Level Of Bifurcation Research Articles

Anatomical Variations of the Bifurcation Levels of the Common Carotid Artery and Superior Thyroid Artery.

Variations in the carotid arterial system significantly impact atherosclerosis's clinical and surgical management, which predominantly occurs at arterial bifurcations. This study aimed at evaluating anatomical variations in the bifurcation levels of the common carotid artery (CCA) and the superior thyroidartery (STA), emphasizing clinical relevance. This was an observational cross-sectional study conducted in June 2021 using 32 embalmed cadavers of adult age from medical schools in Khartoum, Sudan. Sixty-four carotids were examined, noting the levels of CCA bifurcation and STA origin, and their symmetry across both sides of the body. Results: Among the cadavers studied, CCA bifurcation most commonly occurred at the superior border of the thyroid cartilage (46.9%), followed by the body of the hyoid bone (40.1%). The STA predominantly originated from the external carotid artery (ECA) (65.6%). Conclusion: No significant correlation was found between the bifurcation levels of the CCA and the origins of the STA. Bilateral symmetry in the bifurcation of the CCA and the origin of the STA was observed in most cases. The study highlights notable variations in the anatomy of the carotid arteries. These findings suggest that pre-surgical imaging and careful planning are crucial to accommodate anatomical diversities.

Carina: A major determinant in the pathophysiology and treatment of coronary bifurcation lesions.

Over the last decade, several in vivo and computational investigations have significantly advanced our understanding of the pathophysiology of coronary bifurcations, contributing to the enhancement of their percutaneous revascularization. The carina of the coronary bifurcations plays a substantial role in generating their main hemodynamic features, including distinctive flow patterns with secondary flows and specific shear stress patterns. These factors play a pivotal role in determining the susceptibility, development, and progression of atherosclerosis. The underlying pathophysiological mechanisms of atherosclerosis in coronary bifurcations are complex and multifactorial. Understanding these mechanisms is fundamental to comprehending lesions at the bifurcation level and informing future treatment strategies. This review aims to present the currently available data regarding the pathophysiological and prognostic role of the carina in coronary bifurcations, offering an interpretation of these findings from the perspective of interventional cardiologists, providing valuable insights for their clinical practice.

Ratio of pulmonary artery diameter to ascending aortic diameter and its association with right ventricular failure after left ventricular assist device implantation

BackgroundSeveral invasive hemodynamic parameters help predict right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation. However, prediction using non-invasive parameters alone has not been established. The ratio of the diameters of the pulmonary artery (PAD) to those of the ascending aorta (AoD) may indicate past hemodynamic load and cardiac dysfunction. We aimed to investigate a predictive model for RVF after LVAD implantation using non-invasive parameters including PAD/AoD ratio. MethodsWe studied 141 patients who underwent primary LVAD implantation and 117 healthy individuals with computed tomography (CT) data. RVF was defined as the need for a subsequent right ventricular assist device or intravenous inotrope administration for more than 30 days after LVAD implantation. The PAD/AoD ratio was measured at the level of the pulmonary artery bifurcation on the CT transaxial slices. ResultsRVF was observed in 29 patients. The correlation between PAD and AoD differed among healthy individuals, patients with and without RVF. Patients with RVF had higher total bilirubin and log brain natriuretic peptide (BNP) levels, a lower left ventricular end-diastolic diameter (LVDd) index, and a higher PAD/AoD ratio than those without RVF. Decision tree analysis indicated that the subgroup with a high PAD/AoD ratio (≥1.09) and a small LVDd index (<35.4 mm/m2) showed the highest probability of RVF (100 %), while the subgroup with a low PAD/AoD ratio (<1.09) and low log BNP (<2.79) showed the lowest probability of RVF (1 %). ConclusionCombining non-invasive parameters with the PAD/AoD ratio can predict RVF with high accuracy.

Management of gunshot injury to the abdominal aorta and inferior vena cava: a case report of a combat patient wounded in the Russo-Ukrainian war

BackgroundRusso-Ukrainian war is associated with severe traumas, including injuries to the major vessels. Penetrating aortic injury remains one of the most difficult injuries; the mortality rate is 90–100% in case of gunshot wounds, associated with frequent lethal outcomes due to uncontrolled bleeding. Of the three main abdominal veins, the inferior vena cava (IVC) is the most frequently damaged, which is required quick and appropriate surgical decisions to be made. Little is known about the management of gunshot injuries to such major vessels as the aorta and IVC. It is also worth mentioning about the importance to share our practical experience from the ongoing war for better understanding and future considerations by war surgeons of the vascular trauma management. The aim of the study was to demonstrate the specific features of the diagnosis and management of a gunshot shrapnel blind penetrating wound to the abdomen with injury to the aortic bifurcation level and the infrarenal section of the inferior vena cava.Case presentationA 44-year-old male soldier of the Armed Forces of Ukraine received a gunshot injury to the abdomen from a mortars’ explosive shelling. The patient was evacuated to the Forward Surgical Team (Role 1) and received primary surgical treatment within one hour after the injury according to the “golden hour” principle. Then, evacuated was performed to the Role 3 hospital in Kharkiv. At the Role 3 hospital, the patient underwent second-look surgery as well as damage control surgery. At revision, no active bleeding was observed, and the surgical pads (packed previously by the Forward Surgical Team) were removed. Further revision showed a metal projectile within the aortic wall at the level of aortic bifurcation and wall defects were also detected for inferior vena cava. This metal projectile was removed by using the multifunctional surgical magnetic tool followed by suturing of the aortic wall defect as well as defects of the inferior vena cava.ConclusionsApplication of Damage Control Surgery is a useful approach in the management of severe vascular injury as well as useful to stop abdominal contamination by intestinal contents. The application of a surgical magnetic tool for the searching and removal of ferromagnetic foreign bodies reduces operative trauma and reduces the time for identification of foreign bodies.

214. THORACIC CAVITY/ CAGE RATIO IS PREDICTOR FOR SURGICAL DIFFICULTY OF MINIMALLY INVASIVE ESOPHAGECTOMY

Abstract Background Esophagectomy for esophageal cancer is highly invasive surgery. Minimally invasive esophagectomy (MIE) was introduced as a less invasive surgery, and conventional MIE (C-MIE) is being increasingly performed worldwide. Recently, robot-assisted MIE (RAMIE) was developed with the aim of further minimization of invasiveness, and is expected to spread in the future. When performing MIE, we sometimes experienced difficult cases. In this study, we aimed to clarify the factors related to surgical difficulty of MIE. Methods We evaluated 362 patients who underwent MIE (285 C-MIEs and 77 RAMIEs) for esophageal squamous cell carcinoma between April 2010 and February 2023. We used computed tomography to evaluate the occipitofrontal diameter of thoracic cavity and cage at brachiocephalic vein (BV), tracheal bifurcation (TB) and inferior right pulmonary vein (IRPV) levels, respectively. We calculated the thoracic cavity/cage ratio (TRRC) at each level. The cut-off values of TCCR at each level for thoracic procedure time were calculated using the receiver operating characteristic. Furthermore, total score consisted of four degrees (0,1,2,3) by the TCCR at three levels was calculated. We assessed clinicopathological and anatomical factors and determined the independent factors influencing the thoracic procedural time as parameter of difficulty in MIE. Results We divided the patients into C-MIE group and RAMIE group. Patients in each group were divided into two cohorts according to median thoracic procedure time (C-MIE: 307 and RAMIE: 409 minutes, respectively). In the C-MIE group, univariate analysis demonstrated that sex, body mass index (BMI), and the TCCR at BV, TB and IRPV levels were correlated with thoracic procedure time. The total TRRC score was also correlated with thoracic procedure time in univariate analysis. Next, multivariate analysis was done using sex, BMI, and the total TCCR score. Multivariate analyses demonstrated that BMI (p = 0.0005) and the total score (p = 0.0069) were independent factors for thoracic procedure time. In the RAMIE group, univariate analysis demonstrated that BMI and the TCCR at BV and TB levels were correlated with thoracic procedure time. Multivariate analyses demonstrated that the TCCR at TB level (p = 0.0187) was only independent factor for thoracic procedure time. Conclusions The TCCR and the total score based on it could be useful in assessing surgical difficulty of both C-MIE and RAMIE. C-MIE was affected by the diameter at all levels of the thoracic cavity due to restricted mobilities of thoracoscopic instruments. On the other hand, RAMIE’s articulated forceps prevent it from being affected by entire thoracic cavity. Consequently, only the TCCR at TB level, which is one of the most less flexible field, affects the difficulty in RAMIE.

Increased Aortic Stiffness With Acute Exercise in Heart Failure: Assessment by Cardiovascular Magnetic Resonance

This study aimed to investigate the acute changes in proximal aortic distensibility, a measure of aortic stiffness, induced by acute exercise in participants with and without heart failure (HF). Participants with HF (n = 24) and without HF (n = 26) underwent cardiovascular magnetic resonance (CMR) (1.5 T) imaging at rest and after submaximal supine bicycle ergometry. The participants were further categorized into HF with reduced ejection fraction (HFrEF) (n = 14) and HF with preserved ejection fraction (n = 10) based on the left ventricular ejection fraction. At rest and immediately after exercise, cine CMR images of the cross-sectional ascending and descending aorta at the pulmonary artery bifurcation level were obtained to determine aortic distensibility (AoD), with lower AoD indicating greater aortic stiffness. Differences in means of values at rest and before and after exercise were compared using the nonparametric Wilcoxon sign test. There was no significant difference in AoD at rest between subjects with HF and controls. However, immediately after exercise, participants with HF but not controls exhibited a significant reduction in AoD, indicating higher aortic stiffness related to exercise (median [interquartile range] for the ascending aorta: 3.16 (1.26) × 10-3 mm Hg-1 to 2.39 (1.57) × 10-3 mm Hg-1 and the descending aorta: 4.19 (2.58) × 10-3 mm Hg-1 to 2.96 (1.79) × 10-3 mm Hg-1) (both p = 0.023). This decrease was particularly observed in participants with HFrEF but not in those with HF with preserved ejection fraction. Exercise-induced aortic stiffness, detectable by noninvasive CMR, may contribute to unfavorable ventricular-vascular interactions during exercise in participants with HF, especially HFrEF.

A cadaveric study on superior hypogastric plexuses

Introduction: The superior hypogastric plexus (SHP) is found around the level of aortic bifurcation. It is important in surgical procedures in the pelvis.Methods: Ten (5; M &amp; 5; F) fresh intact adult human cadavers were dissected. Following the initial dissection, all of them were further sectioned sagittal in the midline and separated in to half pelvises, and assessed. The study was carried out in the Department of Anatomy, Faculty of medicine Ragama, Sri Lanka from 2022 to 2024. The ethical clearance was obtained.Results: In all specimens, left connecting fibers from the inferior mesenteric plexuses (IMA) crossed the left common iliac artery and joining to the superior hypogastric plexuses. In 80%, right connecting nerve fibers from the inferior mesenteric plexuses crossed the right common iliac artery and joined the superior hypogastric plexus (SHP). Eighty percent of the specimens had, well-defined nerve strands, whereas 20% contained a delicate and irregular meshwork. In all of the specimens, the median root, or a nerve root from abdominal aortic plexus from the IMA were present. In 80% specimens, the SHP was located between the aortic bifurcation and the sacral promontory. In 20%, it extended across the pelvic brim and ended on the body of the S1 vertebra.Conclusion: The majority of the SHP were located below the aortic bifurcation and had well-defined nerve strands, rest traversed the pelvic brim and terminated on the body of the S1 vertebra. Further larger sample studies are recommended.

Comprehensive Analysis of Mandibular First Molar Root and Canal Morphology in Saudi Patients Using Cone Beam Computed Tomography (CBCT).

BACKGROUND The goal of conventional endodontic therapy is to clean the root canal system thoroughly, restore tooth function, and prevent re-infection. Success depends on understanding root canal morphology, resolving apical periodontitis, and using proper techniques. Studies highlight variations in root canal anatomy, with cone-beam computed tomography (CBCT) being crucial for accurate diagnosis despite its high cost and limited availability. MATERIAL AND METHODS This retrospective study reviewed CBCT images of 1820 (907 male, 913 female) patients aged 18 to 78 years. Analysis included 2081 mandibular first molars for variations in root and canal morphology and right- and left-side symmetry. Inter-orifice distance was measured, along with distance from the cementoenamel junction (CEJ) to the level of canal bifurcation. RESULTS In this study, 96.01% of teeth had 2 roots and 3.89% had 3 roots. The percentages of canal configuration were 77.70% for 3 canals, 21.58% for 4 canals, 0.67% for 2 canals, and 0.05% for 1 canal. The inter-orifice distance was 2.07 mm for 2 canals in 1 root and 2.86 mm for 2 canals in separate distal roots. Distance from the CEJ to canal bifurcation varied significantly between 2 canals within 1 distal root (3.35 mm), 2 canals in separate distal roots (1.60 mm), as well as between distal (3.35 mm) and mesial roots (1.10 mm). CONCLUSIONS In mandibular first molars, only 3.89% have additional distolingual roots. Sex and ethnicity showed no influence on number of roots and canals. Distal canals showed a deeper bifurcation and greater inter-orifice distance than did mesial canals.

Unraveling Renal Arteries Morphogenesis from Tridimensional Human Embryos Reconstruction

During human morphogenesis, the definitive kidneys derive from the metanephros during Carnegie Stage 14 to 23. The pronephros and the mesonephros develop previously and successively to finally lead to the formation of the urinary tract. Renal vascularization, first described in 1912 by Félix using a "ladder theory" model, is highly variable and current available morphogenesis descriptions do not explain all reported anatomical variations. The aim of this work was to study the morphogenesis of the human metanephros and its vascularization by three-dimensional reconstructions of human embryos. Histological sections of 23 human embryos from the Carnegie Collection and 5 human embryos from the French collection (Carnegie stages 14 to 23) were completely digitalized and reconstructed in three dimensions using specific softwares and then analyzed by descriptive method using manual annotation. In all studied embryos, the mesonephric arteries did not reach the metanephros irrespective to the position of the metanephros during its cranial ascent. Before the end of the cranial metanephros migration (15 embryos), at the level of the aorto-iliac bifurcation, a "primitive" vascularization was shown in 9 of them. The renal artery originated from the primitive iliac arteries for 8 embryos and from the inferior mesenteric artery in one embryo. Further, a capillary cluster emerging from the lateral wall of the aorta and extending toward the metanephros was found in 2 embryos (Carnegie stages 21 and 22). This may correspond to a phenomenon of neoangiogenesis responsible of the definitive renal artery. The present study reported the morphogenesis of human renal arteries between Carnegie stages 14 and 23 using an original method of tridimensional computerized reconstructions of historical human embryos. Some original findings, in contradiction with the original Felix's description, may explain the most frequently reported anatomical variations.

Variations in origin level of superior mesenteric artery, inferior mesenteric artery, and coeliac trunk in Indian population.

The abdominal aorta is a continuation of the thoracic aorta and gives off the coeliac trunk, superior mesenteric artery, and inferior mesenteric artery. The focus of our study is to evaluate variations in the origin level in the coeliac trunk, superior mesenteric artery, inferior mesenteric artery, and aortic bifurcation in the Indian population and compare with various demographics. The study was retrospective and the local ethics committee approval was taken before starting it. Three hundred patients who were more than 18 years of age and required contrast-enhanced CT studies were included in this. The vertebral origin level of the arteries from the abdominal aorta and aortic bifurcation level was analysed. The most common origin level of the coeliac trunk for both males and females was T12-L1 disc level. The most common origin level of the superior mesenteric artery was L1 upper level. The most common origin level of the inferior mesenteric artery was L3 upper level. The most common level of aortic bifurcation was L4 middle level. There was no statistical difference between the origin of any arteries in males and females in the Indian population. As per our study of the Indian population and the published literature, it is realized that there are significant variations in the origins of the coeliac trunk, superior mesenteric artery, inferior mesenteric artery, and abdominal aorta bifurcation in different populations. This study elaborates on potential anatomical variations in the Indian population, particularly the Mumbai city population. Also, our study compares it to different countries' data and their results in variations found in abdominal aorta branches.

The vertical topography of the carotid bifurcation – original study and review

PurposeThe vertical level of carotid bifurcation (CB) is commonly indicated at the superior margin of the thyroid cartilage. Few studies observed the CB vertical topography. It was aimed at studying the vertical location of the CB as referred to vertebral and anterior cervical landmarks.MethodsAn archived lot of 147 computed tomography angiograms was documented for the vertical level of CB referred to vertebral and anterior cervical landmarks. The topography of the CB in relation to anterior landmarks was classified into seven types: (1) at the superior margin of the thyroid cartilage; (2) between the hyoid and the thyroid cartilage; (3) at the hyoid level; (4) between the hyoid and mandible; (5) subgonial or supragonial CB; (6) lower cervical level; (7) intrathoracic.ResultsThe most common locations of CB were at C3 (27.21%), C3/C4 (26.19%) and C4 (25.51%). Bilateral symmetry of CB was found in 51.7%, except for C2 and C5/C6. Type 7 was not found, type 3 occurred in 39.12%, type 2 in 24.49%, type 1 in 13.95%, type 4 in 13.61%, type 5 in 6.12%, and type 6 in 2.72% (294 CBs). Bilateral symmetry of anterior types was found in 59.86%. Statistically significant correlations were found between sex and both left and right types and vertebral levels of CB.ConclusionsThe vertical topography of the CB is highly variable and has sex-related specificity. This detail should be included in the teaching of anatomy. Surgeons and interventionists should better document the carotid anatomy on a case-by-case basis.

Defining Surgical Difficulty During Open Right Lobe Donor Hepatectomy and its Prediction Using Preoperative Donor Computed Tomography Morphometry

BackgroundThere is no accepted way to define difficult donor hepatectomy (DiffDH) during open right living donor hepatectomy (ORLDH). There are also no studies exploring association between DiffDH and early donor outcomes or reliable pre-operative predictors of DiffDH. MethodsConsecutive ORLDH performed over 18 months at a single center were included. Intra-operative parameters were used to develop an objective definition of DiffDH. The impact of DiffDH on early postoperative outcomes and achievement of textbook outcome (TO) was evaluated. Donor morphometry data on axial and coronal sections of donor CT at the level of portal bifurcation were collected. Donor and graft factors predictive of DiffDH were evaluated using univariate and multivariate logistic regression. ResultsOne hundred and eleven donors (Male-40.5%, Age-34± 9.5 years) underwent ORLDH during the study period. Difficulty score was constructed using five intra-operative parameters i.e. operating time, transection time, estimated blood loss, need for intra-operative vasopressors and need for Pringle maneuver. Donors were classified as DiffDH (score ≥ 2) or Standard DH (score<2). Twenty nine donors (26%) were classified as DiffDH. DiffDH donors suffered greater all cause morbidity (p=0.004) but not major morbidity (Clavien-Dindo score>2; p=0.651), more peri-operative transfusion (p=0.013), increased post-operative SIRS (p=0.034), delay in achieving full oral diet (p=0.047) and a 70% reduced chance of achieving TO as compared to StDH (p=0.007). On logistic regression analysis, increasing right lobe antero-posterior depth (RLdepth) was identified as an independent predictor of DiffDH (Odds ratio- 2.0(95% ci =1.2,3.3), p<0.006). ROC curve analysis identified RLdepth>14 cms as the best predictor of DiffDH (Sensitivity-79%, specificity-66%, Area under curve=0.803, p<0.001). ConclusionWe report a novel definition of DiffDH and show that it is associated with worse post-operative outcomes, including a lesser chance of achieving TO. We also report that DiffDH can be predicted from readily available donor CT parameters.

Marfan and Loeys-Dietz aortic phenotype: A potential tool for diagnosis and management

ObjectiveIn heritable aortic diseases, different vascular involvement may occur with potential variable implications in aortic dilation/dissection risk. This study aimed to analyze the aortic anatomy of individuals with Marfan syndrome and Loeys-Dietz syndrome to identify possible morphological differences. MethodsComputed tomography and magnetic resonance imaging of the thoracoabdominal aorta from the proximal supra-aortic vessels to the femoral bifurcation level of 114 patients with Marfan and Loeys-Dietz syndromes and 20 matched control subjects were examined. Aortic diameters, areas, length, and tortuosity were measured in different aortic segments using specific vessel analysis software. ResultsPatients with Marfan syndrome showed a higher prevalence of ascending aorta and aortic root dilation (P = .011), larger and longer aortic roots (P = .013) with pear-shaped phenotype, larger isthmus/descending aorta diameter ratio (P = .015), and larger suprarenal aorta and iliac arteries. Patients with Loeys-Dietz syndrome showed longer indexed segments and a significantly longer arch (P = .006) with type 2/3 arch prevalence (P = .097). Measurement ratios analysis provided cut-off values (aortic root to ascending aorta length/aortic root diameter, aortic root/sinotubular junction, aortic root/ascending aorta diameter) differentiating patients with Marfan syndrome from patients with Loeys-Dietz syndrome, even in the early stage of the disease. ConclusionsBoth syndromes show peculiar anatomic patterns at different aortic levels irrespective of aortic dilation and disease severity. These features may represent the expression of different genetic mutations on aortic development, with a potential impact on prognosis and possibly contributing to better management of the diseases. The systematic adoption of whole body imaging with magnetic resonance or computed tomography should always be considered, because they allow a complete vascular assessment with practical indicators of differential diagnosis.

MRI Extracellular Volume Fraction in Liver Fibrosis-A Comparison of Different Time Points and Blood Pool Measurements.

Extracellular volume (ECV) correlates with the degree of liver fibrosis. To analyze the performance of liver MRI-based ECV evaluations with different blood pool measurements at different time points. Prospective. 73 consecutive patients (n = 31 females, mean age 56 years) with histopathology-proven liver fibrosis. 3T acquisition within 90 days of biopsy, including shortened modified look-locker inversion recovery T1 mapping. Polygonal regions of interest were manually drawn in the liver, aorta, vena cava, and in the main, left and right portal vein on four slices before and after Gd-DOTA administration at 5/10/15 minutes. ECV was calculated 1) on one single slice on portal bifurcation level, and 2) averaged over all four slices. Parameters were compared between patients with fibrosis grades F0-2 and F3-F4 with the Mann-Whitney U and fishers exact test. ROC analysis was used to assess the performance of the parameters to predict F3-4 fibrosis. A P-value <0.05 was considered statistically significant. ECV was significantly higher in F3-4 fibrosis (35.4% [33.1%-37.6%], 36.1% [34.2%-37.5%], and 37.0% [34.8%-39.2%] at 5/10/15 minutes) than in patients with F0-2 fibrosis (33.3% [30.8%-34.8%], 33.7% [31.6%-34.7%] and 34.9% [32.2%-36.0%]; AUC = 0.72-0.75). Blood pool T1 relaxation times in the aorta and vena cava were longer on the upper vs. lower slices at 5 minutes, but not at 10/15 minutes. AUC values were similar when measured on a single slice (AUC = 0.69-0.72) or based on blood pool measurements in the cava or portal vein (AUC = 0.63-0.67 and AUC = 0.65-0.70). Liver ECV is significantly higher in F3-4 fibrosis compared to F0-2 fibrosis with blood pool measurements performed in the aorta, inferior vena cava, and portal vein at 5, 10, and 15 minutes. However, a smaller variability was observed for blood pool measurements between slices at 15 minutes. 1 TECHNICAL EFFICACY: Stage 3.

Pulmonary Venous Index as Additional Diagnostic Criteria for Fontan Palliation

Backgroud. The results of the Fontan operation, depending on the anatomy of the pulmonary arteries, have been studied quite well. Various indices have been proposed to assess the degree of hypoplasia of the pulmonary arterial bed (Nakata, Reddy, and McGoon indexes). At the same time, an obstruction of pulmonary venous blood return may be considered as a contraindication to Fontan operation. Aim of the Study. To present an optimal method for pulmonary venous index (PVI) calculation based on computed tomography angiography (CTA) enhancement of the heart data in patients with a functional single ventricle. Materials and Methods. 63 patients with a functional single ventricle (SV) underwent CTА (Philips, Brilliance iCT) before the Fontan operation. Axial sections were reconstructed to a thickness of 0.75–3 mm using soft tissue and lung filters, followed by postprocessing of the data (Horos and OsiriX software) and construction of multiplanar and 3D images. The diagnoses were presented by various types of SV of the heart. The age of the patients ranged from 3 to 30 years (median 7 years). Comparison of PVI was carried out in patients of two groups: those who survived the intervention (n = 55 patients) and those who died (n = 8). The evaluation of the pulmonary veins (PV) and the calculation of the pulmonary venous index (PVI) were carried out based on the measurement of each pulmonary vein at 2 levels (at the level of the orifices and bifurcation). The calculation of the PVI was carried out according to the formula: the sum of the cross-sectional area of the main pulmonary veins, related to the body surface area. 3 variants of PVI calculation were compared: taking into account the values of the PV areas at the level of the orifices, the bifurcation, and the sum of the minimum areas of each of the PVs. Results. In the group of survived patients, the median PVI at the level of the PV orifices was 292 mm/m2, and in the group of deceased, it was 242 mm/m2p=0.0326; at the level of PV bifurcation in the group of survivors, it was 299 mm/m2, and in the group of dead patients, it was 281 mm/m2p=0.0776; the minimum PVI was 257 mm/m2 in the survivor group and 218 mm/m2 in the deceased group p=0.006. An ROC analysis performed to determine the critical value of the minimum PVI affecting survival after Fontan operation revealed that PVI measured taking into account the minimum dimensions of the areas of the PV is a significant risk factor for death after Fontan operation p=0.00015, with its value (cutoff) &lt;233.5 mm2/m2. Conclusion. The value of the minimum PVI can be an important morphological indicator of the state of PV blood return and serve as an additional criterion in determining indications for the Fontan operation.

Root canal morphology of anterior permanent teeth in Jordanian population using two classification systems: a cone-beam computed tomography study

BackgroundAdequate knowledge of root canal morphology and its variation is essential for success of root canal treatment and to overcome treatemnt failure. The aim of this study was to investigate the root and canal morphology of mandibular anterior teeth using 2 classification systems.Methods3342 lower anteriors were evaluated from 557 CBCT scans. The images were examined in sagittal, axial and coronal views using a CS 3D imaging software (V3.10.4, Carestream Dental). Demographic data recorded, the number of roots and canal’s morphology were described according to Vertucci and Ahmed classifications.ResultsFrequency of Type I configuration was significantly the highest in incisors and canines (76%, N = 2539), followed by Type III (20.6%, N = 687). Type II (1.1%, N = 37), IV (1.1%, N = 37), and V (0.3%, N = 11) were rarely encountered. 0.9% (N = 31) of the teeth could not be classified with the Vertucci System. The frequency of 2 roots (2MA in Ahmed classification) which has no correspondence in the Vertucci classification, was 1.1% (N = 38), it was significantly higher in canines and in females (35 canines and 3 laterals). A moderate correlation in root canal morpology was found between the left and right sides (V > 0.30). 80% (N = 2538) of the teeth did not exhibit any divergence/merging. The bifurcation level occurred mostly in the middle third of the root.ConclusionsOne fourth of anterior teeth had variation from the simple type I canal configuration and therefore requires attention during treatment. The new classification system offers a more accurate and simplified presentation of canal morphology.Clinical relevanceThe prevalence and mid root bifurcation of second canal in lower anteriors requires attention to ensure adequate quality root canal treatment without compromising the integrity of teeth.

FLUID FLOW THROUGH ISOMERIC CONSTRUCTAL NETWORKS OF TUBES

The branching topology of tree networks has a considerable influence on the distribution of fluid flow inside them. Fluid flow asymmetry (an unequal distribution of fluid flow between the daughter tubes) can arise in geometrically symmetric branches. It is important to be able to pinpoint the reason for this, which is still not fully understood. This study compares tree flow network designs with the same number of tubes of equal sizes but attached to one another in various directions, i.e., network isomers. The flow resistance and fluid flow distribution assessment within the networks are calculated based on the computational fluid dynamics results. This study shows, among other results, that the flow asymmetries are more noticeable at higher bifurcation levels, and the performance of tree designs is highly dependent on how the tubes are arranged in the network, especially how they are aligned at different levels of bifurcation. Practical guidelines that can immediately produce significant insights into the relationship between the incidence of asymmetry in the flow and alignments of the tubes between levels are defined. The findings of this study will be useful to designers in improving the design and management of these networks.

FRACTAL ANALYSIS FOR PERMEABILITY OF MULTIPLE SHALE GAS TRANSPORT MECHANISMS IN ROUGHENED TREE-LIKE NETWORKS

In this work, a new gas transport model for shale reservoirs is constructed by embedding randomly distributed roughened tree-like bifurcation networks into the matrix porous medium. We constructed apparent permeability models for different shale gas flow mechanisms based on fractal theory, taking into account the effects of relative roughness and surface diffusion. The effects of bifurcation structure parameters as well as shale gas parameters on different apparent permeabilities are systematically analyzed. It is found that the permeability generally shows a decreasing trend with the increase in pore pressure, but the effect on viscous flow is inconsiderable. In addition, larger porosity, fractal dimension and bifurcation levels lead to increased permeability of different mechanisms. Whereas, the increase in the bifurcation levels implies a greater flow resistance, resulting in a decreased permeability. In addition, The relative roughness hinders the development of total permeability but favors surface diffusion permeability. Moreover, larger length ratios and diameter ratios are beneficial to the shale gas flow.

Integrative taxonomy of Anaporrhutum mundae sp. nov. (Trematoda: Gorgoderidae), a parasite of the Munda round ray Urotrygon munda (Urotrygonidae) in Costa Rica.

A new species of trematode of anaporrhutine gorgoderid, from the gill chambers of the Munda round ray Urotrygon munda in Costa Rica is described, based on an integrative taxonomic approach that includes the use of light and scanning electron microscopy, ITS2 and 28S rDNA sequencing, and phylogenetic analysis. Anaporrhutum mundae sp. nov. can be distinguished from congeneric species by a combination of morphological traits and particularly by having the genital pore opening at the level of the intestinal bifurcation. The new species also can be distinguished from all other species of Anaporrhutum, except A. euzeti Curran, Blend & Overstreet, 2003, by having fewer testicular follicles per testis. Anaporrhutum mundae sp. nov. also differs from A. euzeti in its forebody shape and by having different morphology and location of the vitellaria. The study of the tegumental surface of A. mundae sp. nov., as revealed by scanning electron microscopy, allowed detection of new morphological characters for a member of Anaporrhutinae that may be of taxonomic value. These are: a stylet cavity dorsal to the oral sucker with a large penetration gland opening on each side of the cavity and small penetration gland openings located ventral to the stylet cavity, arranged in a circle around the mouth. This represents the first record of an Anaporrhutum species from Costa Rica. Further, A. mundae sp. nov. represents the first parasite described or reported in this host.

Comparison of CT-Determined Pulmonary Artery Diameter among Smokers and Non-smokers: A Cross-sectional Study

Introduction: Tobacco smoking is a common addiction in our society. The toxic chemical compounds present in tobacco smoke cause epithelial damage and inflammation of the airways. Chronic smoking results in the thickening of the pulmonary arterial wall and vasoconstriction, leading to the development of pulmonary arterial hypertension. Hence, measurement of pulmonary artery diameter using Contrast Enhanced Computed Tomography (CECT) may be helpful in the early detection of pulmonary arterial hypertension. Aim: To compare the diameters of the Main Pulmonary Artery (MPA), Right Pulmonary Artery (RPA), and Left Pulmonary Artery (LPA) using CECT thorax in smokers and non-smokers. Materials and Methods: A cross-sectional study was conducted from April 2021 to March 2022 in the department of radiodiagnosis, KS Hegde Hospital, Karnataka, India, consisting of 100 patients referred for CECT thorax in the age group of 18-85 years. They were divided into two groups: smokers and non-smokers, with 50 patients in each group. They were further categorised into three age groups: &lt; 50 years, 50-60 years, and &gt;60 years. The widest diameters of the MPA were measured at the level of bifurcation of the artery and perpendicular to the long axis of the artery. At this level, RPA and LPA diameters were measured at the widest portion on 1.25 mm axial images of the arterial phase. Variation in the pulmonary artery diameter was compared between smokers and non-smokers with respect to age and analysed by unpaired t-test and Pearson correlation. Results: Diameters of MPA, RPA, and LPA were statistically significant (p&lt;0.05) in smokers compared to non-smokers. In smokers, MPA and RPA diameters correlated with age, which was statistically significant (p&lt;0.05). No significant correlation (p&gt;0.05) was shown between age and MPA, RPA, and LPA diameter in non-smokers. The mean MPA diameter showed a significant difference (p&lt;0.05) in all three age groups. Conclusion: The diameter of the pulmonary artery is statistically significant in smokers compared to non-smokers. Hence, assessment of pulmonary artery diameters among smokers using CECT thorax will help to diagnose Pulmonary Hypertension (PH) at an early stage.