Final Needle Tip Position Research Articles

Ultrasound-guided costovertebral joint injection-technique description and fluoroscopy and computerized tomography combined controlled cadaveric feasibility study.

To describe and assess the feasibility of an ultrasound-guided technique for intra-articular injection of the costovertebral joints, in an unembalmed cadaveric specimen, utilizing fluoroscopy and cone beam computerized tomography for confirmation of contrast spread and needle tip position, respectively. A single unembalmed cadaveric specimen was obtained. A single interventionist performed the placement of the needles under ultrasound guidance. Contrast dye was then injected through each of the needles under real-time fluoroscopy. Finally, the specimen was submitted to a cone beam computerized tomography with 3-dimensional acquisition and multiplanar reformatting to assess final needle tip position relative to the costovertebral joints. In total, 18 spinal needles were placed under ultrasound guidance. Fluoroscopy showed 4 distinct patterns of contrast spread: intra-articular in the costovertebral joint (13 levels in total), epidural (1 level), intra-articular in the facet joint of the target level (3 levels), and undetermined (1 level). Cone-beam computerized tomography confirmed 13 out of 18 needles to be adequately placed in the costovertebral joints (72% of the total) and 5 out of the 18 needles to be misplaced: 3 needles were placed in the facet joint of the target level, and 2 needles were placed in the epidural space. This study suggests that, when performed by experienced interventionists, this technique has an accuracy rate of 72%. Further studies are warranted before these results can be extrapolated to daily clinical practice.

Cervical Ultrasound Utilization in Selective Cervical Nerve Root Injection for the Treatment of Cervical Radicular Pain: a Review

This paper aims to review the available literature addressing the safety, accuracy, and efficacy of ultrasound-guided injections for cervical radicular pain. Ultrasound-guided injections remain a “partially blind technique” due to the inability to visualize relevant structures and the distribution of injectate. There remains a need for adequately powered studies evaluating the safety, accuracy, and effectiveness of ultrasound-guided steroid injections in the cervical spine. Fluoroscopy remains the best evidence-based image-guidance modality for injections into the cervical epidural space to treat cervical radicular pain. If ultrasound guidance is planned for treatment of cervical radicular pain, the authors recommend concomitant use of fluoroscopy guidance. Given the risk of inaccurate needle placement, physicians should retain fluoroscopic images prior to contrast injection to document the proper vertebral segment and final needle tip position. As epidural flow cannot be fully visualized with ultrasound, it is recommended to use fluoroscopy and, if needed, digital subtraction imaging to confirm the absence of intravascular injection. At a minimum, images should be saved post-contrast injection to document epidural flow.

Augmented Reality-Guided Lumbar Facet Joint Injections.

The aim of this study was to assess feasibility and accuracy of augmented reality-guided lumbar facet joint injections. A spine phantom completely embedded in hardened opaque agar with 3 ring markers was built. A 3-dimensional model of the phantom was uploaded to an augmented reality headset (Microsoft HoloLens). Two radiologists independently performed 20 augmented reality-guided and 20 computed tomography (CT)-guided facet joint injections each: for each augmented reality-guided injection, the hologram was manually aligned with the phantom container using the ring markers. The radiologists targeted the virtual facet joint and tried to place the needle tip in the holographic joint space. Computed tomography was performed after each needle placement to document final needle tip position. Time needed from grabbing the needle to final needle placement was measured for each simulated injection. An independent radiologist rated images of all needle placements in a randomized order blinded to modality (augmented reality vs CT) and performer as perfect, acceptable, incorrect, or unsafe. Accuracy and time to place needles were compared between augmented reality-guided and CT-guided facet joint injections. In total, 39/40 (97.5%) of augmented reality-guided needle placements were either perfect or acceptable compared with 40/40 (100%) CT-guided needle placements (P = 0.5). One augmented reality-guided injection missed the facet joint space by 2 mm. No unsafe needle placements occurred. Time to final needle placement was substantially faster with augmented reality guidance (mean 14 ± 6 seconds vs 39 ± 15 seconds, P < 0.001 for both readers). Augmented reality-guided facet joint injections are feasible and accurate without potentially harmful needle placement in an experimental setting.

Accuracy of image-guided percutaneous injection into a phantom spinal cord utilizing flat panel detector CT with MR fusion and integrated navigational software

PurposeTo evaluate the accuracy of percutaneous fluoroscopic injection into the spinal cord of a spine phantom utilizing integrated navigational guidance from fused flat panel detector CT (FDCT) and MR datasets....

Training Surgical Residents With a Haptic Robotic Central Venous Catheterization Simulator

Ultrasound guided central venous catheterization (CVC) is a common surgical procedure with complication rates ranging from 5 to 21 percent. Training is typically performed using manikins that do not simulate anatomical variations such as obesity and abnormal vessel positioning. The goal of this study was to develop and validate the effectiveness of a new virtual reality and force haptic based simulation platform for CVC of the right internal jugular vein. A CVC simulation platform was developed using a haptic robotic arm, 3D position tracker, and computer visualization. The haptic robotic arm simulated needle insertion force that was based on cadaver experiments. The 3D position tracker was used as a mock ultrasound device with realistic visualization on a computer screen. Upon completion of a practice simulation, performance feedback is given to the user through a graphical user interface including scoring factors based on good CVC practice. The effectiveness of the system was evaluated by training 13 first year surgical residents using the virtual reality haptic based training system over a 3 month period. The participants' performance increased from 52% to 96% on the baseline training scenario, approaching the average score of an expert surgeon: 98%. This also resulted in improvement in positive CVC practices including a 61% decrease between final needle tip position and vein center, a decrease in mean insertion attempts from 1.92 to 1.23, and a 12% increase in time spent aspirating the syringe throughout the procedure. A virtual reality haptic robotic simulator for CVC was successfully developed. Surgical residents training on the simulation improved to near expert levels after three robotic training sessions. This suggests that this system could act as an effective training device for CVC.

Contrast Spread in the Superoposterior Approach of Transforaminal Epidural Steroid Injections for Lumbosacral Radiculopathy.

ObjectiveTo observe the contrast spread in superoposterior transforaminal epidural steroid injection (SP TFESI) and investigate the correlation between spread patterns and efficacy.MethodsThirty-one patients with lumbosacral radiculopathy underwent single-level TFESI under fluoroscopy. The final needle tip position was targeted toward the SP quadrant of the intervertebral foramen. To observe the spread, 1 mL of contrast material was injected, followed by a steroid injection. The contrast spread was graded anteroposteriorly and vertically in the epidural space. The effect of SP TFESI was evaluated by proportional pain score reduction.ResultsLevels injected were L4-5 (n=20) and L5-S1 (n=11). Seventeen cases were lateral, and 14 were central herniated disc (HD). Baseline mean visual analog scale score was 6.23. Contrast dispersed dorsally in all the cases, and 45.2% cases showed a concurrent ventral spread. The proportion of the pain reduction after 2 weeks showed no difference between the two groups. In vertical spreading analysis, mean cephalic/caudal grades were 1.40/1.55 at L4-5 level and 1.73/1.64 at L5-S1 level. The HD location had no effect on contrast dispersion.ConclusionIn SP TFESI, ventral contrast spread did not guarantee a better effect; however, the extent of cephalic flow in ventral expansion group correlated with the proportion of pain reduction.

Intraneural injection of a test dose of local anesthetic in peripheral nerves – does it induce histological changes in nerve tissue?

Most anesthesiologists use the injection of a test dose of local anesthetic in order to evaluate the final needle tip position. Thus, the intraneural injection of a full dose can be avoided. The aim of this study was to analyze whether an intraneural injection of a test dose of bupivacaine could trigger histological changes. Intraneural injections under direct vision were performed in 40 brachial plexus nerves in seven anesthetized pigs. Tibial nerves served as positive and negative controls. Two milliliter of bupivacaine 0.5% was injected in three nerves on the left brachial plexus. For control of local anesthetic's toxicity Ringer's solution was applied intraneurally on the right side. After maintaining 48 h of general anesthesia, the nerves were resected. The specimens were processed for histological examination and assessed for inflammation (hematoxylin and eosin stain, CD68-immunohistochemistry) and myelin damage (Kluver-Barrera stain). The degree of nerve injury was rated on a scale from 0 (no injury) to 4 (severe injury). Statistical analysis showed no significant differences between the bupivacaine group [median (interquartile range) 1 (1-1.5)] and the Ringer's solution group [1 (0.5-2) P = 0.772]. Mild myelin alteration was found in 12.5% of all specimens following intraneural injection, irrespective of the applied substance. "In our experimental study, intraneural injection of 2 ml of bupivacaine or Ringer's solution showed comparable mild inflammation. Nevertheless, inflammation can only be prevented by strictly avoiding nerve perforation followed by intraneural injection, as mechanical nerve perforation is a key factor for evolving inflammation.

An analysis of 1505 consecutive patients receiving continuous interscalene analgesia at home: a multicentre prospective safety study.

Continuous interscalene brachial plexus block has been shown to be the most effective analgesic technique following shoulder surgery; however, its use is uncommon due to logistical and safety concerns related to ambulatory administration. We prospectively studied 1505 consecutive patients undergoing shoulder surgery who received continuous interscalene analgesia at home. Catheter removal was by the patient between postoperative days two and five. There were no major complications although 27% of patients reported mild dyspnoea, 13% hoarseness and 7% dysphagia. Twelve percent sought medical advice and 2% reported technical issues with the pump or tubing. Complications and technical issues were associated with patient age; weight; use of ultrasound or concomitant nerve stimulation as the endpoint for final needle tip position; local anaesthetic placement via the catheter or needle; whether a catheter-related intervention for pain relief was required in the recovery area; and the type of ambulatory pump. We conclude that this study supports the safety of this underused analgesic technique.

A Randomized Crossover Study Comparing a Novel Needle Guidance Technology for Simulated Internal Jugular Vein Cannulation

Despite ultrasound guidance for central line placement, complications persist, as exact needle location is often difficult to confirm with standard two-dimension ultrasound. A novel real-time needle guidance technology has recently become available (eZono, Germany) that tracks the needle during insertion. This randomized, blinded, crossover study examined whether this needle guidance technology improved cannulation of a simulated internal jugular (IJ) vein in an ultrasound phantom. One hundred physicians were randomized to place a standard needle in an ultrasound neck phantom with or without the needle guidance system. Video cameras were placed externally and within the lumens of the vessels to record needle location in real time. The primary outcome measured was the rate of posterior wall puncture. Secondary outcomes included number of carotid artery punctures, number of needle passes, final needle position, time to cannulation, and comfort level with this new technology. The incidence of posterior vessel wall puncture without and with needle guidance was 49 and 13%, respectively (P < 0.001, odds ratio [OR] = 7.33 [3.44 to 15.61]). The rate of carotid artery puncture was higher without needle navigation technology than with needle navigation 21 versus 2%, respectively (P = 0.001, OR = 12.97 [2.89 to 58.18]). Final needle tip position being located within the lumen of the IJ was 97% accurate with the navigation technology and 76% accurate with standard ultrasound (P < 0.001, OR = 10.42 [2.76 to 40.0]). Average time for successful vessel cannulation was 1.37 times longer without guidance technology. This real-time needle guidance technology (eZono) shows significant improvement in needle accuracy and cannulation time during simulated IJ vein puncture.

MR-guided vertebroplasty with augmented reality image overlay navigation.

To evaluate the feasibility of magnetic resonance imaging (MRI)-guided vertebroplasty at 1.5 Tesla using augmented reality image overlay navigation. Twenty-five unilateral vertebroplasties [5 of 25 (20%) thoracic, 20 of 25 (80%) lumbar] were prospectively planned in 5 human cadavers. A clinical 1.5-Teslan MRI system was used. An augmented reality image overlay navigation system and 3D Slicer visualization software were used for MRI display, planning, and needle navigation. Intermittent MRI was used to monitor placement of the MRI-compatible vertebroplasty needle. Cement injections (3 ml of polymethylmethacrylate) were performed outside the bore. The cement deposits were assessed on intermediate-weighted MR images. Outcome variables included type of vertebral body access, number of required intermittent MRI control steps, location of final needle tip position, cement deposit location, and vertebroplasty time. All planned procedures (25 of 25, 100%) were performed. Sixteen of 25 (64%) transpedicular and 9 of 25 (36%) parapedicular access routes were used. Six (range 3-9) MRI control steps were required for needle placement. No inadvertent punctures were visualized. Final needle tip position and cement location were adequate in all cases (25 of 25, 100%) with a target error of the final needle tip position of 6.1 ± 1.9 mm (range 0.3-8.7 mm) and a distance between the planned needle tip position and the center of the cement deposit of 4.3 mm (range 0.8-6.8 mm). Time requirement for one level was 16 (range 11-21) min. MRI-guided vertebroplasty using image overlay navigation is feasible allowing for accurate vertebral body access and cement deposition in cadaveric thoracic and lumbar vertebral bodies.

Intricacies of the Contralateral Oblique View for Interlaminar Epidural Access

To the Editor, Furman and colleagues present a good overview of the contralateral oblique view when performing interventions via the posterior epidural space ⇓. Indeed, this view is superior to the lateral view in visualizing the needle tip and may improve overall safety especially with cervical interventions. Ambiguity, however, remains about the appropriate angle and the distance the needle needs to be advanced beyond the ventral interlaminar line (VILL) before the epidural space is accessed. In this letter we would like to highlight these inconsistencies and look at the relationship of the angle used in the contralateral oblique view to the location of the needle tip. Furthermore, we would like to comment on the so-called “spinolaminar” line mentioned by Furman and colleagues. The degree of obliquity when employing the contralateral oblique view is of paramount importance. Final needle tip position in this view is a function of the …

Dynamic Needle Tip Positioning – Ultrasound Guidance for Peripheral Vascular Access. A Randomized, Controlled and Blinded Study in Phantoms Performed by Ultrasound Novices

The application of ultrasound-guidance for peripheral venous access is gaining popularity. It is possible to produce a short axis or a long axis sonographic view of the target vessel and apply an out-of-plane or in-plane needle tip approach. Our aim was to present the dynamic needle tip positioning technique and to estimate which approach is the most accurate for inserting the needle tip into the center of the target vessel. Fiftynine novices in ultrasound-guided peripheral vascular access participated. (A) a short axis view combined with an out-of-plane needle tip approach using dynamic needle tip positioning was compared to (B) a long axis view combined with an in-plane needle tip approach to a target vessel embedded in a gelatine phantom. The success rate of method (A) was significantly higher than method (B) (97 % versus 81 %). The distance between the center of the target vessel and the final needle tip position was significantly shorter for method (A) compared to method (B). The combined short axis and out-of-plane technique using dynamic needle tip positioning had a higher success rate and a shorter distance between the center of the target vessel and the needle tip compared to the combined long axis and in-plane technique.

Epidural Contrast Flow Patterns of Transforaminal Epidural Steroid Injections Stratified by Commonly Used Final Needle-Tip Position

To evaluate the relationship between commonly used final needle-tip positions and subsequent contrast flow and patient-reported pain relief in transforaminal epidural steroid injections (TFESIs). Retrospective cross-sectional study. Medical records of subjects (N = 83) having undergone a TFESI between January 2008 and January 2009 were reviewed to compare TFESIs using the superior-anterior (SA) vs. the superior-posterior (SP) quadrant. Outcome measures included ventral and dorsal epidural contrast flow as well as near-to-complete pain relief as measured by numerical rating scale pain score pre- and post-procedure. SA TFESIs were associated with greater ventral epidural contrast flow as compared with SP TFESIs (100% vs 61.4%, P < 0.001). SA TFESIs with ventral epidural contrast flow were also associated with flow to a greater number of vertebral levels than SP TFESIs with ventral epidural contrast flow (41% vs 14.8%, P < 0.001). SP TFESIs were associated with greater dorsal epidural contrast flow than SA TFESIs (95.5% vs 43.6%, P < 0.05). SA TFESIs were also associated with a larger proportion of patients who achieved near-to-complete pain relief (P < 0.05) and greater reduction than SP TFESIs in post-procedure pain score relative to pre-procedure (3.3 vs 1.5, P < 0.01). The evolution of TFESIs must balance both safety and efficacy. The efficacy of SA TFESIs is demonstrated to be superior to that of SP TFESIs with regards to ventral epidural flow and patient-reported pain relief. Further efforts should focus on demonstrating efficacy while optimizing safety.

A novel MR-guided interventional device for 3D circumferential access to breast tissue.

MRI is rapidly growing as a tool for image-guided procedures in the breast such as needle localizations, biopsy, and cryotherapy. The ability of MRI to resolve small (<1 cm) lesions allows earlier detection and diagnosis than with ultrasound. Most MR-guidance methods perform a two-dimensional compression of the breast that distorts tissue anatomy and limits medial access. This work presents a system for localizing breast lesions with 360 degrees access to breast tissue. A novel system has been developed to perform breast lesion localization using MR guidance that uses a 3D radial coordinate system with four degrees of freedom. The device is combined with a novel breast RF coil for improved signal to noise and rotates 360 degrees around the breast to allow medial, lateral, superior, and inferior access minimizing insertion depth to the target. Coil performance was evaluated using a human volunteer by comparing signal to noise from both the developed breast RF coil and a commercial seven-channel breast coil. The system was tested with a breast-shaped gel phantom containing randomly distributed MR-visible targets. MR-compatible localization needles were used to demonstrate the accuracy and feasibility of the concept for breast biopsy. Localization results were classified based on the relationship between the final needle tip position and the lesion. A 3D bladder concept was also tested using animal tissue to evaluate the device's ability to immobilize deformable breast tissue during a needle insertion. The RF breast coil provided signal to noise values comparable to a seven-channel breast coil. The needle tip was in contact with the targeted lesion in 89% (25/28) of all the trials and 100% (6/6) of the trials with targeted lesions >6 mm. Target lesions were 3-4 mm in diameter for 47% (13/28), 5-6 mm in diameter for 32% (9/28), and over 6 mm in diameter for 21% (6/28) of the trials, respectively. The 3D bladder concept was shown to immobilize a deformable animal tissue phantom during needle insertion. It is concluded that the MR-guidance system accurately localizes small targets on the order of 3-4 mm in a breast phantom with 360 degrees rotational access.

Precision targeting of liver lesions using a novel electromagnetic navigation device in physiologic phantom and swine

Radiofrequency ablation of primary and metastatic liver tumors is becoming a potential alternative to surgical resection. We propose a novel system that uses real-time electromagnetic position sensing of the needle tip to help with precision guidance into a liver tumor. The purpose of this study was to evaluate this technology in phantom and animal models. Using an electromagnetic navigation device, instrumented 18 g needles were advanced into radioopaque tumor targets in a respiratory liver phantom. The phantom featured a moving liver target that simulated cranio-caudal liver motion due to respiration. Skin-to-target path planning and real-time needle guidance were provided by a custom-designed software interface based on pre-operative 1 mm CT data slices. Needle probes were advanced using only the electromagnetic navigation device and software display. No conventional real-time imaging was used to assist in advancing the needle to the target. Two experienced operators (interventional radiologists) and two inexperienced ones (residents) used the system. The same protocol was then also used in two anesthetized 45 kg Yorkshire swine where radioopaque agar nodules were injected into the liver to serve as targets. A total of 76 tumor targeting attempts were performed in the liver phantom, and 32 attempts were done in the swine. The average time for path planning was 30 s in the phantom, and 63 s in the swine. The median time for the actual needle puncture to reach the desired target was 33 s in the phantom, and 42 s in the swine. The average registration error between the CT coordinate system and electromagnetic coordinate system was 1.4 mm (SD 0.3 mm) in the phantom, and 1.9 mm (SD 0.4 mm) in the swine. The median distance from the final needle tip position to the center of the tumor was 6.4 mm (SD 3.3 mm, n=76) in the phantom, and 8.3 mm (SD 3.7 mm, n=32) in the swine. There was no statistical difference in the planning time, procedure time, or accuracy of needle placement between experienced and inexperienced operators. The novel electromagnetic navigation system allows probe delivery into hepatic tumors of a physiologic phantom and live anesthetized swine. The system allows less experienced operators to perform equally well as experienced radiologists in terms of procedure time and accuracy of needle probe delivery.