The Relationship between Nociceptive Detection Thresholds and Pressure- and Electrical Pain Thresholds: An Explorative Study in Rheumatoid Arthritis Patients

Recently, methods have been developed enabling the characterization of the nociceptive function at the detection threshold level by measuring nociceptive detection thresholds (NDTs), rather than at the level of the pain threshold via pain threshold (PT) measurements. Both NDT and PT measurements aim to characterize (parts of) the nociceptive system. To date it is unclear if, and if so to what extent, the two outcomes relate to one another. In this study, the primary aim is to explore the relationship between the two measures in patients with rheumatoid arthritis (RA). As secondary aim, we explore differences in NDT between these RA patients with age- and sex-matched healthy controls (HC) from a readily existing dataset. In total 46 RA patients have been recruited, whereby the pressure- (PPT; bilaterally at two locations) and electrical (EPT) pain threshold were evaluated, as well as the NDTs. Significant, positive correlations were found between the EPT and PPT (R=0.54-0.60), but not with the NDTs (R≤0.25). As compared to HC, higher NDTs were found in the RA group. As the presence of a statistically significant weak relationship can only be evaluated using a larger sample size, our results indicate that there is no moderate or stronger relation between PT and NDT outcomes. This implicates that the two outcomes are not strongly driven by the same (nociceptive) mechanism(s). Future research into NDTs and what factors and/or mechanisms affect the outcome, could yield relevant insights into how to use and interpret the results of this relatively new method.Clinical Relevance - The evaluation of nociceptive detection thresholds, in isolation or together with conventionally evaluated pain thresholds, might provide valuable and complementary insights into nociceptive (dis)function in man.

Organ Donation After Euthanasia in Patients Suffering From Psychiatric Disorders: 10-Years of Preliminary Experiences in the Netherlands

Euthanasia based on psychiatric suffering, followed by subsequent organ donation, is considered medically and legally permissible in the Netherlands. Although organ donation after euthanasia (ODE) in patients suffering from unbearable psychiatric illness is performed, it is not specifically addressed in the Dutch guideline on organ donation after euthanasia, and national data on ODE in psychiatric patients have not yet been published. In this article, the preliminary results of the 10-year Dutch case series of psychiatric patients who choose ODE are presented and potential factors influencing opportunities for donation in this population are discussed. We conclude that further future in-depth qualitative exploration of ODE in patients suffering from psychiatric illness and its associated ethical and practical dilemmas, including the consequences for the patient and their family and healthcare professionals, will be important to help make sense of potential barriers to donation for people undergoing euthanasia as a result of psychiatric suffering.

The integrated GOR-COVID-19 health monitor: protocol for a comprehensive approach

Introduction

The global COVID-19-pandemic influences people's health, both directly through infection and indirectly through the protective measures taken by governments. Previous experience with health research after disasters/crises are generally limited to short-lasting, local disasters with direct consequences for those affected. The COVID-19-pandemic has a different nature: influencing everyone and lasting a longer time. A longitudinal, wide-reaching research-approach is needed to study the health effects of COVID-19. Therefore, the Network GOR-COVID-19, a research group consisting of different organizations, started a monitor on the health effects of COVID-19.

Methods

The monitor consists of three main elements: yearly monitoring, quarterly monitoring and literature reviews. Where possible, existing data structures are used. For the quarterly monitoring, two data sources are used: general practitioners’ [GP] registry data and data gathered from panels. The GP data is used for weekly surveillance, giving insight into the prevalence of health symptoms presented to the GP. The panel data is used to gain insight into current self-reported health and wellbeing of people. For the yearly monitoring, two data sources are used. The first is GP data which gives information about the prevalence, incidence and development of symptoms, complaints and diagnoses. It allows for comparison over time and among different population groups. The second is the corona health monitor questionnaire, an existing questionnaire on health and well-being. Finally, literature reviews are conducted annually to create an overview of international and national research about the effects of the COVID-19-pandemic on health.

Discussion

Since most of our knowledge about the potential impact of the pandemic stems from research on short-term disasters, limited to specific places, this study is expected to provide valuable new insights.

The integrated GOR-COVID-19 health monitor: research-informed policy-making through dialogue

Introduction

Like in many other countries, the COVID-19 pandemic and the government restrictions introduced to contain the spread of the virus had major consequences for the health and wellbeing of the population in the Netherlands. To monitor the short and long-term public health impact, a nationally coordinated research program was initiated with the intention to guide decision-making by local and national public health authorities. This contribution presents the process to establish a continuous dialogue with end-users of information to add focus to the monitor, make sense of the findings and formulate policy recommendation and practical guidance, both at the national and regional level.

Methods

To facilitate the translation and dissemination of research results among policy makers, practitioners and scientists, an ongoing series of dialogue sessions is organized during the monitoring program. Apart from the objective of evidence-informed public health decision-making, the dialectic process seeks to ensure multi-sectoral learning and co-creation and contribute to a broad sense of ownership among stakeholders. National and regional health participants serve as hub coordinators. New stakeholders are invited and will be actively approached wherever considered relevant.

Results

At the EUPHA conference experiences with organizing the dialogue in app. the first two years of the program will be presented together with preliminary results and a reflection on factors that helped or hindered the implementation and uptake of findings.

Discussion

Monitoring data collected using robust methods and analyzed in such a way that vulnerability factors are carefully considered, is invaluable for decision-making. However, in order to effectively serve as guidance to public health policy, whether in the context of the COVID-19 pandemic or in non-crisis situations, a constructive, ongoing exchange between end-users of the information needs to be facilitated.

An Inventory of Deceased Donor Family Care and Contact Between Donor Families and Recipients in 15 European Countries

Families of organ donors play an important role in the deceased organ donation process. The aim of this study was to gain insight into donor family care by creating an inventory of practice in various European countries. A questionnaire about donor family care and contact between donor families and recipients was developed. Representatives of the organ donor professionals of 15 European countries responded (94%). The donor coordinator plays a key role in care for the donor family. All countries provide information about the donation results to the families, although diminished due to privacy laws. Anonymous written contact between donor families and recipients is possible in almost all countries and direct contact in only a few. Remembrance ceremonies exist in most countries. Half of the respondents thought the aftercare could improve. This first inventory shows that differences exist between countries, depending on the organisation of the donation process, the law and the different role of the professionals. Direct contact between donor families and recipients is rarely supported by the donation organisation. To date there has been limited research about the experience of donor family aftercare and we would urge all donation organisations to consider this as a priority area.

Building a bridge between patients and transplant healthcare professionals - a descriptive study

This article describes a pathway for collaboration between transplant healthcare professionals and organ recipients. Under the umbrella of the European Society for Organ Transplantation (ESOT) a joint initiative started from three Sections and Committees of ESOT: EDTCO (European Donation and Transplant Coordination Organisation), ETHAP (European Transplant Allied Healthcare Professionals) and ELPAT (Ethical, Legal and Psycho-social Aspects of Transplantation). The formal 'kick-off' of the Advisory Board Meeting of the European Transplant Patient Organisation (ETPO) was during the ESOT congress in 2019. The aim was to produce a series of statements to serve as a path to dialogue between patients and transplant professionals and to define the next steps towards giving a voice to the patient network. To include the patients' perspectives, two surveys have been performed. The results identified the unmet needs and lead to a proposal for future plans. Educational activities have since started leading to a patient learning workstream. All initiatives taken have one purpose: to include patients, give them a voice and build a foundation for collaboration between patients and transplant professionals. ESOT has created a platform for mutual understanding, learning and a collaborative partnership between ETPO and European donation and transplant professionals.

Factors associated with erectile dysfunction diagnosis in men with HIV infection: a case-control study

OBJECTIVES

HIV infection is associated with increased risk of erectile dysfunction (ED); however, factors associated with ED remain unclear. We evaluated the prevalence of ED among men living with HIV and factors associated with ED diagnosis in the US Military HIV Natural History Study (NHS).

METHODS

A retrospective cohort study evaluated participants in the NHS, a cohort of HIV-positive active duty members and beneficiaries with HIV infection. Men with a diagnosis of ED after HIV diagnosis were included. Cohort controls without ED diagnosis were matched 2:1 by age at HIV diagnosis and duration of follow-up. Multivariate logistic regression models were used to identify factors associated with ED.

RESULTS

A total of 543 of 5682 male participants (9.6% prevalence) had a diagnosis of ED, of whom 488 were included in the analysis. The median (interquartile range, IQR) age at ED diagnosis was 43 (37.0-49.0) years and the time from HIV diagnosis to antiretroviral therapy (ART) start was longer for cases (5.0 years, IQR: 2.0-9.0) than for controls (3.0 years, 1.0-6.0; P < 0.01). Cases had higher proportions of multiple comorbid conditions, including depression (33.4% vs. 21.7%), tobacco use (19.7% vs. 9.0%) and sleep apnoea (14.8% vs. 4.2%) compared with controls (P < 0.01 for all). Logistic regression showed increased odds of ED for delayed ART initiation > 4 years [odds ratio (OR) = 2.05, 95% confidence interval (CI): 1.56-2.71], protease inhibitor use ≥ 1 year (OR = 1.81, 95% CI: 1.38-2.38) and sleep apnoea (OR = 2.60, 95% CI: 1.68-4.01).

CONCLUSIONS

Erectile dysfunction was common in men with HIV and associated factors included both HIV-related and traditional factors.

P1618DEVELOPMENT AND EXTERNAL VALIDATION OF A PREDICTION MODEL FOR ADVERSE OUTCOME FOLLOWING KIDNEY TRANSPLANTATION FROM OLDER DECEASED DONORS

Background and Aims

With rising demand for kidney transplantation and the kidney donor pool lagging behind, the acceptance criteria for donor kidneys are expanding. Hence, reliable pre-transplant assessment of organ quality has become a top priority. Estimating the risk of adverse outcomes at the time of kidney allocation is challenging and particularly relevant for recipients of kidneys from older donors. The existing kidney donor risk index (KDRI) has been criticized for heavily depending on donor age. Therefore, the aim of the current study was to develop and validate a prediction model for adverse outcome after kidney transplantation from deceased donors aged 50 years or older and compare this model’s performance to the KDRI.

Method

We utilized the Dutch kidney transplant registry (NOTR) and identified patients who received a kidney from a deceased donor aged 50 years or older between 2006 and 2019. These recipients were included for model development and temporal validation. The prediction model was externally validated on the United States organ transplantation registry (OPTN), in which we selected patients that were transplanted between 2006 and 2017. Potential pre-transplant predictors were selected by an expert panel of nephrologists and surgeons. The predicted adverse outcome was defined as a composite of graft failure, recipient mortality or CKD stage 4/5 within 1 year of transplantation. A logistic regression model was developed, internally validated and shrunk for optimism through bootstrapping. Missing data were multiply imputed in 10-fold, non-linear continuous predictors were modelled with restricted cubic splines and clinically relevant interaction terms were included. The KDRI was validated on the same NOTR and OPTN cohorts for graft survival within 1 year. The developed model and the KDRI were recalibrated to the baseline risk of outcome in external validation. Model performance was assessed by discrimination and calibration.

Results

The model was developed on 2510 patients of whom 823 experienced an adverse outcome within the first year. The temporal validation cohort contained 837 patients of whom 230 had an adverse outcome and the US external validation cohort consisted of 31987 patients with 6758 adverse outcomes. Selected donor predictors were: age, gender, BMI, cause of death, CPR, inotropes use, serum creatinine, hypertension, hypotension, diabetes, smoking, left/right kidney, warm ischemic time, cold ischemic time and proteinuria. Recipient predictors were: age, gender, BMI, diabetes, cardiovascular comorbidity, primary kidney disease, dialysis duration, number of previous kidney transplantations, HLA mismatches and PRA. Discrimination of the adverse outcome model was moderate, yet considerably better than discrimination of the KDRI (see table). The adverse outcome model’s calibration and distribution of predicted risks were good in both the NOTR and OPTN (see figure).

Conclusion

A prediction model was developed and extensively validated for adverse outcome after kidney transplantation from older deceased donors. Despite the use of advanced and robust methodology, its discriminatory capacity was limited. However, the adverse outcome model showed good calibration and performed considerably better than the KDRI in this population of suboptimal donors. This model could potentially assist nephrologists in deciding whether to accept or decline a specific kidney from an older deceased donor.

[Cochlear implantation with deep brain or occipital nerve stimulation : Case studies for parallel application]

We were able to demonstrate that simultaneous treatment of a patient with a neuromodulation device for deep brain stimulation (DBS) or occipital nerve stimulation (ONS) plus a cochlear implant is a possible treatment option, and that both systems are able to work within their specifications without interference from each other. A large patient population with indications for both systems could profit from this in the future.

Family overrule of registered refusal to donate organs

It is well known that families frequently overrule the wishes of dying patients who had previously expressed a wish to donate their organs. Various strategies have been suggested to reduce the frequency of these 'family overrules'. However, the possibility of families overruling a patient's registered decision not to donate has not been discussed in the medical literature, although it is legally possible in some countries. In this article, we provide an ethical analysis of family overrule of a relative's refusal to donate, using the different jurisdictions of the UK, Switzerland, Germany and the Netherlands to provide some context. Despite some asymmetries between overruling consent and overruling refusal, there are some cases in which donation should proceed despite a recorded refusal to do so.

[Atypical metastasis from a colorectal cancer : the pons is undermined !]

Brain metastases occur in 1 to 4 % of patients with colorectal cancer and are unique in 0.5 % of them. Because of their infrequent nature, brain imaging is not recommended in the systematic follow-up of these patients. We report here an exceptional case of a unique brain metastasis in a very unusual position. An 82-year-old patient with a colorectal cancer of the splenic angle that was treated with surgery and adjuvant chemotherapy, developed a series of neurological symptoms over four to six weeks: difficulty swallowing, loss of strength in the four limbs and balance disorders. These symptoms urged the performance of a nuclear magnetic resonance to exclude a central neurological lesion. MRI revealed a nodular tumor of 20 millimeters in the major transverse axis and 17 millimeters in the cerebro-caudal axis, located on the ventral portion of the protuberance. Because of its localization, surgery was not possible and the lesion was treated with Cyberknife radiosurgery. Thanks to the treatment, the lesion decreased in size and the symptoms improved significantly. Despite an initially very poor prognosis in view of the localization of the metastasis, the patient is alive and in excellent general condition more than eight months after the diagnosis of recurrence.

Cross-border collaboration for improved tuberculosis prevention and care: policies, tools and experiences

As tuberculosis (TB) spreads beyond borders with people movements, several interventions ensuring the continuity of care are essential, although difficult to put in place in the absence of well-defined agreements allowing data sharing and easy referral of patients to appropriate health facilities. This article first sets out general principles for cross-border collaboration and continuity of care. It then presents a series of case studies. Policies and practices on cross-border collaboration in selected low-incidence countries (Australia, Italy, Norway, The Netherlands, the United Kingdom and the United States) are described and critically appraised. Details of the World Health Organization's (WHO's) European Respiratory Society TB Consilium for transborder migration and those of the Health Network's TBNet activities are described. With increasing population movement, including migrants and travellers, it is time to build on good practices and existing tools and to remove legal, financial and social barriers to ensure early diagnosis, full treatment and continuity of care across our world. Data sharing between the sending and the receiving countries is of utmost importance and must be conducted in line with privacy protection rules. Successful implementation of these interventions is key to being on track with the WHO's End TB strategy targets for 2030.

13C-sodium acetate breath test for evaluation of gastric emptying times in dogs with gastric dilatation-volvulus

Objective: The aim of the study was to assess solid phase gastric emptying via non-invasive 13C-sodium acetate breath test in large breed dogs with or without gastric dilatation-volvulus (GDV). Material and methods: Dogs were recruited into one of the following groups: group 1 = healthy large breed dogs with no history of GDV, group 2 = dogs that underwent elective abdominal surgery for reasons unrelated to the gastrointestinal tract, and group 3 = dogs that underwent laparotomy and gastropexy to correct GDV. The dogs were fed a test meal containing 100 mg 13C-sodium acetate (for group 2 and 3, this was < 48 hours post-operatively). Breath samples were obtained at baseline and every 30 minutes for 3 hours, then every hour for a total of 7 hours. 12CO2/13CO2 ratio was measured for each breath sample via non-dispersive infrared spectroscopy and 25%, 50% and 75% gastric emptying times were calculated and compared between groups. Results: Gastric emptying times were significantly prolonged in dogs undergoing surgery (group 2) compared to group 1 and 3. Also, gastric emptying times of dogs with GDV were significantly prolonged compared to controls, but not to the same extent as dogs in group 2. Conclusion and clinical significance: There was a significant effect of abdominal surgery on gastric emptying times. Surprisingly, dogs after GDV surgery and gastropexy had shorter gastric emptying times than dogs undergoing laparotomy for reasons other than GDV, but still prolonged compared to healthy controls. The reason for these differences requires further study.

Prediction of GTV median dose differences eases Monte Carlo re-prescription in lung SBRT

BACKGROUND AND PURPOSE

The use of Monte Carlo (MC) dose calculation algorithm for lung patients treated with stereotactic body radiotherapy (SBRT) can be challenging. Prescription in low density media and time-consuming optimization conducted CyberKnife centers to propose an equivalent path length (EPL)-to-MC re-prescription method based on GTV median dose. Unknown at the time of planning, GTV D50% practical application remains difficult. The current study aims at creating a re-prescription predictive model in order to limit conflicting dose value during EPL optimization.

MATERIAL AND METHODS

129 patients planned with EPL algorithm were recalculated with MC. Relative GTV_D50% discrepancies were assessed and influencing parameters identified using wrapper feature selection. Based on best descriptive parameters, predictive nomogram was built from multivariate linear regression. EPL-to-MC OARs near max-dose discrepancies were reported.

RESULTS

The differences in GTV_D50% (median 10%, SD: 9%) between MC and EPL were significantly (p < .001) impacted by the lesion's surface-to-volume ratio and the average relative electronic density of the GTV and the GTV's 15 mm shell. Built upon those parameters, a nomogram (R2 = 0.79, SE = 4%) predicting the GTV_D50% discrepancies was created. Furthermore EPL-to-MC OAR dose tolerance limit showed a strong linear correlation with coefficient range [0.84-0.99].

CONCLUSION

Good prediction on the required re-prescription can be achieved prior planning using our nomogram. Based on strong linear correlation between EPL and MC for OARs near max-dose, further restriction on dose constraints during the EPL optimization can be warranted. This a priori knowledge eases the re-prescription process in limiting conflicting dose value.

Conscientious objection to deceased organ donation by healthcare professionals

In this article, we analyse the potential benefits and disadvantages of permitting healthcare professionals to invoke conscientious objection to deceased organ donation. There is some evidence that permitting doctors and nurses to register objections can ultimately lead to attitudinal change and acceptance of organ donation. However, while there may be grounds for conscientious objection in other cases such as abortion and euthanasia, the life-saving nature of donation and transplantation renders objection in this context more difficult to justify. In general, dialogue between healthcare professionals is a more appropriate solution, and any objections must be justified with a strong rationale in hospitals where such policies are put in place.

Radiological and clinical outcome of arthroscopic labral repair with all-suture anchors

PURPOSE

The aim of this study was to assess radiological and clinical outcome after arthroscopic all--suture anchor labral repair.

METHOD

20 patients treated for anterior and superior labral instability (mean age 29, range 14-51 years) were assessed at a minimum follow-up time of 1 year (mean 19 months ; range, 12-28 months). Postoperative MRI scans were assessed by 3 independent radiologists. The radiological appearance of bone at the anchor-site was judged by the presence of cyst formation, tunnel widening (> 2 mm) or bone edema. Clinical outcome analysis included standard follow-up and the Disabilities of the Arm, Shoulder and Hand score (DASH), Constant Shoulder score and the Western Ontario Shoulder Instability Index (WOSI).

RESULT

All patients were available for follow-up. In total, 58 all-suture anchors were implanted. None of the patients displayed large cyst formation. Small cysts were found in two patients (2 anchors). Tunnel widening was apparent in 3 patients (3 anchors) with an average widening of 3.3 mm (range 3-4 mm). Bone edema at the anchor-site was seen in 6 patients (8 anchors). The remaining 9 patients (45 anchors) did not display reactive bone changes. Clinical outcomes showed a WOSI of 70.6, a DASH of 18.9 and a Constant score of 89.3, and no recurrence of instability.

CONCLUSIONS

Satisfying radiological and clinical outcome was observed after arthroscopic instability surgery using all-suture anchors. Imaging revealed good labral healing without important bony reactions or the formation of large cysts at early follow-up. Level of evidence : IV Case series.

Controlled donation after circulatory death in the Netherlands: more organs, more efforts

BACKGROUND

The Netherlands was one of the first countries in Europe to stimulate controlled donation after circulatory death (cDCD) at a national level in addition to donation after brain death (DBD). With this program the number of organ transplants increased, but it also proved to have challenges as will be shown in this 15-year review.

METHODS

Data about deceased organ donation in the Netherlands, from 2000 until 2014, were analysed taking into account the whole donation process from donor referral to the number of organs transplanted.

RESULTS

Donor referral increased by 58%, from 213 to 336 donors per year, and the number of organs transplanted rose by 42%. Meanwhile the contribution of cDCD donors increased from 14% in 2000 to 54% in 2014 among all referrals. The organs were transplanted from 92-99% of referred DBD donors, but this percentage was significantly lower for cDCD donors and also decreased from 86% in 2000-2002 to 67% in 2012-2014. In 16% of all referred cDCD donors, organs were not recovered because donors did not die within the expected two-hour time limit after withdrawal of life- upporting treatment. Furthermore, cDCD is more often performed at a higher donor age, which is associated with a lower percentage of transplanted organs.

CONCLUSION

Although cDCD resulted in more transplants, the effort in donor recruitment is considerably higher. Important challenges in cDCD that need further attention are the time limit after withdrawal of life-supporting treatment and donor age, as well as the possibilities to stimulate non-renal transplants including the heart by machine preservation.

[PET-MR in patients with glioblastoma multiforme]

Glioblastoma multiforme (GBM) is the most common and most aggressive primary tumor of the brain. In recent years newer therapeutic approaches have been developed. To allow for an optimized treatment planning it is important to precisely delineate necrotic tissue, edema and vital tumor tissue and to identify the most aggressive parts of the GBM. The magnetic resonance (MR) portion of an MR-positron emission tomography (PET) examination in patients with GBM should consist of both structural and functional sequences including diffusion-weighted and perfusion sequences. The use of (18)F-fluorodeoxyglucose ((18)F-FDG) is limited in patients with gliomas as glucose metabolism is already physiologically high in parts of the brain but (18)F-FDG is nevertheless a commonly used radiopharmaceutical for neuro-oncological questions. (18)F-fluorothymidine reflects the cellular activity of thymidine kinase 1 and correlates with the expression of KI-67 as an index of mitotic activity. The nitroimidazole derivatives (18)F-fluoromisonidazole and (18)F-fluoroazomycin arabinoside ((18)F-FAZA) allow the detection of hypoxic areas within the tumor. In recent years amino acid tracers, such as (18)F-fluoroethyltyrosine are increasingly being used in the diagnosis of gliomas. The simultaneous PET-MR image acquisition allows new approaches, e.g. motion correction by the simultaneous acquisition of MR data with a high temporal resolution and an improved quantification of the PET signal by integrating the results of functional MR sequences. Moreover, the simultaneous acquisition of these two time-consuming methods leads to reduced imaging times for this, often severely ill patient group.

[Pre- or postoperative adjuvant radiotherapy for soft tissue sarcomas of limbs]

Soft tissue sarcomas are rare tumours requiring a multidisciplinary approach of the diagnostic process, the treatment and the follow up. Radical surgery remains the basis of the oncological treatment. Adjuvant radiotherapy is often added to surgery because of a high risk of local recurrence for specified patient groups. Nowadays, the adjuvant approach is often replaced by a neo-adjuvant approach as this pre-operative radiotherapy offers several advantages. We will also discuss the adaptation of the surgery to the radiotherapy and vice versa, and we present the clinical pathway for most of soft tissue sarcoma patients. We conclude with a series of technical innovations.

[The therapeutic potential of ablative radiotherapy for metastatic renal cell cancer: a tumour deemed radiation resistant]

Image guided Stereotactic Body Radiation Therapy (SBRT), is a valuable alternative to other ablative approaches, especially in the context of metastatic renal cell carcinoma (mRCC). The efficacy of this treatment depends on the Biological Effective Dose (BED). The BED is determined by total dose and dose per fraction. The technical possibility of applying high dose per fraction (> 8-10 Gy), yielding a distinct biological response which is fundamentally different from the one observed with conventional irradiation, offers high response rates (80-90%) in a tumour which was historically considered "radio resistant". As a part of the increased radiobiological effect can be attributed to vascular catastrophe (endothelial apoptosis triggered by high fractional dose), there is a rationale to investigate association of SBRT and agents targeting tumour angiogenesis in mRCC in upcoming clinical trials.

[The CyberKnife as a perfect tool for new therapeutic challenges in radiotherapy]

The "wholy grale" in radiotherapy is the search for a treatment as conformal as possible allowing to apply very high doses on the target while leaving healthy tissues as much as possible outside the prescription isodose. Radiotherapy is characterized by a never ending technical evolution aiming at increasing biological efficacy on the target while reducing toxicity at the level of the surrounding organs at risk. One of the by-products of this ever lasting quest to precision and dose concentration is the concept of radiotherapy in stereotactic conditions. For a long time the technique has only been available for cranial non-moving targets, as high precision and moving targets have long been considered antinomic for technical reasons. The clinical need to apply these same concepts for extra-cranial locations, potentially suitable to move during the irradiations, has been a booster to develop informatics and robotics. The result of these technical developments is the CyberKnife. We intend to present this technique and highlight the experience of more than two years of clinical use in the department of radiotherapy in the University Hospital of Liège. The various indications of stereotactic radiotherapy with CyberKnife will be reviewed.

13C-sodium acetate breath test for evaluation of gastric emptying times in dogs with gastric dilatation-volvulus

OBJECTIVE

The aim of the study was to assess solid phase gastric emptying via non-invasive 13C-sodium acetate breath test in large breed dogs with or without gastric dilatation-volvulus (GDV).

MATERIAL AND METHODS

Dogs were recruited into one of the following groups: group 1 = healthy large breed dogs with no history of GDV, group 2 = dogs that underwent elective abdominal surgery for reasons unrelated to the gastrointestinal tract, and group 3 = dogs that underwent laparotomy and gastropexy to correct GDV. The dogs were fed a test meal containing 100 mg 13C-sodium acetate (for group 2 and 3, this was < 48 hours post-operatively). Breath samples were obtained at baseline and every 30 minutes for 3 hours, then every hour for a total of 7 hours. 12CO2/13CO2 ratio was measured for each breath sample via non-dispersive infrared spectroscopy and 25%, 50% and 75% gastric emptying times were calculated and compared between groups.

RESULTS

Gastric emptying times were significantly prolonged in dogs undergoing surgery (group 2) compared to group 1 and 3. Also, gastric emptying times of dogs with GDV were significantly prolonged compared to controls, but not to the same extent as dogs in group 2.

CONCLUSION AND CLINICAL SIGNIFICANCE

There was a significant effect of abdominal surgery on gastric emptying times. Surprisingly, dogs after GDV surgery and gastropexy had shorter gastric emptying times than dogs undergoing laparotomy for reasons other than GDV, but still prolonged compared to healthy controls. The reason for these differences requires further study.