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关键词： Balloon occlusion   Carotid-cavernous sinus fistula   Embolization  

摘要： BACKGROUND: As previous studies reported, the ballon guide catheter is useful for identifying the fistula point during diagnosis of direct carotid-cavernous sinus fistula (d-CCF). We demonstrate an additional advantage of the balloon guide catheter during intraarterial endovascular treatment of d-CCF. METHODS: Two cases of d-CCF are presented in this -port. A balloon guide catheter is used to help achieve successful coil embolization of the fistula in both cases. RESULTS: Microcatheter positioning into the fistulous point can be easier after balloon inflation. Balloon inflation can help with coil deployment. CONCLUSIONS: Using a balloon guiding catheter can reduce internal carotid artery flow near the fistula point at the cavernous segment of the internal carotid artery. As a result, better identification of the fistula point can be made, which allows easier placement of the microcatheter into the fistula point and more stable coil deployment.

关键词： Cerebral palsy   Spasticity   Dystonia   Baclofen pump   Baclofen   Movement disorders  

摘要： Purpose This study aims to describe a new baclofen pump implantation technique with pre-brainstem catheter placement and to demonstrate the benefits that this procedure has in treating spasticity and dystonia. Methods We described a new technique to place a baclofen pump catheter anterior to the brainstem. To illustrate the technique, we presented five patients with both spasticity and dystonia in whom conventional treatment was not effective. They each received a baclofen pump with a pre-brainstem catheter. We evaluated the results using the Ashworth scale for spasticity, the Barry-Albright scale for dystonia, and the PedsQL for quality of life assessment. Each patient was evaluated before a surgery and after 6 months of follow-up. Results There were statistically significant differences in all the physical examination evaluated areas using the Barry-Albright and modified Ashworth scales between the preoperative and the postoperative period. The same applies to the results of the PedsQL quality of life scale. Conclusion We presented an innovative baclofen pump implantation technique with pre-brainstem catheter placement that could be a therapeutic alternative in patients with dystonia and spastic quadriparesis for whom conventional therapy is not effective.

关键词： Longitudinal train dynamics   pneumatic braking   in-train forces   longitudinal compressive forces   long trains   multibody simulation  

摘要： Long freight trains up to 1500 m in length are currently not in regular operation in Europe. One of the important reasons for the same is high inter-wagon forces generated during the operation, especially when pneumatic (P-type) brake systems are used. For long trains with multiple locomotives at different positions along the train, radio communication with necessary fail-safe mechanisms can be used to apply the brakes. Long freight train operation on a given line is subjected to various attributes such as braking/traction scenarios, loading patterns, wagon geometries, brake-block materials, buffer types, track design geometries, etc., which are referred to as heterogeneities. The complex longitudinal train dynamics arising in the train due to various heterogeneities play a major role in determining its running safety. In this context, the maximum in-train force refers to the maximum force developed between any two wagons along the train during operation. The tolerable longitudinal compressive force is the maximum compressive force that can be exerted on a wagon without resulting in its derailment. Here, the authors adopt a bottom-up approach to model pneumatic braking systems and inter-wagon interactions in multibody simulation environments to study the complex longitudinal train dynamics behavior and estimate maximum in-train forces and tolerable longitudinal compressive forces, subjected to various heterogeneities. These two force quantities intend to facilitate a given freight train operation by providing guidelines regarding the critical heterogeneities, that currently limit its safe operation. In doing so, the authors propose the notion to have an operation-based approval for long freight trains using the simulations-based tool.

关键词： Lamina terminalis   Tegmental   Midbrain   Surgical resection   Multimodal protocol  

摘要： Surgical resection of lesions located in the ventral midbrain is challenging. Few approaches and safe entry zones (SEZs) have been proposed and used to remove this type of lesion, and each has its limitations. Using two illustrating cases, the authors describe a trans-lamina terminalis suprategmental approach for removing ventral midbrain lesions. This approach provides a straight surgical trajectory with sparse neurovascular structures and can be performed with a standard pterional or subfrontal craniotomy. It may be the ideal approach for ventromedial midbrain lesions extending towards the third ventricle. (C) 2020 Elsevier Ltd. All rights reserved.

ISBN: (纸本)9787506872782

关键词： Genioplasty   Mandibular Nerve   Computer-aided design   Printing   Three-dimensional   Operative Time   Rejuvenation  

关键词： Awake craniotomy   Brain mapping   Intraoperative electrical stimulation   Epilepsy   Music   Cavernoma  

摘要： The aim of this manuscript is to present our intraoperative technique assessing the ability to perform music. Our protocol excludes cases where performance can be disrupted by motor deficits. The positive cortical sites (the posterior part of the superior temporal gyrus and supramarginal gyrus) related purely music performance are also reported. We present the case of a patient, an amateur piano player who underwent surgery for a symptomatic supratentorial cavernoma while awake with intraoperative brain mapping. This case report shows that amateur and possibly professional musicians may benefit from awake procedures. This report confirms that stimulation of the specific area of the brain can disturb the function of a large network responsible for high-level cognitive task, like music performance. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： dose calculation for radiotherapy   magnetic resonance imaging   proton therapy   quantitative imaging  

摘要： Purpose Proton therapy is becoming an increasingly popular cancer treatment modality due to the proton's physical advantage in that it deposits the majority of its energy at the distal end of its track where the tumor is located. The proton range in a material is determined from the stopping power ratio (SPR) of the material. However, SPR is typically estimated based on a computed tomography (CT) scan which can lead to range estimation errors due to the difference in x-ray and proton interactions in matter, which can preclude the ability to utilize protons to their full potential. Applications of magnetic resonance imaging (MRI) in radiotherapy have increased over the past decade and using MRI to calculate SPR directly could provide numerous advantages. The purpose of this study was to develop a practical implementation of a novel multimodal imaging method for estimating SPR and compare the results of this method to physical measurements in which values were computed directly using tissue substitute materials fabricated to mimic skin, muscle, adipose, and spongiosa bone. Methods For both the multimodal imaging method and physical measurements, SPR was calculated using the Bethe-Bloch equation from values of relative electron density and mean ionization potential determined for each tissue. Parameters used to estimate SPR using the multimodal imaging method were extracted from Dixon water-only and (H-1) proton density-weighted zero echo time MRI sequences and CT, with both kVCT and MVCT used separately to evaluate the performance of each. For comparison, SPR was also computed from kVCT using the stoichiometric method, the current clinical standard. Results Results showed that our multimodal imaging approach using MRI with either kVCT or MVCT was in close agreement to SPR calculated from physical measurements for the four tissue substitutes evaluated. Using MRI and MVCT, SPR values estimated using our method were within 1% of physical measurements and were more accura

关键词： EPID   IMRT   markerless spine tracking   treatment beam imaging  

摘要： Purpose One of the biggest challenges in applying megavoltage (MV) treatment beam imaging for monitoring spine motion in stereotactic body radiotherapy (SBRT) is the small beam apertures in the images due to strong beam modulations in IMRT planning. The purpose of this study is to investigate the feasibility of a markerless motion tracking method in spine SBRT delivery using a novel enhanced synthetic treatment beam (ESTB) imaging technique. Methods Three clinical spine SBRT plans using 6XFFF beams and sliding window IMRT technique were transferred to a thorax phantom and delivered by a TrueBeam machine. Before delivery, the phantom was aligned to the plan isocenter using CBCT setup and verified with a second CBCT, and then, 2 mm shifts were introduced in both the craniocaudal (CC) and the left-right (LR) directions with the couch. During beam delivery, MV images were continuously taken with an electronic portal imaging device (EPID) and automatically grabbed by Varian iTools Capture software with a frame rate of 11.6 Hz. After preprocessing for scatter correction and beam intensity compensation, every 50 frames of MV images were combined to generate a series of ESTB images for each beam. The ESTB images were then registered to the projections of the verification CBCT at the matched beam angles to detect the 2 mm shifts. Results Compared to snapshot MV images, the ESTB images had significantly enlarged fields of view (FOVs) and improved image quality. Based on two-dimensional (2D) rigid registration, the ESTB image to CBCT projection matching showed submillimeter accuracy in detecting motion. Specifically, the root mean square errors in detecting the LR/CC shifts were 0.35/0.28, 0.32/0.35, 0.63/0.44, 0.55/0.51, and 0.69/0.42 mm at gantry angles 180, 160, 140, 120, and 100, respectively. Conclusion Our results in the phantom study suggest that ESTB images from a sliding window IMRT plan can be used to detect spine motion, with submillimeter precision in the 2D plane