Postprocedural microembolic events following carotid surgery and carotid angioplasty and stenting

OBJECTIVE: The relative safety of percutaneous carotid interventions remains controversial. Few studies have used diffusion-weighted magnetic resonance imaging (DW-MRI) to evaluate the safety of these interventions. We compared the incidence and distribution of cerebral microembolic events after carotid angioplasty and stenting (CAS) with distal protection to standard open carotid endarterectomy (CEA) using DW-MRI. METHODS: From November 2004 through August 2006, 69 carotid interventions (27 CAS, and 42 CEA) were performed in 68 males at a single institution. Pre- and postprocedure DW-MRI exams were obtained on each patient undergoing CAS and the 20 most recent CEA operations. These 46 patients (47 procedures as one patient underwent bilateral CEAs in a staged fashion) constitute our study sample, and the hospital records of these patients (27 CAS and 20 CEA) were retrospectively reviewed. The incidence and location of acute, postprocedural microemboli were determined using DW-MRIs and assessed independently by two neuroradiologists without knowledge of the subjects' specific procedure. RESULTS: Nineteen CAS patients (70%, 95% confidence interval [CI]: 42%-81%) demonstrated evidence of postoperative, acute, cerebral microemboli by DW-MRI vs none of the CEA patients (0%, 95% CI: 0%-17%) (P < .0001). Of the 19 CAS patients with postoperative emboli, nine (47%) were ipsilateral to the index carotid lesion, three (16%) contralateral, and seven (36%) bilateral. The median number of ipsilateral microemboli identified in the CAS group was 1 (interquartile ranges [IQR]: 0-2, range 0-21). The median number of contralateral microemboli identified in the CAS group was 0 (IQR: 0-1, range 0-5). Three (11%) CAS patients experienced temporary neurologic sequelae lasting less than 36 hours. These patients suffered 12 (six ipsilateral and six contralateral), 20 (19 ipsilateral and one contralateral), and zero microemboli, respectively. By univariate analysis, performing an arch angiogram prior to CAS was associated with a higher risk of microemboli (median microemboli 5 vs none, P =.04) CONCLUSIONS: Although our early experience suggests that CAS may be performed safely (no permanent neurologic deficits following 27 consecutive procedures), cerebral microembolic events occurred in over two-thirds of the procedures despite the uniform use of distal protection. Open carotid surgery in this series seems to offer a lower risk of periprocedural microembolic events detected by DW-MRI.     

Fibrin sheath removal from central venous catheters: an internal snare manoeuvre.

BACKGROUND: Dysfunction of haemodialysis catheters is most commonly due to a narrowing of the catheter lumen and/or formation of a fibrin sheath around the catheter tip. Reported methods for restoring patency of the catheter lumen include passage of a J-tipped guide wire, passage of a biopsy brush through the catheter, or infusion of a thrombolytic agent into the catheter. While these methods are often effective, they suffer from several limitations. We present a minimally invasive technique to remove thrombi and debris from within the lumen of a partially thrombosed haemodialysis catheter while simultaneously stripping the fibrous sheath. METHODS: A 0.089 cm nitinol wire is bent to create a loop, which is then inserted via the catheters. Upon exiting the lumen of the catheters, the nitinol wire forces a snare open, which disrupts the fibrin sheath and catches intraluminal thrombi and debris. The technique requires no anaesthesia or recovery time. RESULTS: Initial clinical success in our series was achieved in all patients (7/7) as evidenced by restoration of target flow rates on subsequent haemodialysis. None of the patients experienced any complications as a result of the procedure. The catheter 2-, 4-, and 6-week primary success rates were 100% (8/8), 100% (8/8), and 100% (8/8) respectively with a mean duration of 17.1 weeks (range 8-40 weeks). CONCLUSIONS: The internal snare technique is an effective, inexpensive and minimally invasive approach to restoring patency to failed central venous access catheters.     

Prostate cancer detection upon transrectal ultrasound-guided biopsy in relation to digital rectal examination and prostate-specific antigen level: what to expect in the Chinese population?

We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.     

Declines in violence and police arrest among female sex workers in Karnataka state,south India,following a comprehensive HIV prevention programme

Introduction

Female sex workers (FSWs) frequently experience violence, harassment and arrest by the police or their clients, but there is little evidence as to the impact that such factors may have on HIV risk or whether community interventions could mitigate this impact.

Methods

As part of the evaluation of the Avahan programme in Karnataka, serial integrated behavioural and biological assessment (IBBA) surveys (four districts) (2005 to 2011) and anonymous polling booth surveys (PBS) (16 districts) (2007 to 2011) were conducted with random samples of FSWs. Logistic regression analysis was used to assess 1) changes in reported violence and arrests over time and 2) associations between violence by non-partners and police arrest and HIV/STI risk and prevalence. Mediation analysis was used to identify mediating factors.

Results

5,792 FSWs participated in the IBBAs and 15,813 participated in the PBS. Over time, there were significant reductions in the percentages of FSWs reporting being raped in the past year (PBS) (30.0% in 2007, 10.0% in 2011, p<0.001), being arrested in the past year [adjusted odds ratio (AOR) 0.57 (0.35, 0.93), p=0.025] and being beaten in the past six months by a non-partner (clients, police, pimps, strangers, rowdies) [AOR 0.69 (0.49, 0.95), p=0.024)] (IBBA). The proportion drinking alcohol (during the past week) also fell significantly (32.5% in 2005, 24.9% in 2008, 16.8% in 2011; p<0.001). Violence by non-partners (being raped in the past year and/or beaten in the past six months) and being arrested in the past year were both strongly associated with HIV infection [AOR 1.59 (1.18, 2.15), p=0.002; AOR 1.91 (1.17, 3.12), p=0.01, respectively]. They were also associated with drinking alcohol (during the past week) [AOR 1.98 (1.54, 2.53), p<0.001; AOR 2.79 (1.93, 4.04), p<0.001, respectively], reduced condom self-efficacy with clients [AOR 0.36 (0.27, 0.47), p<0.001; AOR 0.62 (0.39, 0.98), p=0.039, respectively], symptomatic STI (during the past year) [AOR 2.62 (2.07, 3.30), p<0.001; AOR 2.17 (1.51, 3.13), p<0.001, respectively], gonorrhoea infection [AOR 2.79 (1.51, 5.15), p=0.001; AOR 2.69 (0.96, 7.56), p=0.060, respectively] and syphilis infection [AOR 1.86 (1.04, 3.31), p=0.036; AOR 3.35 (1.78, 6.28), p<0.001, respectively], but not with exposure to peer education, community mobilization or HIV testing uptake. Mediation analysis suggests that alcohol use and STIs may partially mediate the association between violence or arrests and HIV prevalence.

Discussion

Violence by non-partners and arrest are both strongly associated with HIV infection among FSWs. Large-scale, comprehensive HIV prevention programming can reduce violence, arrests and HIV/STI infection among FSWs.     

Value of eosinophil cationic protein and tryptase levels in bronchoalveolar lavage fluid for predicting lung function impairment in anaesthetised, asthmatic children

Bronchial hyperactivity, a key feature of active asthma in children, is a risk factor for respiratory adverse events in the peri-operative period. The presence of activated eosinophils in the lungs and mast cell degranulation can contribute to bronchial hyperreactivity. Eosinophil cationic protein is released by activated eosinophils and tryptase reflects mast cell degranulation. This study focused on the relationship of respiratory mechanics, eosinophil cationic protein and tryptase levels in bronchoalveolar lavage fluid in asthmatic and healthy children under general anaesthesia. We measured eosinophil cationic protein and tryptase levels in bronchoalveolar lavage fluid from 21 asthmatic and 21 healthy children following induction of general anaesthesia. Respiratory system resistance and dynamic compliance were measured during mechanical ventilation. Eosinophil cationic protein was more common in bronchoalveolar lavage fluid from asthmatics (12/21) than from controls (4/21, p = 0.01) and was present at higher levels (p = 0.002). Tryptase was also more common in the asthmatics (8/21 vs 1/21, p = 0.01). Respiratory resistance was significantly higher in asthmatic children with detectable eosinophil cationic protein levels than in those with undetectable eosinophil cationic protein levels (p = 0.019). Furthermore, 50% of the asthmatics with detectable eosinophil cationic protein exhibited bronchospasm after sampling their bronchoalveolar lavage fluid. These findings suggested that high levels of eosinophil cationic protein in the bronchoalveolar lavage fluid are associated with irritable airways, presumably secondary to airway inflammation, and this might be a useful marker for respiratory adverse events in the peri-operative period.     

Epithelioid Sarcoma of the External Auditory Canal: An Uncommon Tumor at an Unusual Site and a Brief Overview of the Literature

We present a case (41 years old pregnant female) with epithelioid sarcoma arising in the left external auditory canal. On immunohistochemistry, the tumor cell diffusely expressed cytokeratins and showed patchy expression of ERG and CD34. The neoplastic cells demonstrated uniform loss of INI1-expression. Epithelioid sarcoma arising in the external auditory canal is rare. Awareness that ES may rarely arise at unusual sites is of critical importance in order to apply a broad enough panel in the immunohistochemical study, so a misdiagnosis of carcinoma can be avoided.     

Outcomes following selective fetoscopic laser ablation for twin-to-twin transfusion syndrome: a single-centre experience

INTRODUCTIONFetoscopic laser photocoagulation (FLP), a treatment option for twin-to-twin transfusion syndrome (TTTS) in monochorionic twin pregnancies, is currently the treatment of choice at our centre. We previously reported on our experience of FLP from June 2011 to March 2014. This paper audits our fetal surgery performance since then.METHODS15 consecutive patients who underwent FLP for Stage II–III TTTS before 26 weeks of gestation from June 2011 to January 2017 were retrospectively reviewed, consisting of five cases from our initial experience and ten subsequent cases. Perioperative, perinatal and neonatal outcomes were analysed.RESULTSOf 15 pregnancies, 10 (66.7%) and 5 (33.3%) were for Stage II and III TTTS respectively, with FLP performed at an earlier Quintero stage in the later cohort. Overall mean gestational ages at presentation, laser and delivery were comparable between the cohorts at 19.7 (15.4–24.3) weeks, 20.3 (16.3–25.0) weeks and 31.2 (27.6–37.0) weeks, respectively. 2 (13.3%) cases had intra-amniotic bleeding and 1 (6.7%) had iatrogenic septostomy. 1 (6.7%) case had persistent TTTS requiring repeat FLP, and another (6.7%) had preterm premature rupture of membranes at seven weeks post procedure. The overall perinatal survival rate was 21 (75.0%) out of 28 infants. One mother underwent termination of pregnancy for social reasons at 1.4 weeks post procedure. Double survival occurred in 8 (57.1%) out of 14 pregnancies, while 13 (92.9%) had at least one survivor.CONCLUSIONFLP requires a highly specialised team and tertiary neonatal facility. Continual training improves maternal and perinatal outcomes, ensuring comparable standards with international centres.     

Bronchial and pulmonary arterial and venous interventions

With advancement of interventional techniques and increasing complexity of patients, the involvement of interventional radiologists in the pulmonary critical care (PCC) setting has increased in recent years. Particularly, interventional radiologists have evolved to play a significant role in treating patients with vascular pathologies such as massive pulmonary embolism. In this article, we discuss management of these critically ill patients using four pulmonary and bronchial vascular interventional procedures: bronchial artery embolization in the setting of hemoptysis; pulmonary artery embolization in the setting of the treatment of AVM; thrombectomy and thrombolysis of the pulmonary arteries for the treatment of pulmonary embolism; and catheter-directed stent placement in the treatment of superior vena cava syndrome.     

Strain and screening effects on field emission properties of armchair graphene nanoribbon arrays: a first-principles study

The field screening effect on the field-emission properties of armchair graphene nanoribbons (AGNRs) under strain has been studied using first-principles calculations with local density approximation (LDA). Using the zone folding method with the effect of a dipole barrier along with the work function of strained graphene, we can obtain the work function of AGNR of any width under strain, confirmed with the LDA calculations. We have systematically investigated the effects of inter-ribbon distance and ribbon width on the work function of AGNR arrays. It is found that the work function of AGNR arrays increases rapidly as the inter-ribbon distance D_x increases, which is caused by the positive dipole at the edge of the ribbon. Using a simple linear interpolation model, we can obtain the work function of AGNRs of any ribbon-width and inter-ribbon distance. The dependences of the inter-ribbon distance and strain on the field enhancement factor have been determined. The enhancement factor reaches about 90% of its saturated value as the inter-ribbon distance approaches two times the ribbon-width. For a tensile strain, the field enhancement factor increases with applied strain while for a compressive one, the field enhancement factor is nearly independent. The effects of inter-ribbon distance and strain on the enhancement factor can be explained by the interlayer and intralayer screening effects, respectively.

The field screening effect on the field-emission properties of armchair graphene nanoribbons (AGNRs) under strain has been studied using first-principles calculations with local density approximation (LDA).     

Individual Differences in Impulsive Action Reflect Variation in the Cortical Serotonin 5-HT2A Receptor System

Impulsivity is an important feature of multiple neuropsychiatric disorders, and individual variation in the degree of inherent impulsivity could play a role in the generation or exacerbation of problematic behaviors. Serotonin (5-HT) actions at the 5-HT_2AR receptor (5-HT_2AR) promote and 5-HT_2AR antagonists suppress impulsive action (the inability to withhold premature responses; motor impulsivity) upon systemic administration or microinfusion directly into the medial prefrontal cortex (mPFC), a node in the corticostriatal circuit that is thought to play a role in the regulation of impulsive action. We hypothesized that the functional capacity of the 5-HT_2AR, which is governed by its expression, localization, and protein/protein interactions (eg, postsynaptic density 95 (PSD95)), may drive the predisposition to inherent impulsive action. Stable high-impulsive (HI) and low-impulsive (LI) phenotypes were identified from an outbred rodent population with the 1-choice serial reaction time (1-CSRT) task. HI rats exhibited a greater head-twitch response following administration of the preferential 5-HT_2AR agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) and were more sensitive to the effects of the selective 5-HT_2AR antagonist M100907 to suppress impulsive action relative to LI rats. A positive correlation was observed between levels of premature responses and 5-HT_2AR binding density in frontal cortex ([³H]-ketanserin radioligand binding). Elevated mPFC 5-HT_2AR protein expression concomitant with augmented association of the 5-HT_2AR with PSD95 differentiated HI from LI rats. The observed differential sensitivity of HI and LI rats to 5-HT_2AR ligands and associated distinct 5-HT_2AR protein profiles provide evidence that spontaneously occurring individual differences in impulsive action reflect variation in the cortical 5-HT_2AR system.