Philips Medical Systems Research Articles

Emotional Durability Design Nine—A Tool for Product Longevity

How can we develop products that consumers want to use for longer? The lifetime of electrical products is an ongoing concern in discussions about the circular economy. It is an issue that begins at an industry level, but that directly influences the way in which consumers use and discard products. Through a series of workshops and knowledge exchange sessions with Philips Lighting, this paper identifies which design factors influence a consumer’s tendency to retain their products for longer. These were distilled into a guiding framework for new product developers—The Emotional Durability Design Nine—consisting of nine themes: relationships, narratives, identity, imagination, conversations, consciousness, integrity, materiality, and evolvability. These nine themes are complemented by 38 strategies that help in the development of more emotionally engaging product experiences. We propose that the framework can be applied at multiple points during the new product development process to increase the likelihood that ‘emotion building’ features are integrated into an end product.

Procedure and step-based analysis of the occupational radiation dose during endovascular aneurysm repair in the hybrid operating room

ObjectiveThis study measured the cumulative occupational X-ray radiation dose received by support staff during endovascular aortic procedures and during additional intraoperative steps in the hybrid operating room. MethodsRadiation dose measurements were performed during interventions on 65 patients receiving 90 stent grafts during endovascular aneurysm repair (EVAR), bifurcated EVAR, thoracic EVAR, iliac branched device deployment, aortouni-iliac stenting, and fenestrated/branched EVAR (F/BrEVAR). X-ray imaging was acquired using the Philips Allura FD20 Clarity System (Philips Medical Systems, Best, The Netherlands). The occupational radiation dose (also referred to as the estimated effective dose, E, measured in millisieverts) was measured with the DoseAware Xtend system (Philips Medical Systems) personal dosimeters. E was reported per staff member (ESTAFF), where “staff” was a generic term for each staff member included in the study: the first operator (FO), the second operator (ESO), a virtual maximum operator (MO), and all additional supporting staff, including the sterile nurse, nonsterile nurse, anaesthesiologist, and radiation technician. The primary outcome was the median cumulative ESTAFF (or EFO, EMO, and so on), which was presented as the median cumulative dose per intervention and stratified for several within-interventional EVAR and F/BrEVAR steps or stents. The second outcome was the percentage of the absorbed E by a supporting staff member in relation to the E measured by the reference badge attached on the C-arm (ESTAFF% or EFO%, EMO%, and so on). All outcomes are presented as median with interquartile range, unless stated differently. ResultsThe occupational effective dose in millisieverts of the MO (EMO) was 0.055 (0.029-0.082) for aortouni-iliac stenting (n = 6), 0.084 (0.054-0.141) during thoracic EVAR (n = 14), 0.036 (0.026-0.068) during bifurcated EVAR (n = 38), 0.054 (0.035-0.126) during iliac branched device deployment (n = 8), and 0.345 (0.235-0.757) during F/BrEVAR (n = 24). The median EMO in millisieverts was 0.025 (0.012-0.062) per renal target vessel (TV) and 0.146 (0.07-0.315) for a nonrenal visceral TV. During all noncomplex interventions, the EMO% was 4.4% (2.7%-7.3%), with the lowest median rate at 3.5% (2.5%-5%) for EVAR. The highest median rate EMO% was found for F/BrEVAR procedures: 8.2% (5.0%-14.4%). ConclusionsWith maximum operator shielding during femoral access, relative occupational radiation risk can be minimized. However, digital subtraction angiography image acquisition, recanalization of TVs, recanalization of superior mesenteric artery or celiac artery, and recanalization of branched TVs are predictors for increased occupational radiation dose risks caused by increased radiation doses to the patient and reduced options for shielding of the operator.

Assessment of hepatic and cardiac iron overload in thalassemia patients by magnetic resonance imaging: Our experience in Alexandria University

Aim of the studyThe aim of this study was to assess the utility of MRI as a non-invasive technique for grading of the hepatic and cardiac iron overload in Thalassemia patients in a cohort of patients in Alexandria, Egypt. Patients and methodsThe study included 80 known patient with Thalassemia on repeated blood transfusion referred from internal medicine department (hematology unit) to the radiology department at Alexandria main university hospital. A 1.5-Tesla MR scanner was used (Achieva; Philips Medical Systems, the Netherlands) equipped with a standard five-element synergy cardiac coil. ResultsThe myocardial iron overload among our cases were as follow: 73 cases (91.3%) with no overload, 5 cases (6.3%) with mild overload, one case (1.3%) with moderate overload and also only one case (1.3%) with sever iron overload. The hepatic iron overload among the studied cases were as follow: 20 patients (25%) with no overload, two patients (2.5%) were upper normal overload, 9 cases (11.3%) with mild overload, 47 patients (58.8%) with moderate overload and only two patients (2.5%) with sever overload. ConclusionMost thalassemia major patients in our study, who had no regular chelation therapy, had hepatic iron overload, less frequently myocardial iron overload.

Perioperative neonatal brain injury is associated with worse school‐age neurodevelopment in children with critical congenital heart disease

To assess the impact of perioperative neonatal brain injury and brain volumes on neurodevelopment throughout school-age children with critical congenital heart disease (CHD). Thirty-four survivors of neonatal cardiac surgery (seven females, 27 males) were included. Neonatal preoperative and postoperative cerebral magnetic resonance imaging was performed and neurodevelopment was assessed at 24months (SD 0.7, n=32, using Bayley Score of Infant and Toddler Development, Child Behavior Checklist) and 6years (mean age 5y 11mo; SD 0.3, n=30, using Movement Assessment Battery for Children, Wechsler Preschool and Primary Scale of Intelligence, Child Behavior Checklist, Teacher Report Form). Brain injury, brain volumes, and cortical measures were related to outcome with adjustment for maternal educational level. Two-year cognitive score and 6-year Full-scale IQ were poorer in children with neonatal white matter injury (n=21, all p<0.05), with higher teacher-reported attention problems (p=0.03). Five of six children with involvement of the posterior limb of the internal capsule showed motor problems (p=0.03). Children with a below-average Fulll-scale IQ (<85, n=9) showed smaller volumes of basal ganglia thalami (-8%, p=0.03) and brain stem (-7%, p=0.03). Our findings provide evidence of unfavourable outcome in school-age children with critical CHD who acquire perioperative neonatal brain injury. This paper extends knowledge about neonatal brain injury and long-term outcome in congenital heart disease. Children with white matter injury show lower IQ and more attention problems at school age. Injury of the posterior limb of the internal capsule increases the risk of motor problems. This study provides evidence for worse outcomes in neonates acquiring brain injury around cardiac surgery.

Role of Diffusion Weighted Magnetic Resonance Imaging in Differentiation between Benign and Malignant Vertebral Body Collapse

AbstractBackground: In recent years, MRI has increasingly become the modality of choice for imaging of musculoskeletal disor-ders. Diffusion weighted MR sequences provide microscopic information to supplement the macroscopic information pro-vided by conventional sequences. It is a non invasive imaging technique which is suitable for probing the physical structure of a biologic tissue at a microscopic level and it exploits the random, translational motion of water protons in a biologic tissue, which reflects the tissue specific diffusion capacity and can be used for tissue characterization.Aim of Work: The aim of this study is to determine the value of Diffusion Weighted Imaging (DWI) in differentiation between different causes of vertebral collapse.Patients and Methods: This is a prospective study carried out in Radio-Diagnosis Department, Faculty of Medicine, Cairo University between August 2014 and February 2016 for patients diagnosed with vertebral body collapse. A total number of 35 patients (20 males and 15 females) with age range 18-74 (average 52).The MRI sequences obtained were sagittal T1WI, T2WI, STIR and axial T1WI, T2WI & DWI (± post contrast images in some patients). Bone marrow signal intensity of the collapsed vertebra was analyzed by comparing its signal intensity with the signal intensity of the intervertebral disc, fat and muscle tissue on T1-weighted images, the signal intensity of the affected veteba was also inspected on DWI then ADC values were automatically calculated using the software provided by the MR scanner manufacturer (Diffusion Calculation: Philips Medical Systems) and the ADC quantitative parameter was expressed in: 10–3mm2/s.Results: Our study included 35 patients who were diag-nosed with vertebral body collapse. Qualitative evaluation of the lesion contrast in diffusion-weighted MRI of the vertebral column has been shown to be valuable for the differentiation of lesion etiology; however, visual assessment of high signal intensity was not specific for malignancy.On the other hand the quantitative assessment by meas-uring the ADC value was able to distinguish different types of vertebral collapse.In our study, there was statistically Highly Significant (HS) difference between malignant and the following benign causes of vertebral collapse; acute fracture, chronic osteoporot-ic collapse and pyogenic spondylodiscitis. There is also statistically significant difference (S) between malignant and TB spondylodiscitis lesions according to ADC values.Conclusion: Diffusion weighted MRI can be used as a reliable tool in differentiation between different causes of vertebral body collapse. DWI could be applied as a cost effective substitute for the gadolinium enhanced scan especially in patients with contraindication for contrast administration.

Diffusion Weighted Magnetic Resonance Imaging in Diffuse and Focal Vertebral Bone Marrow Lesions Using Apparent Diffusion Coefficient (ADC) Mapping as a Quantitative Assessment Tool

AbstractBackground: Routine magnetic resonance imaging MRI is highly sensitive in detecting bone marrow alterations; however, it is of limited specificity in the evaluation of the causes of these alterations. Diffusion Weighted Imaging (DWI) is an imaging technique which probes the structure of a biologic tissue. The contrast achieved with this technique together with measurement of the apparent diffusion coefficient ADC values are useful complementary MRI tools and can be used for non-invasive tissue characterization and therefore reaching a more specific diagnosis.Aim of Work: The aim of this study is to determine the value of both qualitative and quantitative assessment of DWI in differentiation between different vertebral lesions and to determine cut off ADC value between benign and malignant lesions.Patients and Methods: This is a prospective study carried out in Radio-Diagnosis Department, Faculty of Medicine, Cairo University between August 2014 and February 2016 for patients diagnosed with or suspected to have vertebral lesion of any etiology. A total number of 40 patients (22 males and 18 females) with age range 2-88 (average 49).The MRI sequences obtained were sagittal T1WI, T2WI, STIR and axial T1WI, T2WI & DWI (± post contrast images in some patients). Bone marrow signal intensity was qualita-tively analyzed by visually comparing its signal intensity with the signal intensity of the intervertebral disc, fat and muscle tissue on T1-weighted images. Hyperintense lesions on the DWI were identified and ADC values were automatically calculated using the software provided by the MR scanner manufacturer (Diffusion Calculation: Philips Medical Systems) and the ADC quantitative parameter was expressed in: 1 0–3mm2/s.Results: Our study included 40 patients who were diag-nosed with or suspected to have vertebral lesion of any etiology. Qualitative evaluation of the lesion contrast in diffusion-weighted MRI of the vertebral column has been shown to be valuable for the differentiation of lesion etiology; however, visual assessment of high signal intensity was not specific for malignancy.On the other hand the quantitative assessment by meas-uring the ADC value was able to distinguish benign from malignant high signal intensity on DWI.In our study, infiltrated neoplastic marrow as well as hypercellular red marrow had higher ADC values than normal marrow while inflammatory lesions and hemangiomas had the highest ADC values.Conclusion: Diffusion weighted MRI is a reliable tool in characterization of different vertebral bone marrow abnormal-ities. The routine MRI protocol of spine examinations could be modified to include DWI as a cost effective substitute for the gadolinium enhanced scan especially in patients with contraindication for contrast administration.

3:18 PM Abstract No. 53 Changes in two-dimensional perfusion angiography before and after inferior vena cava filter retrieval

To investigate differences in hemodynamic flow parameters acquired in two-dimension (2D) perfusion angiography before and after inferior vena cava (IVC) filter retrieval. IVC filter retrievals at a single institution were retrospectively reviewed. Standardized breath-hold, digital subtraction angiography was performed at 2-3 frames per second before and after removal, and 2D-perfusion images were reconstructed on a dedicated workstation (Philips Allura Xper FD20, Philips Medical Systems, Best, Netherlands). Changes in the density per pixel per second within a region of interest (ROI) were used to calculate contrast arrival time, time-to-peak (TTP), wash-in-rate (WIR), area under the curve (AUC), and mean transit time (MTT). Measurements were obtained inferior, superior, and at the level of the filter. Differences in the hemodynamic parameters before and after filter removal were assessed with Mann-Whitney U analysis. A p-value of <0.05 was considered statistically significant. At the level of the filter, the TTP was significantly longer before filter removal when compared to after, with mean times of 1.28 and 0.78 seconds, respectively (p = 0.042). The MTT inferior to the filter was longer before filter removal when compared to after, with mean times of 0.8 and 0.5 seconds, respectively. The WIR inferior to the filter was longer before filter removal when compared to after, with mean of 435 and 250 HU/second, respectively. Preliminary data evaluating differences in flow parameters acquired in 2D-perfusion angiography before and after IVC filter retrieval demonstrate a significantly longer TTP when filters are in place, suggesting a functional hemodynamic delay secondary to filter presence.

A collapsed-cone based transit EPID dosimetry method

PurposeTo develop a transit-dose portal dosimetry method based on a commercial collapsed-cone algorithm. MethodsA Varian Clinac21EX (Varian Medical Systems, USA), equipped with an amorphous-silicon EPID aS1000, was used.Dose calculations were performed with the collapsed-cone algorithm of Pinnacle3 v8.0 m (Philips Medical Systems, USA). A model for the energy of 6 MV was made in Pinnacle3 and afterwards validated for clinical use.A virtual phantom with different densities was contoured and superimposed on the patient images, simulating the presence of the EPID during the treatment. Corrections for photon spectral variations were introduced using Matlab (Mathworks, USA).Transit dosimetry was verified with an anthropomorphic phantom, on which different treatment fields were simulated in locations of skull, thorax and pelvis. In addition, a prostate treatment with IMRT was administered thereon. Dose distributions were compared with gamma index. ResultsThe dose differences at the central point did not exceed 2%, except for the 20 x 20 cm2 field size centered in the skull. The model presented in this work, assumes that the dimensions of the solid water phantom, are infinite, except for the thickness.The mean values for the gamma index pass rates were 85.62% for (3%, 3 mm), 91.73% (4%, 3 mm) and 95.68% (5%, 3 mm). ConclusionsThe value of 95% for γ (5%, 3 mm) can be established as the value below which the origin of the discrepancies should be investigated. It should be considered that the proposed method is complementary and not a substitute for pre-treatment dosimetry.

Diffusion-weighted magnetic resonance imaging in diabetic retinopathy

Diabetic retinopathy (DR) is a complication of diabetes mellitus (DM) that may causes blindness. The vitreous is an extracellular matrix and it may have changes through liquefaction and syneresis in patients with DM, even in those without apparent DR. Diffusion-weighted imaging (DWI) is a new technique provide tissue contrast relying on difference with the diffusion of water molecules among tissues, which can be measured by the apparent diffusion coefficient (ADC) value. We aimed to investigate the vitreous of patients in different stages of DR using diffusion-weighted imaging technique. This prospective study included a group of 100 patients with DR and 100 members of an age- and gender-matched control group. All groups were tested using a head coil in conduction with a Achieva 1.5T magnetic resonans imaging (MRI) system (Philips Medical Systems, Best, The Netherlands). The mean ADC values were calculated and used for statistical comparisons. Mean duration of diabetes was 12.22±10.13 years in patients. Compared to controls, both eyes of the DR group had statistically and significantly lower values of ADC (p=0.025 and p=0.002, respectively). No significant correlations were found among the ADC values and central macular thickness, disease duration and stage of DR (all p>0.05) in patients. Mean ADC values revealed no significant differences among the subgroups of patients at different stages of DR (all p>0.05). Decreased ADCs in the vitreous of diabetes patients seem to be associated with the presence of diabetic retinopathy.

10. Assessment and optimization of PET contours recovery for respiratory-gated radiotherapy

Introduction The development of medical imaging, and more specifically functional imaging, open new perspectives for radiotherapy treatments. The joint use of the dosimetric CT and the PET improve the determination of target volume by combining functional and morphological data. The purpose of this study is to evaluate the recovery process of the PET contours for respiratory-gated radiotherapy according to two methods: the Replanning algorithm (RP) and the module Integrated Registration (IR) from General Electric (GE) Medical System. Methods The 4D acquisitions are achieved on a dosimetric CT Brillance Big Bore® (Philips Medical System) associated to an abdominal belt Pneumo chest Bellows (Lafayette Instrument) and on a PET/CT Discovery 710 (GE Medical System) coupled to the respiratory gating system RPM (Real-Time Position Management™, Varian Medical System). The Quasar™ Programmable Respiratory Motion Phantom (Modus Medical Device Inc) is used with a lung density insert. The lesions are simulated by solid spheres of 1 and 3 cm diameter and another empty one of 2 cm. The acquisitions have been performed with breathing amplitude of 2 and 4 cm and breathing frequency of 10, 15 and 20 bpm. The influence of the acquisition parameters, reconstruction parameters and variability of the patient parameters (amplitude, frequency, lesion size) are being assessed. On the CT images, the spheres are segmented with a threshold allowing to obtain theoretical volume of the sphere on a 3D acquisition. On the PET images, the spheres are segmented with a 42% threshold of the SUVmax. The PET/CT contours obtained with the RP algorithm and the IR module have been compared to the contours delineated on the dosimetric CT with Eclipse v13.5, using the Dice’s coefficient. Results The influence of the acquisition and reconstruction parameters studied with the RP algorithm show Dice’s coefficients ranging from 0.93 to 0.96. Dice’s coefficients variating between 0.85 and 0.94 are obtained for the study of variability of patients parameters. With regard to the two retrieval methods of PET contours, they show similar Dice’s coefficients. For an amplitude of 2 cm and a respiratory frequency of 15 bpm, the Dice’s coefficient is 0.84 with RP algorithm and 0.85 with the IR method. Conclusions For pulmonary lesions, the two retrieval methods of RP or IR contours appear similar. In the field of radiotherapy, a new way to use the replanning algorithm seems possible and allows for the simplification of the recovery of the PET contours. A clinical study is in the process of being evaluated. The objective is to validate this method in lung lesions cases.

Relational database of treatment planning system information

The purpose of the present work was to develop a relational database and associated applications to facilitate retrospective review of data present in radiation treatment plans. The data source was a commercial radiation treatment planning system (Pinnacle3, Philips Medical Systems, Milpitas CA), which is specifically characterized by an open data storage format and internal scripting capability. The database is an open-source, relational database (PostgreSQL, PostgreSQL Global Development Group, http://www.postgresql.org). The data is presented through a web interface in addition to being fully query-accessible using standard tools. A database schema was created to organize the large collection of parameters used to generate treatment plans as well as the parameters that characterized these plans. The system was implemented through a combination of the treatment planning systems internal scripting language and externally executed code. Data is exported in a way that is transparent to the user, through integration into an existing and routinely-used process. The system has been transparently incorporated into our radiation treatment planning workflow. The website-based database interface has allowed users with minimal training to extract information from the database.

P.99 - Reliability of DTI-based muscle-volumetry as compared to conventional T1-based manual segmentation

The purpose of this study is to compare two methods of muscle segmentation to assess muscle volumes in human calf muscles. In this prospective cross-sectional study, we evaluated lower leg muscles of 18 healthy volunteers (9 females, mean age 27.6 ± 3.8 years) using muscle diffusion tensor imaging (DTI) and tractography. MRI was performed using a 3T MRI (Achieva 3T X, Philips medical Systems) and a 16 channel Philips Torso XL coil. The lower legs were separated into two FOV to improve shimming. For every FOV a sequence of T1w, T2w and diffusion weighted imaging were acquired. Post procession was done with Mathematica 11 and ExploreDTI (running under Matlab). 3D fiber tractography and DTI analysis were performed for each whole muscle structure. Conventional volumetry based on T1w images was manually performed using 3D Slicer software. Correlation analysis between manual segmented volumes and DTI-based tractvolumes were performed as well as Cronbachs alpha analysis to assess reliability of outcome values. The tract-based volumetry showed a significantly positive correlation (p < 0.05) with conventional T1w based volumetry in every lower leg muscle (for both left and right legs). Internal consistency of both methods was found to be significant (Cronbachs alpha 0.656 – 0.908). Absolut volumes of DTI based volumetry show overall higher muscle volumes than the conventional T1w based volumetry. We could show that muscle DTI information can not only be used to assess microstructural muscle properties and DTI parameters, but can also be used to segment calf muscles and to estimate individual muscle volumes. This could be important for longitudinal evaluations or group comparisons of different muscle diseases with DTI. Muscle volume can provide additional disease specific information besides the diffusion specific information and can be acquired in the same sequence. The differences in absolute muscle volumes are most likely due to partial volume effects caused by different voxel size of T1w images and DTI-images.

Turning Adversity into Opportunity: Philips in Australia, 1945-1980

Philips Australia, the Australian subsidiary of Dutch MNE Philips Electronics, experienced difficulties during 1942–1943, when it came close to being nationalized as enemy property. In response, the company set out to improve its reputation in the local radio parts and electronics industry and in Australian markets. Its strategy of embedding itself in Australian society served the purpose of improving company performance and influencing the government policies that guided the rapid development of Australia’s postwar electronics industry. With this strategy, Philips Australia minimized the risks and maximized the commercial opportunities it faced. The firm localized senior management, maximized local procurement and local manufacturing, took a leading role in industry associations, engaged politically influential board members, and used marketing tools to build a strong brand and a positive public profile in Australia. However, the company became aware of the limitations of this strategy in 1973, when a new Labor government reduced trade protection. Increasing competition from Japanese electronics firms forced Philips Australia to restructure and downsize its production operations. Despite increasing reliance on imports from the parent company’s regional supply centers and efforts to specialize production on high-value added products, the firm saw its profitability and market share in Australia decrease.

EP04.08: Quantification of mechanical dyssynchrony in growth‐restricted fetuses and normal controls using speckle‐tracking echocardiography (STE)

To evaluate longitudinal mechanical dyssynchrony in normally grown fetuses by speckle-tracking echocardiography (STE) and to compare longitudinal mechanical dyssynchrony in fetal growth restriction (FGR) with normal controls. A prospective study was performed on 30 FGR and 62 normally grown fetuses, including 30 controls matched by gestational age, using STE and a transversal four chamber view. Data analysis was carried out with a high frame rate of about 175 frames/s. Dyssynchrony was analysed offline with QLab 9 (Philips Medical Systems, Andover, MA, USA) as time differences between peaks in strain of both ventricles and the septum. Inter- and intraventricular and intraseptal dyssynchrony were obtained and inter- and intraobserver reliability was analysed. Longitudinal mechanical dyssynchrony was feasible in all cases, with high inter and intraobserver reliability. Levels of inter and intraventricular dyssynchrony were higher in the FGR than in the control group. Speckle-tracking echocardiography (STE) is a reliable technique for cardiac function assessment in the fetal heart. Interventricular dyssynchrony could be a potential parameter for early detection of subclinical myocardial dysfunction before other parameters demand intervention. The future clinical role of longitudinal mechanical dyssynchrony needs to be verified in larger studies and with a technique customised for prenatal echocardiography.

Clinical and Radiation Diagnosisof Renal Arteriovenous Malformation

Purpose:to analyze the results of preoperative diagnosis and treatment of patients with renal arteriovenous malformation and compare them with the literature data.Materials and methods.5 patients with renal arteriovenous malformations were examined for the period from 2014 to2016 in the FSBI "A.V. Vishnevsky Institute of Surgery» MH RF, where simultaneously there are clinical departments of urology and vascular surgery, 4 of them were treated. All patients were female. The mean age was 31.8 ± 6.7 years (24–41 years). Ultrasound was done to all the patients in B-mode followed by a duplex scan using an abdominal 2–4 MHz convex. MDCT was performed in 4 patients out of 5. Patients underwent multiphase examination on a multidetector CT-scanner Philips Brilliance iCT-256 and Brilliance CT-64 (Philips Medical Systems (Cleveland) with the 120 kV and 100 kV protocols and an intravenous injection of the iodinated contrast agent. Digital subtraction angiography was performed in 3 patients.Results.One-sided lesion occurred in four cases (3 of them (60%) right-sided and 1 (20%) left-sided), in one patient (20%) arteriovenous malformation was bilateral As a result of the analysis of our own material and literature data, the diagnostic criteria of renal arteriovenous malformations according to ultrasound, MDCT and digital subtraction angiography were studied in detail. The results of the examinations of 5 patients with demonstration of ultrasound, MDCT and angiographic images are presented with the visualization of the characteristic features of renal AVM. In addition, the treatment options for such patients with the possibility of preserving the kidney are described.Conclusion.Duplex scanning is an effective method of diagnosis and postoperative follow-up of patients with renal arteriovenous malformations. Preoperative computed tomography and selective digital subtraction angiography provide accurate information about the renal angioarchitectonics and AV-shunts for choosing the treatment tactics and planning the surgical intervention.

Moderating Effects of Cortisol on Neural-Cognitive Association in Cognitively Normal Elderly Subjects.

Cortisol homeostasis is important for healthy brain and cognitive aging. The aim of the current study is to investigate the role of serum cortisol levels in the relationship between regional brain volumes and cognitive processing speed in a group of cognitively normal elderly subjects. Forty-one healthy elderly participants were from a parallel longitudinal study. The reported data in this study reflects baseline measurements. Whole-brain anatomical scanning was performed using a 3.0 Tesla Philips Medical Systems Achieva scanner. Cognitive processing speed was assessed by the digit-symbol and symbol search tests, from the Chinese version of the Wechsler Adult Intelligence Scale—third edition (WAIS-III). Serum cortisol levels (sampled in the late morning) were measured by ELISA kits. Whole-brain regression analysis revealed that serum cortisol levels positively predicted the white matter volumes (WMV) of the right thalamus, the gray matter volumes (GMV) of the left thalamus and right cerebellar tonsil, and negatively predicted the WMV and GMV of the left middle temporal gyrus (MTG) in 41 healthy elderly participants. Furthermore, serum cortisol significantly moderated the relationship between the GMV of the left MTG and processing speed, as well as the GMV of the left thalamus and processing speed. This study provided the first piece of evidence supporting serum cortisol levels in moderating the relationship between regional brain volumes and processing speed in healthy elderly subjects. This observation enriches our understanding of the role of cortisol in brain morphology and cognitive functioning.

Iterative dataset optimization in automated planning: Implementation for breast and rectal cancer radiotherapy.

To develop a new automated treatment planning solution for breast and rectal cancer radiotherapy. The automated treatment planning solution developed in this study includes selection of the iterative optimized training dataset, dose volume histogram (DVH) prediction for the organs at risk (OARs), and automatic generation of clinically acceptable treatment plans. The iterative optimized training dataset is selected by an iterative optimization from 40 treatment plans for left-breast and rectal cancer patients who received radiation therapy. A two-dimensional kernel density estimation algorithm (noted as two parameters KDE) which incorporated two predictive features was implemented to produce the predicted DVHs. Finally, 10 additional new left-breast treatment plans are re-planned using the Pinnacle3 Auto-Planning (AP) module (version 9.10, Philips Medical Systems) with the objective functions derived from the predicted DVH curves. Automatically generated re-optimized treatment plans are compared with the original manually optimized plans. By combining the iterative optimized training dataset methodology and two parameters KDE prediction algorithm, our proposed automated planning strategy improves the accuracy of the DVH prediction. The automatically generated treatment plans using the dose derived from the predicted DVHs can achieve better dose sparing for some OARs without compromising other metrics of plan quality. The proposed new automated treatment planning solution can be used to efficiently evaluate and improve the quality and consistency of the treatment plans for intensity-modulated breast and rectal cancer radiation therapy.

In the quest for degenerative lumbar spinal stenosis etiology: the Schmorl\u2019s nodes model

BackgroundDegenerative lumbar spinal stenosis (DLSS) is a common health problem in the elderly and usually associated with three-joint complex degeneration. Schmorl’s nodes (SNs) are described as vertical herniation of the disc into the vertebral body through a weakened part of the end plate that can lead to disc degeneration. Since SNs can harm the spine unit stability, the association between DLSS and SNs is expected. The aim of this study is to shed light on the relationship between degenerative lumbar spinal stenosis and SNs.MethodsTwo groups of individuals were studied: the first included 165 individuals with DLSS (age range: 40–88, sex ratio: 80 M/85 F) and the second 180 individuals without spinal stenosis related symptoms (age range: 40–99, sex ratio: 90 M/90 F). The presence or absence of SNs on the cranial and caudal end plate surfaces at the lumbosacral region (from L1 to S1 vertebra) was recorded, using CT images (Brilliance 64 Philips Medical System, Cleveland Ohio, thickness of the sections was 1–3 mm and MAS, 80–250). Chi-Square test was taken to compare the prevalence of SNs between the study groups (control and stenosis) by lumbar disc level, for each gender separately. Multivariable logistic regression analysis was also used to determine the association between DLSS and SNs.ResultsThe prevalence rate of SNs was significantly greater in the stenosis males (L1-2 to L5-S1) and females (L4-5 and L4-S1) compared to their counterparts in the control (P < 0.001). In addition, the presence of SNs in both males and females was found to increase the likelihood for DLSS.ConclusionsOur results indicate that SNs prevalence is significantly greater in the DLSS group compared to the control. Furthermore, SNs are strongly associated with DLSS.

Three-Dimensional Eye Shape, Myopic Maculopathy, and Visual Acuity: The Zhongshan Ophthalmic Center–Brien Holden Vision Institute High Myopia Cohort Study

To investigate the relationship among eye shape, myopic maculopathy, and visual acuity in highly myopic eyes using 3-dimensional (3D) magnetic resonance imaging (MRI). Observational case series. The study included 190 eyes of 95 participants with bilateral high myopia from the Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study, with spherical power ≤-6.00 diopters (D) in both eyes. The participants underwent best-corrected visual acuity (BCVA), fundus photography, cycloplegic refraction, and ocular biometry. Posterior staphyloma was identified with 3D MRI, and ocular shapes were categorized into spheroidal, ellipsoidal, conical, nasally distorted, temporally distorted, and barrel shapes according to the inferior view from T2-weighted 3D MRI (Achieva 3.0T; Philips Medical Systems, Best, the Netherlands). Myopic maculopathy was graded as C0 to C4 according to the International Photographic Classification and Grading System using fundus photography. The statistical significance of the differences in distribution of myopic maculopathy and BCVA in eyes with different ocular shapes was determined using Pearson's chi-square tests. Distributions of myopic maculopathy and BCVA in relation to different eye shapes. The mean spherical equivalent and axial length were-11.74±4.10 D and 28.18±1.73 mm in the right eyes, respectively. The same ocular shapes were observed in both eyes in 69 participants (72.6%). The predominant shape was spheroidal (53.7%), followed by nasally distorted and conical types (both 14.7%). C2 and above myopic maculopathy was observed in all barrel-shaped eyes, in 75% temporally distorted eyes, and in 71.4% nasally distorted and conical eyes. In eyes with posterior staphyloma (n= 22), 18 (81.8%) had C2 and above myopic maculopathy compared with 40 eyes (54.8%) without posterior staphyloma (n= 73). Eyes with temporal and nasal distortion, and eyes with staphyloma were more likely to have BCVA <20/40. Not all highly myopic eyes are deformed. Spheroid was the predominant ocular shape in this series of young patients with high myopia bilaterally. Barrel-shaped and temporally distorted eyes present significant myopic maculopathy, whereas eyes with posterior staphyloma display more severe chorioretinal atrophy. Eyes of more deformed shapes tend to have more severe myopic maculopathy and worse BCVA.

Nokia's Supply Chain Management

In March 2000 a fire broke out at the Royal Philips Electronics plant, damaging its supply of semiconductor chips. Nokia Corporation and Ericsson LM relied on these chips to produce their cell phones; together they received 40 percent of the plant's chip production. Both companies were about to release new cell phone designs that required the chips. At Nokia, word of the setback spread quickly up the chain of command. Nokia's team, which had a crisis plan in place, sprang into action. With an aggressive, multipronged strategy, Nokia avoided any cell phone production loss. In contrast, the low-level technician who received the information at Ericsson did not notify his supervisors about the fire until early April and had to scramble to locate new sources for the chips. This search delayed production and proved a fatal blow to Ericsson's independent production of mobile phones. Nokia's handling of its supply chain disruption provides a dramatic example of how a company's strategic risk management can alleviate financial disaster and lay the groundwork for success in the future. Perturbations in supply chain management are inevitable, and grow harder and harder to assess as the marketplace becomes more globalized.Students will learn the following concepts: