Thyroid US-guided FNA techniques: A prospective,randomized controlled study.

BACKGROUND: Thyroid nodules are common in the general population. Ultrasonography is the most efficient diagnostic approach to evaluate thyroid nodules. The US FNAC procedure can be performed using either the short axis (perpendicular), or a long axis (parallel) approach to visualize the needle as it is advanced toward the desired nodule. The main aim of this study was to compare the percentage of non-diagnostic results between the long and short axis approach. METHODS: A prospective study that included a randomized controlled trial and was divided into two arms-the short axis and the long axis-was conducted. A total of 245 thyroid nodules were collected through the fine needle aspiration cytology, performed with ultrasound, from march 2021 to march 2022. The patient's demographic information were collected and also nodules characteristics. RESULTS: Of 245 nodules sampled, 122 were sampled with the long axis method, while 123 with the short axis method. There is not significantly less non diagnostic approach with either method compared to the other (11.5 % vs 16.3 % respectively). DISCUSSION: Previous studies came to the conclusion that the long axis method yields fewer non diagnostic samples. This study evaluated the two FNA approaches which were proceeded by the same physician who is expert in both techniques. CONCLUSION: The US FNAC performed in the long axis approach will not produce more conclusive results and less non diagnostic results (Bethesda category 1) than the short axis approach one.

Creation of High-Quality Deep-Blue AIE Emitter with a Crossed Long-Short Axis Structure for Efficient and Versatile OLEDs.

Developing deep-blue emitters for organic light-emitting diodes (OLEDs) is critical but challenging, which requires a good balance between light color, exciton utilization, and photoluminescence quantum yield (PLQY) of solid film. Herein, a high-quality deep-blue emitter, abbreviated 2TriPE-CzMCN, is designed by introducing an aggregation-induced emission (AIE) group into a crossed long-short axis (CLSA) skeleton. Theoretical and experimental investigations reveal that the CLSA molecular design can achieve a balance between deep-blue emission and triplet-excitons utilization, while the high PLQY of the solid film resulting from the AIE feature helps to improve the performance of OLEDs. Consequently, when 2TriPE-CzMCN is used as the emitting dopant, the OLED exhibits a deep-blue emission at 430 nm with a record-high maximum external quantum efficiency (EQE) of 8.84%. When 2TriPE-CzMCN serves as the host material, the sensitized monochrome orange and two-color white OLEDs (WOLEDs) realize high EL performances that exceed the efficiency limit of conventional fluorescent OLEDs. Moreover, high-performance three-color WOLEDs with a color rendering index (CRI) exceeding 90 and EQE up to 18.08% are achieved by using 2TriPE-CzMCN as the blue-emitting source. This work demonstrates that endowing CLSA molecule with AIE feature is an effective strategy for developing high-quality deep-blue emitters, and high-performance versatile OLEDs can be realized through rational device engineering.

Short-axis PET image quality improvement based on a uEXPLORER total-body PET system through deep learning.

PURPOSE: The axial field of view (AFOV) of a positron emission tomography (PET) scanner greatly affects the quality of PET images. Although a total-body PET scanner (uEXPLORER) with a large AFOV is more sensitive, it is more expensive and difficult to widely use. Therefore, we attempt to utilize high-quality images generated by uEXPLORER to optimize the quality of images from short-axis PET scanners through deep learning technology while controlling costs. METHODS: The experiments were conducted using PET images of three anatomical locations (brain, lung, and abdomen) from 335 patients. To simulate PET images from different axes, two protocols were used to obtain PET image pairs (each patient was scanned once). For low-quality PET (LQ-PET) images with a 320-mm AFOV, we applied a 300-mm FOV for brain reconstruction and a 500-mm FOV for lung and abdomen reconstruction. For high-quality PET (HQ-PET) images, we applied a 1940-mm AFOV during the reconstruction process. A 3D Unet was utilized to learn the mapping relationship between LQ-PET and HQ-PET images. In addition, the peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) were employed to evaluate the model performance. Furthermore, two nuclear medicine doctors evaluated the image quality based on clinical readings. RESULTS: The generated PET images of the brain, lung, and abdomen were quantitatively and qualitatively compatible with the HQ-PET images. In particular, our method achieved PSNR values of 35.41 ± 5.45 dB (p < 0.05), 33.77 ± 6.18 dB (p < 0.05), and 38.58 ± 7.28 dB (p < 0.05) for the three beds. The overall mean SSIM was greater than 0.94 for all patients who underwent testing. Moreover, the total subjective quality levels of the generated PET images for three beds were 3.74 ± 0.74, 3.69 ± 0.81, and 3.42 ± 0.99 (the highest possible score was 5, and the minimum score was 1) from two experienced nuclear medicine experts. Additionally, we evaluated the distribution of quantitative standard uptake values (SUV) in the region of interest (ROI). Both the SUV distribution and the peaks of the profile show that our results are consistent with the HQ-PET images, proving the superiority of our approach. CONCLUSION: The findings demonstrate the potential of the proposed technique for improving the image quality of a PET scanner with a 320 mm or even shorter AFOV. Furthermore, this study explored the potential of utilizing uEXPLORER to achieve improved short-axis PET image quality at a limited economic cost, and computer-aided diagnosis systems that are related can help patients and radiologists.

Comparison between the long-axis in-plane and short-axis out-of-plane approaches for ultrasound-guided arterial cannulation: a meta-analysis and systematic review.

BACKGROUND: The two most common methods for ultrasound-guided arterial cannulation are the long-axis in-plane (LA-IP) and short-axis out-of-plane (SA-OOP) approaches. However, it is uncertain which method is more advantageous. We conducted a meta-analysis of reported randomized clinical trials (RCTs) comparing the two techniques in terms of success rate, cannulation time, and complications. METHODS: We systematically searched PubMed, Embase, and the Cochrane Library database for RCTs comparing the LA-IP and SA-OOP techniques for ultrasound-guided arterial cannulation published from inception through April 31, 2022. The Cochrane Collaboration's Risk of Bias Tool was used to evaluate the methodological quality of each RCT. Review Manager 5.4 and Stata/SE 17.0 were used to analyze the two primary outcome measures (first-attempt success rate and total success rate) and two secondary outcome measures (cannulation time and complications). RESULTS: A total of 13 RCTs with 1,377 patients were included. There were no significant differences in first-attempt success rate (risk ratio [RR], 0.93; 95% confidence interval [CI], 0.78-1.12; P = 0.45; I2 = 84%) and overall success rate (RR, 0.99; 95% CI, 0.95-1.02; P = 0.48; I2 = 57%). When compared with the LA-IP technique, the SA-OOP technique was associated with an increased incidence of posterior wall puncture (RR, 3.01; 95% CI, 1.27-7.14; P = 0.01; I2 = 79%) and hematoma (RR, 2.15; 95% CI, 1.05-4.37; P = 0.04; I2 = 63%). There was no significant difference in the incidence of vasospasm between techniques (RR, 1.26; 95% CI, 0.37-4.23; P = 0.07; I2 = 53%). CONCLUSIONS: The present results suggest that the SA-OOP technique is associated with a higher incidence of posterior wall puncture and hematoma than the LA-IP technique, whereas success rates are similar for the two ultrasound-guided arterial cannulation techniques. These findings should be experimentally evaluated in a more rigorous manner due to high inter-RCT heterogeneity.

Short Axis In-Plane Ultrasound-Guided Technique for Internal Jugular Vein Cannulation.

BACKGROUND: Real-time ultrasound (US)-guided venipuncture has become the standard of care due to its reduced complications and higher success rate. There are various techniques for US-guided cannulation of the internal jugular vein (IJV); the transversal and longitudinal views are the most widely used. There is a less commonly used technique that combines the benefits of both methods. DISCUSSION: Two main techniques for central line US-guided cannulation of the IJV are based on the location of the probe relative to the vessel and are known as the transversal view and the longitudinal view. The transversal view may make it difficult to identify the tip of the needle as it enters the vein, and the longitudinal view may not allow for visualization of surrounding structures. A third and less commonly used technique, the short axis in-plan view, aims to combine the benefits of both previous methods. In this technique, the entire needle can be tracked in real time as it enters the IJV, while also providing visualization of surrounding structures. CONCLUSIONS: The short axis in-plane view technique for central venous line placements allows for real-time US-guided needle venipuncture with simultaneous visualization of surrounding structures.

Short-term prognostic value of clinical data in hospitalized patients with intermediate-risk acute pulmonary embolism.

BACKGROUND: Intermediate-risk acute pulmonary embolism (APE) patients are usually defined as hemodynamically stable, comprehending a great therapeutic dilemma. Although anticoagulation therapy is sufficient for most intermediate-risk APE patients, some patients can deteriorate and eventually require a systemic fibrinolytic agent or thrombectomy. Hence, this study aimed to evaluate the predictive value of differences in clinical data for the short-term prognosis of intermediate-risk APE patients. METHODS: A retrospective cohort of 74 intermediate-risk APE patients confirmed by computed tomography pulmonary angiography was analyzed in the present study. Adverse clinical event outcomes included PE-related in-hospital deaths, critical systolic blood pressure consistently under 90 mmHg, refractory to volume loading and vasopressor infusion requirements, mechanical ventilation, and cardiopulmonary resuscitation. The APE patients were stratified into two groups: adverse outcome (n = 25) and control (n = 49) groups. Then, the clinical data of the two groups were compared. Receiver operating characteristic (ROC) curves were used to explore the predictive value of white blood cell (WBC) counts and the right to left ventricular short-axis (RV/LV) ratio. Model calibration was assessed using the Hosmer-Lemeshow goodness-of-fit statistic. RESULTS: The brain natriuretic peptide, WBC count, and the RV/LV ratio were higher in patients with adverse outcomes compared to controls. The APE patients with adverse outcomes presented significantly higher rates of syncope, Negative T waves (NTW) in V1-V3, intermediate-high risk, thrombolytic therapy, and low arterial oxygen saturation (SaO2) compared to controls. In the multivariate logistic regression analysis, the SaO2 < 90%, [odds ratio (OR) 5.343, 95% confidence interval (CI) 1.241-23.008; p = 0.024], RV/LV ratio (OR 7.429, 95% CI 1.145-48.209; p = 0.036), Syncope (OR 12.309, 95% CI 1.702-89.032; p = 0.013), NTW in V1-V3 (OR 5.617, 95% CI 1.228-25.683; p = 0.026), and WBC count (OR 1.212, 95% CI 1.035-1.419; p = 0.017) were independent predictors of in-hospital adverse outcomes among APE patients. The ROC curve analysis indicated that the RV/LV ratio can be used to predict adverse outcomes (AUC = 0.748, p < 0.01) and calibration (Hosmer-Lemeshow goodness of fit test, p = 0.070). Moreover, an RV/LV ratio > 1.165 was predictive of adverse outcomes with sensitivity and specificity of 88.00 and 59.20%, respectively. The WBC counts were also able to predict adverse outcomes (AUC = 0.752, p < 0.01) and calibration (Hosmer-Lemeshow goodness of fit test, p = 0.251). A WBC count > 9.05 was predictive of adverse outcomes with sensitivity and specificity of 68.00 and 73.50%, respectively. CONCLUSION: Overall, a SaO2 < 90%, RV/LV ratio, Syncope, NTW in V1-V3, and WBC counts could independently predict adverse outcomes in hospitalized intermediate-risk APE patients.

Using aortic arch short axis views during transesophageal echocardiographic examination facilitates right ventricular assist device imaging.

Given the increased need for mechanical circulatory support and subsequent development of right ventricular assist devices (RVAD), appropriate imaging needs to be described to facilitate care in patients with cardiogenic shock and heart failure. We present three cases in which the upper esophageal aortic arch short axis (UE AA SAX) view on transesophageal echocardiography (TEE) was utilized to effectively image RVADs: to confirm normal positioning, to detect and guide repositioning, and to visualize malfunction. These cases support the importance of the UE AA SAX TEE view in RVAD outflow imaging and, when obtainable, should be included in routine RVAD assessment.

US-guided FNA techniques for thyroid nodules is the short axis better than the long axis?

BACKGROUND: Ultrasound-guided fine needle aspiration cytology (FNAC US) has been proven to be an accurate and efficient tool in thyroid nodule evaluation. Thyroid nodule aspiration can be acquired with either of two techniques: the short axis, in which only the tip of the needle is observed, and the long axis, in which the entire length of the needle is observed. Our retrospective study aimed to compare the adequacy of the two techniques. METHODS: FNAC US was performed in 538 thyroid nodules between January 2019 and December 2021. Data on the technique and the diagnostic accuracy were collected. RESULTS: A total of 273 nodules were aspirated using the long axis technique, and 265 nodules were aspirated using the short axis technique. The diagnostic adequacies of the long axis technique were significantly higher than those of the short axis technique (92 % versus 86 %, respectively, p < 0.025). CONCLUSION: In our study, the long axis technique provided more accurate cytological evaluation than the short axis technique. LEVEL OF EVIDENCE: level 3.

A deep learning pipeline for automatic analysis of multi-scan cardiovascular magnetic resonance.

BACKGROUND: Cardiovascular magnetic resonance (CMR) sequences are commonly used to obtain a complete description of the function and structure of the heart, provided that accurate measurements are extracted from images. New methods of extraction of information are being developed, among them, deep neural networks are powerful tools that showed the ability to perform fast and accurate segmentation. Iq1n order to reduce the time spent by reading physicians to process data and minimize intra- and inter-observer variability, we propose a fully automatic multi-scan CMR image analysis pipeline. METHODS: Sequence specific U-Net 2D models were trained to perform the segmentation of the left ventricle (LV), right ventricle (RV) and aorta in cine short-axis, late gadolinium enhancement (LGE), native T1 map, post-contrast T1, native T2 map and aortic flow sequences depending on the need. The models were trained and tested on a set of data manually segmented by experts using semi-automatic and manual tools. A set of parameters were computed from the resulting segmentations such as the left ventricular and right ventricular ejection fraction (EF), LGE scar percentage, the mean T1, T1 post, T2 values within the myocardium, and aortic flow. The Dice similarity coefficient, Hausdorff distance, mean surface distance, and Pearson correlation coefficient R were used to assess and compare the results of the U-Net based pipeline with intra-observer variability. Additionally, the pipeline was validated on two clinical studies. RESULTS: The sequence specific U-Net 2D models trained achieved fast (≤ 0.2 s/image on GPU) and precise segmentation over all the targeted region of interest with high Dice scores (= 0.91 for LV, = 0.92 for RV, = 0.93 for Aorta in average) comparable to intra-observer Dice scores (= 0.86 for LV, = 0.87 for RV, = 0.95 for aorta flow in average). The automatically and manually computed parameters were highly correlated (R = 0.91 in average) showing results superior to the intra-observer variability (R = 0.85 in average) for every sequence presented here. CONCLUSION: The proposed pipeline allows for fast and robust analysis of large CMR studies while guaranteeing reproducibility, hence potentially improving patient's diagnosis as well as clinical studies outcome.

Comparison of short- and long-axis nerve hydrodissection for carpal tunnel syndrome: A prospective randomized, single-blind trial.

Background: This study is to compare the efficacy of short-axis hydrodissection with long-axis hydrodissection for patients with mild-to-moderate carpal tunnel syndrome (CTS). Methods: Forty-seven patients with mild-to-moderate CTS were enrolled in a prospective, randomized, single-blinded, controlled trial (6 months follow-up). With ultrasound guidance, patients in both groups (short-axis or long-axis groups) were injected with normal saline (5 mL per session). Assessments were performed before and 2 weeks after the injection, as well as at 1, 3, and 6 months post-intervention. The primary outcome measure was the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) score and secondary outcomes included the cross-sectional area of the median nerve and electrophysiological studies. Results: Forty-four patients (21 wrists in the short-axis group and 23 wrists in the long-axis group) completed the study. Compared with the baseline, both groups showed improved BCTQ and cross-sectional area at all follow-up assessments (p<0.05). The short-axis group was not more effective except significant improvements in BCTQ-severity and BCTQ-function 1 month post-injection compared to the long-axis group (p = 0.031 and p = 0.023, respectively). Conclusions: Both short- and long-axis hydrodissection were effective for patients with mild-to-moderate CTS and the short-axis approach was not more effective than long-axis injection. Further studies with larger sample sizes, multiple injections, and larger injection volume are encouraged in the future.

Combined short- and long-axis method for internal jugular vein catheterization in premature newborns: A randomized controlled trial.

BACKGROUND: Rapid central venous catheterization is critical for the rescue and perioperative management of premature infants requiring surgery. Ultrasound-guided dynamic needle tip positioning (DNTP) has been widely used as a very effective technique, especially in paediatric vascular puncture and catheterization. However, for low-weight premature newborns, central vein catheterization still poses greater difficulties for paediatricians and paediatric anaesthesiologists. This prospective randomized control study aimed to evaluate the efficacy of combined short- and long-axis (CSLA) internal jugular vein catheterization for premature newborns in comparison with the DNTP technique. METHODS: A total of 90 premature newborns (gestational age < 37 weeks and < 28 days after birth) who were scheduled for surgery were included in this study. All enrolled premature newborns were randomly divided into two groups (n = 45): the CSLA group and the DNTP group. We compared the first-puncture success rate, total success rate, procedure time, number of needle passes, occurrence of complications and other outcome measures between the two groups. RESULTS: The two groups (n = 45 per group) were similar in sex, gestational age, weight, mean arterial blood pressure, and vein-related measurements of the internal jugular vein. Total success was achieved in 43 (95.6%) and 36 (80.0%) patients in the CSLA and DNTP groups respectively. Compared with the DNTP group, the CSLA group showed a significantly higher first-attempt success rate (71.1% vs 46.7%, χ2  = 5.5533, P = .0184) and significantly fewer needle passes (1.0[1.0-2.0] vs 2.0[1.0-3.0], χ2  = -2.6094, P = .0091). There was no significant difference between the groups in the procedure time (368[304-573] vs 478[324-79]s, Z = -1.7690, P = .0769). Complications occurred in both groups, but the incidence was significantly lower in the CSLA group than in the DNTP group (6.7% vs 22.2%, χ2  = 4.4056, P = .0358). CONCLUSIONS: Ultrasound-guided internal jugular vein catheterization by the CSLA method is effective and safe. The CSLA method may be superior to the DNTP technique in premature newborns.

CT reconstruction with thick slices not only underestimates lymph node size but also reduces data reproducibility in colorectal cancer.

BACKGROUND: Reliable size measurement of lymph node (LN) metastases is important for the evaluation of cancer treatment. However, image analyses without proper settings may result in inappropriate diagnoses and staging. PURPOSE: To investigate whether reconstruction slice thickness in computed tomography (CT) affects measurements of LN size and reproducibility. MATERIAL AND METHODS: We analyzed 48 patients with histological diagnoses of sigmoid colon and rectal cancer who underwent contrast-enhanced CT colonography as part of a surgical treatment preparation. A board-certified radiologist selected 106 LNs whose short-axis diameter was ≥5 mm on 1-mm-thick images; the short-axis diameters were measured on 1- and 5-mm-thick images by the radiologist and residents and compared using Wilcoxon matched-pairs signed rank test. Data variation and reproducibility were evaluated using the F test and Bland-Altman analysis. P<0.05 was considered significant. RESULTS: Short-axis diameters measured on 5-mm-thick images were significantly lower than those measured on 1-mm-thick images (P<0.01), even in the LNs whose short-axis diameters were over twice the slice thickness (P<0.05). Of the 106 LNs, 57 showed short-axis diameter <5 mm on 5-mm-thick images; the maximum short-axis diameter was 6.7 mm on a 1-mm thick image. Data variation was significantly larger on 5-mm thick images than 1-mm-thick images in small LNs (P<0.05) and reproducibility on 5-mm-thick images was inferior to that on 1-mm-thick images. CONCLUSION: Thick reconstruction slices in CT can result in an underestimation of LN size and reduce data reproducibility. When measuring LN size, a thin reconstruction slice would be recommended based on targeted LN size.

Internal Jugular Vein Cannulation Using a 3-Dimensional Ultrasound Probe in Patients Undergoing Cardiac Surgery: Comparison Between Biplane View and Short-Axis View.

OBJECTIVE: To compare the clinical performance in terms of procedure time, success rate, and cannulation attempts between ultrasound biplane view (BPX) and short-axis (SAX) view for internal jugular vein cannulation (IJV) in patients undergoing cardiac surgery. DESIGN: Prospective, observational pilot study. SETTING: University level tertiary referral hospital. PATIENTS: The study comprised 100 patients between ages 18 and 75 years undergoing elective cardiac surgery. INTERVENTIONS: One hundred patients were divided into 2 groups of 50 (BPX group and SAX group) by assigning the study participants alternatively to each group. IJV cannulation was performed using a 3-dimensional ultrasound probe in all patients with either BPX view (BPX group, n = 50) or the SAX view (SAX group, n = 50) by an experienced anesthesiologist. MEASUREMENTS AND MAIN RESULTS: Time required for imaging, time for IJV puncture, time for guidewire confirmation, number of needle punctures and needle redirections, and incidence of posterior wall puncture were noted in both groups. In addition, the quality of needle visualization and the incidence of complications were recorded. The time taken for imaging was significantly greater in the BPX group than in the SAX group (9.52 ± 2.69 s v 7.94 ± 2.55 s; p = 0.0034), whereas the time taken for IJV puncture (10.39 ± 2.33 s v 23.7 ± 2.46 s; p < 0.0001), time taken for confirmation of guidewire (32.94 ± 4.50 s v 57.64 ± 7.14 s; p < 0.0001), and the incidence of posterior wall puncture (4% v 26%; p = 0.0022) were significantly less in the BPX group than in the SAX group. The total number of attempts taken to puncture the IJV was fewer in the BPX group than in the SAX group (55 v 78). Successful puncture of the IJV occurred on the first attempt in 90% of patients in the BPX group, whereas it was only 50% in the SAX group (p < 0.0001). The quality of needle visualization was good in 90% of patients in the BPX group, whereas it was only 6% in the SAX group. The number of needle redirections for IJV puncture was less in the BPX group than in the SAX group (48 v 116). The incidence of complications was not significant between the 2 groups. CONCLUSION: The results suggested that the BPX view may be a safer, feasible and more reliable method than the SAX view for IJV cannulation in cardiac surgical patients.

Syringe-Free, Long-Axis in-Plane Versus Short-Axis Classic out-of-Plane Approach for Ultrasound-Guided Internal Jugular Vein Catheter Placement in Critically Ill Children: A Prospective Randomized Study.

OBJECTIVE: Although pediatric central venous catheterization is performed using ultrasound guidance, it is still a challenge. This study aimed to investigate the efficacy of the syringe-free, long-axis in-plane approach and compared the short-axis classic out-of-plane approach for ultrasound-guided central venous catheter placement in critically ill pediatric patients. DESIGN: Prospective randomized study. SETTING: Single institution, tertiary university hospital, pediatric care unit. PARTICIPANTS: The study comprised 60 patients ages three months to 15 years. INTERVENTIONS: Participants were randomly divided into two equal groups. Group I (n = 30) incorporated patients who underwent the long-axis, syringe-free in-plane approach, and group II (n = 30) incorporated patients who underwent the short-axis out-of-plane approach. MEASUREMENTS AND MAIN RESULTS: Performing time, number of needle passes, number of skin punctures, first-pass success rate, and related complications were evaluated. There were no differences between the two groups in terms of demographics and vein-related measurements (p > 0.05). Performing time was statistically shorter in group I compared with group II (32 [25-38] v 58 [42-70] s; p < 0.001). There was no statistical difference between first-pass success rates between groups (group I 86.6% v group II 80%; p = 0.731). There were no significant differences between the groups in the number of needle passes and skin punctures (p = 0.219 and 0.508, respectively). Complications occurred in both groups, but there was no significant difference (4/30 v 7/30; p = 0.317). CONCLUSIONS: The syringe-free, long-axis in-plane approach can be a safe and fast alternative for pediatric catheterization.

Incidence of posterior vessel wall puncture during ultrasound guided vascular access: Short axis versus long axis approach.

BACKGROUND AND AIMS: Posterior vessel wall puncture (PVWP) is a common complication of ultrasound (US) guided central venous cannulation. We evaluated and compared the frequency of PWVP of internal jugular vein using short axis (SA) and long axis (LA) approach of US-guided needle cannulation. As a secondary objective incidence of carotid puncture was assessed. MATERIAL AND METHODS: Prospective, single-blinded, cross over, observational study at Urban Level I Neuroanesthesiology and Critical Care Department. Residents receiving standard education on ultrasound-guided central venous cannulation were asked to place an US-guided catheter using either short axis or long axis approach on a human torso mannequin. During the procedure, the path of the needle was carefully observed by the investigator for any PVWP and carotid puncture without interference with the placement procedure. The confidence level of the resident for the intraluminal placement of the needle tip was measured on a 10-point Likert scale. RESULTS: Forty residents participated in the study. The incidence of PVWP in SA and LA group was 40% and 17.5% respectively and was statistically significant (p = 0.026). There was no incidence of carotid artery puncture in either of the group. The mean confidence of intraluminal placement of needle was significantly higher in the LA group (8.32) as compared to the SA group (5.95). CONCLUSION: Lower incidence of PVWP was seen in LA as compared to the SA approach during US-guided IJV cannulation in phantom in residents having previous experience of CVC (central venous cannulation) in landmark technique only. Participants were more confident about intraluminal needle placement in the LA group compared to the SA group.

Diagnostic Accuracy of Mapping Techniques and Postprocessing Methods for Acute Myocarditis.

OBJECTIVE. Many T1 mapping sequences and measurement methods have been reported in the literature. To obtain accurate results, the most appropriate T1 and T2 mapping sequences and postprocessing methods should be used. The aim of the present study is to compare the T1 and T2 mapping sequences and measurement methods used to diagnose acute myocarditis. MATERIALS AND METHODS. Fourteen patients with an interval of 7 days or less between symptom onset and MRI examination were included in the study. The control group consisted of 22 healthy individuals. T1 mapping images acquired using four different methods (modified Look-Locker inversion recovery [MOLLI] 3[3]3[3]5, MOLLI 3[2]3[2]5, MOLLI 5[3]3 heart rate-corrected, and MOLLI 5[3]3 heart rate-uncorrected sequences) and T2 mapping images obtained using two different methods (FLASH and true fast imaging with steady-state precession) in the area from the short axis through the basal slice were retrospectively evaluated. RESULTS. The mean T1 and T2 values were significantly higher in the patient group than in the control group for all sequences in SAX measurements and segmental measurements (segments 1, 4, 5, and 6). Measurements from segments 2 and 3 were not statistically significant between patient and control groups. The segment with the highest AUC value of T1 and T2 mapping values was the inferior segment, followed by the inferolateral segment. The highest diagnostic performance for short-axis measurements was obtained using the MOLLI 3(2)3(2)5 sequence (AUC value = 0.902). CONCLUSION. According to the results of this study and many other studies, pathologic changes in the myocardium can be detected by native T1 and T2 mapping. The accuracy of mapping methods will increase with increased knowledge of the advantages and disadvantages of currently used sequences and measurement methods.

Evaluating the Long-, Short-, and Oblique-Axis Approaches for Ultrasound-Guided Vascular Access Cannulation.

BACKGROUND: Our goal was to conduct a network meta-analysis of randomized controlled trials to compare the effects of the long-axis (LAX), short-axis (SAX), and oblique-axis (OAX) ultrasound guidance approaches for vascular access cannulation. METHODS: We searched 5 databases, including the Cochrane Central Register of Controlled Trials in the Cochrane Library, Embase, MEDLINE, CINAHL, and Web of Science. Seven randomized clinical trials assessing ultrasound guidance for vascular access cannulation via the LAX, SAX, or OAX approach were included. The primary end point was the first-pass success rate. Secondary end points included the mean time to success and average number of attempts until success. We used random-effects models to calculate weighted mean differences with 95% confidence intervals for continuous outcomes and relative risks with 95% confidence intervals for dichotomous outcomes. RESULTS: There were no significant differences between the LAX, SAX, and OAX techniques with respect to the first-pass success rate, mean time to success, average number of attempts until success, or the incidence of hematoma. CONCLUSION: There was insufficient evidence to definitively recommend the LAX, SAX, or OAX approach for patients undergoing ultrasound-guided vascular access cannulation.

Ultrasound-guided central venous catheter placement: a structured review and recommendations for clinical practice.

The use of ultrasound (US) has been proposed to reduce the number of complications and to increase the safety and quality of central venous catheter (CVC) placement. In this review, we describe the rationale for the use of US during CVC placement, the basic principles of this technique, and the current evidence and existing guidelines for its use. In addition, we recommend a structured approach for US-guided central venous access for clinical practice. Static and real-time US can be used to visualize the anatomy and patency of the target vein in a short-axis and a long-axis view. US-guided needle advancement can be performed in an "out-of-plane" and an "in-plane" technique. There is clear evidence that US offers gains in safety and quality during CVC placement in the internal jugular vein. For the subclavian and femoral veins, US offers small gains in safety and quality. Based on the available evidence from clinical studies, several guidelines from medical societies strongly recommend the use of US for CVC placement in the internal jugular vein. Data from survey studies show that there is still a gap between the existing evidence and guidelines and the use of US in clinical practice. For clinical practice, we recommend a six-step systematic approach for US-guided central venous access that includes assessing the target vein (anatomy and vessel localization, vessel patency), using real-time US guidance for puncture of the vein, and confirming the correct needle, wire, and catheter position in the vein. To achieve the best skill level for CVC placement the knowledge from anatomic landmark techniques and the knowledge from US-guided CVC placement need to be combined and integrated.

Comparison of short-axis out-of-plane versus long-axis in-plane ultrasound-guided radial arterial cannulation in adult patients: a randomized controlled trial.

BACKGROUND: The current available literature is not unanimous in reporting the utility of short-axis and long-axis techniques for radial artery cannulation in both adults and children. This study was designed to compare short-axis out-of-plane (SA-OOP) and long-axis in-plane (LA-IP) techniques in ultrasound-guided radial artery cannulation in adults. METHODS: In this prospective randomized controlled trial, 150 adult patients of American Society of Anesthesiologists physical status I-III aged between 18 and 70 years were included. All patients were randomized into two groups (group SA-OOP) and (group LA-IP) of 75 each undergoing ultrasound-guided radial artery cannulation. The primary outcome was successful cannulation in the first attempt. Secondary outcomes included antero-posterior arterial diameter, skin-to-artery distance, ultrasonic localization time, cannulation time, no of attempts to cannulate artery, cannula insertion failure, and vascular complications. RESULTS: First-attempt arterial cannulation was successful in 80 % of patients in the SA-OOP group as opposed to 82.6 % patients in the LA-IP group (p = 0.67). The time to cannulate the artery was similar between the two groups, but the time to localize artery was significantly higher in the long-axis technique (p < 0.001). CONCLUSIONS: The first-attempt cannulation success rate and cannulation time in adult patients are similar in ultrasound-guided radial artery cannulation with both short-axis as well as long-axis techniques. Trial registration Clinical Trial Registry of India (CTRI/2015/02/005552).

Fast susceptibility-weighted imaging with three-dimensional short-axis propeller (SAP)-echo-planar imaging.

BACKGROUND: Susceptibility-weighted imaging (SWI) in neuroimaging can be challenging due to long scan times of three-dimensional (3D) gradient recalled echo (GRE), while faster techniques such as 3D interleaved echo-planar imaging (iEPI) are prone to motion artifacts. Here we outline and implement a 3D short-axis propeller echo-planar imaging (SAP-EPI) trajectory as a faster, motion-correctable approach for SWI. METHODS: Experiments were conducted on a 3T MRI system. The 3D SAP-EPI, 3D iEPI, and 3D GRE SWI scans were acquired on two volunteers. Controlled motion experiments were conducted to test the motion-correction capability of 3D SAP-EPI. The 3D SAP-EPI SWI data were acquired on two pediatric patients as a potential alternative to 2D GRE used clinically. RESULTS: The 3D GRE images had a better target resolution (0.47 × 0.94 × 2 mm, scan time = 5 min), iEPI and SAP-EPI images (resolution = 0.94 × 0.94 × 2 mm) were acquired in a faster scan time (1:52 min) with twice the brain coverage. SAP-EPI showed motion-correction capability and some immunity to undersampling from rejected data. CONCLUSION: While 3D SAP-EPI suffers from some geometric distortion, its short scan time and motion-correction capability suggest that SAP-EPI may be a useful alternative to GRE and iEPI for use in SWI, particularly in uncooperative patients.