scholarly journals Compact Rotational Ultrasound Probe Holder for Brachytherapy

2017 ◽  
Author(s):  
Filip Jelínek ◽  
Gernot Kronreif ◽  
Cor van de Wardt
Keyword(s):  
Haptic Feedback ◽  
Organs At Risk ◽  
Transrectal Ultrasound ◽  
Safety Margin ◽  
Optical Tracking ◽  
Fine Tuning ◽  
Seamless Integration ◽  
Tumor Spread ◽  
Limited Range Of Motion ◽  
Probe Holder

Image-guided adaptive brachytherapy (IGABT) is a promising method for precise targeting and treatment of cervical and prostate cancer where one can adapt the radiation delivery according to tumor spread and organs at risk (OAR). The currently developing procedural modality incorporating optical tracking and transrectal ultrasound (TRUS) for superior soft tissue contrast, later combined with CT data, will likely develop into a readily affordable option, as the use of MRI will become unnecessary [1]. This is especially relevant for developing countries (mainly in SE Africa and S America) where the MRI scanners are scarce and the occurrence specifically of cervical cancer is the highest worldwide [2]. In brachytherapy, the procedure requires either the use of an active source (cervix) or implantation of radioactive seeds (prostate) in an accurate way as to enable sufficient safety margin with respect to the OAR. The sources irradiate the tissue of interest through gynecological (GYN) applicators (inserted internally) as well as hollow needles guided by either these applicators or prostate templates (positioned externally). Due to the localized use of several devices, an uninterrupted verification of source or needle placement can only be provided if the TRUS probe scans the volume of interest without much movement, likely leading to physical interference. Hence, the longitudinal ultrasound (US) array is used to obtain a 3D-US volume using a rotational sweep. The use of a TRUS probe for an automatic US image reconstruction requires the probe to be housed in a motorized unit, a so-called stepper or a probe holder, which should ideally be integrated seamlessly into the overall procedure without impeding the established workflow or imposing any unnecessary space and time restrictions within the operating room (OR). Seamless integration should also mean minimal assembly steps required by the OR staff, whether nurses or surgeons themselves, as well as the possibility to use the TRUS probe in a natural unrestricted way. More specifically, when housed in the stepper, the probe’s geometry and weight should not be exaggerated as to allow enough haptic feedback for the surgeon when guiding the probe through the bodily cavities or probing for any unnatural or pathological tissue. Examples of conventional brachytherapy steppers include Mikrostepper MST 200 (GfM, Riedstadt-Leeheim, Germany), Transperineal Stepper (D&K Technologies, Barum, Germany), AccuCARE™ Classic Stepper (Civco, Coralville, IA, USA), STP 110 Precision™ Stepper (Best NOMOS, Pittsburgh, PA, USA), or OncoSelect Stepper equipped with EndoCavity Rotational Mover (Elekta, Veenendaal, NL). Each of these devices provides precise rotational and translational fine-tuning, motorized image acquisition as well as high positioning rigidity. Yet, in most cases, this is at the expense of their oversized dimensions, large mass often requiring a counterweight, limited range of motion or cumbersome handling. As a result, their overall usability is compromised, especially in applications requiring better haptic experience, such as an initial free-hand scan during GYN brachytherapy. Hence, the aim of this paper is to present a novel, compact and versatile solution compensating for the aforementioned limitations and enabling seamless integration.

scholarly journals Systematic Review of Focal Prostate Brachytherapy and the Future Implementation of Image-Guided Prostate HDR Brachytherapy Using MR-Ultrasound Fusion

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
M. Sean Peach ◽  
Daniel M. Trifiletti ◽  
Bruce Libby
Keyword(s):  
At Risk ◽  
Organs At Risk ◽  
Transrectal Ultrasound ◽  
Prostate Brachytherapy ◽  
Hdr Brachytherapy ◽  
Clinical Papers ◽  
Image Guided ◽  
Focal Treatment ◽  
Definitive Therapy

Prostate cancer is the most common malignancy found in North American and European men and the second most common cause of cancer related death. Since the practice of PSA screening has become common the disease is most often found early and can have a long indolent course. Current definitive therapy treats the whole gland but has considerable long-term side effects. Focal therapies may be able to target the cancer while decreasing dose to organs at risk. Our objective was to determine if focal prostate brachytherapy could meet target objectives while permitting a decrease in dose to organs at risk in a way that would allow future salvage treatments. Further, we wanted to determine if focal treatment results in less toxicity. Utilizing the Medline repository, dosimetric papers comparing whole gland to partial gland brachytherapy and clinical papers that reported toxicity of focal brachytherapy were selected. A total of 9 dosimetric and 6 clinical papers met these inclusion criteria. Together, these manuscripts suggest that focal brachytherapy may be employed to decrease dose to organs at risk with decreased toxicity. Of current technology, image-guided HDR brachytherapy using MRI registered to transrectal ultrasound offers the flexibility and efficiency to achieve such focal treatments.

scholarly journals Acoustic signal analysis of instrument–tissue interaction for minimally invasive interventions

2020 ◽  
Vol 15 (5) ◽  
pp. 771-779
Author(s):  
Daniel Ostler ◽  
Matthias Seibold ◽  
Jonas Fuchtmann ◽  
Nicole Samm ◽  
Hubertus Feussner ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Haptic Feedback ◽  
Automated Analysis ◽  
Acoustic Signals ◽  
Feature Representation ◽  
Fatty Tissue ◽  
Surgical Performance ◽  
Data Set ◽  
Tissue Interaction ◽  
Limited Range Of Motion

Abstract Purpose Minimally invasive surgery (MIS) has become the standard for many surgical procedures as it minimizes trauma, reduces infection rates and shortens hospitalization. However, the manipulation of objects in the surgical workspace can be difficult due to the unintuitive handling of instruments and limited range of motion. Apart from the advantages of robot-assisted systems such as augmented view or improved dexterity, both robotic and MIS techniques introduce drawbacks such as limited haptic perception and their major reliance on visual perception. Methods In order to address the above-mentioned limitations, a perception study was conducted to investigate whether the transmission of intra-abdominal acoustic signals can potentially improve the perception during MIS. To investigate whether these acoustic signals can be used as a basis for further automated analysis, a large audio data set capturing the application of electrosurgery on different types of porcine tissue was acquired. A sliding window technique was applied to compute log-mel-spectrograms, which were fed to a pre-trained convolutional neural network for feature extraction. A fully connected layer was trained on the intermediate feature representation to classify instrument–tissue interaction. Results The perception study revealed that acoustic feedback has potential to improve the perception during MIS and to serve as a basis for further automated analysis. The proposed classification pipeline yielded excellent performance for four types of instrument–tissue interaction (muscle, fascia, liver and fatty tissue) and achieved top-1 accuracies of up to 89.9%. Moreover, our model is able to distinguish electrosurgical operation modes with an overall classification accuracy of 86.40%. Conclusion Our proof-of-principle indicates great application potential for guidance systems in MIS, such as controlled tissue resection. Supported by a pilot perception study with surgeons, we believe that utilizing audio signals as an additional information channel has great potential to improve the surgical performance and to partly compensate the loss of haptic feedback.

scholarly journals Hybrid TRUS/CT with optical tracking for target delineation in image-guided adaptive brachytherapy for cervical cancer

2020 ◽  
Vol 196 (11) ◽  
pp. 983-992
Author(s):  
Stéphanie Smet ◽  
Nicole Nesvacil ◽  
Johannes Knoth ◽  
Alina Sturdza ◽  
Dina Najjari-Jamal ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Interobserver Variability ◽  
Imaging Modality ◽  
Locally Advanced ◽  
Transrectal Ultrasound ◽  
Optical Tracking ◽  
Conformity Index ◽  
Reference Structure ◽  
Image Guided ◽  
The Mean

Abstract Objective To prospectively compare the interobserver variability of combined transrectal ultrasound (TRUS)/computed tomography (CT)- vs. CT only- vs. magnetic resonance imaging (MRI) only-based contouring of the high-risk clinical target volume (CTVHR) in image-guided adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC). Methods Five patients with LACC (FIGO stages IIb–IVa) treated with radiochemotherapy and IGABT were included. CT, TRUS, and T2-weighted MRI images were performed after brachytherapy applicator insertion. 3D-TRUS image acquisition was performed with a customized ultrasound stepper device and software. Automatic applicator reconstruction using optical tracking was performed in the TRUS dataset and TRUS and CT images were fused with rigid image registration with the applicator as reference structure. The CTVHR (based on the GEC-ESTRO recommendations) was contoured by five investigators on the three modalities (CTVHR_CT, CTVHR_TRUS-CT, and CTVHR_MRI). A consensus reference CTVHR_MRI (MRIref) was defined for each patient. Descriptive statistics and overlap measures were calculated using RTslicer (SlicerRT Community and Percutaneous Surgery Laboratory, Queen’s University, Canada), comparing contours of every observer with one another and with the MRIref. Results The interobserver coefficient of variation was 0.18 ± 0.05 for CT, 0.10 ± 0.04 for TRUS-CT, and 0.07 ± 0.03 for MRI. Interobserver concordance in relation to the MRIref expressed by the generalized conformity index was 0.75 ± 0.04 for MRI, 0.51 ± 0.10 for TRUS-CT, and 0.48 ± 0.06 for CT. The mean CTVHR_CT volume of all observers was 71% larger than the MRIref volume, whereas the mean CTVHR_TRUS-CT volume was 15% larger. Conclusion Hybrid TRUS-CT as an imaging modality for contouring the CTVHR in IGABT for LACC is feasible and reproducible among multiple observers. TRUS-CT substantially reduces overestimation of the CTVHR volume of CT alone while maintaining similar interobserver variability.

scholarly journals Design and Analysis of a Symmetric Articulated Single-Port Laparoscopic Surgical Device

2017 ◽  
Author(s):  
Rohan Katoch ◽  
Boao Xia ◽  
Yoshinori Yamakawa ◽  
Jun Ueda ◽  
Hiroshi Honda
Keyword(s):  
Force Feedback ◽  
Haptic Feedback ◽  
Single Port ◽  
Operating Experience ◽  
Economic Benefits ◽  
Driving Mechanism ◽  
End Effector ◽  
Limited Range Of Motion ◽  
Functional Features ◽  
Laparoscopic Device

Laparoscopic surgery is a practice of minimally invasive surgery (MIS) performed in the abdominal area. Prior to surgery, instead of exposing the target region to air as in a typical conventional open surgery, “key holes” are opened for positioning ports, through which surgical tools (e.g. laparoscope, needle drivers, etc.) are inserted. MIS therefore minimizes trauma and reduces the risk of hemorrhaging and infection. MIS also generates economic benefits such as shorter hospitalization time for patients and better utilization of operating rooms and wards for hospitals. MIS procedures, however, require extra dexterity from surgeons: they must use instruments with little to none haptic feedback to remotely manipulate tissue within a limited range of motion, assisted by an indirect view from laparoscope. Such unintuitive operations not only require additional training, but also increase the risk of medical errors. Thus, the development of novel surgical devices that can provide a better operating experience will allow surgeons to deliver safer and more effective surgeries. At the advent of MIS only rigid straight laparoscopic instruments were available. Therefore, surgeons used multiple incisions to position the tools and achieve triangulation. In single port laparoscopic surgeries (SPLS), only one incision is made for positioning a port. Two rigid straight instruments inserted through one incision cannot provide sufficient triangulation for operations. Rigid bent, or articulated, instruments can achieve triangulation, but the tools must intersect at a point. The mapping to control the end-effector, therefore, must be inverted such that the right hand controls the left end-effector, and vice versa [1]. Given this inverted mapping, surgeons need to undergo extra training to intuitively control the end-effector, and greater attention is required toward operating the device, which can potentially detract from the ability of surgeons to focus on procedures. The disadvantage of an inverted mapping can be overcome by providing additional mobility with flexible tools and actuating structures [2]. For example, Transenterix has developed a flexible laparoscopic device which utilizes a cable-driven system for articulation of the end-effectors. However, using flexible elements as the driving mechanism can result in new problems such as diminished force feedback [3]. In 2015, a novel design of an articulated single port laparoscopic device was presented with 6 degrees of freedom (DOF). The system provides intuitive control, accurate force feedback, and sufficient manipulation for laparoscopic procedures. The design proposed in this paper keeps much of the functional features in the previous model, including 1:1 mapping and force feedback, while incorporating flexible hydraulic graspers. The articulated mechanism was redesigned to have a symmetrical structure, which is more intuitive to control and provides better operating angles for surgeons. Joint structures are redesigned for enhanced robustness and misalignment prevention. Kinematic analysis is presented for the proposed mechanisms, which is used to determine the manipulator workspace.

scholarly journals Low cost heads-up virtual reality (HUVR) with optical tracking and haptic feedback

2011 ◽  
Author(s):  
Todd Margolis ◽  
Thomas A. DeFanti ◽  
Greg Dawe ◽  
Andrew Prudhomme ◽  
Jurgen P. Schulze ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Haptic Feedback ◽  
Low Cost ◽  
Optical Tracking

The limits of human performance

2008 ◽  
Vol 44 ◽  
pp. 11-26 ◽  
Author(s):  
Ralph Beneke ◽  
Dieter Böning
Keyword(s):  
Human Performance ◽  
Safety Margin ◽  
Afferent Input ◽  
Metabolic Energy ◽  
Human Organism ◽  
Mechanical Resistance ◽  
As Doping ◽  
Gene And Protein Expression ◽  
Underlying Mechanisms ◽  
Biochemical Research

Human performance, defined by mechanical resistance and distance per time, includes human, task and environmental factors, all interrelated. It requires metabolic energy provided by anaerobic and aerobic metabolic energy sources. These sources have specific limitations in the capacity and rate to provide re-phosphorylation energy, which determines individual ratios of aerobic and anaerobic metabolic power and their sustainability. In healthy athletes, limits to provide and utilize metabolic energy are multifactorial, carefully matched and include a safety margin imposed in order to protect the integrity of the human organism under maximal effort. Perception of afferent input associated with effort leads to conscious or unconscious decisions to modulate or terminate performance; however, the underlying mechanisms of cerebral control are not fully understood. The idea to move borders of performance with the help of biochemicals is two millennia old. Biochemical findings resulted in highly effective substances widely used to increase performance in daily life, during preparation for sport events and during competition, but many of them must be considered as doping and therefore illegal. Supplements and food have ergogenic potential; however, numerous concepts are controversially discussed with respect to legality and particularly evidence in terms of usefulness and risks. The effect of evidence-based nutritional strategies on adaptations in terms of gene and protein expression that occur in skeletal muscle during and after exercise training sessions is widely unknown. Biochemical research is essential for better understanding of the basic mechanisms causing fatigue and the regulation of the dynamic adaptation to physical and mental training.

Fine-Tuning Futures

ASHA Leader ◽  
2017 ◽  
Vol 22 (6) ◽  
Author(s):  
Christi Miller
Keyword(s):  
Fine Tuning

Impairment Tutorial: Rating Tears of the Acetabular Labrum

2006 ◽  
Vol 11 (6) ◽  
pp. 4-7
Author(s):  
Charles N. Brooks ◽  
Richard E. Strain ◽  
James B. Talmage
Keyword(s):  
Magnetic Resonance ◽  
Hip Arthroscopy ◽  
Age Groups ◽  
Limited Range ◽  
Labral Repair ◽  
X Rays ◽  
Joint Stability ◽  
Acetabular Labrum ◽  
Complete Excision ◽  
Limited Range Of Motion

Abstract The primary function of the acetabular labrum, like that of the glenoid, is to deepen the socket and improve joint stability. Tears of the acetabular labrum are common in older adults but occur in all age groups and with equal frequency in males and females. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is silent about rating tears, partial or complete excision, or repair of the acetabular labrum. Provocative tests to detect acetabular labrum tears involve hip flexion and rotation; all rely on production of pain in the groin (typically), clicking, and/or locking with passive or active hip motions. Diagnostic tests or procedures rely on x-rays, conventional arthrography, computerized tomography, magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA), and hip arthroscopy. Hip arthroscopy is the gold standard for diagnosis but is the most invasive and most likely to result in complications, and MRA is about three times more sensitive and accurate in detecting acetabular labral tears than MRI alone. Surgical treatment for acetabular labrum tears usually consists of arthroscopic debridement; results tend to be better in younger patients. In general, an acetabular labral tear, partial labrectomy, or labral repair warrants a rating of 2% lower extremity impairment. Evaluators should avoid double dipping (eg, using both a Diagnosis-related estimates and limited range-of-motion tests).

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