PURPOSE:Overageing and climate change cause a need for making processes in the operating room wing (OR wing) more efficient. While many promising technologies are available today, traditional OR wings are not designed for seamlessly integrating these aids. To overcome this discrepancy, we present and motivate multiple ideas on how to transform current architectural design strategies.METHODS:The presented concepts originate from expert discussions and studies of the available literature, but also from experiences made in the course of daily care delivery. Additionally, a comprehensive evaluation of current and historic OR theatre designs and the problems which are encountered herein has been conducted.RESULTS:We present three innovative concepts regarding the restructuring of traditional OR wing layouts. To achieve better process optimization, hygiene, and energy efficiency, we propose to divide the OR wing into separate "patient", "procedure" and "staff" zones. For better flexibility regarding perioperative needs and technology integration, we propose to use a hexagon shape combined with reconfigurable walls for designing operating rooms.CONCLUSION:The concepts presented herein provide a solid foundation for further considerations regarding perioperative process optimization and seamless integration of technology into modern OR wing facilities. We aim at expanding on these results to develop a comprehensive vision for the OR wing of the future.

PURPOSE:Today's hospitals are designed as collections of individual departments, with limited communication and collaboration between medical sub-specialties. Patients are constantly being moved between different places, which is detrimental for patient experience, overall efficiency and capacity. Instead, we argue that care should be brought to the patient, not vice versa, and thus propose a novel hospital architecture concept that we refer to as Patient Hub. It envisions a truly patient-centered, department-less facility, in which all critical functions occur in the same building and on the same floor.METHODS:To demonstrate the feasibility and benefits of our concept, we selected an exemplary patient scenario and used 3D software to simulate resulting workflows for both the Patient Hub and a traditional hospital based on a generic hospital template by Kaiser-Permanente.RESULTS:According to our workflow simulations, the Patient Hub model effectively eliminates waiting and transfer times, drastically simplifies wayfinding, reduces overall traveling distances by 54%, reduces elevator runs by 78% and improves access to quality views from 67 to 100% for patient rooms, from 0 to 100% for exam rooms and from 0 to 38% for corridors. In addition, the interaction of related medical fields is improved while maintaining the quality of care and the relationship between patients and caregivers.CONCLUSION:With the Patient Hub concept, we aim at rethinking traditional hospital layouts. We were able to demonstrate, alas on a proof-of-concept basis, that it is indeed feasible to place the patient at the very center of operations, while increasing overall efficiency and capacity at the same time and maintaining the quality of care.

Medical ionizing radiation procedures and especially medical imaging are a non negligible source of exposure to patients. Whereas the biological effects of high absorbed doses are relatively well known, the effects of low absorbed doses are still debated. This work presents the development of a computer platform called Image and Radiation Dose BioBank (IRDBB) to manage research data produced in the context of the MEDIRAD project, a European project focusing on research on low doses in the context of medical procedures. More precisely, the paper describes a semantic database linking dosimetric data (such as absorbed doses to organs) to the images corresponding to X-rays exposure (such as CT images) or scintigraphic images (such as SPECT or PET images) that allow measuring the distribution of a radiopharmaceutical. The main contributions of this work are: 1) the implementation of the semantic database of the IRDBB system and 2) an ontology called OntoMEDIRAD covering the domain of discourse involved in MEDIRAD research data, especially many concepts from the DICOM standard modelled according to a realist approach.

PURPOSE:The parcellation of the thalamus into different nuclei involved in different corticothalamocortical loops reflects its functional diversity. The connections between the mediodorsal nucleus and the prefrontal cortex play a major role in cognition, particularly in the rapid processing of behaviorally relevant information. The thalamus is the brain region with the highest density in α4β2 nicotinic acetylcholine receptors, the main human nicotinic acetylcholine receptor subtype. The aim of this study was to investigate the possible role of the nicotinic cholinergic system in the thalamo-cortical loops measuring receptor density in different subregions of the thalamus, based on their cortical connectivity.PROCEDURES:We studied α4β2 nicotinic acetylcholine receptors using positron emission tomography and [18F]Fluoro-A-85380, a radiotracer specific for this receptor subtype, in 36 non-smoking male subjects, including 12 healthy controls and 24 patients with epilepsy. [18F]Fluoro-A-85380 ratio index of binding potential was compared by a repeated measures general linear model, including the thalamic subregions and the brain hemisphere as within-subject factor and clinical groups as between-subject factor.RESULTS:The "prefrontal" thalamus, the subregion including the mediodorsal nucleus, had a significantly higher nicotinic acetylcholine receptor density than all other thalamic subregions. These findings were confirmed when analyzing solely the 12 healthy controls.CONCLUSIONS:This particular neurochemical organization of the thalamus supports a major role of the cholinergic system in the loops between the thalamus and the prefrontal cortex. The highest nicotinic acetylcholine receptor density in the « higher-order thalamus » could partly explain the beneficial effect of acute nicotine on attentional and executive functions and possibly the pathophysiology of some neuropsychiatric disorders.

In the last decade, the research community focused on defining reliable biomarkers for the early detection of the pathological hallmarks of Alzheimer’s Disease (AD). In 2017, the Geneva AD Biomarker Roadmap Initiative adapted the framework for the systematic validation of oncological diagnostic biomarkers to AD, with the aim to accelerate their development and implementation in clinical practice. With this work we assess the maturity of [18F]flortaucipir and we define the research priorities.

In the last decade, the research community has focused on defining reliable biomarkers for the early detection of the pathological hallmarks of Alzheimer’s Disease (AD). In 2017, the Geneva AD Biomarker Roadmap Initiative adapted the framework for the systematic validation of oncological diagnostic biomarkers (Pepe et al., 2001) to AD, with the aim to accelerate their development and implementation in clinical practice (Frisoni et al., 2017). With this work we assess the maturity of tau biomarkers and we define the research priorities.

PURPOSE:The MEDIRAD project is about the effects of low radiation dose in the context of medical procedures. The goal of the work is to develop an informatics service that will provide the researchers of the MEDIRAD project with a platform to share acquired images, along with the associated dosimetric data pertaining to the radiation resulting from the procedure.METHODS:The authors designed a system architecture to manage image data and dosimetric data in an integrated way. DICOM and non-DICOM data are stored in separated repositories, and the link between the two is provided through a semantic database, i.e., a database whose information schema in aligned with an ontology.RESULTS:The system currently supports CT, PET, SPECT, and NM images as well as dose reports. Currently, two workflows for non-DICOM data generated from dosimetric calculations have been taken into account, one concerning Monte Carlo-based calculation of organ doses in Chest CT, and the other estimation of doses in nontarget organs in 131I targeted radionuclide therapy of the thyroid.CONCLUSION:The system is currently deployed, thus providing access to image and related dosimetric data to all MEDIRAD users. The software was designed in such a way that it can be reused to support similar needs in other projects.

Selective positron emission tomography (PET) tracers to target neurofibrillary tangles of the second generation have indicated to overcome some of the methodological issues observed with the tau‐tracers of the first generation. How these second‐generation tau tracers may be better suitable for clinical practice was assessed in the context of the Geneva Biomarker Roadmap Initiative during and prior to a two‐day workshop (Geneva, November 2019).

OBJECTIVE:Automated voxel-based analysis methods are used to detect cortical hypometabolism typical of Alzheimer's Disease (AD) on FDG-PET brain scans. We compared the accuracy of two clinically validated tools for their ability to identify those MCI subjects progressing to AD at followup, to evaluate the impact of the analysis method on FDG-PET diagnostic performance.METHODS:SPMGrid and BRASS (Hermes Medical Solutions, Stockholm, Sweden) were tested on 131 MCI and elderly healthy controls from the EADC PET dataset. The concordance between the tools was tested by correlating the quantitative parameters (z- and t-values), calculated by the two software tools, and by measuring the topographical overlap of the abnormal regions (Dice score). Three independent expert readers blindly assigned a diagnosis based on the two map sets. We used conversion to AD dementia as the gold standard.RESULTS:The t-map and z-map calculated with SPMGrid and BRASS, respectively, showed a good correlation (R > .50) for the majority of individual cases (128/131) and for the majority of selected regions of interest (ROIs) (98/116). The overlap of the hypometabolic patterns from the two tools was, however, poor (Dice score .36). The diagnostic performance was comparable, with BRASS showing significantly higher sensitivity (.82 versus .59) and SPMGrid showing higher specificity (.87 versus .52).CONCLUSION:Despite similar diagnostic performance in predicting conversion to AD in MCI subjects, the two tools showed significant differences, and the maps provided by the tools showed limited overlap. These results underline the urgency for standardization across FDG-PET analysis methods for their use in clinical practice.

Radiomics, artificial intelligence, and deep learning figure amongst recent buzzwords in current medical imaging research and technological development. Analysis of medical big data in assessment and follow-up of personalised treatments has also become a major research topic in the area of precision medicine. In this review, current research trends in radiomics are analysed, from handcrafted radiomics feature extraction and statistical analysis to deep learning. Radiomics algorithms now include genomics and immunomics data to improve patient stratification and prediction of treatment response. Several applications have already shown conclusive results demonstrating the potential of including other “omics” data to existing imaging features. We also discuss further challenges of data harmonisation and management infrastructure to shed a light on the much-needed integration of radiomics and all other “omics” into clinical workflows. In particular, we point to the emerging paradigm shift in the implementation of big data infrastructures to facilitate databanks growth, data extraction and the development of expert software tools. Secured access, sharing, and integration of all health data, called “holomics”, will accelerate the revolution of personalised medicine and oncology as well as expand the role of imaging specialists.

Nicotinic acetylcholine receptors (nAChRs) are widely distributed in the human brain and play an important role in the neuromodulation of brain networks implicated in attentional processes. Previous work in humans showed that heteromeric α4β2 nAChRs are abundant in the cingulo-insular network underlying attentional control. It has been proposed that cholinergic neuromodulation by α4β2 nAChRs is involved in attentional control during demanding tasks, when additional resources are needed to minimize interference from task-irrelevant stimuli and focus on task-relevant stimuli. Here we investigate the link between the availability of α4β2 nAChRs in the cingulo-insular network and behavioral measures of interference control using two versions of the Stroop paradigm, a task known to recruit cingulo-insular areas. We used a previously published PET dataset acquired in 24 non-smoking male subjects in the context of a larger study which investigated the brain distribution of nAChRs in two clinical groups using 2-[(18)F]F-A-85380 PET. We found that higher availability of α4β2 nAChRs in the dorsal anterior cingulate cortex (ACC) predicted better interference control independently of group and age. In line with animal models, our results support the view that the availability of α4β2 nAChRs in the dorsal ACC is linked with more efficient attentional control.

To evaluate the diagnostic performance of a whole-body 18F-choline (FCH) hybrid PET/MRI for prostate cancer patients at biochemical relapse after radical prostatectomy (RP) compared to pelvic multiparametric MRI (mpMRI), one of the standard imaging modality for this patient population. From 2010 to 2016, 58 whole-body FCH PET/MRI studies with mpMRI acquisitions were performed in 53 prostate cancer patients relapsing after curative RP. Median PSA and PSA doubling time (PSA DT) at PET study were 1.5 ng/ml and 6.5 months, respectively. The overall positivity rate of FCH PET/MRI was 58.6% (n = 34), dropping to 44% in patients with a PSA ≤ 2 ng/ml (n = 36). Median PSA values in positive and negative PET/MRI studies were 2.2 ng/ml and 0.8 ng/ml, respectively, with no differences in PSA DT (6.5 vs. 6.6 months). A PSA value ≥ 1.5 ng/ml was a significant predictor of positivity on PET/MRI studies. Compared to PET, mpMRI identified more local relapses (17 vs. 14, p = 0.453) while PET outperformed whole-body Dixon MRI for regional (16 vs. 9, p = 0.016) and distant (12 vs. 6, p = 0.031) metastases. Compared to pelvic mpMRI, the treatment approach turned out to be influenced more frequently using whole-body FCH hybrid PET/MRI studies (58.6% vs. 38%). In prostate cancer patients with biochemical recurrence after RP, whole-body FCH PET/MRI achieved a higher detection rate of nodal/distant metastases compared to pelvic mpMRI alone, increasing the change of treatment strategy by more than 20%.

Positron emission tomography (PET) has a long history in the assessment of brain physiology and pathology; however, its initial use was limited to more academic and scientific settings. This changed radically with the clinical introduction of PET–computed tomography (PET-CT). PET-CT has become an integral part of the radiological armamentarium, especially in the assessment of patients with oncological or cardiovascular disorders. It has until now not found a clear role in neuroradiology. Indeed, magnetic resonance techniques have proven superior for the investigation of brain tumors and inflammatory diseases. However, some newer applications are emerging that can re-center PET-CT clearly in the neuroradiological world such as the investigation of vascular diseases.

We analyzed education, as a proxy of cognitive reserve, and the cholinergic pathway in Alzheimer's disease (AD), to test the hypothesis that education might modulate the relationship between clinical symptoms and metabolic and structural changes in AD. We included 84 subjects and compared between diagnostic groups and different educational levels the glucose metabolism of basal forebrain (BFM) and volume of the basal forebrain, the major cholinergic structure, and hippocampus (HM) (and hippocampal volume), a relevant projection site for the basal forebrain. Correlations with the global cognitive status and education in the whole sample were also performed. Patients with AD dementia showed reduced basal forebrain volume, hippocampal volume, and HM compared with controls. In the whole group, the global cognitive status was positively correlated with BFM and HM. Among high-educated subjects, mild cognitive impairment showed higher BFM and HM in comparison to other diagnostic groups. Our results suggest that in mild cognitive impairment subjects with a higher educational level, cholinergic activity is upregulated and this appears to have a compensatory effect, which may be lost in later symptomatic stages.

In great part due to recent advances in medical technology, ischemic cerebral stroke has become an increasingly treatable condition, which requires urgent measures and which rely on pharmacological and/or interventional measures. Due to its high prevalence, preventive measures should also be undertaken, and this is a situation where the use of advanced neuroimaging techniques could be helpful in certain underlying diseases. What is proposed here is to discuss how modern neuroimaging techniques (advanced magnetic resonance (MR) techniques and/or nuclear medicine techniques such as positron emission tomography (PET)) could help in situations that would otherwise lead to a stroke. Since both primary and secondary prevention measures are often required, we see that the techniques can be helpful in both situations. The diseases that cause stroke that can be investigated are, among others, carotid stenosis; transient ischemic attacks (TIAs) may also be followed by a major stroke if nothing is undertaken. It has been established that carotid stenosis is to be treated in the presence of a significant lesion that has neurological symptoms. The question of how to deal with these patients often arises when the relationship between the stenosis and symptoms is not significant or the symptomatology unclear. In such situations, either PET and/or fat-saturated T1 images of the carotids can help to demonstrate the embolic nature of the plaque. We have seen that carotid plaque vulnerability, which can cause embolism, can be associated with plaque inflammation (seen on PET) or plaque haemorrhage (seen on MR images). Also, while PET and MRI will demonstrate different stages of plaque vulnerability, they can both help to demonstrate vascular lesions that are at risk of causing significant ischemic events. Diffusion-weighted imaging (DWI) has shown that some TIAs may indeed be ischemic brain lesions with a transient symptomatology. The early use of DWI can thus help treat these patients more acutely. Based on this, we have seen that newer imaging techniques can provide additional knowledge about conditions that may lead to stroke and be treated. This should have a major impact on patient outcomes and ultimately on healthcare costs related to this condition.

The TT-PET collaboration is developing a small animal TOF-PET scanner based on silicon detectors featuring 30 ps RMS time resolution and intended to be inserted in an existing MRI scanner. The TT-PET scanner makes use of a stack of layers of high-Z photon-converter and 100 μ m thick silicon sensors, to achieve a scanner with 0.5 × 0.5 × 0.2 mm^3 granularity, with precise depth-of-interaction measurement. In this paper we present the results of the Monte Carlo studies for the expected data rate, time resolution on the TOF measurements, spatial resolution and image reconstruction with and without the use of the timing information. Most of the studies have been performed according to the international standards used to assess the performance of small-animal PET system.

Vessel Plus is an open acccess journal, which publishes articles related to vascular diseases, including acute respiratory distress syndrome, aneurysm, atherosclerosis, hypertension, stroke, peripheral vascular or pulmonary vascular diseases, etc.

Sparse information is available on the role of cardiac viability imaging in elderly patients. We aimed at evaluating the prognostic value of FDG-PET/CT in elderly patients with stable coronary artery disease (CAD) and reduced left ventricular ejection fraction (rLVEF) before revascularisation. Elderly patients (> 65 years old, mean 74 ± 7 years old) with CAD and rLVEF were followed after cardiac FDG-PET/CT and stratified according to presence/absence of viable myocardium and subsequent revascularisation. Fatal events of any cause as well as hospitalisations related to acute cardiac conditions were reported as clinical end-points. Predictors of fatal events in patients with viable myocardium (> 1 myocardium segment/20) were analysed. A total of 89 patients were followed (64 viable myocardia; 37 and 27 patients with and without subsequent revascularisation, respectively). The change in LVEF during follow-up (2.1 ± 1.6 years) was 3.8 ± 6.6% (P = 0.013) and − 0.75 ± 2.6% (P = 0.170) in patients with and without revascularisation, respectively. Log-rank (P = 0.037) and multivariate analysis (Wald: 6.305, P = 0.012) showed viable myocardium to be significantly associated with fatal events if not revascularised. Elderly patients with viable myocardium might potentially benefit from revascularisation procedures as improved left ventricular ejection fraction and survival were observed in our retrospective study as compared to patients in whom a revascularisation procedure was denied. Viable myocardium as detected by cardiac FDG PET/CT was associated with better clinical outcomes in elderly patients when revascularised.