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1.
PLoS One ; 19(6): e0304743, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38917106

RESUMEN

This observational study aimed to evaluate the intra- and inter-operator reliability of a digital palpation device in measuring compressive stiffness of the patellar tendon at different knee angles in talent and elite volleyball players. Second aim was to examine differences in reliability when measuring at different knee angles, between dominant and non-dominant knees, between sexes, and with age. Two operators measured stiffness at the midpoint of the patellar tendon in 45 Dutch volleyball players at 0°, 45° and 90° knee flexion, on both the dominant and non-dominant side. We found excellent intra-operator reliability (ICC>0.979). For inter-operator reliability, significant differences were found in stiffness measured between operators (p<0.007). The coefficient of variance significantly decreased with increasing knee flexion (2.27% at 0°, 1.65% at 45° and 1.20% at 90°, p<0.001). In conclusion, the device appeared to be reliable when measuring compressive stiffness of the patellar tendon in elite volleyball players, especially at 90° knee flexion. Inter-operator reliability appeared to be questionable. More standardized positioning and measurement protocols seem necessary.


Asunto(s)
Palpación , Ligamento Rotuliano , Voleibol , Humanos , Voleibol/fisiología , Masculino , Femenino , Ligamento Rotuliano/fisiología , Palpación/instrumentación , Palpación/métodos , Reproducibilidad de los Resultados , Adulto Joven , Adulto , Rango del Movimiento Articular/fisiología , Articulación de la Rodilla/fisiología , Adolescente , Fenómenos Biomecánicos , Variaciones Dependientes del Observador
2.
Int J Comput Assist Radiol Surg ; 19(6): 1147-1155, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38598140

RESUMEN

PURPOSE: This paper evaluates user performance in telesurgical tasks with the da Vinci Research Kit (dVRK), comparing unilateral teleoperation, bilateral teleoperation with force sensors and sensorless force estimation. METHODS: A four-channel teleoperation system with disturbance observers and sensorless force estimation with learning-based dynamic compensation was developed. Palpation experiments were conducted with 12 users who tried to locate tumors hidden in tissue phantoms with their fingers or through handheld or teleoperated laparoscopic instruments with visual, force sensor, or sensorless force estimation feedback. In a peg transfer experiment with 10 users, the contribution of sensorless haptic feedback with/without learning-based dynamic compensation was assessed using NASA TLX surveys, measured free motion speeds and forces, environment interaction forces as well as experiment completion times. RESULTS: The first study showed a 30% increase in accuracy in detecting tumors with sensorless haptic feedback over visual feedback with only a 5-10% drop in accuracy when compared with sensor feedback or direct instrument contact. The second study showed that sensorless feedback can help reduce interaction forces due to incidental contacts by about 3 times compared with unilateral teleoperation. The cost is an increase in free motion forces and physical effort. We show that it is possible to improve this with dynamic compensation. CONCLUSION: We demonstrate the benefits of sensorless haptic feedback in teleoperated surgery systems, especially with dynamic compensation, and that it can improve surgical performance without hardware modifications.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/instrumentación , Fantasmas de Imagen , Diseño de Equipo , Telemedicina/instrumentación , Palpación/métodos , Palpación/instrumentación , Interfaz Usuario-Computador , Retroalimentación , Robótica/instrumentación , Robótica/métodos , Laparoscopía/métodos , Laparoscopía/instrumentación
3.
IEEE Trans Biomed Eng ; 71(6): 1958-1968, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38261510

RESUMEN

OBJECTIVE: Robot-assisted minimally invasive surgery remains limited by the absence of haptic feedback, which surgeons routinely rely on to assess tissue stiffness. This limitation hinders surgeons' ability to identify and treat abnormal tissues, such as tumors, during robotic surgery. METHODS: To address this challenge, we developed a robotic tissue palpation device capable of rapidly and non-invasively quantifying the stiffness of soft tissues, allowing surgeons to make objective and data-driven decisions during minimally invasive procedures. We evaluated the effectiveness of our device by measuring the stiffness of phantoms as well as lung, heart, liver, and skin tissues obtained from both rats and swine. RESULTS: Results demonstrated that our device can accurately determine tissue stiffness and identify tumor mimics. Specifically, in swine lung, we determined elastic modulus (E) values of 9.1 ± 2.3, 16.8 ± 1.8, and 26.0 ± 3.6 kPa under different internal pressure of the lungs (PIP) of 2, 25, and 45 cmH2O, respectively. Using our device, we successfully located a 2-cm tumor mimic embedded at a depth of 5 mm in the lung subpleural region. Additionally, we measured E values of 33.0 ± 5.4, 19.2 ± 2.2, 33.5 ± 8.2, and 22.6 ± 6.0 kPa for swine heart, liver, abdominal skin, and muscle, respectively, which closely matched existing literature data. CONCLUSION/SIGNIFICANCE: Results suggest that our robotic palpation device can be utilized during surgery, either as a stand-alone or additional tool integrated into existing robotic surgical systems, to enhance treatment outcomes by enabling accurate intraoperative identification of abnormal tissue.


Asunto(s)
Diseño de Equipo , Procedimientos Quirúrgicos Mínimamente Invasivos , Palpación , Procedimientos Quirúrgicos Robotizados , Animales , Porcinos , Procedimientos Quirúrgicos Robotizados/instrumentación , Procedimientos Quirúrgicos Robotizados/métodos , Ratas , Palpación/instrumentación , Palpación/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Fantasmas de Imagen , Pulmón/cirugía , Pulmón/fisiología , Módulo de Elasticidad , Hígado/cirugía , Hígado/diagnóstico por imagen
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 1330-1335, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34891530

RESUMEN

Palpation is a clinical diagnosis method utilized by physicians to acquire valuable information about the pathological condition of an organ using the sense of touch. This method, however, is subjective. The accuracy depends on the physician's experience and skill. Therefore, to make palpation objective and minimize variability in prostate cancer diagnosis among physicians, an automated palpation system is required. This paper describes the design and experimental evaluation of a 2 Degrees of Freedom (2DoF) tendon driven robotic palpation probe. The probe's palpation motion is controlled by actuating driving tendons using a cable-differential pulley transmission system and a return spring. A kinematic model of the robotic probe was derived. Furthermore, a tendon path length model was geometrically determined, and an optimization method for guide arc center placement to minimize change in tendon length was presented. Preliminary experimental and theoretical results were compared to determine the positioning accuracy. The difference between theoretical pitch angles [0°,80°] and measured values for the yaw angle range of [0°, 40°] was found to be in the range of 0.03° ~ 5.06°.Clinical Relevance- Diagnosis based on manual palpation is often subjective and palpation sensitivity depends on the physician's level of experience and skill. Therefore, an objective method for acquiring tactile information is relevant. Robotic palpation system provides objective and quantitative information for better understanding of the pathological and physiological changes in the tissue using mechanical properties as biomarkers.


Asunto(s)
Palpación/instrumentación , Próstata , Robótica , Humanos , Masculino , Tendones
5.
Phys Ther ; 100(3): 429-437, 2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-32043149

RESUMEN

BACKGROUND: Decreased pectoralis minor muscle length is common after primary breast cancer treatment and can result in an abnormal position of the scapula. This position can contribute to shoulder pain and pathomechanics and can lead to problems such as impingement syndrome, rotator cuff tears, and frozen shoulder. Currently, there are limited reliable methods for measuring pectoralis minor length. OBJECTIVE: The objective of this study was to examine the reliability and validity of measuring pectoralis minor length in women diagnosed with breast cancer. DESIGN: This was a cross-sectional reliability and validity study. METHODS: Bilateral pectoralis minor length (in centimeters) was assessed using a palpation meter in women (N = 29) diagnosed with breast cancer by 2 licensed physical therapists who were masked to the measures. Bilateral pectoralis minor length was also measured using a motion capture system to assess validity. RESULTS: Intratester reliability (intraclass correlation coefficient, ICC [3,k] = 0.971; 95% confidence interval [CI] = 0.939-0.986; standard error of measurement [SEM] = 0.16 cm) and intertester reliability (ICC[3,k] = 0.915; 95% CI = 0.81-0.962; SEM = 0.31 cm) were excellent for the palpation meter on the affected side and the unaffected side (intratester reliability: ICC[3,k] = 0.951; 95% CI = 0.897-0.977; SEM = 0.19 cm; intertester reliability: ICC[3,k] = 0.945; 95% CI = 0.877-0.975; SEM = 0.22 cm). Significant correlations were found between the motion capture system and the palpation meter on the affected side (r = 0.87) and the unaffected side (r = 0.81). Bland-Altman plots between the palpation meter and the motion capture system demonstrated that all the measures fell within the limits of agreement. LIMITATIONS: This study encountered possible errors with the accuracy of the motion capture system tracking because of the proximity of the markers and inherent volumetric restrictions. CONCLUSIONS: The palpation meter is a reliable, valid, easily administered, and cost-effective tool for assessing pectoralis minor length in women with breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Palpación/instrumentación , Músculos Pectorales/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/terapia , Intervalos de Confianza , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Movimientos de los Órganos , Tamaño de los Órganos , Palpación/métodos , Reproducibilidad de los Resultados , Escápula/patología
6.
Sensors (Basel) ; 19(3)2019 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-30717482

RESUMEN

Advancements in the study of the human sense of touch are fueling the field of haptics. This is paving the way for augmenting sensory perception during object palpation in tele-surgery and reproducing the sensed information through tactile feedback. Here, we present a novel tele-palpation apparatus that enables the user to detect nodules with various distinct stiffness buried in an ad-hoc polymeric phantom. The contact force measured by the platform was encoded using a neuromorphic model and reproduced on the index fingertip of a remote user through a haptic glove embedding a piezoelectric disk. We assessed the effectiveness of this feedback in allowing nodule identification under two experimental conditions of real-time telepresence: In Line of Sight (ILS), where the platform was placed in the visible range of a user; and the more demanding Not In Line of Sight (NILS), with the platform and the user being 50 km apart. We found that the entailed percentage of identification was higher for stiffer inclusions with respect to the softer ones (average of 74% within the duration of the task), in both telepresence conditions evaluated. These promising results call for further exploration of tactile augmentation technology for telepresence in medical interventions.


Asunto(s)
Retroalimentación Sensorial/fisiología , Palpación/instrumentación , Dedos/fisiología , Gestos , Guantes Protectores , Humanos , Fantasmas de Imagen , Tacto/fisiología , Interfaz Usuario-Computador
7.
Skin Res Technol ; 25(4): 469-481, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30624813

RESUMEN

BACKGROUND: Haptic skin palpation with three-dimensional skin surface reconstruction from in vivo skin images in order to acquire both tactile and visual information has been receiving much attention. However, the depth estimation of skin surface, using a light field camera that creates multiple images with a micro-lens array, is a difficult problem due to low-resolution images resulting in erroneous disparity matching. METHODS: Multiple low-resolution images decoded from a light field camera have limitations to accurate 3D surface reconstruction needed for haptic palpation. To overcome this, a deep learning method, Generative Adversarial Networks, was employed to generate super-resolved skin images that preserve surface detail without blurring, and then, accurate skin depth was estimated by taking multiple subsequent steps including lens distortion correction, sub-pixel shifted image generation using phase shift theorem, cost-volume building, multi-label optimization, and hole filling and refinement, which is a new approach for 3D skin surface reconstruction. RESULTS: Experimental results of the deep-learning-based super-resolution method demonstrated that the textural detail (wrinkles) of super-resolved skin images is well preserved, unlike other super-resolution methods. In addition, the depth maps computed with our proposed algorithm verify that our method can produce more accurate and robust results compared to other state-of-the-art depth map computation methods. CONCLUSION: Herein, we first proposed depth map estimation of skin surfaces using a light field camera and subsequently tested it with several skin images. The experimental results established the superiority of the proposed scheme.


Asunto(s)
Palpación/instrumentación , Piel/anatomía & histología , Tacto/fisiología , Algoritmos , Estudios de Evaluación como Asunto , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Palpación/métodos , Piel/diagnóstico por imagen , Estadística como Asunto/métodos
8.
Skin Res Technol ; 25(3): 305-317, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30604497

RESUMEN

BACKGROUND/PURPOSE: Many studies have revealed the importance of palpation for dermatologists; however, palpation is not always possible due to the risk of secondary infections or the risk of damaging the affected area. Thus, haptic rendering for indirect palpation using in-vivo skin images, which will enable to examine a real three-dimensional (3D) skin sample by virtual touch without directly palpating the infected skin area, could be a useful technology in dermatology. METHODS: We propose a new method of accurate 3D skin surface reconstruction using simple gradients from a single skin image for accurate 3D roughness rendering with a haptic device. Our approach takes advantage of bilateral filtering to preserve skin roughness and image gradients in order to generate a 3D skin surface (polygonal meshes) while preserving skin wrinkles and rough surface textures. RESULTS: Our method was evaluated using two experiments. The accuracy was tested with six 3D ground-truth surfaces and four clinical skin images (acne, miliaria, sweet syndrome, and herpes simplex). For objective evaluation, a well-known 3D roughness estimation method and the Hausdorff distance were adopted to compute errors. All results showed that the accuracy of our method is superior to that of the two existing methods. CONCLUSION: Haptic roughness rendering for skin palpation examination requires efficient and accurate 3D surface reconstruction. In this study, we developed a new method that can be used to reconstruct a 3D skin surface accurately while preserving roughness through the use of a single skin image.


Asunto(s)
Imagenología Tridimensional/métodos , Palpación/instrumentación , Piel/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Palpación/métodos , Piel/patología , Propiedades de Superficie
9.
Surg Endosc ; 33(4): 1252-1259, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30187198

RESUMEN

BACKGROUND: The loss of tactile feedback in minimally invasive robotic surgery remains a major challenge to the expanding field. With visual cue compensation alone, tissue characterization via palpation proves to be immensely difficult. This work evaluates a bimodal vibrotactile system as a means of conveying applied forces to simulate haptic feedback in two sets of studies simulating an artificial palpation task using the da Vinci surgical robot. METHODS: Subjects in the first study were tasked with localizing an embedded vessel in a soft tissue phantom using a single-sensor unit. In the second study, subjects localized tumor-like structures using a three-sensor array. In both sets of studies, subjects completed the task under three trial conditions: no feedback, normal force tactile feedback, and hybrid vibrotactile feedback. Recordings of correct localization, incorrect localization, and time-to-completion were used to evaluate performance outcomes. RESULTS: With the addition of vibrotactile and pneumatic feedback, significant improvements in the percentage of correct localization attempts were detected (p = 0.0001 and p = 0.0459, respectively) during the first experiment with phantom vessels. Similarly, significant improvements in correct localization were found with the addition of vibrotactile (p = 2.57E-5) and pneumatic significance (p = 8.54E-5) were observed in the second experiment involving tumor phantoms. CONCLUSIONS: This work demonstrates not only the superior benefits of a multi-modal feedback over traditional single-modality feedback, but also the effectiveness of vibration in providing haptic feedback to artificial palpation systems.


Asunto(s)
Retroalimentación Sensorial , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Palpación/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Vasos Sanguíneos , Diseño de Equipo , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Modelos Anatómicos , Neoplasias , Palpación/instrumentación , Procedimientos Quirúrgicos Robotizados/instrumentación , Tacto , Vibración
10.
Comput Biol Med ; 96: 166-177, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29597142

RESUMEN

The currently available prostate palpation simulators are based on either a physical mock-up or pure virtual simulation. Both cases have their inherent limitations. The former lacks flexibility in presenting abnormalities and scenarios because of the static nature of the mock-up and has usability issues because the prostate model must be replaced in different scenarios. The latter has realism issues, particularly in haptic feedback, because of the very limited performance of haptic hardware and inaccurate haptic simulation. This paper presents a highly flexible and programmable simulator with high haptic fidelity. Our new approach is based on a pneumatic-driven, property-changing, silicone prostate mock-up that can be embedded in a human torso mannequin. The mock-up has seven pneumatically controlled, multi-layered bladder cells to mimic the stiffness, size, and location changes of nodules in the prostate. The size is controlled by inflating the bladder with positive pressure in the chamber, and a hard nodule can be generated using the particle jamming technique; the fine sand in the bladder becomes stiff when it is vacuumed. The programmable valves and system identification process enable us to precisely control the size and stiffness, which results in a simulator that can realistically generate many different diseases without replacing anything. The three most common abnormalities in a prostate are selected for demonstration, and multiple progressive stages of each abnormality are carefully designed based on medical data. A human perception experiment is performed by actual medical professionals and confirms that our simulator exhibits higher realism and usability than do the conventional simulators.


Asunto(s)
Modelos Biológicos , Palpación/instrumentación , Palpación/métodos , Próstata/fisiología , Vejiga Urinaria/fisiología , Adulto , Ingeniería Biomédica/instrumentación , Instrucción por Computador/instrumentación , Diseño de Equipo , Femenino , Humanos , Masculino
11.
Skin Res Technol ; 24(2): 203-212, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29067717

RESUMEN

BACKGROUND/PURPOSE: Very little is known about the methods of integrating palpation techniques to existing mobile teleskin imaging that delivers low quality tactile information (roughness) for telepalpation. However, no study has been reported yet regarding telehaptic palpation using mobile phone images for teledermatology or teleconsultations of skincare. METHODS: This study is therefore aimed at introducing a new algorithm accurately reconstructing a haptic augmented skin surface for telehaptic palpation using a low-cost clip-on microscope simply attached to a mobile phone. Multiple algorithms such as gradient-based image enhancement, roughness-adaptive tactile mask generation, roughness-enhanced 3D tactile map building, and visual and haptic rendering with a three-degrees-of-freedom (DOF) haptic device were developed and integrated as one system. RESULTS: Evaluation experiments have been conducted to test the performance of 3D roughness reconstruction with/without the tactile mask. The results confirm that reconstructed haptic roughness with the tactile mask is superior to the reconstructed haptic roughness without the tactile mask. Additional experiments demonstrate that the proposed algorithm is robust against varying lighting conditions and blurring. In last, a user study has been designed to see the effect of the haptic modality to the existing visual only interface and the results attest that the haptic skin palpation can significantly improve the skin exam performance. CONCLUSION: Mobile image-based telehaptic palpation technology was proposed, and an initial version was developed. The developed technology was tested with several skin images and the experimental results showed the superiority of the proposed scheme in terms of the performance of haptic augmentation of real skin images.


Asunto(s)
Palpación/métodos , Consulta Remota/métodos , Piel/anatomía & histología , Tacto , Algoritmos , Teléfono Celular , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Palpación/instrumentación
12.
Med Biol Eng Comput ; 56(2): 297-305, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28714049

RESUMEN

Hardness, dimensions, and location of biological tissues are important parameters for electronic palpation protocols with standardized performance. This study presents a novel fluid-type tactile sensor able to measure size and depth of heterogeneous substances in elastic bodies. The new sensor is very simple and can be easily fabricated. It consists of an image sensor, LED lights, and a touchpad filled with translucent water. The intensity field of the light traveling in the touchpad is analyzed to estimate the touchpad shape which conforms to the shape of an object in contact. The use of the new sensor for measuring size and depth of heterogeneous substances inside elastic bodies as well as hardness of elastic bodies is illustrated. Results obtained for breast cancer dummies demonstrate the effectiveness of the proposed approach.


Asunto(s)
Palpación/instrumentación , Tacto , Neoplasias de la Mama/diagnóstico , Diseño de Equipo , Femenino , Humanos , Modelos Teóricos , Visión Ocular
13.
Anesth Analg ; 126(1): 120-126, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29135593

RESUMEN

BACKGROUND: Radial arterial cannulation is most commonly done using palpation, but the use of ultrasound has increased the cannulation success rate. This improvement, albeit significant, has not led to a very high success rate especially in trainees. A modified ultrasound technique for vascular cannulation (dynamic needle tip positioning) has been described for peripheral venous cannulation. We therefore assessed the success rate of this technique compared to the palpation technique for radial artery cannulation in adult surgical patients. METHODS: We enrolled patients who were having nonemergent operations that required a radial arterial catheter for intraoperative monitoring. Patients were randomized to either palpation or dynamic needle tip positioning technique. Arterial cannulation was performed by anesthesia residents or faculty members. The primary end point was successful cannulation on the first pass. Secondary end points were overall 5-minute success rate and number of attempts within 5 minutes. RESULTS: Two hundred sixty patients were evaluated. The first-pass success rate was 83% in the dynamic needle tip positioning technique group (n = 132) and 48% in the palpation group (n = 128; P < .001); relative risk was 2.5; 95% confidence interval, 1.7-3.6. The overall 5-minute success rate was 89% in the dynamic needle tip positioning technique group compared to 65% in the palpation group (P < .001), relative risk was 2.4; 95% confidence interval, 1.2-1.6. The number of skin puncture attempts was significantly more in the palpation group (P < .001). The median cannulation times and interquartile ranges were 81.5 (61-122) seconds in the dynamic needle tip positioning and 76 (48-175) seconds (P = .7) in the palpation group. CONCLUSIONS: The use of the ultrasound-guided dynamic needle tip positioning technique increased the first and overall success rates compared to palpation in anesthesia residents and faculty members.


Asunto(s)
Cateterismo Periférico/métodos , Agujas , Palpación/métodos , Arteria Radial/diagnóstico por imagen , Ultrasonografía Intervencional/métodos , Adulto , Anciano , Cateterismo Periférico/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Palpación/instrumentación , Estudios Prospectivos , Arteria Radial/cirugía , Ultrasonografía Intervencional/instrumentación
14.
Proc Inst Mech Eng H ; 231(12): 1101-1115, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28965477

RESUMEN

The objective is to establish the feasibility of using dynamic instrumented palpation, a novel technique of low-frequency mechanical testing, applied here to diagnose soft tissue condition. The technique is applied, in vitro, to samples of excised prostate gland affected by benign prostate hyperplasia and/or prostate cancer. Particular attention is paid to the relationship between the histological structure of the tissue and the dynamic mechanical properties in an attempt to separate patient-specific aspects from histopathological condition (i.e. prostate cancer or benign prostate hyperplasia). The technique is of clinical interest because it is potentially deployable in vivo. Prostate samples were obtained from a total of 36 patients who had undergone transurethral resection of the prostate to relieve prostatic obstruction and 4 patients who had undergone radical cystoprostatectomy for bladder cancer. Specimens (chips) recovered from transurethral resection of the prostate were of nominal size 5 mm × 8 mm and thicknesses between 2 and 4 mm, whereas those from the cystoprostatectomy were in the form of transverse slices of thickness approximately 6 mm. Specimens were mechanically tested by a controlled strain cyclic compression technique, and the resulting dynamic mechanical properties expressed as the amplitude ratio and phase difference between the cyclic stress and cyclic strain. After mechanical testing, the percentage areas of glandular and smooth muscle were measured at each probe point. Good contrast between the dynamic modulus of chips from benign prostate hyperplasia and prostate cancer patients was demonstrated, and absolute values similar to those published by other authors are reported. For the slices, modulus values were considerably higher than for chips, and good in-patient mechanical contrast was revealed for predominantly nodular and predominantly stromal areas. Extending this classification between patients required pattern recognition techniques. Overall, the study has demonstrated that dynamic mechanical properties can potentially be used for diagnosis of prostate condition using in vivo measurements.


Asunto(s)
Palpación/instrumentación , Próstata/patología , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patología , Fenómenos Biomecánicos , Humanos , Masculino
15.
Proc Inst Mech Eng H ; 231(12): 1081-1100, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28965486

RESUMEN

An instrumented palpation sensor, designed for measuring the dynamic modulus of tissue in vivo, has been developed and trialled on ex vivo whole prostate glands. The sensor consists of a flexible membrane sensor/actuator with an embedded strain gauge and is actuated using a dynamically varying airflow at frequencies of 1 and 5 Hz. The device was calibrated using an indentation stiffness measurement rig and gelatine samples with a range of static modulus similar to that reported in the literature for prostate tissue. The glands were removed from patients with diagnosed prostate cancer scheduled for radical prostatectomy, and the stiffness was measured within 30 min of surgical removal. Each prostate was later examined histologically in a column immediately below each indentation point and graded into one of the four groups; normal, benign prostatic hyperplasia, cancerous and mixed cancer and benign prostatic hyperplasia. In total, 11 prostates were assessed using multiple point probing, and the complex modulus at 1 and 5 Hz was calculated on a point-by-point basis. The device yielded values of quasi-static modulus of 15 ± 0.5 kPa and dynamic modulus of 20 ± 0.5 kPa for whole prostates, and a sensitivity of up to 80% with slightly lower specificity was achieved on diagnosis of prostate cancer using a combination of mechanical measures. This assessment did not take into account some obvious factors such as edge effects, overlap and clinical significance of the cancer, all of which would improve performance. The device, as currently configured, is immediately deployable in vivo. A number of improvements are also identified which could improve the sensitivity and specificity in future embodiments of the probe.


Asunto(s)
Fenómenos Mecánicos , Palpación/instrumentación , Próstata/patología , Fenómenos Biomecánicos , Humanos , Masculino , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/patología
16.
J Am Podiatr Med Assoc ; 107(2): 112-118, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28394688

RESUMEN

BACKGROUND: The aim of this work is to introduce a useful method for the clinical diagnosis of leg-length inequality: distance between the malleoli and the ground (DMG). METHODS: A transversal observational study was performed on 17 patients with leg-length discrepancy. Leg-length inequality was determined with different clinical methods: with a tape measure in a supine position from the anterior superior iliac spine (ASIS) to the internal and external malleoli, as the difference between the iliac crests when standing (pelvimeter), and as asymmetry between ASISs (PALpation Meter [PALM]; A&D Medical Products Healthcare, San Jose, California). The Foot Posture Index (FPI) and the navicular drop test were also used. The DMG with Perthes rule (perpendicular to the foot when standing), the distance between the internal malleolus and the ground (DIMG), and the distance between the external malleolus and the ground were designed by the authors. RESULTS: The DIMG is directly related to the traditional ASIS-external malleolus measurement (P = .003), the FPI (P = .010), and the navicular drop test (P < .001). There are statistically significant differences between measurement of leg-length inequality with a tape measure, in supine decubitus, from the ASIS to the internal malleolus, and from the ASIS to the external malleolus. CONCLUSIONS: This new method (the DMG) is useful for diagnosing leg-length discrepancy and is related to the ASIS-external malleolus measurement. The DIMG is significantly inversely proportional to the degree of pronation according to the FPI. Conversely, determination of leg-length discrepancy with a tape measure from the ASIS to the malleoli cannot be performed interchangeably at the level of the internal or external malleolus.


Asunto(s)
Diferencia de Longitud de las Piernas/diagnóstico , Palpación/instrumentación , Examen Físico/métodos , Radiografía/métodos , Huesos Tarsianos/anatomía & histología , Adolescente , Adulto , Fracturas de Tobillo , Estudios de Cohortes , Intervalos de Confianza , Femenino , Humanos , Diferencia de Longitud de las Piernas/diagnóstico por imagen , Masculino , Palpación/métodos , Posicionamiento del Paciente/métodos , Podiatría/métodos , Estadísticas no Paramétricas , Posición Supina , Huesos Tarsianos/diagnóstico por imagen , Adulto Joven
17.
IEEE Trans Neural Syst Rehabil Eng ; 25(5): 426-435, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27244744

RESUMEN

Biomechanical tissue properties have been hypothesized to play a critical role in the quantification of prosthetic socket production for individuals with limb amputation. In this investigation, a novel indenter platform is presented and its performance evaluated for the purposes of residual-limb tissue characterization. The indenter comprised 14 position- and force-controllable actuators that circumferentially surround a biological residuum to form an actuator ring. Each indenter actuator was individually controllable in position ( [Formula: see text] accuracy) and force (330 mN accuracy) at a PC controller feedback rate of 500 Hz, allowing for a range of measurement across a residual stump. Data were collected from 162 sensors over an EtherCAT fieldbus to characterize the mechanical hyperviscoelastic tissue response of two transtibial residual-limbs from a study participant with bilateral amputations. At five distinct anatomical locations across the residual-limb, force versus deflection data-including hyperviscoelastic tissue properties-are presented, demonstrating the accuracy and versatility of the multi-indenter platform for residual-limb tissue characterization.


Asunto(s)
Muñones de Amputación/fisiopatología , Módulo de Elasticidad , Pruebas de Dureza/instrumentación , Palpación/instrumentación , Estimulación Física/instrumentación , Viscosidad , Diseño de Equipo , Análisis de Falla de Equipo , Pruebas de Dureza/métodos , Humanos , Articulación de la Rodilla/fisiopatología , Sistemas Microelectromecánicos/instrumentación , Sistemas Microelectromecánicos/métodos , Estimulación Física/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
BMC Med Educ ; 16(1): 274, 2016 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-27756288

RESUMEN

BACKGROUND: Mobile learning (m-learning) has becoming very popular in education due to the rapidly advancing technology in our society. The potentials of the mobile applications should be used to enhance the education process. Few mobile applications have been designed to complement the study of physical therapy skills for physiotherapy students. The aim of this study was to investigate whether a mobile application, as a supplement to traditional learning, is useful for physiotherapy students in the acquisition of palpation and ultrasound skills in the shoulder area. METHODS: Forty-nine students participated in this single-blinded, randomized controlled study. They were randomly distributed into two groups: experimental, with free access to the mobile application; and control, with access to traditional learning materials on the topic. Objective structured clinical evaluation (OSCE) and multiple-choice questionnaire (MCQ) were used to assess the educational intervention. Then, we also assessed the time taken to get a reliable ultrasound image and to localize a specific shoulder structure by palpation. RESULTS: There was no significant intergroup difference in the acquisition of theoretical knowledge (p = .089). Scores were significantly higher in the experimental group than in the control group for the majority items in the ultrasound assessment; positioning of patient (p < .001), positioning of ultrasound probe (p = 0.007), handling of ultrasound probe (p = .013) and global OSCE (p < .001) and skills in palpation of the shoulder; position of patient (p = .009), direction of palpation contact (p = .021) and global OSCE (p = .034). There were no significant differences in the time required to perform the examination between groups in ultrasound (p = .944) and palpation (p = .393). The results from the post-program survey assessing the global satisfaction with the mobile application were high (8.200 ± .767), on an 11 numeric point rating scale. CONCLUSION: These results suggest the effectiveness of an m-learning program as a complement to traditional education for developing skills in ultrasound and palpation of the shoulder region in undergraduate physiotherapy students.


Asunto(s)
Competencia Clínica/normas , Educación de Pregrado en Medicina , Aplicaciones Móviles , Músculo Esquelético/diagnóstico por imagen , Examen Físico , Modalidades de Fisioterapia/instrumentación , Especialidad de Fisioterapia/educación , Actitud del Personal de Salud , Instrucción por Computador , Curriculum , Educación de Pregrado en Medicina/métodos , Evaluación Educacional , Humanos , Palpación/instrumentación , España , Ultrasonografía/instrumentación
19.
Stud Health Technol Inform ; 220: 77-83, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27046557

RESUMEN

High fidelity surgical simulations must rely upon accurate soft tissue models to ensure realism of the simulations. Simulating multi-layer tissue becomes increasingly complex due to the specific mechanical properties of each individual layer. We have developed a Soft Tissue Elastography Robotic Arm (STiERA) system capable of identifying layer specific properties of multi-layer constructs while maintaining the integrity of each layer. The system was validated using tissue mimicking agar gel phantoms and showed great promise by identifying the layer specific properties with accuracy of greater than 80% when compared to known ground truth values from a commercial material testing system.


Asunto(s)
Tejido Conectivo/diagnóstico por imagen , Tejido Conectivo/fisiología , Diagnóstico por Imagen de Elasticidad/instrumentación , Palpación/instrumentación , Estimulación Física/instrumentación , Procedimientos Quirúrgicos Robotizados/instrumentación , Tejido Conectivo/cirugía , Módulo de Elasticidad/fisiología , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Stud Health Technol Inform ; 220: 193-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27046577

RESUMEN

Sensor enabled simulators may help in training and assessing clinical skill. Their are imitations on the locations current sensors can be placed without interfering with the clinical examination. In this study novel fabric force sensors were developed and tested. These sensors are soft and flexible and undetectable when placed in different locations in the simulator. Five sensors were added to our current sensor enabled breast simulator. Eight participants performed the clinical breast examination on the simulator and documented their findings. There was a significant relationship for both clinical breast examination time (r(6) = 0.99, p < 0.001) and average force (r(6) = 0.92, p < 0.005) between our current sensors and the new fabric sensors. In addition the senors were not noticed by the participants. These new sensors provide new methods to measure and assess clinical skill and performance.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Enseñanza Mediante Simulación de Alta Fidelidad/métodos , Palpación/instrumentación , Tacto , Transductores de Presión , Competencia Clínica , Vestuario , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Palpación/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estrés Mecánico
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