Tip Placement Research Articles

Long-Term Outcomes of Patients with Stent Tips Embedded into Internal Carotid Artery Branches during Aneurysm Coiling.

During stent-assisted coiling of ICA aneurysms, stent tips are sometimes unintentionally embedded into ICA branches. Stent tips can be visualized because they have radiopaque markers. Concerns regarding stent tip misplacement include risks of artery perforation and occlusion. The aim of this study was to evaluate the long-term outcomes of ICA branches with embedded stent tips. ICA branches with embedded stent tips were identified among 35 patients with unruptured ICA aneurysms treated with stent-assisted coiling between November 2003 and November 2014. Patient clinical and angiographic outcomes associated with the embedded stent tip were analyzed. Most of the 35 studied aneurysms were paraclinoid ICA aneurysms (n = 30). The most commonly involved ICA branch was the posterior communicating artery (26 patients, 74.3%), followed by the anterior choroidal artery (8 patients, 22.9%) and ophthalmic artery (1 patient, 2.9%). During the follow-up period (38.6 ± 17.9 months), no new neurologic deficits developed. Neither hemorrhagic nor thromboembolic events occurred. Angiography was performed during the final follow-up evaluation at a mean of 32.7 ± 18.0 months, and all ICA branches with embedded stent tips showed patent blood flow without severe luminal narrowing. In our experience, placement of a stent tip into ICA branches during stent-assisted coiling was not associated with any major adverse events.

Electrocardiography-controlled central venous catheter tip positioning in patients with atrial fibrillation.

A significant increase of the p-wave of a real-time intracavitary electrocardiography is a reliable and safe method to confirm the central venous catheter tip position close to the atrium. However, conflicting data about the feasibility of electrocardiography exist in patients with atrial fibrillation. An observational prospective case-control cohort study was set up to study the feasibility and accuracy of the electrocardiography-controlled central venous catheter tip placement in 13 patients with atrial fibrillation versus 10 patients with sinus rhythm scheduled for elective surgery. Each intervention was crosschecked with ultrasound-guided positioning via right supraclavicular fossa view and chest radiography. Ultrasound-guided supraclavicular venipuncture of the right subclavian vein and guidewire advancement were performed. A B-mode view of the superior vena cava and the right pulmonary artery was obtained to visualize the J-tip of the guidewire. The central venous catheter was advanced over the guidewire and the electrocardiography was derived from the J-tip of the guidewire protruding from the central venous catheter tip. Electrocardiography was read for increased p- and atrial fibrillation waves, respectively, and insertion depth was compared with the ultrasound method. Electrocardiography indicated significantly increasing fibrillation and p-waves, respectively, in all patients and ultrasound-guided central venous catheter positioning confirmed a tip position within the lower third of the superior vena cava. Electrocardiography-guided central venous catheter tip positioning is a feasible real-time method for patients with atrial fibrillation. Combined with ultrasound, the electrocardiography-controlled central venous catheter placement may eliminate the need for postinterventional radiation exposure.

Research progress in electrocardiogram-guided peripherally inserted central catheter placement and tip position

As a new guidance in central venous access device tip placement, electrocardiogram has been widely used in intravenous infusion therapy, reportedly with sound outcome. We wrote this review to help clinical nurses understand and use this approach. Key words: Peripherally inserted central catheter; Electrocardiogram

Microelectrode accuracy in deep brain stimulation surgery

Microelectrode recording (MER) provides vital neurophysiological information about target nuclei during deep brain stimulation (DBS). There have been extensive studies looking at the accuracy of DBS lead placement; however, to date, no large series have assessed the accuracy of the microelectrode. In this study, we report the accuracy of microelectrode tip placement in comparison to preoperatively planned radiographic target. Patients who underwent DBS with MER from 2014 to 2016 were included in the study. At the authors’ institution, intra-operative CT (iCT) is routinely performed after the first microelectrode track to confirm tip accuracy. Retrospective analysis of microelectrode track error was calculated between the planned trajectory and the microelectrode tip. The radial error was calculated on the same axial plane using the Euclidian distance formula, and multivariate analysis was performed to ascertain any directional bias of error. A total of 227 microelectrode tracks were analyzed, (150 STN, 50 ViM, 27 GPi) yielding a total radial error of 1.2 mm ± 0.2 SEM across all targets. Analysis of vector error distribution revealed lack of directional bias. MER is an accurate electrophysiological representation of the planned target.

Kalman filter-based EM-optical sensor fusion for needle deflection estimation.

In many clinical procedures such as cryoablation that involves needle insertion, accurate placement of the needle's tip at the desired target is the major issue for optimizing the treatment and minimizing damage to the neighboring anatomy. However, due to the interaction force between the needle and tissue, considerable error in intraoperative tracking of the needle tip can be observed as needle deflects. In this paper, measurements data from an optical sensor at the needle base and a magnetic resonance (MR) gradient field-driven electromagnetic (EM) sensor placed 10cm from the needle tip are used within a model-integrated Kalman filter-based sensor fusion scheme. Bending model-based estimations and EM-based direct estimation are used as the measurement vectors in the Kalman filter, thus establishing an online estimation approach. Static tip bending experiments show that the fusion method can reduce the mean error of the tip position estimation from 29.23mm of the optical sensor-based approach to 3.15mm of the fusion-based approach and from 39.96 to 6.90mm, at the MRI isocenter and the MRI entrance, respectively. This work established a novel sensor fusion scheme that incorporates model information, which enables real-time tracking of needle deflection with MRI compatibility, in a free-hand operating setup.

Placement of Stimulating Epidural Catheter for a Patient With Large Scapular Sarcoma: A Case Report.

We report the use of continuous electrical stimulation to assist with the preoperative placement of a thoracic epidural which was used to provide postoperative analgesia in a patient undergoing excision of a large scapular sarcoma. The size of the sarcoma and the surrounding area required to maintain a sterile surgical field necessitated that the epidural catheter be inserted several vertebral interspaces caudal to the level of desired catheter tip termination. The use of electrical stimulation allowed for sequential intercostal muscle stimulation during threading, which enabled the placement of the catheter tip at the appropriate spinal level to optimize analgesia.

A Proposed Simple and Accurate Technique for Optimal Long-Term Hemodialysis Catheter Tip Placement.

We describe a simple ultrasound (US)-guided technique for accurate anatomical right atrium localization prior to permanent hemodialysis catheter insertion. It is used in patients for whom a permanent hemodialysis catheter will be inserted through an internal jugular vein access, in order to have the functional catheter tip located at the mid-level of the right atrium. In this technique, the right atrium is localized on US via left intercostal approach prior to catheter insertion under fluoroscopic guidance.

Electrocardiogram-guided Technique: An Alternative Method for Confirming Central Venous Catheter Tip Placement.

Background:The current standard followed for assessing central venous catheter (CVC) tip placement location is through radiological confirmation using chest X-ray (CXR). Placement of CVCs under electrocardiogram (ECG) guidance may save cost and time compared to CXR.Objective:The objective of this study is to compare the accurate placement of the CVC tip using anatomical landmark technique with ECG-guided technique. Another objective is to compare CVC placement time and postprocedural complications between the two techniques.Methods and Materials:A total of 144 adult individuals, who were critically ill and required CVC placement in the Emergency Department, were included for the study. Study duration was 6 months. Anatomical landmark and ECG-guided groups were assigned 72 participants each. Analyses were performed using t and Chi square-tests.Results:It was observed that 13 (18%) in the landmark technique were malpositioned as compared to none in the ECG-guided technique (P = 0.000). The landmark group had 22 (30.6%) participants with arrhythmias during the procedure, compared to none in the ECG-guided group (P = 0.000). The landmark group revealed that 30 (41.7%) of the CVC were overinserted and required immediate repositioning, compared to none in the ECG-guided group (P = 0.000).Conclusion:ECG-guided technique was found to be more accurate for CVC tip placement than the anatomical landmark technique. Furthermore, the ECG-guided technique was more time-effective and had less complications than the anatomical landmark technique. Hence, ECG-guided CVC placement is relatively accurate, efficient, and safe and can be considered as an alternative method to conventional radiography for confirmation of CVC tip placement.

Evaluation of a central venous catheter tip placement for superior vena cava-subclavian central venous catheterization using a premeasured length: A retrospective study.

Subclavian central venous catheterization is a common procedure for which misplacement of the central venous catheter (CVC) is a frequent complication that can potentially be fatal. The carina is located in the mid-zone of the superior vena cava (SVC) and is considered a reliable landmark for CVC placement in chest radiographs. The C-length, defined as the distance from the edge of the right transverse process of the first thoracic spine to the carina, can be measured in posteroanterior chest radiographs using a picture archiving and communication system. To evaluate the placement of the tip of the CVC in subclavian central venous catheterizations using the C-length, we reviewed the medical records and chest radiographs of 122 adult patients in whom CVC catheterization was performed (from January 2012 to December 2014) via the right subclavian vein using the C-length. The tips of all subclavian CVCs were placed in the SVC using the C-length. No subclavian CVC entered the right atrium. Tip placement was not affected by demographic characteristics such as age, sex, height, weight, and body mass index. The evidence indicates that the C-length on chest radiographs can be used to determine the available insertion length and place the right subclavian CVC tip into the SVC.

Comparing the conventional 15 cm and the C-length approaches for central venous catheter placement.

Introduction: The present guidelines recommend placing the catheter tip in the superior vena cava (SVC) above the pericardial cephalic reflection. The aim of this study was to compare the accuracy of two different approaches in locating the tip of the Central venous catheter (CVC) at the suggested vascular zone. Methods: This was an interventional study on two hundred patients undergoing Coronary artery bypass surgery (CABG) operation who required a central venous cannulation. They were randomly assigned into two groups. In the first group catheter placement was applied through using the conventional 15 cm method. In the second group a C-length method was applied for measuring the depth of catheter tip placement from the preoperative chest radiographs. For statistical analysis Chi-square test and T-test were used. Results: In the first group (15 cm) 100% of the patients had their catheters placed below the C-line (Carina line) and the average distance between the catheter tip and the C-line was +4.22±2.10 cm. In the second (C-Length) group 52% of the catheters were below C-line with an average distance of +0.77±0.5 cm. There was a meaningful difference between the two groups in respect to the catheter location depth and zone of placement (P<0.001). Conclusion: The C-Length approach in comparison to the conventional 15 cm approach resulted in a considerable higher number of catheters above the recommended C-line, thus it can provide a more reliable and safe mode for CVC placement in the SVC.

Comparison of epidural catheter tip placement between median and paramedian techniques with fluoroscopy

Comparison of epidural catheter tip placement between median and paramedian techniques with fluoroscopy

A randomized controlled study of bedside electrocardiograph-guided tip location technique & the traditional chest radiography tip location technique for peripherally inserted central venous catheter in cancer patients.

Background & objectives:The peripherally inserted central catheter (PICC) has the advantages of higher safety, lower infection rate and longer retention time than peripherally inserted catheter. This study was aimed to evaluate the accuracy and safety of bedside electrocardiograph (ECG)-guided tip location technique in PICC in cancer patients, and compared with traditional chest radiography tip location technique.Methods:Patients were randomly assigned into two groups: The ECG test group patients underwent PICC insertion with ECG-guided tip location, while the control group patients had PICC insertion by the conventional method. The precision of tip location was verified by chest radiography in both groups. The groups were compared with regard to the accuracy of tip placement, anxiety levels before and after the procedure; medical cost and incidence of complications at one week, three months and six months after PICC insertion.Results:Accurate tip location was achieved in 99.30 per cent in the ECG test group vs 92.30 per cent in the control group (P <0.001). At 24 h after the procedure, the anxiety level was significantly lower in the ECG test group. The presence of thrombogenesis was significantly lower in the ECG test group at both three months and six months after the procedure (P=0.04 and P=0.03, respectively).Interpretation & conclusions:The ECG-guided PICC tip location technique was accurate and caused fewer procedure-related complications and less anxiety in patients compared to chest radiography tip location technique. Radiographic confirmation of PICC tip position may not be needed when ECG guidance is used and thus it can help avoid radiation exposure.

Three-dimensionally printed personalized guide plate for percutaneous radiofrequency thermal coagulation in idiopathic trigeminal neuralgia

Radiofrequency thermocoagulation (RFT) is used widely for the treatment of idiopathic trigeminal neuralgia (TN). Precise puncture and placement of the electrode needle tip are crucial for successful RFT. This technical note introduces a novel method for performing RFT using a customized, three-dimensionally (3D)-printed guide plate. Eleven patients with idiopathic TN were treated using this method between February and July 2016. Three had V2 branch TN and eight had V3 branch TN. Punctures in eight patients were successful at the first attempt; slight adjustments were required subsequently in the other three patients. The puncture time in all cases was less than 1min. The patients reported pain relief immediately after RFT, and no complications were observed in any patient. Thus, the customized 3D-printed guide plate offers the advantages of precise placement of the puncture needle and minimal complications.

The view through the ventricle catheter – The new ShuntScope for the therapy of pediatric hydrocephalus

PurposeCorrect placement of the ventricle catheter directly influences the function of cerebral shunt systems. The incidence of proximal catheter misplacement reaches up to 45%. To avoid misplacements and revisions a new intra-catheter endoscope for precise ventricle catheter placement in children was evaluated. MethodsThe semi-rigid ShuntScope (Karl Storz GmbH & Co.KG, Tuttlingen, Germany) with an outer diameter of 1.0 mm and an image resolution of 10,000 pixels was used in a series of 27 children and adolescents (18 males, 9 females, age range 2 months–18 years). Indications included catheter placement in aqueductal stenting (n = 4), first time shunt placement (n = 5), burr hole reservoir insertion (n = 4), catheter placement after endoscopic procedures (n = 7) and revision surgery of the ventricle catheter (n = 7). ResultsShuntScope guided precise catheter placement was achieved in 26 of 27 patients. In one case of aqueductal stenting, the procedure had to be abandoned. One single wound healing problem was noted as a complications. Intraventricular image quality was always sufficient to recognize the anatomical structures. In case of catheter removal, it was helpful to identify adherent vessels or membranes. Penetration of small adhesions or thin membranes was feasible. Postoperative imaging studies demonstrated catheter tip placements analogous to the intraoperative findings. ConclusionsMisplacements of shunt catheters are completely avoidable with the presented intra-catheter technique including slit ventricles or even aqueductal stenting. Potential complications can be avoided during revision surgery. The implementation of the ShuntScope is recommended in pediatric neurosurgery.

Effect of tumescent anesthesia and patient positioning on laser tip junctional distance during endovenous laser ablation.

The correct positioning of the laser tip at the saphenofemoral or saphenopopliteal junction during endovenous laser therapy is paramount to ensure a safe and effective procedure. The aim of this study was to demonstrate how patient positioning and tumescence infiltration can affect this safe junctional distance. A retrospective review of a prospectively maintained database was carried out for all patients who received endovenous laser treatment for symptomatic varicose veins between February 2008 and February 2014 in one surgeon's practice in a teaching hospital vascular unit. The junctional distance of the laser tip from the saphenofemoral or saphenopopliteal junction was measured two times during the procedure: before tumescence and before laser deployment with the patient in a Trendelenburg position. Junctional distance was found to have increased in 62% cases (490 patients; great saphenous vein [GSV], 348; small saphenous vein [SSV], 142). Of these, 17% (84) required the laser tip to be advanced (GSV, 56; SSV, 28) to maintain a desired junctional distance of 0.75 to 2cm. In 185 patients (23%), the junctional distance was noted to have been reduced (GSV, 155; SSV, 30), with 58% (GSV, 79; SSV, 28) requiring the laser tip to be withdrawn to the desired junctional distance; 23% of patients (185) had no change in the junctional distance. This study has demonstrated the effect of tumescence infiltration and Trendelenburg positioning on laser tip placement, and thus a final junctional measurement before activation of the laser is recommended to maintain a safe and optimal junctional distance.

Sensitivity of aspiration as a safety test before injection of soft tissue fillers.

Embolism due to accidental intra-arterial injection of a soft tissue filler (STF) can lead to serious complications. Physicians practice aspiration as a safety test before injection to rule out intra-arterial placement of the needle tip. The value of aspiration as a safety test is evaluated in this study, which also considered the rheological properties of different STFs and their needle dimensions. Aspiration with eleven different needle sizes and 24 different STFs was performed using Ringer's lactate (RL) colored with blue skin marking ink and secondly an empty saline bag containing anticoagulated blood, both pressurized to 150mmHg to mimic arterial blood pressure. Time between the start of aspiration and liquid in the needle hub was recorded. A total of 340 individual aspiration tests with different STFs and needles were performed, of which 112 yielded true-positive results within 1-s and 128 yielded false-negative results after 10s. Positive results between one and ten seconds were seen in 101 aspiration tests. True-positive results were seen in 33% of the tests performed with STFs within 1s of aspiration. Aspiration test results are influenced by needle diameter, needle length, and rheological properties of STFs. Additional safety measures are necessary to further reduce risk of inadvertent intravascular injection of STFs.

Effectiveness of Intracavitary Electrocardiogram Guidance in Peripherally Inserted Central Catheter Tip Placement in Neonates.

Correct tip location is crucial for a peripherally inserted central catheter (PICC) to maximize the effects of central venous infusion. However, it is difficult to place the tip in a correct location in neonates because of the unreliable estimated length by surface landmark. Therefore, we evaluated the feasibility and safety of an improved intracavitary electrocardiogram (IC-ECG) technique in guiding PICC placement in neonates based on the ratios of P/R wave amplitudes on IC-ECG. The results showed that all of the 32 neonates whose PICCs had been successfully placed and correct tip position verified by chest radiography acquired qualified P wave on IC-ECG. The average ratio of P/R wave amplitude was 0.6 ± 0.1, with a range of 0.4 to 0.8. The 49 neonates who received IC-ECG-guided PICC catheterization showed higher success rates of correct PICC tip position on the first attempt than traditional, predetermined length estimation on surface landmark (93.9% vs 62.5%, χ = 18.01, P < .001). No significant complications occurred in the studied neonates. Based on these findings, IC-ECG-guided tip placement appears to be a promising approach in improving the success rate of tip location when placing a PICC in neonates.

Single-Operator Ultrasound-Guided Central Venous Catheter Insertion Verifies Proper Tip Placement.

To evaluate whether a single-operator ultrasound-guided, right-sided, central venous catheter insertion verifies proper placement and shortens time to catheter utilization. Prospective observational study with historical controls. Adult ICUs. Sixty-four consecutive patients undergoing ultrasound-assisted right-sided central venous catheterization compared with 92 serial historic controls who had unassisted central catheter insertion at the same sites. Subcostal transthoracic echocardiography during catheter insertion. The primary outcome was the correct placement of the catheter tip determined by postprocedural chest radiography. The subclavian site was used in 41 patients (64%) (inserted without ultrasound guidance) in the ultrasound-assisted group and 62 (67%) in the control group, whereas the jugular vein was used in the remaining patients. The tip was accurately positioned in 59 of 68 patients (86.7%) in the ultrasound-assisted group compared with 51 of 94 (54.8%) in the control group (p < 0.001). The median time from end of the procedure to catheter utilization after chest radiography approval was 2.4 hours. A single-operator ultrasound-guided central venous catheter insertion is effective in verifying proper tip placement and shortens time to catheter utilization.

Rhinoplasty Refinements: The Role of the Open Approach.

The open rhinoplasty technique facilitates accurate visualization of deformities and aesthetic disharmonies in addition to visualization for precise correction. Through a series of videos, this case represents the evolution of the open rhinoplasty technique, demonstrating a wide range in complexity of maneuvers to achieve the desired correction in rhinoplasty. The video demonstrates reduction of the nasal dorsum by way of a component dorsal reduction, reconstitution of the cartilaginous midvault, and suture techniques for reshaping the nasal tip. Nasal tip deprojection and placement of alar contour grafts are also demonstrated in this case. The aim is to provide the rhinoplasty surgeon with examples of basic and sophisticated techniques and also to demonstrate the minutia and nuance of open rhinoplasty.

Effectiveness of Intracavitary Electrocardiogram Guidance in Peripherally Inserted Central Catheter Tip Placement in Neonates.

Effectiveness of Intracavitary Electrocardiogram Guidance in Peripherally Inserted Central Catheter Tip Placement in Neonates.