Reshaping Covalent Nanowires by Exploiting an Unexpected Plasticity Mediated by Deformation Twinning.

Nanowires (NWs) are among the most studied nanostructures as they have numerous promising applications thanks to their various unique properties. Furthermore, the properties of NWs can be tailored during synthesis by introducing structural defects such as nano-twins, periodic polytypes, and kinks, i.e., abrupt changes in their axial direction. Here, this work reports for the first time the postsynthesis formation of such defects, achieved by exploiting a peculiar plasticity that may occur in nanosized covalent materials. Specifically, in this work the authors found that single-crystal CuO NWs can form double kinks when subjected to external mechanical loading. Both the microscopy and atomistic modeling suggest that deformation-induced twinning along the ( 1 ¯ 10 ) $( {\bar{1}10} )$ plane is the mechanism behind this effect. In a single case the authors are able to unkink a NW back to its initial straight profile, indicating the possibility of reversible plasticity in CuO NWs, which is supported by the atomistic simulations. The phenomenon reported here provides novel insights into the mechanisms of plastic deformation in covalent NWs and offers potential avenues for developing techniques to customize the shape of NWs postsynthesis and introduce new functionalities.

The female urethral closure mechanism during physical stress.

The closure of the urethra under the condition of stress is the result of a reflex contraction of the urethral rhabdosphincter and pelvic floor muscles. This is likely induced by activity of the abdominal muscles due to a sudden increase in abdominal pressure. This reflex contraction with an increase of urethral pressure occurs a few milliseconds before an increase in intraabdominal pressure. The urethral pressure increase during stress is only possible with fixation of the urethra by the pubourethral ligaments (PUL), facilitating urethral kinking. The highest and most important increase in pressure and resistance occurs in the distal urethra due to this kinking of the urethra.

Anatomical variations of the extracranial internal carotid artery: prevalence, risk factors, and imaging insights from CT-angiography.

PURPOSE: To determine the prevalence of different extracranial internal carotid artery (EICA) variations in CT angiography (CTA) of the neck and its predisposing factors. METHODS: In this retrospective study from 2021 to 2023 conducted in the radiology department of Shafa Hospital, Kerman, Iran, all patients who had undergone neck CTA were included. Expert radiologists blindly examined each CTA image for the following: EICA variations-coiling, kinking, straight morphology, and tortuosity-and the distance between the internal carotid artery and the apex of the epiglottis and the C2 lower margin. RESULTS: Of the 106 patients, the mean age was 55.9 ± 16.9 years. 64.2% were men, and 35.8% were women. Considering each patient's bilateral anatomy, the reported 70.28% (149/212) frequency of EICA variations of all arteries. Tortuosity, kinking, and coiling variation were found in 61.8%, 4.2%, and 4.2% of arteries, respectively. Also, 54.72%, 1.89%, and 0.94% of the participants had bilateral tortuosity, kinking, and coiling, respectively. There was a significant relationship between the prevalence of EICA variations and female sex, age, and hypertension. CONCLUSION: The frequency of EICA variations in arteries and patients was 70.28% and 73.58%, respectively. Tortuosity was the most common variation. Female sex, old age, and hypertension were significant risk factors for EICA variations.

An optimized framework for prediagnosis of diabetic retinopathy using HHO-CBL model.

BACKGROUND: Diabetic Retinopathy (DR) is a widespread intense stage of diabetes mellitus that causes vision-effecting anomalies in the retina. It is a medical health condition on the strength of fluctuating glucose level in the blood that can result in vision loss in case of severity. OBJECTIVE: As a result, early detection and treatment with DR is the most significant task which will tremendously reduce the likelihood of vision impairment and is still a difficult challenge. Many conventional methods fail to detect primary causes of formation of Microaneurysms, that are used to determine the Prediagnosis of DR. METHOD: To overcome this challenge, the proposed model incorporates Harris Hawk Optimization with CNN-Bi-LSTM (HHO-CBL) to extract the features. The Prediagnosis of DR has been achieved through this model by spotting saccular dilations, hyaline like material in the capillary aneurysm wall, kinking of vessels since these are the indications for the creation of microaneurysms that are spotted in the blood vessel of the retina. The recommended model is also used to automatically detect DR and its progression in many phases. Furthermore, in order to identify the severity of DR retina, we used a benchmark Kaggle APTOS dataset to train the HHO-CBL model. RESULTS: Experimental results reveal that this model obtains the best classification accuracy of 96.4 % for an early diagnosis and 98.8 % for a five-degree classification. In addition to those results, a comparison with previously carried out studies has also shown that this model provides a promising solution for a successful Prediagnosis of DR and its staging. CONCLUSIONS: In the current research, an innovative HHO-CBL was developed for identifying the primary causes that lead to the formation of microaneurysms and diagnosing all five grades of DR. According to the acquired results presented through the evaluation performance metrics indicates that the pre-early diagnosis and five grade classification using feature embedding technique outperformed the other prevailing approaches (Tab. 4, Fig. 10, Ref. 31).

Rescue version of a carotid micro-endarterectomy: an ACE-ICA anastomosis with proximal Ica and distal ACE hemoclip obliteration.

Aim of the study: To present our rescue approach of carotid artery occlusion as well as to discuss other possible techniques that can be applied in similar situations.Materials and methods: Two cases from our institution with acute complications during carotid micro-endarterectomy (CEA).Results: Two cases from our institution with acute postoperative complications during CEA that were successfully addressed are presented with imaging and detailed description of the surgical techniques used.Conclusion: CEA are common surgical procedures pursued to achieve revascularization of carotid arteries when occluded partially or fully by an atherosclerotic plaque. As with any surgical procedure, associated complications exist in small percentage of the cases. These can include blood flow limitation due to an insufficient artery wall after atherosclerotic plaque extraction as well as distal kinking of the internal carotid artery. A direct end-to-end ACE-ACI bypass with occlusion of the proximal ACI and distal ACE stump preserves distal flow to the ACI, however the original arteriotomy of ACC must be completely sutured up to the arterial stumps.

Association between internal carotid artery kinking and ischemic stroke: A population-based cross-sectional study.

AIM: Evidence for an association between Internal carotid artery (ICA) kinking and ischemic stroke has been controversial. We aimed to examine the association between ICA tortuosity and risk of ischemic stroke and specific ischemic stroke subtypes (large artery atherosclerosis, LAA; small artery occlusion, SAO). METHODS: A total of 419 outpatients were included in this cross-sectional study. ICA kinking was objectively assessed by head and neck computed tomography angiography (CTA). The risk of ischemic stroke for each patient was evaluated according to the Essen Stroke Risk Score (ESRS). Ischemic stroke subtypes (LAA and SAO) were measure with head magnetic resonance imaging (MRI). RESULTS: The average age of patients was 59.1 years (SD = 13.25) and 264 (63.0 %) were males. The prevalence of ICA kinking in this sample was 31.5 % (132 out of 419). Individuals with ICA kinking was associated with 0.55-points increase in ESRS score than those without ICA kinking (95 % CI, 0.28-0.81, p < 0.001) among patients over 50 years. In addition, right ICA kinking or left ICA kinking were associated with 0.35-points (95 % CI, 0.08-0.63) and 0.49-points (95 % CI, 0.23-0.76) increase in ESRS score, respectively. For specific ischemic stroke subtypes, individuals with ICA kinking had a 10.34-fold increased risk of SAO compared to those without ICA kinking (95 % CI, 6.22-20.68). Individuals with right ICA kinking had a 4.51-fold risk of SAO than those without kinking (95 % CI, 2.64-7.71), and had an 8.86-fold risk of SAO than those without kinking in the left ICA kinking (95 % CI, 4.97-15.79). CONCLUSION: Our findings support the role of ICA kinking on ischemic stroke. Early screening and proper treatment of carotid artery tortuosity could be a potential intervention strategy for the prevention of ischemic stroke later on.

Short- and long-term results of operative iliac artery release in endurance athletes.

OBJECTIVE: Endurance athletes can develop intermittent claudication due to sports-related flow limitations of the iliac artery (FLIA) caused by arterial kinking. In the present study, we investigated the short- and long-term efficacy of an operative release for iliac artery kinking. METHODS: Between 1996 and 2015, all patients with a diagnosis of FLIA due to iliac artery kinking without substantial arterial stenosis (<15%) or an excessive arterial length (vessel length to straight ratio, <1.25) who had undergone surgery were included. The short-term follow-up protocol consisted of cycling tests, the ankle brachial index with a flexed hip, and Doppler echography examinations to determine the peak systolic velocity before and 6 to 18 months after surgery. Additionally, the short- and long-term efficacy were evaluated using questionnaires. RESULTS: A total of 142 endurance athletes (155 legs; 88.4% male; median age, 26 years; interquartile range [IQR], 22-31 years) were available for analysis. In the short term, the symptoms had decreased in 83.9% of the patients, with an overall 80.3% satisfaction rate. Power during a maximal cycling test had improved from 420 W (IQR, 378-465 W) to 437 W (IQR, 392-485 W; P < .001). The symptom-free workload had increased from 300 W (IQR, 240-340 W) to 400 W (IQR, 330-448 W; P < .001). The postexercise ankle brachial index with a flexed hip had increased from 0.53 (IQR, 0.40-0.61) to 0.57 (IQR, 0.47-0.64; P = .002), and the peak systolic velocity with a flexed hip had decreased from 1.88 m/s (IQR, 1.45-2.50 m/s) to 1.52 m/s (IQR, 1.19-2.07 m/s; P < .001). Postoperative imaging studies revealed some degree kinking in 33.9%, mostly asymptomatic. The long-term results were evaluated after a median of 15.2 years (IQR, 10.9-19.5 years). The athletes had cycled an additional 125.500 km (IQR, 72.00-227.500 km), which was approximately equal to the 131.000 km (IQR, 98.250-220.000 km) cycled before the diagnosis of FLIA. On the long term, 63.9% of the athletes reported persistent reduction of complaints, with an overall 59.1% satisfaction rate. Eight patients had required reintervention, six because of treatment failure and two because of newly developed FLIA. CONCLUSIONS: Operative iliac artery release for sports-related functional kinking in the absence of stenosis or an excessive vessel length was effective for most athletes in the short and long term.

Early second-trimester three-dimensional transvaginal neurosonography of fetal midbrain and hindbrain: normative data and technical aspects.

OBJECTIVES: To provide a detailed description of the sonographic appearance and development of various fetal structures of the midbrain and hindbrain (MBHB) during the early second trimester, and to evaluate the impact of the frequency of the transvaginal sonography (TVS) transducer on the early recognition of these structures. METHODS: This was a retrospective analysis of three-dimensional volumetric datasets of the MBHB from apparently normal fetuses at 14-19 gestational weeks, acquired by TVS in the midsagittal view through the posterior fontanelle. Using a multiplanar approach, we measured the tectal thickness and length, aqueductal thickness, tegmental thickness and width and height of the Blake's pouch (BP) neck. In addition, we assessed the existence of early vermian fissures, the linear shape of the brainstem and the components of the fastigium. The correlation between gestational age according to last menstrual period and sonographic measurements of MBHB structures was evaluated using Pearson's correlation (r). A subanalysis was performed to assess the performance of a 5-9-MHz vs a 6-12-MHz TVS transducer in visualizing the MBHB structures in the early second trimester. RESULTS: Sixty brain volumes were included in the study, obtained at a mean gestational age of 16.2 weeks (range, 14.1-19.0 weeks), with a transverse cerebellar diameter range of 13.0-19.8 mm. We found a strong correlation between gestational age and all MBHB measurements, with the exception of the tectal, tegmental and aqueductal thicknesses, for which the correlation was moderate. There was good-to-excellent intraobserver and moderate-to-good interobserver correlation for most MBHB measurements. We observed that the BP neck was patent in all fetuses between 14 and 18 weeks with decreasing diameter, and that the aqueductal thickness was significantly smaller at ≥ 18 weeks compared with at < 16 weeks. The early vermian fissures and the linear shape of the brainstem were present in all fetuses from 14 weeks. We found that, in the early second trimester, the horizontal arm of the presumed 'fastigium' evolves from the fourth ventricular choroid plexus and not the posterior vermis, indicating that this is not the fastigium. Standard- and high-resolution TVS transducers performed similarly in the assessment of MBHB anatomy. CONCLUSION: Detailed early second-trimester assessment of the MBHB is feasible by transvaginal neurosonography and provides reference data which may help in the early detection of brain pathology involving the MBHB. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Contralateral Transradial Access for Coil Embolization of Distal Anterior Cerebral Artery Aneurysm Associated With a Steep Ipsilateral A1-A2 Angle.

OBJECTIVE: Endovascular treatment of distal anterior cerebral artery aneurysms is commonly addressed via the ipsilateral A1 segment of the anterior cerebral artery. However, when the parent pericallosal artery has a sharp ipsilateral A1-A2 angle, catheterization through the ipsilateral A1 segment can potentially result in vessel injury, catheter kinking, and/or compromised/stagnant anterior cerebral artery flow. Here, we present a case of a distal anterior cerebral artery aneurysm associated with a steep ipsilateral A1-A2 angle treated with contralateral transradial coil embolization. CASE PRESENTATION: A 91-year-old woman presented with a ruptured left distal anterior cerebral artery aneurysm at the A3 segment. The parent pericallosal artery had a steep ipsilateral A1-A2 angle. To safely achieve coil embolization of the aneurysm, a contralateral transradial system via the right A1 segment was employed. Although a secondary ipsilateral transradial system was required for contrast injection, aneurysm obliteration was successfully achieved without vessel injury or system instability. CONCLUSION: The A1-A2 angle can be a key anatomical factor in the endovascular treatment of distal anterior cerebral artery aneurysms. The contralateral transradial system is a useful treatment option for distal anterior cerebral artery aneurysms associated with sharp ipsilateral A1-A2 angles. However, if the distal anterior cerebral artery aneurysm cannot be clearly visualized through the contralateral system, an ipsilateral system will be required for contrast injection.

A Case Report: Is the Lack of Sufficient Radial Force Unfreezing the "Frozen Elephant Trunk"?

The "frozen elephant trunk" is a hybrid technique to treat aortic arch and proximal descending aortic pathologies in a single step. Despite its encouraging early and long-term results, some stent-graft-related adverse events have been reported. Here, we describe a possible treatment option to "re-freeze" the FET in case of loss of landing zone. We report a patient who developed significant kinking of the FET over the course of the first 2 postoperative years. The 1-year follow-up computed tomography angiography (CTA) showed significant kinking and proximal migration of the endograft portion of the FET, resulting in new thrombus formation. Due to kinking and thrombus progression in subsequent CTA follow-ups (2 years and 2½ years) with risk for peripheral embolization, a secondary endovascular repair was indicated. Transfemoral relining of the stent component with a thoracic aortic endovascular repair (Zenith®TX2®30142) stent-graft was performed. In the context of postoperative aneurysm sac shrinkage, the low radial force and lack of longitudinal stiffness of the hybrid graft may lead to proximal migration, thus secondary kinking, emphasizing the importance of an adequate degree of oversizing of the primary graft and an appropriate follow-up. Selection of a suitable graft for a particular pathology concerning the radial force and longitudinal stiffness is furthermore important.

Is location of urethral kinking a confounder of association between urethral closure pressure and stress urinary incontinence?

OBJECTIVES: Intact urethral support and normal sphincter function are deemed important for urinary continence. We aimed to test whether the location of urethral kinking (as the probable anatomical correlate of maximal pressure transmission) is associated with stress urinary incontinence and/or urodynamic stress incontinence. METHODS: This was a retrospective study of women seen at a tertiary urogynecological center in 2017. Patients had undergone an interview, multichannel urodynamic testing and four-dimensional translabial ultrasound examination. Those with a history of anti-incontinence surgery, absence of urethral kinking on ultrasound and/or missing or inadequate ultrasound volume data were excluded. Volume data were used to assess urethral mobility using a semi-automated Excel® urethral motion profile program. Mobility vectors were calculated using the formula √((x valsalva - x rest )2 + (y valsalva - y rest )2 ), where x and y are the coordinates of six equidistant points along the length of the urethra from the bladder neck to the external urethral meatus. The location of urethral kinking was identified as a concave contour of the urethra on the vaginal side in the midsagittal plane on maximum Valsalva maneuver. The distance between the center of the kink and the bladder neck was measured and expressed as a centile in relation to the total length of the urethra, using the formula: (distance from bladder neck/total length of urethra) × 100. Univariate and multivariate analyses were performed to test the associations of stress urinary incontinence and urodynamic stress incontinence with age, maximum urethral pressure, urethral mobility vectors and location of urethral kinking. RESULTS: Of 450 women seen during the study period, 61 were excluded owing to previous incontinence surgery and 82 owing to absence of urethral kinking, inadequate volume data or missing data, leaving 307 women included, of whom 227 (74%) complained of stress urinary incontinence and 211 (69%) complained of urgency urinary incontinence. 190 (62%) of the women were diagnosed with urodynamic stress incontinence. On multivariate analysis, maximum urethral pressure (36 vs 50 cmH2 O; P < 0.001), mid-urethral mobility (2.27 vs 2.03 cm; P = 0.003) and location of urethral kinking (63.1st vs 59.7th centile; P = 0.002) were associated significantly with urodynamic stress incontinence. The location of urethral kinking was associated with stress urinary incontinence on univariate analysis (P = 0.026) but not on multivariate analysis (P = 0.21). CONCLUSIONS: The location of urethral kinking is associated with urodynamic stress incontinence. The further urethral kinking is from the mid urethra, the more likely is urodynamic stress incontinence. This provides circumstantial evidence for the pressure-transmission theory of stress urinary continence. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Positional outflow obstruction as a cause of early refractory ascites post-pediatric living donor liver transplantation.

Refractory ascites post-liver transplantation can be a challenging problem. Causes of refractory ascites include venous outflow anastomotic stenosis, vessel kinking by the regenerating liver, pre-existing graft disease, and positional outflow obstruction. We present a case report of a child presenting with high drain output and refractory ascites post-LDLT secondary to a positional kinking. Repeating the Doppler studies with patients both supine and sitting may be helpful.

Symptomatic internal carotid artery dissection and kinking in a patient with fibromuscular dysplasia.

Isolated dissection of the internal carotid artery (ICA) is rare in young patients and is a cause for strong suspicion of fibromuscular dysplasia (FMD), especially when associated with artery elongation and tortuosity. The natural history of cerebrovascular FMD is unknown and management of symptomatic patients can be challenging. We report the case of a 44-year-old female patient with a history of transient ischemic attack in the absence of cardiovascular risk factors, associated with an isolated left ICA dissection and kinking. Carotid duplex ultrasound confirmed the diagnosis of dissection and demonstrated severe stenosis of the left ICA. The patient underwent surgical repair and histopathological evaluation confirmed the diagnosis of FMD with dissection. An autogenous great saphenous vein bypass was performed and the patient had an uneventful recovery. Cervical carotid artery dissection can be related to underlying arterial pathologies such as FMD, and the presence of ICA tortuosity highlights certain peculiarities for optimal management, which might be surgical.

A dissecção isolada da artéria carótida interna em pacientes jovens é rara, e a displasia fibromuscular deve ser altamente suspeitada principalmente quando estiver associada a alongamento e tortuosidade da artéria. A história natural da displasia fibromuscular cerebrovascular é desconhecida, e o manejo de pacientes sintomáticos pode ser desafiador. Apresentamos o caso de uma paciente de 44 anos com histórico de ataque isquêmico transitório sem fatores de risco cardiovasculares, associado a dissecção e acotovelamento isolados da artéria carótida interna esquerda. O ultrassom duplo das carótidas confirmou o diagnóstico de dissecção e demonstrou estenose grave na artéria carótida interna esquerda. A paciente foi submetida a reparo cirúrgico, e a avaliação histopatológica confirmou o diagnóstico de displasia fibromuscular com dissecção. Foi realizada cirurgia de ressecção do segmento e reconstrução com veia safena magna autógena, e a paciente se recuperou sem complicações. A dissecção da artéria carótida cervical pode estar relacionada a doenças arteriais subjacentes, como a displasia fibromuscular, e a presença da tortuosidade da artéria carótida interna destaca algumas particularidades no manejo ideal, o qual pode ser cirúrgico.

Clinical variability in children with dolichoarteriopathies of the internal carotid artery.

INTRODUCTION: Dolichoarteriopathies of the internal carotid artery (DICA) are frequent non-atheromatous anatomical changes in the general population. The etiology of DICA is still controversial: several hypotheses have been suggested, including an anomaly of embryological development, or a degenerative loss of elasticity of the vessel wall. DICA have been related to a wide spectrum of clinical presentations in adults, varying from asymptomatic forms to acute cerebrovascular events. However, to date, only a few pediatric cases have been reported. METHODS AND RESULTS: We report seven patients with DICA, 6 males and 1 female, aged 3 to 13 years, presenting with variable clinical symptoms. Different imaging techniques, including color Doppler ultrasound and magnetic resonance angiography, were used to show loops and/or kinking of the ICA. Three of these patients received a diagnosis of Ehlers-Danlos syndrome (EDS). DISCUSSION: This study highlights the clinical variability in pediatric patients with DICA. We emphasize the need for close clinical management of pediatric DICA. Finally, considering the long-term prognostic implications of EDS, we recommend specific testing in children with DICA and suspicious clinical signs of this pathology.

Stability Analysis of Arteries Under Torsion.

Vascular tortuosity may impede blood flow, occlude the lumen, and ultimately lead to ischemia or even infarction. Mechanical loads like blood pressure, axial force, and also torsion are key factors participating in this complex mechanobiological process. The available studies on arterial torsion instability followed computational or experimental approaches, yet single available theoretical study had modeled the artery as isotropic linear elastic. This paper aim is to validate a theoretical model of arterial torsion instability against experimental data. The artery is modeled as a single-layered, nonlinear, hyperelastic, anisotropic solid, with parameters calibrated from experiment. Linear bifurcation analysis is then performed to predict experimentally measured stability margins. Uncertainties in geometrical parameters and in measured mechanical response were considered. Also, the type of rate (incremental) boundary conditions (RBCs) impact on the results was examined (e.g., dead load, fluid pressure). The predicted critical torque and twist angle followed the experimentally measured trends. The closest prediction errors in the critical torque and twist rate were 22% and 67%, respectively. Using the different RBCs incurred differences of up to 50% difference within the model predictions. The present results suggest that the model may require further improvements. However, it offers an approach that can be used to predict allowable twist levels in surgical procedures (like anastomosis and grafting) and in the design of stents for arteries subjected to high torsion levels (like the femoropopliteal arteries). It may also be instructive in understanding biomechanical processes like arterial tortuosity, kinking, and coiling.

Surgical treatment of outflow graft kinking complicated by external obstruction with a fibrin mass in a patient with LVAD.

BACKGROUND: Outflow graft (OG) obstruction is a dangerous complication that may occur for various reasons after left ventricular assist device (LVAD) implantation. CASE SUMMARY: We describe the case of a 51-year-old patient on LVAD support who developed significant OG kinking and external OG obstruction due to a fibrin mass causing severe stenosis. Both the OG kinking and external obstruction were eliminated via a left lateral thoracotomy.

[Surgical treatment of internal carotid artery kinking following fibromuscular dysplasia]. / Rezul'taty khirurgicheskogo lecheniya patologicheskoi izvitosti vnutrennei sonnoi arterii na fone fibrozno-myshechnoi displazii.

OBJECTIVE: To evaluate the results of surgical treatment of internal carotid artery kinking following fibromuscular dysplasia. MATERIAL AND METHODS: There were 32 patients who underwent surgical treatment of internal carotid artery kinking following fibromuscular dysplasia. Structural changes of carotid artery wall were analyzed using immunohistochemical survey. Considering destructive changes revealed, we divided all patients into 2 groups in order to assess long-term postoperative outcomes: 1 - ICA resection followed by anastomosis in end-to-end fashion; 2 - ICA replacement. Postoperative analysis included incidence of stroke, thrombosis and deformities of anastomosis zone, regression of cerebrovascular insufficiency. RESULTS: The main «phenotype¼ of arterial wall in patients with ICA kinking following fibromuscular dysplasia is a large number of smooth muscle cells releasing matrix matelloproteinases-2 and -9 and low level of their tissue inhibitor type 1. Postoperative deformities are more common within a year after surgery. Maximum incidence is observed after 12 months. Both ICA resection and replacement are followed by similar incidence of deformity later. No severe deformities were diagnosed. Resection of ICA kinking on the background of fibromuscular dysplasia is followed by comparable results with ICA replacement regarding the incidence stroke, thrombosis and regression of cerebrovascular insufficiency. CONCLUSION: Despite degradation of extracellular matrix, destruction of elastic fibers and their fragmentation, no significant deformities are observed in long-term postoperative period in patients with ICA kinking and fibromuscular dysplasia.

Long-term outcomes of endoscopic treatment for duct-to-duct anastomotic strictures after living donor liver transplantation.

BACKGROUND AND AIMS: The anastomotic biliary stricture is a clinically important complication after living donor liver transplantation (LDLT) with a duct-to-duct anastomosis. Although endoscopic management of post-LDLT biliary strictures using balloon dilation (BD) and plastic stents (PSs) has provided acceptable short-term outcomes, long-term outcomes and prognostic factors for treatment success remain unclear. METHODS: We included 96 patients with post-LDLT biliary strictures who were endoscopically managed between 2003 and 2016. BD was utilized as a first-line treatment strategy, and PS placement was carried out for refractory cases. Potential prognostic factors for biliary stricture resolution were analysed using logistic regression analyses. RESULTS: Endoscopic treatment was technically successful in 84 patients (87.5%). The overall rate of biliary stricture resolution was 44.8% (43 of 96 patients) with a median follow-up duration of 90.9 months (interquartile range, 30.9-122.3 months). Bile duct kinking was associated with a lower rate of biliary stricture resolution (odds ratio, 0.33; 95% confidence interval, 0.13-0.87). After successful endoscopic treatment, biliary strictures recurred in 22 patients (57.9%) after BD, and in one patient (4%) after PS treatment. CONCLUSIONS: Despite a high technical success rate, endoscopic treatment only provided a low rate of resolution of anastomotic biliary strictures among LDLT patients and required prolonged treatment duration. Alternative strategies including the use of a covered metal stent should be evaluated to further improve the treatment outcomes of post-LDLT biliary strictures, particularly in those accompanied by the bile duct kinking.

Common carotid artery kinking is a predictor of cardiovascular events: A long-term follow-up study using carotid ultrasonography.

BACKGROUND: Kinking of the internal carotid artery is a cardiovascular (CV) risk factor. However, it remains unclear as to whether kinking of the common carotid artery (CCA) can also predict CV events. We conducted a long-term follow-up study to examine whether CCA kinking as assessed by carotid ultrasonography is a predictor of CV events in asymptomatic patients with CV risk factors. METHODS: We enrolled 598 patients (mean age, 66.8 ± 11.8 years) who were divided into two groups according to CCA kinking severity: kinking of 0-29° (Group I); and kinking at ≥30° (Group II). We assessed whether CCA kinking predicts CV events during follow-up. RESULTS: A total of 91 CV events were observed during the follow-up period (median, 124 months). Hypertension (P < .0001), prior CV events (P < .0001), CCA kinking (P < .0001), intima-media thickness (P < .0001), and max plaque score (P < .0001) were significantly higher in patients with CV events than those without. The age-adjusted hazard ratio of CCA kinking for CV events was 3.42 (95% CI: 2.2-5.3) in Group II compared to Group I. Cox proportional hazard regression analysis revealed that CCA kinking (HR: 3.02, 95% CI: 1.97-4.67), prior CV events (HR: 2.53 95% CI: 1.604.00), hypertension (HR: 2.19 95% CI: 1.17-4.57), and age (HR: 1.04, 95% CI: 1.02-1.07) were independent predictors of CV events. CONCLUSION: CCA kinking is a powerful independent predictor of CV events in asymptomatic patients with CV risk factors.

Intracranial stenting after tumor exeresis complicated by delayed kinking of the middle cerebral artery.

During intracranial tumor resection, the delayed kinking of a major encased vessel has never been described in literature. We present a case which required urgent endovascular treatment performed through a stent positioning. A patient was hospitalized with symptomatic sphenoid meningioma in the left middle cranial fossa. Twelve days after surgery, right-sided hemiplegia and aphasia occurred. Digital subtraction arteriography revealed a kinking of the M1 segment of the left middle cerebral artery and diffuse vasospasm. At first, intra-arterial nimodipine has been administered, obtaining the remission of the vasospasm. Secondly, a stent was positioned to treat the kinking, achieving a complete flow restoration.