Intraoperative angiography via the popliteal artery: a useful technique for patients in the prone position

OBJECTIVE Intraoperative angiography can be a valuable tool in the surgical management of vascular disorders in the CNS. This is typically accomplished via femoral artery puncture; however, this can be technically difficult in patients in the prone position. The authors describe the feasibility of intraoperative angiography via the popliteal artery in the prone patient. METHODS Three patients underwent intraoperative spinal angiography in the prone position via vascular access through the popliteal artery. Standard angiography techniques were used, along with ultrasound and a micropuncture needle for initial vascular access. Two patients underwent intraoperative angiography to confirm the obliteration of dural arteriovenous fistulas. The third patient required unexpected intraoperative angiography when a tumor was concerning for a vascular malformation in the cervical spine. RESULTS All 3 patients tolerated the procedure without complication. The popliteal artery was easily accessed without any adaptation to typical patient positioning for these prone-position cases. This proved particularly beneficial when angiography was not part of the preoperative plan. CONCLUSIONS Intraoperative angiography via the popliteal artery is feasible and well tolerated. It presents significant benefit when obtaining imaging studies in patients in a prone position, with the added benefit of easy access, familiar anatomy, and low concern for catheter thrombosis or kinking

The rate of hypo-osmotic challenge influences regulatory volume decrease (RVD) and mechanical properties of articular chondrocytes

Zhao Wang is funded on a China Scholarships PhD Studentship. Jerome Irianto was supported on a project grant from The Wellcome Trust (ref no. 084717)

Recent advances in experimental testing and computational modelling for characterisation of mechanical properties of biomaterials and biological cells

Biomaterials and biological cells possess a number of different properties; amongst them, mechanical properties are extremely important in studies and applications about tissue engineering, design and development of implants, surgical tools and medical devices for treatments and diagnosis of diseases. Changes in mechanical properties such as a stiffness of cells are often the signs of changes in cell physiology or diseases in tissues; and studying these changes can lead to the development of devices for early disease detection and new drug delivery mechanisms. This paper presents advances in recent years in experimental testing and computational modelling for characterisation of mechanical properties of biomaterials and biological cells, in which the presented research projects and related studies were mainly implemented by research groups in the UK. The recent important findings as well as research directions and challenges are emphasised and discussed, to open channels for research collaborations in development of cost-effective medical diagnosis and treatment solutions

The Open Source GAITOR Suite for Rodent Gait Analysis

Locomotive changes are often associated with disease or injury, and these changes can be quantified through gait analysis. Gait analysis has been applied to preclinical studies, providing quantitative behavioural assessment with a reasonable clinical analogue. However, available gait analysis technology for small animals is somewhat limited. Furthermore, technological and analytical challenges can limit the effectiveness of preclinical gait analysis. The Gait Analysis Instrumentation and Technology Optimized for Rodents (GAITOR) Suite is designed to increase the accessibility of preclinical gait analysis to researchers, facilitating hardware and software customization for broad applications. Here, the GAITOR Suite’s utility is demonstrated in 4 models: a monoiodoacetate (MIA) injection model of joint pain, a sciatic nerve injury model, an elbow joint contracture model, and a spinal cord injury model. The GAITOR Suite identified unique compensatory gait patterns in each model, demonstrating the software’s utility for detecting gait changes in rodent models of highly disparate injuries and diseases. Robust gait analysis may improve preclinical model selection, disease sequelae assessment, and evaluation of potential therapeutics

Disparities and guideline adherence in drugs of abuse screening in intracerebral hemorrhage

OBJECTIVE: To characterize the pattern of urine drug screening in a cohort of intracerebral hemorrhage (ICH) patients at our academic centers. METHODS: We identified cases of primary ICH occurring from 2009 to 2011 in our academic centers. Demographic data, imaging characteristics, processes of care, and short-term outcomes were ascertained. We performed logistic regression to identify predictors for screening and evaluated preguideline and postguideline reiteration screening patterns. RESULTS: We identified 610 patients with primary ICH in 2009-2011; 379 (62.1%) were initially evaluated at an outside hospital. Overall, 142/610 (23.3%) patients were screened, with 21 positive for cocaine and 3 for amphetamine. Of patients <55 years of age, only 65/140 (46.4%) were screened. Black patients <55 years of age were screened more than nonblack patients <55 years of age (38/61 [62.3%] vs 27/79 [34.2%]; p = 0.0009). In the best multivariable model, age group (p = 0.0001), black race (p = 0.4529), first Glasgow Coma Scale score (p = 0.0492), current smoking (p < 0.0001), and age group × black race (p = 0.0097) were associated with screening. Guideline reiteration in 2010 did not improve the proportion <55 years of age who were screened: 42/74 (56.8%) were screened before and 23/66 (34.9%) after (p = 0.01). CONCLUSIONS: We found disparities in drugs of abuse (DOA) screening and suboptimal guideline adherence. Systematic efforts to improve screening for DOA are warranted. Improved identification of sympathomimetic exposure may improve etiologic classification and influence decision-making and prognosis counseling

Cooperative learning in the first year of undergraduate medical education

<p>Abstract</p> <p>Background</p> <p>Despite extensive research data indicating that cooperative learning promotes higher achievement, the creation of positive relationships, and greater psychological health for students at all levels in their education, cooperative learning as a teaching strategy is still underutilized in undergraduate medical education.</p> <p>Methods</p> <p>A cooperative learning task was introduced as part of the mandatory first Year undergraduate Pathology course. The task was to create an 8.5" × 11" poster summary of pre-assigned content in self-chosen groups of four or five students. On the designated "Poster Day," the posters were displayed and evaluated by the students using a group product evaluation. Students also completed an individual group process reflection survey. An objective evaluation of their understanding was gauged at the midterm examination by specific content-related questions.</p> <p>Results</p> <p>Majority (91–96%) of students judged the group products to be relevant, effective, easy-to-understand, and clearly communicated. The majority of the students (90–100%) agreed that their group process skills of time management, task collaboration, decision-making and task execution were effective in completing this exercise. This activity created a dynamic learning environment as was reflected in the students' positive, professional discussion, and evaluation of their posters. The content-related questions on the midterm examination were answered correctly by 70–92% of the students. This was a mutually enriching experience for the instructor and students.</p> <p>Conclusion</p> <p>These findings demonstrate that cooperative learning as a teaching strategy can be effectively incorporated to address both content <it>and </it>interpersonal skill development in the early years of undergraduate medical education.</p

Ectopic internal carotid artery presenting as an oropharyngeal mass

Ectopic internal carotid artery (ICA) is a very rare variation. The major congenital abnormalities of the ICA can be classified as agenesis, aplasia and hypoplasia, and they can be unilateral or bilateral. Anomalies of the neck artery may be vascular neoplasms or ectopic position. Carotid angiograms provide absolute confirmation of an aberrant carotid artery, while EcoColorDoppler (ECD) gives also important information about the evaluation of carotid vassels. Nevertheless Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) of the neck provide spatial information about the adjacent pharyngeal anatomy and are less invasive than angiogram. Injuries to the ICA during simple pharyngeal surgical procedures can be catastrophic due to the risk of massive bleeding. We report a case of a 56 year-old male patient suffering from dysphagia associated with aberrant ICA manifesting itself as a pulsative protruding of the left lateral wall of the oropharynx

Prevalence and predictors of falls and dizziness in people younger and older than 80 years of age-A longitudinal cohort study.

The objectives were to investigate the prevalence and predictors for falls and dizziness among people younger and older than 80 years of age. The sample was drawn from the Swedish National study on Aging and Care (SNAC) and comprised 973 and 1273 subjects with data on the occurrence of falls and dizziness respectively at baseline. Follow-ups were made after 3- and 6-years. Data included socio-demographics, physical function, health complaints, cognition, quality of life and medications. The prevalence of falls was 16.5% in those under aged 80 and 31.7% in those 80+ years while dizziness was reported by 17.8% and 31.0% respectively. Predictors for falls in those under aged 80 were neuroleptics, dependency in personal activities of daily living (PADL), a history of falling, vision impairment and higher age, and in those 80+ years a history of falling, dependency in instrumental activities of daily living (IADL), fatigue and higher age. Factors predicting dizziness in those under aged 80 were a history of dizziness, feeling nervous and reduced grip strength and in those 80+ years a history of dizziness and of falling. Predictors for falls and dizziness differed according to age. Specific factors were identified in those under aged 80. In those 80+ years more general factors were identified implying the need for a comprehensive investigation to prevent falls. This longitudinal study also showed that falling and dizziness in many older people are persistent and therefore should be treated as chronic conditions

Anesthesiologists' and surgeons' perceptions about routine pre-operative testing in low risk patients: application of the Theoretical Domains Framework to identify factors that influence physicians' decisions to order pre-operative tests

Background Routine pre-operative tests for anesthesia management are often ordered by both anesthesiologists and surgeons for healthy patients undergoing low-risk surgery. The Theoretical Domains Framework (TDF) was developed to investigate determinants of behaviour and identify potential behaviour change interventions. In this study, the TDF is used to explore anaesthesiologists’ and surgeons’ perceptions of ordering routine tests for healthy patients undergoing low-risk surgery. Conclusion We identified key factors that anesthesiologists and surgeons believe influence whether they order pre-operative tests routinely for anesthesia management for a healthy adults undergoing low-risk surgery. These beliefs identify potential individual, team, and organisation targets for behaviour change interventions to reduce unnecessary routine test ordering. Methods Sixteen clinicians (eleven anesthesiologists and five surgeons) throughout Ontario were recruited. An interview guide based on the TDF was developed to identify beliefs about preoperative testing practices. Content analysis of physicians’ statements into the relevant theoretical domains was performed. Specific beliefs were identified by grouping similar utterances of the interview participants. Relevant domains were identified by noting the frequencies of the beliefs reported, presence of conflicting beliefs, and perceived influence on the performance of the behaviour under investigation. Results Seven of the twelve domains were identified as likely relevant to changing clinicians’ behaviour about pre-operative test ordering for anesthesia management. Key beliefs were identified within these domains including: conflicting comments about who was responsible for the test-ordering (Social/professional role and identity); inability to cancel tests ordered by fellow physicians (Beliefs about capabilities and social influences); and the problem with tests being completed before the anesthesiologists see the patient (Beliefs about capabilities and Environmental context and resources). Often, tests were ordered by an anesthesiologist based on who may be the attending anesthesiologist on the day of surgery while surgeons ordered tests they thought anesthesiologists may need (Social influences). There were also conflicting comments about the potential consequences associated with reducing testing, from negative (delay or cancel patients’ surgeries), to indifference (little or no change in patient outcomes), to positive (save money, avoid unnecessary investigations) (Beliefs about consequences). Further, while most agreed that they are motivated to reduce ordering unnecessary tests (Motivation and goals), there was still a report of a gap between their motivation and practice (Behavioural regulation)

Assessing the Permeability of Engineered Capillary Networks in a 3D Culture

Many pathologies are characterized by poor blood vessel growth and reduced nutrient delivery to the surrounding tissue, introducing a need for tissue engineered blood vessels. Our lab has developed a 3D co-culture method to grow interconnected networks of pericyte-invested capillaries, which can anastamose with host vasculature following implantation to restore blood flow to ischemic tissues. However, if the engineered vessels contain endothelial cells (ECs) that are misaligned or contain wide junctional gaps, they may function improperly and behave more like the pathologic vessels that nourish tumors. The purpose of this study was to test the resistance to permeability of these networks in vitro, grown with different stromal cell types, as a metric of vessel functionality. A fluorescent dextran tracer was used to visualize transport across the endothelium and the pixel intensity was quantified using a customized MATLAB algorithm. In fibroblast-EC co-cultures, the dextran tracer easily penetrated through the vessel wall and permeability was high through the first 5 days of culture, indicative of vessel immaturity. Beyond day 5, dextran accumulated at the periphery of the vessel, with very little transported across the endothelium. Quantitatively, permeability dropped from initial levels of 61% to 39% after 7 days, and to 7% after 2 weeks. When ECs were co-cultured with bone marrow-derived mesenchymal stem cells (MSCs) or adipose-derived stem cells (AdSCs), much tighter control of permeability was achieved. Relative to the EC-fibroblast co-cultures, permeabilities were reduced 41% for the EC-MSC co-cultures and 50% for the EC-AdSC co-cultures after 3 days of culture. By day 14, these permeabilities decreased by 68% and 77% over the EC-fibroblast cultures. Co-cultures containing stem cells exhibit elevated VE-cadherin levels and more prominent EC-EC junctional complexes when compared to cultures containing fibroblasts. These data suggest the stromal cell identity influences the functionality and physiologic relevance of engineered capillary networks