Site Of Stenosis Research Articles

Endoscopic Management of Afferent Loop Syndrome: Case of Recurrent Gastric Cancer Leading to Pancreatitis and Gastric Outlet Obstruction

Introduction: Afferent loop syndrome (ALS) is a rare complication of Bilroth ll gastrojejunostomy. ALS occurs due to a mechanical obstruction of the afferent limb secondary to anastomotic site stricture, cancer recurrence, peritoneal metastasis, volvulus, intussusceptions, internal hernia, or abdominal adhesion after surgery. Case presentation: 82 years old woman with the history of stage lllc gastric adenocarcinoma underwent Billroth ll gastrectomy. One year later, the patient was admitted with pancreatitis and ALS that was managed conservatively. At that time, some overgrowth of tissue was noted at the gastrojejunostomy (GJ) anastomosis on EGD. However, the endoscope was easily passed to the afferent loop which was found to be distended and filled with food debris, suggestive of partial obstruction. 3 months later, while continuing her chemotherapy, patient presented with nausea, vomiting, and abdominal distension. CT scan also showed obstruction of the afferent limb which was markedly dilated. EGD confirmed recurrence of tumor at GJ anastomosis and significant narrowing at the entrance of the afferent loop. A 22mm, 9cm uncovered self-expandable metal stent (SEMS) was placed in the afferent loop. The proximal tip of the stent placed in the gastric pouch. Then a 22 mm, 12 cm uncovered SEMS was placed in the efferent loop, bridging the partial obstruction of GJ anastomosis. Proximal end of the stent was positioned just above gastroesophageal junction to reduce chance of migration. This method of stenting was performed to facilitate passage of food directly to the efferent loop. The afferent loop stent ending in the gastric pouch would decompress the afferent loop without causing obstruction of the efferent side. After the procedure, abdominal distension resolved, and the patient was able to eat without nausea or vomiting. Discussion: ALS can be managed surgically, endoscopically or percutaneously. However, surgical management is usually avoided if recurrence of malignancy is the etiology of ALS. Percutaneous placement of drainage catheter into the afferent loop, for decompression purposes, has the risk of leakage of enteric contents to the peritoneum and infection. Endoscopic management with placement of uncovered SEMS in the afferent loop, or in both loops, such as in this case with efferent and afferent loop obstruction, appears to be of less risk and excellent palliative choice in patients with recurrence of malignancy.2150_A Figure 1. Endoscopic image of Stent Placement in Afferent and Efferent Loops2150_B Figure 2. Fluoroscopic image of Stent Placement in Afferent and Efferent Loops2150_C Figure 3. Efferent loop stent tip at GE junction

NF-κB Decoy Oligodeoxynucleotide-Coated Balloon Catheter for Arteriovenous Fistula in Hemodialysis

IntroductionNew treatments to inhibit neointimal formation after percutaneous transluminal angioplasty (PTA) are needed for patients undergoing chronic hemodialysis (HD). We compared the efficacy and safety of AMG0102, a balloon catheter containing nuclear factor κB (NF-κB) decoy oligodeoxynucleotide (ODN) with the PTA balloon catheter (control group) for arteriovenous fistula (AVF) stenosis.MethodsIn total, 175 patients (age ≥20 years, undergoing HD, with venous stenosis at the anastomotic region) were registered in this prospective open-label, randomized study. Patients were followed postoperatively for 36 weeks. The duration of primary patency on the targeted venous stenosis site (primary endpoint) was estimated by the Kaplan–Meier method.ResultsA lower restenosis risk was observed for the AMG0102 group, but it was not statistically significant (stratified log-rank test P = 0.250, hazard ratio [HR] 0.774; 95% confidence interval [CI]: 0.500–1.198). The median duration of primary patency was 245 days and 172 days in the AMG0102 and control groups, respectively. After stratification based on the status of diabetes complications, the HR was 0.666 (95% CI: 0.366–1.212; P = 0.183) and the median duration of primary patency was prolonged by 108 days in the AMG0102 group with diabetes complications (245 days) compared with the control group (137 days). Adverse event (AE) incidence up to 36 postoperative weeks did not differ between groups. Four device failures occurred in 3 patients (AMG0102 group), but none resulted in AEs.ConclusionFurther modifications to enhance NF-κB decoy ODN uptake and efficacy are necessary to show its clinical utility for AVF stenosis in chronic HD.

Role of the gonadal vessels on the stone lodgment in the proximal ureter: Direct observation during laparoscopic ureterolithotomy.

Previous radiological studies revealed that stones lodge more frequently in the ureterovesical junction (UVJ) as well as the proximal ureter. Factors that prevent stone passage from the proximal ureter are not well studied. To explore the site of the lodged stones in the proximal ureter with direct observation during laparoscopic ureterolithotomy. Between November 2014 and February 2015, we included 26 patients including 18 men and 8 women with stones larger than 10 millimeters in the proximal ureter who were candidate for laparoscopic ureterolithotomy. We prospectively recorded the site of the lodged stones in the ureter during laparoscopic ureterolithotomy in relation with the sites of ureteral stenosis as well as the gonadal vessels. Among 26 patients with ureteral stone, in 19 cases stone was found close to the gonadal vein compared with seven cases that stone was in other locations of the ureter (p = 0.02). The characteristics of patients and stones were not different in cases that the stone was close to gonadal vessels compared with other locations. This study showed that most of the stones lodged in the proximal ureter were in close proximity with gonadal vessels. Gonadal vessels may be an extrinsic cause of ureteral narrowing.

Initiation of Arterial Stenotic Thrombosis

Current practice in arterial disease is to establish the site of stenosis, to dilate the stenosis with angioplasty or surgical bypass, and to try to maintain the integrity of the arterial lumen with stents. There are either bare stents or drug eluting stents which are more thrombogenic requiring long term dual antiplatelet therapy with its risk of increased bleeding. For coronary disease, this is called Percutaneous Coronary Intervention (PCI).

Treatment of congenital distal ureteral orifice stenosis by endoscopic laser ablation in dogs: 16 cases (2010-2014).

OBJECTIVE To determine characteristics of and outcomes for dogs with congenital distal ureteral orifice stenosis (CDUOS) treated by cystoscopic-guided laser ablation (CLA). DESIGN Retrospective case series. ANIMALS 16 client-owned dogs with CDUOS treated by CLA at 2 veterinary hospitals between 2010 and 2014. PROCEDURES Medical records were reviewed and data collected regarding clinical findings, imaging results, surgery characteristics, treatment, and outcome. Follow-up information was collected from dog owners and referring veterinarians via standardized interview. RESULTS Dogs included 10 males and 6 females; median age was 11.5 months (range, 4 to 112 months). Labrador Retriever (n = 6; 3 males) was the most common breed. Intramural ectopic ureteral openings were identified at the site of stenosis in 15 dogs (18/20 stenotic ureteral openings). Treatment with CLA to enlarge and relocate the stenotic opening was successful in all dogs. Median duration of anesthesia and hospitalization was 105 minutes and 24 hours, respectively. No complications were noted. Fourteen dogs remained alive (2 lost to follow-up) during a median follow-up period of 14.5 months. Owners of 11 of 13 dogs reported improvement in their dog's quality of life after CLA. The treated ureteral orifice remained patent in the 2 dogs that were reimaged. CONCLUSIONS AND CLINICAL RELEVANCE CDUOS should be considered as a differential diagnosis for dogs with idiopathic distal ureteral obstruction, particularly young male Labrador Retrievers, and was most often associated with an intramural ectopic ureter in this study. Treatment with CLA was safe and effective for opening the ureteral orifice.

An open-label, single-arm study of CRYO2 for tissue removal at the site of central airway obstruction or stenosis: study protocol.

ABSTRACTArgon-plasma coagulation, high-frequency electrosurgical snare, laser therapy, and microwave treatment are therapeutic options to reduce tumor-related stenosis of the central airway. These treatments may cause airway fire under a high concentration of oxygen, so FiO2 levels must be ≤40%. This restriction may be dangerous when treating patients with respiratory failure. The cryosurgery unit, ERBE-CRYO2, facilitates treatment under an FiO2 level of 100%, safely reducing this risk. In Japan, CRYO2 has been approved for cryobiopsy and foreign body removal, but not for tissue removal at the site of obstruction or stenosis due to lack of sufficient evidence. Since CRYO2 may be useful for reducing airway stenosis, the present study was designed to increase indications for this unit in Japan.

Endovascular Management for Salvage of Failing Arteriovenous Fistula

Background: Failure of arteriovenous access for hemodialysis is a challenging problem. Maintaining the patency of this access is one of the most important corner stones in the care of patients with chronic renal failure. Recently, percutaneous transluminal balloon angioplasty (PTA) is considered the first line of treatment for dealing with this issue. Aim: The purpose of this retrospective observational study was to evaluate the primary and secondary patency rates after initial endovascular intervention to restore and preserve the patency of failing autogenous arteriovenous fistulae and to identify the potential factors that affect the durability of the procedure. Methods:The results of 56 patients with failing autogenous arteriovenous fistulae were retrospectively analyzed after being treated with percutaneous transluminal balloon angioplasty from November 2014 to December 2018. Technical & clinical success rates were reported. The variables, including patients’ demographics, co-morbidities, medications, fistula age, fistula type, site, number of lesions and degree of stenosis were analyzed and correlated with primary and secondary patency rates. Results: The mean age of the fistulae included in the study since their creation was 17.4 ± 9.6 months, most of which were radiocephalic fistulas (64.3%). The most common cause of autogenous access dysfunction was 90-99% stenosis while the most common site of stenosis was juxta-anastomotic. Technical and clinical success rates of the study population were 92.9% and 89.3%, respectively. The mean primary and secondary patency were 12.3 and 19.9 months, respectively. Primary patency rates at 6,12,18 and 24 months were 79%, 64%, 57% and 44% respectively. Secondary patency rates at 6,12,18 and 24 months were 85%, 76%, 68% and 52% respectively. Patient age ≥ 60 years old was associated with reduced post-PTA primary patency (P < 0.001) and secondary patency (P = 0.018). Dyslipidemia showed marked decrease in both primary and secondary patency rates (P < 0.001). Insulin intake (P < 0.001) was a predictor of primary patency decrease while use of antiplatlets was to a less extent predictor of secondary patency loss (P = 0.004). Radiocephalic fistulae had short primary patency (P = 0.016), while stenotic lesions > 90% showed a significant decrease (P < 0.001) in primary patency more obvious than with secondary patency (P = 0.006). Lesions at arteriovenous anastomosis were significantly associated with decrease in primary patency (P < 0.001). Statins were the only medications associated with longer primary patency (P < 0.001). Age of fistula and number of lesions were independent factors. Conclusion: Endovascular treatment is both safe and effective in managing failing autogenous arteriovenous fistulas. Although its technical and success rates are high, primary and secondary patency rates are still questionable. Dyslipidemia, insulin, statin and antiplatelet intake together with age of patient, degree and site of stenosis are potential risk factors that affect these rates.

Thrombectomy Using Myocardial Biopsy Forceps in Acute Limb Ischemia Patients

PurposeTo evaluate the efficacy and safety of thrombectomy using myocardial biopsy forceps for the treatment of acute limb ischemia (ALI). Materials and MethodsA retrospective review of 11 ALI patients (12 affected limbs, 18 affected vessels) who underwent thrombectomy using biopsy forceps between November 2011 and April 2016 was performed. Of the 12 affected limbs, 2 limbs had stent thrombosis, 1 limb had thrombotic occlusion at a de novo stenosis site, and 9 limbs had embolic ALI. Biopsy forceps were used for angiographically limited arterial flow that persisted after the use of an aspiration catheter and conventional balloon angioplasty. The general technique for use of the biopsy forceps included advancement in parallel to a guidewire to the thrombus site, grasping of the thrombus with the forceps, and confirmation of grasping the thrombus with injection of a contrast medium prior to thrombus extraction. ResultsPartial or total retrieval of the thrombus was angiographically confirmed in 12 of the 18 affected vessels, with restoration of normal blood flow in 11 vessels. Unsuccessful results in the remaining 6 affected vessels appeared to be due to friction at the aortoiliac bifurcation caused by the contralateral approach, small vessel size, or curvature of the anterior tibial artery. None of the 18 treated vessels had any complications such as dissection or perforation of the target vessel wall and distal emboli. None of the surviving patients required major or minor amputation. ConclusionsThrombectomy using biopsy forceps is a feasible technique for removal of an arterial thrombus in patients with ALI.

Study of Enzymes in Myocardial Infarction

The term Myocardial infarction signifies sudden necrosis or death of a portion of cardiac muscle due to inadequate blood supply [1]. Myocardial infarction results from prolonged myocardial coronary thrombus at the site of a pre-existing atherosclerotic stenosis [2].

Abstract 090: Slc44a2 Deficient Mice Exhibit Less Severity of Thrombosis in a Stenosis Model of Deep Vein Thrombosis

Background/Objective: Recent genome wide association studies identified SLC44A2 as a novel susceptibility locus for venous thromboembolism (VTE), a region encoding the solute carrier family 44 member 2 protein (SLC44A2). Here we utilize Slc44a2 deficient mice (KO) to determine the importance of SLC44A2 in thrombotic disease. Methods: Mice lacking Slc44a2 were included in two models of venous thrombosis: 1) a spontaneous thrombosis model using siRNA targeting anti-coagulants Serpinc1 and Proc and 2) a model of deep vein thrombosis (DVT) induced by flow restriction (stenosis) of the inferior vena cava (IVC). Results: In the model of spontaneous thrombosis, Slc44a2 deficiency did not affect incidence as occurrence of thrombotic phenotype reached 100% in both wild type (WT; 12/12) and KO (12/12) mice 32 hours after siRNA injection. Platelet counts and fibrin deposition in the liver were also comparable. However, levels of circulating neutrophils were significantly higher (p=0.0017) in KO mice along with substantially lower amounts of plasma VWF antigen (p&lt;0.0001). As these findings suggested a link between SLC44A2 and neutrophil function, a DVT model previously determined to be neutrophil dependent, was also employed. After 48 hours of IVC stenosis, 100% of the WT mice developed an occlusive thrombus (10/10) whereas 80% of the mice lacking Slc44a2 did (12/15). Thrombus length was significantly reduced in KO animals (p=0.0184), as was thrombus weight (p=0.0413). Immunhistochemical staining of the thrombi revealed different repartitions in the “white” (platelet-rich) over the “red” (RBC-rich) parts of the thrombi depending on the mouse genotype. This observation suggests a different blood cell mobilization at the site of stenosis depending of the genotype. Plasma VWF levels were correlated with thrombus weight in WT (p=0.0175), but not in KO mice (p=0.3266), and had been previously confirmed to be lower in KO mice. Conclusion: These findings corroborate the original GWAS data, indicating a role for SLC44A2 in thrombotic disease. We have observed that SLC44A2 was not involved in a platelet-dependent model of thrombosis whereas it is involved in a thrombosis model where neutrophils and VWF have been shown to play a crucial role.

Settlement of Stenotic Site and Enhancement of Risk Factor Load for Atherosclerosis in Left Anterior Descending Coronary Artery by Myocardial Bridge.

The aim of this study was to investigate the influence of a myocardial bridge (MB) on atherosclerosis development in the left anterior descending artery of the normal heart and the importance of traditional risk factors (RFs). An additional objective was to determine the correlation between intimal thickening and luminal narrowing. The left anterior descending artery from 150 autopsied hearts was treated with formalin perfusion fixation, and each left anterior descending artery was serially cross-sectioned. The intima-media and luminal stenosis ratios were examined using computer-assisted histomorphometry. The luminal stenosis ratio was closely correlated with the intima-media ratio (r=0.792; P<0.001). When an MB was present, the luminal stenosis ratios proximal to the MB in the RF (+) group were significantly greater than those in the RF (-) group (P=0.022 by a multiple comparison test), but there were no differences between the RF (+) and RF (-) groups when an MB was absent. In addition, the site of the greatest stenosis in the MB (+) RF (+) group was 2.5 cm proximal to the MB entrance. Multivariate analyses indicated that age was an independent factor for luminal stenosis ratios ≥50% and 60% (P=0.002 and 0.029, respectively). Furthermore, the presence of an MB plus RFs was an independent factor for a luminal stenosis ratio ≥70% (P=0.037). An MB enhances left anterior descending artery atherosclerosis development at a site proximal to the MB entrance, particularly in subjects who have some RFs.

Early experiences of intraoperative ultrasound guided angioplasty of the arterial stenosis during upper limb arteriovenous fistula creation.

In recent years the high prevalence of diabetes and atherosclerosis in elderly uremic patients starting hemodialysis (HD) has led to the increase in the risk of vascular access (VA) failure caused by pre-existing arterial diseases, including both VA slow maturation and early failure, and upper limb ischemic symptoms. Recently, in performing radial (R), brachial (B) and ulnar (U) artery (A) percutaneous transluminal angioplasty (PTA) in HD patients affected by access thrombosis, with insufficient blood flow and severe upper limb ischemia, good outcomes have been reported. Nevertheless, these procedures were performed after arteriovenous fistula (AVF) creation. About 2 years ago, we approached an intra-operative ultrasound-guided transluminal angioplasty (IUTA) performed during AVF creation, using the arterial incision, necessary because of the anastomosis, to introduce the necessary devices for the IUTA. The arterial stenosis having undergone IUTA was diagnosed by a preliminary ultrasound examination. Ultrasound guidance during the procedure is necessary for correct balloon location in the stenosis site. We treated seven patients (four diabetics), mean age 76 + 5 yrs. In all cases, the radial arteries because of hyposphygmia, were unfit for AVF creation. Four distal radio-cephalic AVFs at the wrist were created in patients 1, 3, 4 and 5; in the other three patients (2, 6 and 7), with failure or thrombosis of previous distal AVFs, an immediately upstream anastomosis was performed. In all cases, first, the area selected to perform the AV anastomosis was exposed, then the AR was incised, and the introductory metallic guide wire and the angioplasty catheter (with dimensions decided after PUS), were introduced. The balloon was inflated to 8-13 atm for 30-35 sec. In two patients a stent was also positioned. Later, a side-to-side AVF was created, closing the distal venous vessel. Patient follow-up ranged from 6-22 months. The ultrasound evaluation after IUTA showed the correction of all the stenosis treated. AVF maturation was good, except for the stented ones, which were inadequate. In conclusion, our early experience shows IUTA could be an adequate and effective procedure allowing the use of the stenotic arteries (otherwise unsuitable) for AVF creation. In our experience, stenting after IUTA does not add any other advantages.

Endovascular Treatment of Duplicated Inferior Vena Cava Compression From Retroperitoneal Fibrosis

Retroperitoneal fibrosis (RPF) is a rare condition that can affect the iliocaval veins, leading to treatment of this condition. We report a unique case of RPF causing symptomatic compression of a duplicated inferior vena cava treated successfully with stenting. A 68-year-old African American man presented for evaluation of severe debilitating venous claudication and bilateral lower extremity swelling. He reported chronic and progressive symptoms of venous insufficiency that became lifestyle limiting a few months before presentation. His past medical history was significant for hypertension, anemia, and idiopathic RPF with mild renal insufficiency. His surgical history was significant for retroperitoneal exploration and ureterolysis for left-sided hydronephrosis as well as bilateral hydrocele resection. On physical examination, he had normal pulses and severe edema, right worse than left, but no varicosities. Duplex ultrasound was negative for deep venous thrombosis or reflux but demonstrated blunting of respiratory variations in the bilateral external iliac veins. Computed tomography scan showed near obliteration of the venous structures in the pelvis (Fig 1, A). The patient was fitted for compression stockings but could not get relief. Venography was performed and demonstrated a duplicated inferior vena cava with severe bilateral stenosis of the iliocaval vasculature (Fig 2). Intravascular ultrasound was performed to confirm the sites of stenosis and for sizing. Bilateral balloon angioplasty and iliocaval stenting were performed using two 16-mm Wallstents (Boston Scientific, Marlborough, Mass) on the right and two 14-mm Wallstents on the left. The completion venogram showed excellent flow bilaterally (Fig 3). Intravascular ultrasound confirmed complete resolution of all areas of stenosis. The patient was started on clopidogrel and was discharged the next day. The edema cleared within a week, and he experienced excellent relief of symptoms. After 1 year, he was switched to aspirin, and he continues to have minimal symptoms with no recurrence. On his latest follow up, 33 months after intervention, computed tomography scan demonstrated patent stents in the duplicated cava and no venous stenosis (Fig 1, B). Iliocaval compression from RPF is rare but can be debilitating. Endovascular stenting seems to be an effective and durable treatment.Fig 2Pelvic venogram demonstrating severe stenosis in the right (A; arrow) and left (B; arrow) iliocaval systems.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig 3Completion venogram after iliocaval stenting showing brisk flow and resolution of areas of stenosis on the right (A) and left (B).View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Percutaneous Management of Biliary Enteric Anastomotic Strictures: An Institutional Review.

PurposeStricture formation at the biliary enteric anastomotic site is a common complication due to fibrotic healing. Few therapeutic options are available for biliary-enteric anastomotic site stricture (BES) including new surgical reconstruction or percutaneous transhepatic biliary drainage followed by balloon dilation of BES or stent placement. The purpose of this study is to assess the technical success, complications and reintervention rate of percutaneous transhepatic balloon dilatation (PTBD) of BES after iatrogenic bile duct injuries (BDI).MethodsA retrospective review of patients who underwent PTBD for benign resistant BES, previously treated for iatrogenic BDI, from December 2004 to January 2016 was performed. Diagnostic transhepatic cholangiogram was performed to assess the level of obstruction. BES was dilated using 8-12 mm diameter balloons followed by placement of eight to ten Fr internal-external drainage catheters, which were removed after three to six weeks post-PTBD cholangiogram. Follow-up by clinical assessment, liver function tests, and ultrasound was done. Fischer exact test was used to determine if there was a significant association between PTBD sessions and recurrent strictures.ResultsIn total, 37 patients underwent 66 sessions of PTBD, including 10 (27%) males and 27 (73%) females. The mean age was 41.3 years (range 23–70 years). Out of these, 29 (78%) were treated with choledochojejunostomy and eight (22%) with hepaticojejunostomy. 100% technical success was achieved in all the PTBD sessions. Nineteen (51.3%) patients were treated with a single PTBD session. Mean follow-up time was 36 months (range 1–75 months). Eighteen (48.7%) patients needed reintervention, out of these, 11 (29.7%) were symptom-free after second session on three-year follow-up, three (8%) were symptom-free after the third session of PTBD. No significant difference was observed in risk of recurrent strictures after first and second PTBD sessions [18 (48%) vs. 7 (39%); p-value 0.495]. In four (11%) patients, the symptoms persisted and BES recurred even after third session and those were treated by placing metallic stent. In total, three (8.1%) patients got complicated with the stone formation; in two (5%) patients stone was successfully removed percutaneously and in one (3%) patient percutaneous attempt failed so it was followed by surgical removal.ConclusionPTBD is a safe and useful treatment option for benign BES for long-term symptom-free time-period. However, there is no significant difference in developing recurrent BES after PTBD sessions. Few patients with resistant strictures might require stent placement.

Stenting for Symptomatic Vertebral Artery Stenosis: The Vertebral Artery Ischaemia Stenting Trial

Objective: To compare in the Vertebral Artery Ischaemia Stenting Trial (VIST) the risks and benefits of vertebral angioplasty and stenting with best medical treatment (BMT) alone for symptomatic vertebral artery stenosis. Methods: VIST was a prospective, randomized, open-blinded endpoint clinical trial performed in 14 hospitals in the United Kingdom. Participants with symptomatic vertebral stenosis ≥50% were randomly assigned (1:1) to vertebral angioplasty/stenting plus BMT or to BMT alone with randomization stratified by site of stenosis (extracranial vs intracranial). Because of slow recruitment and cessation of funding, recruitment was stopped after 182 participants. Follow-up was a minimum of ≥1 year for each participant. Results: Three patients did not contribute any follow-up data and were excluded, leaving 91 patients in the stent group and 88 in the medical group. Mean follow-up was 3.5 (interquartile range 2.1–4.7) years. Of 61 patients who were stented, stenosis was extracranial in 48 (78.7%) and intracranial in 13 (21.3%). No periprocedural complications occurred with extracranial stenting; 2 strokes occurred during intracranial stenting. The primary endpoint of fatal or nonfatal stroke occurred in 5 patients in the stent group vs 12 in the medical group (hazard ratio 0.40, 95% confidence interval 0.14–1.13, p = 0.08), with an absolute risk reduction of 25 strokes per 1,000 person-years. The hazard ratio for stroke or TIA was 0.50 (p = 0.05). Conclusions: Stenting in extracranial stenosis appears safe with low complication rates. Large phase 3 trials are required to determine whether stenting reduces stroke risk. ISRCTN.com identifier: ISRCTN95212240. Classification of evidence: This study provides Class I evidence that for patients with symptomatic vertebral stenosis, angioplasty with stenting does not reduce the risk of stroke. However, the study lacked the precision to exclude a benefit from stenting.

Cephalic vein transposition is a durable approach to managing cephalic arch stenosis.

The proximal cephalic vein that enters the axillary vein (cephalic arch) is a common site of stenosis in patients with upper extremity arteriovenous fistulas for hemodialysis (HD). In this study, we present the outcomes of a series of cephalic vein transposition, to determine its utility in the setting of refractory arch stenosis. We conducted a retrospective review of patients undergoing cephalic vein transposition to manage refractory cephalic arch stenosis from January 1, 2008 to August 31, 2015. Demographics, past medical history, access history of the patients as well as procedural details of the surgery to the stenotic segment, patency of the access, and the need for subsequent interventions were recorded. Twenty-three patients underwent a cephalic vein transposition during the study period. The patients undergoing cephalic transposition had their current access for an average of 3.0 ± 2.6 years and had an average of 2.3 ± 0.9 interventions on the access prior to the surgery. Complications from the surgery were uncommon (8.7%) and no patient required a temporary tunneled dialysis catheter. The re-intervention rate was 0.2 ± 0.2 interventions per patient per year. At two years, primary patency was 70.9% and cumulative patency was 94.7% for the patients with cephalic transposition. Cephalic vein transposition is safe and effective treatment for cephalic arch stenosis without interrupting utilization of the access. The surgical approach to stenosis of the proximal cephalic vein is effective, requires minimal re-interventions, and should be considered for isolated, refractory cephalic arch stenosis in mature arteriovenous fistulas.

Scarring Airway Stenosis in Chinese Adults: Characteristics and Interventional Bronchoscopy Treatment.

Background:Scarring airway stenosis is commonly seen in China as compared to other developed countries, due to the high prevalence of tuberculosis. Nowadays, interventional bronchoscopy treatment has been widely used to treat this disease in China. This study demonstrated the characteristics of scarring airway stenosis in Chinese adults and retrospectively evaluated the efficacy of interventional bronchoscopy treatment of this disease.Methods:Patients with scarring airway stenosis from 18 tertiary hospitals were enrolled between January 2013 and June 2016. The causes, site, and length of scarring airway stenosis were analyzed, and the efficacy of the interventional bronchoscopy treatment was evaluated.Results:The final study cohort consisted of 392 patients. Endotracheobronchial tuberculosis (EBTB) was the most common cause of scarring airway stenosis (305/392, 77.8%) in Chinese adults with a high rate of incidence in young women. The left main bronchus was most susceptible to EBTB, and most posttuberculosis airway scarring stenosis length was 1.1–2.0 cm. The average clinical success rate of interventional bronchoscopy treatment for scarring airway stenosis in Chinese patients is 60.5%. The stent was inserted in 8.7% scarring airway stenosis in China.Conclusions:Scarring airway stenosis exhibits specific characteristics in Chinese patients. Interventional bronchoscopy is a useful and safe treatment method for the disease.

Assessment of the Correlation Between Carotid Artery Plaque Density Determined by Histogram Analysis and Positive Remodeling on Computerized Tomography Angiography

Background: CT angiography (CTA) was routinely performed for carotid artery disease, but the plaque characterization based on measurement of density may be inaccurate, influenced by adjacent calcification and contrast agent. Remodeling ratio was one of the additional new objective indexes for plaque characterization. On coronary CTA, the utility of histogram analysis was reported in a few studies. Objectives: The purpose of this study was to evaluate the diagnostic value of histogram analysis of carotid artery plaque density and positive remodeling on CTA for the diagnosis of pathologically proven complicated carotid artery plaques. Patients and Methods: We retrospectively evaluated 29 patients with atherosclerotic carotid artery stenosis treated by carotid endarterectomy. On CTA, the boundaries of non-calcified plaques were manually traced at the site of the greatest stenosis. In addition to the mean plaque density, the percentage of pixels (PP) with a density of less than 30 Hounsfield units (HU) (PP < 30) was calculated using the histogram analysis. We calculated the remodeling ratio by dividing the cross-sectional artery area at the greatest stenosis by normal reference-segment artery area. These results of CTA analysis were compared with the results of histological analysis based on the American heart association criteria. Results: Histologically, 13 of the 29 patients had complicated plaques. PP < 30 and the remodeling ratio were higher in patients with complicated plaques than in those with uncomplicated plaques (P = 0.023 and 0.002, respectively). Whereas, the mean plaque density did not differ between the two groups (P = 0.062). Correlation between PP < 30 and the remodeling ratio was stronger than the correlation between PP < 30 and the mean density (Spearman’s rs = 0.76 vs. 0.65, respectively). Conclusion: Histogram analysis of the carotid artery plaque density may be more useful for the evaluation of atherosclerosis on CTA compared with the conventional analysis of plaque densities, and the combined analysis of histogram analysis and the remodeling ratio may help to predict future stroke events.

Robot resection of a choledochal cyst with Roux-en-y hepaticojejunostomy in adults: Initial experiences with 22 cases and a comparison with laparoscopic approaches.

Backgrounds/AimsIn adult choledochal cysts, complete excision of cyst with Roux-en-Y hepaticojejunostomy by laparoscopy is typically been performed, but there is now a trend towards adopting robot-assisted resection.MethodsFrom January 2014 to December 2017, 22 patients who underwent robotic procedure were classified as Group 1, and 34 patients who underwent the same laparoscopic procedure as Group 2. In addition, from September 2009 to July 2011, 13 patients who underwent laparoscopic procedure were classified as Group 3. The perioperative outcomes and short-term postoperative morbidity levels were evaluated in three groups.ResultsIn all groups, there were more women than men, and the mean age and BMI did not differ significantly. Since 2014, jejunojejunostomy was performed extracorporeally and the mean operation time was shorter in Group 1 (258.5±52.9 min) and Group 2 (236.2±62.9 min) than Group 3 (395.2±85.9 min). [p=0.00 (1 vs 3), 0.00 (2 vs 3)] The median hospital stay was 7 days in Group 1 and 2, and shorter than 9 days in Group 3. [p=0.00 (1 vs 3), 0.011 (2 vs 3)] In Group 1, there were three postoperative complications, which included cholangitis, bile leakage and umbilical herniation, respectively). In Group 2, there were seven of postoperative complications, which included choledochojejunostomy site stricture & intrahepatic duct stone, choledochojejunostomy site stone, jejunal branch bleeding, portal vein thrombus, acute pancreatitis, adhesive ileus, and A-loop syndrome. In Group 3, there were three of postoperative complications, which included 2 hepaticojejunostomy site stricture and 1 paralytic ileus.ConclusionsRobot-assisted resection of a choledochal cyst with Roux-en-y hepaticojejunostomy is a safe and feasible approach with short-term results that are comparable to those of laparoscopic surgery.

Generalized Regression Estimator Improved the Accuracy Rate of Estimated Dialysis Accesses Stenotic Condition on In-Vitro Arteriovenous Graft Experimental Model

Dialysis vascular accesses are critical for patients receiving hemodialysis treatment. However, dialysis access stenosis and further dysfunction are engendered by thrombosis or outflow (venous anastomosis site) stenosis and the progression of inflow (arterial anastomosis site) stenosis. Thus, any narrowed access causes vibrations, turbulent flow, and murmur sounds around stenosis sites. Auscultation and frequency-based techniques are employed to detect these sounds, and frequency components are also validated on the basis of the degree of stenosis (DOS). In this paper, a biophysical experimental model employing an in vitro arteriovenous graft model was established to produce various acoustic signals associated with single stenosis and multiple stenoses. By analyzing various combinations of stenoses, this paper selected suitable features of the frequency and power spectra using the Burg autoregressive method. A multiple regression model applying a higher number of explanatory variables and response variables, as a generalized regression neural network, was employed to identify DOS levels at inflow and outflow sites. The experimental results indicated that the proposed screening model provided a higher average hit rate of >90%, average true-positive rate of >90%, and true-negative rate of 100% in single and multiple stenosis screening, compared with the multiple linear regression model.