Benoit M. Dawant

Vanderbilt University, Нашвилл, Michigan, United States

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Publications (342)472.25 Total impact


  • No preview · Article · Feb 2016 · Otology & Neurotology
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    ABSTRACT: HYPOTHESIS:: Electrode-to-modiolus distance is correlated with clinically programmed stimulation levels. BACKGROUND:: Conventional wisdom has long supposed a significant relationship between cochlear implant (CI) stimulation levels and electrode-to-modiolus distance; however, to date, no such formal investigation has been completed. Thus, the purpose of this project was to investigate the relationship between stimulation levels and electrode-to-modiolus distance. A strong correlation between the two would suggest that stimulation levels might be used to estimate electrode-to-modiolus geometry. METHODS:: Electrode-to-modiolus distance was determined via CT imaging using validated CI position analysis software in 137 implanted ears from the three manufacturers holding FDA approval in the United States. Analysis included 2,365 total electrodes, with 1,472 from precurved arrays. Distances were compared to clinically programmed C/M levels that were converted to charge units. RESULTS:: Mean modiolar distance with perimodiolar and lateral wall electrodes was 0.47 and 1.15?mm, respectively. Mean suprathreshold charge values were significantly different between each manufacturer. When combining all data, we found a moderate positive correlation (r?=?0.367, p?<?0.01) that was driven both by the different charge values across companies, and that the company with the highest mean charge values only offers straight electrode arrays. When grouped by electrode type, however, we found a weak correlation (r?=?0.12, p?<?0.01) for perimodiolar array electrodes only. When considering a single array type from any one manufacturer, only one was observed where distance mildly predicted charge. CONCLUSION:: Our results suggest that electrode distance minimally contributes to the current level required for suprathreshold stimulation. Copyright © 2015 by Otology & Neurotology, Inc. Image
    No preview · Article · Jan 2016 · Otology & Neurotology
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    ABSTRACT: OBJECTIVE:: To test the use of a novel, image-guided cochlear implant (CI) programming (IGCIP) technique on prelingually deafened, adult CI recipients. STUDY DESIGN:: Prospective unblinded study. SETTING:: Tertiary referral center. PATIENTS:: Twenty-six prelingually deafened adult CI recipients with 29 CIs (3 bilateral). INTERVENTION(S):: Temporal-bone CT scans were used as input to a series of semiautomated computer algorithms which estimate the location of electrodes in reference to the modiolus. This information was used to selectively deactivate suboptimally located electrodes, i.e., those for which the distance from the electrode to the modiolus was further than a neighboring electrode to the same site. Patients used the new IGCIP program exclusively for 3–5 weeks. MAIN OUTCOME MEASURE(S):: Minimum Speech Test Battery (MSTB), quality of life (QOL), and spectral modulation detection (SMD). RESULTS:: On average one-third of electrodes were deactivated. At the group level, no significant differences were noted for MSTB measures nor for QOL estimates. Average SMD significantly improved after IGCIP reprogramming, which is consistent with improved spatial selectivity. Using 95% confidence interval data for CNC, AzBio, and BKB-SIN at the individual level, 76 to 90% of subjects demonstrated equivocal or significant improvement. Ultimately 21 of 29 (72.41%) elected to keep the IGCIP map because of perceived benefit often substantiated by improvement on either MSTB, QOL, and/or SMD. CONCLUSIONS:: Knowledge of the geometric relationship between CI electrodes and the modiolus appears to be useful in adjusting CI maps in prelingually deafened adults. Long-term improvements may be observed resulting from improved spatial selectivity and spectral resolution. Copyright © 2015 by Otology & Neurotology, Inc. Image
    No preview · Article · Dec 2015 · Otology & Neurotology
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    Full-text · Dataset · Jul 2015
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    Yuan Liu · Benoit M Dawant
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    ABSTRACT: Localizing the anterior and posterior commissures (AC/PC) and the midsagittal plane (MSP) is crucial in stereotactic and functional neurosurgery, human brain mapping, and medical image processing. We present a learning-based method for automatic and efficient localization of these landmarks and the plane using regression forests. Given a point in an image, we first extract a set of multi-scale long-range contextual features. We then build random forests models to learn a nonlinear relationship between these features and the probability of the point being a landmark or in the plane. Three-stage coarse-to-fine models are trained for the AC, PC, and MSP separately using down-sampled by 4, down-sampled by 2, and the original images. Localization is per-formed hierarchically, starting with a rough estimation that is progressively refined. We evaluate our method using a leave-one-out approach with 100 clinical T1-weighted images and compare it to state-of-the-art methods including an atlas-based approach with six nonrigid registration algorithms and a model-based approach for the AC and PC, and a global sy-metry-based approach for the MSP. Our method results in an overall error of 0.55±0.30mm for AC, 0.56±0.28mm for PC, 1.08˚±0.66˚ in the plane's normal direction and 1.22±0.73 voxels in average distance for MSP; it performs significantly better than four registration algorithms and the model-based method for AC and PC, and the global symmetry-based method for MSP. We also evaluate the sensitivity of our method to image quality and parameter values. We show that it is robust to asymmetry, noise, and rotation. Computation time is 25 seconds.
    Full-text · Article · Jul 2015
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    ABSTRACT: Contemporary cochlear implant (CI) sound processors filter acoustic signals into different frequency bands and provide electrical stimulation to tonotopically distributed spiral ganglion nerve fibers via an electrode array which is blindly threaded into the cochlea during surgery. The final positions of the electrodes in relation to the nerve fibers are generally unknown, resulting in a unique electrode positioning for each patient. This is in part due to the variable length of the cochlea with respect to the physical insertion depth of the electrode array. Despite this, default frequency assignments are a common practice in clinical fitting procedures. Suboptimal electrode array placement, variations in insertion depth, and exact positioning and proximity of electrodes to nerve fibers can all result in a mismatch between the intended and actual pitch perception. This frequency mismatch holds potential for reducing the efficacy of the coded information to the auditory cortex and, consequently, limit speech recognition. The present study leverages image-guided procedures to determine the true location of individual electrodes with respect to the nerve fibers and proposes a patient-specific frequency assignment strategy which helps to minimize sub-optimal frequency-place mapping distortions in CIs. Prior research in this domain suggests that peak performance is achieved when the full acoustic range is mapped to the tonotopic map where analysis bands exactly match the tonotopic map of the cochlea. While patients adapt to minor mismatch over time, severe mismatch, as seen with shallow insertion, can result in significant spectral distortion (Başkent & Shannon, 2005) and hence limit the level of asymptotic performance as well as increase adaptation time (Fu et al., 2002). The proposed strategy utilizes pre and post implantation CT scans of recipients’ cochleae to determine precise spatial location of electrode contacts and the corresponding neural stimulation sites and thus generate an optimal user-customized frequency-place function which is used to derive frequency characteristics of the filterbanks. This is achieved by maximizing the frequency match at lower frequencies (frequency range of first three formants), and introducing mild compression as needed to avoid truncation (e.g., due to shallow insertion). Mid and high frequency bands are assigned conventional logarithmic filter spacing. The performance of the proposed strategy was evaluated with 42 normal hearing (NH) listeners using vocoder-simulations. The simulation data indicate significantly better speech recognitions scores than the default clinical mapping scheme on all measures. Preliminary investigation with one CI user indicates statistically significant improvement in speech recognition and perception scores relative to the clinical map in acute experiments. Lack of knowledge on the spatial relationship between electrodes and the stimulation sites has resulted in a generic one-size-fits-all frequency mapping paradigm with the hope that CI users will learn to adapt to the incorrect frequency locations of stimulation. The proposed solution optimizes the frequency-to-place mapping based on individual’s cochlear physiology and true location of electrodes. The data from the present study suggest that user customized frequency maps can potentially aid in achieving higher asymptotic performance and possibly faster adaptation to electric hearing. Başkent, D., and Shannon, R. V. (2005). "Interactions between cochlear implant electrode insertion depth and frequency-place mapping," The Journal of the Acoustical Society of America, 117 (3), 1405-1416. Fu, Q. J., Shannon, R. V., and Galvin III, J. J. (2002), "Perceptual learning following changes in the frequency-to-electrode assignment with the Nucleus-22 cochlear implant," The Journal of the Acoustical Society of America, 112 (4), 1664-1674.
    Full-text · Conference Paper · Jul 2015
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    ABSTRACT: To evaluate the relationship between intrascalar electrode location, electrode type (lateral wall, perimodiolar, and midscala), and angular insertion depth on residual hearing in cochlear implant (CI) recipients. Tertiary academic hospital. Adult CI patients with functional preoperative residual hearing with preoperative and postoperative CT scans. Audiological assessment after CI. Electrode location, angular insertion depth, residual hearing post-CI, and word scores with CI (consonant-nucleus-consonant [CNC]). Forty-five implants in 36 patients (9 bilateral) were studied. Thirty-eight electrode arrays (84.4%) were fully inserted in scala tympani (ST), 6 (13.3%) crossed from ST to scala vestibuli (SV), and 1 (2.2%) was completely in SV. Twenty-two of the 38 (57.9%) with full ST insertion maintained residual hearing at 1 month compared with 0 of the 7 (0%) with non-full ST insertion (p = 0.005). Three surgical approaches were used: cochleostomy (C) 6/44, extended round window (ERW) 8/44, and round window (RW) 30/44. C and ERW were small group to compare with RW approaches. However if we combine C + ERW, then RW has higher chance of full ST insertion (p = 0.014). Looking at the full ST group, neither age, sex, nor electrode type demonstrated statistically significant associations with hearing preservation (p = 0.646, p = 0.4, and p = 0.929, respectively). The median angular insertion depth was 429° (range, 373°-512°) with no significant difference between the hearing and nonhearing preserved groups (p = 0.287). Scalar excursion is a strong predictor of losing residual hearing. However, neither age, sex, electrode type, nor angular insertion depth was correlated with hearing preservation in the full ST group. Techniques to decrease the risk of electrode excursion from ST are likely to result in improved residual hearing and CI performance.
    Full-text · Article · Jul 2015 · Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology
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    ABSTRACT: Neurological diseases have a devastating impact on millions of individuals and their families. These diseases will continue to constitute a significant research focus for this century. The search for effective treatments and cures requires multiple teams of experts in clinical neurosciences, neuroradiology, engineering, and industry. Hence, the need to communicate a large amount of information with accuracy and precision is more necessary than ever for this specialty. In this paper, we present a distributed system that supports this vision, which we call the CranialVault Cloud (CranialCloud). It consists in a network of nodes, each with the capability to store and process data, that share the same spatial normalization processes, thus guaranteeing a common reference space. We detail and justify design choices, the architecture and functionality of individual nodes, the way these nodes interact, and how the distributed system can be used to support inter-institutional research. We discuss the current state of the system that gathers data for more than 1,600 patients and how we envision it to grow. We contend that the fastest way to find and develop promising treatments and cures is to permit teams of researchers to aggregate data, spatially normalize these data, and share them. The CranialVault system is a system that supports this vision.
    Full-text · Article · Apr 2015 · International Journal of Computer Assisted Radiology and Surgery
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    ABSTRACT: Multi-channel cochlear implants (CI) leverage frequency based cochlear tonotopic mapping to map acoustic information to the cochlear place of stimulation which is primarily determined by electrode locations. Despite the fact that electrode locations within the cochlea are unique to each patient, the acoustic frequencies assigned to the electrodes by the CI processor are determined generically, resulting in a mismatch between intended and actual pitch perception. This is known to be a limiting factor for hearing outcomes with CIs. In this study, we propose a novel, image-guided CI processor programming strategy to select more optimal, patient-customized frequency assignments. The performance of the proposed strategy was evaluated using vocoder-based simulations with ten normal hearing listeners. In our simulations, our strategy results in significantly better speech recognition scores than the standard clinical strategy.
    Full-text · Conference Paper · Apr 2015
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    ABSTRACT: Finding the optimal location for the implantation of the electrode in deep brain stimulation (DBS) surgery is crucial for maximizing the therapeutic benefit to the patient. Such targeting is challenging for several reasons, including anatomic variability between patients as well as the lack of consensus about the location of the optimal target. To compare the performance of popular manual targeting methods against a fully automatic nonrigid image registration-based approach. In 71 Parkinson disease subthalamic nucleus (STN)-DBS implantations, an experienced functional neurosurgeon selected the target manually using 3 different approaches: indirect targeting using standard stereotactic coordinates, direct targeting based on the patient magnetic resonance imaging, and indirect targeting relative to the red nucleus. Targets were also automatically predicted by using a leave-one-out approach to populate the CranialVault atlas with the use of nonrigid image registration. The different targeting methods were compared against the location of the final active contact, determined through iterative clinical programming in each individual patient. Targeting by using standard stereotactic coordinates corresponding to the center of the motor territory of the STN had the largest targeting error (3.69 mm), followed by direct targeting (3.44 mm), average stereotactic coordinates of active contacts from this study (3.02 mm), red nucleus-based targeting (2.75 mm), and nonrigid image registration-based automatic predictions using the CranialVault atlas (2.70 mm). The CranialVault atlas method had statistically smaller variance than all manual approaches. Fully automatic targeting based on nonrigid image registration with the use of the CranialVault atlas is as accurate and more precise than popular manual methods for STN-DBS. AC, anterior commissureDBS, deep brain stimulationPC, posterior commissurePD, Parkinson diseaseRN, red nucleusSTN, subthalamic nucleusTR, repetition time.
    No preview · Article · Mar 2015 · Neurosurgery
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    ABSTRACT: Accurate and reliable identification of thalamic nuclei is important for surgical interventions and neuroanatomical studies. This is a challenging task due to their small sizes and low intra-thalamic contrast in standard T1-weighted or T2-weighted images. Previously proposed techniques rely on diffusion imaging or functional imaging. These require additional scanning and suffer from the low resolution and signal-to-noise ratio in these images. In this paper, we aim to directly segment the thalamic nuclei in standard 3T T1-weighted images using shape models. We manually delineate the structures in high-field MR images and build high resolution shape models from a group of subjects. We then investigate if the nuclei locations can be inferred from the whole thalamus. To do this, we hierarchically fit joint models. We start from the entire thalamus and fit a model that captures the relation between the thalamus and large nuclei groups. This allows us to infer the boundaries of these nuclei groups and we repeat the process until all nuclei are segmented. We validate our method in a leave-one-out fashion with seven subjects by comparing the shape-based segmentations on 3T images to the manual contours. Results we have obtained for major nuclei (dice coefficients ranging from 0.57 to 0.88 and mean surface errors from 0.29mm to 0.72mm) suggest the feasibility of using such joint shape models for localization. This may have a direct impact on surgeries such as Deep Brain Stimulation procedures that require the implantation of stimulating electrodes in specific thalamic nuclei.
    Full-text · Conference Paper · Feb 2015
  • Yiyuan Zhao · Benoit M. Dawant · Jack H. Noble
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    ABSTRACT: Cochlear implants (CIs) are neural prosthetics that stimulate the auditory nerve pathways within the cochlea using an implanted electrode array to restore hearing. After implantation, the CI is programmed by an audiologist who determines which electrodes are active, i.e., the electrode configuration, and selects other stimulation settings. Recent clinical studies by our group have shown that hearing outcomes can be significantly improved by using an image-guided electrode configuration selection technique we have designed. Our goal in this work is to automate the electrode configuration selection step with the long term goal of developing a fully automatic system that can be translated to the clinic. Until now, the electrode configuration selection step has been performed by an expert with the assistance of image analysis-based estimates of the electrode-neural interface. To automatically determine the electrode configuration, we have designed an optimization approach and propose the use of a cost function with feature terms designed to interpret the image analysis data in a similar fashion as the expert. Further, we have designed an approach to select parameters in the cost function using our database of existing electrode configuration plans as training data. The results we present show that our automatic approach results in electrode configurations that are better or equally as good as manually selected configurations in over 80% of the cases tested. This method represents a crucial step towards clinical translation of our image-guided cochlear implant programming system.
    No preview · Conference Paper · Feb 2015
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    ABSTRACT: Background: Deep brain stimulation (DBS) of the globus pallidus internus is established as efficacious for dystonia, yet the optimal target within this structure is not well defined. Published evidence suggests that spatial normalization provides a better estimate of DBS lead location than traditional methods based on standard stereotactic coordinates. Methods: We retrospectively reviewed our pallidal implanted dystonia population. Patient imaging scans were morphed into an MRI atlas using a nonlinear image registration algorithm. Active contact locations were projected onto the atlas and clusters analyzed for the degree of variance in two groups: (1) good and poor responders and (2) cervical (CD) and generalized dystonia (GD). Results: The average active contact location between CD and GD good responders was distinct but not significantly different. The mean active contact for CD poor responders was significantly different from CD responders and GD poor responders in the dorsoventral direction. Conclusions: A normalized imaging space is arguably more accurate in visualizing postoperative leads. Despite some separation between groups, this data suggests there was not an optimal pallidal target for common dystonia patients. Degrees of variance overlapped due to a large degree of individual target variation. Patient selection may ultimately be the key to maximizing patient outcomes.
    No preview · Article · Dec 2014 · Stereotactic and Functional Neurosurgery
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    ABSTRACT: The cochlear implant (CI) has been labeled the most successful neural prosthesis. Despite this success, a significant number of CI recipients experience poor speech understanding, and, even among the best performers, restoration to normal auditory fidelity is rare. While significant research efforts have been devoted to improving stimulation strategies, few developments have led to significant hearing improvement over the past two decades. We have recently introduced image processing techniques that open a new direction for advancement in this field by making it possible, for the first time, to determine the position of implanted CI electrodes relative to the nerves they stimulate using computed tomography images. In this article, we present results of an image-guided, patient-customized approach to stimulation that utilizes the electrode position information our image processing techniques provide. This approach allows us to identify electrodes that cause overlapping stimulation patterns and to deactivate them from a patient's map. This individualized mapping strategy yields significant improvement in speech understanding in both quiet and noise as well as improved spectral resolution in the 68 adult CI recipients studied to date. Our results indicate that image guidance can improve hearing outcomes for many existing CI recipients without requiring additional surgery or the use of 'experimental' stimulation strategies, hardware or software. © 2014 S. Karger AG, Basel.
    No preview · Article · Nov 2014 · Audiology and Neurotology
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    ABSTRACT: Objectives/HypothesisThree surgical approaches: cochleostomy (C), round window (RW), and extended round window (ERW); and two electrodes types: lateral wall (LW) and perimodiolar (PM), account for the vast majority of cochlear implantations. The goal of this study was to analyze the relationship between surgical approach and electrode type with final intracochlear position of the electrode array and subsequent hearing outcomes. Study DesignComparative longitudinal study. Methods One hundred postlingually implanted adult patients were enrolled in the study. From the postoperative scan, intracochlear electrode location was determined and using rigid registration, transformed back to the preoperative computed tomography which had intracochlear anatomy (scala tympani and scala vestibuli) specified using a statistical shape model based on 10 microCT scans of human cadaveric cochleae. Likelihood ratio chi-square statistics were used to evaluate for differences in electrode placement with respect to surgical approach (C, RW, ERW) and type of electrode (LW, PM). ResultsElectrode placement completely within the scala tympani (ST) was more common for LW than were PM designs (89% vs. 58%; P<0.001). RW and ERW approaches were associated with lower rates of electrode placement outside the ST than was the cochleostomy approach (9%, 16%, and 63%, respectively; P<0.001). This pattern held true regardless of whether the implant was LW or PM. When examining electrode placement and hearing outcome, those with electrode residing completely within the ST had better consonant-nucleus-consonant word scores than did patients with any number of electrodes located outside the ST (P=0.045). Conclusion These data suggest that RW and ERW approaches and LW electrodes are associated with an increased likelihood of successful ST placement. Furthermore, electrode position entirely within the ST confers superior audiological outcomes. Level Of Evidence2b. Laryngoscope, 124:S1-S7, 2014
    Full-text · Article · Nov 2014 · The Laryngoscope
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    ABSTRACT: Introduction Post-operative programming of deep brain stimulation for movement disorders can be both time consuming and difficult, which can delay the optimal symptom control for the patient. Probabilistic maps of stimulation response could improve programming efficiency and optimization. Methods The clinically selected contacts of patients who had undergone ventral intermediate nucleus deep brain stimulation for the treatment of essential tremor at our institution were compared against contacts selected based on a probability map of symptom reduction built by populating data from a number of patients using non-rigid image registration. A subgroup of patients whose clinical contacts did not match the map-based selections prospectively underwent a tremor rating scale evaluation to compare the symptom relief achieved by the two options. Both the patient and video reviewer were blinded to the selection. Results 54% of the map-based and clinical contacts were an exact match retrospectively and were within one contact 83% of the time. In 5 of the 8 mismatched leads that were evaluated prospectively in a double blind fashion, the map-based contact showed equivalent or better tremor improvement than the clinically active contact. Conclusions This study suggests that probability maps of stimulation responses can assist in selecting the clinically optimal contact and increase the efficiency of programming.
    No preview · Article · Sep 2014 · Parkinsonism & Related Disorders
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    Yiyuan Zhao · Benoit M Dawant · Robert F Labadie · Jack H Noble
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    ABSTRACT: Cochlear Implants (CI) are surgically implanted neural prosthetic de-vices used to treat severe-to-profound hearing loss. Recent studies have sug-gested that hearing outcomes with CIs are correlated with the location where individual electrodes in the implanted electrode array are placed, but techniques proposed for determining electrode location have been too coarse and labor in-tensive to permit detailed analysis on large numbers of datasets. In this paper, we present a fully automatic snake-based method for accurately localizing CI electrodes in clinical post-implantation CTs. Our results show that average elec-trode localization errors with the method are 0.21 millimeters. These results in-dicate that our method could be used in future large scale studies to analyze the relationship between electrode position and hearing outcome, which potentially could lead to technological advances that improve hearing outcomes with CIs.
    Full-text · Conference Paper · Sep 2014
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    Yuan Liu · Benoit M Dawant
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    ABSTRACT: Identification of the anterior and posterior commissure is crucial in stereotactic and functional neurosurgery, human brain mapping, and medical image processing. We present a learning-based algorithm to automatically and rapidly localize these landmarks using random forests regression. Given a point in the image, we extract a set of multi-scale long-range textural features, and associate a probability for this point to be the landmark. We build random forests models to learn the relationship between the value of these features and the probability of a point to be a landmark point. Three-stage coarse-to-fine models are trained for AC and PC separately using down-sampled by 4, down-sampled by 2, and the original images. Testing is performed in a hierarchical approach to first obtain a rough estimation at the coarse level and then fine-tune the landmark position. We extensively evaluate our method in a leave-one-out fashion using a large dataset of 100 T1-weighted images. We also compare our method to the state-of-art AC/PC detection methods including an atlas-based approach with six well-established nonrigid registration algorithms and a publicly available implementation of a model-based approach. Our method results in an overall error of 0.84±0.41mm for AC, 0.83±0.36mm for PC and a maximum error of 2.04mm; it performs significantly better than the model-based AC/PC detection method we compare it to and better than three of the nonrigid registration methods. It is much faster than nonrigid registration methods.
    Full-text · Conference Paper · Aug 2014
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    ABSTRACT: Objective: Minimally-invasive image-guided approach to cochlear implantation (CI) involves drilling a narrow, linear tunnel to the cochlea. Reported herein is the first clinical implementation of this approach. Study Design: Prospective, cohort study. Methods: On preoperative CT, a safe linear trajectory through the facial recess targeting the scala tympani was planned. Intraoperatively, fiducial markers were bone-implanted, a second CT was acquired, and the trajectory was transferred from preoperative to intraoperative CT. A customized microstereotactic frame was rapidly designed and constructed to constrain a surgical drill along the desired trajectory. Following sterilization, the frame was employed to drill the tunnel to the middle ear. After lifting a tympanomeatal flap and performing a cochleostomy, the electrode array was threaded through the drilled tunnel and into the cochlea. Results: Eight of nine patients were successfully implanted using the proposed approach with six insertions completely within scala tympani. Traditional mastoidectomy was performed on one patient following difficulty threading the electrode array via the narrow tunnel. Other difficulties encountered included use of the back-up implant when an electrode was dislodged during threading via the tunnel, tip fold-over, and facial nerve paresis (House-Brackmann II/VII at 12 months) secondary to heat during drilling. Average time of intervention was 182±36 minutes. Conclusion: Minimally-invasive, image-guided CI is clinically achievable. Further clinical study is necessary to address technological difficulties during drilling and insertion and to assess potential benefits including decreased time of intervention, standardization of surgical intervention, and decreased tissue dissection potentially leading to shorter recovery and earlier implant activation.
    No preview · Article · Aug 2014 · The Laryngoscope
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    ABSTRACT: Identification of error in non-rigid registration is a critical problem in the medical image processing community. We recently proposed an algorithm that we call "Assessing Quality Using Image Registration Circuits" (AQUIRC) to identify non-rigid registration errors and have tested its performance using simulated cases. In this article, we extend our previous work to assess AQUIRC's ability to detect local non-rigid registration errors and validate it quantitatively at specific clinical landmarks, namely the Anterior Commissure (AC) and the Posterior Commissure (PC). To test our approach on a representative range of error we utilize 5 different registration methods and use 100 target images and 9 atlas images. Our results show that AQUIRC's measure of registration quality correlates with the true target registration error (TRE) at these selected landmarks with an R² = 0.542. To compare our method to a more conventional approach, we compute Local Normalized Correlation Coefficient (LNCC) and show that AQUIRC performs similarly. However, a multi-linear regression performed with both AQUIRC's measure and LNCC shows a higher correlation with TRE than correlations obtained with either measure alone, thus showing the complementarity of these quality measures. We conclude the article by showing that the AQUIRC algorithm can be used to reduce registration errors for all five algorithms.
    Full-text · Article · Jul 2014 · IEEE Transactions on Medical Imaging

Publication Stats

7k Citations
472.25 Total Impact Points

Institutions

  • 1970-2016
    • Vanderbilt University
      • • Department of Electrical Engineering and Computer Science
      • • Vanderbilt Institute of Imaging Science
      • • Department of Biomedical Engineering
      Нашвилл, Michigan, United States
  • 2013
    • University of Alabama at Birmingham
      • Department of Radiation Oncology
      Birmingham, Alabama, United States
  • 2006
    • Boston College, USA
      Boston, Massachusetts, United States
  • 1997
    • Stanford University
      Palo Alto, California, United States
  • 1993
    • Bridgestone Corporation
      Nashville, Tennessee, United States
  • 1988
    • University of Houston
      • Department of Electrical & Computer Engineering
      Houston, TX, United States