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Ultrasound-guided needle interventions play a pivotal role in the diagnosis and treatment processes in clinical practice. However, existing echogenic needles face challenges in achieving a balance between effectiveness, ease of manufacturing, and inexpensiveness. In this study, we developed an echogenic needle that encompassed the aforementioned advantages through the use of the electrolysis technology. The overall contour of the needle after electrolysis was observed using bright-field microscopy, while scanning electron microscopy (SEM) was employed to examine the micro-variations on the needle's surface. Subsequently, we validated the enhanced visualization effects in vitro (pork) and in vivo (anesthetized rabbit's thigh) puncture phantoms. To ensure the safety of the needles after the puncture procedure, we conducted Vickers hardness tests, SEM detection, bright-field microscopy, and DAPI staining. The results demonstrated that the surface roughness of the needle increased with the duration of electrolysis. Taking into account the comprehensive safety tests, the needle, subjected to 40 s of electrolysis, demonstrated a safe and effective enhancement of ultrasound visualization.

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Background: Obtaining an adequate image of the needle by ultrasound reduces complications resulting from punctures, increasing patient safety and reducing hospitalization costs. Objectives: To verify human perception in relation to number of pixels, while also identifying the best puncture angle and which needle should be used, and to evaluate whether there is a difference if needle visualization software is used. Methods: 20 images were analyzed by 103 students who classified them as being sufficient or insufficient and were compared with the quality observed using photoshop. We evaluated whether there were differences between puncture angles of less than 45º and more than 45º, between IV catheter and introducer needles, and between images obtained with and without visualization software. Results: There was a higher percentage of sufficient ratings for images those that had more than 60 pixels and when the puncture angle was less than 45º, with significant associations between students' evaluations and each of these groups (p < 0.001). The percentages of images classified as sufficient were higher for images in which a IV catheter was used and also higher for those using the needle visualization software, with significant associations between the results for students' classifications and each of these groups (p < 0.001). Conclusions: The human eye classifies an image as sufficient according to higher numbers of pixels. Images of punctures at angles smaller than 45º in relation to the surface, of punctures performed with a IV catheter, and when using specific visualization software are also better detected by the human eye.

Contexto: A obtenção de uma imagem adequada da agulha pelo ultrassom diminui complicações decorrentes de punções, trazendo segurança para os pacientes e diminuindo custos com hospitalização. Objetivos: Verificar a percepção do olho humano em relação aos pixels, identificar qual o melhor ângulo da punção e qual agulha deve ser utilizada e avaliar se há diferença com o uso de software de visualização de agulha. Métodos: Vinte imagens foram analisadas por 103 alunos, que as classificaram como sendo suficientes ou insuficientes, e comparadas com a qualidade observada pelo photoshop. Avaliou-se se havia diferença entre punções com menos de 45º e mais de 45º, entre cateter EV e agulha introdutora e entre imagens obtidas com e sem software de visualização. Resultados: Houve um percentual mais elevado de imagens suficientes entre aquelas que tinham mais de 60 pixels e quando o ângulo era menor que 45º, com associação significativa entre a classificação das avaliações pelos alunos e cada um desses grupos (p < 0,001). O percentual de imagens suficientes foi maior nas imagens realizadas com cateter EV e naquelas que utilizaram o software de visualização da agulha, ocorrendo associação significativa entre os resultados da classificação pelos alunos e cada um desses grupos (p < 0,001). Conclusões: O olho humano classifica a imagem como sendo suficiente de acordo com a maior quantidade de pixels. Imagens puncionadas com ângulos menores que 45º em relação à superfície, realizadas com cateter EV e utilizando software específico de visualização também são mais bem detectadas pelo olho humano.

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Objective To investigate the influencing factors and establish a model predicting the performance of needle visualization in fine-needle aspiration (FNA) of thyroid nodules. Methods This study prospectively included 175 patients who underwent FNA of thyroid nodules in the Department of Ultrasound in China-Japan Friendship Hospital and compared the display of the needle tips in the examination of 199 thyroid nodules before and after the application of needle visualization.We recorded the location,the positional relationship with thyroid capsule,ultrasonic characteristics,and the distribution of the soft tissue strip structure at the puncture site of the nodules with unclear needle tips display before using needle visualization.Furthermore,according to the thyroid imaging reporting and data system proposed by the American College of Radiology,we graded the risk of the nodules.Lasso-Logistic regression was employed to screen out the factors influencing the performance of needle visualization and establish a nomogram for prediction. Results The needle tips were not clearly displayed in the examination of 135 (67.8%) and 53 (26.6%) nodules before and after the application of needle visualization,respectively,which showed a significant difference (P<0.001).Based on the positional relationship between the nodule and capsule,anteroposterior/transverse diameter (A/T) ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site,a nomogram was established to predict the probability of unclear display of the needle tips after application of needle visualization.The C-index of the prediction model was 0.75 (95%CI=0.67-0.84) and the area under the receiver operating characteristic curve was 0.72.The calibration curve confirmed the appreciable reliability of the prediction model,with the C-index of 0.70 in internal validation. Conclusions Needle visualization can improve the display of the needle tip in ultrasound-guided FNA of thyroid nodules.The nomogram established based on ultrasound features such as the positional relationship between the nodule and capsule,A/T ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site can predict whether needle visualization is suitable for the examination of nodules.

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PURPOSE: High-dose-rate (HDR) interstitial brachytherapy (BT) is a common treatment technique for localized intermediate to high-risk prostate cancer. Transrectal ultrasound (US) imaging is typically used for guiding needle insertion, including localization of the needle tip which is critical for treatment planning. However, image artifacts can limit needle tip visibility in standard brightness (B)-mode US, potentially leading to dose delivery that deviates from the planned dose. To improve intraoperative tip visualization in visually obstructed needles, we propose a power Doppler (PD) US method which utilizes a novel wireless mechanical oscillator, validated in phantom experiments and clinical HDR-BT cases as part of a feasibility clinical trial. METHODS: Our wireless oscillator contains a DC motor housed in a 3D printed case and is powered by rechargeable battery allowing the device to be operated by one person with no additional equipment required in the operating room. The oscillator end-piece features a cylindrical shape designed for BT applications to fit on top of the commonly used cylindrical needle mandrins. Phantom validation was completed using tissue-equivalent agar phantoms with the clinical US system and both plastic and metal needles. Our PD method was tested using a needle implant pattern matching a standard HDR-BT procedure as well as an implant pattern designed to maximize needle shadowing artifacts. Needle tip localization accuracy was assessed using the clinical method based on ideal reference needles as well as a comparison to computed tomography (CT) as a gold standard. Clinical validation was completed in five patients who underwent standard HDR-BT as part of a feasibility clinical trial. Needle tips positions were identified using B-mode US and PD US with perturbation from our wireless oscillator. RESULTS: Absolute mean ± standard deviation tip error for B-mode alone, PD alone, and B-mode combined with PD was respectively: 0.3 ± 0.3 mm, 0.6 ± 0.5 mm, and 0.4 ± 0.2 mm for the mock HDR-BT needle implant; 0.8 ± 1.7 mm, 0.4 ± 0.6 mm, and 0.3 ± 0.5 mm for the explicit shadowing implant with plastic needles; and 0.5 ± 0.2 mm, 0.5 ± 0.3 mm, and 0.6 ± 0.2 mm for the explicit shadowing implant with metal needles. The total mean absolute tip error for all five patients in the feasibility clinical trial was 0.9 ± 0.7 mm using B-mode US alone and 0.8 ± 0.5 mm when including PD US, with increased benefit observed for needles classified as visually obstructed. CONCLUSIONS: Our proposed PD needle tip localization method is easy to implement and requires no modifications or additions to the standard clinical equipment or workflow. We have demonstrated decreased tip localization error and variation for visually obstructed needles in both phantom and clinical cases, including providing the ability to visualize needles previously not visible using B-mode US alone. This method has the potential to improve needle visualization in challenging cases without burdening the clinical workflow, potentially improving treatment accuracy in HDR-BT and more broadly in any minimally invasive needle-based procedure.

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Objective To investigate the influencing factors and establish a model predicting the performance of needle visualization in fine-needle aspiration (FNA) of thyroid nodules. Methods This study prospectively included 175 patients who underwent FNA of thyroid nodules in the Department of Ultrasound in China-Japan Friendship Hospital and compared the display of the needle tips in the examination of 199 thyroid nodules before and after the application of needle visualization.We recorded the location,the positional relationship with thyroid capsule,ultrasonic characteristics,and the distribution of the soft tissue strip structure at the puncture site of the nodules with unclear needle tips display before using needle visualization.Furthermore,according to the thyroid imaging reporting and data system proposed by the American College of Radiology,we graded the risk of the nodules.Lasso-Logistic regression was employed to screen out the factors influencing the performance of needle visualization and establish a nomogram for prediction. Results The needle tips were not clearly displayed in the examination of 135 (67.8%) and 53 (26.6%) nodules before and after the application of needle visualization,respectively,which showed a significant difference (P<0.001).Based on the positional relationship between the nodule and capsule,anteroposterior/transverse diameter (A/T) ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site,a nomogram was established to predict the probability of unclear display of the needle tips after application of needle visualization.The C-index of the prediction model was 0.75 (95%CI=0.67-0.84) and the area under the receiver operating characteristic curve was 0.72.The calibration curve confirmed the appreciable reliability of the prediction model,with the C-index of 0.70 in internal validation. Conclusions Needle visualization can improve the display of the needle tip in ultrasound-guided FNA of thyroid nodules.The nomogram established based on ultrasound features such as the positional relationship between the nodule and capsule,A/T ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site can predict whether needle visualization is suitable for the examination of nodules.

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Abstract Background Obtaining an adequate image of the needle by ultrasound reduces complications resulting from punctures, increasing patient safety and reducing hospitalization costs. Objectives To verify human perception in relation to number of pixels, while also identifying the best puncture angle and which needle should be used, and to evaluate whether there is a difference if needle visualization software is used. Methods 20 images were analyzed by 103 students who classified them as being sufficient or insufficient and were compared with the quality observed using photoshop. We evaluated whether there were differences between puncture angles of less than 45º and more than 45º, between IV catheter and introducer needles, and between images obtained with and without visualization software. Results There was a higher percentage of sufficient ratings for images those that had more than 60 pixels and when the puncture angle was less than 45º, with significant associations between students' evaluations and each of these groups (p < 0.001). The percentages of images classified as sufficient were higher for images in which a IV catheter was used and also higher for those using the needle visualization software, with significant associations between the results for students' classifications and each of these groups (p < 0.001). Conclusions The human eye classifies an image as sufficient according to higher numbers of pixels. Images of punctures at angles smaller than 45º in relation to the surface, of punctures performed with a IV catheter, and when using specific visualization software are also better detected by the human eye.

Resumo Contexto A obtenção de uma imagem adequada da agulha pelo ultrassom diminui complicações decorrentes de punções, trazendo segurança para os pacientes e diminuindo custos com hospitalização. Objetivos Verificar a percepção do olho humano em relação aos pixels, identificar qual o melhor ângulo da punção e qual agulha deve ser utilizada e avaliar se há diferença com o uso de software de visualização de agulha. Métodos Vinte imagens foram analisadas por 103 alunos, que as classificaram como sendo suficientes ou insuficientes, e comparadas com a qualidade observada pelo photoshop. Avaliou-se se havia diferença entre punções com menos de 45º e mais de 45º, entre cateter EV e agulha introdutora e entre imagens obtidas com e sem software de visualização. Resultados Houve um percentual mais elevado de imagens suficientes entre aquelas que tinham mais de 60 pixels e quando o ângulo era menor que 45º, com associação significativa entre a classificação das avaliações pelos alunos e cada um desses grupos (p < 0,001). O percentual de imagens suficientes foi maior nas imagens realizadas com cateter EV e naquelas que utilizaram o software de visualização da agulha, ocorrendo associação significativa entre os resultados da classificação pelos alunos e cada um desses grupos (p < 0,001). Conclusões O olho humano classifica a imagem como sendo suficiente de acordo com a maior quantidade de pixels. Imagens puncionadas com ângulos menores que 45º em relação à superfície, realizadas com cateter EV e utilizando software específico de visualização também são mais bem detectadas pelo olho humano.

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Purpose: Ultrasound guidance during nerve blockade poses the challenge of maintaining in-plane alignment of the needle tip. The needle guidance device maintains needle alignment and assists with in-plane needle visualization. The purpose of this study is to evaluate the utility of this device by comparing procedure performance during brachial plexus blockade with the conventional approach. Methods: After the Institutional Review Board approval and obtaining informed consent, 70 patients receiving either interscalene or supraclavicular nerve blocks were randomly assigned into 2 groups, a conventional approach versus utilizing the needle guidance device. An independent observer recorded: total procedure time; needle insertion time; number of unplanned redirections; and number of reinsertions. Additionally, physician satisfaction and ease of needle visualization were assessed. Results: Data from seventy patients were analyzed. The median [25th percentile-75th percentile] time to complete the block by the device assisted needle guidance group was 3 (2-3.75) minutes and 4 (3-6) minutes in the conventional approach group (p < 0.001). Additionally, subgroup analyses were performed in the supraclavicular block and interscalene block. Supraclavicular blockade, needle insertion time (median [25th percentile-75th percentile] in seconds) (106 [92-162] vs 197 [140-278]), total procedure time (3 [2-3] vs 4.5 [4-6] in minutes) and unplanned needle redirections (2 [1-5] vs 5.5 [3-9]) were significantly lower in needle guidance group (p < 0.001). With interscalene blockade, needle insertion time (86 [76-146] vs 126 [94-295]) and unplanned needle redirections (2 [1-3] vs 4 [2-8.5]) were significantly lower with needle guidance (p < 0.001), but total procedure time was similar. All the physicians reported that they would use the needle guidance again, and 90% would prefer it for in-plane blocks. Conclusion: Performing regional blocks using the needle guidance device reduces needle insertion time and unplanned needle redirections in brachial plexus blockade. Moreover, physician satisfaction also improved compared to the use of the conventional technique.

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BACKGROUND: Cardiac tamponade occurs when fluid or blood, fills the pericardial space, and causes hemodynamic compromise due to compression of the heart. It is a potentially life-threatening condition, that requires rapid recognition and immediate treatment. Formerly, blind or surgical techniques were used, and it is associated with complications. Medical technology development has enabled us to perform the procedure safely, with the assistance of ultrasound devices. This article will highlight the novel use of an in-plane subcostal technique, as a safe option for pericardiocentesis in cardiac tamponade. CASE PRESENTATION: A 50-year-old man presented to the emergency department (ED) with shortness of breath and shock. He was intubated for respiratory distress. His bedside echocardiography showed cardiac tamponade. Ultrasound-guided pericardiocentesis was carried out using an in-plane technique, at the subcostal region, with a high-frequency linear ultrasound transducer. This particular method provided full visualization of needle trajectory throughout the procedure. It was successfully completed with no complications and patient's hemodynamic status improved post-procedure. He was successfully discharged on day 13. CONCLUSIONS: The in-plane subcostal pericardiocentesis is a safe, and simple approach that can be performed in the ED for patients with cardiac tamponade. We recommend this new in-plane method, with high-frequency linear transducer at the subcostal area as an alternative when cardiac window for other approaches cannot be visualized.

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PURPOSE: This scoping review covers needle visualization and localization techniques in ultrasound, where localization-based approaches mostly aim to compute the needle shaft (and tip) location while potentially enhancing its visibility too. METHODS: A literature review is conducted on the state-of-the-art techniques, which could be divided into five categories: (1) signal and image processing-based techniques to augment the needle, (2) modifications to the needle and insertion to help with needle-transducer alignment and visibility, (3) changes to ultrasound image formation, (4) motion-based analysis and (5) machine learning. RESULTS: Advantages, limitations and challenges of representative examples in each of the categories are discussed. Evaluation techniques performed in ex vivo, phantom and in vivo studies are discussed and summarized. CONCLUSION: Greatest limitation of the majority of the literature is that they rely on original visibility of the needle in the static image. Need for additional/improved apparatus is the greatest limitation toward clinical utility in practice. SIGNIFICANCE: Ultrasound-guided needle placement is performed in many clinical applications, including biopsies, treatment injections and anesthesia. Despite the wide range and long history of this technique, an ongoing challenge is needle visibility in ultrasound. A robust technique to enhance ultrasonic needle visibility, especially for steeply inserted hand-held needles, and while maintaining clinical utility requirements is needed.

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BACKGROUND: Ultrasound-guided paravertebral blocks during breast surgeries with in-plane needle approaches can be challenging due to difficult needle visualization. The purpose of this study was to assess the usefulness of using a needle guide while performing in-plane parasagittal approach paravertebral block for breast surgery. PATIENTS AND METHODS: Eighty patients, American Society of Anesthesiologists physical status I-III, aged 20-40 years with breast mass scheduled for simple mastectomy surgery, were involved in prospective, controlled, randomized study, and were randomly divided by closed envelope method into two groups: Group I (n = 40): Scheduled for ultrasound-guided paravertebral block or group II (n = 40): Scheduled for ultrasound-guided paravertebral block using the needle guide. Both techniques compared as regards: (i) Needle visibility and block performance time; (ii) number of needle passes; (iii) duration of the block; (iv) doctor and patient satisfaction; and (v) incidence of complications. RESULTS: Needle visibility score was better in group II (2.92 ± 0.26 vs. 1.9 ± 0.44, P < 0.0001). Block performance time was shorter in group II (90.92 ± 15 vs. 128.25 ± 16s, P < 0.0001). A number of needle passes were less in group II (1.27 ± 0.45 vs. 2.2 ± 0.68, P < 0.0001). Doctor and patient satisfaction were better in group II (P = 0.015). No differences were found regarding the duration of the block and incidence of complications between groups. CONCLUSION: A needle guide can help reduce the time needed to perform a parasagittal in-plane thoracic paravertebral block, with a significant reduction in the block performance time, the number of needle passes, better needle visibility and better doctor and patient's satisfaction. However, there was no significant difference regarding the duration of the block or incidence of complications.

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PURPOSE: A critical requirement of MR-guided interventions is the visualization of an instrument (e.g., catheter, needle) during the procedure. One approach is to fill the instrument with a contrast agent. Previously, the optimization of contrast agent visualization was performed only empirically. In the present study, an analytic optimization of contrast agent SNR efficiency was performed for a spoiled gradient echo pulse sequence. METHODS: Optimal flip angle, repetition time, echo time, and contrast agent concentration were derived analytically. The solution is valid for any contrast agent, provided the relationship between T1 , T2 , and doping concentration is known. RESULTS: Phantom experiments validated the analytic optimization for Gd- and MnCl2 -based contrast agents. Results showed excellent agreement between experimentally predicted and theoretically observed magnetization behavior. In vivo experiments demonstrated optimized contrast agent visualization in brain, heart, and prostate applications. The results demonstrated the large SNR that can be achieved with analytic optimization. As a practical guideline, an 11% dilution of 500 mMol/L Gd-DTPA solution, repetition time ≈ 4 ms, echo time ≈ 1 ms, and θ ≈ 65° was found to provide a large SNR. CONCLUSION: This study derived and validated a method for analytically optimizing contrast agent SNR efficiency. This information may be useful for visualizing instruments during MR-guided interventions.

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OBJECTIVE: To determine if the use of needle enhancing software facilitate injection technique in ultrasound-guided peripheral nerve blocks. STUDY DESIGN: Prospective, blinded, randomized controlled trial. ANIMALS: Eight hind limbs from canine cadavers. METHODS: The limbs were randomly allocated to two groups; software on (group I) and software off (group II). Eight anaesthetists with no previous experience of ultrasound-guided regional anaesthesia were recruited. Thirty-six procedures were carried out (18 per group). After sciatic nerve visualisation via ultrasonography, the anaesthetist introduced a needle guided by ultrasonography. When the tip of the needle was considered by the anaesthetist to be as close as possible to the nerve without touching it, 0.05 mL of methylene blue dye was injected. Parameters evaluated included: number of attempts to visualise the needle with ultrasonography, time spent to perform the technique, subjective evaluation of ease of needle visualisation, proximity of the tip of the needle to the nerve, and, at dissection of the leg, inoculation site of the dye in relation to the nerve. RESULTS: Significant differences between groups were identified in relation to the number of attempts (group I: median 1, IQR: 1 - 1 attempts versus group II: median 1, IQR: 1 - 4 attempts, p = 0.019), and the relationship between the dye and the nerve during hind limb dissection (72.2% of the nerves were stained in group I versus 16.6% in group II, p = 0.003). No significant difference between groups was observed with respect to the time taken to perform the procedure (group I: median 25.5, IQR: 18.4 - 44.3 seconds versus group II: median 35.7, IQR: 18.6-78.72 seconds, p = 0.31), subjective evaluation of the needle visualization (p = 0.45) or distance between the tip of the needle and the nerve as measured from the ultrasound screen (p = 0.23). CONCLUSIONS AND CLINICAL RELEVANCE: This study identified greater success rate in nerve staining when the needle enhancing software was used. The results suggest that the use of this technique could improve injection technique amongst inexperienced anaesthetists performing ultrasound-guided peripheral nerve blocks in dogs.

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