Echogenic Needle Research Articles

Automatic Robotic Steering of Flexible Needles from 3D Ultrasound Images in Phantoms and Ex Vivo Biological Tissue.

Robotic control of needle bending aims at increasing the precision of percutaneous procedures. Ultrasound feedback is preferable for its clinical ease of use, cost and compactness but raises needle detection issues. In this paper, we propose a complete system dedicated to robotized guidance of a flexible needle under 3D ultrasound imaging. This system includes a medical robot dedicated to transperineal needle positioning and insertion, a rapid path planning for needle steering using bevel-tip needle natural curvature in tissue, and an ultrasound-based automatic needle detection algorithm. Since ultrasound-based automatic needle steering is often made difficult by the needle localization in biological tissue, we quantify the benefit of using flexible echogenic needles for robotized guidance under 3D ultrasound. The "echogenic" term refers to the etching of microstructures on the needle shaft. We prove that these structures improve needle visibility and detection robustness in ultrasound images. We finally present promising results when reaching targets using needle steering. The experiments were conducted with various needles in different media (synthetic phantoms and ex vivo biological tissue). For instance, with nitinol needles the mean accuracy is 1.2mm (respectively 3.8mm) in phantoms (resp. biological tissue).

Novel 3D ultrasound system for midline single-operator epidurals: a feasibility study on a porcine model

BackgroundWe developed a real-time 3D ultrasound thick slice rendering technique and innovative Epiguide needle-guide as an adjunct to single-operator midline epidural needle insertions. Study goals were to determine feasibility of the technique in a porcine model and compare the visibility of standard and echogenic needles. MethodsThirty-four lumbar needle insertions were performed on six intact porcine spines ex vivo. Ultrasound scanning identified the insertion site and, using an Epiguide, the needle was guided into the epidural space through the ligamentum flavum in the midline plane, watched in real-time on the 3D ultrasound. Entry into the epidural space was judged by a loss-of-resistance technique. Needle visibility was rated by the anesthesiologist performing the technique using a 4-point scale; (0=cannot see, 1=poor, 2=satisfactory, 3=excellent), and later by an independent assessor viewing screenshots. The procedure was repeated at all lumbar levels using either the standard or echogenic needle. ResultsSuccessful loss-of-resistance to fluid was achieved in 76% of needle insertions; needle visibility with echogenic needles (94.2% rated satisfactory/excellent) was significantly better than with standard needles (29.4% satisfactory/excellent, P<0.0001). Successful loss-of-resistance was 93% when mean needle visibility was rated as ‘excellent’. Inter-observer agreement between assessors was ‘near-perfect’ (weighted kappa=0.83). ConclusionIt is feasible to perform 3D ultrasound-guided real-time single-operator midline epidural insertions, in a porcine model. Echogenic needles were found to consistently improve needle visibility; and improved needle visibility tended to increase successful entry into epidural space.

SU‐F‐J‐227: Accuracy of Passive Magnetic Ultrasound Needle Guidance in High‐ Fidelity Conventional and Novel Simulated Block Approach Phantoms

Purpose:The objective of this research was to demonstrate accuracy of a real‐time passive ultrasound magnetic needle guidance technology (NGT) and target localization algorithm using conventional anechogenic contact phantoms and a novel fluid‐filled hyperechogenic phantom simulating nerve block technique.Methods:Accuracy (mm to phantom target) was assessed by observing 35 medical practitioners (16 anesthesiologists and 19 residents) performing 560 needle procedures in high‐fidelity ex vivo porcine tissue phantoms. Each practitioner performed 8 tasks with GE Venue 50 magnetic NGT system with PinPoint GT (Bard Access Sys.) and 8 conventional echogenic needle (control) procedures under various conditions (#18/#22 needle gauge, IP/OOP approach, and hyperechogenic simulated block approach targets or anechogenic solid targets). Passes, user feedback, and ergonomics were also assessed.Results:Overlaid visual aids produced in real time (&lt;300 mS delay) by NGT enabled users to consistently perform with better accuracy than control echogenic needle guidance. Accuracy improved by 51.2% at 95% CI [29.8%, 66.7%] (P = 0.0008) among block approach phantoms and 51.4% at 95% CI [34.9%, 64.0%] (P &lt; 0.0001) among placement phantoms. Further, inadvertent contact with targets was reduced by NGT visualizations versus controls in both anesthesiologists (0 vs. 8 contacts; accuracy 2.0±1.7 vs. 4.13±6.7 mm) and novice users (3 vs. 12 contacts; accuracy 2.2±2.3 vs. 2.9±3.7 mm), respectively. Among novice users, NGT visualizations notably reduced quality‐compromising ergonomic observations compared to controls under equivalent conditions.Conclusion:NGT systems employing magnetic field generation and electromagnetic sensors to track needle position and orientation relative to a sonoanatomical target within a magnetic field have the potential to enable greater accuracy for complex needle placements and reduce unintentional needle contact, particularly in novice users. Further, NGT visualizations of needle tip and projected trajectory contribute to positive ergonomics and reducing quality‐compromising behaviors among operators, potentially reducing fatigue and needle progression error.This work was supported by funding provided by the GE Healthcare Ultrasound Business, Milwaukee, WI.

Modeling, Production, and Testing of an Echogenic Needle for Ultrasound-Guided Nerve Blocks.

We have designed, produced, and tested an echogenic needle based on a sawtooth pattern where the height of the tooth was 1.25 times the wavelength of the ultrasound transducer. A numeric solution to the time-independent wave equation (Helmholtz equation) was used to create a model of backscattering from a needle. A 21-gauge stainless steel prototype was manufactured and tested in a water bath. Backscattering from the needle was compared to theoretical predications from our model. Based on these results, an 18-gauge prototype needle was fabricated from stainless steel and tested in a pig cadaver. This needle was compared to a commercial 18-gauge echogenic needle (Pajunk Medical Systems, Tucker, GA) by measuring the brightness of the needle relative to the background of sonograms of a needle in a pig cadaver. The backscattering from the 21-gauge prototype needle reproduced the qualitative predictions of our model. At 30° and 45° of insonation, our prototype performed equivalently to the Pajunk needle. At 60°, our prototype was significantly brighter than the Pajunk needle (P = .017). In conclusion, we chose a model for the design of an echogenic needle and modeled it on the basis of a solution to the Helmholtz equation. A prototype needle was tested in a water bath and compared to the model prediction. After verification of our model, we designed an 18-gauge needle, which performed better than an existing echogenic needle (Pajunk) at 60° of insonation. Our needle will require further testing in human trials.

The Serratus Anterior Plane (SAP) Block: An Anatomical Investigation of the Regional Spread of Anesthetic Using Ultrasound‐guided Injection

The Serratus Anterior Plane (SAP) Block is a relatively novel approach to providing regional anesthetic to the lateral hemithorax. However, the spread of the block, which determines its utility in thoracic and upper abdominal surgeries, is unclear.To investigate its distribution and make recommendations for its clinical use, ultrasound‐guided SAP blocks were performed bilaterally on three fresh frozen cadavers (n=6) by an experienced anesthesiologist using a Sonosite M‐Turbo ultrasound machine (HFL38X/13‐6 MHz linear transducer). The ultrasound was used to count the ribs inferiorly from the clavicle until the level of rib 4, where the Serratus anterior muscle and Gerdy's ligament could be visualized. The insulated echogenic peripheral nerve block needle (21 gauge × 90 mm) was then inserted in‐plane along the midaxillary line, at the level of rib 4, just lateral to Gerdy's ligament and superficial to Serratus anterior. A total volume of 20 mL (methylene blue, 5% dextrose, 0.5% cellulose) was injected, with the methylene blue dye included to visualize the spread of injectate. Each cadaver was then dissected, allowing 15 minutes for the spread of the dye. The injection approach, viscosity and volume of fluid injected, and post‐injection wait period were designed to be comparable to clinical procedures.Of 6 completed SAP blocks, 1 block failed as the injection occurred into the axilla and Gerdy's ligament, restricting the spread of the dye to the axillary fat. The remaining 5 blocks were successful. Of these blocks, dissection results showed a trend in spread from the lateral cutaneous branches of T2 to T5 intercostal nerves, with variable spread to T6. The long thoracic nerve was stained in all successful blocks, and the thoracodorsal nerve was stained in 4 of the successful blocks. These nerves are especially important for the pain management of patients undergoing breast surgeries.The results of our study indicate that the SAP block's utility is limited to surgeries performed within T2–T5(T6) dermatomes and thus the upper lateral thoracic wall. This finding is in contrast to that of Blanco et. al1, who reported attaining anesthesia from T2–T9 in their volunteer study, which would allow the SAP block to be used in upper abdominal surgeries as well. A pin prick study will be completed to compare cadaver study findings with those attained from patients in the clinical setting.In addition, contrary to Blanco et. al, the authors of this study consider the SAP block to be a difficult block to achieve consistent wide spread anesthesia. It is recommended that anesthetists are provided with specific training including regional ultrasound anatomy and approach technique before attempting the block. The fascial plane superficial to the Serratus anterior muscle should also be hydrodissected using saline or local anesthetic before the block is delivered to ensure proper needle placement.

Surface-blended texturing of medical needles for friction reduction using a picosecond laser

The success of percutaneous procedures depends on the accuracy of the medical needle insertion. Reducing the insertion force and using better needle visualization during needle insertion can reduce needle placement errors. Surface texturing is frequently used to create micro-features on medical needle’s tip portion to improve the visibility in ultrasound-guided percutaneous procedures. However, these micro-features usually increase the friction between the needle and tissue because of stress concentrations. This paper explores a method for creating micro-features with blended edges on echogenic needles and studies the friction behavior between textured echogenic needles and phantom tissue to identify blended texture patterns that would minimize the friction during needle insertion. Laser surface texturing was used to create regular micro-circumferential channels and micro-corner-cube-like dimples along the needle’s axial direction. Variations of the overlap in the feed direction were used to blend the edges of micro-channels and micro-dimples with different fillet radii. Both needles with regular and blended surface textures were experimentally investigated through needle extraction experiments from phantom tissue. It was found that the blended textured needles with large fillet radii exhibit a much better friction behavior.

The Infiniti Plus ultrasound needle guidance system improves needle visualization during the placement of spinal anesthesia.

The Infiniti Plus ultrasound needle guidance system improves needle visualization during the placement of spinal anesthesia.

Ultrasound guided chronic pain interventions (Part II)

Henceforth, ultrasonography (US) is an indispensible imaging technique in regional anesthesia practice. With the guidance of US, various invasive interventions in chronic pain pathologies of the musculoskeletal system, peripheral and neuroaxial pathologies has become possible. The management includes diagnostic blocks as weel as radiofrequency ablation and institution of neurolythic agents. During these algologic interventions we are able to see the target tissue, the dispersion of the drug and all nearby vascular structures. Besides these the US also protects the team from ionic radiation that one encounters when using flouroscopy of computed tomography. Latest publication in this field show that applicability of US in chronic pain syndromes is rapidly expanding with a good future. The additional equipment (echogenic needles, 3-D US etc.) will also expands its applications in algology practice. This review highlights different applications of US in chronic pain conditions.

Comparative evaluation of the visibility and block characteristics of a stimulating needle and catheter vs an echogenic needle and catheter for sciatic nerve block with a low-frequency ultrasound probe

Background.Clear visibility of the needle and catheter tip is desirable to perform safe and successful ultrasound-guided peripheral nerve blocks. This can be challenging with deeper blocks in obese patients. This study compared the visibility of echogenic and non-echogenic block needles and catheters in proximal sciatic blocks when performed with a low-frequency curved probe. Methods.Seventy-eight patients undergoing total knee joint arthroplasty were randomized to receive an ultrasound-guided continuous sciatic nerve block using either a non-echogenic needle and stimulating catheter or an echogenic needle and echogenic non-stimulating catheter. Block needles in both groups were placed using both neurostimulation and ultrasound guidance, after which the catheter was positioned using either neurostimulation alone (Stimulating group) or imaging alone (Echogenic group). Three anaesthetists blinded to group allocation graded video clips recorded during the blocks for nerve, needle and catheter visibility. Performance characteristics and block parameters were also compared. Results.No significant differences between the two groups were observed with regard to needle or catheter visibility (P=0.516). The Stimulating group required more needle redirections (P=0.009), had a longer procedure time [Echogenic median 274 s vs Stimulating 344 s (P=0.016)], and resulted in greater patient discomfort (P=0.012). There were no significant differences between the two groups in terms of block onset or completion time. Conclusions.Use of echogenic needles and catheters reduced procedure time and patient discomfort compared with a stimulating catheter system. There were no differences in the visibility scores of the two systems. Clinical trial registristration.CTR Protocol ID: R-11-495, Clinical Trials.Gov ID: NCT 01492660.

317 Trial of Ultrasound-Guided Femoral Nerve Block for Isolated Femur Fractures Using Echogenic Needles

317 Trial of Ultrasound-Guided Femoral Nerve Block for Isolated Femur Fractures Using Echogenic Needles

Objective and subjective comparison of the visibility of three echogenic needles and a nonechogenic needle on older ultrasound devices

ObjectiveThis study evaluated the visibility of echogenic needles with older ultrasound devices in an in vitro phantom study. MethodsWe compared three echogenic needles from B. Braun (BB), Unisis (UN), and Hakko (HK) with a nonechogenic needle. Each needle was inserted into an ultrasound phantom 10 times at 30° and 45° with the bevels up. The captured images of the needle and background contrast were digitally analyzed, and the median of 10 insertions for each angle was calculated to determine objective needle visibility. Needle images were also shown to 12 anesthesiologists to evaluate subjective visibility on a five-point Likert scale. ResultsThe shafts of all the echogenic needles were significantly more objectively visible than the nonechogenic needles. Subjective visibilities of the BB and UN needles were significantly higher than that of the nonechogenic needle. Therefore, the BB and UN needles were judged to have more than fair subjective visibility. However, subjective visibility of the HK needle was consistently and significantly lower than that of the BB and UN echogenic needles. At 45°, the HK needle had nearly the same poor visibility as the nonechogenic needle. ConclusionThe results of our study indicate that the BB and UN needles are more visible than nonechogenic needles in an ultrasound phantom, even on older devices.

Ultrasound guided chronic pain interventions (Part I).

Recently, ultrasonography (US) is an indispensible imaging technique in regional anesthesia practice. With the guidance of US, various invasive interventions in chronic pain pathologies of the musculoskeletal system, peripheral and neuroaxial pathologies has become possible. The management includes diagnostic blocks as weel as radiofrequency ablation and institution of neurolythic agents. During these algologic interventions we are able to see the target tissue, the dispersion of the drug and all nearby vascular structures. Besides these the US also protects the team from ionic radiation that one encounters when using flouroscopy or computed tomography. Latest publications in this field show that applicability of US in chronic pain syndromes is rapidly expanding with a good future. The additional equipment (echogenic needles, 3-D US etc.) will also expand its applications in algology practice. This review highlights different applications of US in chronic pain conditions.

Needle Echogenicity in Ultrasound-Guided Lumbar Spine Injections: A Cadaveric Study

Background: Echogenicity of regional anesthesia needles has been tested on different preclinical models; however, previous studies were done in an ideal experimental setting utilizing highfrequency insonation and superficially located targets. Because steep-angle deep injections are typically required for spinal and other chronic pain procedures, and low-frequency transducers are used, further feasibility study is warranted. Objectives: To determine effectiveness of steep-angle deep injections, typically required for spinal and other chronic pain procedures. Study Design: Experimental laboratory study. Setting: Willed Body Program, University of Washington. Methods: In-plane lumbar spine procedures with 50° and 70° angles were performed on a human cadaver. The images and video clips of a non-echogenic (Quincke-type) and echogenic (SonoPlex, StimuQuick, and EchoStim) needle placements were presented to 3 blinded assessors who rated the needle visibility on a 4-point scale. The data was statistically analyzed to determine the differences in visibility between the needles with and without the digital image enhancement, and to compare the video clips to captured images. Results: ANOVA analysis demonstrated that overall SonoPlex was significantly better (P = 0.02) than other needles. SonoPlex maintained its superiority in the subset of facet joint injections (P = 0.02), followed by Quincke-type, then the StimuQuik, and EchoStim needles. In deep procedures, EchoStim was comparable with SonoPlex (P = 0.03), and they both were better than the other 2 needles. The enhanced images received higher rates, with a 0.6 point mean improved rating (P = 0). Limitations: This study is limited by choice of needles, number of experiments performed, and potential postmortem changes of echogenicity. Conclusions: The SonoPlex needle appeared to have better echogenicity in this study. While nonechogenic Quincke-type needle visibility was adequate in superficial placements, it was limited in deep injections. An imaging enhancement is effective in improving needle visibility and should be used whenever possible. Key words: Spinal injections, ultrasound, echogenic needle

Differences in tip visibility and nerve block parameters between two echogenic needles during a simulation study with inexperienced anesthesia trainees

Needle tip visualization during ultrasound-guided regional anesthesia (UGRA) is necessary for safety and efficacy. However, disruption of the image of the needle tip driven toward the target is a general problem, especially for beginners. The purpose of this study was to compare performance parameters between using the Sonoplex and Stimuplex D-Plus echogenic needles in a simulated ultrasound-guided interventional task by inexperienced anaesthesia residents. After a standardized training session, 28 anesthesiology residents performed simulated nerve blocks in a beef phantom with each needle. All ultrasound images were digitally stored for analysis. The absolute time the needle tip was in view, total procedure time, and angle of needle insertion were subsequently measured objectively by two single investigators. The procedures that used the Sonoplex echogenic needle had significantly better tip visibility and shorter total procedure time at insertion angles between 42° and 64° relative to the phantom surface. We have demonstrated that inexperienced users who used the Sonoplex echogenic needle were able to complete the procedure more quickly. Needles with improved visibility would be a very useful addition to UGRA for inexperienced users.

In Vitro Randomized Comparison of a Standard and Novel Echogenic Needle for Ultrasonography-Guided Renal Targeting

Urologists are becoming increasingly aware of the importance of pretreatment percutaneous renal biopsy of small renal cortical neoplasms. A barrier to the routine performance of ultrasonography-guided percutaneous renal biopsy has been the technical challenges associated with the procedure. We evaluated a new modified needle, which incorporates an echogenic needle tip designed to improve the needle tip's visibility under ultrasonographic visualization. We evaluated and compared the ultrasonographic imaging quality of the echogenic needle (EN) and a standard needle (SN). Forty-eight participants were recruited to perform ultrasonography-guided needle targeting and drainage of a simulated cyst within a phantom model. The simulated cysts were embedded in an opaque gel mold. Each participant was blinded to the type of needle being deployed and was asked to identify and aspirate the simulated cyst with each needle under ultrasonography guidance. Each needle was tested at three ultrasound-aiming angles, (0, 15, and 30 degrees). The quality of needle visibility under ultrasonographic imaging was assessed via a questionnaire, including needle preference and a visibility score (1-10) at each aiming angle. Participants were stratified by level of ultrasound experience. For each angle tested, the EN received higher visibility ratings. The mean visibility scores for the EN vs the SN were 6.44 vs 5.52 at 0 degrees (P=0.001), 7.77 vs 6.96 at 15 degrees (P=0.0004) and 8.33 vs 7.54 at 30 degrees (P=0.0001). Participants reported significantly greater comfort using the EN needle compared with the SN (P=0.001). These results held true regardless of the sequence of needle tested first. Also, there was a significant difference in visibility scores by angle (P=0.0001). Larger angles (30>15>0) resulted in higher scores. In this in vitro trial, the application of the EN improved needle visibility for users of all levels of experience. Clinical correlation is pending.

Compound Imaging Technology and Echogenic Needle Design

Needle visualization in ultrasound-guided regional anesthesia can be improved by using needles of echogenic design with higher rate of reflection of ultrasound waves. Imaging solutions such as compound imaging might further improve imaging of both needle and tissue; these effects have not yet been studied. We hypothesized that compound imaging would significantly improve needle visibility, regardless of the insertion angle or needle type used. The effects of compound imaging on needle artifacts and tissue imaging were also investigated. A total of 200 video clips of in-plane needle insertions were obtained in embalmed cadavers with a conventional needle and an echogenic needle at 5 different insertion angles, with both conventional B-mode ultrasound imaging and compound imaging technology. Visibility of the needle shaft and needle tip as well as the needle artifact rate were assessed by a blinded investigator on a 4-point ordinal scale. The effects on tissue image quality and speckle artifacts were also assessed. Stepwise linear regression was performed to differentiate effects on needle visibility scores. Imaging of the needle shaft and tip was significantly enhanced when compound imaging technology was used (P < 0.0001). Use of echogenically designed needles or shallow needle insertion angles improved visibility of both shaft and tip (both P < 0.0001). With compound imaging, there are fewer needle artifacts, and tissue imaging quality and speckle artifact rate are significantly improved. Compound imaging technology enhances needle imaging with both echogenic and conventional needles. Tissue imaging and speckle artifacts are also optimized. Echogenic needle design results in better needle visibility scores in both B-mode and compound imaging.

The importance of needle echogenity in ultrasound guided axillary brachial plexus block: a randomized controlled clinical study.

Objective: In this study we aimed to compare the echogenic needles and the nerve stimulation addition to non-echogenic needles in ultrasound guided axillary brachial plexus block for upper extremity surgery.Methods: 90 patients were enrolled to the study. The patients were allocated into three groups randomly: Group E (n=30): ultrasound guided axillary block using echogenic needle, Group N (n=30): ultrasound guided axillary block using non-echogenic needle, Group NS (n=30): ultrasound guided axillary block using non-echogenic needle with nerve stimulator assistance. Duration of block procedure, mean arterial pressure, heart rate, pulse-oximetry, onset time of sensory and motor block, duration of sensory and motor block, time to first analgesic use, total need for analgesics, postoperative pain scores, patient and surgeon satisfaction scores were recorded.Results: Duration of block procedure values were lower in group E and NS, sensory and motor block durations, were significantly lower in group N. Sensorial and motor block onset time values were found lower in group NS but higher in group N. Patient and surgeon satisfaction scores were found lower in group N.Conclusion: We conclude that ultrasound guided axillary block may be performed successfully using both echogenic needles and nerve stimulation assisted non-echogenic needles.

Needle Echogenicity in Sonographically Guided Regional Anesthesia

Needle visualization is important for sonographically guided regional anesthesia procedures. Needle characteristics that improve needle visualization are therefore important to anesthesiologists. This study compared several echogenic needle designs by defining characteristics of needle echogenicity and assessing regional anesthesiologist preferences for these characteristics across various needle angles. Twelve blinded regional anesthesiologists graded 5 randomized block needles (1 nonechogenic control and 4 echogenic) on 4 predefined characteristics (overall brightness of the needle, overall clarity of the needle, brightness of the needle tip, and clarity of the needle tip). In-plane needle images in a gel phantom were obtained at 4 needle angles (15°, 30°, 45°, and 60°). Participants rated specific needle characteristics for each needle at each angle and then ranked their overall needle preferences. Significant differences in all 4 needle characteristics were found across needle types (P< .01). Clarity of the needle tip was significantly associated with overall needle rank (P = .009). Other needle visualization characteristics were not significantly correlated with needle rank. The SonoPlex Stim needle (Pajunk Medical Systems, Tucker, GA) was rated highest in all 4 predefined needle characteristics as well as overall needle rank. This study shows that anesthesiologists prefer certain visual characteristics of needles used in sonographically guided regional anesthesia procedures. Specifically, needle tip clarity most closely predicted clinician needle preferences. These results support the idea that all echogenic needle designs do not uniformly enhance needle visualization. Further studies are needed to determine whether needles with superior tip clarity predict not only clinician preferences but also improved sonographically guided regional anesthetic outcomes.

Optimizing the safety and practice of ultrasound-guided regional anesthesia

Significant improvements have been made in the quality of ultrasound imaging, and it is now much easier to see nerves. However, the key to safe ultrasound-guided regional anesthesia is to be able to direct the needle to the target. This relies on good needle visibility. We review the recent advances that have been made in this crucial area. Echogenic needles can improve shaft and tip visibility independent of experience level, compensate for suboptimal scanning technique, allow steeper insertion angles, reduce technical difficulty, and increase both confidence and satisfaction by anesthesiologists. An echogenic needle encourages holding the probe in one place on the patient, only advancing the needle when it can be seen, hence reducing the likelihood of quality-compromising behaviors. The poor visibility of nonechogenic needles when inserted at steeper angles commonly causes the observer to underestimate the insertion depth of the needle. Significant differences in echogenicity are found when comparing the currently available needles. Good echogenic needles should increase safety, efficacy, and simplicity, and hopefully further drive the adoption of ultrasound-guided techniques, to the benefit of our patients.

Echogenic Regional Anaesthesia Needles: A Comparison Study in Thiel Cadavers

Ultrasound guidance is now the standard procedure for regional nerve block in anesthesiology. However, ultrasonic visualisation of needle manipulation and guidance within tissues remains a problem. Two new echogenic needles (Pajunk and Braun) have been introduced to anesthesiology clinical practice but evaluation has been restricted to preserved animal tissue. In this study, the visibility of both echogenic needles was compared with a standard nonechogenic needle in a Thiel cadaver model. A total of 144 intramuscular injections were made in the upper arm in-plane and out-of-plane to the ultrasound beam at four angles (30°, 45°, 60° and 75°). The visibility of the needle was assessed by two independent, blinded observers using a 5-point Likert ordinal scale. Weighted κ for interobserver agreement was 0.77 (95% confidence interval [CI]: 0.68–0.86). The Pajunk echogenic needle was more visible than the Braun standard needle in-plane (p = 0.04), and the Braun standard and Braun echogenic needles out-of-plane (p = 0.02). Independent predictors of visibility using logistic regression were needle (p < 0.001) and plane of insertion (p = 0.08), receiver operator characteristic (ROC) area under the curve 0.90. In conclusion, the Pajunk echogenic needle offers the best visibility for ultrasound-guided regional anesthesia.