Landmark Guidance Research Articles

Comparison of penile block using the reverse US-guided nerve block or landmark guidance during circumcision in pediatric population: a retrospective study

Comparison of penile block using the reverse US-guided nerve block or landmark guidance during circumcision in pediatric population: a retrospective study

Use of ultrasound for vascular access during cardiac catheterisation in children with congenital heart disease: a Swiss multicentre cohort study.

Our study aimed to assess the first-attempt success rate of ultrasound (US) and anatomical landmark (ALM) guidance for vascular cannulation in children with congenital heart disease in Switzerland. A prospective observational multicentre study was conducted from January 2022 to January 2023 in three university hospitals in Switzerland. We included patients with congenital heart disease aged 0 to 18 years who were scheduled for elective cardiac catheterisation. Periprocedural data were collected anonymously. The choice of vessel and guidance technique were at the operator's discretion. 177 arterial and 240 venous cannulations in 253 patients were analysed. The median age and weight were 4.4 years (interquartile range [IQR] 1.2-8.8) and 15 kg (IQR 8-27), respectively. Nearly all operators, 97.5%, were deemed experienced. The femoral artery and femoral vein were the most preferred vessels. US guidance was used in 62% of procedures, predominantly within populations who were younger, smaller and of lower weight.The success rate at the first attempt was notably higher with US guidance for arterial cannulation (US: 80%, ALM: 37%, p <0.001) and venous cannulation (US: 78% vs ALM: 47%, p <0.001). Overall success rates for venous and arterial cannulation were comparable between ultrasound and anatomical landmark guidance. A total of 45 complications (10.5%) occurred, with immediate uncomplicated haematoma being the most frequent. US guidance is preferred for the localisation and cannulation of vessels during cardiac catheterisation within paediatric cardiology departments in Switzerland. Given its high success rate for first-attempt cannulation, US warrants additional research to evaluate its potential in reducing complications.

Parallel vector memories in the brain of a bee as foundation for flexible navigation

Insects rely on path integration (vector-based navigation) and landmark guidance to perform sophisticated navigational feats, rivaling those seen in mammals. Bees in particular exhibit complex navigation behaviors including creating optimal routes and novel shortcuts between locations, an ability historically indicative of the presence of a cognitive map. A mammalian cognitive map has been widely accepted. However, in insects, the existence of a centralized cognitive map is highly contentious. Using a controlled laboratory assay that condenses foraging behaviors to short distances in walking bumblebees, we reveal that vectors learned during path integration can be transferred to long-term memory, that multiple such vectors can be stored in parallel, and that these vectors can be recalled at a familiar location and used for homeward navigation. These findings demonstrate that bees meet the two fundamental requirements of a vector-based analog of a decentralized cognitive map: Home vectors need to be stored in long-term memory and need to be recalled from remembered locations. Thus, our data demonstrate that bees possess the foundational elements for a vector-based map. By utilizing this relatively simple strategy for spatial organization, insects may achieve high-level navigation behaviors seen in vertebrates with the limited number of neurons in their brains, circumventing the computational requirements associated with the cognitive maps of mammals.

Comparison of ultrasound guidance with landmark guidance for symptomatic benefits in knee, hip and hand osteoarthritis: Systematic review and meta‐analysis of randomised controlled trials

AbstractIntroductionMore than half of the patients with moderate and severe osteoarthritis (OA) report unsatisfactory pain relief, requiring consideration of intra‐articular (IA) injections as the second‐line management. Ultrasound‐guided IA injection has proven evidence of higher accuracy in administering IA injectates into the joints than landmark‐guided or blind IA injections. However, questions remain about translating higher accuracy rates of ultrasound‐guided injection into better clinical improvements. Therefore, we examined the symptomatic benefits (pain, function and patient satisfaction) of ultrasound‐guided injection in knee, hip and hand OA compared with blind injections by synthesising a systematic review and meta‐analysis of randomised controlled trials (RCT).MethodsPubMed, Medline and Embase databases were searched for eligible studies from their inception to August 28, 2023.ResultsOut of 295 records, our meta‐analysis included four RCTs (338 patients with knee OA), demonstrating significant improvement in procedural pain [−0.89 (95% CI −1.25, −0.53)], pain at follow‐up [−0.51 (95% CI −0.98, −0.04)] and function [1.30 (95% CI 0.86, 1.73)], favouring ultrasound guidance. One single study showed higher patient satisfaction with ultrasound guidance.ConclusionUltrasound‐guided IA injection provided superior clinical outcomes compared with landmark‐guided IA injection.

Navigational Competency is Mediated by Foraging Experience and Light Conditions in the Nocturnal Bull Ant Myrmecia midas

The nocturnal bull ants of the genus Myrmecia, Myrmecia midas travel in both bright and dim settings on the ground and also vertically up on trees navigating towards targets. It is known that foragers retain multiple panoramic memories of terrestrial landmarks as well as celestial cues along their foraging route. It is likely that they can compare these stored views with their current visual input to return to their nest. Here we examined whether nocturnal M. midas foragers’ navigational efficiency and success at view-based navigation suffer at low light levels (night time) compared with daylight levels of brightness. When exposed to panoramic cues in dim conditions, which had dimmer light levels than their peak foraging period, they were less well oriented and less likely to find the nest, with the catchment area smaller at night than during the day. At different displacement distances from the nest, initial navigational behaviours differed. Foragers displayed more scanning near the starting point at shorter distances, while with increasing distance they switched more to loops of systematic searching or heading off in some direction without scans. In the dim conditions, landmark guidance became less effective, perhaps explaining why foragers limit their navigational activities mostly to the twilight hours, when light levels are still adequate, and mostly forage in a tree through the night.

Direct MR arthrography of the hip joint: anterior approach without imaging guidance.

The purpose of this study is to describe the anterior injection approach, with anatomical landmark guidance, for direct MR arthrography (dMRA) of the hip joint, and to evaluate the effectiveness in joint distension and the security of the technique. Retrospective review of hip dMRAs was conducted on patients with suspected intra-articular pathology from two MR outpatient centers, performed by two radiologists with 25 and 5years of experience, respectively. The analysis included assessing the presence of intra-articular contrast material (gadolinium-based solution), the number of injections performed, the degree of joint distension, and the degree of contrast extravasation. A multi-variant analysis was carried out to determine if the procedure success depend on any of the demographic variants or on the radiologist experience. Additionally, the presence of immediate and medium-term post-puncture complications was evaluated. One hundred patients with 104 hip dMRA were included; 60 were men, with mean age of 38years (16-63years). Contrast material was successfully introduced intra-articularly in 100% of patients, being necessary a second puncture only in 6% of procedures. The capsular distension was considered optimal for diagnosis in 97% of cases. Different degrees of contrast extravasation were found in 30% of dMRA. There was no statistically significant relationship observed between patient variables and the performance of dMRA, nor did it show any correlation with the experience of the radiologists. No puncture-derived complications were found. Hip dMRA through anterior injection guided by anatomical references is an effective and safe alternative for patients with suspected intra-articular pathology.

Developing the surgeon-machine interface: using a novel instance-segmentation framework for intraoperative landmark labelling.

The utilisation of artificial intelligence (AI) augments intraoperative safety, surgical training, and patient outcomes. We introduce the term Surgeon-Machine Interface (SMI) to describe this innovative intersection between surgeons and machine inference. A custom deep computer vision (CV) architecture within a sparse labelling paradigm was developed, specifically tailored to conceptualise the SMI. This platform demonstrates the ability to perform instance segmentation on anatomical landmarks and tools from a single open spinal dural arteriovenous fistula (dAVF) surgery video dataset. Our custom deep convolutional neural network was based on SOLOv2 architecture for precise, instance-level segmentation of surgical video data. Test video consisted of 8520 frames, with sparse labelling of only 133 frames annotated for training. Accuracy and inference time, assessed using F1-score and mean Average Precision (mAP), were compared against current state-of-the-art architectures on a separate test set of 85 additionally annotated frames. Our SMI demonstrated superior accuracy and computing speed compared to these frameworks. The F1-score and mAP achieved by our platform were 17% and 15.2% respectively, surpassing MaskRCNN (15.2%, 13.9%), YOLOv3 (5.4%, 11.9%), and SOLOv2 (3.1%, 10.4%). Considering detections that exceeded the Intersection over Union threshold of 50%, our platform achieved an impressive F1-score of 44.2% and mAP of 46.3%, outperforming MaskRCNN (41.3%, 43.5%), YOLOv3 (15%, 34.1%), and SOLOv2 (9%, 32.3%). Our platform demonstrated the fastest inference time (88ms), compared to MaskRCNN (90ms), SOLOV2 (100ms), and YOLOv3 (106ms). Finally, the minimal amount of training set demonstrated a good generalisation performance -our architecture successfully identified objects in a frame that were not included in the training or validation frames, indicating its ability to handle out-of-domain scenarios. We present our development of an innovative intraoperative SMI to demonstrate the future promise of advanced CV in the surgical domain. Through successful implementation in a microscopic dAVF surgery, our framework demonstrates superior performance over current state-of-the-art segmentation architectures in intraoperative landmark guidance with high sample efficiency, representing the most advanced AI-enabled surgical inference platform to date. Our future goals include transfer learning paradigms for scaling to additional surgery types, addressing clinical and technical limitations for performing real-time decoding, and ultimate enablement of a real-time neurosurgical guidance platform.

899 Administration of Fascia-Iliaca Blocks for Hip Fracture Patients on Admission to the A&amp;E Department at Southport DGH

Abstract Aim Fascia-iliaca block (FIB) is regional anaesthetic used in A&amp;E for hip fractures; they’re performed under landmark guidance in Southport A&amp;E. NICE recommend FIBs for hip fractures if PO/IV paracetamol/opiates provide insufficient relief; it’s shown to provide superior analgesia and reduce opiate consumption. RCEM state FIBs should be administered promptly in A&amp;E by trained personnel and are a listed ACCS competency. The audit aim was to review the number/percentage of hip fracture patients receiving FIBs, with documentation, in Southport A&amp;E. Hip fracture patients should have documented FIBs, the standard for the audit was ≥90% patients. Method This audit was a retrospective analysis of the 6-week period 08/08/2022-20/09/2022 for hip fracture patients at Southport DGH. Data was collected from the National Hip Fracture Database. Patients weren’t delayed to surgery on FIB administration. Online inpatient/A&amp;E notes and drug charts were analysed for FIB documentation. Results The sample included 46 patients, 8 male and 38 female. 13 had documented FIBs on admission, 33 had no documented FIB, meaning 28.2% of patients received FIBs in A&amp;E over 6-weeks. Conclusions This audit shows too few hip fracture patients are receiving FIBs in Southport A&amp;E as analgesia, with 28.2% documented compared to the desired ≥90% standard. Patients are either not receiving FIBs or not having them documented. FIB use can be improved by clinical audit, and interventions are being implemented to improve use in Southport A&amp;E, including posters, hip fracture proforma additions, and department education.

Measuring success: A comparison of ultrasound and landmark guidance for knee arthrocentesis in a cadaver model

ObjectiveKnee arthrocentesis can be performed by landmark (LM) or ultrasound (US) guidance. The goal of performing knee arthrocentesis is to obtain synovial fluid, however, it is also important to consider the number of attempts required and accidental bone contacts that occur. This study evaluates procedural success without bone contact in knee arthrocentesis and compares both LM and US guided techniques in a cadaver model. MethodsThis was a randomized crossover study comparing US vs LM guidance for arthrocentesis in a single academic center. Volunteers were randomized to perform both LM and US guided knee arthrocentesis on cadavers. The primary outcome was procedural success, defined as first attempt aspiration of synovial fluid without bone contact. Secondary outcomes included number of attempts, number of bone contacts, time to aspiration, and confidence. ResultsSixty-one participants completed the study with a total of 122 procedures performed. Procedural success without bone contact was greater in the US group (84% vs 64% p = 0.02). Time to aspiration was longer for US (38.75 s vs 25.54 s p = 0.004). Participants were more confident with US compared to LM both before the procedure on a Visual Analog Scale from 1 to 100 (29 vs 21 p = 0.03) as well as after the procedure (83 vs 69 p = 0.0001). Participants had a greater median increase in confidence with US following training (44 vs 26 p = 0.01). ConclusionsStudy participants had greater procedural success without bone contact when US guidance was used. The increase in confidence following training was greater for US guidance than the LM method. Use of US guidance may offer a benefit by allowing for better needle control and avoidance of sensitive structures for clinicians performing knee arthrocentesis.

Comparison of Landmark-Guided Versus Fluoroscopy-Guided Cerebrospinal Fluid Drain-Related Complications After Aortic Repairs

Cerebrospinal fluid drains (CSFDs) are efficacious in preventing spinal cord injury after thoracic or thoracoabdominal aortic repair with extensive coverage. Increasingly, fluoroscopy is used to guide placement instead of the traditional landmark-based approach, but it is unknown which approach is associated with fewer complications. A retrospective cohort study. In the operating room. Patients having undergone thoracic or thoracoabdominal aortic repair with a CSFD over a 7-year period at a single center. No intervention. Groups were reviewed and statistically compared with respect to baseline characteristics, ease of CSFD placement, and major and minor complications directly related to placement. A total of 150 CSFDs were placed with landmark guidance as opposed to 95 with fluoroscopy guidance. Compared to the landmark group, patients with fluoroscopy-guided CSFDs were older (p < 0.008), had lower American Society of Anesthesiologists physical status scores (p=0.008), required fewer CSFD placement attempts (p=0.011), had the CSFD in place for longer duration (p < 0.001), and had a similar incidence of CSFD-related complications (p > 0.999). Composites of both major (4.5% of cases) and minor CSFD-related complications (6.1% of cases), the primary outcomes of the study, occurred with similar incidences between the 2 groups (p > 0.999 for both comparisons) after adjusting potential confounders. In patients undergoing thoracic or thoracoabdominal aortic repairs, there were no significant differences in the risk of major and minor CSFD-related complications between fluoroscopic guidance and the landmark approach. Although the authors' institution is a high-volume center for this type of procedure, the study was limited by a small sample size. Hence, regardless of the technique used for the placement of CSFD, the risks related to the placement should be balanced carefully against the potential benefits resulting from spinal cord injury prevention. Fluoroscopy-aided insertion of CSFD requires fewer attempts and, hence, may be better tolerated by patients.

Ultrasound-Guided Interventions for Carpal Tunnel Syndrome: A Systematic Review and Meta-Analyses.

Carpal tunnel syndrome (CTS) is the most common peripheral entrapment, and recently, ultrasound-guided perineural injection (UPIT) and percutaneous flexor retinaculum release (UPCTR) have been utilized to treat CTS. However, no systematic review or meta-analysis has included both intervention types of ultrasound-guided interventions for CTS. Therefore, we performed this review using four databases (i.e., PubMed, EMBASE, Scopus, and Cochrane) to evaluate the quality of evidence, effectiveness, and safety of the published studies on ultrasound-guided interventions in CTS. Among sixty studies selected for systemic review, 20 randomized treatment comparison or controlled studies were included in six meta-analyses. Steroid UPIT with ultrasound guidance outperformed that with landmark guidance. UPIT with higher-dose steroids outperformed that with lower-dose steroids. UPIT with 5% dextrose in water (D5W) outperformed control injection and hydrodissection with high-volume D5W was superior to that with low-volume D5W. UPIT with platelet-rich plasma outperformed various control treatments. UPCTR outperformed open surgery in terms of symptom improvement but not functional improvement. No serious adverse events were reported in the studies reviewed. The findings suggest that both UPIT and UPCTR may provide clinically important benefits and appear safe. Further treatment comparison studies are required to determine comparative therapeutic efficacy.

No Need for Landmarks: An Embodied Neural Controller for Robust Insect-Like Navigation Behaviors.

Bayesian filters have been considered to help refine and develop theoretical views on spatial cell functions for self-localization. However, extending a Bayesian filter to reproduce insect-like navigation behaviors (e.g., home searching) remains an open and challenging problem. To address this problem, we propose an embodied neural controller for self-localization, foraging, backward homing (BH), and home searching of an advanced mobility sensor (AMOS)-driven insect-like robot. The controller, comprising a navigation module for the Bayesian self-localization and goal-directed control of AMOS and a locomotion module for coordinating the 18 joints of AMOS, leads to its robust insect-like navigation behaviors. As a result, the proposed controller enables AMOS to perform robust foraging, BH, and home searching against various levels of sensory noise, compared to conventional controllers. Its implementation relies only on self-localization and heading perception, rather than global positioning and landmark guidance. Interestingly, the proposed controller makes AMOS achieve spiral searching patterns comparable to those performed by real insects. We also demonstrated the performance of the controller for real-time indoor and outdoor navigation in a real insect-like robot without any landmark and cognitive map.

Segmentation-guided multi-modal registration of liver images for dose estimation in SIRT

PurposeSelective internal radiation therapy (SIRT) requires a good liver registration of multi-modality images to obtain precise dose prediction and measurement. This study investigated the feasibility of liver registration of CT and MR images, guided by segmentation of the liver and its landmarks. The influence of the resulting lesion registration on dose estimation was evaluated.MethodsThe liver segmentation was done with a convolutional neural network (CNN), and the landmarks were segmented manually. Our image-based registration software and its liver-segmentation-guided extension (CNN-guided) were tuned and evaluated with 49 CT and 26 MR images from 20 SIRT patients. Each liver registration was evaluated by the root mean square distance (RMSD) of mean surface distance between manually delineated liver contours and mass center distance between manually delineated landmarks (lesions, clips, etc.). The root mean square of RMSDs (RRMSD) was used to evaluate all liver registrations. The CNN-guided registration was further extended by incorporating landmark segmentations (CNN&LM-guided) to assess the value of additional landmark guidance. To evaluate the influence of segmentation-guided registration on dose estimation, mean dose and volume percentages receiving at least 70 Gy (V70) estimated on the 99mTc-labeled macro-aggregated albumin (99mTc-MAA) SPECT were computed, either based on lesions from the reference 99mTc-MAA CT (reference lesions) or from the registered floating CT or MR images (registered lesions) using the CNN- or CNN&LM-guided algorithms.ResultsThe RRMSD decreased for the floating CTs and MRs by 1.0 mm (11%) and 3.4 mm (34%) using CNN guidance for the image-based registration and by 2.1 mm (26%) and 1.4 mm (21%) using landmark guidance for the CNN-guided registration. The quartiles for the relative mean dose difference (the V70 difference) between the reference and registered lesions and their correlations [25th, 75th; r] are as follows: [− 5.5% (− 1.3%), 5.6% (3.4%); 0.97 (0.95)] and [− 12.3% (− 2.1%), 14.8% (2.9%); 0.96 (0.97)] for the CNN&LM- and CNN-guided CT to CT registrations, [− 7.7% (− 6.6%), 7.0% (3.1%); 0.97 (0.90)] and [− 15.1% (− 11.3%), 2.4% (2.5%); 0.91 (0.78)] for the CNN&LM- and CNN-guided MR to CT registrations.ConclusionGuidance by CNN liver segmentations and landmarks markedly improves the performance of the image-based registration. The small mean dose change between the reference and registered lesions demonstrates the feasibility of applying the CNN&LM- or CNN-guided registration to volume-level dose prediction. The CNN&LM- and CNN-guided registrations for CTs can be applied to voxel-level dose prediction according to their small V70 change for most lesions. The CNN-guided MR to CT registration still needs to incorporate landmark guidance for smaller change of voxel-level dose estimation.

Lumbar Epidural Anaesthesia versus Caudal Epidural Anaesthesia- Intraoperative and Postoperative Profile in Paediatric Surgical Patients

Introduction: Caudal and lumbar epidural are established techniques of central neuraxial blocks in paediatric anaesthesia. Learning them by landmark guidance is extremely important given the fact that they have a short learning curve and all centres may not be equipped with modern equipment like fluoroscopy and ultrasound. Aim: To compare lumbar epidural anaesthesia with caudal epidural anaesthesia in terms of the ease of needle and catheter insertion, efficacy in providing intraoperative and postoperative analgesia, haemodynamics, patient satisfaction and complications. Materials and Methods: This prospective observational study was done in the Department of Anaesthesiology, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, India between September 2016 and June 2018. Study included 60 patients, aged 2-15 years, of American Society of Anesthesiology (ASA) grade I and II, undergoing elective infraumbilical surgeries. Patients were either administered General Anaesthesia (GA) and 0.2% ropivacaine 0.3 mL/kg through lumbar epidural catheter, or GA and 0.2% ropivacaine 1 mL/kg through caudal epidural catheter. Pain was measured postoperatively using Face, Legs, Activity, Cry, Consolability (FLACC) score and number of rescue topups in the form of tramadol 1.5 mg/kg epidurally were noted. Student’s independent-test was employed for intergroup and, paired t-test and Fisher’s-Exact test was used for intragroup analysis. Results: Out of 60 patients, the mean age±Standard devation (SD) in lumbar technique group and caudal technique group was 8.0000±3.42405 years and 6.5667±2.93238 years, respectively. The age, gender distribution, intraoperative and postoperative vitals (heart rate, mean arterial pressure and oxygen saturation), number of rescue top ups, patient satisfaction were comparable between the two groups. On statistical comparison, needle insertion was easy in 21 patients (vs 13 in lumbar epidural group) and catheter insertion was difficult in 18 (vs 8 in lumbar epidural group) in caudal epidural block compared with lumbar epidural block (p-value=0.037 and 0.010 respectively). No complications were observed in any patient of either group except one patient in group C who had catheter occlusion in the postoperative period. Conclusion: Needle insertion was easy and catheter insertion was difficult in caudal epidural block compared with lumbar epidural block in paediatrics. Both the techniques provided comparable quality of analgesia, stable haemodynamics with minimum complications.

Preprocedural ultrasound assessment of landmarks of paramedian approach for subarachnoid block in geriatric population

Background: Paramedian spinal anesthesia is the preferred anesthetic technique in the elderly. This conventional approach is occasionally challenged by difficulty in identifying landmarks accurately. Neuraxial ultrasound aims to overcome these inaccuracies.Objective: The objective was that the routine use of preprocedural ultrasound assessment of landmarks for paramedian spinal in geriatric population improves the efficacy of spinal anesthesia by reducing the number of attempts and redirections.Materials and Methods: Sixty consenting elderly patients aged 60 year or above, posted for elective surgery under spinal anesthesia, were enrolled in the study. Participants were assigned at random to receive spinal anesthesia by the paramedian approach by either conventional landmark guidance (Group CP) or preprocedural ultrasound-assisted (Group PP) technique.Results: The number of needle redirections was not significant and the success rate at the first attempt with no redirection was higher in the ultrasound compared with the landmark group. However, the mean insertion attempts were indifferent. The preprocedural ultrasound-assisted approach required an insignificantly shorter time for administering spinal anesthesia than the landmark-guided technique (48.87s [67.65] vs. 50.67s [50.19]) [P = 0.90]. The periprocedural pain scores (2.90[2.07] vs. 2.87[1.57]) [P = 0.94] and willingness for a similar future intervention (66.7 vs. 66.7%) were comparable among the groups.Conclusion: The use of preprocedural ultrasonography for paramedian approach to spinal anesthesia is not superior to the conventional landmark guidance in achieving successful dural tap at L3-L4 interspace in elderly adult population and should be limited to a setting with expert operators and selected patients for whom conventional methods may be technically challenging.

Face Reenactment with Generative Landmark Guidance

Face Reenactment with Generative Landmark Guidance

A unified mechanism for innate and learned visual landmark guidance in the insect central complex.

Insects can navigate efficiently in both novel and familiar environments, and this requires flexiblity in how they are guided by sensory cues. A prominent landmark, for example, can elicit strong innate behaviours (attraction or menotaxis) but can also be used, after learning, as a specific directional cue as part of a navigation memory. However, the mechanisms that allow both pathways to co-exist, interact or override each other are largely unknown. Here we propose a model for the behavioural integration of innate and learned guidance based on the neuroanatomy of the central complex (CX), adapted to control landmark guided behaviours. We consider a reward signal provided either by an innate attraction to landmarks or a long-term visual memory in the mushroom bodies (MB) that modulates the formation of a local vector memory in the CX. Using an operant strategy for a simulated agent exploring a simple world containing a single visual cue, we show how the generated short-term memory can support both innate and learned steering behaviour. In addition, we show how this architecture is consistent with the observed effects of unilateral MB lesions in ants that cause a reversion to innate behaviour. We suggest the formation of a directional memory in the CX can be interpreted as transforming rewarding (positive or negative) sensory signals into a mapping of the environment that describes the geometrical attractiveness (or repulsion). We discuss how this scheme might represent an ideal way to combine multisensory information gathered during the exploration of an environment and support optimal cue integration.

Application of Augmented Reality in Percutaneous Procedures-Rhizotomy of the Gasserian Ganglion.

BACKGROUNDPercutaneous rhizotomy of the Gasserian ganglion for trigeminal neuralgia is an effective therapeutic procedure. Yet, landmark-guided cannulation of the foramen ovale is manually challenging and difficult to learn.OBJECTIVETo overcome these limitations, we assessed the feasibility and accuracy of an augmented reality (AR)-guided puncture of the foramen ovale.METHODSA head phantom with soft tissue structures of the facial area was built. A three-dimensional (3D)-dataset of the phantom was generated using a stereotactic planning workstation. An optimal trajectory to the foramen ovale was created and then transferred to an AR headset. A total of 2 neurosurgeons and 2 neuroradiologists independently performed 8 AR-guided and 8 landmark-guided cannulations of the foramen ovale, respectively. For each AR-guided cannulation, the hologram was manually aligned with the phantom. Accuracy of the cannulation was evaluated using the Euclidean distance to the target point as well as the lateral deviation of the achieved trajectory from the planned trajectory at target point level.RESULTSWith the help of AR guidance, a successful cannulation of the foramen ovale was achieved in 90.6% compared to the purely landmark-based method with 18.8%. Euclidean distance and lateral deviation were significantly lower with AR guidance than landmark guidance (P < .01).CONCLUSIONAR greatly improved accuracy of simulated percutaneous rhizotomy of the Gasserian ganglion.

Short-term Efficacy of Ultrasonographic Guidance for Intra-articular Corticosteroid Injection in Hallux Rigidus: A Single-Blind Randomized Controlled Trial

Multiple considerations should be taken before standardizing a clinical procedure such as efficacy, safety, or the cost. The aim of this study was to compare the effects of landmark-guided vs ultrasonography-guided intra-articular injection of corticosteroid into the first metatarsophalangeal joint cavity to reduce pain and dysfunction in patients with hallux rigidus. We carried out a single-blind randomized controlled trial with 2 parallel arms in an outpatient clinic affiliated with a medical university. In total, 50 participants (35 women) with the mean (SD) age of 49.8 (10.3) years were randomly allocated to landmark-guided or ultrasonography-guided groups (each n = 25). Each patient received a single intra-articular injection of 40-mg methylprednisolone plus 1 mL lidocaine into the affected first metatarsophalangeal joint. The primary outcome was joint pain and the secondary outcome was the American Orthopaedic Foot & Ankle Society score. We measured the outcomes at baseline and 2 and 6 weeks after the intervention. Six weeks after the injections, there were no statistically significant differences between the study groups in pain reduction and increase in the American Orthopaedic Foot & Ankle Society scores (P = .131 and .241, respectively). We did not find any complications for the injections in both groups. There were statistically significant changes within each group in pain and the scores for the landmark (P < .001, and P = .007), and ultrasonography groups (both P < .001). Landmark guidance is as effective as ultrasonographic guidance for intra-articular injection in patients with hallux rigidus. A single intra-articular injection of 40 mg methylprednisolone plus 1 mL lidocaine is an efficient and safe therapeutic measure for decreasing joint pain and maintaining its function, at least for 6 weeks. Level I, high-quality prospective randomized study.

RCT of Reduction in Catheter-Related Complications by Using Intracavitary Electrocardiogram-Assisted Guidance in Neonatal PICC Placement

To investigate the effect of intracavitary electrocardiogram (IC-ECG) guidance on peripherally inserted central catheter (PICC) related complications in neonatal patients. A total of 210 neonatal patients were included in the study. They were admitted to the Neonatal Intensive Care Unit, Sichuan Provincial People's Hosptial between January, 2017 and December, 2019 and had PICC lines were placed in their upper limbs. The patients were randomly assigned to the observation group, which had PICC placement through conventional anatomical landmark guidance combined with IC-ECG guidance ( n=105) or to the control group, which had PICC placement through only conventional anatomical landmark guidance ( n=105) for PICC catheter tip positioning. Patient baseline data and data on subsequent catheter-related complications of the two groups were collected and compared. There were no significant difference between the two groups in sex composition, gestational age, postnatal days on the day of PICC placement, duration of PICC placement, disease profile, and the site of puncture ( P>0.05). The observation group showed a significantly lower overall incidence of catheter-related complications (3.8%), compared to that of the control group (21.9%) ( P<0.05). The observation group showed significantly lower incidence of phlebitis and arrhthmia compared to that of the control group ( P<0.05). A combination of anatomical landmark guidance and IC-ECG guidance to assist the placement of PICC decreases catheter-related complications.