Stenotic Segment Research Articles

Finite element analysis of braided dense-mesh stents for carotid artery stenosis

When braided dense-mesh stents are used to treat carotid stenosis, the structural mechanics of vascular stents, the contact mechanics with blood vessels, and the fluid mechanics in the blood environment need to be studied in depth to reduce the damage of stents to blood vessels and the incidence of in-stent restenosis. Three types of braided stents with 8, 16, and 24 strands and laser-cut stents with the corresponding size parameters were designed, and the bending behavior of each of these types of stent, deployment, and fluid dynamic analysis of the 24-strand braided stent were simulated. The results show that the bending stress of the 8-, 16-, and 24-strand braided stents is 46.33%, 50.24%, and 31.86% of that of their laser-cut counterparts. In addition, higher strand density of the braided stents was associated with greater bending stress; after the 24-strand braided stent was expanded within the stented carotid artery, the carotid stenosis rate was reduced from 81.52% to 46.33%. After stent implantation, the maximum stress on the vessel wall in a zero-pressure diastolic environment decreased from 0.34 to 0.20 MPa, the maximum pressure on the intravascular wall surface decreased from 4.89 to 3.98 kPa, the area of high-pressure region decreased, the wall shear force of the stenotic segment throat decreased, and blood flow increased in the stenosis segments. The braided stent had less bending stress and better flexibility than the laser-cut stent under the same stent size parameters; after the 24-strand braided stent was implanted into the stented vessel, it could effectively dilate the vessel, and the blood flow status was improved.

Mucosa-Associated Oscillospira sp. Is Related to Intestinal Stricture and Post-Operative Disease Course in Crohn's Disease.

Intestinal stricture remains one of the most intractable complications in Crohn's disease (CD), and the involved mechanisms are poorly understood. Accumulating evidence suggests that the gut microbiota contributes to the pathogenesis of intestinal fibrosis. In this study, we investigated specific mucosa-associated microbiota related to intestinal strictures and their role in predicting postoperative disease course. Twenty CD patients who had undergone operative treatments were enrolled and followed up. Intestinal mucosa and full-thickness sections from stenotic and non-stenotic sites were sterilely collected. DNA extraction and bacterial 16s rRNA gene sequencing were conducted. Radiological and histological evaluations were performed to assess fibrosis. Microbial alpha diversity was significantly decreased in stenotic sites (p = 0.009). At the genus level, Lactobacillus, Oscillospira, Subdoligranulum, Hydrogenophaga, Clostridium and Allobaculum were decreased in stenotic segments (p < 0.1). The difference in Oscillospira sp. (stenotic vs. non-stenotic) was negatively correlated with the erythrocyte sedimentation rate (correlation coefficient (CC) -0.432, p = 0.057) and white blood cell count (CC -0.392, p = 0.087) and positively correlated with serum free fatty acids (CC 0.575, p < 0.05). This difference was negatively associated with intestinal fibrosis evaluated by imagological and histological methods (CC -0.511 and -0.653, p < 0.05). Furthermore, CD patients with a higher abundance of Oscillospira sp. in the residual intestine might experience longer remission periods (p < 0.05). The mucosa-associated microbiota varied between stenotic and non-stenotic sites in CD. Most notably, Oscillospira sp. was negatively correlated with intestinal fibrosis and postoperative disease course. It could be a promising biomarker to predict post-operative disease recurrence and a microbial-based therapeutic target.

Symptomatic Chronic Severe Stenosis of the Iliac Vein Successfully Treated Endovascularly Using an Interventional Radiology Computed Tomography System

We report a woman with chronic severe stenosis of the left common and external iliac veins and severe post-thrombotic syndrome symptoms. We successfully recanalized the stenotic segment via interventional radiology, which immediately relieved the symptoms. The interventional radiology computed tomography system was helpful for the safe and precise performance of endovascular treatments.

Numerical computations of blood flow through stenosed arteries via CFD tool OpenFOAM

This research culminates the arterial blood flow analysis through distinct stenotic regions. Four different forms of stenotic regions are woven together in present study, i.e. triangular, trapezoidal, overlapping (w-shape) and composite formations. The four reviewed stenotic formations are first time considered in such numerical analysis. The considered problem is modeled for an elliptical cross-sectional artery by means of cartesian coordinate system. The governing coupled Partial differential equations are decoded numerically over this elliptical cross-section by using free source CFD software Open-FOAM. A precisely refined and proper mesh is generated for each arterial stenotic segment. A high magnitude of flow profile with some minor disruptions is observed near the origin of stenotic sections of artery. Pressure profile also has high values near the sharp corners of stenotic regions. Some expected irregularities in the flow profile are observed near the origin of stenotic regions as it happens in most of the real-life stenosed artery blood flow problems.

A Prospective Institutional Study on Aetiopathogenesis, Management and Complications of Laryngotracheal Stenosis.

The main purpose of this study is to evaluate and understand the clinical profile of patients presenting to an Indian tertiary care referral centre with Laryngotracheal Stenosis (LTS) and also to emphasise on the outcomes after treatment in these patients.This is a prospective observational study conducted at a tertiary care referral centre which included 18 patients diagnosed with LTS. All patients were evaluated clinically and radiologically to evaluate the degree of stenosis, site and length of the stenotic segment involved, intervened surgical procedure, intraoperative and postoperative complications following the procedure were all documented and taken into consideration.The data collected was analysed. The most common etiological cause of LTS was post intubation (77.8%). 61.5% among the 13 intubated patients had a history of intubation for more than 10 days. 83.3% of the cases had stenosis at the level of the subglottis and cervical trachea level.Post intubational airway stenosis is the most common cause of LTS. A precise assessment of the laryngotracheal complex is the cornerstone of LTS management. The choice of treatment depends on the location, severity, and length of stenosis, as well as on the patient's comorbidities, history of previous interventions, and on the expertise of the surgical team. Application of topical Mitomycin c during surgery reduces the incidence of granulations. Close postoperative follow up for a long time and the necessity of more than one intervention improves results and can spare patients the morbidity and mortality associated with acute airway obstruction.

Role of diffusion kurtosis imaging in evaluating microstructural changes in spinal cord of patients with cervical spondylosis.

Analytical cross-sectional study. To study the role of diffusion kurtosis imaging (DKI) in evaluating microstructural changes in patients with cervical spondylosis. Cervical spondylosis is a common progressive degenerative disorder of the spine. Conventional magnetic resonance imaging (MRI) can only detect the changes in the spinal cord once there are visual signal changes; hence, it underestimates the extent of the injury. Newer imaging techniques like Diffusion Tensor and Kurtosis Imaging can evaluate the microstructural changes in cervical spinal cord before the obvious signal changes appear. Conventional MRI, diffusion tensor imaging (DTI), and DKI scans were performed for 90 cervical spondylosis patients on 1.5-T MR Siemens Magnetom aera after obtaining informed consent. Eight patients were excluded due to poor image quality. Fractional anisotropy (FA) colour maps and diffusion kurtosis (DK) maps corresponding to spinal cord cross sections at C2-C3 intervertebral disc level (control) and at the most stenotic levels were obtained. Modified Japanese Orthopaedic Association (mJOA) scoring was used for clinical assessment of the spinal cord function. The changes in DTI and DKI parameters and their correlation with mJOA scores were analysed by SPSS 23 software. In our study, mean FA and mean kurtosis (MK) values at the stenotic level (0.54, 1.02) were significantly lower than values at the non-stenotic segment (0.70, 1.27). The mean diffusivity (MD) value at the stenotic segment (1.25) was significantly higher than in the non-stenotic segment (1.09). We also observed a strong positive correlation between mJOA score and FA and MK values and a negative correlation between mJOA score and MD values, suggesting a correlation of FA, MK, and MD with the clinical severity of the disease. Addition of DTI and DKI sequences helps in early identification of the disease without any additional cost incurred by the patient.

Long-term outcomes of carotid artery stenting in patients with carotid artery stenosis: A single-center 14-year retrospective analysis.

Carotid artery stenting (CAS) is currently widely used for the treatment of carotid artery stenosis. The objective of this study was to analyze the outcomes of CAS performed in a single institution. We retrospectively analyzed 313 CAS cases from January 2007 to December 2020, including 206 (66%) symptomatic and 107 (34%) asymptomatic cases. Procedure-related morbidity and mortality were assessed. Rates of periprocedural (≤30 days after CAS) and postprocedural ipsilateral strokes (>30 days after CAS) were also assessed. Logistic regression analysis was used to identify risk factors for the periprocedural complication, in-stent restenosis (ISR), and ipsilateral stroke. The success rate of CAS was 98%. Among 313 cases, 1 patient died due to hyperperfusion-related intracerebral hemorrhage (ICH). The CAS-related mortality rate was 0.31%. The overall incidence of periprocedural complications is 5.1%. A risk factor for periprocedural complication was a symptomatic carotid artery stenosis (7.3% vs. 0.9%, p=0.016). Twenty cases of ISR occurred during 63.7±42.1 months of follow-up. The overall incidence of ISR was 10.2% (20/196). A risk factors for ISR were diabetes mellitus (17.6% vs. 5.7%, p=0.008) and patients who used Open-cell stents (19.6% vs. 6.9%, p=0.010). The overall incidence of ipsilateral stroke is 5.6%. A risk factors for ipsilateral stroke was ISR (95% CI, p=0.002). CAS is a safe and effective procedure for carotid artery stenosis. Although the incidence of complications is low, fatal complication such as hyperperfusion- related ICH can occur. To prevent hyperperfusion-related ICH, several methods such as strict blood pressure (BP) control, intentional less widening of stenotic segment should be used. To prevent ISR or stroke occurrence, special attention should be paid to patients who have ISR or ipsilateral stroke risk factors.

P195 Is fecal calprotectin truly valuable in the management of isolated small bowel Crohn’s disease?

Abstract Background Crohn’s disease (CD) is a complex inflammatory bowel disease (IBD) with different locations and behaviors. Although fecal calprotectin (FC) is recommended [1, 2] and has been used to monitor IBD, clinical practice has raised doubts about its utility in small bowel (SB) CD. Even though initial studies did not find a role for FC in SB CD, recent literature confirmed its acuity in SB active inflammation [2]. In fact, recent studies have confirmed a correlation between FC values and the degree in inflammatory activity in magnetic resonance enterography (MRE) [3, 4, 5, 6]. However, all these studies included patients with simultaneous colonic disease. Therefore, we evaluated the role of FC in predicting active inflammation in patients with isolated SB CD. Methods 40 patients with L1 CD according to Montreal classification [7] who underwent MRE, FC and C-reactive protein (CRP) assessment [maximum time between all exams was 60 days] were included. MRE data included disease location and extension, SB wall thickness and contrast enhancement, presence of SB dilation, fistulous tracts, inflammatory masses or abscesses, mesenteric findings. FC was both evaluated as a continuous variable and divided into 3 categorical variables: &amp;lt; 50 mg/g (“negative”), 50-150 mg/g (“low”) and &amp;gt; 150 mg/g (“high”). CRP was also divided in &amp;lt; 0.5 mg/dl (“negative”), 0.5-1 mg/dl (“low”) and &amp;gt; 1 mg/dl (“high”). Non parametric tests were used to correlate MRE findings with continuous FC and CRP values and Pearson’s chi-squared test was used to correlate categorical FC and CRP values. Results FC values ranged from 0 to 2872 mg/g, with an average of 301 mg/g. 31.7% had “negative”, 24.4% “low” and 43.9% “high” FC values. Table 1 represents MRE findings. We found a significant statistical correlation between both continuous and categorical FC values with positive mesenteric findings (p=0.0283 and p=0.037), increased bowel wall thickness (p=0.0455 and p=0.039) and presence of stenotic segments (p=0.0193 and p=0.05). All stenosis had signs of active inflammation. We did not find any correlation between FC and disease location or extension, bowel wall contrast enhancement or presence of penetrating disease. CRP values did not correlate with any of MRE findings. Conclusion Although imaging exams are essential for initial evaluation and treatment response in ileal disease, FC is a useful tool to evaluate active disease in isolated SB CD with both inflammatory (B1) and stenotic (B2) disease, in predominantly inflammatory stenosis. Our results do not support FC use to monitor penetrating (B3) disease.

Mini-probe endoscopic ultrasound for the diagnosis of congenital esophageal or duodenal stenosis.

The usefulness of endoscopic ultrasound (EUS) in pediatric populations has been recently appreciated; however, published studies on mini-probe EUS in the diagnosis of congenital esophageal stenosis (CES) or congenital duodenal stenosis (CDS) in pre-school patients remain scarce. This study aimed to report the utility of mini-probe EUS for the diagnosis of CES or CDS in pre-school patients based on the etiology. We retrospectively reviewed the medical records of pediatric patients with CES or CDS who underwent mini-probe EUS through the stenotic segments at our hospital between December 2006 and December 2021. Five patients with CES and one with CDS were enrolled. The median age and body weight when EUS was performed were 12.5months and 8.5kg, respectively. Hypoechoic lesions were observed on EUS in three patients, which were assessed as cartilage; one patient had no hypoechoic lesion but had a focal thickness of the muscular layer. They were diagnosed with tracheobronchial remnants based on EUS. The full circumferential wall thickness of the esophagus was visualized in one patient with fibromuscular hypertrophy. The histopathological findings confirmed the diagnoses. In the patient with CDS, EUS findings revealed pancreatic parenchyma encircling the stenotic part of the duodenum. The preoperative diagnosis was annular pancreas. The patient underwent duodenoduodenostomy, and intraoperative findings confirmed the diagnosis. Mini-probe EUS can be recommended as a feasible and safe technique for infants and toddlers. It can effectively diagnose CES or CDS based on etiology and can inform treatment strategies for pre-school patients.

Laryngotracheal Stenosis: Our Experience in a Tertiary Care Hospital.

Laryngotracheal stenosis is a recalcitrant disease with high morbidity. Laryngotracheal stenosis can be defined as a partial or circumferential narrowing of the airway and may be congenital or acquired. Sites involved are supraglottis, glottis, or sub glottis. The goal of treating the patient with laryngotracheal stenosis is to reconstruct an adequate airway while preserving phonation and airway protection. Furthermore, there is no fixed treatment for laryngotracheal stenosis, the choice of surgical procedure is determined by the individual anatomy, involved site, length and luminal narrowing of stenotic segment and function of the larynx and trachea, together with patient factors and available facilities. To determine the most common aetiology of laryngotracheal stenosis and to study outcome of various treatment modalities and their efficacies according to the site of stenosis and time of presentation. We have prospectively studied 25 cases of laryngotracheal stenosis who presented in Department of ENT, Civil Hospital, Ahmedabad from May 2019 to December 2021. All patients with clinical suspicion of laryngotracheal stenosis underwent CECT Neck and Thorax with virtual bronchoscopy, flexible bronchoscopy and graded according to myer cotton classification and then included in study. In our study of 25 patients 19 patients had history of intubation. Out of 25 patients, 5 Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation patients had supraglottic stenosis, 14 had subglottic stenosis and 6 patients had tracheal stenosis. 20 patients were tracheostomised. Bilateral vocal cord mobility is pre requisite for any surgical intervention and for decannulation of tracheostomy tube. Laser ablation is best modality for supra glottis stenosis patients. Treatment options of subglottic and tracheal stenosis patients depends on vocal cord mobility, % of luminal narrowing and type of stenosis on flexible bronchoscopy and CT scan. Patients of subglottic or tracheal stenosis having Myer cotton grading 1 or 2 were successfully treated by Laser + Balloon dilatation while grade 3 or 4 by resection and end to end anastomosis. Endoscopic CO2 laser ablation with/without balloon dilatation gives promising results in cases of supra glottic stenosis and in soft, mucosal, short segment (< 1.5cm), grade 1 or 2 stenosis patients with subglottic or tracheal stenosis. In patients with subglottic or tracheal stenosis having hard, cartilage framework involvement, > 1.5cm stenotic segment, Grade 3 or 4 needed external open approach like tracheal resection and end to end anastomosis.

Examination of whole lengths of coronary arteries by color flow echocardiography

Introduction: increased cases of cardiac diseases in our world, and the absence of non-invasive, accurate, and feasible method of examination necessitate the looking for one's which achieved these criteria, that is the visualization of the coronary arteries (CAs) by means of the color flow transthoracic echocardiography. Aim of work: To check the possibilities of color flow mode of Transthoracic Echocardiography for seeing the whole lengths of coronary arteries and areas of stenosis, dilatations, and possibilities of visualization of collateral vessels. Materials and Methods: In Adhale governorate, Yemen republic, an observational study was conducted at Dr. Nashwan Al-Ashwal Clinic for medical and cardiac diseases. Cases were selected randomly. The total number of them was 763 participants, 700 males and 63 female ranging from 5 months to 70 years old, and then divided into two groups; 228 control and 535 patients. Period of study was from 1st January to 31th December 2021. The collected information was entered into Microsoft excel and word. Technique of examination by using of routine transthoracic echocardiography and the color flow mode with adjustments of its parameters as explained in the context. Results: A success in visualization of the whole lengths of coronary arteries in all patients (100%), in addition to some other features also were seeing, as the following: "group 1" few areas of beaded shape scattered along the vessel course, and one or two blue segments connecting the red vessel end to end of the same artery, and small area/areas of either red or blue colors with network shapes, while in "group 2"; there are more beaded areas, more than two areas of mosaic color reflections (stenosis), arterial segment/segments with dilatation, more than two blue segments of short or long distances that connecting end to end of the same red (artery) vessel and to another vessel/vessels, local and diffused color changes in the blue (collateral arteries or connector vessel) or red vessels to tint white or yellow colors respectively, large areas of either red or blue color (network arteries), blood pooling focus that pumping blood into more than one areas distal to level/levels of coronary arteries stenosis, and lastly, appearance of a darken area/side in the left ventricle. decreased in /absence of blood vessels, particularly, the red ones, in few patients with severe ischemic dilated cardiomyopathy. Conclusion: The examinations by color flow mode of transthoracic echocardiography permits the visualization of whole lengths of coronary arteries, stenotic and dilated segments, in addition to the small coronary arteries and the collateral vessels or rescuing circulation, and discovered that the collateral circulation is in needs for higher pressure in the pre stenotic segments, to open their vessels one by one, and also to facilitate blood flowing through the stenotic segments before development of collateral circulations, that also affected by atherosclerotic changes, and leads to arise of blood pooling focus.

Analysis of the efficacy and risk factors of surgical treatment of recurrent UPJO in adults

BackgroundTo compare the efficacy of secondary pyeloplasty and balloon dilation and to analyze the risk factors for secondary surgical failure in patients with recurrent uretero-pelvic junction obstruction (UPJO).MethodsWe retrospectively analyzed 65 patients with recurrent UPJO who underwent secondary surgery between September 2011 and March 2019, of whom 33 had complete baseline data and follow-up data. General clinical information, perioperative data, and follow-up results were collected from patients. Risk factors for surgical failure in patients with recurrent UPJO were analyzed using logistic regression.ResultsThe failure rates of secondary pyeloplasty and balloon dilation in secondary surgery were 16.7% and 33.3%, respectively. Univariate analysis showed that ureteral stenosis length and operative time were associated with secondary pyeloplasty and balloon dilatation failure (p < 0.05), and ureteral stenosis length was an independent risk factor for secondary pyeloplasty failure (OR = 0.074, 95% CI: 0.006–0.864, p = 0.038). In the balloon dilation group, treatment failure rates were significantly lower in patients with stenotic segment lengths less than 1 ± 0.32 cm than in patients with stenotic segment lengths greater than 1 ± 0.32 cm (p = 0.019).ConclusionsThe secondary pyeloplasty may provide better benefit. Ureteral stricture length is an independent risk factor for failure of secondary pyeloplasty and a potential risk factor for balloon dilatation. Operation time is a potential risk factor for pyeloplasty and balloon dilatation.

Sliding tracheoplasty of complete tracheal cartilage rings in children

IntroductionComplete tracheal rings are a rare malformation that occurs in 1 out of 100,000 live births. It is rare, isolated tracheal or tracheobronchial anomaly developed due to abnormal cartilage growth with formation of complete ring and often resulting in airway stenosis. Slide tracheoplasty, as it was originally described by Tsang et al. and popularized by Grillo et al., overlaps stenotic segments of trachea, shortening trachea itself, thus, doubling the circumference and diameter of the stenotic area. Materials and methodsWe have performed slide tracheoplasty in 12 children during the period of 2019–2021 in thoracic surgery department of our center. Median age was 15 ± 21,1 months (2 months-6 years),median weight – 8,04 ± 4,75 kg (3–20,7 kg),tracheal lumen varied from 2.5 to 3.0 mm, stenosis length – from 40 to 70% of the trachea length. ResultsSlide tracheoplasty was performed using central veno-arterial extracorporeal membrane oxygenation in 7 cases and using cardiopulmonary bypass in 5 cases. Concomitant heart disease was revealed in 5 children (pulmonary artery sling in 3 cases, ventricular septal defects – 1, aberrant subclavian artery −1). 5 children underwent one-stage correction of VSD: plastic VSD –1; left pulmonary artery reimplantation – 3; subclavian artery reimplantation – 1. All patients were on mechanical ventilation for 4,3 ± 2,78 days at postoperative period. Patients were discharged 16,3 ± 5,14 days after surgery. Satisfactory result of treatment in the form of respiratory failure relief was achieved in 10 patients. It was possible to increase the trachea lumen from 1.5 to 2 times in all cases. There were 2 (16,6%) fatal cases due to sepsis and multi-organ failure development. ConclusionsChildren with complete tracheal rings are very complicated patients with various comorbidities. Despite the advances in medicine, sometimes it is impossible to save lives of these children. The use of extracorporeal circulation (ECMO and bypass) allows us to safely perform reconstructive surgery on the trachea and save the child from respiratory failure manifestations. If needed, simultaneous correction of heart and tracheal defects is possible. Slide tracheoplasty allows to increase trachea lumen at least in 1.5–2 times. Mechanical ventilation is an unfavorable predictive factor for the outcomes of congenital tracheal stenosis management. Level of evidenceIII.

Residual anterior cord compression after laminoplasty for cervical spondylotic myelopathy: evaluation of risk factors according to the most severely stenotic vertebral segment.

Residual anterior spinal cord compression (RASCC) after cervical laminoplasty, which has been confirmed on postoperative MRI, is reportedly associated with poor clinical outcomes. To date, only a few studies have described the risk factors associated with RASCC. The aim of this study was to identify the factors that can predict the occurrence of RASCC after laminoplasty for cervical spondylotic myelopathy (CSM), focusing on the location of the most stenotic segment. In this retrospective, single-center study, 120 patients who underwent C3-7 laminoplasty for multilevel CSM were included. Different techniques were used for C3 decompression, i.e., partial (dome-laminotomy) or complete (laminoplasty/laminectomy) decompression. RASCC was diagnosed using MRI conducted 3 weeks postoperatively. The patients were divided into two groups according to the segment with the most severe stenosis (Seg-MSS; C3-4 vs C4-7). Demographics, radiological data, and C3 decompression technique were compared between the two groups. Furthermore, intergroup comparisons were performed based on Seg-MSS. A logistic regression model was constructed to identify the factors predicting RASCC after patient stratification according to Seg-MSS. Forty patients (33.3%) had RASCC. The patients with Seg-MSS at C3-4 (51.3%) had a significantly higher incidence of RASCC (p = 0.003) than those with Seg-MSS at C4-7 (24.7%). Logistic regression analysis showed that in patients with Seg-MSS at C3-4, C3 partial decompression demonstrated a greater association with RASCC as opposed to complete decompression. Conversely, in patients with Seg-MSS at C4-7, kyphotic segmental lordotic angle was associated with an increased risk of RASCC. The risk factors for RASCC differed depending on the location of the most stenotic segment (C3-4 vs C4-7). If there is segmental kyphosis at the most stenotic segment at C4-7, anterior decompression and fusion should be considered. If C3-4 is the most stenotic segment, anterior surgery is also recommended, but alternatively, one can choose laminoplasty with complete C3 laminectomy and resection of the C2-3 ligamentum flavum.

Systematic Review of Current Literature on Clinical Outcomes of Uniportal Interlaminar Contralateral Endoscopic Lumbar Foraminotomy for Foraminal Stenosis

Uniportal interlaminar contralateral endoscopic lumbar foraminotomy (ICELF) aims to achieve decompression of lumbar spinal stenosis in the contralateral lateral recess and foraminal and extraforaminal regions of the same segment. This technique is performed under normal saline irrigation using an endoscope with optical lens magnification close to the targeted stenotic segment and has the potential of lower incidence of exiting nerve root dorsal root ganglion irritation. A systematic review of the ICELF technique was conducted from March 2000 to March 2022. Articles were selected with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Eligibility of studies was independently determined by 2 reviewers, and disagreements were resolved by a third author. Eight retrospective cohort studies comprising 194 patients with foraminal stenosis who underwent uniportal ICELF were selected for systematic review. Mean age range was 62-79 years, and surgical duration was 48-73.5 minutes. There was significant improvement in Oswestry Disability Index and visual analog scale leg pain score in the included studies. Four studies met the minimum clinically significant difference for leg pain, with visual analog scale improved >5 points and Oswestry Disability Index improved >8.2 points. Four studies reported a majority of the operated patients with good or excellent outcomes following surgery, with a low rate of complications in the studies selected. There is low-level evidence that ICELF when performed by an experienced spinal endoscopic surgeon is effective in providing pain relief and improved function with low rate of complications in select patients.

Risk factors for celiac artery and superior mesenteric artery stenosis in preoperative lumbar and thoracolumbar spinal surgery patients

BackgroundIschemic necrosis of the abdominal organs caused by compression of the celiac artery (CA) and superior mesenteric artery (SMA) by the median arcuate ligament (MAL) after correction surgery has been recognized as acute celiac artery compression syndrome (ACACS). Here, using contrast-enhanced computed tomographic (CT) images, we sought to determine the prevalence and degree of CA and SMA stenosis in spinal patients preoperatively, and the risk factors associated with the stenosis. MethodsWe retrospectively examined contrast-enhanced abdominal CT of 90 patients with preoperative lumbar degenerative disease, lumbar burst fracture, or adult spinal deformity. The trunks of the CA and SMA were detected using three-dimensional reconstructed CT. To investigate their degree of stenosis, we determined the ratio of the narrowest diameter of the stenotic segment to the distal normal lumen's diameter. Patients with a degree of stenosis ≥35% were defined as being in the group with stenosis and the remainder as in the group without. To determine the risk factors for stenosis of these arteries, the relationship between the stenosis and CA and SMA calcification or the median arcuate ligament (MAL) crossing the proximal portion of the celiac axis (MAL overlap) was also investigated. ResultsThe average degree of stenosis of the CA trunk was 12.1% ± 13.9% and that for the SMA trunk was 8.5% ± 8.8%. There were 8 patients (8.9%) in the group with CA stenosis and 2 patients (2.2%) in the group with SMA stenosis. The number of patients in the group with CA stenosis was significantly greater than the number with MAL overlap or CA calcification (P < 0.05). DiscussionThe prevalence of CA or SMA stenosis was 11.2% of preoperative patients due to undergo thoracolumbar fusion surgery. Calcifications of the CA trunk and MAL overlap are risk factors for CA stenosis.

Percutaneous Nephrostomy in the Treatment of Hydronephrosis in Renal Transplant Patients - Case Report.

Percutaneous nephrostomy is a first-line minimal invasive treatment option for ureteral obstruction following kidney transplantation, with high effectiveness and a low complication rate. Percutaneous nephrostomy might be used as a temporary salvage therapy, providing acute decompression of the kidney collecting system and preventing graft loss. It can also function as a permanent and sometimes only possible option in transplant patients with frequent recurrences of ureteral stenosis who either fail an open surgical reconstruction or who are not good candidates for these procedures. We present two patients with acute decline in urine output after renal transplantation with radiologically verified hydroureteronephrosis of the transplanted kidney (graft) caused by stenosis of distal ureter. In both cases, nephrostomy was placed within 48 hours as a temporary salvage treatment that ameliorates renal function and prevents graft loss. The permanent nephrostomy was the only possible solution for the preservation of the graft's function in the first case because of the recurrences of ureteral stenosis after several percutaneous interventions and open-surgery ureteral reconstruction. A few episodes of nephrostomy tube-related infections were resolved with antibiotics in the first case. The second case was treated with open ureteroneocystostomy with resection of stenotic segment and reinsertion of the ureter into the bladder (ureterocystoneostomy) because of the length of the involved ureteral segment. Both patients had stable graft function in the follow-up period.

Cerebral Venous Sinus Stenting for the Treatment of Idiopathic Intracranial Hypertension in a Child

AbstractIdiopathic intracranial hypertension (IIH) is a disease characterized by an increase in the opening pressure of the cerebrospinal fluid (CSF) associated with symptoms of elevated intracranial pressure (ICP). The condition is more prevalent in women and typically managed clinically. Surgical treatment is reserved for select refractory cases. The well-established surgical procedures for the management of IIH are CSF shunting and fenestration of the optic nerve sheath. These procedures, however, are associated with high rates of complication and recurrence.More recently, venous sinus angioplasty with stents has been employed in cases with documented narrowing of the sigmoid-transverse sinuses. This technique is associated with a significant reduction in the venous pressure gradient at the stenosis site, alleviating the symptoms of intracranial hypertension.We report a case of a previously healthy 12-year-old patient who presented with 10-day history of headaches, blurring of vision, nausea and vomiting, which evolved with worsening of the visual acuity and papilledema. Imaging scans disclosed stenosis of the right transverse and sigmoid sinuses. The patient underwent stenting of the stenotic venous segments and showed good evolution, with significant clinical improvement within 24 hours of the procedure.

Effects of heat transfer, body acceleration and hybrid nanoparticles (Au–Al2O3) on MHD blood flow through a curved artery with stenosis and aneurysm using hematocrit-dependent viscosity

The present study investigates the heat transfer and body acceleration effects on unsteady MHD blood flow through a curved artery in the presence of stenosis and aneurysm using hybrid nanoparticles (). For realistic behavior of blood flow, blood is assumed to be a pulsatile, laminar, incompressible, viscous fluid with hematocrit-dependent viscosity. A uniform magnetic field is applied in the radial direction to the blood flow with radiation effect. The governing momentum and energy equations are solved using Crank-Nicolson Finite difference method through an accurate mesh using rectangular mesh units. The obtained data for both stenotic and aneurysm segments are graphically depicted and analyzed for various physical parameters. To examine the overall behavior of blood flow patterns, velocity contours for several emergent parameters have been displayed. Using clinically realistic hemodynamic data, comprehensive solutions for gold and gold- aluminium oxide hybrid mediated blood flow are presented. It is observed that the velocity profile rises as the volume fraction of gold () nanoparticles increases, while, the velocity profile decreases as the volume fraction of aluminium oxide () nanoparticles increases. It is noted that impedance of the flow decreases with increment in body acceleration parameter , while, WSS increases with increment in . The resistive impedance is higher for curved arteries than straight artery. The findings show that hybrid nanoparticles () reduce the values of hemodynamic parameters such as wall shear stress and resistive impedance, and blood flow rate decreases with an increment in and magnetic field strength. The current findings are consistent with recent findings in other studies. The outcomes of the study may be helpful in the diagnosis and treatment of plaque rupture, cancer, infections, brain aneurysms, and blood clot removal. Results may also be used to design and analyze biomedical devices for great potential treatment modalities, the anticancer drug industry, and nano-drug delivery systems.

P14.15: Early Preventive “Coronary Sealing” of Transmitted Coronary Artery Disease With Stent PTCA to Improve Outcomes of Heart Transplantation

Introduction: The prevalence of asymptomatic coronary atherosclerosis in the population is high, and the use of donor hearts from older individuals and “suboptimal” donors increases the likelihood of coronary artery disease (CAD) transmission to the heart recipients. Percutaneous transluminal coronary angioplasty (PTCA) with subsequent stenting improves angina symptoms but has no advantages over medical therapy in the “native heart” CAD patients. We hypothesize that early preventive coronary angioplasty would improve prognosis of the insensitive denervated donor hearts patients. Objectives: To study the impact of transmitted CAD and preventive angioplasty on the risk of death, re-transplantation, or the need for coronary revascularization in the long-term period after orthotopic heart transplantation (HT). Methods: All recipients who received the heart transplant at the Shumakov National Transplant Centre (Moscow, Russia) between January 2013 and December 2016 and survived 30 days after the surgery were included. Initial endomyocardial biopsy and coronary angiography were performed at the first week. Patients with >50% stenosis in the large branches of the coronary arteries were randomized to receive immediate PTCA or not. All-cause death, re-transplantation due to irreversible heart graft dysfunction, and the need for PTCA were used as a primary outcome composite endpoint. Results: A total of 431 HT were performed from 15.01.2013 to 29.12.2016; 389 (90.3%) patients have survived 30 days after HT; 10 (2.3%) patients who underwent repeated HT within 30 days were not included in the study. The primary coronary angiography revealed single or multiple stenoses <50% in 25 (6.6%) pts; 56 (14.9%) pts had significant >50% coronary stenosis, among them 24 random patients had the stent PTCA. During the follow-up period of 2112.1±146.0 (95% CI: 2022-2587) days, 42 (11.1%) patients died, the re-transplantation was performed in 9 (2.4%) cases, and PTCA was required in 61 (16.1%) cases. A Kaplan-Meier comparison showed a similar event-free survival rate in patients without initial changes in the coronary arteries, patients with <50% stenosis, and patients with >50% stenosis who underwent preventive PTCA, which was significantly better than had patients with >50% stenosis who did not undergo PTCA. Conclusion: The study showed that the presence of the occlusive (>50%) stenotic coronary segments in the donor’s heart has significant effect on event-free survival after HT and preventive PTCA of these segments improves the risk of death and re-transplantation while increases the likelihood of repeated coronary revascularization in the future.