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Abstract Background Continuously monitored external dose-rate signals from remote dose-rate meters (DRMs) were analyzed to determine the effective half-life (Teff) of 131I in differentiated thyroid cancer (DTC) patients. The aim is to gain novel understanding of the excretion of radioactive iodine (RAI) in DTC patients and to demonstrate that a remote DRM system can be reliably used for real-time monitoring of external dose-rates of DTC patients. Methods 110 DTC patients who received postoperative RAI therapy between September 2018 and February 2023 in Turku University Hospital were studied retrospectively. The external dose-rates of the patients were continuously monitored during their hospitalization with a remote DRM fixed in the ceiling of the isolation room. Generalized linear mixed model (GLMM) was used to analyse the association between logarithmical Teff and patient characteristics. Results The median Teff for all patients was 12.60 h (Q1: 10.35; Q3: 14.75 h). Longer Teffs were associated with higher BMI (p = 0.004), lower GFR (p

Abstract Background We evaluated the effects of acquisition time, energy window width, and matrix size on the image quality, quantitation, and diagnostic performance of whole-body 99mTc-HMDP SPECT/CT in the primary metastasis staging of prostate cancer. Methods Thirty prostate cancer patients underwent 99mTc-HMDP SPECT/CT from the top of the head to the mid-thigh using a Discovery NM/CT 670 CZT system with list-mode acquisition, 50-min acquisition time, 15% energy window width, and 128 × 128 matrix size. The acquired list-mode data were resampled to produce data sets with shorter acquisition times of 41, 38, 32, 26, 20, and 16 min, narrower energy windows of 10, 8, 6, and 4%, and a larger matrix size of 256 × 256. Images were qualitatively evaluated by three experienced nuclear medicine physicians and quantitatively evaluated by noise, lesion contrast and SUV measurements. Diagnostic performance was evaluated from the readings of two experienced nuclear medicine physicians in terms of patient-, region-, and lesion-level sensitivity and specificity. Results The originally acquired images had the best qualitative image quality and lowest noise. However, the acquisition time could be reduced to 38 min, the energy window narrowed to 8%, and the matrix size increased to 256 × 256 with still acceptable qualitative image quality. Lesion contrast and SUVs were not affected by changes in acquisition parameters. Acquisition time reduction had no effect on the diagnostic performance, as sensitivity, specificity, accuracy, and area under the receiver-operating characteristic curve were not significantly different between the 50-min and reduced acquisition time images. The average patient-level sensitivities of the two readers were 88, 92, 100, and 96% for the 50-, 32-, 26-, and 16-min images, respectively, and the corresponding specificities were 78, 84, 84, and 78%. The average region-level sensitivities of the two readers were 55, 58, 59, and 56% for the 50-, 32-, 26-, and 16-min images, respectively, and the corresponding specificities were 95, 98, 96, and 95%. The number of equivocal lesions tended to increase as the acquisition time decreased. Conclusion Whole-body 99mTc-HMDP SPECT/CT can be acquired using a general-purpose CZT system in less than 20 min without any loss in diagnostic performance in metastasis staging of high-risk prostate cancer patients.

Digital transformation compels companies to seek new strategies and business models, allowing firms to find new ways to create and capture value. APIs have been widely used in improving internal processes and have been opened up recently to third-party developers to enable innovations in digital ecosystems. However, few studies have documented success stories of value generation through employing public APIs and thus enabling new, API-driven business models. This single case study examined the digital transformation in one of the leading organizations of the travel industry, Amadeus Corporation. Publicly available documents and other gray literature were used as data for content analysis. The results show how Amadeus has transformed its business model into an API-driven business model. This study contributes to the literature on API-driven business models by demonstrating the implication of APIs as a strategic tool in value co-creation. We identified six different values that were generated by exposing digital assets to API consumers through the API-driven business models of self-service platforms: commercialization, ecosystem, big data, market and marketplace, entrepreneurship, and R&D.

Abstract Background Development of vascular calcification is accelerated in patients with end-stage renal disease. In addition to traditional risk factors of cardiovascular disease (CVD) abnormal bone and mineral metabolism together with many other factors contribute to the excess cardiovascular burden in patients on dialysis. Aortic calcification score and coronary calcification score are predictive of CVD and mortality. The aim of this study was to evaluate the possible relationship between arterial calcification and bone metabolism. Methods Thirty two patients on dialysis were included. All patients underwent a bone biopsy to assess bone histomorphometry and a 18F-NaF PET scan. Fluoride activity was measured in the lumbar spine (L1 – L4) and at the anterior iliac crest. Arterial calcification scores were assessed by computerized tomography for quantification of coronary artery calcification score and lateral lumbar radiography for aortic calcification score. Results This study group showed high prevalence of arterial calcification and 59% had verified CVD. Both CAC and AAC were significantly higher in patients with verified CVD. Only 22% had low turnover bone disease. There was a weak association between fluoride activity, which reflects bone turnover, measured in the lumbar spine, and CAC and between PTH and CAC. There was also a weak association between erosion surfaces and AAC. No significant association was found between calcification score and any other parameter measured. Conclusions The results in this study highlight the complexity, when evaluating the link between bone remodeling and vascular calcification in patients with multiple comorbidities and extensive atherosclerosis. Several studies suggest an impact of bone turnover on development of arterial calcification and there is some evidence of reduced progression of vascular calcification with improvement in bone status. The present study indicates an association between vascular calcification and bone turnover, even though many parameters of bone turnover failed to show significance. In the presence of multiple other factors contributing to the development of calcification, the impact of bone remodeling might be diminished. Trial registration The study is registered in ClinicalTrials.gov protocol registration and result system, ID is NCT02967042 . Date of registration is 17/11/2016.

Abstract Introduction Subtype classification method is essential when considering adrenalectomy as a possible treatment for primary aldosteronism. We aimed to retrospectively evaluate surgical outcomes of primary aldosteronism in patients who had undergone 11C‐metomidate positron emission tomography (11C‐MTO‐PET) for subtype classification. Methods Postoperative clinical and biochemical cure and histopathological diagnosis from biobank samples were retrospectively evaluated in 44 patients who had all undergone preoperative 11C‐MTO‐PET with or without adrenal venous sampling (AVS). We compared those operated based on 11C‐MTO‐PET alone and those with concordant or discordant lateralization in 11C‐MTO‐PET and AVS studies according to postoperative immunohistochemical findings and biochemical and clinical cure. Results Adrenalectomy side was based on 11C‐MTO‐PET alone in 14 cases and on AVS in 30 cases of whom 42 achieved complete and two partial biochemical cures. Among those who underwent AVS and were operated according to it, the two lateralization methods were concordant in 22 cases and discordant in 8 cases. Similar immunohistochemical profiles and cure rates were seen after 11C‐MTO‐PET alone or AVS‐based operations. Respectively, those with concordant or discordant 11C‐MTO‐PET and AVS lateralization did not differ in surgical outcome. Together, we found errors of lateralization diagnostics with 11C‐MTO‐PET in 18% and with AVS in 3% among those eligible for adrenal surgery. Conclusions Outcomes of adrenalectomy based on clinically significant lateralization in 11C‐MTO‐PET alone correspond to those based on 11C‐MTO‐PET with concordant AVS lateralization. However, our results suggest that diagnosis of unilateral PA should be performed with caution with 11C‐MTO‐PET in case of discordant lateralization studies.

Background and purpose: As a synthetic bone void filler, bioactive glasses (BGs) may enhance angiogenesis and osteogenesis. In this randomized trial, we compared the clinical efficacy of BG granules and standard bone grafts in patients undergoing surgery for benign bone tumors. Patients and methods: 49 recruited patients were randomized to receive BG granules or undergo conventional bone grafting to fill defects following tumor removal. As the standard of care, small-sized defects were filled with autologous graft, and large-sized defects were filled with allogeneic graft. The primary endpoint was treatment success at 1 year, defined by no reoperation, no tumor recurrence, and no device-related adverse events. Secondary endpoints included patient-reported outcomes (Rand-36 and pain scores) and quantitative assessment of blood flow and metabolic activity by means of 18F-fluoride PET/CT imaging. As an off-trial group, 15 children and adolescents (age < 18 years) underwent tumor removal and BG-filling, without randomization. Results: At 1-year, 21 of 25 BG-treated patients (risk estimate 0.84, 95% confidence interval [CI] 0.70–0.98) and 20 of 24 patients in the standard of care group (0.83, CI 0.68–0.98) met the criteria for treatment success. The groups had similar Rand-36 scores. In patients with small defects, BG filling was associated with shorter operative time and less postoperative pain at 1 month. In patients with large defects, blood flow was similar, but BG-filled defects showed higher metabolic activity than allograft-filled defects at 1-year. The survey of the postoperative period ≥10 years revealed no BG-related adverse events. Interpretation: BG granules had similar overall rates of treatment success compared with autografts and allografts, but large-scale trials are needed for the confirmation of clinical equivalence. The extended metabolic activity confirms the expected cellular responses of osseointegrated BG granules.

Abstract Rationale Evaluation of the feasibility of [18F]EF5-PET/CT scan in identifying hypoxic lesions in ovarian tumors in prospective clinical setting. Methods Fifteen patients with a suspected malignant ovarian tumor were scanned with [18F]EF5 and [18F]FDG-PET/CT preoperatively. The distribution of [18F]EF5-uptake, total intraabdominal metabolic tumor volume (TMTV), and hypoxic subvolume (HSV) were assessed. Results [18F]EF5-PET/CT suggested hypoxia in 47% (7/15) patients. The median HSV was 87 cm3 (31% of TMTV). The [18F]EF5-uptake was detected in primary tumors and in four patients also in intra-abdominal metastases. The [18F]EF5-uptake in cancer tissue was low compared to physiological excretory pathways, complicating the interpretation of PET/CT images. Conclusions [18F]EF5-PET/CT is not feasible in ovarian cancer imaging in clinical setting due to physiological intra-abdominal [18F]EF5-accumulation. However, it may be useful when used complementarily to FDG-PET/CT.

Abstract Background Epithelial ovarian cancer (EOC) typically spreads intra-abdominally, but preoperative evaluation with FDG PET/CT often reveals metabolically active supradiaphragmatic lymph nodes (sdLNs). Their clinical significance and behavior during treatment has not been established. Methods EOC patients with PET positive sdLNs at diagnosis were prospectively followed with PET/CT after primary chemotherapy and at the first recurrence. In each patient, 2 most active LNs in 5 different supradiaphramatic regions were evaluated and the size and changes in FDG uptake (SUVmax) were recorded. The patients´ overall response to primary treatment was defined with RECIST criteria. The behavior of sdLNs during chemotherapy were compared in treatment responders and non-responders. Recurrence patterns were monitored. Results Forty-one patients with 127 PET/CT scans were systematically evaluated. In pretreatment scan, 76% (31/41) of patients had FDG-avid sdLNs in multiple anatomical sites. Only a minority (22/136) of the sdLNs were enlarged in size, but their histopathologic confirmation by biopsy was not possible. Only 6/41 patients had FDG-avid sdLNs in a single surgically approachable site. The sdLNs became inactive during primary chemotherapy more often in the RECIST responders compared to the non-responders (HR 1.46 (95%CI: 1.09–1.96), p = 0.002). The size and SUVmax values did not predict treatment outcome. In 50% of the responders the same sdLNs reactivated when recurrence occurred. Persistent post-treatment metabolic activity did not predict earlier disease relapse (p = 0.59). Conclusion The behavior of metabolically active sdLNs during chemotherapy supports their metastatic nature. Due to their distribution to multiple regions, the benefit of removal of reachable sdLNS seems unlikely. Trial registration NCT, NCT01276574. Registered 1 September 2010.

Objective: To evaluate possible differences between brain dopamine transporter (DAT) binding in a group of symptomatic parkinsonism patients without dopaminergic degeneration and healthy individuals. Background: Dopaminergic neuroimaging studies of Parkinson’s disease (PD) have often used control groups formed from symptomatic patients with apparently normal striatal dopamine function. We sought to investigate whether symptomatic patients can be used to represent dopaminergically normal healthy controls. Methods: Forty healthy elderly individuals were scanned with DAT [123I]FP-CIT SPECT and compared to 69 age- and sex-matched symptomatic patients with nondegenerative conditions (including essential tremor, drug-induced parkinsonism and vascular parkinsonism). An automated region-of-interest based analysis of the caudate nucleus and the anterior/posterior putamen was performed. Specific binding ratios (SBR = [ROI-occ]/occ) were compared between the groups. Results: DAT binding in symptomatic patients was 8.6% higher in the posterior putamen than in healthy controls (p = 0.03). Binding correlated negatively with age in both groups but not with motor symptom severity, cognitive function or depression ratings. Conclusions: Putaminal DAT binding, as measured with [123I]FP-CIT SPECT, was higher in symptomatic controls than in healthy individuals. The reason for the difference is unclear but can include selection bias when DAT binding is used to aid clinical diagnosis and possible self-selection bias in healthy volunteerism. This effect should be taken into consideration when designing and interpreting neuroimaging trials investigating the dopamine system with [123I]FP-CIT SPECT.

Abstract Background Despite recent technological advances allowing for quantitative single-photon emission computed tomography (SPECT), quantitative SPECT has not been widely used in the clinical practice. The aim of this study is to evaluate the feasibility of quantitative SPECT for measuring metastatic bone uptake in breast and prostate cancer by comparing standard uptake values (SUVs) measured with 99mTc-HDP SPECT/CT and 18F-NaF PET/CT. Methods Twenty-six breast and 27 prostate cancer patients at high risk of bone metastases underwent both 99mTc-HDP SPECT/CT and 18F-NaF PET/CT within 14 days of each other. The SPECT and PET data were reconstructed using ordered-subset expectation-maximization algorithms achieving quantitative images. Metastatic and benign skeletal lesions visible in both data sets were identified, and their maximum, peak, and mean SUVs (SUVmax, SUVpeak, and SUVmean) were determined. SUV ratios (SUVRs) between the lesions and adjacent normal appearing bone were also calculated. Linear regression was used to evaluate the correlations between the SUVs of SPECT and PET and Bland-Altman plots to evaluate the differences between the SUVs and SUVRs of SPECT and PET. Results A total of 231 skeletal lesions, 129 metastatic and 102 benign, were analyzed. All three SUV measures correlated very strongly between SPECT and PET (R 2 ≥ 0.80, p

The platform economy is disrupting innovation while presenting both opportunities and challenges for startups. Platforms support value creation between multiple participant groups, and this operationalization of an ecosystem’s value co-creation represents the “core interaction” of a platform. This article focuses on that core interaction and studies how startups connect producers and users in value-creating core interaction through digital platforms. The study is based on an analysis of 29 cases of platform startups interviewed at a leading European startup event. The studied startups were envisioning even millions of users and hundreds or thousands of producers co-creating value on their platforms. In such platform businesses, our results highlight the importance of attracting a large user pool, providing novel services to those users, offering a new market for producers, supporting the core interaction in various ways, and utilizing elements of the platform canvas – an adaptation of the business model canvas, which we have accommodated for platform-based business models – to accomplish these goals.

Purpose: This paper offers a literature review and explains the terminology for platform ecosystem business models. It also suggests a practical tool, the Platform Canvas, to support the implementation activities. Design/Methodology/Approach: A literature review was conducted in fall 2016 that resulted in the tentative canvas approach, which was evaluated in seven real company cases. Findings: The study identified the eight most important characteristics for a business model design of a platform ecosystem. To support the development and improvement of successful business models in a platform ecosystem, the Platform Canvas tool was created. Originality/Value: The unique result is a practical tool, the Platform Canvas that facilitates business model creation in platform ecosystems.

This conceptual paper extends the traditional view of disruptive change, which considers the effects of rivalry between an incumbent and new entrant firm, by examining the impact of disruption upon the ‘innovation ecosystem’ in its entirety – the group of organisations that collaborate in creating a holistic value proposition for the end-user. Following Adner’s “ecosystem-as-structure” perspective, we develop propositions that anticipate structural differences between incumbent and disruptive innovation ecosystems, and then review these propositions in the context of three historical, disruptive innovation cases; Bakelite (a synthetic plastic), microwave oven, and photocopier. Through these cases, we illustrate that the manner of innovation ecosystem reconfiguration is likely to depend on the design attributes of the product, as well as the type of disruption experienced. We conclude by reflecting upon contemporary cases of disruption enabled through digital technologies, and proposing a framework that can guide future research.

Purpose: The paper provides a comprehensive and up-to-date literature review of customer value concepts and distinguishes complex customer value from the various perspectives. It structures the themes and dimensions between the various approaches along the customer value main lines in the literature. Design/methodology/approach: The paper reviews current literature and illustrates different types of value representations through a case example. Findings: Based on a comprehensive literature review, a framework how to scholars can structure customer value constructs is presented. Originality/value: In business and management research a conceptual confusion prevails and this paper attempts to clarify different types of customer value to provide a better resolution tool for scholars.

Commonly shared conceptualizations of resources are scant in academic management research which strikes as somewhat peculiar since resources and their allocation thereof have long been recognised to be at the heart of the competitive advantage and performance of a firm. The research literature considering resources as basis for competitive advantages has further faced contemporary criticism for the vagueness of the fundamental definition of the resource concept. Therefore, this paper empirically studies the representation of resource concept in academic management research literature. The paper reports results on the state of conceptualisations of organisations’ resources found in two distinct sources of research literature, namely ScienceDirect’s database and ISI’s top management journals, resulting in two data sets of a total of 457 articles. The findings illustrate the two-dimensional conceptual farrago in the conceptualisations; on the definitions of the resource concept itself and on the internal structure and the level of analysis when the concept is considered. In addition, the paper sheds light on the temporal evolution of the discourse explicitly considering resources. Finally, the paper considers several remedies for these deficiencies in order both to aid future theory development in management studies and to help increase the practical impact of the research in assisting managerial decision-making.

The concept of the business model has been designed for aiding exploitation of the business potential of an innovation. This exploitation inevitably involves new activities in the organisational context and generates a need to select and arrange the resources of the firm in these new activities. A business model encompasses those resources that a firm has access to and aids in a firm’s effort to create a superior ‘innovation capability’. Selecting and arranging resources to utilise innovations requires resource allocation decisions on multiple fronts as well as poses significant challenges for management of innovations. Although current business model conceptualisations elucidate resources, explicit considerations for the composition and the structures of the resource compositions have remained ambiguous. As a result, current business model conceptualisations fail in their core purpose in assisting the decision-making that must consider the resource allocation in exploiting business opportunities. This paper contributes to the existing discussion regarding the representation of resources as components in the business model concept. The categorized list of resources in business models is validated empirically, using two samples of managers in different positions in several industries. The results indicate that most of the theoretically derived resource items have their equivalents in the business language and concepts used by managers. Thus, the categorisation of the resource components enables further development of the business model concept as well as improves daily communication between managers and their subordinates. Future research could be targeted on linking these components of a business model with each other in order to gain a model to assess the performance of different business model configurations. Furthermore, different applications for the developed resource configuration may be envisioned.

Despite the growing attention innovation ecosystems have received from scholars and practitioners, rather little is known about the crucial birth and expansion phases that these ecosystems experience. Through a single case in the complex product system (CoPS) environment, this paper investigates the development of an innovation ecosystem between 1980 and 2007. The findings demonstrate that the ecosystem’s birth phase includes sub-phases, namely, invention and start-up, where the ecosystem is reconfigured to find the appropriate form and the proper actors to satisfy the first customer’s requirements. Moreover, the duration of the expansion phase is found to be remarkably long, suggesting that within the CoPS setting, expansion may also include two or more sub-phases.