Evaluation of the eZono 4000 with eZGuide for ultrasound-guided procedures

Miniaturized electromagnetic tracking enables efficient ultrasound-navigated needle insertions

Ultrasound (US) has gained popularity as a guidance modality for percutaneous needle insertions because it is widely available and non-ionizing. However, coordinating scanning and needle insertion still requires significant experience. Current assistance solutions utilize optical or electromagnetic tracking (EMT) technology directly integrated into the US device or probe. This results in specialized devices or introduces additional hardware, limiting the ergonomics of both the scanning and insertion process. We developed the first ultrasound (US) navigation solution designed to be used as a non-permanent accessory for existing US devices while maintaining the ergonomics during the scanning process. A miniaturized EMT source is reversibly attached to the US probe, temporarily creating a combined modality that provides real-time anatomical imaging and instrument tracking at the same time. Studies performed with 11 clinical operators show that the proposed navigation solution can guide needle insertions with a targeting accuracy of about 5 mm, which is comparable to existing approaches and unaffected by repeated attachment and detachment of the miniaturized tracking solution. The assistance proved particularly helpful for non-expert users and needle insertions performed outside of the US plane. The small size and reversible attachability of the proposed navigation solution promises streamlined integration into the clinical workflow and widespread access to US navigated punctures.

Robust tip localization under continuous spatial and temporal constraints during 2D ultrasound-guided needle puncture

PURPOSE

During ultrasound-guided (US-guided) needle puncture for minimally invasive procedures, automated needle tip localization can help clinicians capture small tips in US images easily and precisely, providing them with obvious tip indicators on the screen and bringing them more confidence during the procedures. However, automated needle tip localization in US images is challenging due to serious interferences arising from all kinds of echoes.

METHODS

We propose a method that localizes needle tips under continuous spatial and temporal constraints in the real-time US frame stream. A temporal constraint is firstly acquired by detecting translational tip motion in motion-enhanced US images with a deep learning-based (DL-based) detector. A spatial constraint and candidate tip locations are obtained by detecting needle shafts and tips in the raw grayscale B-mode images with another DL-based detector. To provide continuous constraints, estimated tip velocity from acquired temporal constraint is used to predict tip locations in frames where no temporal or spatial constraint is detected. Finally, tip coordinates are precisely localized among candidate tips under the spatial and temporal constraints.

RESULTS

Experimental results evaluated on 1121 US images from porcine organ punctures, and 895 images from human thyroid punctures demonstrate that the proposed method is effective and efficient, surpassing existing methods. On porcine organ data, a 97.2% recall rate and a 91.9% precision rate on tip detection and 0.88 ± 0.70 mm root-mean-square error (RMSE) on tip localization were achieved. On the human thyroid data, which was not involved in the training, 86.5% recall, 84.3% precision and 0.92 ± 0.78 mm RMSE were achieved separately. The running speed of 14.5 frames per second was achieved only using a CPU.

CONCLUSION

The proposed method provides a more reliable solution for automated needle tip localization during US-guided needle puncture, being more robust to interferences. Fast running speed leads to its practicability in the real-time US stream.

Time-aware deep neural networks for needle tip localization in 2D ultrasound

PURPOSE

Accurate placement of the needle is critical in interventions like biopsies and regional anesthesia, during which incorrect needle insertion can lead to procedure failure and complications. Therefore, ultrasound guidance is widely used to improve needle placement accuracy. However, at steep and deep insertions, the visibility of the needle is lost. Computational methods for automatic needle tip localization could improve the clinical success rate in these scenarios.

METHODS

We propose a novel algorithm for needle tip localization during challenging ultrasound-guided insertions when the shaft may be invisible, and the tip has a low intensity. There are two key steps in our approach. First, we enhance the needle tip features in consecutive ultrasound frames using a detection scheme which recognizes subtle intensity variations caused by needle tip movement. We then employ a hybrid deep neural network comprising a convolutional neural network and long short-term memory recurrent units. The input to the network is a consecutive plurality of fused enhanced frames and the corresponding original B-mode frames, and this spatiotemporal information is used to predict the needle tip location.

RESULTS

We evaluate our approach on an ex vivo dataset collected with in-plane and out-of-plane insertion of 17G and 22G needles in bovine, porcine, and chicken tissue, acquired using two different ultrasound systems. We train the model with 5000 frames from 42 video sequences. Evaluation on 600 frames from 30 sequences yields a tip localization error of [Formula: see text] mm and an overall inference time of 0.064 s (15 fps). Comparison against prior art on challenging datasets reveals a 30% improvement in tip localization accuracy.

CONCLUSION

The proposed method automatically models temporal dynamics associated with needle tip motion and is more accurate than state-of-the-art methods. Therefore, it has the potential for improving needle tip localization in challenging ultrasound-guided interventions.

A novel electromagnetic guidance ultrasound system on radial artery cannulation: a prospective randomized controlled trial

Background

Radial artery cannulation can cause complications such as haematoma formation or thrombosis due to its small diameter. Recently, a novel ultrasound device equipped with an electromagnetic guidance system was introduced, showing the path and alignment of the needle during the procedure. The aim of this study was to investigate the effects of this novel system on both success and complication rates during radial artery cannulation under ultrasound guidance.

Methods

In this randomized controlled trial, 76 adults scheduled for neurosurgery requiring radial artery cannulation were recruited. In group E (n = 38), radial artery cannulation was performed using the electromagnetic guidance ultrasound system, whereas in group C (n = 38), the procedure was performed using conventional ultrasound guidance. The success rates of cannulation on the first attempt, cannulation times, number of attempts, and incidence of complications were compared between the two groups.

Results

There was a significant difference in the success rates on the first attempt between the two groups (group C = 78.9% vs. group E = 94.7%, P = 0.042). Incidences of posterior wall puncture and haematoma formation (group C = 8 vs. group E = 1; P = 0.028) were significantly lower in group E than in group C. The median cannulation time for successful attempts was comparable between groups.

Conclusions

Use of the novel electromagnetic guidance system resulted in a better success rate on the first attempt and a lower incidence of complications during radial artery cannulation.

Trial registration

This study was registered at http://cris.nih.go.kr (registration number: KCT0002476).

Standard Needle Magnetization for Ultrasound Needle Guidance: First Clinical Experiences in Fine-Needle Aspiration Cytology of Thyroid Nodules

Fine-needle aspiration cytology using a novel ultrasound needle guidance system on the basis of standard needle magnetization was consecutively performed in 30 (15 in-plane and 15 out-of-plane) suspicious thyroid nodules. Nondedicated, commercially available needles were used. The technical effectiveness and safety of the system were satisfying; system failures were observed in 2 cases. The needle tip could be (at least occasionally) visualized inside the thyroid nodule in 96%, and the subjective procedure ratings were excellent in 57%. The out-of-plane technique was significantly superior in both respects (P = .021 and .027, respectively). Standard needle magnetization ultrasound needle guidance was easy to apply and cost-effective and has the potential to improve fine-needle aspiration cytology performance.

Needle tip tracking for ultrasound-guided peripheral nerve block procedures-An observer blinded, randomised, controlled, crossover study on a phantom model

BACKGROUND

The Onvision needle tip tracking (NTT) is a new technology consisting of a needle with an ultrasound sensor close to the needle tip and a console for computerised signal processing. The aim of the study was to evaluate NTT technology during ultrasound-guided simulated peripheral nerve block procedures in a porcine phantom model.

METHODS

Forty anaesthesiologists performed in-plane and out-of-plane simulated nerve blocks with and without NTT guidance. The primary outcome measure was procedure time. Secondary outcomes were hand movements and the path length travelled by the hands measured by motion analysis, precision of the needle tip related to the target structure, success rates and violations of the target structure, and the participants confidence whether their procedure would be successful or not.

RESULTS

Procedure time was reduced from 66.7 (SD = 47.5) seconds to 43.8 (SD = 29.2) seconds when NTT was used for out-of-plane procedures (P = 0.002). The number of hand movements of the probe hand was 13.9 (SD = 30.2) with NTT and 22.8 (SD = 30.0) without NTT (P = 0.019). No significant differences were registered during the performance of in-plane procedures. The participants confidence in a presumed block success was increased with both in-plane procedures (8.50 (SD = 1.18) with NTT vs 7.65 (SD = 1.96), P = 0.004) and out-of-plane procedures (8.50 (SD = 1.09) vs 7.10 (SD = 1.89), P = 0.0001).

CONCLUSIONS

The new NTT technology significantly reduced the procedure time and the number of hand movements for ultrasound-guided out-of-plane PNB procedures. No significant differences were found for the in-plane procedures.

Ultrasound-guided central venous vascular access-novel needle navigation technology compared with conventional method: A randomized study

PURPOSE

Central venous catheter insertion is a common procedure in the intensive care setting. However, complications persist despite real-time ultrasound guidance. Recent innovation in needle navigation technology using guided positioning system enables the clinician to visualize the needle's real-time position and trajectory as it approaches the target. We hypothesized that the guided positioning system would improve performance time in central venous catheter insertion.

METHODS

A prospective randomized study was conducted in a single-center adult intensive care unit. In total, 100 patients were randomized into two groups. These patients underwent internal jugular vein central venous catheter cannulation with ultrasound guidance (short-axis scan, out-of-plane needling approach) in which one group adopted conventional method, while the other group was aided with the guided positioning system. Outcomes were measured by procedural efficacy (success rate, number of attempts, time to successful cannulation), complications, level of operators' experience, and their satisfaction.

RESULTS

All patients had successful cannulation on the first attempt except for one case in the conventional group. The median performance time for the guided positioning system method was longer (25.5 vs 15.5 s; p = 0.01). And 86% of the operators had more than 3-year experience in anesthesia. One post-insertion hematoma occurred in the conventional group. Only 88% of the operators using the guided positioning system method were satisfied compared to 100% in the conventional group.

CONCLUSION

Ultrasound-guided central venous catheter insertion via internal jugular vein was a safe procedure in both conventional and guided positioning system methods. The guided positioning system did not confer additional benefit but was associated with slower performance time and lower satisfaction level among the experienced operators.

One-Lung Flooding Enables Ultrasound-Guided Transthoracic Needle Biopsy of Pulmonary Nodules with High Sensitivity

Ultrasound-guided transthoracic needle biopsy (USgTTNB) can only be used for peripheral tumours that contact the pleura. Sonographic accessibility of the entire lung can be achieved using one-lung flooding. In this study, feasibility, sensitivity and complication rate of USgTTNB of lung nodules after one-lung flooding in an ex vivo and in vivo lung tumour model were assessed. USgTTNB was performed ex vivo after one-lung flooding in 10 resected human lung lobes containing carcinoma or metastasis. USgTTNB after one-lung flooding and simulation of a lung nodule was conducted in vivo in 5 animals. Transthoracic sonography and chest X-ray were obtained 30 min after reventilation. The lungs were examined macroscopically and histopathologically. The pathologic diagnosis was confirmed in 85.7% and 100% of tumours after first and second puncture attempts, respectively. The successful puncture rate in vivo was 90%. Neither pneumothorax nor bleeding was observed. One-lung flooding enables USgTTNB of lung nodules with a high sensitivity and minimal risk of complications in a pre-clinical model.

Toward dynamic lumbar puncture guidance using needle-based single-element ultrasound imaging

Lumbar punctures (LPs) are interventional procedures that are used to collect cerebrospinal fluid. Since the target window is small, physicians have limited success conducting the procedure. The procedure is especially difficult for obese patients due to the increased distance between bone and skin surface. We propose a simple and direct needle insertion platform, enabling image formation by sweeping a needle with a single ultrasound element at the tip. The needle-shaped ultrasound transducer can not only sense the distance between the tip and a potential obstacle, such as bone, but also visually locate the structures by combining transducer location tracking and synthetic aperture focusing. The concept of the system was validated through a simulation that revealed robust image reconstruction under expected errors in tip localization. The initial prototype was built into a 14 G needle and was mounted on a holster equipped with a rotation shaft allowing one degree-of-freedom rotational sweeping and a rotation tracking encoder. We experimentally evaluated the system using a metal-wire phantom mimicking high reflection bone structures and human spinal bone phantom. Images of the phantoms were reconstructed, and the synthetic aperture reconstruction improved the image quality. These results demonstrate the potential of the system to be used as a real-time guidance tool for improving LPs.