Search

Purpose: Magnetic resonance imaging (MRI) is the current standard for preoperative planning of glioblastoma (GBM) surgery. However, recent data on the use of 11C-methionine positron emission tomography (11[C]-MET PET) suggest its role in providing additional information beyond MRI. The purpose of this study is to establish if there is a correlation between anatomical and metabolic data. Methods: We retrieved all GBM cases treated at our institution from 2014 to January 2021. Preoperative MRI (Enhancing Nodule -EN-, FLAIR and Total Tumor Volume -TTV-) and PET volumes were evaluated to analyze potential correlations between anatomical and metabolic data. These findings were then correlated with pathological results obtained from the different radiological tumor regions. Results: 150 patients underwent surgery for GBM and 49 of these were also studied preoperatively with 11[C]-MET PET; PET volume was evaluated in 47 patients. In 33 patients (70.21%) preoperative 11[C]-MET PET volume > preoperative EN volume and in 11 (23.4%) preoperative 11[C]-MET PET volume > preoperative TTV. We found a significant correlation between preoperative TTVs and PET volumes (p = 0.016) as well as between preoperative EN volumes and PET volumes (p = Conclusion: In our series PET volumes correlated with EN and TTV on preoperative MRI, indicating that PET should be considered in the presurgical planning to achieve a supratotal resection.

It is generally accepted that Glioblastoma (GBM) arise from cancer stem cells (CSC), however, there is little evidence on their anatomical distribution. We investigated the expression and distribution of SOX-2-positive and CD133-positive CSCs both in the enhancing nodule (EN) of GBM and in the FLAIR hyperintensity zones on a surgical, histopathological series of 33 GBMs.The inclusion criterion was the intraoperative sampling of different tumor regions individualized thanks to Neuronavigation and positivity to intraoperative fluorescence with the use of 5-aminolevulinic acid (5-ALA). 33 patients (20 males and 13 females with a mean age at diagnosis of 56 years) met the inclusion criterion. A total of 109 histological samples were evaluated, 52 for ENs and 57 for FLAIR hyperintensity zone. Considering the quantitative distribution of levels of intensity of staining (IS), ES (extent score) and immunoreactivity score (IRS), no difference was found between ENs and FLAIR regions for both the SOX-2 biomarker (respectively, IS p=0.851, ES p=0.561, IRS p=1.000) and the CD133 biomarker (IS p=0.653, ES p=0.409, IRS p=0.881). This evidence suggests to recalibrate the target of surgery for FLAIRECTOMY and 5-ALA could improve the possibility to achieve this goal.

Ping-pong fractures have become less frequent, and no definite predictors to determine which fractures will elevate spontaneously and which should undergo surgical treatment have been clearly defined. Herein, the authors present a revision of the literature, in which 54 papers were included, with a total of 228 children studied. Patients who underwent surgery accounted for 30%; elevation through obstetrical vacuum or other aspiration systems was applied in 30%; and spontaneous resolution occurred in 40%; in 4 patients, percutaneous microscrew elevation was applied. Overall, in 96.4% of patients, the outcome was favorable because we found no significant increase in the incidence of post-traumatic seizures or neurologic sequelae with no significant differences between treated patients and spontaneous elevation. Statistical analysis showed no significant differences among the different treatment methods (P = 0.53). Our results suggest that simple compound ping-pong fractures without brain compression, hematomas, or dural tears could benefit from conservative management. In cases of nonspontaneous resolution after 6 months, operative strategies should be performed, considering that there is no evidence of differences between vacuum elevation and surgical elevation.

OBJECTIVENo consensus exists on the best treatment for recurrent high-grade glioma (HGG), particularly in terms of surgical indications, and scant data are available on the integrated use of multiple technologies to overcome intraoperative limits and pitfalls related to artifacts secondary to previous surgery and radiotherapy. Here, the authors report on their experience with the integration of multiple intraoperative tools in recurrent HGG surgery, analyzing their pros and cons as well as their effectiveness in increasing the extent of tumor resection. In addition, they present a review of the relevant literature on this topic.METHODSThe authors reviewed all cases in which recurrent HGG had been histologically diagnosed after a first surgery and the patient had undergone a second surgery involving neuronavigation with MRI, intraoperative CT (iCT), 11C-methionine–positron emission tomography (11C-MET-PET), 5-aminolevulinic acid (5-ALA) fluorescence, intraoperative neurophysiological monitoring (IONM), and intraoperative navigated ultrasound (iUS). All cases were classified according to tumor functional grade (1, noneloquent area; 2, near an eloquent area; 3, eloquent area).RESULTSTwenty patients with recurrent HGG were operated on using a multimodal protocol. The recurrent tumor functional grade was 1 in 4 patients, 2 in 8 patients, and 3 in the remaining 8 patients. In all patients but 2, 100% EOTR was obtained. Intraoperative 5-ALA fluorescence and navigated iUS showed low specificity and sensitivity. iCT detected tumor remnants in 3 cases. Postoperatively, 6 patients (30%) had worsening neurological conditions: 4 recovered within 90 days, 1 partially recovered, and 1 experienced a permanent deficit. The median Karnofsky Performance Status remained substantially unchanged over the follow-up period. The mean progression-free survival after the second surgery was 7.7 months (range 2–11 months). The mean overall survival was 25.4 months (range 10–52 months), excluding 2 long survivors. Two patients died within 60 days after surgery, and 3 patients were still under follow-up at the end of this study.CONCLUSIONSThis is the first study reporting the integration of neuronavigation, 5-ALA fluorescence, iUS, iCT, 11C-MET-PET, and IOM during microsurgical resection of recurrent glioma. The authors believe that the proposed multimodal protocol is useful to increase the safety, effectiveness, and EOTR in patients with recurrent HGG and brain alterations secondary to radio- and chemotherapy.

The evaluation of the road surface roughness condition plays an important role for the assessment of the pavement condition. To measure the international roughness index (IRI), new emerging surveying techniques can be used in addition to the profilometer. Mobile laser scanner (MLS) data were acquired on a stretch of road and interpolated on a grid to build a 3D model representing the whole road surface. To evaluate the roughness, both dynamic and geometric IRIs were computed from (digital elevation model) DEM-derived elevation attributes. The computed values showed a similar trend and a high correlation with that derived from the profilometer; the differences between the corresponding values were generally less than 5%. To evaluate the effects of vibrations on human comfort, the built DEM was integrated into a dynamic simulation software user interface to compute the effects on the drivers of the vertical accelerations, considered another indicator of the pavement performance.

The assessment of the road roughness conditions plays an important role to ensure the required performances related to road safety and ride comfort, furthermore providing a tool for pavement maintenance and rehabilitation planning. In this work, the authors compared the roughness index (International Roughness Index, IRI) derived from high speed inertial profilometer with two other roughness indices, one dynamic and one geometric computed on a digital elevation model (DEM) built by using mobile laser scanner (MLS) data. The MLS data were acquired on an extra-urban road section and interpolated on the nodes of a DEM with a curvilinear abscissa, coinciding with the global navigation satellite system (GNSS) track of the profilometer. To estimate the grid cell elevation, we applied two interpolation methods, ordinary kriging (OK) and inverse distance weighting (IDW), over the same data. The roughness values computed on the surface of the DEM showed a similar trend and a high correlation with those acquired by the profilometer, higher for the dynamic index than for the geometric index. The differences between the IRI values by profilometer and those computed on the DEM were small enough not to significantly affect the judgments on the analyzed sections. Moreover, the road sub-sections derived from profilometer measure that were classified as critical coincided with those derived from light detection and ranging (LiDAR) surveys. The proposed method can be used to perform a network-level analysis. In addition, to evaluate the effects of vibrations on human comfort, we input the DEMs into a dynamic simulation software in order to compute the vertical accelerations, as specified in the UNI ISO 2631 standard. The values obtained were in line and correlated with those inferred from the standard methodology for profilometer measures.

The monitoring of pavement distress takes a key role with respect to the functionality of a road structure, which is necessary to schedule maintenance works, optimizing the available resources. The identification, classification and quantification of different typology of distress involve complex practical activities and data processing that are sometimes inefficient and risky since interfere with road traffic. Our work focuses on the three-dimensional reconstruction of the paved surface making use of innovative technologies of surveying and data computation for the purpose of vehicle dynamics simulation. With the evolving LiDAR (Light Detection and Ranging) technologies, including static and mobile laser scanners, it is possible to obtain very dense point clouds. The experimentation concerns a road segment whose surface has been surveyed by means of a static Terrestrial Laser Scanner (TLS) and a Mobile Laser System (MLS) to analyze their performances and compare the results in a test case. These data were used to generate a few 3D geometrical models of the road surface. The IRI (International roughness Index) was computed on both the TLS and MLS surface, this latter measured at different acquisition speed. In order to evaluate road safety and comfort, the DEM (Digital Elevation Model) was imported in a vehicle dynamics simulation software that predicts the performance of vehicles in response to driver’s controls.

Objective Chronic subdural hematoma (CSH) is a common neurosurgical disease among elderly population with concomitant degenerative neurological disorders. This is a retrospective series-control analysis of prospectively collected data, aiming to show advantages and indications of a minimally invasive, percutaneous drainage system for CSH. Patients and methods We retrospectively analyse the clinical and radiological data of a minimally invasive, percutaneous draining system (Integra ™) used in fifteen patients (Group A; mean age: 75.7) with CSH, and compare them with those obtained from two retrospective series of patients: the first one (Group B 15 patients, mean age 77.1) treated with standard, single-burr hole technique for subdural drainage under general anaesthesia; the second one (Group C 15 patients, mean age 76.4) treated with standard, single-burr hole technique for subdural drainage under local anaesthesia and mild sedation. All The percutaneous procedures (Group A) were performed under local anaesthesia. Results Mean follow-up was 10.9 (range 3–14), 18.2 (range 10–29) and 15.2 (range 8–28) months in Group A, B and C respectively. Three of 15 and in Group B experienced a worsening of pre-existing neurodegenerative disorders after general anaesthesia. One patient in group C suffering from Parkinson’s disease experienced a worsening of gait disturbances. Post-operative CT scans were performed at 48 h and 21 days after the operation. An early post-operative CT-scan, obtained immediately after surgical procedure, was performed in all Group A patients. No differences in CSH evacuation were observed comparing the three groups. Two recurrent hematomas, one in group A and one in group B, required revision. Post-operative hospitalization was similar (5.1 vs 5.7 vs 5.6 days, respectively, in group A, B and C) but analgesics use was lower in Group A. Conclusion Pre-operative evaluation of radiological features of CSDHs is crucial in determining the right indication for a minimally invasive drainage. Minimally invasive treatments of CSH may reduce the use of anaesthetic drugs and worsening of pre-existing neurodegenerative disorders.

An increasing number of Intelligent Transportation System (ITS) applications require high accurate vehicle positioning, e.g., positioning at the lane-level. This requirement motives the development of modeling the road network at the lane-level. In this paper we propose a novel lane-level road network model. It can be considered an improvement to existing models in its capability of representing the road and intersection details at the lane-level in a uniform and precise way. As a result, the model can guarantee the global continuity for arbitrary map route, which better approximates the real vehicle trajectory. In addition, the map construction algorithms are also developed. Following the proposed methods, the lane parameters can be extracted efficiently under flexible precision requirement, and intersections with varying appearances can be precisely modeled with limited extra data. Experiments were performed to verify the proposed model in representing the lane-level geometrical and topological details of an urban area of Milan. The results also demonstrate the effectiveness of the map construction methods.

The inspection and maintenance of bridge decks is a procedure that requires objectivity and systematic steps; great benefits would derive from the adoption of automated techniques minimizing the human intervention. From this point of view, the laser scanner technology can provide excellent results; in order to reconstruct the geometry of the underbridge, the scanning head can be mounted on a motorized cart travelling on a walkway moved by a truck. The motion of the laser scanning head must be compensated in post-processing in order to obtain a reliable reconstruction of the underbridge geometry; the accuracy of the reconstruction depends on the accuracy of the trajectory itself. This paper describes the actions undertaken to improve a measurement system based on noncontact techniques (laser distance meters and vision systems) aimed to reconstruct the scanning head trajectory with respect to a reference system integral to the bridge deck. The measurement uncertainty of the proposed system was evaluated by numerical simulations and then experimentally verified. At first, the developed mathematical model was validated through a comparison with an ideal system simulated in SimMechanics. Experiments performed in a controlled environment proved the validity of the proposed approach.

This paper presents a method for measuring the non-controlled trajectory of a cart along a bounded rectilinear path. The method uses non-contact measurement devices to identify the position of a movable laser scanner working in helical mode in order to reconstruct the 3D model of bridges. The main idea of the proposed method is to use vision systems in order to identify the coordinates of the laser scanner placed on the cart with respect to the global reference system. A fit-to-purpose vision system has been implemented: the system uses three CCD's cameras mounted on the cart to identify the relative rotations with respect to the environment. Two lasers pointers and a laser distance meter are fixed at the starting point of the trajectory and pointing in the direction of motion of the cart, creating three dots on a plane placed on the cart. One of the camera detects the cart displacements and rotations in the plane using a blob analysis procedure. The method described in this paper has a constant uncertainty and the measurement range only depends on the lasers power. The theoretical accuracy of the measurement system is close to 1 mm for the translation along the motion direction and around 0.5 mm along the other two directions. Orientations measurement have a theoretical accuracy of less than 0.1 °. The solution has been implemented for the 3D reconstruction of concrete bridge; preliminary experimental results are presented and discussed.

Concrete bridge inspection is nowadays primarily a slow, subjective, non-comprehensive and costly set of procedures. Automation of the acquisition method is especially desirable for economical and repeatability reasons. Digital data is normally derived from well established non-destructive testing techniques, high resolution cameras and, more recently, by 3D laser scanning. This latter technique has some advantageous aspects in terms of reliability, repeatability, completeness and intuitiveness of the analysis of the resulting 3D reconstruction of the concrete structure. Statical laser scanning is, though, impractical for a variety of different reasons. A possible way of overcoming such difficulties is represented by dynamical measurement, achieved by moving in a prescribed manner the laser scanner during the scanning process. This procedure, on the other hand, requires a reliable tracking system for the laser scanner position and orientation. This work focuses on the development of such system, based primarily on computer vision measurement systems. A compact and lightweight 3D laser scanner has been placed on an automated carrier able to move along a standard inspection by-bridge, and a system of cameras and transducers has been designed to measure the carrier position and orientation based on the assumption of rigid body motion of the by-bridge multi-link arm during inspection operations. Several experimental tests have been performed to assess the viability of the proposed system and to evaluate its performance.Copyright © 2014 by ASME