Virtual reality simulation objectively differentiates level of carotid stent experience in experienced interventionalists

OBJECTIVES: Technical proficiency in carotid artery stent (CAS) procedures is paramount to ensure patient safety. If virtual reality (VR) simulation is to be used as a valid means for credentialing physicians for CAS procedures, the assessment parameters must be able to evaluate the performance during CAS and to differentiate level of CAS experience. The aim of this study was to validate assessment parameters of a commercially available VR simulator (VIST, Vascular Interventional Surgical Trainer, Mentice, Gothenburg, Sweden) during a CAS procedure in experienced interventionalists. METHODS: Forty-five interventionalists (cardiologists, radiologists, vascular surgeons) who had performed at least 100 endovascular therapeutic cases, with varying experience in CAS were recruited: groups A, n = 12 (0 CAS procedures), B, n = 12 (1 to 20 CAS), C, n = 10 (21 to 50 CAS) and D, n = 11 (>50 CAS). All subjects performed a standard CAS procedure with a type I arch and were assessed by quantitative (procedure time, amount of contrast given, number of cineloops recorded, fluoroscopic time) and qualitative (clinical parameters and errors) metrics of the simulator. Participants also rated the realism and training potential of the simulator on a scale from 1 (poor) to 5 (excellent). RESULTS: There were significant differences across the four groups A to D for procedure time (medians 20.5 vs 24 vs 19 vs 16 minutes, P = .002) and fluoroscopic time (12.5 vs 13 vs 10 vs 7 minutes, P < .001), respectively. Total numbers of errors recorded by the VR simulator did not achieve statistical significance (P = .209) across the four groups. All subjects rated the simulator highly (median 4) in terms of realism and training potential. CONCLUSIONS: Total time and fluoroscopic time both recorded by a realistic VR simulator differentiate between levels of CAS experience in experienced interventionalists. Error scoring is currently not a valid mode of assessment and needs refinement.     

Intracranial pressure observations in a canine model of acute liver failure supported by a bioartificial liver support system

Abstract:  Life-threatening, severely elevated intracranial pressure (ICP) is a common feature of acute liver failure (ALF). Perfusion with a bioartificial liver may serve to mitigate rising ICP. A retrospective analysis of ICP measurements in a canine ALF model prospectively supported with a bioartificial liver support system (BLSS) is presented. Animals are divided into two groups based upon care provided: (i) standard medical care ( n  = 6); and (ii) standard medical care plus BLSS support ( n  = 9). Nonparametric analysis with respect to ICP, arterial NH₃, lactate, and supportive-care parameters found BLSS-supported animals evidenced significantly less metabolic acidosis than unsupported animals. Analysis of variance/linear regression for direct dependence of ICP on arterial NH₃, lactate, and supportive care parameters irrespective of care found ICP was uncorrelated with any measured factor ( P  > 0.06 for all factors). Lack of correlation of ICP with the considered parameters indicates that none of these factors are predictive of the extent of ICP elevation in the d -galactosamine canine model. Blood chemistry and supportive care factors that are correlated with and predictive of ICP elevation remain to be identified.     

Endoscopic Cervical Bariatric Surgery: Follow-up Study in a Porcine Model

BACKGROUND: The realisation of bariatric surgery has to date modified the digestive process solely through procedures within the abdominal cavity. However, endocrine surgeons have recently demonstrated the feasibility of a minimally invasive approach to the neck. In this study, we explored the feasibility, safety and weight progression of a bariatric procedure performed at the neck. METHODS: Eleven 40-50 kg Yorkshire pigs underwent endoscopic placement of an adjustable band to the cervical esophagus (ECB). Weight was monitored at postoperative days 15, 30, and after 7 weeks; weight progression was compared with an identical group of pigs who underwent a sham procedure. At autopsy, the surgical site was evaluated in a microscopic and macroscopic manner. RESULTS: Mean operating time was 66 +/- 5.76 min. All pigs tolerated the procedure well, except one subject that experienced food intolerance. The ECB group experienced significantly slower weight gain than the sham group (P = 0.005). Proper location of the band and absence of microscopic lesions at the esophageal wall were confirmed at autopsy and pathological examination. CONCLUSION: Bariatric surgery at the neck is feasible and produces effects on weight reduction. Further refinements and longer observation periods are required to propose this procedure as safe and effective alternative in humans.     

Technique of anterior urethroplasty using the tunica albuginea of the corpora cavernosa

OBJECTIVE: To describe a technique of anterior urethroplasty using the tunica albuginea of the corpora cavernosa. METHODS: We performed this technique on 99 male patients with anterior urethral stricture with follow-up at 6, 12 and 18 months. We assessed preoperative and postoperative patient satisfaction rate based on symptoms along with preoperative and postoperative urethrograms, urethrosonographies and uroflowmetry and labelled outcomes as good, fair and poor. RESULTS: Good and fair results were considered successful. The overall success rate was 95.9%. In our series of patients, the overall success rate of urethroplasty remained the same at 6 months, but decreased to 94.9% at 12 months and 88.1% at 18 months. CONCLUSION: These observations show that anterior urethroplasty by using the tunica albuginea of the corpora cavernosa produced satisfactory results and is comparable with the other techniques of urethroplasty. The merits of using the tunica albuginea for urethroplasty are local availability of tissues, so that there is no need to use anatomically and structurally dissimilar distant tissue such as the buccal mucosa, preputial, penile, or scrotal skin or Teflon grafts. It can be used in our area where most of the patients come with dyskeratotic changes in their buccal mucosa.     

Thymoquinone inhibits tumor angiogenesis and tumor growth through suppressing AKT and extracellular signal-regulated kinase signaling pathways

Thymoquinone, a component derived from the medial plant Nigella sativa, has been used for medical purposes for more than 2,000 years. Recent studies reported that thymoquinone exhibited inhibitory effects on cell proliferation of many cancer cell lines and hormone-refractory prostate cancer by suppressing androgen receptor and E2F-1. Whether thymoquinone inhibits tumor angiogenesis, the critical step of tumor growth and metastasis, is still unknown. In this study, we found that thymoquinone effectively inhibited human umbilical vein endothelial cell migration, invasion, and tube formation. Thymoquinone inhibited cell proliferation and suppressed the activation of AKT and extracellular signal-regulated kinase. Thymoquinone blocked angiogenesis in vitro and in vivo, prevented tumor angiogenesis in a xenograft human prostate cancer (PC3) model in mouse, and inhibited human prostate tumor growth at low dosage with almost no chemotoxic side effects. Furthermore, we observed that endothelial cells were more sensitive to thymoquinone-induced cell apoptosis, cell proliferation, and migration inhibition compared with PC3 cancer cells. Thymoquinone inhibited vascular endothelial growth factor-induced extracellular signal-regulated kinase activation but showed no inhibitory effects on vascular endothelial growth factor receptor 2 activation. Overall, our results indicate that thymoquinone inhibits tumor angiogenesis and tumor growth and could be used as a potential drug candidate for cancer therapy.     

Giant ruptured sinus of Valsalva aneurysm: diagnosis on echocardiography

A giant ruptured sinus of Valsalva aneurysm was diagnosed ontransthoracic and subsequent transesophageal echocardiography,in a 45-year-old man who presented with gradual onset shortnessof breath. Although the initial presentation was insidious,he later rapidly deteriorated. We discuss the unusual clinicalcourse in a patient with such a large aneurysm and discuss thelikely reasons.     

Depressive symptoms and chronic obstructive pulmonary disease: effect on mortality, hospital readmission, symptom burden, functional status, and quality of life

BACKGROUND: Depressive symptoms are common among patients with chronic obstructive pulmonary disease (COPD), but depression's impact on COPD outcomes has not been fully investigated. We evaluated the impact of comorbid depression on mortality, hospital readmission, smoking behavior, respiratory symptom burden, and physical and social functioning in patients with COPD. METHODS: In this prospective cohort study, 376 consecutive patients with COPD hospitalized for acute exacerbation were followed up for 1 year. The independent associations of baseline comorbid depression (designated as a Hospital Anxiety and Depression Scale score of > or =8) with mortality, hospital readmission, length of stay, persistent smoking, and quality of life (determined by responses to the St George Respiratory Questionnaire) were evaluated after adjusting for potential confounders. RESULTS: The prevalence of depression at admission was 44.4%. The median follow-up duration was 369 days, during which 57 patients (15.2%) died, and 202 (53.7%) were readmitted at least once. Multivariate analyses showed that depression was significantly associated with mortality (hazard ratio, 1.93; 95% confidence interval, 1.04-3.58), longer index stay (mean, 1.1 more days; P = .02) and total stay (mean, 3.0 more days; P = .047), persistent smoking at 6 months (odds ratio, 2.30; 95% confidence interval, 1.17-4.52), and 12% to 37% worse symptoms, activities, and impact subscale scores and total score on the St George Respiratory Questionnaire at the index hospitalization and 1 year later, even after controlling for chronicity and severity of COPD, comorbidities, and behavioral, psychosocial, and socioeconomic variables. CONCLUSIONS: Comorbid depressive symptoms in patients with COPD are associated with poorer survival, longer hospitalization stay, persistent smoking, increased symptom burden, and poorer physical and social functioning. Interventions that reduce depressive symptoms may potentially affect COPD outcomes.