785 Ankle Fractures Management in Stoke Mandeville Hospital

Introduction

Ankle fractures treatment aims to restore joint stability and alignment to achieve full functional recovery. Current quality of care in Stoke Mandeville Hospital was compared to the gold-standard management approach as described in BOAST-12 guidelines.

Method

This closed loop audit looked at closed malleolar and syndesmotic ankle injuries in skeletally mature patients under Trauma and Orthopaedics. In the first audit cycle, 16 patients were included over a one-month period and 53 cases, with similar management, were identified over a three-month period for the second audit cycle.

Results

The initial audit cycle revealed that the main aspects of management that required improvement were the timing of reduction and splinting, as well as the documentation of neurovascular status post-reduction.

We discussed our findings at the clinical governance meeting and interventional posters were distributed around the hospital.

Documentation of the timing of reduction and splinting significantly increased from 6% to 85% post-interventions, and neurovascular examination post-reduction improved from 17% to 43%. All other quality assessment criteria recorded more than 90% documentation rates after implementation of changes.

Conclusions

Quality of care significantly improved post-interventions, which indicates that BOAST-12 gold-standard is achievable. The introduction of a proforma was suggested to further facilitate appropriate documentation.

QRS dispersion using 252-leads Body Surface Mapping (BSM) – an explorative study of a novel diagnostic tool for Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

Background

The diagnosis of ARVC is complex and challenging requiring multiple investigational tools, most of which include the demonstration of depolarization/conduction abnormalities, described in recent HRS consensus documents 2019. A simple and user friendly diagnostic tool is warranted.

Purpose

The purpose of our study was therefore to explore whether the analysis of QRS dispersion obtained from 252-leads recorded by a Body Surface Mapping (BSM) system can be used to identify ARVC patients as compared to the traditional ECG criteria including QRS dispersion measured by conventional 12 lead surface ECG.

Methods

12 definite ARVC patients (10/12 with known pathogenic mutation) (Group 1) and 8 healthy family members tested negative for the family mutation served as controls (Group 0), were included. All patients underwent 12-lead ECG (50mm/sec), Signal-averaged ECG for late potentials and 252 lead BSM recordings. The QRS duration was measured in each of the 12 ECG leads manually with digital caliper. The QRS duration from the BSM leads were manually analyzed in Matlab by two observers unaware of the diagnosis. For each lead, the mean value of three randomly chosen beats was calculated. The QRS dispersion was calculated as the difference between the minimum and maximum value for both the 12 lead ECG and the BSM recordings.

Results

The mean age was 49,6 and 38,8 years in ARVC patients and controls, respectively. The number of males in the two groups were 8/12 and 5/8, respectively. Epsilon waves and Terminal Activation Duration (TAD) >55msec were detected in 6/12 and 8/12 ARVC patients, respectively, but in no controls. Late potentials were detected in 11/12 ARVC patients and in 2 controls. The QRS duration and QTc duration was not statistically different in the two Groups.

The ECG-QRS dispersion was significantly more pronounced in Group 1 (42 ms ± 15, range 20–70 ms) than in Group 0 (26 ms ± 8, range 16–36 ms) (p=0.013). The BSM-QRS dispersion was significantly longer in Group 1 (68 ms ± 17, range 29–90ms) than in Group 0 (30 ms ± 7, range 22–41ms) (p=0.001). Only one ARVC patient had a BSM-QRS dispersion <50 msec, whereas none of the controls had a QRS dispersion over 50 msec (Fig. 1).

Conclusion

BSM-QRS dispersion, specifically using the cut off <50 ms, can potentially be a more sensitive and specific method than other ECG related techniques for diagnosing ARVC patients versus non-ARVC patients. Larger patient cohorts and further studies are required to confirm our findings.

Figure 1. ECG and BSM-QRS dispersion

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Selanders Stiftelse

The repolarization pattern of ARVC patients, healthy gene carriers and controls as analyzed with a 252-leads Body Surface Mapping Vest

Background

Repolarization abnormalities have a central role on the diagnosis of ARVC according to recent HRS consensus document from 2019 stating that T wave inversion in the right precordial leads is a major criteria if it appears in V1-V3 or a minor criteria if it appears in only V1-V2.

Purpose

The aim of our study was to investigate whether repolarization patterns as recorded by a Body Surface Mapping (BSM) system consisting of a vest with 252 ECG leads, could differentiate ARVC patients and even gene carriers from normal individuals. Our hypothesis is that the method can potentially identify repolarization disturbances earlier or better than conventional 12-lead ECG.

Method

12 definite ARVC patients, 20 healthy gene carriers and 8 family members who tested negative for the family mutation (controls) were included. All patients underwent 12-lead ECG, including right precordial leads (V4R) and BSM recordings. Repolarization (T-wave polarity and concordance with QRS complex vector) was analyzed qualitatively in all BSM recordings, the results of which were displayed on a color code map (fig.1).

Results

The mean age was 49.6, 43.6 and 38.8 years in ARVC patients, healthy gene carriers and controls, respectively. The number of males in the three groups were 8/12, 8/20 and 5/8, respectively.

All 8 controls had similar repolarization patterns with negative and concordant T waves on the right back panel, and T waves that successively changed from negative concordant (green) to positive disconcordant (red) and finally positive concordant (blue) on the left front panel (pattern 1). All 12 ARVC patients had different repolarization patterns as compared to the controls. Two of these patients had no apparent repolarization changes on conventional 12 lead ECG. The pattern type 2 repolarization, as defined by same pattern as the controls at the right back panel but different pattern at the front left panel was seen in 3/12 ARVC patients. The remaining 9 ARVC patients had different repolarization patterns both on the front and on the back panel (pattern 3). Among gene carriers, 15 had a normal repolarization pattern (pattern 1) and 5 demonstrated an abnormal repolarization pattern (4 had pattern type 2 and one pattern 3) despite normal surface ECG.

Conclusions

Using BSM recordings, abnormal repolarization patterns can be detected in all ARVC patients, even in those without repolarization changes on conventional surface ECG. The observation that 25% of gene carriers had divergent repolarization patterns, may indicate an early stage of the disease, and be used as an early diagnostic marker of the disease. Further and larger studies are warranted to confirm these observations.

Repolarisation patterns recorded by BSM

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Selanders Stiftelse

Dense Deposit Disease Involving C3 and C4d Deposits

Dense deposit disease (DDD), earlier called Type II membranoproliferative glomerulonephritis is distinct disease having frequent relapses reaching end-stage kidney disease by 10-year in up to 50%-60% of cases and high recurrence rate in the allograft. The term DDD is derived from its distinctive ribbon-like osmiophilic deposits in the lamina densa of glomerular basement membrane by electron microscopy. Pathogenetically, alternate pathway dysfunction leads to this disease, which is diagnosed by ultrastructure. Herein, we describe our observation of C4d positivity in an adolescent boy with DDD.

Millimeter wave silicon micromachined waveguide probe as an aid for skin diagnosis--results of measurements on phantom material with varied water content

BACKGROUND

More than 2 million cases of skin cancer are diagnosed annually in the United States, which makes it the most common form of cancer in that country. Early detection of cancer usually results in less extensive treatment and better outcome for the patient. Millimeter wave silicon micromachined waveguide probe is foreseen as an aid for skin diagnosis, which is currently based on visual inspection followed by biopsy, in cases where the macroscopical picture raises suspicion of malignancy.

AIMS

Demonstration of the discrimination potential of tissues of different water content using a novel micromachined silicon waveguide probe. Secondarily, the silicon probe miniaturization till an inspection area of 600 × 200 μm2, representing a drastic reduction by 96.3% of the probing area, in comparison with a conventional WR-10 waveguide. The high planar resolution is required for histology and early-state skin-cancer detection.

MATERIAL AND METHODS

To evaluate the probe three phantoms with different water contents, i.e. 50%, 75% and 95%, mimicking dielectric properties of human skin were characterized in the frequency range of 95-105 GHz. The complex permittivity values of the skin are obtained from the variation in frequency and amplitude of the reflection coefficient (S11), measured with a Vector Network Analyzer (VNA), by comparison with finite elements simulations of the measurement set-up, using the commercially available software, HFSS. The expected frequency variation is calculated with HFSS and is based on extrapolated complex permittivities, using one relaxation Debye model from permittivity measurements obtained using the Agilent probe.

RESULTS

Millimeter wave reflection measurements were performed using the probe in the frequency range of 95-105 GHz with three phantoms materials and air. Intermediate measurement results are in good agreement with HFSS simulations, based on the extrapolated complex permittivity. The resonance frequency lowers, from the idle situation when it is probing air, respectively by 0.7, 1.2 and 4.26 GHz when a phantom material of 50%, 75% and 95% water content is measured.

DISCUSSION

The results of the measurements in our laboratory set-up with three different phantoms indicate that the probe may be able to discriminate between normal and pathological skin tissue, improving the spatial resolution in histology and on skin measurements, due to the highly reduced area of probing.

CONCLUSION

The probe has the potential to discriminate between normal and pathological skin tissue. Further, improved information, compared to the optical histological inspection can be obtained, i.e. the complex permittivity characterization is obtained with a high resolution, due to the highly reduced measurement area of the probe tip.

Aztreonam for injection (lyophilized): development of an automated solution batching process utilizing volumetric powder feeders

As part of a commitment to fully automate the manufacture of a lyophilized dosage form of Azactam (Aztreonam for Injection), an automated solution batching procedure was developed. The lyophilization process requires solution batching of Aztreonam and L-arginine, the two constituents of the product. To avoid preblending of aztreonam and L-arginine prior to dissolution, a batching process was developed which makes use of two separate volumetric powder feeders. In conjunction with a feedback pH control system, these powder feeders provided for (a) a faster batching process, (b) a tight control of solution pH during batching, (c) a failsafe system to prevent operator error and equipment malfunction. Data are presented correlating bulk densities of various powders with feeder output along with solution pH profiles determined using the manual mode and the automated feedback pH control system.

Calcium-dependent phosphorylation of histone H3 in butyrate-treated HeLa cells

Ca2+ is prominant in the control of cell proliferation and function. However, the biochemical mechanism(s) mediating its effects on nuclear events is unknown. We report here that Ca2+, at physiological concentrations, stimulates the phosphorylation of histone H3 by an endogenous protein kinase in HeLa cell nuclei. Also, pretreatment of cells with Na butyrate, which increases histone acetylation, selectively increases the susceptability of histone H3 to phosphorylation by the protein kinase. Our results reveal a potential link between histone H3 acetylation and phosphorylation, modifications which are thought to have important effects on chromatin structure and function and suggest a possible mechanism whereby stimuli at the cell surface (such as hormones, mitogens and drugs) may influence biochemical events at the nuclear level; changes in the intracellular Ca2+ concentration may influence the phosphorylation of chromosomal proteins, mediated by Ca2+ -dependent kinases in th nucleus.