The impact of flash glucose monitoring on adults with type 1 Diabetes' eating habits and relationship with food

AIM

To gain a better understanding of how the FreeStyle Libre (FSL) flash glucose monitor influences the eating habits and relationship with food of adults with type 1 diabetes (T1D).

METHODS

Reflexive thematic analysis was conducted on fifteen semi-structured interviews conducted with adults with T1D, exploring their experiences of at least one year of FSL use.

RESULTS

Four themes were constructed from the qualitative data: (1) Personal Food Story (what food represented before and after diabetes diagnosis), (2) New Opportunities (the FSL offered novel discoveries and increased self-confidence regarding food choices), (3) Body as a Machine (participants viewed their bodies as a collection of complex processes requiring continuous maintenance), and (4) re-evaluating Diabetes (participants expressed a shift in their expectations of themselves and their diabetes management). Although the FSL offered participants more freedom and flexibility with their eating, this was constrained by feeling forever under scrutiny from the data.

CONCLUSIONS

Findings suggest the FSL influences users' eating habits, including when, why, what and how much they eat. Participants described both the positive and negative impact of these changes on their emotional wellbeing and relationship with diabetes, arguing for a need to address patients' relationship with food in routine clinic care.

FT-IR spectroscopy analysis of HF-treated mineral soils, a direct approach for deciphering organo-mineral interactions

Soil organic matter (SOM) constitutes roughly 60% organic carbon (OC) and therefore plays a crucial role in regulating global climate. However, our understanding of the long-term dynamics of the soil carbon pool remains constrained by limitations in analytical approaches capable of providing high resolution molecular-level information from arguably the most complex biomaterial on the planet. In this contribution, we combine hydrofluoric acid (HF) treatment with a spectroscopic approach as a strategy to provide refined molecular-level information on the interactions between soil minerals and SOM. Critically, we have not seen the use of this combined approach anywhere in the literature and strongly believe that it could allow us to improve our overall understanding to the mechanisms and pathways that regulate SOM transformation. Results clearly illustrates which organic structures are preferentially adsorbed to soil minerals and are likely to be protected from degradation, as well as spatial co-variations of SOM with specific mineral components such as Al³⁺, Si⁴⁺ and dibasic cations such as Mg²⁺as a function of their importance in the interaction process.•Soil samples were collected from different land-use types in rural farming communities of the Upper Rio Grande Valley.•Samples were oven dried, disaggregated, sieved, treated with 10% HF, rinsed and oven dried.•Oven dried samples were subjected to Mid-infrared (4000-400 cm^-1), XRD and ED-XRF analyses.

Identifying the research priorities of healthcare professionals in UK vascular surgery: modified Delphi approach

Background

The Vascular Research Collaborative was established to develop a national research strategy for patients with vascular disease in the UK. This project aimed to establish national research priorities in this patient group.

Methods

A modified Delphi approach, an established method for reaching a consensus opinion among a group of experts in a particular field, was used to survey national multidisciplinary vascular clinical specialists. Two rounds of online surveys were conducted involving the membership of the Vascular Society, Society of Vascular Nurses, Society for Vascular Technology, and the Rouleaux Club (vascular surgical trainees). The first round invited any suggestions for vascular research topics. A steering group then collated and rationalized the suggestions, categorizing them by consensus into pathological topics and research categories, and amalgamating the various questions relating to the same fundamental issue into a single question. The second round involved recirculating these questions to the same participants for priority scoring.

Results

Round 1 resulted in 1231 suggested research questions from 481 respondents. Steering group collation and rationalization resulted in 83 questions for ranking in round 2. The second round resulted in a hierarchical list of vascular research priorities. The highest scoring priorities addressed topics related to critical lower-limb ischaemia, diabetic foot disease, amputation, wound healing, carotid plaque morphology, and service organization/delivery.

Conclusion

It is anticipated that these results will drive the UK national vascular research agenda for the next 5–10 years. It will facilitate focused development and funding of new research projects in current clinical areas of unmet need where potential impact is greatest.

Compliance with NICE guidelines when commissioning varicose vein procedures

Background

Varicose veins impair quality of life and can lead to chronic leg ulcers. National Institute for Health and Care Excellence (NICE) guidelines (CG168) set out evidence-based standards for patient management. In England, Clinical Commissioning Groups (CCGs) fund NHS care within their locality. The objective of this study was to evaluate CCGs' commissioning policies and compare them with CG168.

Methods

Searches were made for the published policies of all 206 English CCGs. They were reviewed for compliance with NICE guidelines and the associated quality standard. Areas of disagreement were analysed for themes.

Results

Some 203 CCGs (98·5 per cent) had a published policy and 190 (93·6 per cent) of these were published after publication of CG168. Only 73 of the policies (36·0 per cent) were compliant with CG168. Treatment was restricted on the basis of clinical disease severity in 119 CCGs (58·6 per cent); 29 (14·3 per cent) stipulated delay of treatment using a 'trial' of conservative treatment; 22 (10·8 per cent) used lifestyle-related factors such as BMI and smoking status to ration treatment. Treatment was commissioned for uncomplicated symptomatic varicose veins in 87 CCGs (42·9 per cent), but some applied additional rationing mechanisms; 109 CCGs (53·7 per cent) would treat oedema, 183 (90·1 per cent) would treat skin and soft tissue damage, 202 (99·5 per cent) healed ulceration, and all would allow active ulcers to be treated.

Discussion

The majority of CCGs in England have commissioning policies that contradict NICE guidelines. Rationing strategies include disease severity, delay and patient lifestyle-related factors, creating unwarranted geographical variation for varicose vein treatment, disregarding the NHS Constitution for England, and perhaps leading to an increase in costly treatment of chronic complications in the long term.

Long-term outcomes of endovenous laser ablation and conventional surgery for great saphenous varicose veins

BACKGROUND

Clinical guidelines recommend endovenous laser ablation (EVLA) over surgery based on short-term evidence, yet there are few studies reporting mid- to long-term outcomes. The aim of this study was to report the 5-year outcomes from an RCT of surgery versus EVLA for treatment of symptomatic great saphenous varicose veins.

METHODS

Patients with symptomatic varicose veins due to great saphenous vein (GSV) incompetence were followed up 5 years after enrolment in a randomized trial of either surgery (saphenofemoral junction ligation, GSV strip to the knee and multiple avulsions of varicosities) or EVLA plus multiple avulsions. Outcomes included: clinical recurrence, defined as new varicose veins greater than 3 mm in diameter; Venous Clinical Severity Score (VCSS); quality of life measured by means of Short Form 36, EuroQol Five Dimensions (EQ-5D™) and Aberdeen Varicose Vein Questionnaire (AVVQ); patient satisfaction; and duplex ultrasound examination (DUS) findings.

RESULTS

Some 218 of the 276 patients enrolled in the trial (79·0 per cent) were available for follow-up. Clinical recurrence was more frequent following surgery than EVLA at 5 years (34·3 versus 20·9 per cent; P = 0·010). Both groups demonstrated sustained significant improvements at 5 years over baseline in VCSS (surgery: median (i.q.r.) 1 (0-2) from 4 (3-5), P < 0·001; EVLA: 0 (0-1) from 4 (3-5), P < 0·001), AVVQ (surgery: 4·59 (0·56-9·78) from 13·69 (9·81-18·11), P < 0·001; EVLA: 3·35 (0·17 to 6·55) from 12·73 (9·41-17·32), P < 0·001) and EQ-5D™ (surgery: 1·000 (0·796-1·000) from 0·859 (0·796-1·000), P = 0·002; EVLA: 1·000 (0·796-1·000) from 0·808 (0·796-1·000), P = 0·002). VCSS was better for EVLA than surgery at 5 years (P = 0·031). Technical success assessed by DUS remained high at 5 years (85·4 per cent for surgery and 93·2 per cent for EVLA; P = 0·074). DUS-detected anatomical patterns of recurrence differed between the groups.

CONCLUSION

EVLA was more effective than surgery in preventing clinical recurrence 5 years after treatment of great saphenous varicose veins. Patient-reported outcome measures were similar. Registration number: NCT00759434 (http://www.clinicaltrials.gov).

A retrospective cohort study: do patients with graves' disease need to be euthyroid prior to surgery?

Background

The 2016 American Thyroid Association guidelines indicate that patients with Graves’ disease who undergo a thyroidectomy should be rendered euthyroid through the use of antithyroid drugs (ATD) prior to surgery to avoid complications such as a thyroid storm. At times, the use of ATDs can have limited efficacy and therefore some patients will inevitably remain biochemically hyperthyroid at the time of surgery.

The aim of this study is to assess if hyperthyroid patients undergoing a thyroidectomy are at an increased risk of developing a thyroid storm in comparison to euthyroid patients. Furthermore, this study seeks to establish a correlation between thyroid storm identified by the levels of thyroid hormones (T3 and T4) and the level of thyroid stimulating hormone (TSH).

Methods

A retrospective cohort study was conducted at two Canadian centers, one in Montreal and the other in Nova Scotia. Sixty-seven patients undergoing thyroidectomy for Graves’ disease from January 2006 to December 2016 were evaluated.

Results

The study comprised 67 participants with a mean age of 46 years (range16–78 years). A total of 78% of patients were on methimazole, 34% on beta-blockers, 27% on potassium iodine solution, 10% on propylthiouracil and 7% on steroids. At the time of surgery 21% were in an overt hyperthyroid state and 33% were in a subclinical hyperthyroid state. The average TSH level of 0.03 mIUL/L (range 0.01–0.23 mIUL/L). Sixteen percent of patients had a TSH level less than 0.01 mIUL/L. The average free T4 level was 29.58 pmol/L (range 11.5–95.2 pmol/L). The average total T3 level was 11.52 nmol/L (range 4.5–29.1 nmol/L) and free T3 level was 6.35 pmol/L (range 6.1–6.6 pmol/L). No patient developed thyroid storm.

Conclusions

In our study, biochemically hyperthyroid patients undergoing thyroidectomy did not develop thyroid storm. Additional studies with larger sample sizes are needed to better understand the risk of thyroid storm in hyperthyroid patients.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Application of Subspace Clustering in DNA Sequence Analysis

Identification and clustering of orthologous genes plays an important role in developing evolutionary models such as validating convergent and divergent phylogeny and predicting functional proteins in newly sequenced species of unverified nucleotide protein mappings. Here, we introduce an application of subspace clustering as applied to orthologous gene sequences and discuss the initial results. The working hypothesis is based upon the concept that genetic changes between nucleotide sequences coding for proteins among selected species and groups may lie within a union of subspaces for clusters of the orthologous groups. Estimates for the subspace dimensions were computed for a small population sample. A series of experiments was performed to cluster randomly selected sequences. The experimental design allows for both false positives and false negatives, and estimates for the statistical significance are provided. The clustering results are consistent with the main hypothesis. A simple random mutation binary tree model is used to simulate speciation events that show the interdependence of the subspace rank versus time and mutation rates. The simple mutation model is found to be largely consistent with the observed subspace clustering singular value results. Our study indicates that the subspace clustering method may be applied in orthology analysis.

Improving access to dental care for vulnerable children; further development of the Back2School programme in 2013

This paper describes a service evaluation of a dental treatment programme providing care to children not normally taken to the dentist. It explains the extension of the Back2School programme from the pilot phase and assesses if a mobile dental unit (MDU) can provide a high quality service. The public health competencies it illustrates include oral health improvement, developing and monitoring quality dental services, and collaborative working.

Evaluation of lactate detection using selective multiple quantum coherence in phantoms and brain tumours

Lactate is a product of glucose metabolism. In tumour tissues, which exhibit enhanced glycolytic metabolism, lactate signals may be elevated, making lactate a potential useful tumour biomarker. Methods of lactate quantitation are complicated because of overlap between the lactate methyl doublet CH3 resonance and a lipid resonance at 1.3 ppm. This study presents the use of a selective homonuclear multiple quantum coherence transfer sequence (SelMQC-CSI), at 1.5 T, to better quantify lactate in the presence of lipids. Work performed on phantoms showed good lactate detection (49%) and lipid suppression (98%) efficiencies. To evaluate the method in the brain, the sequence was tested on a group of 23 patients with treated brain tumours, either glioma (N=20) or secondary metastases in the brain (N=3). Here it was proved to be of use in determining lactate concentrations in vivo. Lactate was clearly seen in SelMQC spectra of glioma, even in the presence of lipids, with high grade glioma (7.3 ± 1.9 mM, mean ± standard deviation) having higher concentrations than low grade glioma (1.9 ± 1.5 mM, p=0.048). Lactate was not seen in secondary metastases in the brain. SelMQC-CSI is shown to be a useful technique for measuring lactate in tumours whose signals are otherwise contaminated by lipid.

Clinical outcomes and quality of life 5 years after a randomized trial of concomitant or sequential phlebectomy following endovenous laser ablation for varicose veins

Background

Endovenous laser ablation (EVLA) is a popular treatment for superficial venous insufficiency. Debate continues regarding the optimal management of symptomatic varicose tributaries following ablation of the main saphenous trunk. This randomized trial compared the 5-year outcomes of endovenous laser therapy with ambulatory phlebectomy (EVLTAP) with concomitant ambulatory phlebectomy, and EVLA alone with sequential treatment if required following a delay of at least 6 weeks.

Methods

Patients undergoing EVLA for great saphenous vein insufficiency were randomized to receive EVLTAP or EVLA alone with sequential phlebectomy, if required. Outcomes included disease-specific quality of life (QoL) (Aberdeen Varicose Vein Questionnaire; AVVQ), requirement for secondary procedures, clinical severity (Venous Clinical Severity Score; VCSS), residual and recurrent varicose tributaries, and generic QoL. Patients were followed up for 5 years.

Results

Fifty patients were randomized equally into two parallel groups. The EVLTAP group had lower VCSS scores at 12 weeks (median 0 (i.q.r. 0–1) versus 2 (0–2); P &lt;0·001), and lower AVVQ scores at 6 weeks (median 7·9 (i.q.r. 4·1–10·7) versus 13·5 (10·9–18·1); P &lt; 0·001) and 12 weeks (2·0 (0·4–7·7) versus 9·6 (2·2–13·8); P = 0·015). VCSS and AVVQ scores were equivalent by 1 year, but only after 16 of 24 patients in the EVLA group, compared with one of 25 in the EVLTAP group (P &lt; 0·001), had received a secondary intervention. From 1 to 5 years both groups had equivalent outcomes.

Conclusion

EVLA with either concomitant or sequential management of tributaries is acceptable treatment for symptomatic varicose veins, with both treatments achieving excellent results at 5 years. Concomitant treatment of varicosities is associated with optimal improvement in both clinical disease severity and QoL.

Multi-Parametric MRI-Directed Focal Salvage Permanent Interstitial Brachytherapy for Locally Recurrent Adenocarcinoma of the Prostate: A Novel Approach

Even with the technological advances of dose-escalated IMRT with the addition of the latest image guidance technologies, local failures still occur. The combination of MRI-based imaging techniques can yield quantitative information that reflects on the biological properties of prostatic tissues. These techniques provide unique information that can be used for tumor detection in the treated gland. With the advent of these improved imaging modalities, it has become possible to more effectively image local recurrences within the prostate gland. With better imaging, these focal recurrences can be differentially targeted with salvage brachytherapy minimizing rectal and bladder toxicity. Here we report a novel use of MRI-directed focal brachytherapy after local recurrence. This technique offers a unique opportunity to safely and successfully treat recurrent prostate cancer, previously treated with definitive radiation therapy. The use of multi-parametric MRI-directed focal salvage permanent interstitial brachytherapy for locally recurrent adenocarcinoma of the prostate is a promising strategy to avoid more aggressive and expensive treatments that are associated with increased morbidity, potentially improving survival at potentially lower costs.

Measurement reproducibility of perfusion fraction and pseudodiffusion coefficient derived by intravoxel incoherent motion diffusion-weighted MR imaging in normal liver and metastases

OBJECTIVE

To determine the measurement reproducibility of perfusion fraction f, pseudodiffusion coefficient D and diffusion coefficient D in colorectal liver metastases and normal liver.

METHODS

Fourteen patients with known colorectal liver metastases were examined twice using respiratory-triggered echo-planar DW-MRI with eight b values (0 to 900 s/mm(2)) 1 h apart. Regions of interests were drawn around target metastasis and normal liver in each patient to derive ADC (all b values), ADC(high) (b values ≥ 100 s/mm(2)) and intravoxel incoherent motion (IVIM) parameters f, D and D by least squares data fitting. Short-term measurement reproducibility of median ADC, ADC(high), f, D and D values were derived from Bland-Altman analysis.

RESULTS

The measurement reproducibility for ADC, ADC(high) and D was worst in colorectal liver metastases (-21 % to +25 %) compared with liver parenchyma (-6 % to +8 %). Poor measurement reproducibility was observed for the perfusion-sensitive parameters of f (-75 % to +241 %) and D (-89 % to +2,120 %) in metastases, and to a lesser extent the f (-24 % to +25 %) and D (-31 % to +59 %) of liver.

CONCLUSIONS

Estimates of f and D derived from the widely used least squares IVIM fitting showed poor measurement reproducibility. Efforts should be made to improve the measurement reproducibility of perfusion-sensitive IVIM parameters.

Usability of tablet computers by people with early-stage dementia

BACKGROUND

Tablet computers are generally associated with an intuitive interface. The adoption and use of tablet computers within the early-stage dementia context could potentially assist in daily living and provide users with a source for leisure activities and social networking. As dementia mainly affects the older adult population, it is expected that many people with dementia and even their carers do not use tablet computers as part of their everyday living.

OBJECTIVE

This paper explores the usability of tablet computers within the early-stage dementia context as a source of leisure for people with dementia. The main advantage of the use of tablet computers in this manner is to provide carers some reprieve from the constant care and attention often required in caring for people with dementia.

METHODS

Seven-day in-home trials were conducted to determine whether people with early-stage dementia were -capable of using a tablet computer independently. Twenty-one people with early-stage dementia and carer dyads participated in the trial. Feedback was gathered through questionnaires from both the person with dementia and their carer regarding the use of a tablet computer as part of their everyday living.

RESULTS

Approximately half the participants with dementia were able to engage with and use the tablet computer independently, which proved to be helpful to their carers. No significant traits were observed to help identify those who were less likely to use a tablet computer. Carer relief was quantified by the amount of time participants with dementia spent using the device without supervision.

CONCLUSIONS

The results and feedback from the trial provide significant insights to introducing new technology within the early-stage dementia context. Users' needs must be considered on a case-by-case basis to successfully facilitate the uptake of tablet computers in the dementia context. The trial has provided sufficient justification to further explore more uses of tablet computers in the dementia context, and not just for early-stage dementia.

MEG-SIM: a web portal for testing MEG analysis methods using realistic simulated and empirical data

MEG and EEG measure electrophysiological activity in the brain with exquisite temporal resolution. Because of this unique strength relative to noninvasive hemodynamic-based measures (fMRI, PET), the complementary nature of hemodynamic and electrophysiological techniques is becoming more widely recognized (e.g., Human Connectome Project). However, the available analysis methods for solving the inverse problem for MEG and EEG have not been compared and standardized to the extent that they have for fMRI/PET. A number of factors, including the non-uniqueness of the solution to the inverse problem for MEG/EEG, have led to multiple analysis techniques which have not been tested on consistent datasets, making direct comparisons of techniques challenging (or impossible). Since each of the methods is known to have their own set of strengths and weaknesses, it would be beneficial to quantify them. Toward this end, we are announcing the establishment of a website containing an extensive series of realistic simulated data for testing purposes ( http://cobre.mrn.org/megsim/ ). Here, we present: 1) a brief overview of the basic types of inverse procedures; 2) the rationale and description of the testbed created; and 3) cases emphasizing functional connectivity (e.g., oscillatory activity) suitable for a wide assortment of analyses including independent component analysis (ICA), Granger Causality/Directed transfer function, and single-trial analysis.

Evolution of an Endovenous Laser Ablation Practice for Varicose Veins

Objective:

We aimed to assess the evolution of an endovenous laser ablation (EVLA) practice in the management of varicose veins in a university teaching hospital vascular surgical unit, over five years.

Methods:

This was a retrospective review of a prospectively collected database of patients undergoing EVLA for great saphenous vein incompetence and followed up for a year. For inter- and intragroup comparison, patients were divided into three groups: group A: endovenous access generally established at the perigenicular level ( n = 105); group B: when practice changed to gain access at lowest point of demonstrable reflux ( n = 70); and group C: when tumescence delivery changed from manual injections to delivery via peristaltic pump ( n = 49). Outcomes including pain scores, time taken to return to normal functioning, quality of life (QoL), venous clinical severity scores (VCSS) and complication rates were evaluated.

Results:

Intergroup analysis: increase in the length of vein treated and laser density delivered was observed over time, even as median procedure duration decreased ( P < 0.001). An increase in sensory disturbance was noticed in group C ( P = 0.047) while better Aberdeen Varicose Vein Questionnaire (AVVQ) ( P = 0.004), SF-36® physical domains ( P < 0.05) and patient satisfaction with treatment ( P = 0.025) were recorded in the same group at 52 weeks. No significant difference was observed in technical failure, pain scores, return to normal functioning, VCSS and recurrence rates post-intervention. Intragroup analysis: QoL measures (AVVQ, SF-36®, EQ-5D) and VCSS scores demonstrated significant improvement at 12 and 52 weeks compared with baseline ( P < 0.05).

Conclusions:

Increase in length of vein treated and energy delivery seems to improve short-term outcomes; however, operators need to be wary of a possible concurrent increase in paraesthetic complications.

Saphenopopliteal ligation and stripping of small saphenous vein: does extended stripping provide better results?

OBJECTIVE

Saphenopopliteal ligation (SPL) for venous insufficiency is a challenging procedure, with mixed results being reported. The role of stripping of the small saphenous vein (SSV) is contentious. This prospective observational study aimed to assess the risks and benefits of this procedure.

METHODS

Fifty patients underwent SPL under general anaesthesia by a single surgeon in a tertiary referral vascular centre. The aim was to perform inversion stripping in each case, but in a proportion this was not possible. Patients were grouped into SPL with short segment excision ≤5 cm (n = 23) and SPL with extended stripping >5 cm (n = 27). Outcome measures included venous clinical severity scores (VCSS), quality of life (QoL), Aberdeen varicose vein questionnaire (AVVQ), patient satisfaction, recurrence and complication rates.

RESULTS

Intragroup analysis demonstrated statistically significant improvements in VCSS (P < 0.001), and QoL measures (generic and disease-specific AVVQ) (P < 0.050) with both treatments. Intergroup analysis demonstrated statistically significant superior VCSS scores at one year (P = 0.001), AVVQ at three months and one year (P < 0.05), and cosmetic satisfaction at one year (P = 0.011) in the SPL extended stripping group. There was no difference in clinical recurrence 1/23 (4.3%) versus 1/27 (3.7%) (P = 0.900) or complication rates (P > 0.050).

CONCLUSIONS

SPL with or without stripping is an effective procedure improving clinical severity and QoL in the short term. Early outcomes favour SPL with extended stripping to offer greater improvement in disease-specific QoL, venous severity and cosmesis. With this small sample, there is no evidence of increased complications following stripping, or increased short-term recurrence without it. Greater numbers and follow-up are required to make firm conclusions.

Combining diffusion-weighted MRI with Gd-EOB-DTPA-enhanced MRI improves the detection of colorectal liver metastases

OBJECTIVES

To compare the diagnostic accuracy of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI, diffusion-weighted MRI (DW-MRI) and a combination of both techniques for the detection of colorectal hepatic metastases.

METHODS

72 patients with suspected colorectal liver metastases underwent Gd-EOB-DTPA MRI and DW-MRI. Images were retrospectively reviewed with unenhanced T(1) and T(2) weighted images as Gd-EOB-DTPA image set, DW-MRI image set and combined image set by two independent radiologists. Each lesion detected was scored for size, location and likelihood of metastasis, and compared with surgery and follow-up imaging. Diagnostic accuracy was compared using receiver operating characteristics and interobserver agreement by kappa statistics.

RESULTS

417 lesions (310 metastases, 107 benign) were found in 72 patients. For both readers, diagnostic accuracy using the combined image set was higher [area under the curve (Az)=0.96, 0.97] than Gd-EOB-DTPA image set (Az=0.86, 0.89) or DW-MRI image set (Az=0.93, 0.92). Using combined image set improved identification of liver metastases compared with Gd-EOB-DTPA image set (p<0.001) or DW-MRI image set (p<0.001). There was very good interobserver agreement for lesion classification (κ=0.81-0.88).

CONCLUSIONS

Combining DW-MRI with Gd-EOB-DTPA-enhanced T(1) weighted MRI significantly improved the detection of colorectal liver metastases.

Comparing the treatment response of great saphenous and small saphenous vein incompetence following surgery and endovenous laser ablation: a retrospective cohort study

Objective

Many venous trials mix patients with great saphenous vein (GSV) and small saphenous vein (SSV) diseases. There is no evidence that both respond similarly to treatment and our aim was to test this assumption.

Method

This cohort study compares patients with isolated GSV and SSV incompetence following treatment with open surgical ligation or endovenous laser ablation (EVLA). Outcomes included: quality of life (QoL; Aberdeen Varicose Vein Questionnaire [AVVQ]; Short Form 36 [SF36]; Euroqol [EQ5D]; and Venous Clinical Severity Score [VCSS]).

Results

A total of 370 patients with no differences in baseline QoL, underwent treatment. Despite equivalent morbidity, SSV sufferers had a lower VCSS ( P < 0.001). Following surgery, SSV patients scored higher (worse) on AVVQ ( P = 0.045) than GSV sufferers, but lower (better) following EVLA ( P = 0.042).

Conclusion

The morbidity associated with SSV incompetence is greater than suggested by its clinical severity and responds differently following treatment to that of the GSV. Trials should consider patients with GSV and SSV reflux separately. EVLA may offer additional benefits to SSV sufferers.

Segmental liver hyperintensity in malignant biliary obstruction on diffusion weighted MRI: associated MRI findings and relationship with serum alanine aminotransferase levels

OBJECTIVES

Segmental liver hyperintensity can be observed in malignant biliary obstruction on diffusion weighted MRI (DW-MRI). We describe MRI findings associated with this sign and evaluate whether DW-MRI segmental hyperintensity has any relationship with serum alanine aminotransferase (ALT) levels.

METHODS

The DW-MRI T(1) weighted, T(2) weighted and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced T(1) weighted images obtained in 21 patients with hepatic malignancy, who demonstrated biliary obstruction and segmental hyperintensity on DW-MRI (b=0-750 s mm(-2)), were retrospectively reviewed by 2 readers blinded to clinical results. DW-MRI hyperintense liver segments were recorded as hypointense, isointense or hyperintense relative to normal liver on T(1)/T(2) weighted imaging. It was also noted whether contrast enhancement was similar to that observed in normal liver or diminished in the hepatocellular phase. The mean apparent diffusion coefficient (ADC) value (×10(-3) s mm(-2)) of DW-MRI hyperintense segments, normal liver and tumour were compared using Student's t-test. The frequency of MRI findings was corroborated with serum ALT levels, which reflect hepatocyte injury.

RESULTS

DW-MRI hyperintense segments frequently showed T(1) hyperintensity (10/21), T(2) hyperintensity (19/21) and/or diminished contrast enhancement (15/21). Tumours showed significantly lower mean ADC values than liver (1.23 ± 0.08 vs 1.43 ± 0.05; p=0.013). Segments showing concomitant T(1) hyperintensity had lower mean ADC values than liver (1.30 ± 0.05 vs 1.43 ± 0.05; p=0.023). The patients (8/10) with concomitant T(1) and DW-MRI segmental hyperintensity showed elevated ALT levels (p=0.030, Fisher's exact test).

CONCLUSION

Concomitantly high T(1) weighted and DW-MRI signal in liver segments was associated with lower ADC values and abnormal liver function tests, which could reflect underlying cellular swelling and damage.

Smoking during pregnancy: postnatal effects on arousal and attentional brain systems

Prenatal exposure to cigarette smoke is known to produce lasting arousal, attentional and cognitive deficits in humans. The pedunculopontine nucleus (PPN), as the cholinergic arm of the reticular activating system (RAS), is known to modulate arousal, waking and REM sleep. Rapid eye movement (REM) sleep decreases between 10 and 30 days postnatally in the rat, with the greatest decrease occurring at 12-21 days. Pregnant dams were exposed to 150 ml of cigarette smoke for 15 min, three times per day, from day E14 until parturition, and the pups allowed to mature. We analyzed (a) intrinsic membrane properties of PPN neurons in slices from pups aged 12-21 days, and (b) the sleep state-dependent P13 auditory evoked potential, which is generated by PPN outputs, in animals allowed to age to adolescence. We found significant changes in the intrinsic membrane properties of PPN cells in prenatally exposed animals compared to intact ones, rendering these cells more excitable. In addition, we found disturbances in the habituation to repetitive stimulation in adolescent, freely moving animals, suggestive of a deficit in the process of sensory gating. These findings could explain some of the differences seen in individuals whose parents smoked during pregnancy, especially in terms of their hypervigilance and increased propensity for attentional deficits and cognitive/behavioral disorders.

Venous thromboembolic disease: a single-centre case series study

AIM

The epidemiology of venous thromboembolism in children has likely changed since first being described a decade ago because of evolving management strategies and a greater awareness of predisposing factors for thrombosis in children. The Royal Children's Hospital commenced a 4-year prospective registry of venous thrombosis in 1999 to determine the current Australian epidemiology of venous thrombosis in infants and children.

METHODS

A prospective, single-centre registry was established to determine the prevalence, aetiology, diagnostic criteria, management and outcome of venous thromboembolism in an Australian tertiary paediatric centre.

RESULTS

The incidence of venous thrombosis was 8.0/10 000 hospital admissions. Fifty-eight per cent of infants and 49% of children were male. Seventy-seven per cent of venous thromboses in infants were associated with central venous cannulation compared with 47% in children. Doppler ultrasonography was the most frequently used diagnostic tool. Treatment strategies varied between age groups. The all-cause mortality rate for infants and children in this study was 8.4% (direct thrombus-related mortality 0%). Fifteen per cent of all patients demonstrated complete resolution of their venous thrombosis at discharge, with 48% demonstrating complete resolution at follow-up assessment. Fifteen per cent of patients experienced significant thrombosis-related morbidity at follow-up assessment.

CONCLUSION

In this single-centre registry, venous thrombosis in infants and children occurred with greater frequency than has previously been reported and its epidemiology varied. Central venous catheterisation continues to be a common precipitant to venous thrombosis. Optimal diagnostic and treatment interventions for venous thromboembolism have not yet been determined for infants and children, despite the significant incidence of long-term sequelae.

Nicotine suppresses the P13 auditory evoked potential by acting on the pedunculopontine nucleus in the rat

We identified a potential novel site of action for nicotine (NIC) since (a) systemic injection of NIC led to a dose-dependent decrease in the amplitude of the sleep state-dependent, vertex-recorded, P13 midlatency auditory evoked potential (generated by the reticular activating system, RAS), (b) localized injections of a nicotinic receptor antagonist into the pedunculopontine nucleus (PPN, the cholinergic arm of the RAS) blocked the effects of systemic NIC on the P13 potential (a measure of level of arousal), and (c) localized injection of a nicotinic receptor agonist into the PPN also led to a decrease in the amplitude of the P13 potential, an effect blocked by PPN injection of a nicotinic receptor antagonist. There were minor changes in the manifestation of the startle response (SR) at the concentrations used; however, NIC did decrease the hippocampal N40 potential, although its effects were not affected by antagonist or agonist injections into the PPN. These results suggest a potential mechanism underlying the anxiolytic effects of NIC-suppression of the cholinergic arm of the RAS.

Differential antifungal activity of isomeric forms of nystatin

When nystatin is placed in RPMI and other biological fluids, there is loss of pure nystatin, with the development of two distinguishable chromatographic peaks, 1 and 2. Peak 1 appears identical to commercially prepared nystatin. By nuclear magnetic resonance (NMR) and mass spectral analysis, peak 2 appears to be an isomer of peak 1. The isomers are quantitatively and fully interconvertible. Formation of peak 2 is accelerated at a pH of >7.0 and ultimately reaches a near 55:45 (peak 1/peak 2 ratio) mixture. We sought to determine the relative activities of peaks 1 and 2 against Candida spp. Peak 2 consistently showed higher MICs when it was the predominant form during the experiment. Time-kill analyses showed that peak 2 required > or =8 x the concentration of peak 1 to produce a modest and delayed killing effect, which was never of the same magnitude as that produced by peak 1. In both types of assays, the activity of peak 2 corresponded with intra-assay formation of peak 1. Both MIC measurements and time-kill analysis suggest that peak 2 has considerably less activity, if any at all, against Candida spp. Peak 2 may serve as a reservoir for peak 1.

Subduction and collision processes in the Central Andes constrained by converted seismic phases

The Central Andes are the Earth's highest mountain belt formed by ocean-continent collision. Most of this uplift is thought to have occurred in the past 20 Myr, owing mainly to thickening of the continental crust, dominated by tectonic shortening. Here we use P-to-S (compressional-to-shear) converted teleseismic waves observed on several temporary networks in the Central Andes to image the deep structure associated with these tectonic processes. We find that the Moho (the Mohorovicić discontinuity--generally thought to separate crust from mantle) ranges from a depth of 75 km under the Altiplano plateau to 50 km beneath the 4-km-high Puna plateau. This relatively thin crust below such a high-elevation region indicates that thinning of the lithospheric mantle may have contributed to the uplift of the Puna plateau. We have also imaged the subducted crust of the Nazca oceanic plate down to 120 km depth, where it becomes invisible to converted teleseismic waves, probably owing to completion of the gabbro-eclogite transformation; this is direct evidence for the presence of kinetically delayed metamorphic reactions in subducting plates. Most of the intermediate-depth seismicity in the subducting plate stops at 120 km depth as well, suggesting a relation with this transformation. We see an intracrustal low-velocity zone, 10-20 km thick, below the entire Altiplano and Puna plateaux, which we interpret as a zone of continuing metamorphism and partial melting that decouples upper-crustal imbrication from lower-crustal thickening.

Is surgical excision necessary for atypical ductal hyperplasia of the breast diagnosed by Mammotome?

BACKGROUND

Core biopsy findings of atypical ductal hyperplasia (ADH) underestimates the diagnosis of malignancy by 18% to 88%. Using the Mammotome biopsy technique, more accurate assessment of the lesion is possible, making selective excision of these lesions a consideration.

METHODS

The records of 62 patients who were found to have ADH at Mammotome biopsy and subsequently underwent excision of the lesion were reviewed. Patient data were statistically analyzed for predictors of malignancy at the time of surgical excision.

RESULTS

Of the 62 patients, 9 (15%) had malignancy at excision. Variables predicting for malignancy included markedly atypical hyperplasia and incomplete removal of calcifications at Mammotome biopsy, a previous contralateral breast cancer, and a family history of breast cancer, with a combined sensitivity of 100% and specificity of 80%.

CONCLUSIONS

Mild ADH found on Mammotome, not associated with a personal or family history of breast cancer, may not need excision if all calcifications have been removed.

Methamphetamine selectively alters brain glutathione

As methamphetamine-induced neurotoxicity has been proposed to involve oxidative stress, reduced and oxidized glutathione (GSH and GSSG, respectively), vitamin E and ascorbate were measured in the striata of rats killed 2 or 24 h after a neurotoxic regimen of methamphetamine. At 2 h, methamphetamine increased GSH and GSSG (32. 5% and 43.7%, respectively) compared to controls at 2 h. No difference was seen in glutathione at 24 h, and in vitamin E and ascorbate at either time point. These findings indicate selectivity of methamphetamine for the glutathione system and a role for methamphetamine in inducing oxidative stress.

Influence of changes in gravity on the response of lung and vascular cells to ischemia/reperfusion in vitro

Gravity and other physical forces (e.g., shear stress or mechanical stretch) will affect organ and cellular function, e.g., blood flow distribution, gas exchange, alveolar size and mechanical stresses within the lung. Microgravity produced marked alterations in lung blood flow and ventilation distribution while hypergravity exaggerated the regional differences in lung structure and function. Microgravity was found to decrease the metabolic activity in cardiac cells, WI-38 embryonic lung cells, and human lymphocytes. These studies show that changes in gravity will affect several aspects of organ and cellular function and produce major changes in blood flow and tissue/organ perfusion. However, these past studies have not addressed whether ischemia-reperfusion injury will be exacerbated or, ameliorated by changes in the gravity environment, e.g., space flight. Currently, nothing is known about how gravity will affect the susceptibility of different lung and vascular cells to this type of injury. Ischemia injury is the underlying cause of many clinical disorders with high morbidity and mortality. The subsequent reperfusion (reoxygenation) further compounds the initial ischemic stress. Understanding the possible exacerbation of transient ischemia under the stress of space flight or an increase in gravity is critical. We conducted studies that examined whether alterations in gravity affect the susceptibility of cells to ischemia-reperfusion injury, using an in vitro anoxia-reoxygenation model.