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Ethical and legal issues are common in long-term care and are separate, but closely interrelated. Health care ethics is the application of values (patient, caregiver and societal) to the process of clinical decision-making. This process requires the intellectual and empathetic weighing of values, facts and prognostications in order to produce a supportable decision. Clinicians often encounter competing values, e.g., the right of self-determination of an individual versus the interests of society as a whole, and must take into consideration the facts, as well as the likelihood and consequences of various outcomes.

This paper describes the conception and the development of a real-time data-acquisition system for prototype detectors of the Tracker being designed for the compact muon solenoid (CMS) experiment at the Large Hadron Collider of CERN, European Laboratory for Particle Physics, Geneva, Switzerland. The rationale for the development of a dedicated data-acquisition system was the need to perform two fundamental beam tests (the "Milestone Barrel 1" and "Milestone Forward 1"), with large-scale prototypes of the detectors planned as the baseline design. The number of readout channels, the complexity of the readout electronics, and the stringent requirements of the milestone tests mandated that a thorough understanding of the issues related to the physics of the detectors themselves be coupled with the application of leading-edge electronic and software engineering technologies. The implementation described in this paper is based on a distributed architecture. An event builder CPU handles the two main tasks of synchronizing a variable number of front-end processors and formatting the data in preparation for the transfer to a dedicated high-performance storage system, while the front-end processors handle the hardware and the real-time readout. Additional workstations are used to decouple the actual task of transferring the data files and monitoring the detector performance on-line from the readout farm. The system has been successfully operated during the two aforementioned Milestone tests, allowing the CMS Tracker collaboration to pass them, with the simultaneous readout of up to 40000 detector channels. The results of the two Milestones have led to the compilation of the "Tracker Technical Design Report". Subsequently, the same readout system has been used for a number of other beam tests, and it has formed the basis for the development of further, more advanced data-acquisition systems for the new readout electronic of the CMS Tracker.

In order to check the system aspects of the forward-backward MSGC tracker designed for the future CMS experiment at LHC: 38 trapezoidal MSGC counters assembled in six multi-substrates detector modules were built and exposed to a muon beam at the CERN SPS. Results on the gain uniformity along the wedge-shaped strip pattern and across the detector modules are shown together with measurements of the detection efficiency and the spatial resolution. (C) 1999 Elsevier Science B.V. All rights reserved.

Sixty patients presenting for in-patient gynaecological laparoscopic surgery were randomly allocated to receive either diclofenac 75 mg ( n = 20), ketorolac 30 mg ( n = 20) or piroxicam 20 mg ( n = 20) as an intramuscular (i.m.) injection immediately after induction of anaesthesia. Post-operative Visual Analogue Scores at rest, over the first 24 h after surgery, using a 10 cm scale, ranged from 3.2–0.5 in the diclofenac group, 2.7–0.85 in the ketorolac group and 2.8–0.5 in the piroxicam group. The scores did not differ significantly between the three groups ( P > 0.05). Mean time (SD) to first analgesia was 27 (94) min in the piroxicam group, 16 (30) min in the diclofenac group and 62 (120) min in the piroxicam group. Six out of 20 patients in the diclofenac group required further analgesia compared with nine out of 20 in the other two drug groups, this was not significant. There were no reports of increased bleeding, bronchoconstriction, bleeding from the upper gastrointestinal tract, renal impairment or pain from the intramuscular (i.m.) injection site in any of the groups. The administration of a non-steroidal anti-inflammatory drug to patients presenting for laparoscopic surgery reduces post-operative pain and analgesic requirements, and piroxicam 20 mg provides a suitable alternative to 75 mg diclofenac and 20 mg ketorolac.

In most Positron Emission Tomography (PET) systems dedicated to small animal imaging, the geometry of the detector module is based on a block structure where the crystal elements are coupled to a reduced number of photomultiplier tubes (PMT). In this configuration, the spatial resolution and the detection efficiency depend on the crystal dimensions and thus there is a correlation between these two figures of merit. In this paper, we present a method already used by Ter-Pogossian in the 1970s allowing the spatial resolution and the detection efficiency to be independent of each other. The crystals are oriented in the axial direction readout on both sides by individual photodetector channels. The spatial resolution in the transverse plane is driven by the crystal section and the spatial resolution in the axial direction is proportional to the contrast of the light collected on both sides of the crystal. The detection efficiency depends on the number of radial crystal layers and the geometry of the system. With the perfect knowledge of the interaction depth, the inner diameter of the PET system can be reduced to a minimum value leading to an increase in detection efficiency. We investigate two particular geometries dedicated to mouse and whole purpose studies and based on the same detection module. Each module consists on a matrix of 32 $,times,$24 LYSO:Ce crystals of 1.5 mm$,times,$1.5 mm$,times,$25 mm each read at both ends by a Photonis Corp multi-channel plate photodetector. The surface treatment is optimized to reach a volumetric spatial resolution of 1 mm$^{3}$. The detection efficiency of each system is evaluated using Monte Carlo simulation. The mouse and whole purpose systems a- - re based on 4 and 6 modules with an inner diameter of 61.2 mm and 103.2 mm where the axial extent is 25 mm leading to a detection efficiency of 18% and 13%, respectively. This geometrical configuration leads to a detection efficiency close to the system solid angle with a volumetric spatial resolution of 1 mm$^{3}$ .

During the last decades, small animal imaging has shown an increasing interest in Single Photon Computed Tomography since animal models can mimic human diseases enabling a translation of results and conclusions of research done on animals to humans. SPECT equipped with a pinhole type collimator provides high resolution for in vivo imaging leading to an accurate quantitative measurement especially in small volume of interest.

Recent researches in PET instrumentation tend to improve the reconstructed spatial resolution using the gamma ray Depth Of Interaction (DOI) information. This method, already introduced by Moses et al., requires reading both ends of a scintillating crystal to be efficient. The recorded charges obtained by the two photodetector such as Photomultiplier Tubes (PMT) or Avalanche PhotoDiodes (APD) are dependent on the depth gamma ray interaction. Braem et al. recently used the contrast calculated as the ratio between the difference of the recorded charges and their sum to improve the DOI spatial resolution. In this work, we investigate the optimization of the crystal length and coating to improve the depth of interaction spatial resolution in PET applications. For a 1.5 × 1.5 mm2 LYSO:Ce crystal section read at both ends by PMT, we find that a length of 25 mm and a coating made with PMMA and 30% of TiO 2 are appropriate to reach a DOI spatial resolution of 1 mm.

Some current researches based on small animal model are dedicated to functional cerebral imaging which represents a fundamental tool to understand the mechanisms involved in neurodegenerative diseases. In the radiopharmaceutical development approach, the main challenge is to measure the radioactivity distribution in the brain of a subject with good temporal and spatial resolutions in order to investigate the behaviors of new radiopharmaceuticals inside the injected subject. In the case where the isotope is a single photon emitter, we present a 1 D gamma counter to investigate the possibility to obtain both high detection efficiency and good spatial resolution to access the kinetic of radiopharmaceutical in the brain of a mouse. The system consists in a 64 channels Multi-Anode PhotoMultiplier Tube (H8804, Hamamatsu Corp.) coupled to a highly segmented YAP:Ce crystal consisting of 32 strips of 0.575 × 18.4 × 10 mm3. The collimation is made of 33 tungsten slats of 100 μm thick with a 40 mm height optimized using GEANT4 Monte Carlo simulations. For a field of view of 18.4 × 18.4 mm2, the intrinsic spatial resolution is equal to 575 μm with a total detection efficiency of 0.29% for an extended source. The geometry of this new gamma counter gives one kinetic curve per strip to finally get the radiopharmaceutical kinetic in the whole brain of the mouse. To obtain a 2D projection of the brain radioactivity distribution, a spin rotation procedure can be applied. The gamma counter can also be combined to a microCT system to obtain anatomical information.

Background Sentinel lymph node (SLN) procedure is now a widely accepted method of LN staging in selected invasive breast cancers (unifocal, size ≤ 2 cm, clinically N0, without previous treatment). Complete axillary clearance is no longer needed if the SLN is negative. However, the oncological safety of this procedure remains to be addressed in randomized clinical trials. One main pitfall is the failure to visualize SLN, resulting in incorrect tumor staging, leading to suboptimal treatment or axillary recurrence. Operative gamma cameras have therefore been developed to optimize the SLN visualization and the quality control of surgery. Case presentation A 44-year-old female patient with a 14-mm infiltrative ductal carcinoma underwent the SLN procedure. An operative gamma camera was used during and after the surgery. The conventional lymphoscintigraphy showed only one SLN, which was also detected by the operative gamma camera, then removed and measured (9.6 kBq). It was analyzed by frozen sections, showing no cancer cells. During this analysis, the exploration of the axillary area with the operative gamma camera enabled the identification of a second SLN with low activity (0.5 kBq) that conventional lymphoscintigraphy, surgical probe and blue staining had failed to visualize. Histological examination revealed a macrometastasis. Axillary clearance was then performed, followed by a postoperative image proving that no SLN remained. Therefore, the use of the operative gamma camera prevented an under-estimation of staging which would have resulted in a suboptimal treatment for this patient. Conclusion This case report illustrates that an efficient operative gamma camera may be able to decrease the risk of false negative rate of the SLN procedure, and could be an additional tool to control the quality of the surgery. Trial Registration ClinicalTrials.gov Identifier: NCT00357487

Large field of view gamma cameras are widely used to perform lymphoscintigraphy in the sentinel lymph nodes (SLN) procedure in case of breast cancer. However, they are not specified for this application and their sizes do not enable their use in the operative room to control the excision of the all SLN. We present the results obtained with a prototype of a new mini gamma camera developed especially for the operative lymphoscintigraphy of the axillary area in case of breast cancer. This prototype is composed of 10 mm thick parallel lead collimator, a 2 mm thick GSO:Ce inorganic scintillating crystal from Hitachi and a Hamamatsu H8500 flat panel multianode (64 channels) photomultiplier tube (MAPMT) equipped with a dedicated electronics. Its actual field of view is 50 × 50mm2. The gamma interaction position in the GSO scintillating plate is obtained by calculating the center of gravity of the fired MAPMT channels. The measurements performed with this prototype demonstrate the usefulness of this mini gamma camera for the pre, per and post-operative identification of SLN's and how its complementary role with an intraoperative handheld gamma probe enables to improve the efficiency of this practice. A 100 × 100mm2 field of view camera designated to cover the entire axillary area is under investigation.

The aim of this study was to evaluate the ability of a prototype intraoperative mini -camera, the CarolIReS, with a 50 x 50 mm field of view, to precisely localize sentinel lymph nodes (SLNs) and to determine their depth in a series of patients with infiltrative breast cancer requiring SLN excision. Methods: With the use of phantoms, the broadness of the signal of an acquired projection was shown to linearly depend on its distance from the collimator. A preclinical ex vivo study of 25 excised SLNs demonstrated that SLN size did not influence depth estimation. The minimum activity threshold for successful use of the proposed method was determined. After a preoperative radioisotope injection and lymphoscintigraphy, the SLN was localized in a series of 11 patients using both the mini -camera and a -probe. During surgery, a ruler was used to measure the depth of all SLNs before their excision. Results: Using the measured linear dependence of image broadness, we found that the expected SLN anatomic depth was compatible with its measured depth during surgery. Conclusion: This study showed that the mini -camera efficiently estimated the location of SLNs in 3 dimensions

A small series production of detector modules made of MicroStrip Gas Counters (MSGC) and a Gas Electron Multiplier (GEM) foil has been exposed to a high-intensity hadron beam, We report about the reproductibility and stability of the detector responses and about the occurrence and consequences of discharges in the detector, The interdependence of the four voltage differences used in the detector has been studied by Simulation and with X-ray measurements. Rate dependence of the signal amplitude is observed. The behaviour of the MSGC + GEM is compared to that of a state-of-the-art MSGC. Influence of various parameters on the detector response is investigated. (C) 2002 Elsevier Science B.V. All rights reserved.

The trigger for the first compact muon solenoid (CMS) tracking beam tests is a dedicated system for analog multiplexed front-end electronics. With this first generation of electronics dedicated to CMS tracker detectors, some new specific development was necessary to read it with a multicrate distributed data acquisition (DAQ) system. The goal of this development was to reach a high scalability of experiment subsystems and a good robustness for test beams. Each subsystem had to be independent from the others, both from the hardware and software point of view. Remote control software for this system as well as further monitoring facilities were the required functions of the trigger system.

Myositis ossificans is a benign condition resulting from severe muscular contusion manifested by heterotrophic bone forma tion. The process is common in the anterior thigh but the literature dealing with myositis ossificans in the upper arm is limited. Ten cases of the condition in the upper arm were seen in our practice. All 10 were the result of football injuries and exhibited one or more of the triad of local pain, a hard palpable mass in the muscle, and a flexion contracture of the elbow. Seven of the cases (70%) were asymptomatic or significantly improved in less than 3 months with conservative nonoperative management. Three patients (30%) underwent surgery because the painful mass persisted. In two (66%) of the surgically managed cases, there was clinical and radiographic evidence of recurrence postoperatively in spite of delaying excision until radiographic parameters of maturation were present.

The design of a TPC for a high-multiplicity environment is described. The sense plane is composed of a matrix with 40 rows of short anode wires. The end-cap is completed with rod and wire electrodes to establish the amplification region and to minimize space charge effects. The digital readout of more than 6000 channels is performed by a combination of purpose-built comparators and FASTBUS TDCs. The performance of the chamber is briefly described, and some ideas to improve the hit efficiency and resolution in a new end-cap design are discussed. © 1989.

Experience with the NA36 high-speed FASTBUS-based data acquisition system is presented. The multicrate system operates with a 35 m cable segment and extensive local data compression and processing. The principle data sources are a time projection chamber and associated calorimetry. A special FASTBUS interface was developed for drift- and proportional chamber readout. © 1989.