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Sample records for neuronavigation

  1. Neuronavigation. Principles. Surgical technique.

    PubMed

    Ivanov, Marcel; Ciurea, Alexandru Vlad

    2009-01-01

    Neuronavigation and stereotaxy are techniques designed to help neurosurgeons precisely localize different intracerebral pathological processes by using a set of preoperative images (CT, MRI, fMRI, PET, SPECT etc.). The development of computer assisted surgery was possible only after a significant technological progress, especially in the area of informatics and imagistics. The main indications of neuronavigation are represented by the targeting of small and deep intracerebral lesions and choosing the best way to treat them, in order to preserve the neurological function. Stereotaxis also allows lesioning or stimulation of basal ganglia for the treatment of movement disorders. These techniques can bring an important amount of confort both to the patient and to the neurosurgeon. Neuronavigation was introduced in Romania around 2003, in four neurosurgical centers. We present our five-years experience in neuronavigation and describe the main principles and surgical techniques. PMID:20108488

  2. Intraventricular trigonal meningioma: Neuronavigation? No, thanks!

    PubMed Central

    Silva, Danilo O. A.; Matis, Georgios K.; Costa, Leonardo F.; Kitamura, Matheus A. P.; Birbilis, Theodossios A.; Azevedo Filho, Hildo R. C.

    2011-01-01

    Background: Most of the time meningiomas are benign brain tumors and surgical removal ensures cure in the vast majority of the cases. Thus, whenever possible, complete surgical resection should be the goal of the treatment. Methods: This is a report of our surgical technique for the operative resection of a trigonal meningioma in a resource-limited setting. The necessity of accurate and deep knowledge of the regional anatomy is outlined. Results: A 44-year-old male presented to our outpatient clinic complaining of cephalalgia increasing in frequency and intensity over the last month. His neurological exam was normal, yet a brain computed tomography scan revealed a lesion in the right trigone of the ventricular system. The diagnosis of possible meningioma was set. After thoroughly informing the patient, tumor resection was decided. An intraparietal sulcus approach was favored without the use of any modern technological aids such as intraoperative magnetic resonance imaging or neuronavigation. The postoperative course was uneventful and a postoperative computed tomography scan demonstrated the complete resection of the tumor. The patient was discharged two days later with no neurological deficits. In a two-year-follow-up he remains recurrence-free. Conclusion: In the current cost-effective era it is still possible to safely remove an intraventricular trigonal meningioma without the convenience of neuronavigation. Since the best neuronavigator is the profound neuroanatomical knowledge, no technological advancement could replace a well-educated and trained neurosurgeon. PMID:21886886

  3. Neuronavigation as a diagnostic tool: An innovative application.

    PubMed

    Anderson, Ian A; Chumas, Paul D

    2016-06-01

    The role of neuronavigation in tumour surgery is well established. We present an innovative use for this software, as a tool to compare ventricular size between serial sets of cranial imaging. We conclude that neuronavigation software is potentially a powerful diagnostic tool that should not be overlooked when making comparative assessments between scans. PMID:26742421

  4. [Application of frameless neuronavigation in urgent neurosurgery].

    PubMed

    Krylov, V V; Burov, S A; Dash'ian, V G; Shaklunov, A A

    2008-01-01

    Application of a novel technique is analyzed. Frameless CT-based navigation was applied for planning of surgical approach in 92 patients aged 14 to 69 with acute intracranial hemorrhage of different etiology (43 cases of hypertensive hemorrhages, 10 cases of traumatic intracranial hematomas and 16 cases of secondary non-traumatic intracerebral hematomas). Comparative analysis of radioopaque markers and natural anatomical landmarks for registration of patients showed that anatomical landmarks are sufficient for surgical planning without significant distortion of approach trajectory (mean error was 2.2 +/- 1 mm) in supratentorial haemorrhage. This discovery simplified the application of neuronavigation in emergency cases. In posterior fossa hematomas additional radioopaque markers are essential due to absence of constant anatomical landmarks in occipital region. Applicatyion of frameless neuronavigation in surgical treatment of acute intracranial hemorrhages may diminish intraoperative damage to the brain tissue and decrease invasiveness of the operation because of high accuracy of planning of surgical approach. This technique has good perspectives in emergency neurosurgery. PMID:19062589

  5. Development of fluoroscopic registration in spinal neuronavigation

    NASA Astrophysics Data System (ADS)

    Abbasi, Hamid R.; Grzeszczuk, Robert; Chin, Shao; Holz, H.; Hariri, Sanaz; Badr, Rana; Kim, Daniel; Adler, John R.; Shahidi, Ramin

    2001-05-01

    We present a system involving a computer-instrumented fluoroscope for the purpose of 3D navigation and guidance using pre-operative diagnostic scans as a reference. The goal of the project is to devise a computer-assisted tool that will improve the accuracy, reduce risk, minimize the invasiveness, and shorten the time it takes to perform a variety of neurosurgical and orthopedic procedures of the spine. For this purpose we propose an apparatus that will track surgical tools and localize them with respect to the patient's 3D anatomy and pre-operative 3D diagnostic scans using intraoperative fluoroscopy for in situ registration and localization of embedded fiducials. Preliminary studies have found a fiducial registration error (FRE) of 1.41 mm and a Target Localization Error (TLE) of 0.48 mm. The resulting system leverages equipment already commonly available in the operating room (OR), providing an important new functionality that is free of many current limitations, such as the inadequacy of skin fiducials for spinal neuronavigation, while keeping costs contained.

  6. The Use of Neuronavigation as an Adjunct in Facial Reconstructive Surgery.

    PubMed

    Zhang, Zach Z; Peters, Daniel A; Allen, Murray; Boyd, Kirsty U

    2016-06-01

    Neuronavigation, a ubiquitous tool used in neurosurgery, is rarely used in maxillofacial reconstructive surgery despite it offering many advantages without any disadvantage to the patient. The present report describes one patient with complex gun-shot wound facial injury and one patient with a rare malignant peripheral nerve sheath tumor involving the skull base, in which neuronavigation was used to improve the accuracy of bony reduction and minimize surgical invasiveness. Although neuronavigation is not necessary for all maxillofacial surgery, it can be a useful adjunct in complex maxillofacial reconstruction and maxillofacial tumor resection. PMID:27228375

  7. Neuronavigation in the surgical management of brain tumors: current and future trends

    PubMed Central

    Orringer, Daniel A; Golby, Alexandra; Jolesz, Ferenc

    2013-01-01

    Neuronavigation has become an ubiquitous tool in the surgical management of brain tumors. This review describes the use and limitations of current neuronavigational systems for brain tumor biopsy and resection. Methods for integrating intraoperative imaging into neuronavigational datasets developed to address the diminishing accuracy of positional information that occurs over the course of brain tumor resection are discussed. In addition, the process of integration of functional MRI and tractography into navigational models is reviewed. Finally, emerging concepts and future challenges relating to the development and implementation of experimental imaging technologies in the navigational environment are explored. PMID:23116076

  8. Use of frameless neuronavigation for bedside placement of external ventricular catheters.

    PubMed

    Glenn, Chad A; Conner, Andrew K; Cheema, Ahmed A; Burks, Joshua D; Case, Justin L; O'Neal, Christen; Sughrue, Michael E

    2016-04-01

    Neuronavigation for placement of ventricular catheters has been described. At our institution, electromagnetic neuronavigation is frequently utilized for difficult ventricular catheter placement. In patients who develop a trapped ventricle as a result of an intraparenchymal or intraventricular mass lesion, successful catheter placement may be difficult, as the location and trajectory are unfamiliar. The authors report their experience using electromagnetic neuronavigation for bedside placement of external ventricular catheters in patients with trapped ventricles. The technique for bedside placement of external ventricular catheters utilizing electromagnetic neuronavigation is reviewed. The benefits of this technique and those patients in whom it may be most useful are discussed. Utilization of bedside electromagnetic neuronavigation for placement of difficult external ventricular catheters into trapped ventricles is an option for accurate navigated catheter placement. Bedside electromagnetic neuronavigation offers accurate catheter placement in awake patients. This technique may be utilized in patients with high perioperative risk factors as it does not require general anesthesia. The procedure is well tolerated as it does not require rigid head fixation. PMID:26642952

  9. Neuronavigation-guided Repetitive Transcranial Magnetic Stimulation for Aphasia.

    PubMed

    Kim, Woo-Jin; Hahn, Soo Jung; Kim, Won-Seok; Paik, Nam-Jong

    2016-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is widely used for several neurological conditions, as it has gained acknowledgement for its potential therapeutic effects. Brain excitability is non-invasively modulated by rTMS, and rTMS to the language areas has proved its potential effects on treatment of aphasia. In our protocol, we aim to artificially induce virtual aphasia in healthy subjects by inhibiting Brodmann area 44 and 45 using neuronavigational TMS (nTMS), and F3 of the International 10-20 EEG system for conventional TMS (cTMS). To measure the degree of aphasia, changes in reaction time to a picture naming task pre- and post-stimulation are measured and compare the delay in reaction time between nTMS and cTMS. Accuracy of the two TMS stimulation methods is compared by averaging the Talairach coordinates of the target and the actual stimulation. Consistency of stimulation is demonstrated by the error range from the target. The purpose of this study is to demonstrate use of nTMS and to describe the benefits and limitations of the nTMS compared to those of cTMS. PMID:27214154

  10. Integration of 3D intraoperative ultrasound for enhanced neuronavigation

    NASA Astrophysics Data System (ADS)

    Paulsen, Keith D.; Ji, Songbai; Hartov, Alex; Fan, Xiaoyao; Roberts, David W.

    2012-03-01

    True three-dimensional (3D) volumetric ultrasound (US) acquisitions stand to benefit intraoperative neuronavigation on multiple fronts. While traditional two-dimensional (2D) US and its tracked, hand-swept version have been recognized for many years to advantage significantly image-guided neurosurgery, especially when coregistered with preoperative MR scans, its unregulated and incomplete sampling of the surgical volume of interest have limited certain intraoperative uses of the information that are overcome through direct volume acquisition (i.e., through 2D scan-head transducer arrays). In this paper, we illustrate several of these advantages, including image-based intraoperative registration (and reregistration) and automated, volumetric displacement mapping for intraoperative image updating. These applications of 3D US are enabled by algorithmic advances in US image calibration, and volume rasterization and interpolation for multi-acquisition synthesis that will also be highlighted. We expect to demonstrate that coregistered 3D US is well worth incorporating into the standard neurosurgical navigational environment relative to traditional tracked, hand-swept 2D US.

  11. MRI Guided Brain Stimulation without the Use of a Neuronavigation System

    PubMed Central

    Vaghefi, Ehsan; Cai, Peng; Fang, Fang; Byblow, Winston D.; Stinear, Cathy M.; Thompson, Benjamin

    2015-01-01

    A key issue in the field of noninvasive brain stimulation (NIBS) is the accurate localization of scalp positions that correspond to targeted cortical areas. The current gold standard is to combine structural and functional brain imaging with a commercially available “neuronavigation” system. However, neuronavigation systems are not commonplace outside of specialized research environments. Here we describe a technique that allows for the use of participant-specific functional and structural MRI data to guide NIBS without a neuronavigation system. Surface mesh representations of the head were generated using Brain Voyager and vectors linking key anatomical landmarks were drawn on the mesh. Our technique was then used to calculate the precise distances on the scalp corresponding to these vectors. These calculations were verified using actual measurements of the head and the technique was used to identify a scalp position corresponding to a brain area localized using functional MRI. PMID:26413537

  12. Biomechanical modeling provides more accurate data for neuronavigation than rigid registration

    PubMed Central

    Garlapati, Revanth Reddy; Roy, Aditi; Joldes, Grand Roman; Wittek, Adam; Mostayed, Ahmed; Doyle, Barry; Warfield, Simon Keith; Kikinis, Ron; Knuckey, Neville; Bunt, Stuart; Miller, Karol

    2015-01-01

    It is possible to improve neuronavigation during image-guided surgery by warping the high-quality preoperative brain images so that they correspond with the current intraoperative configuration of the brain. In this work, the accuracy of registration results obtained using comprehensive biomechanical models is compared to the accuracy of rigid registration, the technology currently available to patients. This comparison allows us to investigate whether biomechanical modeling provides good quality image data for neuronavigation for a larger proportion of patients than rigid registration. Preoperative images for 33 cases of neurosurgery were warped onto their respective intraoperative configurations using both biomechanics-based method and rigid registration. We used a Hausdorff distance-based evaluation process that measures the difference between images to quantify the performance of both methods of registration. A statistical test for difference in proportions was conducted to evaluate the null hypothesis that the proportion of patients for whom improved neuronavigation can be achieved, is the same for rigid and biomechanics-based registration. The null hypothesis was confidently rejected (p-value<10−4). Even the modified hypothesis that less than 25% of patients would benefit from the use of biomechanics-based registration was rejected at a significance level of 5% (p-value = 0.02). The biomechanics-based method proved particularly effective for cases experiencing large craniotomy-induced brain deformations. The outcome of this analysis suggests that our nonlinear biomechanics-based methods are beneficial to a large proportion of patients and can be considered for use in the operating theatre as one possible method of improving neuronavigation and surgical outcomes. PMID:24460486

  13. Neuronavigation-guided focused ultrasound-induced blood-brain barrier opening: A preliminary study in swine

    NASA Astrophysics Data System (ADS)

    Liu, Hao-Li; Tsai, Hong-Chieh; Lu, Yu-Jen; Wei, Kuo-Chen

    2012-11-01

    FUS-induced BBB opening is a promising technique for noninvasive and local delivery of drugs into the brain. Here we propose the novel use of a neuronavigation system to guide the FUS-induced BBB opening procedure, and investigate its feasibility in vivo in large animals. We developed an interface between the neuronavigator and FUS to allow guidance of the focal energy produced by the FUS transducer. The system was tested in 29 pigs by more than 40 sonication procedures and evaluated by MRI. Gd-DTPA concentration was quantitated in vivo by MRI R1 relaxometry and compared by ICP-OES assay. Brain histology after FUS exposure was investigated by HE and TUNEL staining. Neuronavigation could successfully guide the focal beam with comparable precision to neurosurgical stereotactic procedures (2.3 ± 0.9 mm). FUS pressure of 0.43 MPa resulted in consistent BBB-opening. Neuronavigation-guided BBB-opening increased Gd-DTPA deposition by up to 1.83 mM (140% increase). MR relaxometry demonstrated high correlation to ICP-OES measurements (r2 = 0.822), suggesting that Gd-DTPA deposition can be directly measured by imaging. Neuronavigation could provide sufficient precision for guiding FUS to temporally and locally open the BBB. Gd-DTPA deposition in the brain could be quantified by MR relaxometry, providing a potential tool for the in vivo quantification of therapeutic agents in CNS disease treatment.

  14. Integration of 3D 1H-magnetic resonance spectroscopy data into neuronavigation systems for tumor biopsies

    NASA Astrophysics Data System (ADS)

    Kanberoglu, Berkay; Moore, Nina Z.; Frakes, David; Karam, Lina J.; Debbins, Josef P.; Preul, Mark C.

    2013-03-01

    Many important applications in clinical medicine can benefit from the fusion of spectroscopy data with anatomical images. For example, the correlation of metabolite profiles with specific regions of interest in anatomical tumor images can be useful in characterizing and treating heterogeneous tumors that appear structurally homogeneous. Such applications can build on the correlation of data from in-vivo Proton Magnetic Resonance Spectroscopy Imaging (1HMRSI) with data from genetic and ex-vivo Nuclear Magnetic Resonance spectroscopy. To establish that correlation, tissue samples must be neurosurgically extracted from specifically identified locations with high accuracy. Toward that end, this paper presents new neuronavigation technology that enhances current clinical capabilities in the context of neurosurgical planning and execution. The proposed methods improve upon the current state-of-the-art in neuronavigation through the use of detailed three dimensional (3D) 1H-MRSI data. MRSI spectra are processed and analyzed, and specific voxels are selected based on their chemical contents. 3D neuronavigation overlays are then generated and applied to anatomical image data in the operating room. Without such technology, neurosurgeons must rely on memory and other qualitative resources alone for guidance in accessing specific MRSI-identified voxels. In contrast, MRSI-based overlays provide quantitative visual cues and location information during neurosurgery. The proposed methods enable a progressive new form of online MRSI-guided neuronavigation that we demonstrate in this study through phantom validation and clinical application.

  15. 3D-neuronavigation in vivo through a patient's brain during a spontaneous migraine headache.

    PubMed

    DaSilva, Alexandre F; Nascimento, Thiago D; Love, Tiffany; DosSantos, Marcos F; Martikainen, Ilkka K; Cummiford, Chelsea M; DeBoer, Misty; Lucas, Sarah R; Bender, MaryCatherine A; Koeppe, Robert A; Hall, Theodore; Petty, Sean; Maslowski, Eric; Smith, Yolanda R; Zubieta, Jon-Kar

    2014-01-01

    A growing body of research, generated primarily from MRI-based studies, shows that migraine appears to occur, and possibly endure, due to the alteration of specific neural processes in the central nervous system. However, information is lacking on the molecular impact of these changes, especially on the endogenous opioid system during migraine headaches, and neuronavigation through these changes has never been done. This study aimed to investigate, using a novel 3D immersive and interactive neuronavigation (3D-IIN) approach, the endogenous µ-opioid transmission in the brain during a migraine headache attack in vivo. This is arguably one of the most central neuromechanisms associated with pain regulation, affecting multiple elements of the pain experience and analgesia. A 36 year-old female, who has been suffering with migraine for 10 years, was scanned in the typical headache (ictal) and nonheadache (interictal) migraine phases using Positron Emission Tomography (PET) with the selective radiotracer [(11)C]carfentanil, which allowed us to measure µ-opioid receptor availability in the brain (non-displaceable binding potential - µOR BPND). The short-life radiotracer was produced by a cyclotron and chemical synthesis apparatus on campus located in close proximity to the imaging facility. Both PET scans, interictal and ictal, were scheduled during separate mid-late follicular phases of the patient's menstrual cycle. During the ictal PET session her spontaneous headache attack reached severe intensity levels; progressing to nausea and vomiting at the end of the scan session. There were reductions in µOR BPND in the pain-modulatory regions of the endogenous µ-opioid system during the ictal phase, including the cingulate cortex, nucleus accumbens (NAcc), thalamus (Thal), and periaqueductal gray matter (PAG); indicating that µORs were already occupied by endogenous opioids released in response to the ongoing pain. To our knowledge, this is the first time that changes

  16. Cavernous sinus lesions biopsy with neuronavigation and tip-cut needle

    PubMed Central

    Lorenzetti, Martin; Carvalho, Herculano; Cattoni, Maria; Gonçalves-Ferreira, Antonio; Pimentel, José; Antuñes, Joao

    2014-01-01

    Background: Transoval biopsy of cavernous sinus (CS) lesions is the last non-invasive diagnostic option in those 15% of patients in whom etiology remains unclear in spite of extensive neuroradiological imaging, clinical assessment, and laboratory evaluation. However, there are no guidelines defining indications and the most appropriate technique for this procedure. Case Description: We present four patients in whom we performed X-ray and neuronavigation-assisted transoval CS biopsies using tip-cut needles. Conclusion: The technique described allows the operator to determine the optimal angle for entering the CS, avoiding the complications due to distorted anatomy, and facilitating orientation once inside the CS. It reduces both radiation exposure as well as general anesthesia duration. PMID:25593783

  17. Resting state functional connectivity magnetic resonance imaging integrated with intraoperative neuronavigation for functional mapping after aborted awake craniotomy

    PubMed Central

    Batra, Prag; Bandt, S. Kathleen; Leuthardt, Eric C.

    2016-01-01

    Background: Awake craniotomy is currently the gold standard for aggressive tumor resections in eloquent cortex. However, a significant subset of patients is unable to tolerate this procedure, particularly the very young or old or those with psychiatric comorbidities, cardiopulmonary comorbidities, or obesity, among other conditions. In these cases, typical alternative procedures include biopsy alone or subtotal resection, both of which are associated with diminished surgical outcomes. Case Description: Here, we report the successful use of a preoperatively obtained resting state functional connectivity magnetic resonance imaging (MRI) integrated with intraoperative neuronavigation software in order to perform functional cortical mapping in the setting of an aborted awake craniotomy due to loss of airway. Conclusion: Resting state functional connectivity MRI integrated with intraoperative neuronavigation software can provide an alternative option for functional cortical mapping in the setting of an aborted awake craniotomy. PMID:26958419

  18. Functional magnetic resonance imaging for cranial neuronavigation: methods for automated and standardized data processing and management. A technical note.

    PubMed

    Nennig, E; Heiland, S; Rasche, D; Sartor, K; Stippich, C

    2007-04-30

    Preoperative fMRI is one of the best established clinical fMRI applications. Due to the difficulties in recording and coregistration of functional image data, we present methods to standardize and automate these procedures. We used a self-made interactive software package (AFI - Automated Functional Imaging) to automate the time consuming and complex analysis of fMRI data. AFI controls the BrainVoyager program, a postprocessing software package, and furthermore facilitates data management, anonymization of patient data, storage, documentation, data export to neuronavigation systems and the opportunity of spatial transformation of image data for use in group studies. By the end of 2006 we have used this method on 123 patients with brain tumors and 47 patients with trigeminal neuralgia. The fundamental basis of multimodal neuronavigation is precise coregistration. EPI images contain spatial distortions of 5-15 mm. We were able to reduce the misregistration of EPI and FLASH images in a selectable region of interest to 1-2 mm. Furthermore AFI reduces the average evaluation time for a standard clinical fMRI study (four functional measurements, one anatomical data set) by approx. 50% from 140 minutes to about 70 minutes in comparison to manual evaluation by an expert. More importantly, the personal attendance time required for the evaluation decreases by 84% to 23 minutes as the remainder of the program runs automatically. In comparison to currently available online postprocessing software tools which are more limited in use, BrainVoyager can be used for coregistration, data export to neuronavigation systems and spatial transformation. PMID:24299636

  19. Utility of diffusion tensor imaging studies linked to neuronavigation and other modalities in repeat hemispherotomy for intractable epilepsy.

    PubMed

    Kiehna, Erin N; Widjaja, Elysa; Holowka, Stephanie; Carter Snead, O; Drake, James; Weiss, Shelly K; Ochi, Ayako; Thompson, Eric M; Go, Cristina; Otsubo, Hiroshi; Donner, Elizabeth J; Rutka, James T

    2016-04-01

    OBJECT Hemispherectomy for unilateral, medically refractory epilepsy is associated with excellent long-term seizure control. However, for patients with recurrent seizures following disconnection, workup and investigation can be challenging, and surgical options may be limited. Few studies have examined the role of repeat hemispherotomy in these patients. The authors hypothesized that residual fiber connections between the hemispheres could be the underlying cause of recurrent epilepsy in these patients. Diffusion tensor imaging (DTI) was used to test this hypothesis, and to target residual connections at reoperation using neuronavigation. METHODS The authors identified 8 patients with recurrent seizures following hemispherectomy who underwent surgery between 1995 and 2012. Prolonged video electroencephalography recordings documented persistent seizures arising from the affected hemisphere. In all patients, DTI demonstrated residual white matter association fibers connecting the hemispheres. A repeat craniotomy and neuronavigation-guided targeted disconnection of these residual fibers was performed. Engel class was used to determine outcome after surgery at a minimum of 2 years of follow-up. RESULTS Two patients underwent initial hemidecortication and 6 had periinsular hemispherotomy as their first procedures at a median age of 9.7 months. Initial pathologies included hemimegalencephaly (n = 4), multilobar cortical dysplasia (n = 3), and Rasmussen's encephalitis (n = 1). The mean duration of seizure freedom for the group after the initial procedure was 32.5 months (range 6-77 months). In all patients, DTI showed limited but definite residual connections between the 2 hemispheres, primarily across the rostrum/genu of the corpus callosum. The median age at reoperation was 6.8 years (range 1.3-14 years). The average time taken for reoperation was 3 hours (range 1.8-4.3 hours), with a mean blood loss of 150 ml (range 50-250 ml). One patient required a blood transfusion

  20. Resective surgery for medically refractory epilepsy using intraoperative MRI and functional neuronavigation: the Erlangen experience of 415 patients.

    PubMed

    Roessler, Karl; Hofmann, Andrea; Sommer, Bjoern; Grummich, Peter; Coras, Roland; Kasper, Burkard Sebastian; Hamer, Hajo M; Blumcke, Ingmar; Stefan, Hermann; Nimsky, Christopher; Buchfelder, Michael

    2016-03-01

    OBJECTIVE Intraoperative overestimation of resection volume in epilepsy surgery is a well-known problem that can lead to an unfavorable seizure outcome. Intraoperative MRI (iMRI) combined with neuronavigation may help surgeons avoid this pitfall and facilitate visualization and targeting of sometimes ill-defined heterogeneous lesions or epileptogenic zones and may increase the number of complete resections and improve seizure outcome. METHODS To investigate this hypothesis, the authors conducted a retrospective clinical study of consecutive surgical procedures performed during a 10-year period for epilepsy in which they used neuronavigation combined with iMRI and functional imaging (functional MRI for speech and motor areas; diffusion tensor imaging for pyramidal, speech, and visual tracts; and magnetoencephalography and electrocorticography for spike detection). Altogether, there were 415 patients (192 female and 223 male, mean age 37.2 years; 41% left-sided lesions and 84.9% temporal epileptogenic zones). The mean preoperative duration of epilepsy was 17.5 years. The most common epilepsy-associated pathologies included hippocampal sclerosis (n = 146 [35.2%]), long-term epilepsy-associated tumor (LEAT) (n = 67 [16.1%]), cavernoma (n = 45 [10.8%]), focal cortical dysplasia (n = 31 [7.5%]), and epilepsy caused by scar tissue (n = 23 [5.5%]). RESULTS In 11.8% (n = 49) of the surgeries, an intraoperative second-look surgery (SLS) after incomplete resection verified by iMRI had to be performed. Of those incomplete resections, LEATs were involved most often (40.8% of intraoperative SLSs, 29.9% of patients with LEAT). In addition, 37.5% (6 of 16) of patients in the diffuse glioma group and 12.9% of the patients with focal cortical dysplasia underwent an SLS. Moreover, iMRI provided additional advantages during implantation of grid, strip, and depth electrodes and enabled intraoperative correction of electrode position in 13.0% (3 of 23) of the cases. Altogether, an

  1. Intraoperative magnetic resonance imaging versus standard neuronavigation for the neurosurgical treatment of glioblastoma: A randomized controlled trial

    PubMed Central

    Kubben, Pieter L.; Scholtes, Felix; Schijns, Olaf E.M.G.; ter Laak-Poort, Mariël P.; Teernstra, Onno P.M.; Kessels, Alfons G. H.; van Overbeeke, Jacobus J.; Martin, Didier H.; van Santbrink, Henk

    2014-01-01

    Background: Although the added value of increasing extent of glioblastoma resection is still debated, multiple technologies can assist neurosurgeons in attempting to achieve this goal. Intraoperative magnetic resonance imaging (iMRI) might be helpful in this context, but to date only one randomized trial exists. Methods: We included 14 adults with a supratentorial tumor suspect for glioblastoma and an indication for gross total resection in this randomized controlled trial of which the interim analysis is presented here. Participants were assigned to either ultra-low-field strength iMRI-guided surgery (0.15 Tesla) or to conventional neuronavigation-guided surgery (cNN). Primary endpoint was residual tumor volume (RTV) percentage. Secondary endpoints were clinical performance, health-related quality of life (HRQOL) and survival. Results: Median RTV in the cNN group is 6.5% with an interquartile range of 2.5-14.75%. Median RTV in the iMRI group is 13% with an interquartile range of 3.75-27.75%. A Mann-Whitney test showed no statistically significant difference between these groups (P =0.28). Median survival in the cNN group is 472 days, with an interquartile range of 244-619 days. Median survival in the iMRI group is 396 days, with an interquartile range of 191-599 days (P =0.81). Clinical performance did not differ either. For HRQOL only descriptive statistics were applied due to a limited sample size. Conclusion: This interim analysis of a randomized trial on iMRI-guided glioblastoma resection compared with cNN-guided glioblastoma resection does not show an advantage with respect to extent of resection, clinical performance, and survival for the iMRI group. Ultra-low-field strength iMRI does not seem to be cost-effective compared with cNN, although the lack of a valid endpoint for neurosurgical studies evaluating extent of glioblastoma resection is a limitation of our study and previous volumetry-based studies on this topic. PMID:24991473

  2. [Treatment of central and neuropathic facial pain by chronic stimulation of the motor cortex: value of neuronavigation guidance systems for the localization of the motor cortex].

    PubMed

    Nguyen, J P; Lefaucheur, J P; Le Guerinel, C; Fontaine, D; Nakano, N; Sakka, L; Eizenbaum, J F; Pollin, B; Keravel, Y

    2000-11-01

    Thirty two patients with refractory central and neuropathic pain of peripheral origin were treated by chronic stimulation of the motor cortex between May 1993 and January 1997. The mean follow-up was 27. 3 months. The first 24 patients were operated according to the technique described by Tsubokawa. The last 13 cases (8 new patients and 5 reinterventions) were operated by a technique including localization by superficial CT reconstruction of the central region and neuronavigator guidance. The position of the central sulcus was confirmed by the use of intraoperative somatosensory evoked potentials. The somatotopic organisation of the motor cortex was established peroperatively by studying the motor responses at stimulation of the motor cortex through the dura. Ten of the 13 patients with central pain (77%) and nine of the 12 patients with neuropathic facial pain had experienced substantial pain relief (75%). One of the 3 patients with post-paraplegia pain was clearly improved. A satisfactory result was obtained in one patient with pain related to plexus avulsion and in one patient with pain related to intercostal herpes zoster. None of the patients developed epileptic seizures. The position of the stimulating poles effective on pain corresponded to the somatotopic representation of the motor cortex. The neuronavigator localization and guidance technique proved to be most useful identifying the appropriate portion of the motor gyrus. It also allowed the establishment of reliable correlations between electrophysiological-clinical and anatomical data which may be used to improve the clinical results and possibly to extend the indications of this technique. PMID:11084480

  3. Intraoperative high-field magnetic resonance imaging combined with neuronavigation-guided resection of intracranial mesenchymal chondrosarcoma in Broca’s area: a rare case report and literature review

    PubMed Central

    Yan, Jing; Cheng, Jingliang; Li, Hongwei; Liu, Xianzhi; Zheng, Yuan; Wang, Chaoyan; Luo, Wenzheng; Nie, Yunfei; Li, Zhengwei; Pang, Beibei; Yang, Bo

    2015-01-01

    Cranial Mesenchymal chondrosarcoma (MC) and those that occurred in brain parenchymal were fairly rare aggressive neoplasm commonly affecting the bone of young adults. Here, we reported a case with intracranial MC, invading Broca’s area, a rare site not previously reported, which was presumed to be a glioma. We performed a gross total resection guided by intra-operative magnetic resonance imaging (iMRI) combined with neuronavigation. Follow-up shows no language and other brain function loss. Furthermore, we present a review of literature. We emphasized the importance of gross total resection guiding by the combination of iMRI and neuronavigation, which was proved to be both reliable and effective in language preservation. PMID:26064406

  4. Intraoperative neurosonography revisited: effective neuronavigation in pediatric neurosurgery

    PubMed Central

    2015-01-01

    Intraoperative ultrasonography (IOUS) is a widely used noninvasive method to evaluate the morphology, vasculature, and pathologies of the brain. The advantages of IOUS include realtime depiction of neuroanatomy, accurate localization and characterization of a lesion, reduced surgical exploration and surgical time, and presumably decreased patient morbidity. IOUS is useful in the intraoperative monitoring of lesion resection as well as intraoperative localization and characterization of focal parenchymal lesions. This review aims to provide an overview of the clinical application of IOUS in pediatric intracranial neurosurgery. PMID:25672771

  5. [The use of frameless neuronavigation in the surgery of hemorrhagic stroke].

    PubMed

    Krylov, V V; Dash'ian, V G; Shaklunov, A A; Burov, S A

    2008-01-01

    The application of CT-navigation in emergency neurosurgery for the calculation of surgery assets in 42 patients with hypertensive intracranial hemorrhages is presented. The relative simplicity and high precision of navigation (on average 2,2 +/- 1 mm) made it possible to use the method in emergency surgery of deep intracranial hematomas. The application of CT navigation in combination with neuroendoscopy and local fibrinolysis of hemorrhages allowed to decrease the post-surgery brain trauma and reduce the volume of intervention due to the high precision of calculation that resulted in the improvement of surgical outcome. The total post-operative mortality was 24%. In 94% of survived patients positive changes in neurological status were observed in 2-4 weeks after the surgery. PMID:19431271

  6. Neuronavigation using susceptibility-weighted venography: application to deep brain stimulation and comparison with gadolinium contrast.

    PubMed

    Bériault, Silvain; Sadikot, Abbas F; Alsubaie, Fahd; Drouin, Simon; Collins, D Louis; Pike, G Bruce

    2014-07-01

    Careful trajectory planning on preoperative vascular imaging is an essential step in deep brain stimulation (DBS) to minimize risks of hemorrhagic complications and postoperative neurological deficits. This paper compares 2 MRI methods for visualizing cerebral vasculature and planning DBS probe trajectories: a single data set T1-weighted scan with double-dose gadolinium contrast (T1w-Gd) and a multi-data set protocol consisting of a T1-weighted structural, susceptibility-weighted venography, and time-of-flight angiography (T1w-SWI-TOF). Two neurosurgeons who specialize in neuromodulation surgery planned bilateral STN DBS in 18 patients with Parkinson's disease (36 hemispheres) using each protocol separately. Planned trajectories were then evaluated across all vascular data sets (T1w-Gd, SWI, and TOF) to detect possible intersection with blood vessels along the entire path via an objective vesselness measure. The authors' results show that trajectories planned on T1w-SWI-TOF successfully avoided the cerebral vasculature imaged by conventional T1w-Gd and did not suffer from missing vascular information or imprecise data set registration. Furthermore, with appropriate planning and visualization software, trajectory corridors planned on T1w-SWI-TOF intersected significantly less fine vasculature that was not detected on the T1w-Gd (p < 0.01 within 2 mm and p < 0.001 within 4 mm of the track centerline). The proposed T1w-SWI-TOF protocol comes with minimal effects on the imaging and surgical workflow, improves vessel avoidance, and provides a safe cost-effective alternative to injection of gadolinium contrast. PMID:24834941

  7. Improving neuronavigation through workflow and sound feedback and interactive brainshift correction

    NASA Astrophysics Data System (ADS)

    Noordmans, H. J.; Woerdeman, P. A.; Voormolen, E. H. J.; van der Steen, S.; van Stralen, M.

    2011-07-01

    In neurosurgery, navigation is being used to improve surgical orientation by using preoperative images as a roadmap. Skin or bone fiducials couple the image coordinate system to that of the patient's head fixed by the Mayfield clamp. Then the tip of a pointer of another instrument (localization device) can be seen in relation to the image to give the surgeon insight where he/she is in the brain and where the tumor or lesion can be expected in the depth. Drawbacks from current navigation systems are that 1) they only show the actual position of the localization device and thus do not hint whether the surgeon has removed the tumor completely, 2) don't warn when the device is about to hit a critical brain structure, and 3) do not compensate for shifts of the brain during surgery invalidating the pre-operative image data. During the last 5 years we investigated in our hospital whether sound and workflow feedback could improve the surgical resection accuracy and looked how the pre-operative image data could be deformed in real-time using GPU hardware to match the tracked cortical surface to compensate for brain shifts.

  8. A Randomised Controlled Trial of Neuronavigated Repetitive Transcranial Magnetic Stimulation (rTMS) in Anorexia Nervosa

    PubMed Central

    McClelland, Jessica; Kekic, Maria; Bozhilova, Natali; Nestler, Steffen; Dew, Tracy; Van den Eynde, Frederique; David, Anthony S.; Rubia, Katya; Campbell, Iain C.; Schmidt, Ulrike

    2016-01-01

    Background Anorexia nervosa (AN) is associated with morbid fear of fatness, extreme food restriction and altered self-regulation. Neuroimaging data implicate fronto-striatal circuitry, including the dorsolateral prefrontal cortex (DLPFC). Methods In this double-blind parallel group study, we investigated the effects of one session of sham-controlled high-frequency repetitive transcranial magnetic stimulation (rTMS) to the left DLPFC (l-DLPFC) in 60 individuals with AN. A food exposure task was administered before and after the procedure to elicit AN-related symptoms. Outcomes The primary outcome measure was ‘core AN symptoms’, a variable which combined several subjective AN-related experiences. The effects of rTMS on other measures of psychopathology (e.g. mood), temporal discounting (TD; intertemporal choice behaviour) and on salivary cortisol concentrations were also investigated. Safety, tolerability and acceptability were assessed. Results Fourty-nine participants completed the study. Whilst there were no interaction effects of rTMS on core AN symptoms, there was a trend for group differences (p = 0.056): after controlling for pre-rTMS scores, individuals who received real rTMS had reduced symptoms post-rTMS and at 24-hour follow-up, relative to those who received sham stimulation. Other psychopathology was not altered differentially following real/sham rTMS. In relation to TD, there was an interaction trend (p = 0.060): real versus sham rTMS resulted in reduced rates of TD (more reflective choice behaviour). Salivary cortisol concentrations were unchanged by stimulation. rTMS was safe, well–tolerated and was considered an acceptable intervention. Conclusions This study provides modest evidence that rTMS to the l-DLPFC transiently reduces core symptoms of AN and encourages prudent decision making. Importantly, individuals with AN considered rTMS to be a viable treatment option. These findings require replication in multiple-session studies to evaluate therapeutic efficacy. Trial Registration www.Controlled-Trials.com ISRCTN22851337 PMID:27008620

  9. Integration of intraoperative and model-updated images into an industry-standard neuronavigation system: initial results

    NASA Astrophysics Data System (ADS)

    Schaewe, Timothy J.; Fan, Xiaoyao; Ji, Songbai; Hartov, Alex; Hiemenz Holton, Leslie; Roberts, David W.; Paulsen, Keith D.; Simon, David A.

    2013-03-01

    Dartmouth and Medtronic have established an academic-industrial partnership to develop, validate, and evaluate a multimodality neurosurgical image-guidance platform for brain tumor resection surgery that is capable of updating the spatial relationships between preoperative images and the current surgical field. Previous studies have shown that brain shift compensation through a modeling framework using intraoperative ultrasound and/or visible light stereovision to update preoperative MRI appears to result in improved accuracy in navigation. However, image updates have thus far only been produced retrospective to surgery in large part because of gaps in the software integration and information flow between the co-registration and tracking, image acquisition and processing, and image warping tasks which are required during a case. This paper reports the first demonstration of integration of a deformation-based image updating process for brain shift modeling with an industry-standard image guided surgery platform. Specifically, we have completed the first and most critical data transfer operation to transmit volumetric image data generated by the Dartmouth brain shift modeling process to the Medtronic StealthStation® system. StealthStation® comparison views, which allow the surgeon to verify the correspondence of the received updated image volume relative to the preoperative MRI, are presented, along with other displays of image data such as the intraoperative 3D ultrasound used to update the model. These views and data represent the first time that externally acquired and manipulated image data has been imported into the StealthStation® system through the StealthLink® portal and visualized on the StealthStation® display.

  10. Screw Placement Accuracy for Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgery: A Study on 3-D Neuronavigation-Guided Surgery

    PubMed Central

    Torres, Jorge; James, Andrew R.; Alimi, Marjan; Tsiouris, Apostolos John; Geannette, Christian; Härtl, Roger

    2012-01-01

    Purpose The aim of this study was to assess the impact of 3-D navigation for pedicle screw placement accuracy in minimally invasive transverse lumbar interbody fusion (MIS-TLIF). Methods A retrospective review of 52 patients who had MIS-TLIF assisted with 3D navigation is presented. Clinical outcomes were assessed with the Oswestry Disability Index (ODI), Visual Analog Scales (VAS), and MacNab scores. Radiographic outcomes were assessed using X-rays and thin-slice computed tomography. Result The mean age was 56.5 years, and 172 screws were implanted with 16 pedicle breaches (91.0% accuracy rate). Radiographic fusion rate at a mean follow-up of 15.6 months was 87.23%. No revision surgeries were required. The mean improvement in the VAS back pain, VAS leg pain, and ODI at 11.3 months follow-up was 4.3, 4.5, and 26.8 points, respectively. At last follow-up the mean postoperative disc height gain was 4.92 mm and the mean postoperative disc angle gain was 2.79 degrees. At L5–S1 level, there was a significant correlation between a greater disc space height gain and a lower VAS leg score. Conclusion Our data support that application of 3-D navigation in MIS-TLIF is associated with a high level of accuracy in the pedicle screw placement. PMID:24353961

  11. The Hand Motor Hotspot is not Always Located in the Hand Knob: A Neuronavigated Transcranial Magnetic Stimulation Study.

    PubMed

    Ahdab, Rechdi; Ayache, Samar S; Brugières, Pierre; Farhat, Wassim H; Lefaucheur, Jean-Pascal

    2016-07-01

    The hand motor hot spot (hMHS) is one of the most salient parameters in transcranial magnetic stimulation (TMS) practice, notably used for targeting. It is commonly accepted that the hMHS corresponds to the hand representation within the primary motor cortex (M1). Anatomical and imaging studies locate this representation in a region of the central sulcus called the "hand knob". The aim of this study was to determine if the hMHS location corresponds to its expected location at the hand knob. Twelve healthy volunteers and eleven patients with chronic neuropathic pain of various origins, but not related to a brain lesion, were enrolled. Morphological magnetic resonance imaging of the brain was normal in all participants. Both hemispheres were studied in all participants except four (two patients and two healthy subjects). Cortical mapping of the hand motor area was conducted using a TMS-dedicated navigation system and recording motor evoked potentials (MEPs) in the contralateral first dorsal interosseous (FDI) muscle. We then determined the anatomical position of the hMHS, defined as the stimulation site providing the largest FDI-MEPs. In 45 % of hemispheres of normal subjects and 25 % of hemispheres of pain patients, the hMHS was located over the central sulcus, most frequently at the level of the hand knob. However, in the other cases, the hMHS was located outside M1, most frequently anteriorly over the precentral or middle frontal gyrus. This study shows that the hMHS does not always correspond to the hand knob and M1 location in healthy subjects or patients. Therefore, image-guided navigation is needed to improve the anatomical accuracy of TMS targeting, even for M1. PMID:26980192

  12. Navigated laser-assisted endoscopic fenestration of a suprasellar arachnoid cyst in a 2-year-old child with bobble-head doll syndrome. Case report.

    PubMed

    Van Beijnum, Janneke; Hanlo, Patrick W; Han, K Sen; Ludo Van der Pol, W; Verdaasdonk, Rudolf M; Van Nieuwenhuizen, Onno

    2006-05-01

    The authors present the case of a 2-year-old boy with bobble-head doll syndrome (BHDS) associated with a large suprasellar arachnoid cyst and enlarged ventricles, who was successfully treated with neuronavigated laser-assisted endoscopic ventriculocystocisternostomy. The clinical history, surgical treatment, and clinical follow up of the patient are described. A navigated laser-assisted endoscopic ventriculocystocisternostomy of the suprasellar arachnoid cyst led to cessation of the head bobbing, and notable reduction of the cyst and ventricles was visible on the postoperative magnetic resonance images. Caused by a suprasellar arachnoid cyst, BHDS can be successfully treated with navigated laser-assisted endoscopic ventriculocystocisternostomy. The advantages of this procedure are minimal invasiveness and facilitated guidance of the neuronavigation system to the target area when normal anatomical landmarks are not visible. PMID:16848093

  13. BRAIN initiative: transcranial magnetic stimulation automation and calibration.

    PubMed

    Todd, Garth D; Abdellatif, Ahmed; Sabouni, Abas

    2014-01-01

    In this paper, we introduced an automated TMS system with robot control and optical sensor combined with neuronavigation software. By using the robot, the TMS coil can be accurately positioned over any preselected brain region. The neuronavigation system provides an accurate positioning of a magnetic coil in order to induce a specific cortical excitation. An infrared optical measurement device is also used in order to detect and compensate for head movements of the patient. This procedure was simulated using a PC based robotic simulation program. The proposed automated robot system is integrated with TMS numerical solver and allows users to actually see the depth, location, and shape of the induced eddy current on the computer monitor. PMID:25570006

  14. Repetitive transcranial magnetic stimulation (rTMS) in schizophrenia with treatment-refractory auditory hallucinations and major self-mutilation.

    PubMed

    Schulz, Torsten; Berger, Christoph; Krecklow, Beate; Kurth, Jens; Schwarzenboeck, Sarah; Foley, Paul; Thome, Johannes; Krause, Bernd Joachim; Hoeppner, Jacqueline

    2015-08-01

    Major self-mutilation is one of the most hazardous complications encountered in psychiatric patients, and is generally associated with auditory verbal hallucinations as part of a psychotic syndrome. This case report exemplarily discusses the treatment of such hallucinations with repeated (20 sessions) low-frequency (1 Hz) transcranial magnetic stimulation targeting areas of elevated metabolic activity in the temporo-parietal cortex ('neuronavigated rTMS'), drawing upon experience concerning treatment of a patient with chronic auditory verbal hallucinations that had proved intractable to antipsychotic medication combined with cognitive behavioural therapy, and who had severed a forearm because of the content of these hallucinations. This example of major self-mutilation underscores the urgent requirement for effective management of chronic auditory verbal hallucinations in patients suffering from psychiatric disease, and neuronavigated rTMS represents an approach that deserves further exploration in this regard. PMID:24398780

  15. Usefulness of Image Guidance in the Surgical Treatment of Petrous Apex Cholesterol Granuloma

    PubMed Central

    Pietrantonio, A.; D'Andrea, G.; Famà, I.; Volpini, L.; Raco, A.; Barbara, M.

    2013-01-01

    The petrous apex is a pyramid-shaped structure, located medial to the inner ear and the intrapetrous segment of the internal carotid artery. Lesions of the petrous apex can be surgically treated through different surgical routes. Because of the important neurovascular structures located inside the temporal bone, anatomical 3D knowledge is paramount. For this reason, image-guided surgery could represent a useful tool. We report the case of a young woman who came to our observation for a trigeminal neuralgia due to a petrous apex cholesterol granuloma. The lesion was treated through the placement of a drainage tube via an infracochlear approach, with the aid of neuronavigation and intraoperative MRI. Preoperative CT scan images and intraoperative MRI images were fused for surgical planning. The accuracy of the neuronavigation system has proved to be good, and the safety of the procedure was enhanced. Therefore, neuronavigation and intraoperative MRI, though not available in all neurootological centres, should be considered useful tools in these challenging procedures. PMID:24251056

  16. Preliminary experience with an intraoperative MRI-compatible infant headholder: technical note.

    PubMed

    Boop, Frederick A; Bate, Berkeley; Choudhri, Asim F; Burkholder, Brian; Klimo, Paul

    2015-05-01

    The development of high-quality intraoperative MRI (iMRI) capability has offered a major advance in the care of patients with complex intracranial disease. To date, this technology has been limited by the need for pin fixation of the calvaria. The authors report their preliminary experience with an MRI-compatible horseshoe headrest that allows for the following: 1) iMRI in patients too young for pin fixation; 2) iMRI in patients with large calvarial defects; 3) the ability to move the head during iMRI surgery; and 4) the use of neuronavigation in such cases. The authors report 2 cases of infants in whom the Visius Surgical Theatre horseshoe headrest (IMRIS Inc.) was used. Image quality was equivalent to that of pin fixation. The infants suffered no skin issues. The use of neuronavigation with the system remained accurate and could be updated with the new iMRI information. The Visius horseshoe headrest offers a technical advance in iMRI technology for infants, for patients with cranial defects or prior craniotomies in whom pin fixation may not be safe, or for patients in whom the need to move the head during surgery is required. The image quality of the system remains excellent, and the ability to merge new images to the neuronavigation system is helpful. PMID:25679382

  17. From the Idea to Its Realization: The Evolution of Minimally Invasive Techniques in Neurosurgery

    PubMed Central

    Grunert, P.

    2013-01-01

    Minimally invasive techniques in neurosurgery evolved in two steps. Many minimally invasive concepts like neuronavigation, endoscopy, or frame based stereotaxy were developed by the pioneers of neurosurgery, but it took decades till further technical developments made the realization and broad clinical application of these early ideas safe and possible. This thesis will be demonstrated by giving examples of the evolution of four minimally invasive techiques: neuronavigation, transsphenoidal pituitary surgery, neuroendoscopy and stereotaxy. The reasons for their early failure and also the crucial steps for the rediscovery of these minimally invasive techniques will be analysed. In the 80th of the 20th century endoscopy became increasingly applied in different surgical fields. The abdominal surgeons coined as first for their endoscopic procedures the term minimally invasive surgery in contrast to open surgery. In neurrosurgery the term minimally invasive surgery stood not in opposiotion to open procedures but was understood as a general concept and philosophy using the modern technology such as neuronavigation, endoscopy and planing computer workstations with the aim to make the procedures less traumatic. PMID:24455231

  18. Ventriculoscopic surgery for arachnoid cysts in the lateral ventricle: a comparative study of 21 consecutive cases

    PubMed Central

    Shou, Xuefei; Zhao, Yao; Li, Shiqi; Wang, Yongfei

    2015-01-01

    Objective: To evaluate neuronavigation-guided ventriculoscopic technique in the treatment of arachnoid cysts in the lateral ventricle. Methods: Between January 2008 to November 2011, twenty-one neuronavigationguided ventriculoscopic surgery were performed for the treatment of symptomatic arachnoid cysts in 21 patients (14 male and 7 female patients, mean age 24.1 years [ranged 1.5-61 years]) Clinical presentations varied from headache, vomiting, hemiparesis and seizure. The trajectory of ventriculoscopy was dynamically monitored and guided in real time by neuronavigation system. Cysts fenestrations were performed in fourteen cases, and cysts resection in seven cases, respectively. All patients were prospectively had a regular follow-up. Results: After operation, all patients achieved symptom resolution without surgical mortality and morbidity. Aseptic meningitis was noted in four cases with cyst resection, and all recovered quickly without advanced treatments. However, a later ependymal adhesion, occurred in one case during follow-up period. Conclusion: The combination of ventriculoscopy and neuronavigation is an accurate, effective and safe approach for the treatment of the patients with arachnoid cysts in the lateral ventricle, especially, for overcoming the topographic variation caused by intraventricular pathologies. Cystoventriculostomy is the best choice. PMID:26885002

  19. Computational Modeling for Enhancing Soft Tissue Image Guided Surgery: An Application in Neurosurgery

    PubMed Central

    Miga, Michael I.

    2016-01-01

    With the recent advances in computing, the opportunities to translate computational models to more integrated roles in patient treatment are expanding at an exciting rate. One area of considerable development has been directed towards correcting soft tissue deformation within image guided neurosurgery applications. This review captures the efforts that have been undertaken towards enhancing neuronavigation by the integration of soft tissue biomechanical models, imaging and sensing technologies, and algorithmic developments. In addition, the review speaks to the evolving role of modeling frameworks within surgery and concludes with some future directions beyond neurosurgical applications. PMID:26354118

  20. Intraoperative optical biopsy for brain tumors using spectro-lifetime properties of intrinsic fluorophores

    NASA Astrophysics Data System (ADS)

    Vasefi, Fartash; Kittle, David S.; Nie, Zhaojun; Falcone, Christina; Patil, Chirag G.; Chu, Ray M.; Mamelak, Adam N.; Black, Keith L.; Butte, Pramod V.

    2016-04-01

    We have developed and tested a system for real-time intra-operative optical identification and classification of brain tissues using time-resolved fluorescence spectroscopy (TRFS). A supervised learning algorithm using linear discriminant analysis (LDA) employing selected intrinsic fluorescence decay temporal points in 6 spectral bands was employed to maximize statistical significance difference between training groups. The linear discriminant analysis on in vivo human tissues obtained by TRFS measurements (N = 35) were validated by histopathologic analysis and neuronavigation correlation to pre-operative MRI images. These results demonstrate that TRFS can differentiate between normal cortex, white matter and glioma.

  1. Anesthesia during high-field intraoperative magnetic resonance imaging experience with 80 consecutive cases.

    PubMed

    Schmitz, Bernd; Nimsky, Christopher; Wendel, Georg; Wienerl, Juergen; Ganslandt, Oliver; Jacobi, Klaus; Fahlbusch, Rudolf; Schüttler, Juergen

    2003-07-01

    Intraoperative magnetic resonance imaging (MRI) has been used for years to update neuronavigation and for intraoperative resection control. For this purpose, low-field (0.1-0.2 T) MR scanners have been installed in the operating room, which, in contrast to machines using higher magnetic field strength, allowed the use of standard anesthetic and surgical equipment. However, these low-field MR systems provided only minor image quality and a limited battery of MR sequences, excluding functional MRI, diffusion-weighted MRI, or MR angiography and spectroscopy. Based on these advantages, a concept using high-field MRI (1.5 T) with intraoperative functional neuronavigational guidance has been developed that required adaptation of the anesthetic regimen to working in the close vicinity to the strong magnetic field. In this paper the authors present their experience with the first 80 consecutive patients who received anesthesia in a specially designed radio frequency-shielded operating room equipped with a high-field (1.5 T) MR scanner. We describe the MR-compatible anesthesia equipment used including ventilator, monitoring, and syringe pumps, which allow standard neuroanesthesia in this new and challenging environment. This equipment provides the use of total intravenous anesthesia with propofol and remifentanil allowing rapid extubation and neurologic examination following surgery. In addition, extended intraoperative monitoring including EEG monitoring required for intracranial surgery is possible. Moreover, problems and dangers related to the effects of the strong magnetic field are discussed. PMID:12826974

  2. Efficacy of endoport-guided endoscopic resection for deep-seated brain lesions.

    PubMed

    Jo, Kwang-Wook; Shin, Hyung Jin; Nam, Do-Hyun; Lee, Jung-Il; Park, Kwan; Kim, Jong Hyun; Kong, Doo-Sik

    2011-10-01

    Surgery for deep-seated brain lesions without causing significant trauma to the overlying cortex is difficult because brain retraction is required to approach these lesions. The aim of this study was to determine the efficacy of endoport-guided endoscopic or microscopic removal for deep-seated lesions using the neuronavigation system. Between October 2008 and December 2009, 21 patients (17 men and 4 women; average age, 40.8 years) underwent endoport-guided endoscopic tumor removal. We adapted the transparent tubular conduit, so-called "endoport," to target the lesions under the guidance of neuronavigation. We then determined the efficacy and limitations of this technique with fully endoscopic removal, compared with standard approaches using a spatula retractor. Gross total resection of the lesions was achieved in 14 of 21 patients (66%), and partial removal occurred in four (19%) patients. However, there was failure to remove the lesion through the endoport in three patients (14.3%), requiring the use of blade spatula retractors. In reviewing the seven cases with either failure or partial removal, it was found that a large tumor size (≥ 3 cm) and calcified lesions were the major factors limiting the application of this technique. Endoport-guided endoscopic surgery facilitated an accurate and minimally invasive technique for removal of these deep-seated brain lesions. This procedure required a protracted learning curve although, when successful, this approach can minimize brain retraction and provide satisfactory visualization. PMID:21614427

  3. Emerging new trends in neurosurgical technologies.

    PubMed

    Zhang, Yang; Zhao, Dongxu; Li, Hongyan; Li, Ye; Zhu, Xiaobo; Zhang, Xiaona

    2014-09-01

    There has been tremendous progress in the modern day technologies causing a rapid evolution in the field of neurosurgery. The neurosurgeons have been equipped with the latest advancements such as the use of robotics in surgery, the image-guided neurosurgical procedures, and the stereotactic neurosurgery. In addition, the preoperative screening techniques have drastically improved the success of the surgical procedure. Neuronavigation has allowed the precise localization of the deep-seated brain structures thereby helping in the accurate operation of the affected regions without stirring the normal brain tissues. Such preciseness has helped in the improvement of the patient outcome. All these aspects have been discussed in detail in this review with a focus on their developmental background. PMID:24639108

  4. Minimally invasive endoscopic surgery for treatment of spontaneous intracerebral haematomas.

    PubMed

    Beynon, Christopher; Schiebel, Patrick; Bösel, Julian; Unterberg, Andreas W; Orakcioglu, Berk

    2015-07-01

    Spontaneous intracerebral haemorrhage (ICH) is a devastating disease with a mortality rate of more than 40 % and a high morbidity rate with 10-15 % of survivors remaining fully dependent [11]. The role of surgical treatment of ICH remains a matter of controversy and ongoing investigation. Advances in neurosurgical techniques such as endoscopy and neuronavigation have been established in various fields of neurosurgery. Results of reported case series have suggested that some patients with ICH may benefit from haematoma evacuation through minimally invasive endoscopic procedures. In this article, we focus on the pathophysiologic rationales behind minimally invasive haematoma evacuation through endoscopic surgery and provide an overview of technical developments and reported patient series. In addition, the modalities of the surgical procedure at the authors' institution are described. Controlled clinical trials are needed to evaluate the full potential and limitations of this promising technique. PMID:25687253

  5. Percutaneous ultrasound-guided insertion of ventriculo-atrial shunts.

    PubMed

    McCracken, James Albert; Bahl, Anuj; McMullan, John

    2016-08-01

    Ventriculo-atrial (VA) shunts have been in use for >60 years but less frequently so of late. This is due to a combination of the risk of cardiac complications, lack of expertise and a lengthy operation. We present our consecutive prospective series of 10 VA shunts inserted using a percutaneous method employing the Sonowand Invite™ neuronavigation system for both the distal and proximal catheters, over a 13-month period. We had two complications of cases needing revision, but our series highlights a safe and reproducible method of inserting a VA shunt. About 30% of the procedures were carried out by a trainee as the primary surgeon. This technique does not necessarily require the expertise of a complex hydrocephalus surgeon and is thus able to be in the armoury of any neurosurgeon needing to do a VA shunt procedure. The indications, operative data and outcomes of our patients are discussed. PMID:27025913

  6. A single burr hole approach for direct transverse sinus cannulation for the treatment of a dural arteriovenous fistula

    PubMed Central

    Caplan, Justin M; Kaminsky, Ian; Gailloud, Philippe; Huang, Judy

    2014-01-01

    A 55-year-old woman with a symptomatic Borden II/Cognard IIa+b transverse sinus dural arteriovenous fistula underwent an attempted percutaneous transvenous embolization which was ultimately not possible given the fistula anatomy. She then underwent a partial percutaneous transarterial embolization but the fistula recurred. Given the failed percutaneous interventions, the patient underwent a combined open surgical/transvenous embolization using neuronavigation and a single burr hole craniectomy. She has remained symptom free for 3 months. This case report illustrates the feasibility of combining minimally invasive open surgical access to allow for direct venous cannulation for endovascular embolization of a dural arteriovenous fistula when traditional percutaneous methods are not an option. PMID:24398868

  7. Serial FEM/XFEM-Based Update of Preoperative Brain Images Using Intraoperative MRI

    PubMed Central

    Vigneron, Lara M.; Noels, Ludovic; Warfield, Simon K.; Verly, Jacques G.; Robe, Pierre A.

    2012-01-01

    Current neuronavigation systems cannot adapt to changing intraoperative conditions over time. To overcome this limitation, we present an experimental end-to-end system capable of updating 3D preoperative images in the presence of brain shift and successive resections. The heart of our system is a nonrigid registration technique using a biomechanical model, driven by the deformations of key surfaces tracked in successive intraoperative images. The biomechanical model is deformed using FEM or XFEM, depending on the type of deformation under consideration, namely, brain shift or resection. We describe the operation of our system on two patient cases, each comprising five intraoperative MR images, and we demonstrate that our approach significantly improves the alignment of nonrigidly registered images. PMID:22287953

  8. Occipital neuralgia secondary to unilateral atlantoaxial osteoarthritis: Case report and review of the literature

    PubMed Central

    Guha, Daipayan; Mohanty, Chandan; Tator, Charles H.; Shamji, Mohammed F.

    2015-01-01

    Background: Atlantoaxial osteoarthritis (AAOA), either in isolation or in the context of generalized peripheral or spinal arthritis, presents most commonly with neck pain and limitation of cervical rotational range of motion. Occipital neuralgia (ON) is only rarely attributed to AAOA, as fewer than 30 cases are described in the literature. Case Description: A 64-year-old female presented with progressive incapacitating cervicalgia and occipital headaches, refractory to medications, and local anesthetic blocks. Computed tomography and magnetic resonance imaging studies documented advanced unilateral atlantoaxial arthrosis with osteophytic compression that dorsally displaced the associated C2 nerve root. Surgical decompression and atlantoaxial fusion achieved rapid and complete relief of neuralgia. Ultimately, postoperative spinal imaging revealed osseous union. Conclusions: Atlantoaxial arthrosis must be considered in the differential diagnosis of ON. Surgical treatment is effective for managing refractory cases. Intraoperative neuronavigation is also a useful adjunct to guide instrumentation and the intraoperative extent of bony decompression. PMID:26759731

  9. Frontal lobe epilepsy with atypical seizure semiology resembling shuddering attacks or wet dog shake seizures.

    PubMed

    Jahodova, Alena; Krsek, Pavel; Komarek, Vladimir; Kudr, Martin; Kyncl, Martin; Zamecnik, Josef; Tichy, Michal

    2012-03-01

    We report a girl with a drug-resistant frontal lobe epilepsy caused by focal cortical dysplasia, who exhibited uncommon seizures. The seizures consisted of shoulder or whole body shuddering after a short psychic aura and face grimacing. Consciousness was fully preserved. The seizures resembled "wet dog shake" seizures described in rat models of epilepsy or shuddering attacks in infants. EEG findings were inconclusive, however, MRI showed a clear dysplastic lesion in the right frontal mesial and polar structures. The patient underwent an extended lesionectomy guided by neuronavigation and intraoperative electrocorticography. Focal cortical dysplasia type Ib was histologically confirmed and the patient has been seizure-free for the three years following resection. [Published with video sequences]. PMID:22425715

  10. Successful Treatment of Phantom Limb Pain by 1 Hz Repetitive Transcranial Magnetic Stimulation Over Affected Supplementary Motor Complex: A Case Report

    PubMed Central

    Lee, Jong-Hoo; Byun, Jeong-Hyun; Choe, Yu-Ri; Lim, Seung-Kyu; Lee, Ka-Young

    2015-01-01

    A 37-year-old man with a right transfemoral amputation suffered from severe phantom limb pain (PLP). After targeting the affected supplementary motor complex (SMC) or primary motor cortex (PMC) using a neuro-navigation system with 800 stimuli of 1 Hz repetitive transcranial magnetic stimulation (rTMS) at 85% of resting motor threshold, the 1 Hz rTMS over SMC dramatically reduced his visual analog scale (VAS) of PLP from 7 to 0. However, the 1 Hz rTMS over PMC failed to reduce pain. To our knowledge, this is the first case report of a successfully treated severe PLP with a low frequency rTMS over SMC in affected hemisphere. PMID:26361601

  11. Successful Treatment of Phantom Limb Pain by 1 Hz Repetitive Transcranial Magnetic Stimulation Over Affected Supplementary Motor Complex: A Case Report.

    PubMed

    Lee, Jong-Hoo; Byun, Jeong-Hyun; Choe, Yu-Ri; Lim, Seung-Kyu; Lee, Ka-Young; Choi, In-Sung

    2015-08-01

    A 37-year-old man with a right transfemoral amputation suffered from severe phantom limb pain (PLP). After targeting the affected supplementary motor complex (SMC) or primary motor cortex (PMC) using a neuro-navigation system with 800 stimuli of 1 Hz repetitive transcranial magnetic stimulation (rTMS) at 85% of resting motor threshold, the 1 Hz rTMS over SMC dramatically reduced his visual analog scale (VAS) of PLP from 7 to 0. However, the 1 Hz rTMS over PMC failed to reduce pain. To our knowledge, this is the first case report of a successfully treated severe PLP with a low frequency rTMS over SMC in affected hemisphere. PMID:26361601

  12. Estimation of intra-operative brain shift based on constrained Kalman filter.

    PubMed

    Shakarami, M; Suratgar, A A; Talebi, H A

    2015-03-01

    In this study, the problem of estimation of brain shift is addressed by which the accuracy of neuronavigation systems can be improved. To this end, the actual brain shift is considered as a Gaussian random vector with a known mean and an unknown covariance. Then, brain surface imaging is employed together with solutions of linear elastic model and the best estimation is found using constrained Kalman filter (CKF). Moreover, a recursive method (RCKF) is presented, the computational cost of which in the operating room is significantly lower than CKF, because it is not required to compute inverse of any large matrix. Finally, the theory is verified by the simulation results, which show the superiority of the proposed method as compared to one existing method. PMID:25451818

  13. Indocyanine Green Fluorescence Endoscopy at Endonasal Transsphenoidal Surgery for an Intracavernous Sinus Dermoid Cyst: Case Report

    PubMed Central

    HIDE, Takuichiro; YANO, Shigetoshi; KURATSU, Jun-ichi

    2014-01-01

    The complete resection of intracavernous sinus dermoid cysts is very difficult due to tumor tissue adherence to important anatomical structures such as the internal carotid artery (ICA), cavernous sinus, and cranial nerves. As residual dermoid cyst tissue sometimes induces symptoms and repeat surgery may be required after cyst recurrence, minimal invasiveness is an important consideration when selecting the surgical approach to the lesion. We addressed a recurrent intracavernous sinus dermoid cyst by the endoscopic endonasal transsphenoidal approach assisted by neuronavigation and indocyanine green (ICG) endoscopy to confirm the ICA and patency of the cavernous sinus. The ICG endoscope detected the fluorescence signal from the ICA and cavernous sinus; its intensity changed with the passage of time. The ICG endoscope was very useful for real-time imaging, and its high spatial resolution facilitated the detection of the ICA and the patent cavernous sinus. We found it to be of great value for successful endonasal transsphenoidal surgery. PMID:25446381

  14. Subcortical mapping of calculation processing in the right parietal lobe.

    PubMed

    Della Puppa, Alessandro; De Pellegrin, Serena; Lazzarini, Anna; Gioffrè, Giorgio; Rustemi, Oriela; Cagnin, Annachiara; Scienza, Renato; Semenza, Carlo

    2015-05-01

    Preservation of calculation processing in brain surgery is crucial for patients' quality of life. Over the last decade, surgical electrostimulation was used to identify and preserve the cortical areas involved in such processing. Conversely, subcortical connectivity among different areas implicated in this function remains unclear, and the role of surgery in this domain has not been explored so far. The authors present the first 2 cases in which the subcortical functional sites involved in calculation were identified during right parietal lobe surgery. Two patients affected by a glioma located in the right parietal lobe underwent surgery with the aid of MRI neuronavigation. No calculation deficits were detected during preoperative assessment. Cortical and subcortical mapping were performed using a bipolar stimulator. The current intensity was determined by progressively increasing the amplitude by 0.5-mA increments (from a baseline of 1 mA) until a sensorimotor response was elicited. Then, addition and multiplication calculation tasks were administered. Corticectomy was performed according to both the MRI neuronavigation data and the functional findings obtained through cortical mapping. Direct subcortical electrostimulation was repeatedly performed during tumor resection. Subcortical functional sites for multiplication and addition were detected in both patients. Electrostimulation interfered with calculation processing during cortical mapping as well. Functional sites were spared during tumor removal. The postoperative course was uneventful, and calculation processing was preserved. Postoperative MRI showed complete resection of the tumor. The present preliminary study shows for the first time how functional mapping can be a promising method to intraoperatively identify the subcortical functional sites involved in calculation processing. This report therefore supports direct electrical stimulation as a promising tool to improve the current knowledge on

  15. Multimodal navigated skull base tumor resection using image-based vascular and cranial nerve segmentation: A prospective pilot study

    PubMed Central

    Dolati, Parviz; Gokoglu, Abdulkerim; Eichberg, Daniel; Zamani, Amir; Golby, Alexandra; Al-Mefty, Ossama

    2015-01-01

    Background: Skull base tumors frequently encase or invade adjacent normal neurovascular structures. For this reason, optimal tumor resection with incomplete knowledge of patient anatomy remains a challenge. Methods: To determine the accuracy and utility of image-based preoperative segmentation in skull base tumor resections, we performed a prospective study. Ten patients with skull base tumors underwent preoperative 3T magnetic resonance imaging, which included thin section three-dimensional (3D) space T2, 3D time of flight, and magnetization-prepared rapid acquisition gradient echo sequences. Imaging sequences were loaded in the neuronavigation system for segmentation and preoperative planning. Five different neurovascular landmarks were identified in each case and measured for accuracy using the neuronavigation system. Each segmented neurovascular element was validated by manual placement of the navigation probe, and errors of localization were measured. Results: Strong correspondence between image-based segmentation and microscopic view was found at the surface of the tumor and tumor-normal brain interfaces in all cases. The accuracy of the measurements was 0.45 ± 0.21 mm (mean ± standard deviation). This information reassured the surgeon and prevented vascular injury intraoperatively. Preoperative segmentation of the related cranial nerves was possible in 80% of cases and helped the surgeon localize involved cranial nerves in all cases. Conclusion: Image-based preoperative vascular and neural element segmentation with 3D reconstruction is highly informative preoperatively and could increase the vigilance of neurosurgeons for preventing neurovascular injury during skull base surgeries. Additionally, the accuracy found in this study is superior to previously reported measurements. This novel preliminary study is encouraging for future validation with larger numbers of patients. PMID:26674155

  16. Metabolic approach for tumor delineation in glioma surgery: 3D MR spectroscopy image-guided resection.

    PubMed

    Zhang, Jie; Zhuang, Dong-Xiao; Yao, Cheng-Jun; Lin, Ching-Po; Wang, Tian-Liang; Qin, Zhi-Yong; Wu, Jin-Song

    2016-06-01

    OBJECT The extent of resection is one of the most essential factors that influence the outcomes of glioma resection. However, conventional structural imaging has failed to accurately delineate glioma margins because of tumor cell infiltration. Three-dimensional proton MR spectroscopy ((1)H-MRS) can provide metabolic information and has been used in preoperative tumor differentiation, grading, and radiotherapy planning. Resection based on glioma metabolism information may provide for a more extensive resection and yield better outcomes for glioma patients. In this study, the authors attempt to integrate 3D (1)H-MRS into neuronavigation and assess the feasibility and validity of metabolically based glioma resection. METHODS Choline (Cho)-N-acetylaspartate (NAA) index (CNI) maps were calculated and integrated into neuronavigation. The CNI thresholds were quantitatively analyzed and compared with structural MRI studies. Glioma resections were performed under 3D (1)H-MRS guidance. Volumetric analyses were performed for metabolic and structural images from a low-grade glioma (LGG) group and high-grade glioma (HGG) group. Magnetic resonance imaging and neurological assessments were performed immediately after surgery and 1 year after tumor resection. RESULTS Fifteen eligible patients with primary cerebral gliomas were included in this study. Three-dimensional (1)H-MRS maps were successfully coregistered with structural images and integrated into navigational system. Volumetric analyses showed that the differences between the metabolic volumes with different CNI thresholds were statistically significant (p < 0.05). For the LGG group, the differences between the structural and the metabolic volumes with CNI thresholds of 0.5 and 1.5 were statistically significant (p = 0.0005 and 0.0129, respectively). For the HGG group, the differences between the structural and metabolic volumes with CNI thresholds of 0.5 and 1.0 were statistically significant (p = 0.0027 and 0

  17. Orbit-associated tumors: navigation and control of resection using intraoperative computed tomography.

    PubMed

    Terpolilli, Nicole A; Rachinger, Walter; Kunz, Mathias; Thon, Niklas; Flatz, Wilhelm H; Tonn, Jörg-Christian; Schichor, Christian

    2016-05-01

    OBJECT Treatment of skull base lesions is complex and usually requires a multidisciplinary approach. In meningioma, which is the most common tumor entity in this region, resection is considered to be the most important therapeutic step to avoid tumor recurrence. However, resection of skull base lesions with orbital or optic nerve involvement poses a challenge due to their anatomical structure and their proximity to eloquent areas. Therefore the main goal of surgery should be to achieve the maximum extent of resection while preserving neurological function. In the postoperative course, medical and radiotherapeutic strategies may then be successfully used to treat possible tumor residues. Methods to safely improve the extent of resection in skull base lesions therefore are desirable. The current study reports the authors' experience with the use of intraoperative CT (iCT) combined with neuronavigation with regard to feasibility and possible benefits of the method. METHODS Those patients with tumorous lesions in relationship to the orbit, sphenoid wing, or cavernous sinus who were surgically treated between October 2008 and December 2013 using iCT-based neuronavigation and in whom an intraoperative scan was obtained for control of resection were included. In all cases a second iCT scan was performed under sterile conditions after completion of navigation-guided microsurgical tumor resection. The surgical strategy was adapted accordingly; if necessary, resection was continued. RESULTS Twenty-three patients (19 with WHO Grade I meningioma and 4 with other lesions) were included. The most common clinical symptoms were loss of visual acuity and exophthalmus. Intraoperative control of resection by iCT was successfully obtained in all cases. Intraoperative imaging changed the surgical approach in more than half (52.2%) of these patients, either because iCT demonstrated unexpected residual tumor masses or because the second scan revealed additional tumor tissue that was not

  18. Occipital condyle to cervical spine fixation in the pediatric population.

    PubMed

    Kosnik-Infinger, Libby; Glazier, Steven S; Frankel, Bruce M

    2014-01-01

    Fixation at the craniovertebral junction (CVJ) is necessary in a variety of pediatric clinical scenarios. Traditionally an occipital bone to cervical fusion is preformed, which requires a large amount of hardware to be placed on the occiput of a child. If a patient has previously undergone a posterior fossa decompression or requires a decompression at the time of the fusion procedure, it can be difficult to anchor a plate to the occipital bone. The authors propose a technique that can be used when faced with this difficult challenge by using the occipital condyle as a point of fixation for the construct. Adult cadaveric and a limited number of case studies have been published using occipital condyle (C-0) fixation. This work was adapted for the pediatric population. Between 2009 and 2012, 4 children underwent occipital condyle to axial or subaxial spine fixation. One patient had previously undergone posterior fossa surgery for tumor resection, and 1 required decompression at the time of operation. Two patients underwent preoperative deformity reduction using traction. One child had a Chiari malformation Type I. Each procedure was performed using polyaxial screw-rod constructs with intraoperative neuronavigation supplemented by a custom navigational drill guide. Smooth-shanked 3.5-mm polyaxial screws, ranging in length from 26 to 32 mm, were placed into the occipital condyles. All patients successfully underwent occipital condyle to cervical spine fixation. In 3 patients the construct extended from C-0 to C-2, and in 1 from C-0 to T-2. Patients with preoperative halo stabilization were placed in a cervical collar postoperatively. There were no new postoperative neurological deficits or vascular injuries. Each patient underwent postoperative CT, demonstrating excellent screw placement and evidence of solid fusion. Occipital condyle fixation is an effective option in pediatric patients requiring occipitocervical fusion for treatment of deformity and/or instability at

  19. Neural networks improve brain cancer detection with Raman spectroscopy in the presence of light artifacts

    NASA Astrophysics Data System (ADS)

    Jermyn, Michael; Desroches, Joannie; Mercier, Jeanne; St-Arnaud, Karl; Guiot, Marie-Christine; Petrecca, Kevin; Leblond, Frederic

    2016-03-01

    It is often difficult to identify cancer tissue during brain cancer (glioma) surgery. Gliomas invade into areas of normal brain, and this cancer invasion is frequently not detected using standard preoperative magnetic resonance imaging (MRI). This results in enduring invasive cancer following surgery and leads to recurrence. A hand-held Raman spectroscopy is able to rapidly detect cancer invasion in patients with grade 2-4 gliomas. However, ambient light sources can produce spectral artifacts which inhibit the ability to distinguish between cancer and normal tissue using the spectral information available. To address this issue, we have demonstrated that artificial neural networks (ANN) can accurately classify invasive cancer versus normal brain tissue, even when including measurements with significant spectral artifacts from external light sources. The non-parametric and adaptive model used by ANN makes it suitable for detecting complex non-linear spectral characteristics associated with different tissues and the confounding presence of light artifacts. The use of ANN for brain cancer detection with Raman spectroscopy, in the presence of light artifacts, improves the robustness and clinical translation potential for intraoperative use. Integration with the neurosurgical workflow is facilitated by accounting for the effect of light artifacts which may occur, due to operating room lights, neuronavigation systems, windows, or other light sources. The ability to rapidly detect invasive brain cancer under these conditions may reduce residual cancer remaining after surgery, and thereby improve patient survival.

  20. Repetitive Transcranial Magnetic Stimulation to Supplementary Motor Area in Refractory Obsessive-Compulsive Disorder Treatment: a Sham-Controlled Trial

    PubMed Central

    Harika-Germaneau, Ghina; Rachid, Fady; Gaudeau-Bosma, Christian; Tanguy, Marie-Laure; BenAdhira, Rene; Bouaziz, Noomane; Popa, Traian; Wassouf, Issa; Saba, Ghassen; Januel, Dominique; Jaafari, Nematollah

    2016-01-01

    Background: Repetitive transcranial magnetic stimulation has been explored in patients with obsessive-compulsive disorder, but with negative or conflicting results. This randomized double-blind study was designed to assess the efficacy of 1-Hz repetitive transcranial magnetic stimulation over the presupplementary area. Methods: Forty medication-resistant patients were assigned to 4 weeks of either active or sham repetitive transcranial magnetic stimulation targeting the presupplementary area with the help of a neuronavigation system. Results: According to the Yale-Brown obsessive-compulsive scale, the baseline-week 4 evolution showed no significant differences between groups. Responder rates at week 4 were not different between groups (repetitive transcranial magnetic stimulation 10.5% vs sham 20%; P=.63). Conclusion: Low-frequency repetitive transcranial magnetic stimulation applied to the presupplementary area seems ineffective for the treatment of obsessive-compulsive disorder patients, at least in severe and drug-refractory cases such as those included in this study. Further research is required to determine profiles of responder patients and appropriate repetitive transcranial magnetic stimulation parameters for obsessive-compulsive disorder. PMID:27207923

  1. [Results of radical removal of malignant cerebral gliomas, by using computer-assisted navigation, followed by adjuvant therapy].

    PubMed

    Krivoshapkin, A L; Kanygin, V V; Semin, P A; Melidi, E G

    2006-01-01

    A retrospective cohort analysis of the results of treatment of patients with malignant gliomas was made in 2 groups, each comprising 43 patients. In Group 1, the tumors were radically removed under neuronavigation guidance ("Voyager SX"). In Group 2 where the patients were operated on by the same team of surgeons who did not employ computer-assisted navigation technologies. The results of different adjuvant therapy regimens were analyzed in patients after radical tumor removal under navigation guidance (Group 1). In its first subgroup, 24 patients with anaplastic astrocytes were postoperatively irradiated (60 Gy), followed by treatment with temodal (200 mg/m2 (mean 6 courses). In the second subgroup, 12 patients received chemoradiotherapy (temodal, 75 mg/m2 daily + irradiation), followed by courses (n=6) of temodal, 200 mg/m2). In the third subgroup, 7 patients were treated with fotemustin (200 mg/m2 (induction) + 5 cycles). The computer-assisted technologies substantially improve a postoperative outcome in patients with malignant glionas. Current chemoradiotherapy is relatively safe and prolongs a relapse-free interval with a high quality of life. Further studies call for the efficiency of different adjuvant therapy regimens after radical surgery. PMID:17195370

  2. Susceptibility artefact correction using dynamic graph cuts: application to neurosurgery.

    PubMed

    Daga, Pankaj; Pendse, Tejas; Modat, Marc; White, Mark; Mancini, Laura; Winston, Gavin P; McEvoy, Andrew W; Thornton, John; Yousry, Tarek; Drobnjak, Ivana; Duncan, John S; Ourselin, Sebastien

    2014-10-01

    Echo Planar Imaging (EPI) is routinely used in diffusion and functional MR imaging due to its rapid acquisition time. However, the long readout period makes it prone to susceptibility artefacts which results in geometric and intensity distortions of the acquired image. The use of these distorted images for neuronavigation hampers the effectiveness of image-guided surgery systems as critical white matter tracts and functionally eloquent brain areas cannot be accurately localised. In this paper, we present a novel method for correction of distortions arising from susceptibility artefacts in EPI images. The proposed method combines fieldmap and image registration based correction techniques in a unified framework. A phase unwrapping algorithm is presented that can efficiently compute the B0 magnetic field inhomogeneity map as well as the uncertainty associated with the estimated solution through the use of dynamic graph cuts. This information is fed to a subsequent image registration step to further refine the results in areas with high uncertainty. This work has been integrated into the surgical workflow at the National Hospital for Neurology and Neurosurgery and its effectiveness in correcting for geometric distortions due to susceptibility artefacts is demonstrated on EPI images acquired with an interventional MRI scanner during neurosurgery. PMID:25047865

  3. Preoperative or preembolization lesion targeting using rotational angiographic fiducial marking in the neuroendovascular suite.

    PubMed

    Lim, Siok Ping; Lesiuk, Howard; Sinclair, John; Lum, Cheemun

    2011-01-01

    Three-dimensional rotational digital subtraction (DS) angiography and DynaCT allow precise localization of intracranial arteriovenous fistulas (AVFs) with fiducial markers that have helped in surgical planning. These techniques are particularly useful when the AVF is not evident on cross-sectional imaging. The authors demonstrate the utility of 3D DS angiography and DynaCT in the localization of intracranial AVFs in 3 cases. Their first case was a dural AVF with multiple arterial feeders from the left occipital artery that drained into the left transverse sinus. Blood flow to the left transverse sinus was first decreased by embolizing the branch arterial feeders with polyvinyl alcohol particles. Thereafter, 3D DS angiography enabled precise localization of the site for the bur hole creation with a fiducial to allow access for the transverse sinus in the second part of the procedure where definitive transvenous sinus embolization of the dural AVF with coils was performed. They also used 3D DS angiography and DynaCT with fiducials for precise localization of a superficial pial AVF (Case 2) and a tentorial AVF (Case 3) not visible on cross-sectional angiography. With the precise localization of the target lesion, the neurosurgeons were able to perform relatively small craniotomies, minimizing the cranial opening yet allowing the opening for full access to the lesion. By correlating 3D DS angiography/DynaCT with CT images, the neurosurgeon could use neuronavigation in cases of AVF not appreciated on cross-sectional imaging. PMID:20170306

  4. Supra-complete surgery via dual intraoperative visualization approach (DiVA) prolongs patient survival in glioblastoma.

    PubMed

    Eyüpoglu, Ilker Y; Hore, Nirjhar; Merkel, Andreas; Buslei, Rolf; Buchfelder, Michael; Savaskan, Nicolai

    2016-05-01

    Safe and complete resection represents the first step in the treatment of glioblastomas and is mandatory in increasing the effectiveness of adjuvant therapy to prolong overall survival. With gross total resection currently limited in extent to MRI contrast enhancing areas, the extent to which supra-complete resection beyond obvious contrast enhancement could have impact on overall survival remains unclear. DiVA (dual intraoperative visualization approach) redefines gross total resection as currently accepted by enabling for the first time supra-complete surgery without compromising patient safety. This approach exploits the advantages of two already accepted surgical techniques combining intraoperative MRI with integrated functional neuronavigation and 5-ALA by integrating them into a single surgical approach. We investigated whether this technique has impact on overall outcome in GBM patients. 105 patients with GBM were included. We achieved complete resection with intraoperative MRI alone according to current best-practice in glioma surgery in 75 patients. 30 patients received surgery with supra-complete resection. The control arm showed a median life expectancy of 14 months, reflecting current standards-of-care and outcome. In contrast, patients receiving supra-complete surgery displayed significant increase in median survival time to 18.5 months with overall survival time correlating directly with extent of supra-complete resection. This extension of overall survival did not come at the cost of neurological deterioration. We show for the first time that supra-complete glioma surgery leads to significant prolongation of overall survival time in GBM patients. PMID:27036027

  5. A Pipeline for 3D Multimodality Image Integration and Computer-assisted Planning in Epilepsy Surgery.

    PubMed

    Nowell, Mark; Rodionov, Roman; Zombori, Gergely; Sparks, Rachel; Rizzi, Michele; Ourselin, Sebastien; Miserocchi, Anna; McEvoy, Andrew; Duncan, John

    2016-01-01

    Epilepsy surgery is challenging and the use of 3D multimodality image integration (3DMMI) to aid presurgical planning is well-established. Multimodality image integration can be technically demanding, and is underutilised in clinical practice. We have developed a single software platform for image integration, 3D visualization and surgical planning. Here, our pipeline is described in step-by-step fashion, starting with image acquisition, proceeding through image co-registration, manual segmentation, brain and vessel extraction, 3D visualization and manual planning of stereoEEG (SEEG) implantations. With dissemination of the software this pipeline can be reproduced in other centres, allowing other groups to benefit from 3DMMI. We also describe the use of an automated, multi-trajectory planner to generate stereoEEG implantation plans. Preliminary studies suggest this is a rapid, safe and efficacious adjunct for planning SEEG implantations. Finally, a simple solution for the export of plans and models to commercial neuronavigation systems for implementation of plans in the operating theater is described. This software is a valuable tool that can support clinical decision making throughout the epilepsy surgery pathway. PMID:27286266

  6. Intraoperative Image Guidance in Neurosurgery: Development, Current Indications, and Future Trends

    PubMed Central

    Schulz, Chris; Waldeck, Stephan; Mauer, Uwe Max

    2012-01-01

    Introduction. As minimally invasive surgery becomes the standard of care in neurosurgery, it is imperative that surgeons become skilled in the use of image-guided techniques. The development of image-guided neurosurgery represents a substantial improvement in the microsurgical treatment of tumors, vascular malformations, and other intracranial lesions. Objective. There have been numerous advances in neurosurgery which have aided the neurosurgeon to achieve accurate removal of pathological tissue with minimal disruption of surrounding healthy neuronal matter including the development of microsurgical, endoscopic, and endovascular techniques. Neuronavigation systems and intraoperative imaging should improve success in cranial neurosurgery. Additional functional imaging modalities such as PET, SPECT, DTI (for fiber tracking), and fMRI can now be used in order to reduce neurological deficits resulting from surgery; however the positive long-term effect remains questionable for many indications. Method. PubMed database search using the search term “image guided neurosurgery.” More than 1400 articles were published during the last 25 years. The abstracts were scanned for prospective comparative trials. Results and Conclusion. 14 comparative trials are published. To date significant data amount show advantages in intraoperative accuracy influencing the perioperative morbidity and long-term outcome only for cerebral glioma surgery. PMID:22655196

  7. Endoscopic pituitary surgery: Techniques, tips and tricks, nuances, and complication avoidance.

    PubMed

    Sharma, Bhawani Shanker; Sawarkar, Dattaraj Paramanand; Suri, Ashish

    2016-01-01

    Endoscopic pituitary surgery is useful in all micro- and macro-pituitary adenomas including those with suprasellar and cavernous sinus extension. The endoscope provides a panoramic close-up, a multi-angled view with excellent illumination and magnification, permitting complete excision of the tumor with preservation of normal pituitary. However, surgeons need to learn altogether different skills unique to endoscopy and the learning curve is steep. The learning curve can be shortened by proper selection of cases, gradual transition from the microscopic to the endoscopic approach, adequate sphenoethmoidal recess widening, identification of important landmarks during each stage of surgery, and use of neuronavigation. Results and long term outcomes can be improved with bimanual dynamic dissection and sequential tumor excision, preservation of normal pituitary, avoidance of arachnoidal tear and use of extended approach for tumors with large suprasellar extension. The gradual transition from microscopic to endoscopic approach, adherence to step by step technique and learning 'tips and tricks' of the endoscopic pituitary surgery reduce complications. PMID:27381121

  8. Establishment of a Comprehensive Epilepsy Center in Pakistan: Initial Experiences, Results, and Reflections

    PubMed Central

    Tahir, M. Zubair; Sobani, Zain A.; Quadri, S. A.; Ahmed, S. Nizam; Sheerani, Mughis; Siddiqui, Fowzia; Boling, Warren W.; Enam, Syed Ather

    2012-01-01

    Background. Developing countries, home to 80% of epilepsy patients, do not have comprehensive epilepsy surgery programs. Considering these needs we set up first epilepsy surgery center in Pakistan. Methods. Seventeen teleconferences focused on setting up an epilepsy center at the Aga Khan University (AKU), Karachi, Pakistan were arranged with experts from the University of Alberta Hospital, Alberta, Canada and the University of West Virginia, USA over a two-year period. Subsequently, the experts visited the proposed center to provide hands on training. During this period several interactive teaching sessions, a nationwide workshop, and various public awareness events were organized. Results. Sixteen patients underwent surgery, functional hemispherectomy (HS) was done in six, anterior temporal lobectomy (ATL) in six, and neuronavigation-guided selective amygdalohippocampectomy (SAH) using keyhole technique in four patients. Minimal morbidity was observed in ATL and, SAH groups. All patients in SAH group (100%) had Grade 1 control, while only 5 patients (83%) in ATL group, and 4 patients (66%) in HS group had Grade 1 control according to Engel's classification, in average followups of 12 months, 24 months and 48 months for SAH, ATL, and HS, respectively. Conclusion. As we share our experience we hope to set a practical example for economically constrained countries that successful epilepsy surgery centers can be managed with limited resources. PMID:22957232

  9. A critical analysis of the current state of neurosurgery training in Pakistan

    PubMed Central

    Shamim, M. Shahzad; Tahir, M. Zubair; Godil, Saniya Siraj; Kumar, Rajesh; Siddiqui, Arshad Ali

    2011-01-01

    Objective: To observe interdepartmental variation in the availability of resources and academic activities within the various neurosurgery programs of Pakistan. Methods: This was a proforma-based survey of neurosurgery trainees and young neurosurgeons of Pakistan, looking at the academic infrastructure and output of their programs. The proforma was filled by 36 respondents from 11 neurosurgery centers of the country. All these centers were accredited for neurosurgery training in Pakistan. Results: Out of the 36 respondents, 30 were completing a Fellowship training (FCPS) and six were enrolled for a Master in Surgery (MS) program. About 80% of the participants used the Youman's Textbook of Neurosurgery as a reference book. Only 40% of the candidates had access to more than one indexed neurosurgery journal. Structured academic sessions (e.g., journal clubs and neuropathology meetings) were lacking in a majority of the training institutes, 95% of the trainees had no microsurgical laboratory experience, and modern neurosurgical tools (frameless neuronavigation system, neuroendoscopy) were in use at a few centers only. Conclusion: Neurosurgery training in Pakistan is not uniform and wide variations exist between the programs at the centers evaluated. We recommend exchange programs between centers at national and international levels, to allow trainees to gain first-hand exposure to training components not available in their own center. PMID:22276237

  10. Model-based brain shift compensation in image-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Ji, Songbai; Liu, Fenghong; Fan, Xiaoyao; Hartov, Alex; Roberts, David; Paulsen, Keith

    2009-02-01

    Intraoperative brain shift compensation is important for improving the accuracy of neuronavigational systems and ultimately, the accuracy of brain tumor resection as well as patient quality of life. Biomechanical models are practical methods for brain shift compensation in the operating room (OR). These methods assimilate incomplete deformation data on the brain acquired from intraoperative imaging techniques (e.g., ultrasound and stereovision), and simulate whole-brain deformation under loading and boundary conditions in the OR. Preoperative images of the patient's head (e.g., preoperative magnetic resonance images (pMR)) are then deformed accordingly based on the computed displacement field to generate updated visualizations for subsequent surgical guidance. Apparently, the clinical feasibility of the technique depends on the efficiency as well as the accuracy of the computational scheme. In this paper, we identify the major steps involved in biomechanical simulation of whole-brain deformation and demonstrate the efficiency and accuracy of each step. We show that a combined computational cost of 5 minutes with an accuracy of 1-2 millimeter can be achieved which suggests that the technique is feasible for routine application in the OR.

  11. Mutual-information-corrected tumor displacement using intraoperative ultrasound for brain shift compensation in image-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Ji, Songbai; Hartov, Alex; Roberts, David; Paulsen, Keith

    2008-03-01

    Intraoperative ultrasound (iUS) has emerged as a practical neuronavigational tool for brain shift compensation in image-guided tumor resection surgeries. The use of iUS is optimized when coregistered with preoperative magnetic resonance images (pMR) of the patient's head. However, the fiducial-based registration alone does not necessarily optimize the alignment of internal anatomical structures deep in the brain (e.g., tumor) between iUS and pMR. In this paper, we investigated and evaluated an image-based re-registration scheme to maximize the normalized mutual information (nMI) between iUS and pMR to improve tumor boundary alignment using the fiducial registration as a starting point for optimization. We show that this scheme significantly (p<<0.001) reduces tumor boundary misalignment pre-durotomy. The same technique was employed to measure tumor displacement post-durotomy, and the locally measured tumor displacement was assimilated into a biomechanical model to estimate whole-brain deformation. Our results demonstrate that the nMI re-registration pre-durotomy is critical for obtaining accurate measurement of tumor displacement, which significantly improved model response at the craniotomy when compared with stereopsis data acquired independently from the tumor registration. This automatic and computationally efficient (<2min) re-registration technique is feasible for routine clinical use in the operating room (OR).

  12. Ambient mass spectrometry for the intraoperative molecular diagnosis of human brain tumors.

    PubMed

    Eberlin, Livia S; Norton, Isaiah; Orringer, Daniel; Dunn, Ian F; Liu, Xiaohui; Ide, Jennifer L; Jarmusch, Alan K; Ligon, Keith L; Jolesz, Ferenc A; Golby, Alexandra J; Santagata, Sandro; Agar, Nathalie Y R; Cooks, R Graham

    2013-01-29

    The main goal of brain tumor surgery is to maximize tumor resection while preserving brain function. However, existing imaging and surgical techniques do not offer the molecular information needed to delineate tumor boundaries. We have developed a system to rapidly analyze and classify brain tumors based on lipid information acquired by desorption electrospray ionization mass spectrometry (DESI-MS). In this study, a classifier was built to discriminate gliomas and meningiomas based on 36 glioma and 19 meningioma samples. The classifier was tested and results were validated for intraoperative use by analyzing and diagnosing tissue sections from 32 surgical specimens obtained from five research subjects who underwent brain tumor resection. The samples analyzed included oligodendroglioma, astrocytoma, and meningioma tumors of different histological grades and tumor cell concentrations. The molecular diagnosis derived from mass-spectrometry imaging corresponded to histopathology diagnosis with very few exceptions. Our work demonstrates that DESI-MS technology has the potential to identify the histology type of brain tumors. It provides information on glioma grade and, most importantly, may help define tumor margins by measuring the tumor cell concentration in a specimen. Results for stereotactically registered samples were correlated to preoperative MRI through neuronavigation, and visualized over segmented 3D MRI tumor volume reconstruction. Our findings demonstrate the potential of ambient mass spectrometry to guide brain tumor surgery by providing rapid diagnosis, and tumor margin assessment in near-real time. PMID:23300285

  13. Design optimization of the sensor spatial arrangement in a direct magnetic field-based localization system for medical applications.

    PubMed

    Marechal, Luc; Shaohui Foong; Zhenglong Sun; Wood, Kristin L

    2015-08-01

    Motivated by the need for developing a neuronavigation system to improve efficacy of intracranial surgical procedures, a localization system using passive magnetic fields for real-time monitoring of the insertion process of an external ventricular drain (EVD) catheter is conceived and developed. This system operates on the principle of measuring the static magnetic field of a magnetic marker using an array of magnetic sensors. An artificial neural network (ANN) is directly used for solving the inverse problem of magnetic dipole localization for improved efficiency and precision. As the accuracy of localization system is highly dependent on the sensor spatial location, an optimization framework, based on understanding and classification of experimental sensor characteristics as well as prior knowledge of the general trajectory of the localization pathway, for design of such sensing assemblies is described and investigated in this paper. Both optimized and non-optimized sensor configurations were experimentally evaluated and results show superior performance from the optimized configuration. While the approach presented here utilizes ventriculostomy as an illustrative platform, it can be extended to other medical applications that require localization inside the body. PMID:26736407

  14. Correlation of the CT Compatible Stereotaxic Craniotomy with MRI Scans of the Patients for Removing Cranial Lesions Located Eloquent Areas and Deep Sites of Brain

    PubMed Central

    Gulsen, Salih

    2015-01-01

    The first goal in neurosurgery is to protect neural function as long as it is possible. Moreover, while protecting the neural function, a neurosurgeon should extract the maximum amount of tumoral tissue from the tumour region of the brain. So neurosurgery and technological advancement go hand in hand to realize this goal. Using of CT compatible stereotaxy for removing a cranial tumour is to be commended as a cornerstone of these technological advancements. Following CT compatible stereotaxic system applications in neurosurgery, different techniques have taken place in neurosurgical practice. These techniques are magnetic resonance imaging (MRI), MRI compatible stereotaxis, frameless stereotaxy, volumetric stereotaxy, functional MRI, diffusion tensor (DT) imaging techniques (tractography of the white matter), intraoperative MRI and neuronavigation systems. However, to use all of this equipment having these technologies would be impossible because of economic reasons. However, when we correlated this technique with MRI scans of the patients with CT compatible stereotaxy scans, it is possible to provide gross total resection and protect and improve patients’ neural functions.

  15. Cryptococcal Brainstem Abscess Mimicking Brain Tumors in an Immunocompetent Patient

    PubMed Central

    Hur, Jong Hee; Kim, Jang-Hee; Park, Seoung Woo

    2015-01-01

    Usually fungal infections caused by opportunistic and pathogenic fungi had been an important cause of morbidity and mortality among immunocompromised patients. However clinical data and investigations for immunocompetent pathogenic fungal infections had been rare and neglected into clinical studies. Especially Cryptococcal brainstem abscess cases mimicking brain tumors were also much more rare. So we report this unusual case. This 47-year-old man presented with a history of progressively worsening headache and nausea for 1 month and several days of vomituritions before admission. Neurological and laboratory examinations performed demonstrated no abnormal findings. Previously he was healthy and did not have any significant medical illnesses. A CT and MRI scan revealed enhancing 1.8×1.7×2.0 cm mass lesion in the left pons having central necrosis and peripheral edema compressing the fourth ventricle. And also positron emission tomogram scan demonstrated a hot uptake of fluoro-deoxy-glucose on the brainstem lesion without any evidences of systemic metastasis. Gross total mass resection was achieved with lateral suboccipital approach with neuronavigation system. Postoperatively he recovered without any neurological deficits. Pathologic report confirmed Cryptococcus neoformans and he was successively treated with antifungal medications. This is a previously unreported rare case of brainstem Cryptococcal abscess mimicking brain tumors in immunocompetent host without having any apparent typical meningeal symptoms and signs with resultant good neurosurgical recovery. PMID:25674344

  16. Direct access to the middle meningeal artery for embolization of complex dural arteriovenous fistula: a hybrid treatment approach

    PubMed Central

    Lin, Ning; Brouillard, Adam M; Mokin, Maxim; Natarajan, Sabareesh K; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H

    2014-01-01

    Endovascular embolization has become increasingly favored over microsurgical resection for treatment of complex dural arteriovenous fistulas (DAVFs). However, endovascular treatment can be restricted by tortuous transarterial access and a transvenous approach is not always feasible. We present a Borden III DAVF treated by direct access to the middle meningeal artery (MMA) and Onyx embolization performed in a hybrid operating room–angiography suite. A middle-aged patient with pulsatile headaches was found to have left transverse sinus occlusion and DAVF with retrograde cortical venous drainage fed by multiple external carotid artery (ECA) feeders. Endovascular attempts via conventional transvenous and transarterial routes were unsuccessful, and the major MMA feeder was accessed directly after temporal craniotomy was performed under neuronavigation. Onyx embolization was performed; complete occlusion of the fistula was achieved. Three-month follow-up angiography showed no residual filling; the patient remains complication-free. A combined surgical–endovascular technique in a hybrid operating room–angiography suite can be an effective treatment for DAVFs complicated by inaccessible arterial and transvenous approaches. PMID:24903968

  17. A systematic review of functional magnetic resonance imaging and diffusion tensor imaging modalities used in presurgical planning of brain tumour resection.

    PubMed

    Dimou, S; Battisti, R A; Hermens, D F; Lagopoulos, J

    2013-04-01

    Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally. PMID:23187966

  18. Experimental and numerical study on the mechanical behavior of rat brain tissue.

    PubMed

    Karimi, A; Navidbakhsh, M; Yousefi, H; Haghi, A Motevalli; Sadati, Sja

    2014-02-01

    Brain tissue is a very soft tissue in which the mechanical properties depend on the loading direction. While few studies have characterized these biomechanical properties, it is worth knowing that accurate characterization of the mechanical properties of brain tissue at different loading directions is a key asset for neuronavigation and surgery simulation through haptic devices. In this study, the hyperelastic mechanical properties of rat brain tissue were measured experimentally and computationally. Prepared cylindrical samples were excised from the parietal lobes of rats' brains and experimentally tested by a tensile testing machine. The effects of loading direction on the mechanical properties of brain tissue were measured by applying load on both longitudinal and circumferential directions. The general prediction ability of the proposed hyperelastic model was verified using finite element (FE) simulations of brain tissue tension experiments. The uniaxial experimental results compared well with those predicted by the FE models. The results revealed the influence of loading direction on the mechanical properties of brain tissue. The Ogden hyperelastic material model was suitably represented by the non-linear behavior of the brain tissue, which can be used in future biomechanical simulations. The hyperelastic properties of brain tissue provided here have interest to the medical research community as there are several applications where accurate characterization of these properties are crucial for an accurate outcome, such as neurosurgery, robotic surgery, haptic device design or car manufacturing to evaluate possible trauma due to an impact. PMID:24519528

  19. Endoscopic endonasal resection of clival xanthoma: case report and literature review.

    PubMed

    González-García, Laura; Asenjo-García, Beatriz; Bautista-Ojeda, María Dolores; Domínguez-Páez, Miguel; Romero-Moreno, Lorena; Martín-Gallego, Álvaro; Arráez-Sánchez, Miguel Ángel

    2015-10-01

    Bone xanthoma is an extremely rare and benign tumor in terms of its nature and growth over time. We describe the first case coexisting with ventriculomegaly secondary to aqueduct stenosis (non-tumoral hydrocephalus), the second xanthoma of the clivus described to date. The patient was a 51-year-old woman with headaches and absence seizures. Axial T1-weighted MRI showed a well-demarcated, hypointense, osteolytic, 25 × 18 × 15 mm lesion with cortical erosion located at the right margin of the clivus. Sagittal T2-weighted MRI demonstrated a hypointense mass without associated edema. Sagittal gadolinium-enhanced T1-weighted MRI showed contrast uptake with a partially hypointense rim. The increased ventricular size without periventricular edema was associated with aqueduct stenosis, and there was no contiguity with the tumor. A neuronavigation image-guided transsphenoidal approach was chosen to perform a macroscopically complete resection. Intraoperative histopathological study showed a chordoma of the clivus. Exhaustive postsurgical study revealed the benign nature of a bone xanthoma. Given the finding of a clival lesion, the differential diagnosis is essentially with other malignant entities with a rapidly fatal outcome, such as metastases, or with a possible invasive evolution, such as clivus chordomas. This report describes the clinical, radiological, and pathological keys for such differentiation in order to avoid unnecessarily aggressive treatment with ablative surgery and radiotherapy. PMID:25820465

  20. Computerized lateral endoscopic approach to invertebral bodies

    NASA Astrophysics Data System (ADS)

    Abbasi, Hamid R.; Hariri, Sanaz; Kim, Daniel; Shahidi, Ramin; Steinberg, Gary

    2001-05-01

    Spinal surgery is often necessary to ease back pain symptoms. Neuronavigation (NN) allows the surgeon to localize the position of his instruments in 3D using pre- operative CT scans registered to intra-operative marker positions in cranial surgeries. However, this tool is unavailable in spinal surgeries for a variety of reasons. For example, because of the spine's many degrees of freedom and flexibility, the geometric relationship of the skin to the internal spinal anatomy is not fixed. Guided by the currently available imperfect 2D images, it is difficult for the surgeon to correct a patient's spinal anomaly; thus surgical relief of back pain is often only temporary. The Image Guidance Laborator's (IGL) goal is to combine the direct optical control of traditional endoscopy with the 3D orientation of NN. This powerful tool requires registration of the patient's anatomy to the surgical navigation system using internal landmarks rather than skin markers. Pre- operative CT scans matched with intraoperative fluoroscopic images can overcome the problem of spinal movement in NN registration. The combination of endoscopy with fluoroscopic registration of vertebral bodies in a NN system provides a 3D intra-operative navigational system for spinal neurosurgery to visualize the internal surgical environment from any orientation in real time. The accuracy of this system integration is being evaluated by assessing the success of nucleotomies and marker implantations guided by NN-registered endoscopy.

  1. Use of 5-ALA fluorescence guided endoscopic biopsy of a deep-seated primary malignant brain tumor.

    PubMed

    Ritz, Rainer; Feigl, Guenther C; Schuhmann, Martin U; Ehrhardt, André; Danz, Soeren; Noell, Susan; Bornemann, Antje; Tatagiba, Marcos S

    2011-05-01

    The introduction of fluorescence-guided resection of primary malignant brain tumors was a milestone in neurosurgery. Deep-seated malignant brain tumors are often not approachable for microsurgical resection. For diagnosis and therapy, new strategies are recommended. The combination of endoscopy and 5-aminolevulinic acid-induced protoporphyrin IX (5-ALA-induced Pp IX) fluorescence-guided procedures supported by neuronavigation seems an interesting option. Here the authors report on a combined approach for 5-ALA fluorescence-guided biopsy in which they use an endoscopy system based on an Xe lamp (excitation approximately λ = 407 nm; dichroic filter system λ = 380-430 nm) to treat a malignant tumor of the thalamus and perform a ventriculostomy and septostomy. The excitation filter and emission filter are adapted to ensure that the remaining visible blue remission is sufficient to superimpose on or suppress the excited red fluorescence of the endogenous fluorochromes. The authors report that the lesion was easily detectable in the fluorescence mode and that biopsy led to histological diagnosis. PMID:21166571

  2. Transcranial Clot Lysis Using High Intensity Focused Ultrasound

    NASA Astrophysics Data System (ADS)

    Hölscher, Thilo; Zadicario, Eyal; Fisher, David J.; Bradley, William G.

    2010-03-01

    Stroke is the third common cause of death worldwide. The majority of strokes are caused by sudden vessel occlusion, due to a blood clot. Vessel recanalization is the primary goal of all acute stroke treatment strategies. Initial data using ultrasound in combination with a therapeutic agent for clot lysis in stroke are promising. However, sound absorption and defocusing of the ultrasound beam occur during transskull insonation, limiting the efficiency of this approach to high extent. Using a transskull High Intensity Focused Ultrasound (HIFU) head system we were able to lyse blood clots within seconds and in absence of further lytic agents. We could show that any correction for the distortion might be negligible to focus the ultrasound beam after transskull insonation. The use of transskull HIFU for immediate clot lysis in the human brain without the need of further drugs and disregarding individual skull bone characteristics could become a successful strategy in early stroke treatment. Using magnetic resonance tomography for neuronavigation MRI Guided High Intensity Focused Ultrasound has the potential to open new avenues for therapeutic applications in the brain including Stroke, Intracranial Hemorrhages, Braintumors, Neurodegenerative Diseases, Thalamic Pain, BBB opening, and local drug delivery. First results in transcranial clot lysis will be presented in this paper.

  3. Morphological Variations in the Transverse Venous Sinus Anatomy of Dogs and its Relationship to Skull Landmarks.

    PubMed

    Carreira, L Miguel; Ferreira, A

    2016-08-01

    We characterized the anatomical morphology of the transverse venous sinus (TVS) of 69 canine adult cadavers belonging to three groups: brachycephalic (B), dolichocephalic (D) and mesaticephalic (M). In addition, we outlined its path over the skull using five classic human craniometric points (CPs): the asterion (ast), the bregma (b), the glabella (g), the stephanion (st) and the pterion (pt). The study aimed to establish anatomical differences in the TVS between groups and in the relationship between the TVS and skull. We found that TVS anatomy and its relationships to skull landmarks vary markedly between the groups, with similar anatomical arrangements in B and M. The TVS length can be ranked as M < B < D (with D being the biggest), whereas the width can be ranked as M < D < B (with B being the widest) with the right side being smaller than the left. In the B and M groups, the TVS assumes a craniocaudal trajectory that is closer to the lateral skull wall than in D, where the TVS presents a caudocranial direction. By documenting the morphological characteristics of the TVS, we can create a set of anatomical references allowing construction of a basic framework to greatly decrease the probability of TVS injury during neuronavigation procedures when supported by a good knowledge of the skull, brain anatomies and their relationships. PMID:26315333

  4. Knowledge modeling in image-guided neurosurgery: application in understanding intraoperative brain shift

    NASA Astrophysics Data System (ADS)

    Cohen-Adad, Julien; Paul, Perrine; Morandi, Xavier; Jannin, Pierre

    2006-03-01

    During an image-guided neurosurgery procedure, the neuronavigation system is subject to inaccuracy because of anatomical deformations which induce a gap between the preoperative images and their anatomical reality. Thus, the objective of many research teams is to succeed in quantifying these deformations in order to update preoperative images. Anatomical intraoperative deformations correspond to a complex spatio-temporal phenomenon. Our objective is to identify the parameters implicated in these deformations and to use these parameters as constrains for systems dedicated to updating preoperative images. In order to identify these parameters of deformation we followed the iterative methodology used for cognitive system conception: identification, conceptualization, formalization, implementation and validation. A state of the art about cortical deformations has been established in order to identify relevant parameters probably involved in the deformations. As a first step, 30 parameters have been identified and described following an ontological approach. They were formalized into a Unified Modeling Language (UML) class diagram. We implemented that model into a web-based application in order to fill a database. Two surgical cases have been studied at this moment. After having entered enough surgical cases for data mining purposes, we expect to identify the most relevant and influential parameters and to gain a better ability to understand the deformation phenomenon. This original approach is part of a global system aiming at quantifying and correcting anatomical deformations.

  5. Corticospinal tract mapping in children with ruptured arteriovenous malformations using functionally guided diffusion-tensor imaging.

    PubMed

    Ellis, Michael J; Rutka, James T; Kulkarni, Abhaya V; Dirks, Peter B; Widjaja, Elysa

    2012-05-01

    Arteriovenous malformations (AVMs) can lead to distortion or reorganization of functional brain anatomy, making localization of eloquent white matter tracts challenging. To improve the accuracy of corticospinal tract (CST) mapping, recent studies have examined the use of functional imaging techniques to help localize cortical motor activations and use these as seed points to reconstruct CSTs using diffusion-tensor imaging (DTI). The authors examined the role of pretreatment functionally guided DTI CST mapping in 3 children with ruptured AVMs. In 2 patients, magnetoencephalography motor activations were adjacent to the nidus and/or hemorrhagic cavity. However, in 1 child, functional MRI motor activations were detected in both hemispheres, suggestive of partial transfer of cortical motor function. In all children, quantitative analysis showed that fractional anisotropy values and fiber density indices were reduced in the CSTs of the hemisphere harboring the AVM compared with the unaffected side. In 2 children, CST caliber was slightly diminished, corresponding to no motor deficit in 1 patient and a temporary motor deficit in the other. In contrast, 1 child demonstrated marked reduction and displacement of the CSTs, correlating with severe motor deficit. Preoperative motor tractography data were loaded onto the intraoperative neuronavigation platform to guide complete resection of the AVM in 2 cases without permanent neurological deficits. These preliminary results confirm the feasibility of CST mapping in children with ruptured AVMs using functionally guided DTI tractography. Prospective studies are needed to assess the full value of this technique in the risk stratification, prognosis, and multimodality management of pediatric AVMs. PMID:22546028

  6. TMS reveals a direct influence of spinal projections from human SMAp on precise force production.

    PubMed

    Entakli, Jonathan; Bonnard, Mireille; Chen, Sophie; Berton, Eric; De Graaf, Jozina B

    2014-01-01

    The corticospinal (CS) system plays an important role in fine motor control, especially in precision grip tasks. Although the primary motor cortex (M1) is the main source of the CS projections, other projections have been found, especially from the supplementary motor area proper (SMAp). To study the characteristics of these CS projections from SMAp, we compared muscle responses of an intrinsic hand muscle (FDI) evoked by stimulation of human M1 and SMAp during an isometric static low-force control task. Subjects were instructed to maintain a small cursor on a target force curve by applying a pressure with their right precision grip on a force sensor. Neuronavigated transcranial magnetic stimulation was used to stimulate either left M1 or left SMAp with equal induced electric field values at the defined cortical targets. The results show that the SMAp stimulation evokes reproducible muscle responses with similar latencies and amplitudes as M1 stimulation, and with a clear and significant shorter silent period. These results suggest that (i) CS projections from human SMAp are as rapid and efficient as those from M1, (ii) CS projections from SMAp are directly involved in control of the excitability of spinal motoneurons and (iii) SMAp has a different intracortical inhibitory circuitry. We conclude that human SMAp and M1 both have direct influence on force production during fine manual motor tasks. PMID:24164635

  7. Initial experience of using high field strength intraoperative MRI for neurosurgical procedures.

    PubMed

    Raheja, Amol; Tandon, Vivek; Suri, Ashish; Sarat Chandra, P; Kale, Shashank S; Garg, Ajay; Pandey, Ravindra M; Kalaivani, Mani; Mahapatra, Ashok K; Sharma, Bhawani S

    2015-08-01

    We report our initial experience to optimize neurosurgical procedures using high field strength intraoperative magnetic resonance imaging (IOMRI) in 300 consecutive patients as high field strength IOMRI rapidly becomes the standard of care for neurosurgical procedures. Three sequential groups (groups A, B, C; n=100 each) were compared with respect to time management, complications and technical difficulties to assess improvement in these parameters with experience. We observed a reduction in the number of technical difficulties (p<0.001), time to induction (p<0.001) and total anesthesia time (p=0.007) in sequential groups. IOMRI was performed for neuronavigation guidance (n=252) and intraoperative validation of extent of resection (EOR; n=67). Performing IOMRI increased the EOR over and beyond the primary surgical attempt in 20.5% (29/141) and 18% (11/61) of patients undergoing glioma and pituitary surgery, respectively. Overall, EOR improved in 59.7% of patients undergoing IOMRI (40/67). Intraoperative tractography and real time navigation using re-uploaded IOMRI images (accounting for brain shift) helps in intraoperative planning to reduce complications. IOMRI is an asset to neurosurgeons, helping to augment the EOR, especially in glioma and pituitary surgery, with no significant increase in morbidity to the patient. PMID:26077939

  8. Computers and neurosurgery.

    PubMed

    Shaikhouni, Ammar; Elder, J Bradley

    2012-11-01

    At the turn of the twentieth century, the only computational device used in neurosurgical procedures was the brain of the surgeon. Today, most neurosurgical procedures rely at least in part on the use of a computer to help perform surgeries accurately and safely. The techniques that revolutionized neurosurgery were mostly developed after the 1950s. Just before that era, the transistor was invented in the late 1940s, and the integrated circuit was invented in the late 1950s. During this time, the first automated, programmable computational machines were introduced. The rapid progress in the field of neurosurgery not only occurred hand in hand with the development of modern computers, but one also can state that modern neurosurgery would not exist without computers. The focus of this article is the impact modern computers have had on the practice of neurosurgery. Neuroimaging, neuronavigation, and neuromodulation are examples of tools in the armamentarium of the modern neurosurgeon that owe each step in their evolution to progress made in computer technology. Advances in computer technology central to innovations in these fields are highlighted, with particular attention to neuroimaging. Developments over the last 10 years in areas of sensors and robotics that promise to transform the practice of neurosurgery further are discussed. Potential impacts of advances in computers related to neurosurgery in developing countries and underserved regions are also discussed. As this article illustrates, the computer, with its underlying and related technologies, is central to advances in neurosurgery over the last half century. PMID:22985531

  9. Semi-automated Volumetric and Morphological Assessment of Glioblastoma Resection with Fluorescence-Guided Surgery

    PubMed Central

    Cordova, J. Scott; Gurbani, Saumya S.; Holder, Chad A.; Olson, Jeffrey J.; Schreibmann, Eduard; Shi, Ran; Guo, Ying; Shu, Hui-Kuo G.; Shim, Hyunsuk; Hadjipanayis, Costas G.

    2016-01-01

    Purpose Glioblastoma (GBM) neurosurgical resection relies on contrast-enhanced MRI-based neuronavigation. However, it is well-known that infiltrating tumor extends beyond contrast enhancement. Fluorescence-guided surgery (FGS) using 5-aminolevulinic acid (5-ALA) was evaluated to improve extent of resection (EOR) of GBMs. Pre-operative morphological tumor metrics were also assessed. Procedures Thirty patients from a Phase II trial evaluating 5-ALA FGS in newly diagnosed GBM were assessed. Tumors were segmented pre-operatively to assess morphological features as well as post-operatively to evaluate EOR and residual tumor volume (RTV). Results Median EOR and RTV were 94.3% and 0.821 cm3, respectively. Pre-operative surface area to volume ratio and RTV were significantly associated with overall survival, even when controlling for the known survival confounders. Conclusions This study supports claims that 5-ALA FGS is helpful at decreasing tumor burden and prolonging survival in GBM. Moreover, morphological indices are shown to impact both resection and patient survival. PMID:26463215

  10. A systematic pipeline for the objective comparison of whole-brain spectroscopic MRI with histology in biopsy specimens from grade III glioma

    PubMed Central

    Cordova, J. Scott; Gurbani, Saumya S.; Olson, Jeffrey J.; Liang, Zhongxing; Cooper, Lee A. D.; Shu, Hui-Kuo G.; Schreibmann, Eduard; Neill, Stewart G.; Hadjipanayis, Constantinos G.; Holder, Chad A.; Shim, Hyunsuk

    2016-01-01

    The diagnosis, prognosis, and management of patients with gliomas are largely dictated by the pathological analysis of tissue biopsied from a selected region within the lesion. However, due to the heterogeneous and infiltrative nature of gliomas, identifying the optimal region for biopsy with conventional magnetic resonance imaging (MRI) can be quite difficult. This is especially true for low grade gliomas, which often are non-enhancing tumors. To improve the management of patients with these tumors, the field of neuro-oncology requires an imaging modality that can specifically identify a tumor’s most anaplastic/aggressive region(s) for biopsy targeting. The addition of metabolic mapping using spectroscopic MRI (sMRI) to supplement conventional MRI could improve biopsy targeting and, ultimately, diagnostic accuracy. Here, we describe a pipeline for the integration of state-of-the-art, high-resolution whole-brain 3D sMRI maps into a stereotactic neuronavigation system for guiding biopsies in gliomas with nonenhancing components. We also outline a machine-learning method for automated histology analysis that generates normalized, quantitative metrics describing tumor infiltration in immunohistochemically-stained tissue specimens. As a proof of concept, we describe the combination of these two techniques in a small cohort of grade III glioma patients. In this work, we aim to set forth a systematic pipeline to stimulate histopathology-image validation of advanced MRI techniques, such as sMRI. PMID:27489883

  11. Awake craniotomy using electromagnetic navigation technology without rigid pin fixation.

    PubMed

    Morsy, Ahmed A; Ng, Wai Hoe

    2015-11-01

    We report our institutional experience using an electromagnetic navigation system, without rigid head fixation, for awake craniotomy patients. The StealthStation® S7 AxiEM™ navigation system (Medtronic, Inc.) was used for this technique. Detailed preoperative clinical and neuropsychological evaluations, patient education and contrast-enhanced MRI (thickness 1.5mm) were performed for each patient. The AxiEM Mobile Emitter was typically placed in a holder, which was mounted to the operating room table, and a non-invasive patient tracker was used as the patient reference device. A monitored conscious sedation technique was used in all awake craniotomy patients, and the AxiEM Navigation Pointer was used for navigation during the procedure. This offers the same accuracy as optical navigation, but without head pin fixation or interference with intraoperative neurophysiological techniques and surgical instruments. The application of the electromagnetic neuronavigation technology without rigid head fixation during an awake craniotomy is accurate, and offers superior patient comfort. It is recommended as an effective adjunctive technique for the conduct of awake surgery. PMID:26249245

  12. Path to the Interpeduncular Fossa: Anatomical Comparison of Endoscopic-Assisted versus Standard Subtemporal Approach

    PubMed Central

    Lamki, Tariq; Salma, Asem; Baidya, Nishanta; Ammirati, Mario

    2012-01-01

    Objective The aim of this study was to assess the assumed advantage of endoscopic assistance to the standard subtemporal approach. The idea was to measure qualitatively and quantitatively visibility versus operability. Design We performed eight subtemporal dissections on four cadaver heads. Our dissections integrated an operating microscope, endoscope, and neuronavigation. Comparison was made between visibility and operability afforded by the microscope alone or by the microscope–endoscope combination. Visibility was recorded as complete or incomplete and was quantified for key structures using linear measurements taken by the navigation system. Operability was determined by whichever maneuvers could be safely and comfortably accomplished in the space afforded. Results From our survey, the structures whose visibility most benefitted from the addition of the endoscope include: contralateral third nerve, posterior perforated substance, mammillary bodies, and contralateral superior cerebellar artery. With regard to quantitative evaluation, we found increased visibility of both basilar artery and posterior cerebral artery. With regard to the operability, no objective advantage was afforded by the addition of the endoscope. Subjectively, the maneuvers were easier to perform while using the endoscope. Conclusion Using the endoscope as an assistance tool during conducting classical subtemporal approach can help in overcome a lot of the classical subtemporal approach limitations. PMID:23905002

  13. Presurgical navigated TMS motor cortex mapping improves outcome in glioblastoma surgery: a controlled observational study.

    PubMed

    Picht, Thomas; Frey, Dietmar; Thieme, Stefan; Kliesch, Stefan; Vajkoczy, Peter

    2016-02-01

    The authors report on an observational study designed to isolate the impact of navigated transcranial magnetic stimulation (nTMS) on surgical outcome in glioblastoma treatment. We undertook a controlled observational study to identify the additive impact of presurgical nTMS in patients scheduled for surgical treatment of glioblastoma in or near motor eloquent locations. The trial data is derived from a large university hospital with a differential availability of its nTMS mapping service at its two campuses, both equally served by a single neurosurgical department. When available, the nTMS cortical mapping data and nTMS-based fiber tractography are used for surgical planning and patient counseling as well as intraoperative identification of the primary motor cortex and guidance in subcortical motor mapping. The addition of preoperative nTMS mapping data to a clinical routine already incorporating preoperative fiber tractography and intraoperative neuronavigation and electrophysiology was shown to improve surgical outcomes by increasing the extent of resection, without compromising patient safety or long-term functional outcomes in comparison to the concurrent non-TMS control group. This study is the first to prove that the improved surgical outcomes observed in previous studies after the implementation of nTMS to presurgical work-up are not caused by any overall improvement in patient care or a paradigm shift toward more aggressive resection but by the additional functional data provided by nTMS. PMID:26566653

  14. Noninvasive stimulation of the temporoparietal junction: A systematic review.

    PubMed

    Donaldson, Peter H; Rinehart, Nicole J; Enticott, Peter G

    2015-08-01

    Imaging and lesion studies have suggested numerous roles for the temporoparietal junction (TPJ), for example in attention and neglect, social cognition, and self/other processing. These studies cannot establish causal relationships, and the importance and relevance of (and interrelationships between) proposed roles remain controversial. This review examined studies that use noninvasive transcranial stimulation (NTS) to explore TPJ function. Of the 459 studies identified, 40 met selection criteria. The strengths and weaknesses of NTS-relevant parameters used are discussed, and methodological improvements suggested. These include the need for careful selection of stimulation sites and experimental tasks, and use of neuronavigation and concurrent functional activity measures. Without such improvements, overlapping and discrete functions of the TPJ will be difficult to disentangle. Nevertheless, the contributions of these studies to theoretical models of TPJ function are discussed, and the clinical relevance of TPJ stimulation explored. Some evidence exists for TPJ stimulation in the treatment of auditory hallucinations, tinnitus, and depersonalisation disorder. Further examination of the TPJ in conditions such as autism spectrum disorder is also warranted. PMID:26073069

  15. Navigation-supported diagnosis of the substantia nigra by matching midbrain sonography and MRI

    NASA Astrophysics Data System (ADS)

    Salah, Zein; Weise, David; Preim, Bernhard; Classen, Joseph; Rose, Georg

    2012-03-01

    Transcranial sonography (TCS) is a well-established neuroimaging technique that allows for visualizing several brainstem structures, including the substantia nigra, and helps for the diagnosis and differential diagnosis of various movement disorders, especially in Parkinsonian syndromes. However, proximate brainstem anatomy can hardly be recognized due to the limited image quality of B-scans. In this paper, a visualization system for the diagnosis of the substantia nigra is presented, which utilizes neuronavigated TCS to reconstruct tomographical slices from registered MRI datasets and visualizes them simultaneously with corresponding TCS planes in realtime. To generate MRI tomographical slices, the tracking data of the calibrated ultrasound probe are passed to an optimized slicing algorithm, which computes cross sections at arbitrary positions and orientations from the registered MRI dataset. The extracted MRI cross sections are finally fused with the region of interest from the ultrasound image. The system allows for the computation and visualization of slices at a near real-time rate. Primary tests of the system show an added value to the pure sonographic imaging. The system also allows for reconstructing volumetric (3D) ultrasonic data of the region of interest, and thus contributes to enhancing the diagnostic yield of midbrain sonography.

  16. A Pipeline for 3D Multimodality Image Integration and Computer-assisted Planning in Epilepsy Surgery

    PubMed Central

    Nowell, Mark; Rodionov, Roman; Zombori, Gergely; Sparks, Rachel; Rizzi, Michele; Ourselin, Sebastien; Miserocchi, Anna; McEvoy, Andrew; Duncan, John

    2016-01-01

    Epilepsy surgery is challenging and the use of 3D multimodality image integration (3DMMI) to aid presurgical planning is well-established. Multimodality image integration can be technically demanding, and is underutilised in clinical practice. We have developed a single software platform for image integration, 3D visualization and surgical planning. Here, our pipeline is described in step-by-step fashion, starting with image acquisition, proceeding through image co-registration, manual segmentation, brain and vessel extraction, 3D visualization and manual planning of stereoEEG (SEEG) implantations. With dissemination of the software this pipeline can be reproduced in other centres, allowing other groups to benefit from 3DMMI. We also describe the use of an automated, multi-trajectory planner to generate stereoEEG implantation plans. Preliminary studies suggest this is a rapid, safe and efficacious adjunct for planning SEEG implantations. Finally, a simple solution for the export of plans and models to commercial neuronavigation systems for implementation of plans in the operating theater is described. This software is a valuable tool that can support clinical decision making throughout the epilepsy surgery pathway. PMID:27286266

  17. Ventrolateral prefrontal cortex repetitive transcranial magnetic stimulation in the treatment of depersonalization disorder: A consecutive case series.

    PubMed

    Jay, Emma-Louise; Nestler, Steffen; Sierra, Mauricio; McClelland, Jessica; Kekic, Maria; David, Anthony S

    2016-06-30

    Case reports and an open trial have reported promising responses to repetitive transcranial magnetic stimulation (rTMS) to prefrontal and temporo-parietal sites in patients with depersonalization disorder (DPD). We recently showed that a single session of rTMS to the ventrolateral prefrontal cortex (VLPFC) was associated with a reduction in symptoms and increase in physiological arousal. Seven patients with medication-resistant DSM-IV DPD received up to 20 sessions of right-sided rTMS to the VLPFC for 10 weeks. Stimulation was guided using neuronavigation software based on participants' individual structural MRIs, and delivered at 110% of resting motor threshold. A session consisted of 1Hz repetitive TMS for 15min. The primary outcome measure was reduction in depersonalization symptoms on the Cambridge Depersonalization Scale (CDS). Secondary outcomes included scores on the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). 20 sessions of rTMS treatment to right VLPFC significantly reduced scores on the CDS by on average 44% (range 2-83.5%). Two patients could be classified as "full responders", four as "partial" and one a non-responder. Response usually occurred within the first 6 sessions. There were no significant adverse events. A randomized controlled clinical trial of VLPFC rTMS for DPD is warranted. PMID:27104926

  18. Transcranial magnetic stimulation in schizophrenia: the contribution of neuroimaging.

    PubMed

    Du, Zhong-de; Wang, R; Prakash, Ravi; Chaudhury, S; Dayananda, G

    2012-01-01

    At the most basic level, the Transcranial Magnetic Stimulation(TMS) is a neuro-scientific tool that exerts its action by influencing the neo-cortical functions. However, in-spite of so many well-evidenced roles of TMS in neuropsychiatric conditions, its exact mechanism of action remains to be known. More intriguing are its therapeutic effects in Schizophrenia at the Cerebral-level. In this review, we adopt a neuro-imaging approach for this exploration. We review the present literature for the studies in Schizophrenia which have used a combination of rTMS with 1) Electroenchephalogram (EEG) 2)The functional Magnetic Resonance Imaging (fMRI) and the 3) Positron Emission Tomography (PET)/ Single-Photon Emission Computed Tomography. The TMS-EEG combination provides direct effects of TMS on the electro- magnetic field (EMF) of brain. The TMS-fMRI/PET/SPECT combinations are very effective in exploring the functional connectivity in brains of Schizophrenia patients as well as in performing rTMS guided neuro-navigation. Our review suggests that TMS combined with other neuroimaging modalities are needed for a better clarification of its neural actions. PMID:23409741

  19. Facilitatory effect of paired-pulse stimulation by transcranial magnetic stimulation with biphasic wave-form.

    PubMed

    Julkunen, Petro; Järnefelt, Gustaf; Savolainen, Petri; Laine, Jarmo; Karhu, Jari

    2016-08-01

    Transcranial magnetic stimulation (TMS) is used to probe corticospinal excitability by stimulating the motor cortex. Our aim was to enhance the effects of biphasic TMS by coupling a suprathreshold test pulse and a following subthreshold priming pulse to induce short-interval intracortical facilitation (SICF), which is conventionally produced with monophasic TMS. Biphasic TMS could potentially induce the SICF effect with better energy-efficiency and with lower stimulus intensities. This would make the biphasic paired-pulses better applicable in patients with reduced cortical excitability. A prototype stimulator was built to produce biphasic paired-pulses. Resting motor thresholds (rMTs) from the right and left hand abductor pollicis brevis muscles, and the right tibialis anterior muscle of eight healthy volunteers were determined using single-pulse paradigm with neuronavigated TMS. The rMTs and MEPs were measured using single-pulses and three paired-pulse setups (interstimulus interval, ISI of 3, 7 or 15ms). The rMTs were lower and MEPs were higher with biphasic paired-pulses compared to single-pulses. The SICF effect was greatest at 3ms ISI. This suggests that the application of biphasic paired-pulses to enhance stimulation effects is possible. PMID:27215172

  20. The right temporoparietal junction in attention and social interaction: A transcranial magnetic stimulation study.

    PubMed

    Krall, Sarah C; Volz, Lukas J; Oberwelland, Eileen; Grefkes, Christian; Fink, Gereon R; Konrad, Kerstin

    2016-02-01

    The right temporoparietal junction (rTPJ) has been associated with the ability to reorient attention to unexpected stimuli and the capacity to understand others' mental states (theory of mind [ToM]/false belief). Using activation likelihood estimation meta-analysis we previously unraveled that the anterior rTPJ is involved in both, reorienting of attention and ToM, possibly indicating a more general role in attention shifting. Here, we used neuronavigated transcranial magnetic stimulation to directly probe the role of the rTPJ across attentional reorienting and false belief. Task performance in a visual cueing paradigm and false belief cartoon task was investigated after application of continuous theta burst stimulation (cTBS) over anterior rTPJ (versus vertex, for control). We found that attentional reorienting was significantly impaired after rTPJ cTBS compared with control. For the false belief task, error rates in trials demanding a shift in mental state significantly increased. Of note, a significant positive correlation indicated a close relation between the stimulation effect on attentional reorienting and false belief trials. Our findings extend previous neuroimaging evidence by indicating an essential overarching role of the anterior rTPJ for both cognitive functions, reorienting of attention and ToM. Hum Brain Mapp 37:796-807, 2016. © 2015 Wiley Periodicals, Inc. PMID:26610283

  1. Effect of repetitive transcranial magnetic stimulation on mood in healthy subjects

    PubMed Central

    Moulier, Virginie; Gaudeau-Bosma, Christian; Isaac, Clémence; Allard, Anne-Camille; Bouaziz, Noomane; Sidhoumi, Djedia; Braha-Zeitoun, Sonia; Benadhira, René; Thomas, Fanny; Januel, Dominique

    2016-01-01

    Background High frequency repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) has shown significant efficiency in the treatment of resistant depression. However in healthy subjects, the effects of rTMS remain unclear. Objective Our aim was to determine the impact of 10 sessions of rTMS applied to the DLPFC on mood and emotion recognition in healthy subjects. Design In a randomised double-blind study, 20 subjects received 10 daily sessions of active (10 Hz frequency) or sham rTMS. The TMS coil was positioned on the left DLPFC through neuronavigation. Several dimensions of mood and emotion processing were assessed at baseline and after rTMS with clinical scales, visual analogue scales (VASs), and the Ekman 60 faces test. Results The 10 rTMS sessions targeting the DLPFC were well tolerated. No significant difference was found between the active group and the control group for clinical scales and the Ekman 60 faces test. Compared to the control group, the active rTMS group presented a significant improvement in their adaptation to daily life, which was assessed through VAS. Conclusion This study did not show any deleterious effect on mood and emotion recognition of 10 sessions of rTMS applied on the DLPFC in healthy subjects. This study also suggested a positive effect of rTMS on quality of life. PMID:26993786

  2. Evaluation of Language Function under Awake Craniotomy

    PubMed Central

    KANNO, Aya; MIKUNI, Nobuhiro

    2015-01-01

    Awake craniotomy is the only established way to assess patients’ language functions intraoperatively and to contribute to their preservation, if necessary. Recent guidelines have enabled the approach to be used widely, effectively, and safely. Non-invasive brain functional imaging techniques, including functional magnetic resonance imaging and diffusion tensor imaging, have been used preoperatively to identify brain functional regions corresponding to language, and their accuracy has increased year by year. In addition, the use of neuronavigation that incorporates this preoperative information has made it possible to identify the positional relationships between the lesion and functional regions involved in language, conduct functional brain mapping in the awake state with electrical stimulation, and intraoperatively assess nerve function in real time when resecting the lesion. This article outlines the history of awake craniotomy, the current state of pre- and intraoperative evaluation of language function, and the clinical usefulness of such functional evaluation. When evaluating patients’ language functions during awake craniotomy, given the various intraoperative stresses involved, it is necessary to carefully select the tasks to be undertaken, quickly perform all examinations, and promptly evaluate the results. As language functions involve both input and output, they are strongly affected by patients’ preoperative cognitive function, degree of intraoperative wakefulness and fatigue, the ability to produce verbal articulations and utterances, as well as perform synergic movement. Therefore, it is essential to appropriately assess the reproducibility of language function evaluation using awake craniotomy techniques. PMID:25925758

  3. Motor cortex stimulation for neuropathic pain.

    PubMed

    Lazorthes, Y; Sol, J C; Fowo, S; Roux, F E; Verdié, J C

    2007-01-01

    Since the initial publication of Tsubokawa in 1991, epidural motor cortex stimulation (MCS) is increasingly reported as an effective surgical option for the treatment of refractory neuropathic pain although its mechanism of action remains poorly understood. The authors review the extensive literature published over the last 15 years on central and neuropathic pain. Optimal patient selection remains difficult and the value of pharmacological tests or transcranial magnetic stimulation in predicting the efficacy of MCS has not been established. Pre-operative functional magnetic resonance imaging (fMRI), 3-dimensional volume MRI, neuronavigation and intra-operative neurophysiological monitoring have contributed to improvements in the technique for identifying the precise location of the targeted motor cortical area and the correct placement of the electrode array. MCS should be considered as the treatment of choice in post-stroke pain, thalamic pain or facial anesthesia dolorosa. In brachial plexus avulsion pain, it is preferable to propose initially dorsal root entry zone (DREZ)-tomy; MCS may be offered after DREZotomy has failed to control the pain. In our experience, the results of MCS on phantom limb pain are promising. In general, the efficacy of MCS depends on: a) the accurate placement of the stimulation electrode over the appropriate area of the motor cortex, and b) on sophisticated programming of the stimulation parameters. A better understanding of the MCS mechanism of action will probably make it possible to adjust better the stimulation parameters. The conclusions of multicentered randomised studies, now in progress, will be very useful and are likely to promote further research and clinical applications in this field. PMID:17691287

  4. Single slice US-MRI registration for neurosurgical MRI-guided US

    NASA Astrophysics Data System (ADS)

    Pardasani, Utsav; Baxter, John S. H.; Peters, Terry M.; Khan, Ali R.

    2016-03-01

    Image-based ultrasound to magnetic resonance image (US-MRI) registration can be an invaluable tool in image-guided neuronavigation systems. State-of-the-art commercial and research systems utilize image-based registration to assist in functions such as brain-shift correction, image fusion, and probe calibration. Since traditional US-MRI registration techniques use reconstructed US volumes or a series of tracked US slices, the functionality of this approach can be compromised by the limitations of optical or magnetic tracking systems in the neurosurgical operating room. These drawbacks include ergonomic issues, line-of-sight/magnetic interference, and maintenance of the sterile field. For those seeking a US vendor-agnostic system, these issues are compounded with the challenge of instrumenting the probe without permanent modification and calibrating the probe face to the tracking tool. To address these challenges, this paper explores the feasibility of a real-time US-MRI volume registration in a small virtual craniotomy site using a single slice. We employ the Linear Correlation of Linear Combination (LC2) similarity metric in its patch-based form on data from MNI's Brain Images for Tumour Evaluation (BITE) dataset as a PyCUDA enabled Python module in Slicer. By retaining the original orientation information, we are able to improve on the poses using this approach. To further assist the challenge of US-MRI registration, we also present the BOXLC2 metric which demonstrates a speed improvement to LC2, while retaining a similar accuracy in this context.

  5. Electrophysiological and Anatomical Correlates of Spinal Cord Optical Coherence Tomography

    PubMed Central

    Valente, Maurizio; Krstajic, Nikola; Biella, Gabriele E. M.

    2016-01-01

    Despite the continuous improvement in medical imaging technology, visualizing the spinal cord poses severe problems due to structural or incidental causes, such as small access space and motion artifacts. In addition, positional guidance on the spinal cord is not commonly available during surgery, with the exception of neuronavigation techniques based on static pre-surgical data and of radiation-based methods, such as fluoroscopy. A fast, bedside, intraoperative real-time imaging, particularly necessary during the positioning of endoscopic probes or tools, is an unsolved issue. The objective of our work, performed on experimental rats, is to demonstrate potential intraoperative spinal cord imaging and probe guidance by optical coherence tomography (OCT). Concurrently, we aimed to demonstrate that the electromagnetic OCT irradiation exerted no particular effect at the neuronal and synaptic levels. OCT is a user-friendly, low-cost and endoscopy-compatible photonics-based imaging technique. In particular, by using a Fourier-domain OCT imager, operating at 850 nm wavelength and scanning transversally with respect to the spinal cord, we have been able to: 1) accurately image tissue structures in an animal model (muscle, spine bone, cerebro-spinal fluid, dura mater and spinal cord), and 2) identify the position of a recording microelectrode approaching and inserting into the cord tissue 3) check that the infrared radiation has no actual effect on the electrophysiological activity of spinal neurons. The technique, potentially extendable to full three-dimensional image reconstruction, shows prospective further application not only in endoscopic intraoperative analyses and for probe insertion guidance, but also in emergency and adverse situations (e.g. after trauma) for damage recognition, diagnosis and fast image-guided intervention. PMID:27050096

  6. Image guided surgery in the management of craniocerebral gunshot injuries

    PubMed Central

    Elserry, Tarek; Anwer, Hesham; Esene, Ignatius Ngene

    2013-01-01

    Background: A craniocerebral trauma caused by firearms is a complex injury with high morbidity and mortality. One of the most intriguing and controversial part in their management in salvageable patients is the decision to remove the bullet/pellet. A bullet is foreign to the brain and, in principle, should be removed. Surgical options for bullet extraction span from conventional craniotomy, through C-arm-guided surgery to minimally invasive frame or frameless stereotaxy. But what is the best surgical option? Methods: We prospectively followed up a cohort of 28 patients with cranio-cerebral gunshot injury (CCHSI) managed from January to December 2012 in our department of neurosurgery. The missiles were extracted via stereotaxy (frame or frameless), C-arm-guided, or free-hand-based surgery. Cases managed conservatively were excluded. The Glasgow Outcome Score was used to assess the functional outcome on discharge. Results: Five of the eight “stereotactic cases” had an excellent outcome after missile extraction while the initially planned stereotaxy missed locating the missile in three cases and were thus subjected to free hand craniotomy. Excellent outcome was obtained in five of the nine “neuronavigation cases, five of the eight cases for free hand surgery based on the bony landmarks, and five of the six C-arm-based surgery. Conclusion: Conventional craniotomy isn’t indicated in the extraction of isolated, retained, intracranial firearm missiles in civilian injury but could be useful when the missile is incorporated within a surgical lesion. Stereotactic surgery could be useful for bullet extraction, though with limited precision in identifying small pellets because of their small sizes, thus exposing patients to same risk of brain insult when retrieving a missile by conventional surgery. Because of its availability, C-arm-guided surgery continues to be of much benefit, especially in emergency situations. We recommend an extensive long-term study of these

  7. An integrated model-based neurosurgical guidance system

    NASA Astrophysics Data System (ADS)

    Ji, Songbai; Fan, Xiaoyao; Fontaine, Kathryn; Hartov, Alex; Roberts, David; Paulsen, Keith

    2010-02-01

    Maximal tumor resection without damaging healthy tissue in open cranial surgeries is critical to the prognosis for patients with brain cancers. Preoperative images (e.g., preoperative magnetic resonance images (pMR)) are typically used for surgical planning as well as for intraoperative image-guidance. However, brain shift even at the start of surgery significantly compromises the accuracy of neuronavigation, if the deformation is not compensated for. Compensating for brain shift during surgical operation is, therefore, critical for improving the accuracy of image-guidance and ultimately, the accuracy of surgery. To this end, we have developed an integrated neurosurgical guidance system that incorporates intraoperative three-dimensional (3D) tracking, acquisition of volumetric true 3D ultrasound (iUS), stereovision (iSV) and computational modeling to efficiently generate model-updated MR image volumes for neurosurgical guidance. The system is implemented with real-time Labview to provide high efficiency in data acquisition as well as with Matlab to offer computational convenience in data processing and development of graphical user interfaces related to computational modeling. In a typical patient case, the patient in the operating room (OR) is first registered to pMR image volume. Sparse displacement data extracted from coregistered intraoperative US and/or stereovision images are employed to guide a computational model that is based on consolidation theory. Computed whole-brain deformation is then used to generate a model-updated MR image volume for subsequent surgical guidance. In this paper, we present the key modular components of our integrated, model-based neurosurgical guidance system.

  8. Transcranial direct current stimulation (tDCS) of left parietal cortex facilitates gesture processing in healthy subjects.

    PubMed

    Weiss, Peter H; Achilles, Elisabeth I S; Moos, Katharina; Hesse, Maike D; Sparing, Roland; Fink, Gereon R

    2013-12-01

    Gesture processing deficits constitute a key symptom of apraxia, a disorder of motor cognition frequently observed after left-hemispheric stroke. The clinical relevance of apraxia stands in stark contrast to the paucity of therapeutic options available. Transcranial direct current stimulation (tDCS) is a promising tool for modulating disturbed network function after stroke. Here, we investigate the effect of parietal tDCS on gesture processing in healthy human subjects. Neuropsychological and imaging studies suggest that the imitation and matching of hand gestures involve the left inferior parietal lobe (IPL). Using neuronavigation based on cytoarchitectonically defined anatomical probability maps, tDCS was applied over left IPL-areas PF, PFm, or PG in healthy participants (n = 26). Before and after tDCS, subjects performed a gesture matching task and a person discrimination task for control. Changes in error rates and reaction times were analyzed for the effects of anodal and cathodal tDCS (compared with sham tDCS). Matching of hand gestures was specifically facilitated by anodal tDCS applied over the cytoarchitectonically defined IPL-area PFm, whereas tDCS over IPL-areas PF and PG did not elucidate significant effects. Taking into account tDCS electrode size and the central position of area PFm within IPL, it can be assumed that the observed effect is rather the result of a combined stimulation of the supramarginal and angular gyrus than an isolated PFm stimulation. Our data confirm the pivotal role of the left IPL in gesture processing. Furthermore, anatomically guided tDCS of the left IPL may constitute a promising approach to neurorehabilitation of apraxic patients with gesture processing deficits. PMID:24305816

  9. Versatile utilization of real-time intraoperative contrast-enhanced ultrasound in cranial neurosurgery: technical note and retrospective case series.

    PubMed

    Lekht, Ilya; Brauner, Noah; Bakhsheshian, Joshua; Chang, Ki-Eun; Gulati, Mittul; Shiroishi, Mark S; Grant, Edward G; Christian, Eisha; Zada, Gabriel

    2016-03-01

    OBJECTIVE Intraoperative contrast-enhanced ultrasound (iCEUS) offers dynamic imaging and provides functional data in real time. However, no standardized protocols or validated quantitative data exist to guide its routine use in neurosurgery. The authors aimed to provide further clinical data on the versatile application of iCEUS through a technical note and illustrative case series. METHODS Five patients undergoing craniotomies for suspected tumors were included. iCEUS was performed using a contrast agent composed of lipid shell microspheres enclosing perflutren (octafluoropropane) gas. Perfusion data were acquired through a time-intensity curve analysis protocol obtained using iCEUS prior to biopsy and/or resection of all lesions. RESULTS Three primary tumors (gemistocytic astrocytoma, glioblastoma multiforme, and meningioma), 1 metastatic lesion (melanoma), and 1 tumefactive demyelinating lesion (multiple sclerosis) were assessed using real-time iCEUS. No intraoperative complications occurred following multiple administrations of contrast agent in all cases. In all neoplastic cases, iCEUS replicated enhancement patterns observed on preoperative Gd-enhanced MRI, facilitated safe tumor debulking by differentiating neoplastic tissue from normal brain parenchyma, and helped identify arterial feeders and draining veins in and around the surgical cavity. Intraoperative CEUS was also useful in guiding a successful intraoperative needle biopsy of a cerebellar tumefactive demyelinating lesion obtained during real-time perfusion analysis. CONCLUSIONS Intraoperative CEUS has potential for safe, real-time, dynamic contrast-based imaging for routine use in neurooncological surgery and image-guided biopsy. Intraoperative CEUS eliminates the effect of anatomical distortions associated with standard neuronavigation and provides quantitative perfusion data in real time, which may hold major implications for intraoperative diagnosis, tissue differentiation, and quantification of

  10. Mass Spectrometry Imaging as a Tool for Surgical Decision-Making

    PubMed Central

    Calligaris, David; Norton, Isaiah; Feldman, Daniel R.; Ide, Jennifer L.; Dunn, Ian F.; Eberlin, Livia S.; Cooks, R. Graham; Jolesz, Ferenc A.; Golby, Alexandra J.; Santagata, Sandro; Agar, Nathalie Y.

    2014-01-01

    Despite significant advances in image-guided therapy, surgeons are still too often left with uncertainty when deciding to remove tissue. This binary decision between removing and leaving tissue during surgery implies that the surgeon should be able to distinguish tumor from healthy tissue. In neurosurgery, current image-guidance approaches such as magnetic resonance imaging (MRI) combined with neuro-navigation offer a map as to where the tumor should be, but the only definitive method to characterize the tissue at stake is histopathology. While extremely valuable information is derived from this gold standard approach, it is limited to very few samples during surgery and is not practically used for the delineation of tumor margins. The development and implementation of faster, comprehensive and complementary approaches for tissue characterization are required to support surgical decision-making – an incremental and iterative process with tumor removed in multiple and often minute biopsies. The development of atmospheric pressure ionization sources makes it possible to analyze tissue specimens with little to no sample preparation. Here, we highlight the value of desorption electrospray ionization (DESI) as one of many available approaches for the analysis of surgical tissue. Twelve surgical samples resected from a patient during surgery were analyzed and diagnosed as glioblastoma (GBM) tumor or necrotic tissue by standard histopathology, and mass spectrometry results were further correlated to histopathology for critical validation of the approach. The use of a robust statistical approach reiterated results from the qualitative detection of potential biomarkers of these tissue types. The correlation of the MS and histopathology results to magnetic resonance images brings significant insight into tumor presentation that could not only serve to guide tumor resection, but that is worthy of more detailed studies on our understanding of tumor presentation on MRI. PMID

  11. Modulatory Effects of Theta Burst Stimulation on Cerebellar Nonsomatic Functions

    PubMed Central

    Demirtas-Tatlidede, Asli; Freitas, Catarina; Pascual-Leone, Alvaro; Schmahmann, Jeremy D.

    2011-01-01

    Clinical and functional imaging studies suggest that the cerebellar vermis is involved in the regulation of a range of nonsomatic functions including cardiovascular control, thirst, feeding behavior, and primal emotions. Cerebello-hypothalamic circuits have been postulated to be a potential neuroanatomical substrate underlying this modulation. We tested this putative relationship between the cerebellar vermis and nonsomatic functions by stimulating the cerebellum noninvasively via neuronavigated transcranial magnetic stimulation. In this randomized, counter-balanced, within-subject study, intermittent theta burst stimulation (TBS) was applied on three different days to the vermis and the right and left cerebellar hemispheres of 12 right-handed normal subjects with the aim of modulating activity in the targeted cerebellar structure. TBS-associated changes were investigated via cardiovascular monitoring, a series of emotionally arousing picture stimuli, subjective analog scales for primal emotions, and the Profile of Mood States test. All 36 sessions of cerebellar stimulation were tolerated well without serious adverse events. Cardiovascular monitoring pointed to a mild but significant decrease in heart rate subsequent to vermal stimulation; no changes were detected in systolic or diastolic blood pressure measurements. Subjective ratings detected a significant increase in Thirst and a trend toward increased Appetite following vermal stimulation. These observations are consistent with existing neurophysiological and neuroimaging data indicating a role for the cerebellum in the regulation of visceral responses. In conjunction with the modulatory function of the cerebellum, our results suggest a role for the vermis in somatovisceral integration likely through cerebello-hypothalamic pathways. Further research is warranted to elucidate the potential mechanisms underlying the cerebellar modulation of nonsomatic functions. PMID:21132574

  12. Retractor-induced brain shift compensation in image-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Fan, Xiaoyao; Ji, Songbai; Hartov, Alex; Roberts, David; Paulsen, Keith

    2013-03-01

    In image-guided neurosurgery, intraoperative brain shift significantly degrades the accuracy of neuronavigation that is solely based on preoperative magnetic resonance images (pMR). To compensate for brain deformation and to maintain the accuracy in image guidance achieved at the start of surgery, biomechanical models have been developed to simulate brain deformation and to produce model-updated MR images (uMR) to compensate for brain shift. To-date, most studies have focused on shift compensation at early stages of surgery (i.e., updated images are only produced after craniotomy and durotomy). Simulating surgical events at later stages such as retraction and tissue resection are, perhaps, clinically more relevant because of the typically much larger magnitudes of brain deformation. However, these surgical events are substantially more complex in nature, thereby posing significant challenges in model-based brain shift compensation strategies. In this study, we present results from an initial investigation to simulate retractor-induced brain deformation through a biomechanical finite element (FE) model where whole-brain deformation assimilated from intraoperative data was used produce uMR for improved accuracy in image guidance. Specifically, intensity-encoded 3D surface profiles at the exposed cortical area were reconstructed from intraoperative stereovision (iSV) images before and after tissue retraction. Retractor-induced surface displacements were then derived by coregistering the surfaces and served as sparse displacement data to drive the FE model. With one patient case, we show that our technique is able to produce uMR that agrees well with the reconstructed iSV surface after retraction. The computational cost to simulate retractor-induced brain deformation was approximately 10 min. In addition, our approach introduces minimal interruption to the surgical workflow, suggesting the potential for its clinical application.

  13. Optimizing nonrigid registration performance between volumetric true 3D ultrasound images in image-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Ji, Songbai; Fan, Xiaoyao; Roberts, David W.; Hartov, Alex; Paulsen, Keith D.

    2011-03-01

    Compensating for brain shift as surgery progresses is important to ensure sufficient accuracy in patient-to-image registration in the operating room (OR) for reliable neuronavigation. Ultrasound has emerged as an important and practical imaging technique for brain shift compensation either by itself or through computational modeling that estimates whole-brain deformation. Using volumetric true 3D ultrasound (3DUS), it is possible to nonrigidly (e.g., based on B-splines) register two temporally different 3DUS images directly to generate feature displacement maps for data assimilation in the biomechanical model. Because of a large amount of data and number of degrees-of-freedom (DOFs) involved, however, a significant computational cost may be required that can adversely influence the clinical feasibility of the technique for efficiently generating model-updated MR (uMR) in the OR. This paper parametrically investigates three B-splines registration parameters and their influence on the computational cost and registration accuracy: number of grid nodes along each direction, floating image volume down-sampling rate, and number of iterations. A simulated rigid body displacement field was employed as a ground-truth against which the accuracy of displacements generated from the B-splines nonrigid registration was compared. A set of optimal parameters was then determined empirically that result in a registration computational cost of less than 1 min and a sub-millimetric accuracy in displacement measurement. These resulting parameters were further applied to a clinical surgery case to demonstrate their practical use. Our results indicate that the optimal set of parameters result in sufficient accuracy and computational efficiency in model computation, which is important for future application of the overall biomechanical modeling to generate uMR for image-guidance in the OR.

  14. Simulation of brain tumor resection in image-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Fan, Xiaoyao; Ji, Songbai; Fontaine, Kathryn; Hartov, Alex; Roberts, David; Paulsen, Keith

    2011-03-01

    Preoperative magnetic resonance images are typically used for neuronavigation in image-guided neurosurgery. However, intraoperative brain deformation (e.g., as a result of gravitation, loss of cerebrospinal fluid, retraction, resection, etc.) significantly degrades the accuracy in image guidance, and must be compensated for in order to maintain sufficient accuracy for navigation. Biomechanical finite element models are effective techniques that assimilate intraoperative data and compute whole-brain deformation from which to generate model-updated MR images (uMR) to improve accuracy in intraoperative guidance. To date, most studies have focused on early surgical stages (i.e., after craniotomy and durotomy), whereas simulation of more complex events at later surgical stages has remained to be a challenge using biomechanical models. We have developed a method to simulate partial or complete tumor resection that incorporates intraoperative volumetric ultrasound (US) and stereovision (SV), and the resulting whole-brain deformation was used to generate uMR. The 3D ultrasound and stereovision systems are complimentary to each other because they capture features deeper in the brain beneath the craniotomy and at the exposed cortical surface, respectively. In this paper, we illustrate the application of the proposed method to simulate brain tumor resection at three temporally distinct surgical stages throughout a clinical surgery case using sparse displacement data obtained from both the US and SV systems. We demonstrate that our technique is feasible to produce uMR that agrees well with intraoperative US and SV images after dural opening, after partial tumor resection, and after complete tumor resection. Currently, the computational cost to simulate tumor resection can be up to 30 min because of the need for re-meshing and the trial-and-error approach to refine the amount of tissue resection. However, this approach introduces minimal interruption to the surgical workflow

  15. Screw Placement Accuracy and Outcomes Following O-Arm-Navigated Atlantoaxial Fusion: A Feasibility Study.

    PubMed

    Smith, Jacob D; Jack, Megan M; Harn, Nicholas R; Bertsch, Judson R; Arnold, Paul M

    2016-06-01

    Study Design Case series of seven patients. Objective C2 stabilization can be challenging due to the complex anatomy of the upper cervical vertebrae. We describe seven cases of C1-C2 fusion using intraoperative navigation to aid in the screw placement at the atlantoaxial (C1-C2) junction. Methods Between 2011 and 2014, seven patients underwent posterior atlantoaxial fusion using intraoperative frameless stereotactic O-arm Surgical Imaging and StealthStation Surgical Navigation System (Medtronic, Inc., Minneapolis, Minnesota, United States). Outcome measures included screw accuracy, neurologic status, radiation dosing, and surgical complications. Results Four patients had fusion at C1-C2 only, and in the remaining three, fixation extended down to C3 due to anatomical considerations for screw placement recognized on intraoperative imaging. Out of 30 screws placed, all demonstrated minimal divergence from desired placement in either C1 lateral mass, C2 pedicle, or C3 lateral mass. No neurovascular compromise was seen following the use of intraoperative guided screw placement. The average radiation dosing due to intraoperative imaging was 39.0 mGy. All patients were followed for a minimum of 12 months. All patients went on to solid fusion. Conclusion C1-C2 fusion using computed tomography-guided navigation is a safe and effective way to treat atlantoaxial instability. Intraoperative neuronavigation allows for high accuracy of screw placement, limits complications by sparing injury to the critical structures in the upper cervical spine, and can help surgeons make intraoperative decisions regarding complex pathology. PMID:27190736

  16. Intermittent Theta Burst Stimulation Increases Reward Responsiveness in Individuals with Higher Hedonic Capacity

    PubMed Central

    Duprat, Romain; De Raedt, Rudi; Wu, Guo-Rong; Baeken, Chris

    2016-01-01

    Background: Repetitive transcranial magnetic stimulation over the left dorsolateral prefrontal cortex (DLPFC) has been documented to influence striatal and orbitofrontal dopaminergic activity implicated in reward processing. However, the exact neuropsychological mechanisms of how DLPFC stimulation may affect the reward system and how trait hedonic capacity may interact with the effects remains to be elucidated. Objective: In this sham-controlled study in healthy individuals, we investigated the effects of a single session of neuronavigated intermittent theta burst stimulation (iTBS) on reward responsiveness, as well as the influence of trait hedonic capacity. Methods: We used a randomized crossover single session iTBS design with an interval of 1 week. We assessed reward responsiveness using a rewarded probabilistic learning task and measured individual trait hedonic capacity (the ability to experience pleasure) with the temporal experience of pleasure scale questionnaire. Results: As expected, the participants developed a response bias toward the most rewarded stimulus (rich stimulus). Reaction time and accuracy for the rich stimulus were respectively shorter and higher as compared to the less rewarded stimulus (lean stimulus). Active or sham stimulation did not seem to influence the outcome. However, when taking into account individual trait hedonic capacity, we found an early significant increase in the response bias only after active iTBS. The higher the individual's trait hedonic capacity, the more the response bias toward the rich stimulus increased after the active stimulation. Conclusion: When taking into account trait hedonic capacity, one active iTBS session over the left DLPFC improved reward responsiveness in healthy male participants with higher hedonic capacity. This suggests that individual differences in hedonic capacity may influence the effects of iTBS on the reward system. PMID:27378888

  17. Electrophysiological and Anatomical Correlates of Spinal Cord Optical Coherence Tomography.

    PubMed

    Giardini, Mario E; Zippo, Antonio G; Valente, Maurizio; Krstajic, Nikola; Biella, Gabriele E M

    2016-01-01

    Despite the continuous improvement in medical imaging technology, visualizing the spinal cord poses severe problems due to structural or incidental causes, such as small access space and motion artifacts. In addition, positional guidance on the spinal cord is not commonly available during surgery, with the exception of neuronavigation techniques based on static pre-surgical data and of radiation-based methods, such as fluoroscopy. A fast, bedside, intraoperative real-time imaging, particularly necessary during the positioning of endoscopic probes or tools, is an unsolved issue. The objective of our work, performed on experimental rats, is to demonstrate potential intraoperative spinal cord imaging and probe guidance by optical coherence tomography (OCT). Concurrently, we aimed to demonstrate that the electromagnetic OCT irradiation exerted no particular effect at the neuronal and synaptic levels. OCT is a user-friendly, low-cost and endoscopy-compatible photonics-based imaging technique. In particular, by using a Fourier-domain OCT imager, operating at 850 nm wavelength and scanning transversally with respect to the spinal cord, we have been able to: 1) accurately image tissue structures in an animal model (muscle, spine bone, cerebro-spinal fluid, dura mater and spinal cord), and 2) identify the position of a recording microelectrode approaching and inserting into the cord tissue 3) check that the infrared radiation has no actual effect on the electrophysiological activity of spinal neurons. The technique, potentially extendable to full three-dimensional image reconstruction, shows prospective further application not only in endoscopic intraoperative analyses and for probe insertion guidance, but also in emergency and adverse situations (e.g. after trauma) for damage recognition, diagnosis and fast image-guided intervention. PMID:27050096

  18. A Low-Cost iPhone-Assisted Augmented Reality Solution for the Localization of Intracranial Lesions

    PubMed Central

    Zhu, RuYuan; Chen, XiaoLei; Zhang, Jun

    2016-01-01

    Background Precise location of intracranial lesions before surgery is important, but occasionally difficult. Modern navigation systems are very helpful, but expensive. A low-cost solution that could locate brain lesions and their surface projections in augmented reality would be beneficial. We used an iPhone to partially achieve this goal, and evaluated its accuracy and feasibility in a clinical neurosurgery setting. Methodology/Principal Findings We located brain lesions in 35 patients, and using an iPhone, we depicted the lesion’s surface projection onto the skin of the head. To assess the accuracy of this method, we pasted computed tomography (CT) markers surrounding the depicted lesion boundaries on the skin onto 15 patients. CT scans were then performed with or without contrast enhancement. The deviations (D) between the CT markers and the actual lesion boundaries were measured. We found that 97.7% of the markers displayed a high accuracy level (D ≤ 5mm). In the remaining 20 patients, we compared our iPhone-based method with a frameless neuronavigation system. Four check points were chosen on the skin surrounding the depicted lesion boundaries, to assess the deviations between the two methods. The integrated offset was calculated according to the deviations at the four check points. We found that for the supratentorial lesions, the medial offset between these two methods was 2.90 mm and the maximum offset was 4.2 mm. Conclusions/Significance This low-cost, image-based, iPhone-assisted, augmented reality solution is technically feasible, and helpful for the localization of some intracranial lesions, especially shallow supratentorial intracranial lesions of moderate size. PMID:27454518

  19. Evoked potentials in large-scale cortical networks elicited by TMS of the visual cortex

    PubMed Central

    Grossman, Emily D.; Srinivasan, Ramesh

    2011-01-01

    Single pulses of transcranial magnetic stimulation (TMS) result in distal and long-lasting oscillations, a finding directly challenging the virtual lesion hypothesis. Previous research supporting this finding has primarily come from stimulation of the motor cortex. We have used single-pulse TMS with simultaneous EEG to target seven brain regions, six of which belong to the visual system [left and right primary visual area V1, motion-sensitive human middle temporal cortex, and a ventral temporal region], as determined with functional MRI-guided neuronavigation, and a vertex “control” site to measure the network effects of the TMS pulse. We found the TMS-evoked potential (TMS-EP) over visual cortex consists mostly of site-dependent theta- and alphaband oscillations. These site-dependent oscillations extended beyond the stimulation site to functionally connected cortical regions and correspond to time windows where the EEG responses maximally diverge (40, 200, and 385 ms). Correlations revealed two site-independent oscillations ∼350 ms after the TMS pulse: a theta-band oscillation carried by the frontal cortex, and an alpha-band oscillation over parietal and frontal cortical regions. A manipulation of stimulation intensity at one stimulation site (right hemisphere V1-V3) revealed sensitivity to the stimulation intensity at different regions of cortex, evidence of intensity tuning in regions distal to the site of stimulation. Together these results suggest that a TMS pulse applied to the visual cortex has a complex effect on brain function, engaging multiple brain networks functionally connected to the visual system with both invariant and site-specific spatiotemporal dynamics. With this characterization of TMS, we propose an alternative to the virtual lesion hypothesis. Rather than a technique that simulates lesions, we propose TMS generates natural brain signals and engages functional networks. PMID:21715670

  20. Three-dimensional reconstructed computed tomography-magnetic resonance fusion image-based preoperative planning for surgical procedures for spinal lipoma or tethered spinal cord after myelomeningocele repair.

    PubMed

    Bamba, Yohei; Nonaka, Masahiro; Nakajima, Shin; Yamasaki, Mami

    2011-01-01

    Surgical procedures for spinal lipoma or tethered spinal cord after myelomeningocele (MMC) repair are often difficult and complicated, because the anatomical structures can be deformed in complex and unpredictable ways. Imaging helps the surgeon understand the patient's spinal anatomy. Whereas two-dimensional images provide only limited information for surgical planning, three-dimensional (3D) reconstructed computed tomography (CT)-magnetic resonance (MR) fusion images produce clearer representations of the spinal regions. Here we describe simple and quick methods for obtaining 3D reconstructed CT-MR fusion images for preoperative planning of surgical procedures using the iPlan(®) cranial (BrainLAB AG, Feldkirchen, Germany) neuronavigation software. 3D CT images of the vertebral bone were combined with heavily T(2)-weighted MR images of the spinal cord, lipoma, cerebrospinal fluid (CSF) space, and nerve root through a process of fusion, segmentation, and reconstruction of the 3D images. We also used our procedure called "Image Overlay" to directly project the 3D reconstructed image onto the body surface using an LED projector. The final reconstructed 3D images took 10-30 minutes to obtain, and provided the surgeon with a representation of the individual pathological structures, so enabled the design of effective surgical plans, even in patients with bony deformity such as scoliosis. None of the 19 patients treated based on our 3D reconstruction method has had neurological complications, except for CSF leakage. This 3D reconstructed imaging method, combined with Image Overlay, improves the visual understanding of complicated surgical situations, and should improve surgical efficiency and outcome. PMID:21613771

  1. Frameless stereotactic neurosurgery: two steps towards the Holy Grail of surgical navigation.

    PubMed

    Eljamel, M S

    1999-01-01

    The holy grail of surgical navigation is to provide precise continuous feedback during surgery about the target and its surrounding structures. The first step was the ability of hardware and software technology to allow patient-to-image registration using a multi-potentiometer position-sensing articulated arm system. We used such a system (OAS; Radionics, Burlington, Mass., USA) in 169 consecutive patients with common intracranial lesions. We achieved a mean application accuracy of 2.5 mm, which was sufficiently reliable for most neurosurgical procedures. However, to get the feedback information, the surgeon has to look away from the operative field to the workstation monitor. As psychological studies of manual workers including surgeons indicated that performance is better when the worker is looking in a downward gaze at his hands, the natural progression was to project feedback information between the eyes and the hands. Therefore, the second step was to link tracking technology to the surgical microscope with head-up display. We used such a system (SMN-Zeiss, Germany) in 65 consecutive patients with a mean application accuracy of 1.4 mm. This was again sufficiently reliable for neuronavigation. The head-up display provided continuous feedback to the surgeon about the target, risk zones and areas of interest without the need to interrupt the procedure to get such information. Furthermore, the use of the focal length of SMN with autofocus to perform the registration improved the application accuracy of this technology. The ability of the software to process all MRI sequences (T(1), T(2), MPR and CISS) allowed us to use a variety of image sequences to delineate the lesion more exquisitely. PMID:10853063

  2. Bringing transcranial mapping into shape: Sulcus-aligned mapping captures motor somatotopy in human primary motor hand area.

    PubMed

    Raffin, Estelle; Pellegrino, Giovanni; Di Lazzaro, Vincenzo; Thielscher, Axel; Siebner, Hartwig Roman

    2015-10-15

    Motor representations express some degree of somatotopy in human primary motor hand area (M1HAND), but within-M1HAND corticomotor somatotopy has been difficult to study with transcranial magnetic stimulation (TMS). Here we introduce a "linear" TMS mapping approach based on the individual shape of the central sulcus to obtain mediolateral corticomotor excitability profiles of the abductor digiti minimi (ADM) and first dorsal interosseus (FDI) muscles. In thirteen young volunteers, we used stereotactic neuronavigation to stimulate the right M1HAND with a small eight-shaped coil at 120% of FDI resting motor threshold. We pseudorandomly stimulated six targets located on a straight mediolateral line corresponding to the overall orientation of the central sulcus with a fixed coil orientation of 45° to the mid-sagittal line (STRAIGHT-450FIX) or seven targets in the posterior part of the crown of the central sulcus following the bending of the central sulcus (CURVED). CURVED mapping employed a fixed (CURVED-450FIX) or flexible coil orientation producing always a current perpendicular to the sulcal wall (CURVED-900FLEX). During relaxation, CURVED but not STRAIGHT mapping revealed distinct corticomotor excitability peaks in M1HAND with the excitability maximum of ADM located medially to the FDI maximum. This mediolateral somatotopy was still present during tonic contraction of the ADM or FDI. During ADM contraction, cross-correlation between the spatial excitability profiles of ADM and FDI was lowest for CURVED-900FLEX. Together, the results show that within-M1HAND somatotopy can be readily probed with linear TMS mapping aligned to the sulcal shape. Sulcus-aligned linear mapping will benefit non-invasive studies of representational plasticity in human M1HAND. PMID:26188259

  3. Possible pitfalls in the diagnostic of progressive multifocal leukoencephalopathy.

    PubMed

    Zivanovic, Milanka; Savšek, Lina; Poljak, Mario; Popovic, Mara

    2016-01-01

    The most accurate diagnosis of clinically suspected progressive multifocal leukoencephalopathy (PML) is made by neuronavigated needle brain biopsy and microscopic examination of the specimen confirming typical morphological features of the disease and, additionally, using immunohistochemistry (IHC) for detection of early viral proteins of the etiologic agent - polyoma virus JC (JCV). Due to the small biopsy volume, this approach can sometimes fail to confirm the clinical diagnosis of PML, as demonstrated by the presented clinical case. To check the reliability of using only IHC, we additionally tested 6 archival cases from our institute using IHC, in-situ hybridization (ISH) and real-time polymerase chain reaction (PCR). In the presented case, both biopsy and autopsy material were tested, in three archival cases only biopsy material and in the remaining cases post-mortem brain tissue was available. IHC (Anti-SV40 T antigen, mAb Pab416) was negative in 3 samples, in another 3 fewer than 10 cells per one ×20 microscopic field were positive. In our study, ISH proved to be a more sensitive method for JCV detection than IHC, being positive in all cases. Out of 7 tested specimens, realtime PCR failed to confirm the presence of JCV in 1 specimen, which was the oldest brain autopsy of an AIDS patient. Our study demonstrated that, especially when confronted with borderline clinical suspicion of PML and when only a small biopsy specimen is available, a combination of at least two different methods for JCV detection should be considered, preferably IHC with one of the available molecular methods. PMID:26754416

  4. Conscious brain-to-brain communication in humans using non-invasive technologies.

    PubMed

    Grau, Carles; Ginhoux, Romuald; Riera, Alejandro; Nguyen, Thanh Lam; Chauvat, Hubert; Berg, Michel; Amengual, Julià L; Pascual-Leone, Alvaro; Ruffini, Giulio

    2014-01-01

    Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. PMID:25137064

  5. Musical training-induced functional reorganization of the adult brain: functional magnetic resonance imaging and transcranial magnetic stimulation study on amateur string players.

    PubMed

    Kim, Dong-Eog; Shin, Min-Jung; Lee, Kyoung-Min; Chu, Kon; Woo, Sung Ho; Kim, Young Ro; Song, Eun-Cheol; Lee, Jun-Won; Park, Seong-Ho; Roh, Jae-Kyu

    2004-12-01

    We used the combined technique of functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) to observe changes that occur in adult brains after the practice of stringed musical instruments. We carried out fMRI on eight volunteers (aged 20-22 years): five novices and three individuals who had discontinued practice for more than 5 years. The motor paradigm contained a repetitive lift-abduction/fall-adduction movement of the left/right little finger, carried out with maximum efforts without pacing. The sensory paradigm was to stimulate the same little finger using a string. In parallel to the fMRI acquisition, TMS motor maps for the little finger were obtained using a frameless stereotactic neuronavigation system. After the baseline study, each participant began to learn a stringed instrument. Newly developed fMRI activations for the left little finger were observed 6 months after practice at multiple brain regions including inferior parietal lobule, premotor area (PMA), left precuneus, right anterior superior temporal gyrus, and posterior middle temporal gyrus. In contrast, new activations were rarely observed for the right little finger. The TMS study revealed new motor representation sites for the left little finger in the PMA or supplementary motor area (SMA). Unexpectedly, TMS motor maps for the right little finger were reduced significantly. Among new fMRI activations for sensory stimuli of the left little finger, the cluster of highest activation was located in the SMA. Collectively, these data provide insight into orchestrated reorganization of the sensorimotor and temporal association cortices contributing to the skillful fingering and musical processing after the practice of playing stringed instruments. PMID:15449354

  6. Phase reversal technique decreases cortical stimulation time during motor mapping.

    PubMed

    Simon, Mirela V; Sheth, Sameer A; Eckhardt, Christine A; Kilbride, Ronan D; Braver, Diana; Williams, Ziv; Curry, William; Cahill, Dan; Eskandar, Emad N

    2014-06-01

    Neurophysiologic mapping of the primary motor cortex (PMC) is commonly used in supratentorial surgery. Electrical cortical stimulation is guided by anatomic landmarks towards the precentral gyrus, with recording of the triggered primary motor responses (TPMR) in the contralateral hemibody. Thus, factors such as distortion of the pericentral anatomy, small surgical fields, brain shifts and miscalibrated neuronavigational systems may lengthen the process and result in unnecessary stimulations, increasing the probability of triggering seizures. We hypothesized that central sulcus localization via the median somatosensory evoked potentials phase reversal technique (MSSEP PRT) accurately guides the surgeon, resulting in prompt identification of the PMC with minimal electrical stimulation. Multivariate Cox regression was used to study the impact of MSSEP PRT on time spent performing electrical cortical stimulation to TPMR. The analysis was adjusted for presence of increased cortical excitability, high motor thresholds, lesions close to PMC and fMRI data, in 100 consecutive standardized motor mapping procedures for brain tumor resection and epilepsy surgery. Phase reversal and change morphology of the recorded somatosensory evoked potentials quadrupled (hazard ratio [HR] 4.13, p<0.0001) and doubled (HR 2.14, p=0.02) the rate of obtaining TPMR, respectively. A 1mA increase in motor threshold decreased the rate by 9% (HR 0.91, p=0.0002). Afterdischarges triggered before TPMR and lesions in close proximity to PMC decreased the rate of TPMR by 76% (HR 0.23, p<0.0001) and 48% (HR 0.52, p=0.04), respectively. Informative PRT decreases stimulation time. Afterdischarges triggered before TPMR, high motor thresholds and lesions close to the PMC increase it. PMID:24679940

  7. Internal Maxillary Artery-Middle Cerebral Artery Bypass: Infratemporal Approach for Subcranial-Intracranial (SC-IC) Bypass

    PubMed Central

    Nossek, Erez; Costantino, Peter D.; Eisenberg, Mark; Dehdashti, Amir R.; Setton, Avi; Chalif, David J.; Ortiz, Rafael A.

    2014-01-01

    BACKGROUND: Internal maxillary artery (IMax)–middle cerebral artery (MCA) bypass has been recently described as an alternative to cervical extracranial-intracranial bypass. This technique uses a “keyhole” craniectomy in the temporal fossa that requires a technically challenging end-to-side anastomosis. OBJECTIVE: To describe a lateral subtemporal craniectomy of the middle cranial fossa floor to facilitate wide exposure of the IMax to facilitate bypass. METHODS: Orbitozygomatic osteotomy is used followed by frontotemporal craniotomy and subsequently laterotemporal fossa craniectomy, reaching its medial border at a virtual line connecting the foramen rotundum and foramen ovale. The IMax was identified by using established anatomic landmarks, neuronavigation, and micro Doppler probe (Mizuho Inc. Tokyo, Japan). Additionally, we studied the approach in a cadaveric specimen in preparation for microsurgical bypass. RESULTS: There were 4 cases in which the technique was used. One bypass was performed for flow augmentation in a hypoperfused hemisphere. The other 3 were performed as part of treatment paradigms for giant middle cerebral artery aneurysms. Vein grafts were used in all patients. The proximal anastomosis was performed in an end-to-side fashion in 1 patient and end-to-end in 3 patients. Intraoperative graft flow measured with the Transonic flow probe ranged from 20 to 60 mL/min. Postoperative angiography demonstrated good filling of the graft with robust distal flow in all cases. All patients tolerated the procedure well. CONCLUSION: IMax to middle cerebral artery subcranial-intracranial bypass is safe and efficacious. The laterotemporal fossa craniectomy technique resulted in reliable identification and wide exposure of the IMax, facilitating the proximal anastomosis. ABBREVIATIONS: EC-IC, extracranial-intracranial IMax, internal maxillary artery MCA, middle cerebral artery SC-IC, subcranial-intracranial STA, superficial temporal artery PMID:24618804

  8. Advances in diagnosis and treatment of trigeminal neuralgia

    PubMed Central

    Montano, Nicola; Conforti, Giulio; Di Bonaventura, Rina; Meglio, Mario; Fernandez, Eduardo; Papacci, Fabio

    2015-01-01

    Various drugs and surgical procedures have been utilized for the treatment of trigeminal neuralgia (TN). Despite numerous available approaches, the results are not completely satisfying. The need for more contemporaneous drugs to control the pain attacks is a common experience. Moreover, a number of patients become drug resistant, needing a surgical procedure to treat the neuralgia. Nonetheless, pain recurrence after one or more surgical operations is also frequently seen. These facts reflect the lack of the precise understanding of the TN pathogenesis. Classically, it has been related to a neurovascular compression at the trigeminal nerve root entry-zone in the prepontine cistern. However, it has been evidenced that in the pain onset and recurrence, various neurophysiological mechanisms other than the neurovascular conflict are involved. Recently, the introduction of new magnetic resonance techniques, such as voxel-based morphometry, diffusion tensor imaging, three-dimensional time-of-flight magnetic resonance angiography, and fluid attenuated inversion recovery sequences, has provided new insight about the TN pathogenesis. Some of these new sequences have also been used to better preoperatively evidence the neurovascular conflict in the surgical planning of microvascular decompression. Moreover, the endoscopy (during microvascular decompression) and the intraoperative computed tomography with integrated neuronavigation (during percutaneous procedures) have been recently introduced in the challenging cases. In the last few years, efforts have been made in order to better define the optimal target when performing the gamma knife radiosurgery. Moreover, some authors have also evidenced that neurostimulation might represent an opportunity in TN refractory to other surgical treatments. The aim of this work was to review the recent literature about the pathogenesis, diagnosis, and medical and surgical treatments, and discuss the significant advances in all these fields

  9. A Pilot Study of EEG Source Analysis Based Repetitive Transcranial Magnetic Stimulation for the Treatment of Tinnitus

    PubMed Central

    Wang, Hui; Li, Bei; Feng, Yanmei; Cui, Biao; Wu, Hongmin; Shi, Haibo; Yin, Shankai

    2015-01-01

    Objective Repetitive Transcranial Magnetic Stimulation (rTMS) is a novel therapeutic tool to induce a suppression of tinnitus. However, the optimal target sites are unknown. We aimed to determine whether low-frequency rTMS induced lasting suppression of tinnitus by decreasing neural activity in the cortex, navigated by high-density electroencephalogram (EEG) source analysis, and the utility of EEG for targeting treatment. Methods In this controlled three-armed trial, seven normal hearing patients with tonal tinnitus received a 10-day course of 1-Hz rTMS to the cortex, navigated by high-density EEG source analysis, to the left temporoparietal cortex region, and to the left temporoparietal with sham stimulation. The Tinnitus handicap inventory (THI) and a visual analog scale (VAS) were used to assess tinnitus severity and loudness. Measurements were taken before, and immediately, 2 weeks, and 4 weeks after the end of the interventions. Results Low-frequency rTMS decreased tinnitus significantly after active, but not sham, treatment. Responders in the EEG source analysis-based rTMS group, 71.4% (5/7) patients, experienced a significant reduction in tinnitus loudness, as evidenced by VAS scores. The target site of neuronal generators most consistently associated with a positive response was the frontal lobe in the right hemisphere, sourced using high-density EEG equipment, in the tinnitus patients. After left temporoparietal rTMS stimulation, 42.8% (3/7) patients experienced a decrease in tinnitus loudness. Conclusions Active EEG source analysis based rTMS resulted in significant suppression in tinnitus loudness, showing the superiority of neuronavigation-guided coil positioning in dealing with tinnitus. Non-auditory areas should be considered in the pathophysiology of tinnitus. This knowledge in turn can contribute to investigate the pathophysiology of tinnitus. PMID:26430749

  10. Near Real-Time Computer Assisted Surgery for Brain Shift Correction Using Biomechanical Models

    PubMed Central

    Pheiffer, Thomas S.; Simpson, Amber L.; Weis, Jared A.; Thompson, Reid C.; Miga, Michael I.

    2014-01-01

    Conventional image-guided neurosurgery relies on preoperative images to provide surgical navigational information and visualization. However, these images are no longer accurate once the skull has been opened and brain shift occurs. To account for changes in the shape of the brain caused by mechanical (e.g., gravity-induced deformations) and physiological effects (e.g., hyperosmotic drug-induced shrinking, or edema-induced swelling), updated images of the brain must be provided to the neuronavigation system in a timely manner for practical use in the operating room. In this paper, a novel preoperative and intraoperative computational processing pipeline for near real-time brain shift correction in the operating room was developed to automate and simplify the processing steps. Preoperatively, a computer model of the patient’s brain with a subsequent atlas of potential deformations due to surgery is generated from diagnostic image volumes. In the case of interim gross changes between diagnosis, and surgery when reimaging is necessary, our preoperative pipeline can be generated within one day of surgery. Intraoperatively, sparse data measuring the cortical brain surface is collected using an optically tracked portable laser range scanner. These data are then used to guide an inverse modeling framework whereby full volumetric brain deformations are reconstructed from precomputed atlas solutions to rapidly match intraoperative cortical surface shift measurements. Once complete, the volumetric displacement field is used to update, i.e., deform, preoperative brain images to their intraoperative shifted state. In this paper, five surgical cases were analyzed with respect to the computational pipeline and workflow timing. With respect to postcortical surface data acquisition, the approximate execution time was 4.5 min. The total update process which included positioning the scanner, data acquisition, inverse model processing, and image deforming was ∼ 11–13 min. In

  11. Non-invasive Transcranial Magnetic Stimulation (TMS) of the Motor Cortex for Neuropathic Pain—At the Tipping Point?

    PubMed Central

    Treister, Roi; Lang, Magdalena; Klein, Max M.; Oaklander, Anne Louise

    2013-01-01

    The term “neuropathic pain” (NP) refers to chronic pain caused by illnesses or injuries that damage peripheral or central pain-sensing neural pathways to cause them to fire inappropriately and signal pain without cause. Neuropathic pain is common, complicating diabetes, shingles, HIV, and cancer. Medications are often ineffective or cause various adverse effects, so better approaches are needed. Half a century ago, electrical stimulation of specific brain regions (neuromodulation) was demonstrated to relieve refractory NP without distant effects, but the need for surgical electrode implantation limited use of deep brain stimulation. Next, electrodes applied to the dura outside the brain’s surface to stimulate the motor cortex were shown to relieve NP less invasively. Now, electromagnetic induction permits cortical neurons to be stimulated entirely non-invasively using transcranial magnetic stimulation (TMS). Repeated sessions of many TMS pulses (rTMS) can trigger neuronal plasticity to produce long-lasting therapeutic benefit. Repeated TMS already has US and European regulatory approval for treating refractory depression, and multiple small studies report efficacy for neuropathic pain. Recent improvements include “frameless stereotactic” neuronavigation systems, in which patients’ head MRIs allow TMS to be applied to precise underlying cortical targets, minimizing variability between sessions and patients, which may enhance efficacy. Transcranial magnetic stimulation appears poised for the larger trials necessary for regulatory approval of a NP indication. Since few clinicians are familiar with TMS, we review its theoretical basis and historical development, summarize the neuropathic pain trial results, and identify issues to resolve before large-scale clinical trials. PMID:24228166

  12. Effects of a common transcranial direct current stimulation (tDCS) protocol on motor evoked potentials found to be highly variable within individuals over 9 testing sessions.

    PubMed

    Horvath, Jared Cooney; Vogrin, Simon J; Carter, Olivia; Cook, Mark J; Forte, Jason D

    2016-09-01

    Transcranial direct current stimulation (tDCS) uses a weak electric current to modulate neuronal activity. A neurophysiologic outcome measure to demonstrate reliable tDCS modulation at the group level is transcranial magnetic stimulation engendered motor evoked potentials (MEPs). Here, we conduct a study testing the reliability of individual MEP response patterns following a common tDCS protocol. Fourteen participants (7m/7f) each underwent nine randomized sessions of 1 mA, 10 min tDCS (3 anode; 3 cathode; 3 sham) delivered using an M1/orbito-frontal electrode montage (sessions separated by an average of ~5.5 days). Fifteen MEPs were obtained prior to, immediately following and in 5 min intervals for 30 min following tDCS. TMS was delivered at 130 % resting motor threshold using neuronavigation to ensure consistent coil localization. A number of non-experimental variables were collected during each session. At the individual level, considerable variability was seen among different testing sessions. No participant demonstrated an excitatory response ≥20 % to all three anodal sessions, and no participant demonstrated an inhibitory response ≥20 % to all three cathodal sessions. Intra-class correlation revealed poor anodal and cathodal test-retest reliability [anode: ICC(2,1) = 0.062; cathode: ICC(2,1) = 0.055] and moderate sham test-retest reliability [ICC(2,1) = 0.433]. Results also revealed no significant effect of tDCS at the group level. Using this common protocol, we found the effects of tDCS on MEP amplitudes to be highly variable at the individual level. In addition, no significant effects of tDCS on MEP amplitude were found at the group level. Future studies should consider utilizing a more strict experimental protocol to potentially account for intra-individual response variations. PMID:27150317

  13. Conscious Brain-to-Brain Communication in Humans Using Non-Invasive Technologies

    PubMed Central

    Grau, Carles; Ginhoux, Romuald; Riera, Alejandro; Nguyen, Thanh Lam; Chauvat, Hubert; Berg, Michel; Amengual, Julià L.; Pascual-Leone, Alvaro; Ruffini, Giulio

    2014-01-01

    Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. PMID:25137064

  14. Indocyanine green as an adjunct for resection of insular gliomas

    PubMed Central

    Shah, Abhidha; Rangarajan, Vithal; Kaswa, Amol; Jain, Sonal; Goel, Atul

    2016-01-01

    Objective: Many controversies exist regarding the extent of resection for insular gliomas and the timing of resection. Several techniques and adjuncts are used to maximize safety during resection of these tumors. We describe the use of indocyanine green (ICG) to identify the branches of the middle cerebral artery and discuss its utility to increase safety for resection for insular gliomas. Materials and Methods: Five patients with insular gliomas were surgically treated by the authors from June 2013 to June 2014. The patients presented with complaints of either a headache or recurring episodes of convulsions. All the patients were operated with the aid of neuronavigation and tractography. The long perforating branches of the middle cerebral artery course through the insula and pass onward to supply the corona radiata. It is essential to preserve these vessels to prevent postoperative neurological deficits. ICG (Aurogreen) was used to identify and preserve the long perforating arteries of the middle cerebral artery. Results: ICG dye correctly identified the long perforating branches of the middle cerebral artery and easily distinguished these vessels from the short perforating branches. All the branches of the middle cerebral artery that coursed through the tumor and had an onward course were preserved in all the patients. Only one patient developed a transient right sided hemiparesis that had improved at follow-up. Conclusions: Surgery for insular gliomas is challenging due to its location adjacent to eloquent areas, important white fiber tracts and the course of the middle cerebral artery within it. ICG is useful to identify and preserve the long perforating branches of the middle cerebral artery that course through the tumor and traverse onward to supply the corona radiata. PMID:27366256

  15. Time Course of Corticospinal Excitability and Autonomic Function Interplay during and Following Monopolar tDCS

    PubMed Central

    Santarnecchi, Emiliano; Feurra, Matteo; Barneschi, Federico; Acampa, Maurizio; Bianco, Giovanni; Cioncoloni, David; Rossi, Alessandro; Rossi, Simone

    2014-01-01

    While polarity-specific after-effects of monopolar transcranial direct current stimulation (tDCS) on corticospinal excitability are well-documented, modulation of vital parameters due to current spread through the brainstem is still a matter of debate, raising potential concerns about its use through the general public, as well as for neurorehabilitation purposes. We monitored online and after-effects of monopolar tDCS (primary motor cortex) in 10 healthy subjects by adopting a neuronavigated transcranial magnetic stimulation (TMS)/tDCS combined protocol. Motor evoked potentials (MEPs) together with vital parameters [e.g., blood pressure, heart-rate variability (HRV), and sympathovagal balance] were recorded and monitored before, during, and after anodal, cathodal, or sham tDCS. Ten MEPs, every 2.5-min time windows, were recorded from the right first dorsal interosseous (FDI), while 5-min epochs were used to record vital parameters. The protocol included 15 min of pre-tDCS and of online tDCS (anodal, cathodal, or sham). After-effects were recorded for 30 min. We showed a polarity-independent stabilization of cortical excitability level, a polarity-specific after-effect for cathodal and anodal stimulation, and an absence of persistent excitability changes during online stimulation. No significant effects on vital parameters emerged both during and after tDCS, while a linear increase in systolic/diastolic blood pressure and HRV was observed during each tDCS condition, as a possible unspecific response to experimental demands. Taken together, current findings provide new insights on the safety of monopolar tDCS, promoting its application both in research and clinical settings. PMID:25101009

  16. Usefulness of navigated O-arm® in a teaching center for spinal trauma

    PubMed Central

    Agrawal, Deepak

    2016-01-01

    Background: There is a relatively high incidence of screw misplacement during spinal instrumentation due to distortion of normal anatomy following spinal trauma. Aims and Objectives: To evaluate and share the initial experience with the use of neuro-navigated 3D O-arm® (Medtronic, USA) as compared to traditional 2D fluoroscopy in atrauma center in India. Materials and Methods: In this retrospective study, consecutive patients of spinal injury who underwent screw fixation under O-arm guidance over nine-month period (July 2010 till March 2011) were evaluated for accuracy of screw placement. An equal number of consecutive patients prior to March 2011 who underwent screw fixation in 2D fluoroscopy were included for comparison. Patient demographics and radiology were reviewed and spinal injury was assessed using the ASIA grading in both the groups. Screw placement was assessed by postoperative CT scans of the relevant spine and accuracy of screw placement and breach of the medial or lateral cortex of the pedicle were recorded for each case. Results: In the O-arm group, there were 57 patients in whom 210 screws were inserted. None of the patients had screw mal-placement. In 2D fluoroscopy group, 57 patients had 268 screws insertions. 10 (3.73%) screws were found to be malpositioned in the postoperative CT scans (8 in thoracic spine and 2 in odontoid fractures). The malposition rate was highly significant in 2D fluoroscopy thoracolumbar (P = 0.0015) subgroup. One patient had neurological deterioration and three patients required repositioning of the screws. Conclusion: In a teaching center with multiple surgeons, the O-arm® imaging ensures accurate placement of screws as compared to traditional 2D fluoroscopy. PMID:27366260

  17. Modeling transcranial magnetic stimulation from the induced electric fields to the membrane potentials along tractography-based white matter fiber tracts

    NASA Astrophysics Data System (ADS)

    De Geeter, Nele; Dupré, Luc; Crevecoeur, Guillaume

    2016-04-01

    Objective. Transcranial magnetic stimulation (TMS) is a promising non-invasive tool for modulating the brain activity. Despite the widespread therapeutic and diagnostic use of TMS in neurology and psychiatry, its observed response remains hard to predict, limiting its further development and applications. Although the stimulation intensity is always maximum at the cortical surface near the coil, experiments reveal that TMS can affect deeper brain regions as well. Approach. The explanation of this spread might be found in the white matter fiber tracts, connecting cortical and subcortical structures. When applying an electric field on neurons, their membrane potential is altered. If this change is significant, more likely near the TMS coil, action potentials might be initiated and propagated along the fiber tracts towards deeper regions. In order to understand and apply TMS more effectively, it is important to capture and account for this interaction as accurately as possible. Therefore, we compute, next to the induced electric fields in the brain, the spatial distribution of the membrane potentials along the fiber tracts and its temporal dynamics. Main results. This paper introduces a computational TMS model in which electromagnetism and neurophysiology are combined. Realistic geometry and tissue anisotropy are included using magnetic resonance imaging and targeted white matter fiber tracts are traced using tractography based on diffusion tensor imaging. The position and orientation of the coil can directly be retrieved from the neuronavigation system. Incorporating these features warrants both patient- and case-specific results. Significance. The presented model gives insight in the activity propagation through the brain and can therefore explain the observed clinical responses to TMS and their inter- and/or intra-subject variability. We aspire to advance towards an accurate, flexible and personalized TMS model that helps to understand stimulation in the connected

  18. Screw Placement Accuracy and Outcomes Following O-Arm-Navigated Atlantoaxial Fusion: A Feasibility Study

    PubMed Central

    Smith, Jacob D.; Jack, Megan M.; Harn, Nicholas R.; Bertsch, Judson R.; Arnold, Paul M.

    2015-01-01

    Study Design Case series of seven patients. Objective C2 stabilization can be challenging due to the complex anatomy of the upper cervical vertebrae. We describe seven cases of C1–C2 fusion using intraoperative navigation to aid in the screw placement at the atlantoaxial (C1–C2) junction. Methods Between 2011 and 2014, seven patients underwent posterior atlantoaxial fusion using intraoperative frameless stereotactic O-arm Surgical Imaging and StealthStation Surgical Navigation System (Medtronic, Inc., Minneapolis, Minnesota, United States). Outcome measures included screw accuracy, neurologic status, radiation dosing, and surgical complications. Results Four patients had fusion at C1–C2 only, and in the remaining three, fixation extended down to C3 due to anatomical considerations for screw placement recognized on intraoperative imaging. Out of 30 screws placed, all demonstrated minimal divergence from desired placement in either C1 lateral mass, C2 pedicle, or C3 lateral mass. No neurovascular compromise was seen following the use of intraoperative guided screw placement. The average radiation dosing due to intraoperative imaging was 39.0 mGy. All patients were followed for a minimum of 12 months. All patients went on to solid fusion. Conclusion C1–C2 fusion using computed tomography-guided navigation is a safe and effective way to treat atlantoaxial instability. Intraoperative neuronavigation allows for high accuracy of screw placement, limits complications by sparing injury to the critical structures in the upper cervical spine, and can help surgeons make intraoperative decisions regarding complex pathology. PMID:27190736

  19. Cerebellar brain inhibition in the target and surround muscles during voluntary tonic activation.

    PubMed

    Panyakaew, Pattamon; Cho, Hyun Joo; Srivanitchapoom, Prachaya; Popa, Traian; Wu, Tianxia; Hallett, Mark

    2016-04-01

    Motor surround inhibition is the neural mechanism that selectively favours the contraction of target muscles and inhibits nearby muscles to prevent unwanted movements. This inhibition was previously reported at the onset of a movement, but not during a tonic contraction. Cerebellar brain inhibition (CBI) is reduced in active muscles during tonic activation; however, it has not been studied in the surround muscles. CBI was evaluated in the first dorsal interosseus (FDI) muscle as the target muscle, and the abductor digiti minimi, flexor carpi radialis and extensor carpi radialis muscles as surround muscles, during rest and tonic activation of the FDI muscle in 21 subjects. Cerebellar stimulation was performed under magnetic resonance imaging-guided neuronavigation targeting lobule VIII of the cerebellar hemisphere. Stimulus intensities for cerebellar stimulation were based on the resting motor cortex threshold (RMT) and adjusted for the depth difference between the cerebellar and motor cortices. We used 90-120% of the adjusted RMT as the conditioning stimulus intensity during rest. The intensity that generated the best CBI at rest in the FDI muscle was selected for use during tonic activation. During selective tonic activation of the FDI muscle, CBI was significantly reduced only for the FDI muscle, and not for the surround muscles. Unconditioned motor evoked potential sizes were increased in all muscles during FDI muscle tonic activation as compared with rest, despite background electromyography activity increasing only for the FDI muscle. Our study suggests that the cerebellum may play an important role in selective tonic finger movement by reducing its inhibition in the motor cortex only for the relevant agonist muscle. PMID:26900871

  20. Transsphenoidal Resection of Sellar Tumors Using High-Field Intraoperative Magnetic Resonance Imaging

    PubMed Central

    Szerlip, Nicholas J.; Zhang, Yi-Chen; Placantonakis, Dimitris G.; Goldman, Marc; Colevas, Kara B.; Rubin, David G.; Kobylarz, Eric J.; Karimi, Sasan; Girotra, Monica; Tabar, Viviane

    2011-01-01

    There has been increasing experience in the utilization of intraoperative magnetic resonance imaging (iMRI) for intracranial surgery. Despite this trend, only a few U.S centers have examined the use of this technology for transsphenoidal resection of tumors of the sella. We present the largest series in North America examining the role of iMRI for pituitary adenoma resection. We retrospectively reviewed our institutional experience of 59-patients who underwent transsphenoidal procedures for sellar and suprasellar tumors with iMRI guidance. Of these, 52 patients had a histological diagnosis of pituitary adenoma. The technical results of this subgroup were examined. A 1.5-T iMRI was integrated with the BrainLAB (Feldkirchen, Germany) neuronavigation system. The majority (94%) of tumors in our series were macroadenomas. Seventeen percent of tumors were confined to the sella, 49% had suprasellar extensions without involvement of the cavernous sinus, 34% had frank cavernous sinus invasion. All patients underwent at least one iMRI, and 19% required one or more additional sets of intraoperative imaging. In 58% of patients, iMRI led to the surgeon attempting more resection. A gross total resection was obtained in 67% of the patients with planned total resections. There was one case of permanent postoperative diabetes insipidus and no other instances of new hormone replacement. In summary, iMRI was most useful for tumors of the sella with and without suprasellar extension where the information from the iMRI extended the complete resection rate from 40 to 72% and 55 to 88%, respectively. As one would expect, it did not substantially increase the rate of resection of tumors with cavernous sinus invasion. Overall, iMRI was particularly useful in guiding resection safely, aiding in clinical decision making, and allowing identification and preservation of the pituitary stalk and normal pituitary gland. Limitations of the iMRI include a need for additional personnel and training

  1. (68)Ga-Pentixafor-PET/CT for Imaging of Chemokine Receptor 4 Expression in Glioblastoma.

    PubMed

    Lapa, Constantin; Lückerath, Katharina; Kleinlein, Irene; Monoranu, Camelia Maria; Linsenmann, Thomas; Kessler, Almuth F; Rudelius, Martina; Kropf, Saskia; Buck, Andreas K; Ernestus, Ralf-Ingo; Wester, Hans-Jürgen; Löhr, Mario; Herrmann, Ken

    2016-01-01

    Chemokine receptor-4 (CXCR4) has been reported to be overexpressed in glioblastoma (GBM) and to be associated with poor survival. This study investigated the feasibility of non-invasive CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using the radiolabelled chemokine receptor ligand (68)Ga-Pentixafor. 15 patients with clinical suspicion on primary or recurrent glioblastoma (13 primary, 2 recurrent tumors) underwent (68)Ga-Pentixafor-PET/CT for assessment of CXCR4 expression prior to surgery. O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) PET/CT images were available in 11/15 cases and were compared visually and semi-quantitatively (SUVmax, SUVmean). Tumor-to-background ratios (TBR) were calculated for both PET probes. (68)Ga-Pentixafor-PET/CT results were also compared to histological CXCR4 expression on neuronavigated surgical samples. (68)Ga-Pentixafor-PET/CT was visually positive in 13/15 cases with SUVmean and SUVmax of 3.0±1.5 and 3.9±2.0 respectively. Respective values for (18)F-FET were 4.4±2.0 (SUVmean) and 5.3±2.3 (SUVmax). TBR for SUVmean and SUVmax were higher for (68)Ga-Pentixafor than for (18)F-FET (SUVmean 154.0±90.7 vs. 4.1±1.3; SUVmax 70.3±44.0 and 3.8±1.2, p<0.01), respectively. Histological analysis confirmed CXCR4 expression in tumor areas with high (68)Ga-Pentixafor uptake; regions of the same tumor without apparent (68)Ga-Pentixafor uptake showed no or low receptor expression. In this pilot study, (68)Ga-Pentixafor retention has been observed in the vast majority of glioblastoma lesions and served as readout for non-invasive determination of CXCR4 expression. Given the paramount importance of the CXCR4/SDF-1 axis in tumor biology, (68)Ga-Pentixafor-PET/CT might prove a useful tool for sensitive, non-invasive in-vivo quantification of CXCR4 as well as selection of patients who might benefit from CXCR4-directed therapy. PMID:26909116

  2. 68Ga-Pentixafor-PET/CT for Imaging of Chemokine Receptor 4 Expression in Glioblastoma

    PubMed Central

    Lapa, Constantin; Lückerath, Katharina; Kleinlein, Irene; Monoranu, Camelia Maria; Linsenmann, Thomas; Kessler, Almuth F.; Rudelius, Martina; Kropf, Saskia; Buck, Andreas K.; Ernestus, Ralf-Ingo; Wester, Hans-Jürgen; Löhr, Mario; Herrmann, Ken

    2016-01-01

    Chemokine receptor-4 (CXCR4) has been reported to be overexpressed in glioblastoma (GBM) and to be associated with poor survival. This study investigated the feasibility of non-invasive CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using the radiolabelled chemokine receptor ligand 68Ga-Pentixafor. 15 patients with clinical suspicion on primary or recurrent glioblastoma (13 primary, 2 recurrent tumors) underwent 68Ga-Pentixafor-PET/CT for assessment of CXCR4 expression prior to surgery. O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET) PET/CT images were available in 11/15 cases and were compared visually and semi-quantitatively (SUVmax, SUVmean). Tumor-to-background ratios (TBR) were calculated for both PET probes. 68Ga-Pentixafor-PET/CT results were also compared to histological CXCR4 expression on neuronavigated surgical samples. 68Ga-Pentixafor-PET/CT was visually positive in 13/15 cases with SUVmean and SUVmax of 3.0±1.5 and 3.9±2.0 respectively. Respective values for 18F-FET were 4.4±2.0 (SUVmean) and 5.3±2.3 (SUVmax). TBR for SUVmean and SUVmax were higher for 68Ga-Pentixafor than for 18F-FET (SUVmean 154.0±90.7 vs. 4.1±1.3; SUVmax 70.3±44.0 and 3.8±1.2, p<0.01), respectively. Histological analysis confirmed CXCR4 expression in tumor areas with high 68Ga-Pentixafor uptake; regions of the same tumor without apparent 68Ga-Pentixafor uptake showed no or low receptor expression. In this pilot study, 68Ga-Pentixafor retention has been observed in the vast majority of glioblastoma lesions and served as readout for non-invasive determination of CXCR4 expression. Given the paramount importance of the CXCR4/SDF-1 axis in tumor biology, 68Ga-Pentixafor-PET/CT might prove a useful tool for sensitive, non-invasive in-vivo quantification of CXCR4 as well as selection of patients who might benefit from CXCR4-directed therapy. PMID:26909116

  3. Application of contrast-enhanced T1-weighted MRI-based 3D reconstruction of the dural tail sign in meningioma resection.

    PubMed

    You, Binsheng; Cheng, Yanhao; Zhang, Jian; Song, Qimin; Dai, Chao; Heng, Xueyuan; Fei, Chang

    2016-07-01

    OBJECT The goal of this study was to investigate the significance of contrast-enhanced T1-weighted (T1W) MRI-based 3D reconstruction of dural tail sign (DTS) in meningioma resection. METHODS Between May 2013 and August 2014, 18 cases of convexity and parasagittal meningiomas showing DTS on contrast-enhanced T1W MRI were selected. Contrast-enhanced T1W MRI-based 3D reconstruction of DTS was conducted before surgical treatment. The vertical and anteroposterior diameters of DTS on the contrast-enhanced T1W MR images and 3D reconstruction images were measured and compared. Surgical incisions were designed by referring to the 3D reconstruction and MR images, and then the efficiency of the 2 methods was evaluated with assistance of neuronavigation. RESULTS Three-dimensional reconstruction of DTS can reveal its overall picture. In most cases, the DTS around the tumor is uneven, whereas the DTS around the dural vessels presents longer extensions. There was no significant difference (p > 0.05) between the vertical and anteroposterior diameters of DTS measured on the contrast-enhanced T1W MR and 3D reconstruction images. The 3D images of DTS were more intuitive, and the overall picture of DTS could be revealed in 1 image, which made it easier to design the incision than by using the MR images. Meanwhile, assessment showed that the incisions designed using 3D images were more accurate than those designed using MR images (ridit analysis by SAS, F = 7.95; p = 0.008). Pathological examination showed that 34 dural specimens (except 2 specimens from 1 tumor) displayed tumor invasion. The distance of tumor cell invasion was 1.0-21.6 mm (5.4 ± 4.41 mm [mean ± SD]). Tumor cell invasion was not observed at the dural resection margin in all 36 specimens. CONCLUSIONS Contrast-enhanced T1W MRI-based 3D reconstruction can intuitively and accurately reveal the size and shape of DTS, and thus provides guidance for designing meningioma incisions. PMID:26654184

  4. Improved nTMS- and DTI-derived CST tractography through anatomical ROI seeding on anterior pontine level compared to internal capsule.

    PubMed

    Weiss, Carolin; Tursunova, Irada; Neuschmelting, Volker; Lockau, Hannah; Nettekoven, Charlotte; Oros-Peusquens, Ana-Maria; Stoffels, Gabriele; Rehme, Anne K; Faymonville, Andrea Maria; Shah, N Jon; Langen, Karl Josef; Goldbrunner, Roland; Grefkes, Christian

    2015-01-01

    Imaging of the course of the corticospinal tract (CST) by diffusion tensor imaging (DTI) is useful for function-preserving tumour surgery. The integration of functional localizer data into tracking algorithms offers to establish a direct structure-function relationship in DTI data. However, alterations of MRI signals in and adjacent to brain tumours often lead to spurious tracking results. We here compared the impact of subcortical seed regions placed at different positions and the influences of the somatotopic location of the cortical seed and clinical co-factors on fibre tracking plausibility in brain tumour patients. The CST of 32 patients with intracranial tumours was investigated by means of deterministic DTI and neuronavigated transcranial magnetic stimulation (nTMS). The cortical seeds were defined by the nTMS hot spots of the primary motor area (M1) of the hand, the foot and the tongue representation. The CST originating from the contralesional M1 hand area was mapped as intra-individual reference. As subcortical region of interests (ROI), we used the posterior limb of the internal capsule (PLIC) and/or the anterior inferior pontine region (aiP). The plausibility of the fibre trajectories was assessed by a-priori defined anatomical criteria. The following potential co-factors were analysed: Karnofsky Performance Scale (KPS), resting motor threshold (RMT), T1-CE tumour volume, T2 oedema volume, presence of oedema within the PLIC, the fractional anisotropy threshold (FAT) to elicit a minimum amount of fibres and the minimal fibre length. The results showed a higher proportion of plausible fibre tracts for the aiP-ROI compared to the PLIC-ROI. Low FAT values and the presence of peritumoural oedema within the PLIC led to less plausible fibre tracking results. Most plausible results were obtained when the FAT ranged above a cut-off of 0.105. In addition, there was a strong effect of somatotopic location of the seed ROI; best plausibility was obtained for the

  5. Intracerebroventricular Pain Treatment with Analgesic Mixtures including Ziconotide for Intractable Pain.

    PubMed

    Staquet, Héléne; Dupoiron, Denis; Nader, Edmond; Menei, Philippe

    2016-07-01

    Intracerebroventricular (ICV) administration of opioids for control of intractable cancer pain has been used since 1982. We present here our experience of intracerebroventricular administration of pain treatments including ziconotide associated with morphine and ropivacaine for patients resistant to a conventional approach, with nociceptive, neuropathic, or mixed pain. These clinical cases were conducted with patients suffering from refractory pain, more than 6/10 on a numerical pain rating scale (NPRS) while on high-dose medical treatment and/or intolerance with significant side effects from oral medication. The baseline study visit included a physical examination and an assessment of pain intensity on a NPRS. Under general anesthesia, a neuronavigation device was used to place the catheter on the floor of the third ventricle, supported by an endoscope. Then, drugs were injected in the cerebroventricular system, through a pump (external or subcutaneous). The primary objective was to measure pain evaluation with ICV treatment after a complete withdrawal of other medications.Four patients were enrolled: 3 with intractable cancer pain and one with central neuropathic pain. The median NPRS at baseline was 9.5 [8.5; 19]. The mean NPRS after one month was 3.5 [3; 4.5]. Ziconotide was initiated at 0.48 µg/d and up to a median of 1.2 µg/d [1.0; 1.56]. The median dose of morphine and ropivacaine used initially was respectively 0.36 mg/d [0.24; 0.66] up to 0.6 mg/d [0.45; 4.63] and 1.2 mg/d [0; 2.4] up to 2.23 mg/d [1.2; 3.35]. Minor side effects were initially observed but transiently. One psychiatric agitation required discontinuation of ziconotide infusion. For intractable pain, using ziconotide by intracerebroventricular infusion seems safe and efficient, specifically for chronic neoplastic pain of cervicocephalic, thoracic, or diffuse origin and also for pain arising from a central neuropathic mechanism. PMID:27454282

  6. The future of cerebral surgery: a kaleidoscope of opportunities.

    PubMed

    Elder, James B; Hoh, Daniel J; Oh, Bryan C; Heller, A Chris; Liu, Charles Y; Apuzzo, Michael L J

    2008-06-01

    The emerging future of cerebral surgery will witness the refined evolution of current techniques, as well as the introduction of numerous novel concepts. Clinical practice and basic science research will benefit greatly from their application. The sum of these efforts will result in continued minimalism and improved accuracy and efficiency of neurosurgical diagnostic and therapeutic methodologies.Initially, the refinement of current technologies will further enhance various aspects of cerebral surgery. Advances in computing power and information technology will speed data acquisition, storage, and transfer. Miniaturization of current devices will impact diverse areas, such as modulation of endoscopy and endovascular techniques. The increased penetrance of surgical technologies such as stereotactic radiosurgery, neuronavigation, intraoperative imaging, and implantable electrodes for neurodegenerative disorders and epilepsy will enhance the knowledge and experience in these areas and facilitate refinements and advances in these technologies. Further into the future, technologies that are currently relatively remote to surgical events will fundamentally alter the complexity and scale at which a neurological disease may be treated or investigated. Seemingly futuristic concepts will become ubiquitous in the daily experience of the neurosurgeon. These include diverse fields such as nanotechnology, virtual reality, and robotics. Ultimately, combining advances in multiple fields will yield progress in diverse realms such as brain tumor therapy, neuromodulation for psychiatric diseases, and neuroprosthetics. Operating room equipment and design will benefit from each of the aforementioned advances. In this work, we discuss new developments in three parts. In Part I, concepts in minimalism important for future cerebral surgery are discussed. These include concrete and abstract ideas in miniaturization, as well as recent and future work in microelectromechanical systems and