine 2020. [DOI: 10.3171/2019.8.spine19479] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVESurgical 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.METHODSAll 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.RESULTSIn 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.CONCLUSIONSThis 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.
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Affiliation(s)
- Hansen Deng
- 1Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Andrew K. Chan
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Simon G. Ammanuel
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Alvin Y. Chan
- 3Department of Neurological Surgery, University of California, Irvine, California
| | - Taemin Oh
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Henry C. Skrehot
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Caleb S. Edwards
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Sravani Kondapavulur
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Amy D. Nichols
- 4Department of Hospital Epidemiology and Infection Control, University of California, San Francisco, California; and
| | - Catherine Liu
- 5Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Institute and Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington
| | - John K. Yue
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Sanjay S. Dhall
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Aaron J. Clark
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Dean Chou
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Christopher P. Ames
- 2Department of Neurological Surgery, University of California, San Francisco, California
| | - Praveen V. Mummaneni
- 2Department of Neurological Surgery, University of California, San Francisco, California
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Ammanuel SG, Edwards CS, Alhadi R, Hervey-Jumper SL. Readability of Online Neuro-Oncology–Related Patient Education Materials from Tertiary-Care Academic Centers. World Neurosurg 2020; 134:e1108-e1114. [DOI: 10.1016/j.wneu.2019.11.109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 10/25/2022]
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Rehani B, Ammanuel SG, Zhang Y, Smith W, Cooke DL, Hetts SW, Josephson SA, Kim A, Hemphill JC, Dillon W. A New Era of Extended Time Window Acute Stroke Interventions Guided by Imaging. Neurohospitalist 2019; 10:29-37. [PMID: 31839862 DOI: 10.1177/1941874419870701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Ischemic stroke is one of the most debilitating and deadliest conditions worldwide. Intravenous t-PA is the current standard treatment within 4 hours after onset of symptoms. Recent randomized controlled trials have demonstrated the efficacy of neurointerventional intra-arterial treatment in acute ischemic stroke. About 20% of acute ischemic stroke are classified as wake-up strokes, which falls out of the conventional treatment time window. New evidence suggests that some patients with longer time from symptom onset (up to 24 hours) may benefit from thrombectomy, probably in part due to variations in collateral circulation among individual patients. Advanced imaging can play a crucial role in identifying patients who could benefit from endovascular intervention presenting within extended treatment time windows. In this article, we review the advanced imaging algorithm for ischemic stroke workup in the multiple studies published to date and summarize the results of the clinical trials for late ischemic stroke that can be clinically useful.
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Affiliation(s)
- Bhavya Rehani
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
| | - Simon G Ammanuel
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
| | - Yi Zhang
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
| | - Wade Smith
- Department of Neurology, University of California San Francisco, CA, USA
| | - Daniel L Cooke
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
| | - Steven W Hetts
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
| | - S Andrew Josephson
- Department of Neurology, University of California San Francisco, CA, USA
| | - Anthony Kim
- Department of Neurology, University of California San Francisco, CA, USA
| | - J Claude Hemphill
- Department of Neurology, University of California San Francisco, CA, USA
| | - William Dillon
- Department of Radiology and Biomedical Imaging, University of California San Francisco, CA, USA
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Haraldsson H, Leach JR, Kao EI, Wright AG, Ammanuel SG, Khangura RS, Ballweber MK, Chin CT, Shah VN, Meisel K, Saloner DA, Amans MR. Reduced Jet Velocity in Venous Flow after CSF Drainage: Assessing Hemodynamic Causes of Pulsatile Tinnitus. AJNR Am J Neuroradiol 2019; 40:849-854. [PMID: 31023664 DOI: 10.3174/ajnr.a6043] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 03/18/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Idiopathic intracranial hypertension is commonly associated with transverse sinus stenosis, a venous cause of pulsatile tinnitus. In patients with idiopathic intracranial hypertension, CSF drainage via lumbar puncture decreases intracranial pressure, which relieves the stenosis, and may provide at least temporary cessation of pulsatile tinnitus. The objective of this study was to evaluate changes in venous blood flow caused by lowered intracranial pressure in patients with pulsatile tinnitus to help identify the cause of pulsatile tinnitus. MATERIALS AND METHODS Ten patients with suspected transverse sinus stenosis as a venous etiology for pulsatile tinnitus symptoms underwent MR imaging before and after lumbar puncture in the same session. The protocol included flow assessment and rating of pulsatile tinnitus intensity before and after lumbar puncture and MR venography before lumbar puncture. Post-lumbar puncture MR venography was performed in 1 subject. RESULTS There was a lumbar puncture-induced reduction in venous peak velocity that correlated with the opening pressure (r = -0.72, P = .019) without a concomitant reduction in flow rate. Patients with flow jets had their peak velocity reduced by 0.30 ± 0.18 m/s (P = .002), correlating with a reduction in CSF pressure (r = 0.82, P = .024) and the reduction in subjectively scored pulsatile tinnitus intensity (r = 0.78, P = .023). The post-lumbar puncture MR venography demonstrated alleviation of the stenosis. CONCLUSIONS Our results show a lumbar puncture-induced reduction in venous peak velocity without a concomitant reduction in flow rate. We hypothesize that the reduction is caused by the expansion of the stenosis after lumbar puncture. Our results further show a correlation between the peak velocity and pulsatile tinnitus intensity, suggesting the flow jet to be instrumental in the development of sound.
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Affiliation(s)
- H Haraldsson
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - J R Leach
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - E I Kao
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - A G Wright
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - S G Ammanuel
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - R S Khangura
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - M K Ballweber
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - C T Chin
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - V N Shah
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
| | - K Meisel
- Neurology (K.M.), University of California, San Francisco, San Francisco, California
| | - D A Saloner
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.).,Radiology Service (D.A.S.), VA Medical Center, San Francisco, California
| | - M R Amans
- From the Departments of Radiology and Biomedical Imaging (H.H., J.R.L., E.I.K., A.G.W., S.G.A., R.S.K., M.K.B., C.T.C., V.N.S., D.A.S., M.R.A.)
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