Percutaneous Needle Placement Research Articles

CT Navigation for Percutaneous Needle Placement: How I Do It

CT Navigation for Percutaneous Needle Placement: How I Do It

AIUM Official Statement: Guidelines for Cleaning and Preparing External- and Internal-Use Ultrasound Transducers and Equipment Between Patients as Well as Safe Handling and Use of Ultrasound Coupling Gel.

Journal of Ultrasound in MedicineEarly View Guidance paperFree Access AIUM Official Statement: Guidelines for Cleaning and Preparing External- and Internal-Use Ultrasound Transducers and Equipment Between Patients as Well as Safe Handling and Use of Ultrasound Coupling Gel First published: 19 January 2023 https://doi.org/10.1002/jum.16167AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Adequate transducer preparation is mandatory to protect patients from potential infection. The level of preparation depends on the type of examination performed. Preparation of external transducers between patients requires a low-level disinfection (LLD) process. Preparation of internal transducers between patients requires routine mandatory high-level disinfection (HLD) and the use of a high-quality single-use transducer cover during each examination. Users should consult a transducer's manufacturer instructions for disinfecting devices. Barriers used for internal and interventional percutaneous procedures must be single-use transducer covers that meet the sterility requirements of the procedure. For all chemical disinfectants, precautions must be taken to protect workers and patients from the toxicity of the disinfectant. Sterile single-use gel packets should be used when infection is a concern. If cross-contamination is a concern, non-sterile single-use gel packets should be used. For all other situations, multidose containers may be used. Dry heat should be used to heat gel where medically needed. LLD cleaning of equipment is a significant part of interrupting the cross-contamination chain. The cleaning frequency is dictated by operator and patient exposure to microbial activity. Following guidelines other than Ultrasound Original Equipment Manufacturers' (OEM) instructions for use (IFU) may lead to transducer damage1 and may negatively affect diagnostic results.2, 3 Regular interval inspection of ultrasound scanners and transducers (connector, cable, housing, acoustic lens) is recommended to ensure performance. Imaging with a tissue-mimicking phantom may help reveal imaging degradation. The AIUM does not endorse or promote any specific commercial products. It is the responsibility of each entity to follow transducer manufacturer guidelines and applicable infection control recommendations. Changes due to COVID-19 Outbreak Level of disinfection: For external and interventional procedures, low-level disinfection is effective per CDC guidelines.4 Currently, EPA-approved disinfectants for use against SARS-CoV-2, which causes COVID-19, can be found online.5 If LLD agents are depleted, additional cleaning should include soap and water.4 However, this does not complete the disinfection.4 If indicated but no transducer covers are available, medical gloves or other physical barriers (eg, compatible medical dressings) should be used. Education and execution: Dissemination of cleaning guidelines is essential and so is their proper execution.6 Equipment: Cleaning involves all ancillary equipment utilized during the procedure at hand. In addition to LLD cleaning, a cover sheet may be used as a physical barrier between the keyboard/console and the operator. If possible, use a dedicated system (scanner and transducers) for COVID-19, positive or suspected, patients. COVID-19 is viable on plastic surfaces for up to 72 hours.7 Special attention needs to be paid to COVID-19 and other respiratory infection cases requiring aerosolization procedures (eg, mechanical ventilation, aerosolization application, etc). In such cases, a transducer cover should be used, and the entire equipment requires full LLD (top to bottom) as pathogens are likely to become airborne. Always follow manufacturer guidance and institutional guidelines. Sections Procedural guidelines for transducer cleaning and preparation New literature and other relevant guidelines Safe handling and use of ultrasound coupling gel Safe handling of ultrasound scanners and other equipment Prevent misdiagnosis due to the use of damaged ultrasound transducers Section I: Procedural Guidelines for Transducer Cleaning and Preparation Procedural Graphics (Figure 1). Figure 1Open in figure viewerPowerPoint Transducer cleaning process. Introduction The purpose of the first section of this document is to provide guidance regarding the cleaning and preparation of ultrasound transducers. Some manufacturers use the term “probes” or “imaging arrays.” Medical instruments fall into different categories with respect to their potential for pathogen transmission. Therefore, different types of medical instruments require different cleaning methods. The most critical instruments are those that are intended to penetrate skin or mucous membranes, such as scissors, forceps, tweezers, or hemostats. These require sterilization. Less critical instruments (often called “semicritical” instruments) that simply come into contact with mucous membranes, such as endocavitary transducers, require HLD rather than sterilization. “Noncritical” devices that come into contact with intact skin but not mucous membranes, such as blood pressure cuffs, a stethoscope, or external transducers, require LLD. External transducers that only come into contact with clean, intact skin are considered noncritical devices and should be cleaned after every use, as described below in number 1. External transducers that come into contact with contaminated skin (such as skin infections) should be covered with a single-use transducer cover. Transducers for interventional percutaneous procedures that are used for percutaneous needle or catheter placement, such as vascular access, thoracentesis, paracentesis, arthrocentesis, pericardiocentesis, lumbar puncture, or ultrasound-guided regional/local anesthesia, should be cleaned using LLD and be used in conjunction with a single-use transducer cover. Such a cover must warrant protection against human viruses, including human immunodeficiency virus, human papillomavirus (HPV), hepatitis B, and others of clinical significance. The level of transducer cover sterility is dictated by the level of procedure sterility. For example, clean procedures requiring nonsterile transducer covers include peripheral vascular intravenous line placement, whereas full sterility procedures requiring full sterile transducer covers include percutaneous biopsies. Transducer covers can be commercial transducer sheaths or condoms as long as they fulfill institutionally defined infection control guidelines and procedure sterility requirements. If contamination of covered transcutaneous transducers with blood or other bodily fluids occurs, see steps in paragraph 2a of the next section. Internal transducers should be covered with a single-use transducer cover, as described below, when feasible. The level of transducer cover sterility is dictated by the level of procedure sterility. These transducers are therefore classified as semicritical devices. Ultrasound Transducer Cleaning and Preparation The following specific recommendations are made for the cleaning and preparation of all ultrasound transducers. For the protection of the patient and the health care worker, all internal examinations should be performed with the operator properly gloved throughout the procedure. Transducers need to be cleaned after each exam by using all of the following steps proposed by Abramowicz et al8: Cleaning of all transducers—Disconnect the transducer from the ultrasound scanner as appropriate. After removal of the transducer cover (when applicable), remove bulk gel or debris from the transducer. Consider the use of a small brush, especially for crevices and areas of angulation, depending on the design of the particular transducer. Use a damp gauze pad or other soft cloth and a small amount of mild nonabrasive liquid soap, eg, household dishwashing liquid, or use a wipe to remove any remaining gel (film). Disinfection can be (a) low-level or (b) high-level: Disinfection of all transducers in external procedures, as well as interventional percutaneous procedures, should undergo LLD. If contamination of covered transcutaneous transducers with blood or other bodily fluids occurs, it can be eliminated with low-level disinfectants that are effective against mycobacteria and bloodborne pathogens (including hepatitis B virus, hepatitis C virus, and HIV).9-13 Human hands are always cleaned with LLD and covered with gloves.14 Disinfection of all internal transducers (eg, transvaginal, transrectal, and transesophageal transducers), as well as intraoperative transducers, require HLD before they can be used on another patient. High-level chemical disinfectants rely on clean and dry surfaces as wet surfaces dilute the disinfectant; therefore, always dry the transducer before performing HLD. Chemical sterilants used for shorter exposure periods for internal transducer disinfection can also be part of the HLD process per CDC guidelines.9 Note: An obvious disruption in transducer cover integrity does not require modification of this protocol. Because of the potential disruption of the barrier sheath, HLD with chemical agents is necessary. The guidelines herein take into account possible transducer contamination due to a disruption in the barrier sheath. Rinsing—Depending on the employed disinfection agent, the transducer should be thoroughly rinsed and dried after disinfection, following manufacturer guidelines. Storing—Transducers need to be stored in accordance with their disinfection level. Remove and dispose of gloves, and wash hands. High-level liquid disinfection is required to ensure further statistical reduction in the microbial load. Examples of such high-level disinfectants are listed in Table 1. A complete list of Food and Drug Administration (FDA)-cleared liquid sterilants and high-level disinfectants is available online,2 and other agents are under investigation. To achieve HLD, the practice must meet or exceed the listed “High-Level Disinfectant Contact Conditions” specified for each product. Users should be aware that not all approved disinfectants on this list are safe for all ultrasound transducers. Table 1. Sterilants and High-Level Disinfectants Listed by the FDA Name Composition/Action Glutaraldehyde Organic compound (CH2(CH2CHO)2) Antimicrobial (induces cell death by cross-linking cellular proteins; usually used alone or mixed with formaldehyde) Hydrogen peroxide Inorganic compound (H2O2) Antiseptic and antibacterial (a very strong oxidizer with oxidation potential of 1.8 V) Peracetic acid Organic compound (CH3CO3H) Antimicrobial (high oxidation potential) Ortho-phthalaldehyde Organic compound (C6H4(CHO)2) Antimicrobial (strong binding to outer cell wall of contaminant organisms) Hypochlorite/hypochlorous acid Inorganic compound (HClO) Antimicrobial (myeloperoxidase-mediated peroxidation of chloride ions) Phenol/phenolate Organic compound (C6H5OH) Antimicrobial Hibidil Chlorhexidine gluconate (C22H30Cl2N10) Antiseptic Immersion of transducers in fluids requires attention to the individual device's ability to be submerged. Although some transducers as well as large portions of the cable may safely be immersed up to the transducer's connector, only the transducers of others may be submerged. Some manufacturers also note that the crystals of the array may be damaged if the transducer rests or impacts the bottom of the container, instead of being suspended in the disinfectant. Before selecting a method of disinfection, consult the manufacturer's guidelines regarding the compatibility of potential disinfecting agents with a specific transducer. Relevant information is available online and in device manuals. Additionally, not all transducers can be cleaned with the same cleaning agents. Although some agents are compatible with all transducers of a given manufacturer, others must be limited to a subset of transducers. The CDC recommends environmental infection control in the case of Clostridium difficile, consisting of “meticulous cleaning followed by disinfection using hypochlorite-based germicides as appropriate.”6 A hydrogen peroxide nanodroplet emulsion might provide an effective high-level disinfectant without toxicity. The Occupational Safety and Health Administration as well as the Joint Commission (Environment of Care Standard IC 02.02.01 EP 9) have issued guidelines for exposure to chemical agents, which might be used for ultrasound transducer cleaning. Before selecting a high-level disinfectant, users should request the Material Safety Data Sheet for the product and make sure that their facility is able to meet the necessary conditions to minimize exposure (via inhalation, ingestion, or contact through skin/eyes) to potentially dangerous substances. Proper ventilation, a positive-pressure local environment, and the use of personal protective devices (eg, gloves and face/eye protection) may be required. Low Resource Settings Users may be in settings, where resources are limited, and thus, cleaning and disinfection cannot be executed as laid out herein. These settings may include pandemics, supply chain disruptions, and resource-disadvantaged regions. Providers are encouraged to execute guidelines to the extent possible given their setting. Providers should weigh the benefit of use of ultrasound for imaging or guidance, and the eventual risk that is introduced due to cleaning and disinfection at a lower level than recommended. Conclusions The current literature points to the need for education on the proper use of transducer cleaning agents and procedures. It also points to the need of HLD for internal transducers (endocavitary) due to the risk of infection with HPV, for example. Contrary to that, use of external transducers on intact skin does not show an increased infection risk in conjunction with LLD. Prudent use of ultrasound includes guidance for interventional percutaneous procedures. In this case, the use of sterile gel and single-use protective covers (level of sterility dictated by the procedure sterility classification) justifies subsequent LLD, analogous to institutional health care guidelines for the use of gloves and LLD hand disinfection for medical personnel. Section II: New Literature and Other Relevant Guidelines Background Kac et al15 examined endocavitary transducers and found them persistently contaminated despite the use of transducer covers. They concluded that transducers may carry pathogens, including HPV, unless properly disinfected between examination sessions. For disinfection, they recommend an antiseptic-impregnated towel as well as a type-C ultraviolet light. Adhikari et al16 compared infection rates between ultrasound-guided and traditionally placed peripheral intravenous lines. A nonsterile glove was used as a barrier between the ultrasound transducer and the patient, and coupling was achieved using a bacteriostatic lubricant. Transducers were cleaned between patients using LLD. They concluded that both showed low infection rates (0.52% ultrasound and 0.78% traditional; n = 402 each; P = .68) and that there was no increased infection rate with ultrasound guidance. The Spaulding classification17 is inconsistent with the results of this study. Casalegno et al18 stated that a considerable number of endocavitary transducers are infected with high-risk HPV despite LLD and recommend that endocavitary transducers should be high-level disinfected (2.5% of transducers showed high-risk HPV after use and 1.8% before use; n = 198). Westerway et al19 examined 171 swabs of transabdominal and transvaginal transducers, of which 60% and 14% were found to show evidence of bacterial contamination, respectively. After LLD, both showed approximately a 4% likelihood of contamination. Westerway and Basseal6 also investigated if appropriate training was received and if cleaning procedures were followed. They found that 60% of respondents (n = 188) failed to receive adequate training before using any cleaning product. In addition, 33% had no access to written infection control policies for either transducers or ultrasound scanners (keyboard, connectors, cables, etc). Westerway and Basseal20 also investigated specifically the Australasian medical ultrasound practice. They found that only Ten percent of 392 users cleaned their keyboards after each patient. Fifty-six percent cleaned it once a day and 21% once per week.20 The machine cord was cleaned after each patient by 35% of all users (n = 393) and once a day by 32%. Fifteen percent cleaned it once a week. They concluded that education and updated guidelines may remedy this situation. In 2013, Seki et al21 traced an institutional nosocomial outbreak of multidrug-resistant Pseudomonas aeruginosa to a transesophageal echocardiogram transducer, specifically a 5-mm defect on the insertion tube, 15 cm from the end of the device. While the transducer was cleaned by way of centralized sterilization, the mechanical defect retained bacterial contamination. No transducer sheath was used. In the same year, Sartoretti et al22 compared the bacterial load on ultrasound transducers (n = 36), bus poles (n = 11), and toilets (n = 10). Before training, 53 colony-forming units (CFU) were found in cultures from transducers, while 0 CFU were found after training. Bus poles and toilets showed 28 CFU (P = .772) and 4 CFU (P = .055), respectively. Thus, training was key in improving healthcare-associated infections. Gottlieb et al23 acknowledged that the use of ultrasound for intravenous line placement adds a potential source for infection. However, they concurrently highlighted studies concluding that ultrasound-guided peripheral intravenous line placement reduces the need for central venous catheter placement in up to 80% of patients.24-27 Abramowicz et al8 provided cleaning guidelines for transvaginal transducers on behalf of the World Federation for Ultrasound in Medicine and Biology Safety Committee. They listed several HLD methods. Of these methods, only chlorine dioxide and a vaporized hydrogen peroxide system have been reported to effectively remove HPV. However, the supporting evidence for the latter method was based on several studies paid for by grants from its manufacturer. The Ultrasound Working Group of the European Society of Radiology released best-practice recommendations for infection prevention and control in ultrasound.28 They stated that for ultrasound transducers with protective covers that are in contact with mucous membranes or any body fluids (including interventional procedures, injections, tissue sampling, use in the theater, etc) require HLD. Protective barriers, such as medical gloves, are regulated by an acceptable quality level (AQL). The AQL is the maximum percentage of defective items permitted in a regulated product. Hence, the AQL may also mean the acceptable quality limit. The Center for Devices and Radiological Health in the Office of Device Evaluation at the FDA uses the AQL to define the acceptance level for medical gloves (21CFR800.20).29 Similarly, condoms, which are also mechanical protective barriers, are regulated by the AQL, and the World Health Organization (WHO) provides an AQL to set limits for their quality.30 Practitioners should be aware that condoms have a 10-fold stricter AQL (0.25%, WHO) compared to standard examination gloves (2.5%, FDA). They even exceed the AQL of surgical gloves (1.5%, FDA). Users should be aware of latex sensitivity issues and have non–latex-containing barriers available. In addition, transducer covers with pore sizes of less than 30 nm are now available. They effectively block most viruses, including HPV. One should perform HLD of the internal transducer between each use and employ an adequate transducer cover as a protective barrier. CDC Definitions According to the CDC Guideline for Disinfection and Sterilization in Healthcare Facilities:6 “Cleaning is the removal of visible soil (e.g., organic and inorganic material) from objects and surfaces and normally is accomplished manually or mechanically using water with soap or enzymatic products. Thorough cleaning is essential before HLD and sterilization because inorganic and organic material that remains on the surfaces of instruments interfere with the effectiveness of these processes.” “Disinfection describes a process that eliminates many or all pathogenic microorganisms, except bacterial spores.” Low-Level Disinfection—Destruction of most bacteria, some viruses, and some fungi. Low-level disinfection will not necessarily inactivate Mycobacterium tuberculosis or bacterial spores. Intermediate-Level Disinfection—Inactivation of M Tuberculosis, bacteria, most viruses, most fungi, and some bacterial spores. High-Level Disinfection—Destruction/removal of all microorganisms, except bacterial spores. “Sterilization describes a process that destroys or eliminates all forms of microbial life and is carried out in healthcare facilities by physical or chemical methods. Steam under pressure, dry heat, ethylene oxide (EtO) gas, hydrogen peroxide gas plasma, and liquid chemicals are the principal sterilizing agents used in health care facilities. When chemicals are used to destroy all forms of microbiologic life, they can be called chemical sterilants. These same germicides used for shorter exposure periods also can be part of the disinfection process (i.e., HLD).”6 Intersocietal Position Statement Several organizations addressed the issue of disinfection of transcutaneous ultrasound transducers used for percutaneous procedures or for the purpose of monitoring other invasive procedures. They recommend cleaning and LLD (including disinfectants that are effective against mycobacteria and bloodborne pathogens) for the reprocessing of transducers used for the above purposes.31 Section III: Safe Handling and Use of Ultrasound Coupling Gel Background Infection control is an integral part of the safe and effective use of ultrasound in medicine. For example, guidelines are in place for transducer disinfection to reduce the risk of iatrogenic and nosocomial infections. Although aspects of ultrasound coupling gel management and administration have been implicated in outbreaks of nosocomial infections with a variety of pathogenic organisms, recommendations for reducing gel-related infections vary (see Clinician Outreach and Communication Activity safety communication and Health Canada alert in the “Related Websites” section).32 The purpose of this document is to provide guidance regarding ultrasound coupling gel use to minimize risks of iatrogenic or nosocomial infections.33 Recommendations Practices and institutions should adopt an infection control policy regarding the use of ultrasound coupling gel and ensure that appropriate staff are educated regarding this policy. Sterile Gel Sterile single-use gel packets are preferable to nonsterile gel when infection is a concern. Such situations include but are not limited to: All invasive procedures that pass a device through a tissue (eg, needle aspiration, needle localization, and tissue biopsy); All ultrasound examinations performed on neonates; and All ultrasound examinations or procedures performed on nonintact skin or near fresh surgical sites. Sterile or bacteriostatic gel should be considered for endocavitary examinations performed on intact mucous membranes (eg, esophageal, gastric, rectal, and vaginal). Nonsterile Gel Single-use gel packets or multidose containers may be used. If multidose containers are used, care should be taken to: Discard and replace multidose containers when empty; these should not be refilled; Appropriately seal the container when not in use; and Avoid direct contact between the gel container dispensing tip and any persons or instrumentation, including the ultrasound transducer. If gel is to be used on a patient who is under droplet or contact precautions (such as COVID-19), discard the multidose container after use, or use a single-use gel packet. Gel Warming Dry heat should be the only method used to warm gel. Gel warmers should be cleaned and disinfected regularly according to the manufacturers' and infection-control policy's requirements. Section IV: Safe Handling of Scanner and Other Equipment Users should follow institutionally defined infection control guidelines for cleaning of ultrasound scanners, cables, connectors, and other equipment. The extent to which equipment needs to be cleaned is dictated by its exposure to the operator and the patient. Typically, this includes the ultrasound scanner console, its handles, the transducer cable and connector, gel containers, and the patient bed. Institutional infection control guidelines may also require a full scanner wipe down, for example, for scanning in operating rooms. CDC guidelines for healthcare facilities (2017) address microbicidal activity of quaternary ammonium compounds (LLD) specifically for keyboards.7, 34 Equally important to creating cleaning guidelines is their dissemination to and subsequent execution by the operators. Westerway and Basseal6 highlighted the lack of appropriate cleaning and disinfection training for a significant number of their survey responders. Approximately half of them did not undergo training for either purchased ultrasound equipment or cleaning products. The responses regarding actual equipment cleaning were similar. Approximately 50% cleaned the transducer cord after each patient, but only 15% cleaned the keyboard. Most operators (57%) cleaned the keyboard daily, but 7.6% never did. Even in a non-critical setting, ie, external transducers, not cleaning a keyboard is concerning. The cleaning frequency and level of sterility of ancillary equipment should follow institutional infection control guidelines for the procedure at hand and are dictated by operator and patient exposure to microbial activity. For example, for surgical procedures, equipment should be disinfected prior to the procedure (to prevent infection), whereas for COVID-19 patients, it should be disinfected after the procedure (to prevent cross-contamination). Section V: Preventing Misdiagnosis due to the Use of Damaged Ultrasound Transducers Without proper care of ultrasound probes and equipment, ultrasound imaging performance can be reduced. One study found the performance of probes in routine clinical practice was compromised in some manner in 39.8% of the evaluated transducers.2 Another study, examining the failure rate of ultrasound systems in a hospital setting, showed that 12% of total failures were due to the ultrasound system and 88% were due to the transducer.1 It was also reported that lens delamination or some form of element damage in the transducer array caused transducer failures and compromised performance.2, 3 Damaged transducers due to dead elements or elements with reduced sensitivity may reduce resolution and penetration, increase the noise floor, cause Doppler velocity errors, produce flow direction ambiguity, and increase spectral broadening. One of the causes of damage associated with cleaning and disinfection in this study is the use of automated reprocessing devices that have not been validated by manufacturers. For this reason, researchers found that certain transducers, such as endocavitary transducers, had higher failure rates. Using chemicals and reprocessing protocols or methods not validated by the responsible OEM may potentially damage a given transducer and present a patient safety issue or produce a nondiagnostic study. Even when following the cleaning, disinfection, and sterilization guidelines provided by various clinical societies, damage to ultrasound transducers may occur.1 It is essential, therefore, to both strictly follow the OEM transducer reprocessing guidance and inspect the transducer prior to clinical scanning for changes in visual appearance and function to ensure the transducer appears fully functional and clinically efficacious. Reusing transducers that have been damaged during reprocessing will potentially negatively affect the acquired images. Echo contrast or flow velocity from these distorted images may provide inaccurate measurement results and misleading diagnoses. Approved: 05/16/2017; Reapproved: 03/25/2018, 11/03/2018, 03/27/2020, 03/05/2021, 12/05/2022. References 1Hangiandreou NJ, Stekel SF, Tradup DJ, et al. Four-year experience with a clinical ultrasound quality control program. Ultrasound Med Biol 2011; 37: 1350– 1357. https://doi.org/10.1016/j.ultrasmedbio.2011.05.007. 2Vachutka J, Dolezal L, Kollmann C, et al. The effect of dead elements on the accuracy of doppler ultrasound measurements. Ultrason Imaging 2014; 19: 3– 13. https://doi.org/10.1177/0161734613508933. 3Phillips WH, Weigang B, Moore GW, et al. The methods and effects of transducer degradation on image quality and the clinical efficacy of diagnostic sonography. J Diag Med Sonography 2003; 19: 3– 13. https://doi.org/10.1177/8756479302239545. 4 Environmental Cleaning and Disinfection Recommendations. 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Governament of Canada website. https://www.healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2004/14289a-eng.php#. Accessed March 24, 2020. 33O'Rourke M, Levan P, Khan T. Current use of ultrasound transmission gel for transesophageal echocardiogram examinations: a survey of cardiothoracic anesthesiology fellowship directors. J Cardiothorac Vasc Anesth 2014; 28: 1208– 1210. https://doi.org/10.1053/j.jvca.2014.02.001. 34Rutala WA, White MS, Gergen MF, Weber DJ. Bacterial contamination of keyboards: efficacy and functional impact of disinfectants. Infect Control Hosp Epidemiol 2006; 27: 372– 377. https://doi.org/10.1086/503340. Early ViewOnline Version of Record before inclusion in an issue FiguresReferencesRelatedInformation

Value-assessment of computer-assisted navigation strategies during percutaneous needle placement

PurposeNavigational strategies create a scenario whereby percutaneous needle-based interventions of the liver can be guided using both pre-interventional 3D imaging datasets and dynamic interventional ultrasound (US). To score how such technologies impact the needle placement process, we performed kinematic analysis on different user groups.MethodsUsing a custom biopsy phantom, three consecutive exercises were performed by both novices and experts (n = 26). The exercise came in three options: (1) US-guidance, (2) US-guidance with pre-interventional image-registration (US + Reg) and (3) US-guidance with pre-interventional image-registration and needle-navigation (US + Reg + Nav). The traveled paths of the needle were digitized in 3D. Using custom software algorithms, kinematic metrics were extracted and related to dexterity, decision making indices to obtain overall performance scores (PS).ResultsKinematic analysis helped quantifying the visual assessment of the needle trajectories. Compared to US-guidance, novices yielded most improvements using Reg (PSavg(US) = 0.43 vs. PSavg(US+Reg) = 0.57 vs. PSavg(US+Reg+Nav) = 0.51). Interestingly, the expert group yielded a reversed trend (PSavg(US) = 0.71 vs PSavg(US+Reg) = 0.58 vs PSavg(US+Reg+Nav) = 0.59).ConclusionDigitizing the movement trajectory allowed us to objectively assess the impact of needle-navigation strategies on percutaneous procedures. In particular, our findings suggest that these advanced technologies have a positive impact on the kinematics derived performance of novices.

Abstract No. 270 Safety and performance of the EPIONE robotic assistance for CT-guided percutaneous needle placement in the abdomen: pre-clinical study in pigs

Abstract No. 270 Safety and performance of the EPIONE robotic assistance for CT-guided percutaneous needle placement in the abdomen: pre-clinical study in pigs

Robotic assistance for percutaneous needle insertion in the kidney: preclinical proof on a swine animal model

BackgroundWe evaluated the accuracy, safety, and feasibility of a computed tomography (CT)-guided robotic assistance system for percutaneous needle placement in the kidney.MethodsFiducials surgically implanted into the kidneys of two pigs were used as targets for subsequent robotically-assisted needle insertion. Robotically-assisted needle insertions and CT acquisitions were coordinated using respiratory monitoring. An initial scan volume data set was used for needle insertion planning defining skin entry and target point. Then, needle insertion was performed according to robot positioning. The accuracy of needle placement was evaluated upon the distance between the needle tip and the predefined target on a post needle insertion scan. A delayed contrast-enhanced CT scan was acquired to assess safety.ResultsEight needle trajectories were performed with a median procedural time measured from turning on the robotic system to post needle insertion CT scan of 21 min (interquartile range 15.5−26.5 min). Blind review of needle placement accuracy was 2.3 ± 1.2 mm (mean ± standard deviation) in lateral deviation, 0.7 ± 1.7 mm in depth deviation, and 2.8 ± 1.3 mm in three-dimensional Euclidian deviation. All needles were inserted on the first attempt, which determined 100% feasibility, without needle readjustment. The angulation and length of the trajectory did not impact on the needle placement accuracy. Two minor procedure-related complications were encountered: 2 subcapsular haematomas (13 × 6 mm and 35 × 6 mm) in the same animal.ConclusionsRobotically-assisted needle insertion was shown feasible, safe and accurate in a swine kidney model. Further larger studies are needed.

CT-Guided Interstitial Low Dose-RATE Brachytherapy for Recurrent Colorectal Cancer

Patients with pelvic or retroperitoneal recurrences of colorectal cancer (CRC) have poor overall survival, with retrospective studies suggesting a possible survival benefit with local therapy. However, many patients present with disease that is either unresectable, or in which resection will result in significant morbidity or margin positivity. We sought to examine the local control, overall survival (OS), and toxicity of minimally invasive CT-guided low dose-rate (LDR) brachytherapy in this setting, for which there is limited published data.This study was a retrospective analysis of all patients at our institution who have undergone CT-guided LDR brachytherapy for recurrent CRC. Patient, tumor, and treatment characteristics were collected, along with physician-reported symptoms in the medical record. Patients underwent dose calculation based on pre-implantation CT imaging and contouring of gross tumor volume (GTV), followed by CT-guided percutaneous interstitial needle placement of either Iodine-125 or Palladium-103 permanent seed implants prescribed to the GTV. Response Evaluation Criteria in Solid Tumors (RECIST) criteria were used to interpret treatment response, and the Kaplan-Meier method was used to estimate rates of overall survival (OS) and in-field control (IFC). IFC was defined as a lack of progression of disease within the pre-implantation defined target volume.Between December 2016 and August 2020, 13 patients underwent 18 CT-guided LDR seed implantations (6 I-125, 12 Pd-103) for pelvic or retroperitoneal recurrences of CRC at our institution, with a median follow-up of 17 months. 17 treatments were for pelvic recurrences, while one treatment was for a retrocaval nodal recurrence. The median prescribed dose to the target volume was 80 Gy (range 40-110 Gy), with a median target volume of 5.0 cc (range 0.6-25.5 cc). The 1-year estimated rates of OS and IFC were 94.4% (CI 84.4-100%) and 82.4% (CI 66.1-100%), respectively. All in-field failures occurred in targets above the median target volume of 5 cc. All patients previously received definitive treatment for either initially locally advanced (8 patients) or limited metastatic disease (5 patients). Of the 18 implantations, four were performed for isolated pelvic recurrences and 13 for either oligo-progressive or oligo-recurrent metastatic disease, with a median of two active sites of disease at the time of seed implantation. One patient received palliative brachytherapy after a poly-metastatic recurrence. No patients experienced grade 2 or higher toxicities. Three patients experienced a grade 1 toxicity (proctitis, pain, and fatigue), and one patient developed an asymptomatic recto-vaginal fistula detected on imaging, which was outside of the brachytherapy field.CT-guided interstitial LDR brachytherapy achieved high rates of control and overall survival with minimal long-term toxicity in patients with pelvic and retroperitoneal recurrences of CRC.

Robotic Assistance System for Cone-Beam Computed Tomography-Guided Percutaneous Needle Placement

PurposeThe study aimed to evaluate a new robotic assistance system (RAS) for needle placement in combination with a multi-axis C-arm angiography system for cone-beam computed tomography (CBCT) in a phantom setting.Materials and MethodsThe RAS consisted of a tool holder, dedicated planning software, and a mobile platform with a lightweight robotic arm to enable image-guided needle placement in conjunction with CBCT imaging. A CBCT scan of the phantom was performed to calibrate the robotic arm in the scan volume and to plan the different needle trajectories. The trajectory data were sent to the robot, which then positioned the tool holder along the trajectory. A 19G needle was then manually inserted into the phantom. During the control CBCT scan, the exact needle position was evaluated and any possible deviation from the target lesion measured.ResultsIn total, 16 needle insertions targeting eight in- and out-of-plane sites were performed. Mean angular deviation from planned trajectory to actual needle trajectory was 1.12°. Mean deviation from target point and actual needle tip position was 2.74 mm, and mean deviation depth from the target lesion to the actual needle tip position was 2.14 mm. Mean time for needle placement was 361 s. Only differences in time required for needle placement between in- and out-of-plane trajectories (337 s vs. 380 s) were statistically significant (p = 0.0214).ConclusionUsing this RAS for image-guided percutaneous needle placement with CBCT was precise and efficient in the phantom setting.

A robotic system for spine surgery positioning and pedicle screw placement.

In recent years, surgeons have explored minimally invasive methods of percutaneous pedicle screw implantation which can effectively reduce human injuries. This article presents an accurate and efficient positioning method and robot system for percutaneous needle placement under c-arm fluoroscopy. A simple five degree of freedom (DOF) robot with a unique end-effector is designed to perform perspective calibration and image space registration. The principle of pedicle standard axis positioning is adopted to make the axis of the pedicle overlap with the x-ray axis of c-arm. Then the clinical operation is carried out to verify the clinical feasibility of the designed robot and positioning method. The experimental results show that a total of 26 pedicle screws were accurately implanted. The accuracy of Grade A is 96.15%. The positioning time of a single guide pin is about 154.77s, and three x-ray films need to be taken on average. The positioning accuracy is increased by using the present method. In addition, this method is simple in operation, short in operation time, low in X-ray exposure.

Feasibility, safety and accuracy of a CT-guided robotic assistance for percutaneous needle placement in a swine liver model

Evaluate the feasibility, safety and accuracy of a CT-guided robotic assistance for percutaneous needle placement in the liver. Sixty-six fiducials were surgically inserted into the liver of ten swine and used as targets for needle insertions. All CT-scan acquisitions and robotically-assisted needle insertions were coordinated with breath motion using respiratory monitoring. Skin entry and target points were defined on planning CT-scan. Then, robotically-assisted insertions of 17G needles were performed either by experienced interventional radiologists or by a novice. Post-needle insertion CT-scans were acquired to assess accuracy (3D deviation, ie. distance from needle tip to predefined target) and safety. All needle insertions (43/43; median trajectory length = 83 mm (interquartile range [IQR] 72–105 mm) could be performed in one (n = 36) or two (n = 7) attempts (100% feasibility). Blinded evaluation showed an accuracy of 3.5 ± 1.3 mm. Accuracy did not differ between novice and experienced operators (3.7 ± 1.3 versus 3.4 ± 1.2 mm, P = 0.44). Neither trajectory angulation nor trajectory length significantly impacted accuracy. No complications were encountered. Needle insertion using the robotic device was shown feasible, safe and accurate in a swine liver model. Accuracy was influenced neither by the trajectory length nor by trajectory angulations nor by operator’s experience. A prospective human clinical trial is recruiting.

Multicenter Study to Evaluate a New Robotic Device for Image-guided Percutaneous Needle Placement

Multicenter Study to Evaluate a New Robotic Device for Image-guided Percutaneous Needle Placement

The Source and the Course of the Articular Branches to the T4-T8 Zygapophysial Joints

To define the source and the course of the articular branches to the midthoracic zygapophysial ("z") joints. Cadaveric dissection. The Gross Anatomy Laboratory of the Duke University School of Medicine. Ten human cadaveric thoraces. Gross and stereoscopic dissection of dorsal rami T4-T8 was performed bilaterally on 10 adult embalmed cadavers. The medial and lateral branches were traced to their origins from the dorsal rami, and the course of the articular nerves was documented through digital photography. Radio-opaque wire (20 gauge) was applied to the nerves. Fluoroscopic images were obtained to delineate their radiographic course with respect to osseous landmarks. Forty-eight inferior articular branches were identified. Three (6.3%) originated from the medial branch and 44 (91.7%) from the dorsal ramus. One was indeterminate. Fifty-one superior articular branches were identified. Eight (15.7%) originated from the medial branch and 43 (84.3%) from the dorsal ramus. In 12% of cases (6/50), there was side-to-side asymmetry in the origins of the articular branches. Nerves were commonly suspended in the intertransverse space. The articular branches contacted an osseous structure in only 39% of cases. As previously reported, a "descending branch" was not identified in any specimen. Articular branches to the T4-T8 z-joints have substantial inter- and intraspecimen variability of origin. They typically arise from the dorsal ramus rather than the medial branch and frequently do not contact any osseous structure to allow percutaneous needle placement.

A targeting method for robot-assisted percutaneous needle placement under fluoroscopy guidance.

Minimally invasive procedures are rapidly growing in popularity thanks to advancements in medical robots, visual navigation and space registration techniques. This paper presents a precise and efficient targeting method for robot-assisted percutaneous needle placement under C-arm fluoroscopy. A special end-effector was constructed to perform fluoroscopy calibration and robot to image-space registration simultaneously and automatically. In addition, formulations were given to compute the movement of robot targeting and evaluate targeting accuracy using only one X-ray image. A pre-clinical experiment showed that the maximum angle error was 0.94° and the maximum position error of a target located 80 mm below the end-effector was 1.31 mm. And evaluation of the system in a robot-assisted pedicle screws placement surgery has justified the accuracy and reliability of proposed method in clinical applications. The positioning accuracy was increased by using present method. Moreover, radiation exposure and operation time were reduced significantly compared to other commonly used methods.

A targeting method for robot-assisted percutaneous needle placement under fluoroscopy guidance

Minimally invasive procedures are rapidly growing in popularity thanks to advancements in medical robots, visual navigation and space registration techniques. This paper presents a precise and efficient targeting method for robot-assisted percutaneous needle placement under C-arm fluoroscopy. In this method, a special end-effector was constructed to perform fluoroscopy calibration and robot to image-space registration simultaneously. In addition, formulations were given to compute the movement of robot targeting and evaluate targeting accuracy using only one X-ray image. With these techniques, radiation exposure and operation time were reduced significantly compared to other commonly used methods. A pre-clinical experiment showed that the maximum angle error was 0.94° and the maximum position error of a target located 80mm below the end-effector was 1.31mm. And evaluation of the system in a robot-assisted pedicle screws placement surgery has justified the accuracy and reliability of proposed method in clinical applications.

Using Navi-Robot and a CT Scanner to Guide Biopsy Needles

Purpose of this study was to control the suitability of Navi-Robot, a robotic system developed by our research group, to guide percutaneous needle placement under computed tomography (CT) in order to achieve lower radiation exposure and a shorter procedure. The system consists of a high precision six-degrees-of-freedom self-balanced arm, able to move both in passive and active modes, which allows the physician an accurate needle-insertion. The target and the needle entry points are selected by the surgeon on a desktop computer, that acquires DICOM images from the CT scan, and that, using software developed for this purpose, detects also the position of at least three radio opaque markers placed on the patient or on the stretcher. Once these data are obtained, a new system of reference is established based on the markers position, obtaining the coordinates of target and entry point in the new frame of reference. Going then to touch the tip of the spheres with the tip of the robot end effector in passive mode, and recording their position, the robot learns where the two points of interest are located in its frame of reference. A first test was performed on a Plexiglas board; the accuracy achieved was measured as the distance between the needle tip and the target. The results of the in vitro experiment showed that the system is able to reach the target with an accuracy of 1.2 mm.

Mini access guide to simplify calyceal access during percutaneous nephrolithotomy: A novel device.

Introduction:A precise puncture of the renal collecting system is the most essential step for percutaneous nephrolithotomy (PCNL). There are many techniques describing this crucial first step in PCNL including the bull's eye technique, triangulation technique, free-hand technique, and gradual descensus technique. We describe a novel puncture guide to assist accurate percutaneous needle placement during bull's eye technique.Methods:The mini access guide (MAG) stabilizes the initial puncture needle by mounting it on an adjustable multidirectional carrier fixed to the patient's skin, which aids in achieving the “bull's eye” puncture. It also avoids a direct fluoroscopic exposure of the urologist's hand during the puncture. Sixty consecutive patients with solitary renal calculus were randomized to traditional hand versus MAG puncture during bull's eye technique of puncture and the fluoroscopy time was assessed.Results:The median fluoroscopy screening time for traditional free-hand bull's eye and MAG-guided bull's eye puncture (fluoroscopic screening time for puncture) was 55 versus 21 s (P = 0.001) and the median time to puncture was 80 versus 55 s (P = 0.052), respectively. Novice residents also learned puncture technique faster with MAG on simulator.Conclusion:The MAG is a simple, portable, cheap, and novel assistant to achieve successful PCNL puncture. It would be of great help for novices to establish access during their learning phase of PCNL. It would also be an asset toward significantly decreasing the radiation dose during PCNL access.

Using an abdominal phantom to teach urology residentes ultrasound-guided percutaneous needle placement.

ABSTRACTIntroduction:To assess the effect of a hands-on ultrasound training session to teach urologic trainees ultrasound-guided percutaneous needle placement.Materials and methods:University of California, San Francisco (UCSF) urology residents completed a time trial, placing a needle into a phantom model target under ultrasound guidance. Participants were randomized into three educational exposure groups: Group 1's time trial occurred prior to any teaching intervention, group 2's after experiencing a hands-on training module, and group 3's after exposure to both the training module and one-on-one attending feedback. Needle placement speed and accuracy as well as trainees' perceived confidence in utilizing ultrasound were measured.Results:The study cohort consisted of 15 resident trainees. Seven were randomized to group 1, three to group 2, and five to group 3. All residents reported minimal prior ultrasound experience. Their confidence in using ultrasound improved significantly after completing the training module with the most significant improvement seen among junior residents. Time to needle placement was fastest after receiving attending feedback (46.6sec in group 3 vs. 82.7sec in groups 1 and 2, p<0.01). Accuracy also improved with attending feedback, though the number of repositioning attempts did not differ significantly between groups.Conclusions:A hands-on training module and use of an abdominal phantom trainer increased resident confidence and skill in their use of ultrasound to guide percutaneous needle positioning. Attending feedback is critical for improving accuracy in needle guidance toward a target. Ultrasound-guided needle positioning is a teachable skill and can be applicable to multiple urologic procedures.

Transillumination for needle localization in the larynx

Transillumination through laryngeal soft tissue may be used to direct percutaneous transcricothyroid membrane subepithelial needle placement in the larynx. Cadaver simulation (canine and human). Lighted devices, including sialendoscopes and fiberoptic cables, were tested as transilluminating obturators in trocars and needles through multiple studies to identify appropriate illumination, monitoring, and equipment for successful localization of needle/trocar tips placed within laryngeal tissue. Lighted 250-micron fiberoptic cables within 23-gauge needles were successfully placed percutaneously through the cricothyroid membrane and maneuvered submucosally into Reinke's space, the midlateral vocal fold, and through the thyroarytenoid gap with monitoring via flexible transnasal laryngoscopy. Technical adaptations in the course of study permitted successful simulation of clinical use in full cadaver study for accurate injection laryngoplasty, confirmed by laryngeal dissection following collagen injection. Small caliber fiberoptic cables are useful as transilluminating obturators to accurately direct needle position within laryngeal tissue. Clinical application of this new technique is anticipated to improve the accuracy of percutaneous needle localization in the larynx, as well as to assist in directed instrumentation of the larynx from an external approach. N/A.

PD4-06 A RANDOMIZED CONTROL TRIAL DEMONSTRATES THAT ULTRASOUND-GUIDED PERCUTANEOUS RENAL ACCESS IS A TEACHABLE SKILL.

You have accessJournal of UrologyImaging/Radiology: Uroradiology I1 Apr 2015PD4-06 A RANDOMIZED CONTROL TRIAL DEMONSTRATES THAT ULTRASOUND-GUIDED PERCUTANEOUS RENAL ACCESS IS A TEACHABLE SKILL. Pauline Filippou, Anobel Odisho, Krishna Ramaswamy, Weiguo Hu, Jianxing Li, and Thomas Chi Pauline FilippouPauline Filippou More articles by this author , Anobel OdishoAnobel Odisho More articles by this author , Krishna RamaswamyKrishna Ramaswamy More articles by this author , Weiguo HuWeiguo Hu More articles by this author , Jianxing LiJianxing Li More articles by this author , and Thomas ChiThomas Chi More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.318AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Ultrasound (US)-guided percutaneous renal access minimizes radiation exposure, but is not widely performed by urologists in the United States. Urologic trainees acquire varying amounts of US experience. This randomized control trial evaluates the effect of a hands-on US training session on US-guided percutaneous needle placement accuracy. METHODS PGY1-6 trainees of the UCSF urology residency program were randomized intro three groups. All groups completed a time trial of placing a needle into a modeled target under US guidance. Group 1's time trial occurred prior to any training, group 2's after experiencing a hands-on training module, and group 3's after exposure to both the training module and 1-on-1 attending feedback. Time until needle placement, number of repositioning attempts and needle placement accuracy were measured. A confidence survey was taken before and after module exposure. Statistical analyses were performed using Student's t tests. RESULTS Seven trainees were randomized to group 1, three to group 2 and five to group 3. All residents reported minimal prior US training. Overall confidence scores (scale: 1–40; 40 most confident) improved significantly after completing the training module (16.8 before vs. 25.1 after, p<0.01). This improvement was most significant in PGY1-3 residents (12.1 vs. 21.1, p<0.01). Time to needle placement was fastest and most accurate after attending feedback in group 3 (46.6 sec in group 1 vs. 82.4 sec in groups 2 and 3, p<0.01; 80% accuracy in group 1 vs 38% accuracy in groups 2 and 3, p<0.01). Number of repositioning attempts did not differ significantly between the three groups. CONCLUSIONS Hands-on training modules increased resident confidence in their use of US-guided needle placement for percutaneous renal access. However, attending teaching and feedback is critical for improving accuracy in guiding a needle toward its intended target. Short, formalized training sessions in US use can be readily implemented in urologic training to improve resident skill and confidence. US-guided percutaneous renal access is a teachable, achievable skill. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e88-e89 Peer Review Report Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Pauline Filippou More articles by this author Anobel Odisho More articles by this author Krishna Ramaswamy More articles by this author Weiguo Hu More articles by this author Jianxing Li More articles by this author Thomas Chi More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

An overview of systems for CT- and MRI-guided percutaneous needle placement in the thorax and abdomen.

Minimally invasive biopsies, drainages and therapies in the soft tissue organs of the thorax and abdomen are typically performed through a needle, which is inserted percutaneously to reach the target area. The conventional workflow for needle placement employs an iterative freehand technique. This article provides an overview of needle-placement systems developed to improve this method. An overview of systems for needle placement was assembled, including those found in scientific publications and patents, as well as those that are commercially available. The systems are categorized by function and tabulated. Over 40 systems were identified, ranging from simple passive aids to fully actuated robots. The overview shows a wide variety of developed systems with growing complexity. However, given that only a few systems have reached commercial availability, it is clear that the technical community is struggling to develop solutions that are adopted clinically. Copyright © 2014 John Wiley & Sons, Ltd.

Real-time ultrasound-guided needle injection of the mouse jugular vein.

This unit describes a novel method for direct venous injection into mice that offers potentially significant advantages over commonly used mouse vein injection techniques. This is achieved via percutaneous needle placement into the mouse jugular vein under real-time B-mode ultrasound (US) imaging. Real-time US imaging of the injection process allows for immediate determination of the overall success of injection. Unique, and potentially significant, advantages of this technique over others include: (1) direct visual confirmation of needle tip placement in the lumen of the vein, (2) immediate visual detection of extravascular extravasation of injectate, when compared to blinded techniques, such as tail vein injections, and (3) reduced morbidity and mortality compared to surgical vascular access techniques (i.e., jugular vein cannulation). This technique may lead to more accurate determination of the success of the injection procedure for each mouse, thus improving the quality of acquired data in dependent mouse experiments.