Median Axis Research Articles

Carrying angle among young adults of Saudi Arabia and its correlation with demographic characteristics: A cross sectional study.

The angle between the median axes of the forearm and arm is called the carrying angle (CA). Sex differences in CA and its relation to age, height, weight, and BMI are unclear. The aim of the present study was to measure the CA in male and female subjects in the Saudi population and correlate it with the above variables. A digital goniometer was used to measure CA in 181 males and 165 females. Information on age, height, weight, and BMI was also recorded. CA showed differences based on sex, though was independent of age, height, weight, and BMI. Hormonal factors may influence CA and could explain larger CA values in female subjects. CA measurement in specific population groups contributes to the successful management of several pathological conditions of the elbow and aids in the design of elbow orthotics and prosthetics.

Simultaneous correction of leg length discrepancy and angular deformity of the distal femur with retrograde Precice nails: a retrospective analysis of 45 patients.

Magnetically controlled motorized intramedullary lengthening nails (ILNs) can be employed for simultaneous correction of angular deformities of the distal femur and leg length discrepancy. This spares typical complications of external fixators but requires precise preoperative planning and exact intraoperative execution. To date, its results are insufficiently reported. We aimed to elucidate the following questions: (i) Is acute angular deformity correction and gradual femoral lengthening via a retrograde ILN a reliable and precise treatment option? (ii) What are the most common complications of treatment? Acute angular deformity correction and subsequent gradual lengthening of the distal femur with retrograde ILN was retrospectively analyzed in 45 patients (median patient age: 15 years, interquartile range [IQR] 13-19 and median follow-up: 40 months, IQR 31-50). Outcome parameters were accuracy, precision, reliability, bone healing, and complications of treatment. The median distraction was 46 mm (IQR 29-49), median distraction and consolidation index 0.9 mm/day (IQR 0.7-1.0) and 29 days/cm (IQR 24-43), respectively. The median preoperative mechanical axis deviation (MAD) was 30 mm (IQR 23-39) in the varus cohort and -25 mm (IQR -29 to -15) in the valgus cohort and reduced to a mean of 8 mm (standard deviation [SD] 8) and -3 (SD 10), respectively. Accuracy, precision, and reliability of lengthening were 94%, 95% and 96%, respectively. Accuracy and precision of deformity correction were 92% and 89%, respectively. In total, 40/45 of patients achieved distraction with a difference of less than 1 cm from the initial plan and a postoperative MAD ranging from -10 mm to +15 mm. In 13/45 patients unplanned additional surgeries were conducted to achieve treatment goal with nonunion being the most frequent (4/45) and knee subluxation (3/45) the most severe complication. Acute deformity correction and subsequent lengthening of the distal femur with retrograde ILN is a reliable and accurate treatment achieving treatment goal in 89% but unplanned additional surgeries in 29% of patients should be anticipated.

Robust Regression Techniques for Multiple Method Comparison and Transformation.

A generalization of Passing-Bablok regression is proposed for comparing multiple measurement methods simultaneously. Possible applications include assay migration studies or interlaboratory trials. When comparing only two methods, the method boils down to the usual Passing-Bablok estimator. It is close in spirit to reduced major axis regression, which is, however, not robust. To obtain a robust estimator, the major axis is replaced by the (hyper-)spherical median axis. This technique has been applied to compare SARS-CoV-2 serological tests, bilirubin in neonates, and an in vitro diagnostic test using different instruments, sample preparations, and reagent lots. In addition, plots similar to the well-known Bland-Altman plots have been developed to represent the variancestructure.

Anatomy of the Flexor Hallucis Longus and Its Relationship With Hallux Valgus: A Cadaveric Study.

Hallux valgus (HV) is a complex deformity, with many associated risk factors. The flexor hallucis longus (FHL) tendon is a dynamic and potentially deforming force as it bowstrings laterally with HV. We hypothesized that FHL is more laterally inserted in the distal phalanx in cadavers with HV; therefore, it might be also a primary destabilizing force. We aim to compare the FHL distal insertion morphology and its relationship with osseous structures in cadavers with and without HV. Sixteen cadaver specimens, 8 with HV and 8 without (N-HV) were dissected. We evaluated FHL distal morphology in terms of its insertional footprint location and FHL long-axis position in relation to osseous anatomy. Both the HV and N-HV groups displayed a laterally inserted footprint at the distal phalanx, with the HV group exhibiting median lateral translation of the footprint 6% greater than the N-HV group (P < .01). Both groups also demonstrated a laterally displaced position for the FHL long axis. The median FHL long axis for HV vs N-HV specimens 1 cm proximal to the IP joint was 9% more laterally displaced from the midaxis (P < .01), and at 1 cm proximal to the MTP joint was measured to be 15% more laterally displaced from the midaxis (P < .01). FHL demonstrated an eccentric position in terms of insertion and trajectory in both the HV and N-HV groups, with greater lateralization in specimens exhibiting HV deformity. This eccentricity potentially creates a greater deforming force vector contributing to the development of HV. The etiology and progression of HV deformity may include a lateralized insertion of the FHL tendon. Treatment implications remain unknown at this time.

A Proximity-Based Approach for the Identification of Fallen Species of Street Trees during Strong Wind Events in Lisbon

The benefits of urban trees are very well known, but they can fall and cause damage, putting people’s lives at risk. There are few studies on the vulnerability of species to falling. In Lisbon (Portugal), fallen trees have been recorded since 1990 without, however, the identification of the species, knowledge of which is fundamental for improving their management. This study aimed to identify the tree species most vulnerable to falling in Lisbon through a proximity-based approach of known species, since the city has 47,713 inventoried trees, of which only 26,595 (55.7%) were identified. Four criteria were designed to presume the species: (i) the tree must be within 15 m from the street median axis; (ii) at least three individuals within 30 m from the occurrence must belong to the same species; (iii) the surrounding species must be representative in the street (&gt;50%); and (iv) visual identification of avenue medians. Through this approach, considering 3767 fallen trees, it was possible to identify 736 cases, representing 19.5% of all occurrences throughout the studied time and representing 43 different species. Species like Morus nigra L., Tipuana tipu (Benth.) Kuntze, Liriodendron tulipifera L., Prunus cerasifera Ehrh., and Koelreuteria paniculata Laxm. were most vulnerable. Additionally, in 57.7% of cases (425 fallen trees), the wind speed 12-h before the occurrence was greater than 7 m s−1. This research will provide important data for urban planners seeking to maximize the ecosystem services of urban trees.

Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study.

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Глобальное планирование маршрута мобильного робота на основе графовых методов

The problem of global route planning for a mobile robot between two given points in a known area with static obstacles is considered. To solve the problem of constructing a route in an area with a large number of obstacles of complex shape, an integrated approach based on graph theory methods is proposed. It includes the Voronoi diagram, visibility graph and the Dijkstra's algorithm. At the first stage, the study area is represented as a polygonal object, the space outside the object is considered as obstacles. Next, to get a safe distance from obstacles, an internal buffer of the polygonal object is built using the Minkowski difference. Then the vertices of the polygon are compacted, and the Voronoi polygons are constructed from the resulting vertices. The median axis of the polygon is calculated from the Voronoi polygons. Then the Dijkstra's algorithm is applied to calculate the shortest path. The resulting path is used to construct a visibility graph, and the Dijkstra's algorithm is reapplied to the resulting graph. The proposed approach allows to build a route that is optimal in terms of length and distance to obstacles. It significantly reduces the computational complexity of constructing a visibility graph. The approach was implemented in the freely distributed QGIS geographic information system for planning the route of a mobile robot in an aquatic environment. The results of the experiment showed that the Voronoi diagram reduced the number of vertices required to construct the visibility graph by 8.3 times, while the visibility graph improved the path obtained from the Voronoi diagram by 8%. The proposed approach can be used for global planning of routes for mobile robots in various environments.

Space classification for indoor pedestrian navigation with morphological and functional characteristics

AbstractIndoor navigation networks serve as the foundation for indoor pedestrian navigation services. However, current graph‐based topological network models cannot easily represent complex indoor structures in a manner consistent with user behaviour and cognitive patterns, and thus cannot support fine‐grained indoor navigation analysis services. To enhance the rationality of the model, we considered the influences of morphological and functional characteristics of indoor spaces on pedestrian movement and proposed a method for classifying navigation spaces. This method, based on convex space segmentation, defines morphological and functional characteristic functions, classifying indoor navigation spaces as either corridors or open spaces, which suitable for representing as median axis models or visual graphs, respectively. These categories supported the creation of topological network models for route planning analysis. Indoor map experiments confirmed the effectiveness of our method in identifying various types of corridors and open spaces, that addressing the limitations of width‐based parameters, even in complex indoor settings.

Deep learning-based automatic pipeline for 3D needle localization on intra-procedural 3D MRI.

Accurate and rapid needle localization on 3D magnetic resonance imaging (MRI) is critical for MRI-guided percutaneous interventions. The current workflow requires manual needle localization on 3D MRI, which is time-consuming and cumbersome. Automatic methods using 2D deep learning networks for needle segmentation require manual image plane localization, while 3D networks are challenged by the need for sufficient training datasets. This work aimed to develop an automatic deep learning-based pipeline for accurate and rapid 3D needle localization on in vivo intra-procedural 3D MRI using a limited training dataset. The proposed automatic pipeline adopted Shifted Window (Swin) Transformers and employed a coarse-to-fine segmentation strategy: (1) initial 3D needle feature segmentation with 3D Swin UNEt TRansfomer (UNETR); (2) generation of a 2D reformatted image containing the needle feature; (3) fine 2D needle feature segmentation with 2D Swin Transformer and calculation of 3D needle tip position and axis orientation. Pre-training and data augmentation were performed to improve network training. The pipeline was evaluated via cross-validation with 49 in vivo intra-procedural 3D MR images from preclinical pig experiments. The needle tip and axis localization errors were compared with human intra-reader variation using the Wilcoxon signed rank test, with p < 0.05 considered significant. The average end-to-end computational time for the pipeline was 6s per 3D volume. The median Dice scores of the 3D Swin UNETR and 2D Swin Transformer in the pipeline were 0.80 and 0.93, respectively. The median 3D needle tip and axis localization errors were 1.48mm (1.09 pixels) and 0.98°, respectively. Needle tip localization errors were significantly smaller than human intra-reader variation (median 1.70mm; p < 0.01). The proposed automatic pipeline achieved rapid pixel-level 3D needle localization on intra-procedural 3D MRI without requiring a large 3D training dataset and has the potential to assist MRI-guided percutaneous interventions.

Combination of intrahepatic TARE and extrahepatic TACE to treat HCC patients with extrahepatic artery supply: A case series

PurposeThe aim of this study was to report the safety and tumor response rate of combined transarterial radioembolization (TARE) through the intrahepatic arteries and transarterial chemoembolization (TACE) through the extrahepatic feeding arteries (EHFA) in patients with hepatocellular carcinoma (HCC). MethodsPatients with HCC, who had both intrahepatic and extrahepatic arterial supply visible on preinterventional multiphase CT and were treated between 2016 and 2021 with a combination of TACE and TARE on the same nodule, were retrospectively included. Epidemiological, clinical, biological, and radiological characteristics were recorded. Safety and tumor response were assessed at 6 months. ResultsNine patients (8 men, median age 62 years [IQR: 54–72 years]) were included. Seven patients had previous treatments on the target nodule (TARE: 5; TACE: 2). The median longest axis (LA) of the lesion was 70 mm (IQR: 60–79 mm). Three patients had portal vein invasion (VP3). The EHFA originated from the right diaphragmatic artery (n = 6), the right adrenal artery (n = 2), and the left gastric artery (n = 1). The LA of the tumor portion treated with TACE was 47 mm (range: 35–64 mm). The ratio between the LA of the entire lesion and the LA treated with TACE was 1.44 (range: 1.27–1.7). One major complication occurred: acute on chronic liver failure. Median follow-up was 23 months (range: 16–29 months). Seven patients underwent further treatment: on the same lesion (n = 2), on newly appeared nodules (n = 2), and systemic treatment (n = 3). At 6-month follow-up, seven patients showed a local objective response. Time-to-progression was 13 (3.5–19) months. ConclusionThe combination of TARE and extrahepatic TACE for HCC with both intrahepatic and extrahepatic arterial supplies seems feasible and safe. Further studies are needed to validate the effectiveness of these preliminary results.

Numerical analysis and evaluation of a semi-heavy guardrail system

The continuous increase in traffic accidents, following the rise in the number of vehicles in traffic and their speed, requires the development of research on the design of active and passive safety systems. This research mainly aims to compare the performance of commonly used passive safety systems (semi-heavy W-beam guardrails) mounted on roadside and pedestrian bridges to protect vehicles and pedestrians. It is intended to reduce the deformations of the vehicle upon impact with the protective device mounted between the roadside and the pedestrian area for the protection of the vehicle occupants; reduce the parapet working width for the pedestrian’s safety; and maintain the vehicle’s trajectory from the moment of impact to the final movement, between the guardrail and the median axis of the road, to ensure the protection of other road users. A CAD model of the vehicle-guardrail scenario was developed to achieve these objectives. Load simulation cases are performed using the finite element method according to the European standards SR EN 1317 for impact tests of vehicles - TB 42, recommended for semi-heavy guardrails.

The Potential of Iron Oxide Nanoparticle-Enhanced MRI at 7 T Compared With 3 T for Detecting Small Suspicious Lymph Nodes in Patients With Prostate Cancer.

Accurate detection of lymph node (LN) metastases in prostate cancer (PCa) is a challenging but crucial step for disease staging. Ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) enables distinction between healthy LNs and nodes suspicious for harboring metastases. When combined with MRI at an ultra-high magnetic field, an unprecedented spatial resolution can be exploited to visualize these LNs. The aim of this study was to explore USPIO-enhanced MRI at 7 T in comparison to 3 T for the detection of small suspicious LNs in the same cohort of patients with PCa. Twenty PCa patients with high-risk primary or recurrent disease were referred to our hospital for an investigational USPIO-enhanced 3 T MRI examination with ferumoxtran-10. With consent, they underwent a 7 T MRI on the same day. Three-dimensional anatomical and T2*-weighted images of both examinations were evaluated blinded, with an interval, by 2 readers who annotated LNs suspicious for metastases. Number, size, and level of suspicion (LoS) of LNs were paired within patients and compared between field strengths. At 7 T, both readers annotated significantly more LNs compared with 3 T (474 and 284 vs 344 and 162), with 116 suspicious LNs on 7 T (range, 1-34 per patient) and 79 suspicious LNs on 3 T (range, 1-14 per patient) in 17 patients. For suspicious LNs, the median short axis diameter was 2.6 mm on 7 T (1.3-9.5 mm) and 2.8 mm for 3 T (1.7-10.4 mm, P = 0.05), with large overlap in short axis of annotated LNs between LoS groups. At 7 T, significantly more suspicious LNs had a short axis <2.5 mm compared with 3 T (44% vs 27%). Magnetic resonance imaging at 7 T provided better image quality and structure delineation and a higher LoS score for suspicious nodes. In the same cohort of patients with PCa, more and more small LNs were detected on 7 T USPIO-enhanced MRI compared with 3 T MRI. Suspicious LNs are generally very small, and increased nodal size was not a good indication of suspicion for the presence of metastases. The high spatial resolution of USPIO-enhanced MRI at 7 T improves structure delineation and the visibility of very small suspicious LNs, potentially expanding the in vivo detection limits of pelvic LN metastases in PCa patients.

ACME2: An extended toolbox for automated cirque metrics extraction

With the availability of improved digital elevation models (DEMs) of global coverage, the morphological analysis of large populations of glacial cirques is possible, and can be used to derive important palaeoclimate and environmental information related to the distribution and history of former glaciers. In 2017, an ArcGIS toolbox, ACME (Automated Cirque Metrics Extraction), was developed to derive 16 cirque metrics based on input cirque outlines, threshold midpoints and DEMs. ACME has been widely used in cirque morphological analysis and regional comparisons. This paper presents a revised and extended toolbox, ACME2. This extended toolbox includes new functions to automatically derive cirque threshold midpoints (cirque foci) and 49 morphometric and locational variables, with attributes related to cirque location, size, shape, altitude, slope, and aspect, including variables related to the median axis, as well as 3 input metadata attributes. ACME2 also improves the methods for calculation of the hypsometric maximum and integral, and implements a new method for plan closure to be more consistent with the original definition. All ACME2 tools are coded in Python and can be imported into ArcGIS with user-friendly interfaces. Comparisons for 155 cirques in the English Lake District and 51 in the Shulaps Range, British Columbia, indicate consistency between the ACME2-derived and manually derived metrics, with most correlations r > 0.90: none <0.70. ACME2 provides more cirque metrics and automates the whole calculation sequence with cirque outlines and DEMs. Its comprehensive approach facilitates understanding of cirque form and development in all its variety.

Multiples among B stars in the Scorpius-Centaurus association

Context. The frequency, semi-major axis, and mass distribution of stellar companions likely depend on the mass of the primaries and on the environment where the stars form. These properties are very different for early- and late-type stars. However, data are largely incomplete, even for the closest environments to the Sun, preventing a cleaner view of the problem. Aims. This paper provides basic information about the properties of companions to B stars in the Scorpius-Centaurus association (age ∼ 15 Myr); this is the closest association containing a large population of 181 B-stars. Methods. We gathered available data combining high contrast imaging samples from BEAST, SHINE, and previous surveys with evidence of companions from Gaia (both through direct detection and astrometry), from eclipsing binaries, and from spectroscopy. We evaluated the completeness of the binary search and estimated the mass and semi-major axis for all detected companions. These data provide a complete sample of stellar secondaries (extending well in the substellar regime) for separation&gt; 3 au, and they are highly informative as to closer companions. Results. We found evidence for 200 companions around 181 stars. We did not find evidence for companions for only 43 (23.8 ± 3.6%) of the targets, with the fraction being as low as 15.2 ± 4.1% for stars with MA &gt; 3.5 M⊙ while it is 31.5 ± 5.9% for lower-mass stars. This confirms earlier findings for a clear trend of a binary fraction with stellar mass. The median semi-major axis of the orbits of the companions is smaller for B than in A stars, confirming a turn-over previously found for OB stars. The mass distribution of the very wide (a &gt; 1000 au) and closer companions is different. Very few companions of massive stars MA &gt; 5.0 M⊙ have a mass below solar and even fewer are M stars with a semi-major axis &lt; 1000 au. However, the scarcity of low-mass companions extends throughout the whole sample. Period and mass ratio distributions are different for early B stars (up to B7 spectral type) and stars of a later spectral type: most early B stars are in compact systems with massive secondaries, while less massive stars are mainly in wider systems with a larger spread in mass ratios. We derived log-normal fits to the distribution of the semi-major axis and mass ratios for low and high-mass B stars; these relations suggest that it is not probable that the planets and brown dwarf (BD) companions to b Cen and μ2 Sco are extreme cases in the distribution of stellar companions. Conclusions. We interpret our results as the formation of secondaries with a semi-major axis &lt; 1000 au (about 80% of the total) by fragmentation of the disk of the primary and selective mass accretion on the secondaries. The formation of secondaries within the disk of primaries in close binaries has been proposed by many others before; it unifies the scenarios for formation of close binaries with that of substellar companions that also form within the primary disk, though on a different timescale. We also find that the observed trends with primary mass may be explained by a more prolonged phase of accretion episodes on the disk and by a more effective inward migration. Finally, in the Appendices we describe the detection of twelve new stellar companions from the BEAST survey and of a new BD companion at 9.599 arcsec from HIP 74752 using Gaia data, and we discuss the cases of possible BD and low-mass stellar companions to HIP 59173, HIP 62058, and HIP 64053.

Prostate-specific membrane antigen radioguided surgery with negative histopathology: an in-depth analysis

PurposeTo identify reasons for negative histopathology of specimens from prostate-specific membrane antigen (PSMA) radioguided surgery (PSMA-RGS) in recurrent prostate cancer (PCa) after prostatectomy.MethodsOf 302 patients who underwent PSMA-RGS, 17 (5.6%) demonstrated a negative histopathology. Preoperative data, PSMA PET, PSMA SPECT, and follow-up information were analyzed retrospectively to differentiate true/false positive (TP/FP) from true/false negative (TN/FN) lesions.ResultsThe median prostate-specific antigen at PET was 0.4 ng/ml (interquartile range [IQR] 0.3–1.2). Twenty-five index lesions (median short axis 7 mm, IQR 5–8; median long-axis 12 mm, IQR 8–17) had a median SUVmax of 4 (IQR 2.6–6; median PSMA expression score 1, IQR 1–1). Six lesions were TP, twelve were FP, one was TN, and six remained unclear. All TP lesions were in the prostatic fossa or adjacent to the internal iliac arteries. Three suspected local recurrences were FP. All FP lymph nodes were located at the distal external iliac arteries or outside the pelvis. A low PSMA-expressing TN node was identified next to a common iliac artery. Unclear lesions were located next to the external iliac arteries or outside the pelvis.ConclusionIn most cases with a negative histopathology from PSMA-RGS, lesions were FP on PSMA PET. Unspecific uptake should be considered in low PSMA-expressing lymph nodes at the distal external iliac arteries or outside the pelvis, especially if no PSMA-positive lymph nodes closer to the prostatic fossa are evident. Rarely, true positive metastases were missed by surgery or histopathology.

A rare case of multifocal chordoma involving the lower clivus and multiple spine levels: illustrative case.

Chordomas are rare bone tumors originating from notochord remnants with a predilection for the median axis of the body, primarily in the sacrococcygeal spine, skull base, and cervical spine. This paper presents the first reported case of simultaneous multilevel chordomas with various enhancements. A 40-year-old woman presented with right-sided otalgia, headache, nasal obstruction, and facial pressure. The patient's head and spinal magnetic resonance imaging (MRI) demonstrated a midline lesion in the clivus, C2, and T1-5 spinal levels. All lesions were T1 isointense and T2 hyperintense, consistent with chordoma. Interestingly, the clivus lesion was enhancing, whereas the C2 lesion was only slightly enhancing, and the rest of the lesions showed no enhancement. The patient underwent endoscopic endonasal transclival approach surgery for the clival lesion, followed by radiation to the surgical bed and the C2 lesion. The remaining lesions were monitored. Follow-up imaging showed stable disease in the C2 lesion and other lower lesions. The patient's severe pain in the posterior cervical spine was managed with cervical fusion, pain management, and physical therapy. This case underscores the importance of comprehensive spinal MRI in patients with chordomas, as multiple concurrent primaries may be present. The article summarizes the fundamental distinctions between ecchordosis physaliphora and chordoma and casts doubt on the capacity to always differentiate them.

Value of frontal QRS axis for risk stratification of individuals with prolonged PR interval.

There is ongoing controversy regarding the prognostic value of PR prolongation among individuals free of cardiovascular diseases. It is necessary to risk-stratify this population according to other electrocardiographic parameters. This study is based on the Third National Health and Nutrition Examination Survey. Cox proportional hazard models were constructed and Kaplan-Meier method was used. A total of 6188 participants (58.1 ± 13.1 years; 55% women) were included. The median frontal QRS axis of the entire study population was 37° (IQR: 11-60°). PR prolongation was present in 7.6% of the participants, of whom 61.2% had QRS axis ≤37°. In a multivariable-adjusted model, mortality risk was highest in the group with concomitant prolonged PR interval and QRS axis ≤37° (hazard ratio [HR]: 1.20; 95% confidence interval [CI]: 1.04-1.39). In models with similar adjustment where population were reclassified depending on PR prolongation and QRS axis, prolonged PR interval and QRS axis ≤37° was still associated with increased risk of mortality (HR: 1.18; 95% CI: 1.03-1.36) compared with normal PR interval. QRS axis is an important factor for risk stratification in population with PR prolongation. The extent to which this population with PR prolongation and QRS axis ≤37° is at higher risk of death compared with the population without PR prolongation.

Acute Retropharyngeal and Parapharyngeal Abscesses: A Case Series.

The purpose of this study was to evaluate the diagnosis circumstances, predisposing factors, investigations, and therapeutic management of retropharyngeal and parapharyngeal abscesses. A retrospective chart review of patients diagnosed with retropharyngeal or parapharyngeal abscess from 2001 to 2021 was performed. Epidemiological characteristics, clinical signs, investigations, medical treatment, and surgical interventions were analyzed for each patient. A total of 30 patients with retropharyngeal or parapharyngeal abscess were identified. Computed tomography was performed in all cases, and magnetic resonance imaging was performed in three cases. Twelve patients had a "pure" retropharyngeal abscess, nine patients had a prestyloid abscess, one patient had a prestyloid abscess associated with a peritonsillar abscess, three patients had a retrostyloid abscess, and five patients had a prestyloid abscess associated with a retropharyngeal abscess or a retrostyloid abscess. The median long axis of the abscess was 42cm. All patients received intravenous antibiotics for a median period of 8days [4-30]. Seventeen patients required surgical trans-cervical drainage. Other patients underwent transoral or transnasal drainage. The pus culture revealed no growth in six cases, streptococcus (four cases), methicillin-sensitive Staphylococcus aureus (two cases), Klebsiella (two cases), Enterobacter (one case), Fungi (two cases), and Mycobacterium tuberculosis (a twelve-year-old boy). It was not documented in twelve cases. Histological examination revealed caseofollicular tuberculosis in a 53-year-old man. In 25 patients, no adverse events were observed during follow-up. Five patients had an unfavorable outcome. We have found an increase in the incidence of these infections in recent years. Computed tomography is the best imaging examination for the diagnosis and follow-up of retropharyngeal and parapharyngeal abscess. Early drainage and antimicrobial therapy are essential for rapid recovery and prevention of complications of these abscesses.

Electrocardiographic patterns of ventricular pre-excitation in dogs with right-sided accessory pathways.

The aim of the study was to describe the electrocardiographic features of ventricular pre-excitation (VPE) patterns characterized by the presence of delta (δ) wave, short P-δQRS interval, wide δQRS complexes in dogs with right-sided accessory pathways. Twenty-six dogs with a confirmed accessory pathways (AP) via electrophysiological mapping were included. All dogs underwent a complete physical examination, 12-lead ECG, thoracic radiography, echocardiographic examination and electrophysiologic mapping. The AP were located in the following regions: right anterior, right posteroseptal, right posterior. The following parameters were determined: P-δQRS interval, δQRS duration, δQRS axis, δQRS morphology, δ-wave polarity, Q-wave, R-wave, R'-wave, S-wave amplitude, and R/S ratio. In lead II, the median δQRS complex duration was 82.4 (IQR 7.2) and the median P-δQRS interval duration was 54.6 (IQR 4.2) msec. The median δQRS complex axis in the frontal plane was: + 68° (IQR 52.5) for right anterior APs, - 24 ° (IQR 24) for right postero-septal APs, - 43.5 ° (IQR 27.25) for right posterior APs (P = 0.007). In lead II, the polarity of the δ wave was positive in 5/5 right anterior APs and negative in 7/11 postero-septal APs and 8/10 in right posterior APs. In precordial leads of all dogs, R/S was ≤ 1 in V1 and > 1 in all leads from V2 to V6. Surface electrocardiogram can be used to distinguish right anterior APs from right posterior and right postero-septal ahead of an invasive electrophysiological study.

Reopenable clip-over-the-line method for closing large mucosal defects following gastric endoscopic submucosal dissection: Prospective feasibility study.

Large mucosal defects following gastric endoscopic submucosal dissection (ESD) cause postoperative bleeding. To address this limitation and ensure closure of large mucosal defects, we developed the reopenable clip-over-the-line method (ROLM) using a reopenable clip and nylon line. The purpose of this study was to evaluate the feasibility of the ROLM for closure of large mucosal defects following gastric ESD in a prospective, consecutive series of cases. We performed the ROLM on 50 consecutive patients with gastric mucosal defects at the Ise Red Cross Hospital and Mie Prefectural Shima Hospital. The time to complete the ROLM, numbers of clips and lines required, size of defect, and closure success rate were measured, and postoperative adverse events were recorded. In all, 50 lesions were included in this study period between July 2021 and March 2022. The success rates of defect closure and defect closure without submucosal dead space of the ROLM were both 100% (50/50), with a median ROLM time of 30 (range, 14-35) min and a median resected specimen major axis of 45 (range, 31-73) mm. The median number of reopenable clips used was 31 (range, 10-93). Following gastric ESD, two cases of post-ESD bleeding were observed during the follow-up periods. Our results suggest that ROLM is a feasible strategy for complete closure of mucosal defects post-ESD without submucosal dead space. Future comparative studies with post-ESD bleeding rate as the main outcome are desirable to evaluate the efficacy of ROLM.