Ultrasound-guided vs. fluoro-guided axillary venous access for cardiac implantable electronic devices: a patient-based meta-analysis.

Aims: The use of ultrasound (US)-guided venous puncture for cardiac pacing/defibrillation lead placement may minimize the risk of periprocedural complications and radiation exposure. However, none of the published studies have been sufficiently powered to recommend this approach as the standard of care. We compare the safety and efficacy of ultrasound-guided axillary venous puncture (US-AVP) vs.

Does Rounding Order Bias Discharge Efficiency? Predictors of Discharge Timing on an Academic Urology Service.

No previous works have analyzed whether the order in which surgical teams see patients on morning rounds affects discharge efficiency at teaching hospitals. We obtained perioperative urologic surgery timing data at our academic institution from 2014 to 2019. We limited the analysis to routine postoperative day 1 discharges.

Intra-pocket ultrasound-guided axillary vein puncture vs. cephalic vein cutdown for cardiac electronic device implantation: the ACCESS trial.

Background And Aims: Intra-pocket ultrasound-guided axillary vein puncture (IPUS-AVP) for venous access in implantation of transvenous cardiac implantable electronic devices (CIED) is uncommon due to the lack of clinical evidence supporting this technique. This study investigated the efficacy and early complications of IPUS-AVP compared to the standard method using cephalic vein cutdown (CVC) for CIED implantation.

Methods: ACCESS was an investigator-led, interventional, randomized (1:1 ratio), monocentric, controlled superiority trial.

A Phenomenological Exploration of Experiences Related to Learning Styles Among Undergraduate Medical Students in a Barbadian Medical School.

Introduction: Learning style (LS) frameworks have been implemented by educators to promote participatory learning in order to strengthen learner engagement and to enhance learning outcomes. Self-efficacy has been shown to have an association with learning style and is a predictor of clinical performance and other qualities in medical students. This study examined the perspectives of second and final year medical students in a Caribbean-based medical school, relative to their learning approaches, teaching exposures and preparation for assessments.

Significant financial differences of chemical and surgical androgen deprivation in a contemporary cohort.

Background: Androgen deprivation therapy (ADT) remains a cornerstone of treatment for advanced prostate cancer. Few men elect for surgical castration via bilateral orchiectomy. We sought to compare the relative difference in financial charges between chemical and surgical ADT in men.

Assessment of HDR brachytherapy-replicating prostate radiotherapy planning for tomotherapy, cyberknife and VMAT.

A dosimetric study was undertaken to assess the ability of Cyberknife (CK), Volumetric Modulated Arc Therapy (VMAT), and TomoTherapy (Tomo) to generate treatment plans that mimic the dosimetry of high dose-rate brachytherapy (HDR BT) for prostate cancer. The project aimed to assess the potential of using stereotactic body radiotherapy (SBRT) for boost treatment of high-risk prostate cancer patients where HDR BT in combination with conformal external beam radiotherapy (EBRT) is the standard of care. The datasets of 6 prostate patients previously treated with HDR BT were collated.

Distributed feedback lasers using surface gratings in Bragg waveguides.

This Letter presents, to the best of our knowledge, the first report of a narrow-linewidth ∼790-800 edge-emitting semiconductor distributed feedback Bragg reflection waveguide diode laser (). The were fabricated using a ridge waveguide structure with 5th order, surface-etched grating forming the wavelength selective element. Unbonded devices with a 500 µm cavity length exhibited continuous wave threshold currents in the region of 25 mA with an output power of 2.

2020 family medicine postgraduate examinations at The University of the West Indies: successes and challenges in the time of COVID-19 pandemic.

Little has been published regarding postgraduate assessments during the COVID-19 pandemic. There is an urgent need to graduate well-trained specialists including family physicians who play a key role in patient care. The successes and challenges encountered in mounting qualifying 2020 Family Medicine examinations during the COVID-19 pandemic at the University of the West Indies are described in this paper.

Technical Note: Small field dose correction factors for radiochromic film in lung phantoms.

Purpose: Radiochromic film has been established as a detector that can be used without the need for perturbation correction factors for small field dosimetry in water. However, perturbation factors in low density media such as lung have yet to be published. This study calculated the factors required to account for the perturbation of radiochromic film when used for small field dosimetry in lung equivalent material.

Recommendations for simulating and measuring with biofabricated lung equivalent materials based on atomic composition analysis.

Monte Carlo simulations of lung equivalent materials often involve the density being artificially lowered rather than a true lung tissue (or equivalent plastic) and air composition being simulated. This study used atomic composition analysis to test the suitability of this method. Atomic composition analysis was also used to test the suitability of 3D printing PLA or ABS with air to simulate lung tissue.

Predicting the required thickness of custom shielding materials in kilovoltage radiotherapy beams.

The planning and delivery of kilovoltage (kV) radiotherapy treatments involves the use of custom shielding designed and fabricated for each patient. This study investigated methods by which the required thickness of custom shielding could be predicted for non-standard shielding materials fabricated using 3D printing techniques. Seven kV radiation beams from a WOmed T-300 X-ray therapy unit were modelled using SpekPy software, and AAPM TG-61 data were used to account for backscatter and spectral effects, for incrementally increasing thicknesses of Pb, W-PLA composite and Cu-PLA composite materials.

Association between the lengths of excised obstructed vas deferens segments at the time of vasovasostomy and surgical outcomes.

Objective: This study aimed to determine whether the length of the excised obstructed vas deferens at vasovasostomy (VV) performed for fertility is associated with semen parameters and/or pregnancy outcomes postoperatively.

Material And Methods: The patients who underwent a VV at our institution from September 2004 to December 2018 were contacted via questionnaire and a chart review was performed. Linear and logistic regression models were used to determine the associations between the length of the obstructed vas deferens removed and postoperative outcomes including sperm concentration, motility, and successful pregnancy after reversal.

Assessing the suitability of a two-dimensional array for routine quality assurance checks of flatness and symmetry.

Quality assurance of radiotherapy linear accelerator beams demands the use of equipment with high resolution and reliability of reproducible results over time. This study examines the suitability of a commercially available two-dimensional ionization chamber array-the StarCheck array (PTW, Frieburg, Germany) to measure symmetry and flatness for both photon and electron beams. The study was conducted over a period of 4 years whereby the reliability of the array could be established.

The effect of megavoltage field size on intrafraction cone-beam CT image quality.

To investigate the effects of scatter from a megavoltage treatment beam on intrafraction cone beam CT (CBCT) image quality. The effects of treatment beam field size and phantom geometry were investigated as well as the clinical success of IFI. Intrafraction imaging (IFI) was performed on four phantoms with four different MV field sizes using a 6 MV FFF source.

Treatment Setting Influences Treatment Modality for Urinary Stone Disease.

Objective: To determine whether selection of treatment modality for urinary stone disease differs between primary and outreach healthcare centers, and if patient rurality predicts treatment modality.

Methods: We retrospectively evaluated Extracorporeal shock wave lithotripsy (ESWL) and ureteroscopy (URS) procedural data from the Iowa Office of Statewide Clinical Education Programs (OSCEP) and Iowa Hospital Association (IHA) databases from 2007 to 2014. Geographical data was used to analyze travel metrics and patient proximity to sites of stone treatment.

Single-mode Bragg ring laser diodes.

We have designed and fabricated a monolithic semiconductor ring laser based on a Bragg waveguide structure. Through careful control of the waveguiding, we have overcome the inherent "leaky" nature of this waveguide mode and demonstrated a ring laser lasing in the Bragg mode. Best behavior was obtained from lasers with a diameter of 400 µm, where they exhibited output power ${ \gt }{1}\;{\rm mW}$>1mW, in continuous wave (CW) operation.

Melanin Produced by the Fast-Growing Marine Bacterium Vibrio natriegens through Heterologous Biosynthesis: Characterization and Application.

Melanin is a pigment produced by organisms throughout all domains of life. Due to its unique physicochemical properties, biocompatibility, and biostability, there has been an increasing interest in the use of melanin for broad applications. In the vast majority of studies, melanin has been either chemically synthesized or isolated from animals, which has restricted its use to small-scale applications.

Does peak expiratory flow measured sitting differ from that measured standing? A cross-over study in primary care in Barbados.

Background: Several authorities recommend measuring peak expiratory flow (PEF) standing. Limited evidence suggests that PEF obtained sitting is similar in magnitude but there are no studies in African populations.

Aim: To determine in adults aged 18-60 years if PEF measured sitting differs from that measured standing.

A High Aspect Ratio Bifurcated 128-Microchannel Microfluidic Device for Environmental Monitoring of Explosives.

Design and evolution of explosives monitoring and detection platforms to address the challenges of trace level chemical identification have led investigations into the use of intricately designed microfluidic devices. Microfluidic devices are unique tools that possess distinct characteristics that, when designed properly and configured with optical and fluidic components, can produce detection platforms with unmatched performance levels. Herein, we report the design, fabrication and integration of a bifurcated high aspect ratio microfluidic device containing 128 microchannels (40 mm × 40 μm × 250 μm; L × W × H) for explosives detection at trace levels.

Pilot Study to Determine Optimal Stent Duration Following Ureteroscopy: Three versus Seven days.

Background/aims: Many providers elect to place a stent following ureteroscopy for nephrolithiasis, but little data exists on the optimal duration to leave a stent. We sought to determine whether there are any differences in post-operative outcomes for patients with a 3 versus 7-day stent following ureteroscopy.

Methods: We retrospectively reviewed 247 patients who underwent unilateral ureteroscopy with lithotripsy, 79 of whom removed a stent with an extraction string at 3 or 7 days post-operatively.

A comparative study of three small-field detectors for patient specific stereotactic arc dosimetry.

This paper examines the difference in patient specific dosimetry using three different detectors of varying active volume, density and composition, for quality assurance of stereotactic treatments. A PTW 60017 unshielded electron diode, an Exradin W1 scintillator, and a PTW 31014 PinPoint small volume ionisation chamber were setup in a Lucy 3D QA phantom, and were positioned at the isocentre of an Elekta Axesse, with beam modulator collimator, using Exactrac and a HexaPODTM couch. Dose measurements were acquired for 43 stereotactic arcs, and compared to BrainLAB iPlan version 3.

Increasing the size of ureteral access sheath during retrograde intrarenal surgery improves surgical efficiency without increasing complications.

Purpose: To directly compare intraoperative and post-operative outcomes and complications between three groups undergoing ureteroscopy: no ureteral access sheath, 12/14 Fr and larger 14/16 Fr ureteral access sheaths (UAS).

Methods: We retrospectively reviewed demographic, pre-operative, intraoperative, and post-operative data of 257 patients who underwent ureteroscopy for nephrolithiasis by a single surgeon from January 2013 through July 2015. Patients were separated into three groups: no UAS, a 12/14 Fr UAS, or 14/16 Fr UAS.

Feasibility of 3D printed air slab diode caps for small field dosimetry.

Commercial diode detectors used for small field dosimetry introduce a field-size-dependent over-response relative to an ideal, water-equivalent dosimeter due to high density components in the body of the detector. An air gap above the detector introduces a field-size-dependent under-response, and can be used to offset the field-size-dependent detector over-response. Other groups have reported experimental validation of caps containing air gaps for use with several types of diodes in small fields.