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  • Author or Editor: Michael Wongx
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George Kwok Chu Wong and Wai Sang Poon

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Alim P. Mitha, John H. Wong, Michael D. Hill, and Mayank Goyal

Open access

Alvin Wong, Arvin R. Wali, Bryan Ryba, Mihir Gupta, Michael L. Levy, and Amanda A. Gosman

Unicoronal craniosynostosis is notoriously difficult to treat, with long-term studies demonstrating high rates of relapse and the need for reoperation using open fronto-orbital advancement. Applying the principles of distraction osteogenesis to cranial vault remodeling has demonstrated promising short-term results that compare favorably with traditional methods, with simultaneous correction of both frontofacial and endocranial morphology, along with significant increases in intracranial volume. Here, the authors demonstrate their technique for rotation flap distraction osteogenesis in the treatment of unicoronal synostosis and provide case examples.

The video can be found here:https://vimeo.com/519505008.

Free access

Adela Wu, Michael C. Jin, Antonio Meola, Hong-nei Wong, and Steven D. Chang

OBJECTIVE

Adjuvant radiotherapy has become a common addition to the management of high-grade meningiomas, as immediate treatment with radiation following resection has been associated with significantly improved outcomes. Recent investigations into particle therapy have expanded into the management of high-risk meningiomas. Here, the authors systematically review studies on the efficacy and utility of particle-based radiotherapy in the management of high-grade meningioma.

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文学本身arch was developed by first defining the population, intervention, comparison, outcomes, and study design (PICOS). A search strategy was designed for each of three electronic databases: PubMed, Embase, and Scopus. Data extraction was conducted in accordance with the PRISMA guidelines. Outcomes of interest included local disease control, overall survival, and toxicity, which were compared with historical data on photon-based therapies.

RESULTS

Eleven retrospective studies including 240 patients with atypical (WHO grade II) and anaplastic (WHO grade III) meningioma undergoing particle radiation therapy were identified. Five of the 11 studies included in this systematic review focused specifically on WHO grade II and III meningiomas; the others also included WHO grade I meningioma. Across all of the studies, the median follow-up ranged from 6 to 145 months. Local control rates for high-grade meningiomas ranged from 46.7% to 86% by the last follow-up or at 5 years. Overall survival rates ranged from 0% to 100% with better prognoses for atypical than for malignant meningiomas. Radiation necrosis was the most common adverse effect of treatment, occurring in 3.9% of specified cases.

CONCLUSIONS

尽管缺乏随机前瞻性试验,this review of existing retrospective studies suggests that particle therapy, whether an adjuvant or a stand-alone treatment, confers survival benefit with a relatively low risk for severe treatment-derived toxicity compared to standard photon-based therapy. However, additional controlled studies are needed.

Free access

Albert P. Wong, Rishi R. Lall, Nader S. Dahdaleh, Cort D. Lawton, Zachary A. Smith, Ricky H. Wong, Michael J. Harvey, Sandi Lam, Tyler R. Koski, and Richard G. Fessler

OBJECT

Patients with symptomatic intradural-extramedullary (ID-EM) tumors may be successfully treated with resection of the lesion and decompression of associated neural structures. Studies of patients undergoing open resection of these tumors have reported high rates of gross-total resection (GTR) with minimal long-term neurological deficit. Case reports and small case series have suggested that these patients may be successfully treated with minimally invasive surgery (MIS). These studies have been limited by small patient populations. Moreover, there are no studies directly comparing perioperative outcomes between patients treated with open resection and MIS. The objective of this study was to compare perioperative outcomes in patients with ID-EM tumors treated using open resection or MIS.

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A retrospective review was performed using data collected from 45 consecutive patients treated by open resection or MIS for ID-EM spine tumors. These patients were treated over a 9-year period between April 2003 and October 2012 at Northwestern University and the University of Chicago. Statistical analysis was performed to compare perioperative outcomes between the two groups.

RESULTS

Of the 45 patients in the study, 27 were treated with the MIS approach and 18 were treated with the open approach. Operative time was similar between the two groups: 256.3 minutes in the MIS group versus 241.1 minutes in the open group (p = 0.55). Estimated blood loss was significantly lower in the MIS group (133.7 ml) compared with the open group (558.8 ml) (p < 0.01). A GTR was achieved in 94.4% of the open cases and 92.6% of the MIS cases (p = 0.81).

The mean hospital stay was significantly shorter in the MIS group (3.9 days) compared with the open group (6.1 days) (p < 0.01). There was no significant difference between the complication rates (p = 0.32) and reoperation rates (p = 0.33) between the two groups. Multivariate analysis demonstrated an increased rate of complications in cervical spine tumors (OR 15, p = 0.05).

CONCLUSIONS

Thoracolumbar ID-EM tumors may be safely and effectively treated with either the open approach or an MIS approach, with an equivalent rate of GTR, perioperative complication rate, and operative time. Patients treated with an MIS approach may benefit from a decrease in operative blood loss and shorter hospital stays.

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Aaron Hockley, Michael K. Tso, Mohammed A. Almekhlafi, Abhay K. Lodha, Robin Clegg, Jeremy Luntley, Muneer Eesa, and John H. Wong

OBJECTIVE

Vein of Galen aneurysmal malformations (VGAMs) in infancy have a poor natural history if left untreated. Their high-flow nature can preclude safe and accurate therapeutic vessel occlusion and the risk of inadvertent pulmonary embolism is predominant. The authors describe the technique of rapid cardiac ventricular pacing for inducing transient hypotension to facilitate the controlled embolization of VGAMs.

开云体育世界杯赔率

Initial transjugular venous access was obtained for placing temporary pacing leads for rapid cardiac ventricular pacing immediately prior to embolization. Definitive transarterial embolization procedures for the VGAMs were then performed in the same setting in which liquid embolic agents or coils were used.

RESULTS

Beginning in 2010, a total of five procedures were performed in three infants. Transvenous rapid cardiac ventricular pacing was successfully achieved to induce systemic transient flow arrest in all but two attempts, and facilitated partial embolization with n-butyl cyanoacrylate (n-BCA) and coils in all procedures. Ventricular fibrillation occurred twice in one patient and was successfully reversed with defibrillation on both occasions. One patient failed to improve and died from refractory heart failure. Two patients stabilized following staged embolization.

CONCLUSIONS

Rapid transvenous cardiac ventricular pacing can be considered to induce transient hypotension and facilitate controlled embolization in challenging high-flow VGAMs.

Restricted access

Mansoor Foroughi, Andrew Wong, Paul Steinbok, Ash Singhal, Michael A. Sargent, and D. Douglas Cochrane

Object

The criteria for identifying patients in whom endoscopic third ventriculostomy (ETV) provides control of hydrocephalus remain in evolution. In particular, it is not clear when ETV would be effective if intraventricular obstruction is not found preoperatively. The authors postulated that 1) displacement of the third ventricle floor inferiorly into the interpeduncular cistern and displacement of the lamina terminalis anteriorly into the lamina terminalis cistern could predict clinical success of ETV, and 2) improvement in these displacements would correlate with the success of ETV.

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Magnetic resonance imaging in 38 consecutive patients treated between 2004 and 2010 was reviewed to assess displacement of the lamina terminalis and third ventricular floor prior to and following ETV. Displacements of the floor and lamina terminalis were judged qualitatively and quantitatively, using a newly created index, the Third Ventricular Morphology Index (TVMI). The association between the aforementioned morphological features and clinical success of ETV was analyzed.

Results

Ninety-six percent of patients in whom the authors preoperatively observed displacement of the lamina terminalis and the third ventricular floor were successfully treated with ETV. Displacements of the third ventricular floor and lamina terminalis, as judged qualitatively, correlated with the clinical success of ETV. The TVMI correlated with the qualitative assessments of displacement. Postoperative decrease in the TVMI occurred in the majority of successfully treated patients. Changes in third ventricular morphology preceded changes in other measures of third and lateral ventricular volume following ETV.

Conclusions

Assessment of third ventricular floor and lamina terminalis morphology is useful in predicting clinical success of ETV and in the follow-up in treated patients. The TVMI provided a quantitative assessment of the third ventricular morphology, which may be useful in equivocal cases and in research studies.

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Michael B. Avery, Ahmed Alaqeel, Amy B. Bromley, Yong-Xiang Chen, John H. Wong, Muneer Eesa, and Alim P. Mitha

OBJECTIVE

Reliable animal models are an important aspect of translational research, especially for relatively uncommon clinical entities such as fusiform aneurysms. While several animal models exist, very few are tailored to cerebral fusiform aneurysms, which have unique attributes compared to abdominal fusiform aneurysms. The authors aimed to build from previous models to create a cerebral fusiform aneurysm model that is simple to use and reliable.

开云体育世界杯赔率

Twelve female New Zealand White rabbits were assigned to 3 groups: group E, elastase only; group C, CaCl2only; group EC, elastase + CaCl2. All rabbits underwent surgical exposure of the right common carotid artery (CCA) and 20 minutes of peri-carotid incubation with their respective chemicals. Angiography was performed 6 weeks later for arterial dilation measurements, with 50% increase in diameter being defined as fusiform aneurysm formation. The arterial segments, along with the contralateral CCAs, were harvested and assessed histologically for wall component measurements and elastin semiquantification. A separate rabbit underwent aneurysm creation per the group EC protocol and was treated with an endovascular flow-diversion device.

RESULTS

All of the group EC rabbits developed fusiform aneurysms (mean dilation of 88%), while none of the group E or group C rabbits developed aneurysms (p = 0.001). Histological analysis revealed increased internal elastic lamina fragmentation in the group EC aneurysms, which also had less tunica intima hyperplasia. All aneurysms exhibited thinning of the tunica media and reduction in elastin content. The use of an endovascular flow-diverting stent was successful, with complete parent vessel remodeling, as expected, 4 weeks after deployment.

CONCLUSIONS

The peri-arterial application of combined elastase and CaCl2to the CCA appears sufficient to reliably produce fusiform aneurysms after 6 weeks. Exposure to elastase or CaCl2individually appears insufficient, despite the observed histological changes to the arterial wall. The proposed fusiform aneurysm model is able to accommodate endovascular devices, simulating the tortuous pathway experienced in using such devices in human cerebral aneurysms and thus is a satisfactory model to use in translational research.

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Michael K. Tso, Myunghyun M. Lee, Chad G. Ball, William F. Morrish, Alim P. Mitha, Andrew W. Kirkpatrick, and John H. Wong

OBJECTIVE

Blunt cerebrovascular injury (BCVI) occurs in approximately 1% of the blunt trauma population and may lead to stroke and death. Early vascular imaging in asymptomatic patients at high risk of having BCVI may lead to earlier diagnosis and possible stroke prevention. The objective of this study was to determine if the implementation of a formalized asymptomatic BCVI screening protocol with CT angiography (CTA) would lead to improved BCVI detection and stroke prevention.

开云体育世界杯赔率

Patients with vascular imaging studies were identified from a prospective trauma registry at a single Level 1 trauma center between 2002 and 2008. Detection of BCVI and stroke rates were compared during the 3-year periods before and after implementation of a consensus-based asymptomatic BCVI screening protocol using CTA in 2005.

RESULTS

A total of 5480 patients with trauma were identified. The overall BCVI detection rate remained unchanged postprotocol compared with preprotocol (0.8% [24 of 3049 patients] vs 0.9% [23 of 2431 patients]; p = 0.53). However, postprotocol there was a trend toward a decreased risk of stroke secondary to BCVI on a trauma population basis (0.23% [7 of 3049 patients] vs 0.53% [13 of 2431 patients]; p = 0.06). Overall, 75% (35 of 47) of patients with BCVI were treated with antiplatelet agents, but no patient developed new or progressive intracranial hemorrhage despite 70% of these patients having concomitant traumatic brain injury.

CONCLUSIONS

The results of this study suggest that a CTA screening protocol for BCVI may be of clinical benefit with possible reduction in ischemic complications. The treatment of BCVI with antiplatelet agents appears to be safe.

Free access

雪莱x扁,大卫•Routman乔纳森刘, Dongyun Yang, Susan Groshen, Gabriel Zada, Nicholas Trakul, Michael K. Wong, Cheng Yu, and Eric L. Chang

OBJECTIVE

Stereotactic radiosurgery (SRS) is routinely used to treat brain metastases from melanoma due to their radioresistant nature. The median survival for these patients is 4–6 months, according to earlier studies. The aim of this study was to evaluate prognostic factors that influence survival in patients with metastatic melanoma to the brain treated with SRS.

开云体育世界杯赔率

This retrospective analysis included all patients with melanoma brain metastases treated with SRS at the University of Southern California between 1994 and 2015. For the entire cohort, the authors performed a multivariable Cox regression analysis with an end point of survival. Covariates included number of lesions, total intracranial tumor volume, age, sex, and treatment date prior to 2005 or 2005 onward.

In the subset of patients with > 1 lesion, additional multivariable Cox regression was performed, with covariates of Karnofsky Performance Scale, Graded Prognostic Assessment, Recursive Partitioning Analysis, timing of metastases (synchronous/metachronous), change in lesion number, and previous whole-brain radiation therapy or resection in addition to the previously mentioned covariates. Overall survival (OS) was calculated from the day SRS was performed to the date of last follow-up or date of death.

RESULTS

A total of 401 patients were available for analysis. The median follow-up was 35.1 months for patients alive at the time of analysis, and the median OS was 7.7 months for the entire cohort (95% CI 6.7–8.3 months). In the entire cohort, greater number of brain lesions, higher total intracranial tumor volume, age > 50 years, treatment prior to 2005, and male sex were found to be statistically significant factors associated with worse survival. The strongest risk factors for decreased OS were tumor volume > 10 cm3and ≥ 5 lesions, with hazard ratios for risk of death of 1.7 and 2.2, respectively. In the subset of patients with > 1 lesion, tumor volume > 10 cm3and no resection were the only factors significantly associated with decreased OS, with hazard ratios of 1.9 and 2.0 (hazard ratio of 0.49 for resection), respectively.

CONCLUSIONS

这项研究表明,更大的病变数量,嗨gher intracranial tumor volume, older age, treatment prior to 2005, and male sex have prognostic significance for decreased OS in patients with melanoma brain metastases treated with SRS. Additionally, in the subset of patients with > 1 lesion, only higher total tumor volume and no resection were associated with worse survival.

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