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BACKGROUND. Tearing of the superior peroneal retinaculum is a known cause of peroneal tendon subluxation-dislocation. However, with the exception of cortical avulsions at the fibular attachment, superior peroneal retinaculum injury and subsequent peroneal tendon subluxation-dislocation are typically radiographically occult. OBJECTIVE. The purpose of this study was to evaluate the previously undescribed association between radiographic fibular tip periostitis and MRI evidence of peroneal tendon subluxation-dislocation in patients with hindfoot valgus. METHODS. Thirty-five patients with radiographic fibular tip periostitis and 35 ageand sex-matched individuals without periostitis were selected from among 220 consecutively registered patients with hindfoot valgus who had undergone both ankle radiography and MRI. Studies were retrospectively assessed by two musculoskeletal radiologists in consensus and by two additional blinded radiologists independently for the presence of peroneal tendon subluxation-dislocation, presence of subfibular impingement, and hindfoot valgus angle measurements. Interobserver agreement and accuracy, sensitivity, and specificity in the detection of fibular periostitis, peroneal tendon subluxation-dislocation, and subfibular impingement were calculated, and Fischer exact, Mann-Whitney, kappa coefficient, and intraclass correlation tests were performed. RESULTS. Both the consensus and the two independent interpretations showed that the frequency of peroneal tendon subluxation-dislocation was significantly greater in the group with periostitis (62.9%, 65.7%, and 85.7%) than in the group without periostitis (5.7%, 0%, and 14.3%) (p < .001). The finding of periostitis was specific and highly sensitive for predicting peroneal tendon subluxation-dislocation. The frequency of subfibular impingement was also statistically higher in the group with periostitis than in the group without it (p < .001). The hindfoot valgus angle was statistically larger in the group with periostitis than in the control group (p = .01-.002) and among patients with versus those without peroneal tendon subluxation-dislocation (p = .002 to p < .001). The blinded readers had substantial or almost perfect agreement on all imaging interpretations (concordance rate, 82.9-95.7%; κ = 0.66-0.91). CONCLUSION. The radiographic finding of fibular tip periostitis in patients with hindfoot valgus can be a predictor of peroneal tendon subluxation-dislocation and may also suggest advanced hindfoot valgus and subfibular impingement. These radiographic associations should be recognized by the radiologist, and MRI may be recommended as clinically indicated. CLINICAL IMPACT. Chronic undiagnosed peroneal tendon subluxation-dislocation can be a persistent cause of lateral ankle pain, leading to further degeneration and the possibility of complete peroneal tendon tears. Distal fibular periostitis in patients with hindfoot valgus can be a reliable radiographic indicator of this entity and may suggest the presence of subfibular impingement.

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BACKGROUND. Literature on glenohumeral dislocations has focused on younger patient populations because of high recurrence rates. However, the spectrum of injuries sustained in younger versus older patient populations is reported to be quite different. OBJECTIVE. The purpose of this article is to describe MRI findings and management of anterior shoulder instability in the aging (≥ 60 years) population. METHODS. Shoulder MRI examinations of anterior glenohumeral dislocations in patients 40 years old and older were subdivided into groups younger than 60 years old or 60 years old and older and reviewed by two musculoskeletal radiologists for a Hill-Sachs lesion, other fracture, glenoid injury, capsulolabral injury, rotator cuff tear, muscle atrophy, and axillary nerve injury. Fischer exact test and logistic regression was evaluated for significant differences between cohorts, and interreader agreement was assessed. Surgical management was recorded, if available. RESULTS. A total of 104 shoulder MRI examinations (age range, 40-79 years; mean age, 58.3 years; 52 women, 52 men) were reviewed (54 examinations < 60 years; 50 examinations ≥ 60 years). Acute high-grade or full-thickness supraspinatus (64.0% vs 37.0%; p = .001), infraspinatus (28.0% vs 14.8%; p = .03), and subscapularis (22.0% vs 3.7%; p = .003) tears were more common in the group 60 years old and older. Hill-Sachs lesions were more common in the younger group (81.5% vs 62.0%; p = .046). Greater tuberosity fractures were seen in 15.4% of the overall cohort, coracoid fractures in 4.8%, and acute axillary nerve injuries in 9.6%. Interreader concordance was 88.5-89.4% for rotator cuff tears and 89.4-97.1% for osseous injury. In the group younger than 60 years old, 11 of 37 subjects (29.7%) had rotator cuff repair and 11 of 37 (29.7%) had labral repair, whereas 17 of 36 (47.2%) of the older group underwent rotator cuff repair, six of 36 (16.7%) underwent reverse shoulder arthroplasty, and six of 36 (16.7%) underwent labral repair. CONCLUSION. Radiologists should have a high index of suspicion for acute rotator cuff tears in anterior shoulder instability, especially in aging populations. Greater tuberosity or coracoid fractures and axillary nerve injury occur across all ages, whereas Hill-Sachs injuries are more common in younger patients. CLINICAL IMPACT. Acute high-grade or full-thickness rotator cuff tears are seen with higher frequency in older populations after anterior glenohumeral dislocation. Osseous and nerve injuries are important causes of patient morbidity that if not carefully sought out may be overlooked by the interpreting radiologist on routine imaging.

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Background@#Being at the frontline, nurses working in hospital settings are vulnerable to a range of experiences that impact their wellbeing. Measures to protect their health and welfare during the COVID-19 pandemic have been the focus of discussion among policymakers and administrators. There is a need to collectively understand their personal experiences to inform relevant policy decisions.@*Objective@#To synthesize and present the best available evidence describing the experiences of nurses working in hospital settings during the COVID-19 pandemic.@*Design@#This is a rapid review using Tricco's seven stage process. @*Data sources@#A structured search using PubMed, CINAHL, Scopus, and a local database Herdin was conducted.@*Review Methods@#A rapid review of studies published from January to August 2020, describing nurses' experiences of working in hospital facilities during the COVID-19 pandemic were included regardless of methodology. Following data screening and extraction, a narrative synthesis of the findings was conducted.@*Results@#Nineteen articles were included in the review. The experiences of nurses described in these articles generated a total of fifteen categories, based on similarities of meaning. Four synthesized findings were identified from the categories: (a) supportive nursing culture; (b) physical, emotional, and psychological impact of frontline work; (c) organizational responsiveness; (d) and maintaining standards of care.@*Conclusions@#Nurses' experiences working in hospital settings during the COVID-19 pandemic are diverse, profound, and dependent on the context of practice and prevailing healthcare system and organization. These experiences reflect personal encounters and shifts in healthcare delivery that ensure protection and safety while maintaining standards of care. Robust studies are needed to capture and explore the breadth of these experiences and heighten the discussions that advocate for nurses' welfare and safety during pandemics.

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PURPOSE: To develop and validate an Optically Stimulated Luminescent (OSL) dosimeter for exposure control verification of x-ray projection mammography imaging systems. METHODS: The active detection element of the dosimeter is a strip of OSL material 3.0 mm wide, 0.13 mm thick and 30.0 mm long with an overlying aluminum step wedge with thicknesses of 0, 0.2, 0.4 and 0.6 mm Al, encapsulated in a light-tight plastic enclosure with outer dimensions of 10.0 mm wide, 5.4 mm thick, and 54.0 mm long. The dosimeter is used in conjunction with a breast phantom for the purpose of estimating the half-value layer (HVL), entrance surface exposure (ESE), and average glandular dose (AGD) in conventional projection mammography. ESE and HVL were computed based on analysis of exposure profiles obtained from exposed strip dosimeters. The AGD was estimated by multiplying the ESE by the appropriate exposure to dose conversion factor for the thickness and % glandular tissue fraction represented by the phantom and target-filter combination employed. The accuracy and reproducibility of the ESE, HVL and AGD estimates obtained using the dosimeter positioned on the surface of the ACR phantom at the chest wall edge, was evaluated using mammography systems utilizing different imaging receptor technology, i.e. screen-film (SF), computed radiography (CR) and direct radiography (DR) and compared against results obtained using a calibrated ion chamber fitted with a mammography probe. RESULTS: ESE, AGD and HVL results obtained using the OSL mammography QA dosimeter agreed with results obtained using an ion chamber to within 5-10%, depending on the target-filter combination used. Repeat readings were highly consistent with a coefficient of variation = 5%. CONCLUSIONS: The OSL mammography QA dosimeter has been shown to effectively estimate ESE, HVL and AGD, demonstrating its usefulness for secondary monitoring of output exposure of mammography imaging systems.

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The maize pathogens Fusarium verticillioides (Fv) and Fusarium proliferatum (Fp) are morphologically very similar to one another, so Fp isolates have been often mistaken as Fusarium moniliforme (the former name of Fv). The only presently accepted morphological discriminator between these species is the presence/absence of polyphialides. Here, a collection of 100 Fusarium strains, isolated from infected maize kernels on plants grown in north-western Italy, were assigned as Fv or Fp on the basis of the presence/absence of polyphialides. This classification was tested on a subset of isolates by sexual crosses, ITS and calmodulin sequencing and AFLP profiling. An ITS-RFLP assay was extended to the full collection and to a number of Fv and Fp isolates of different geographical origin and hosts. The ITS region is proposed as taxonomically informative for distinguishing between Fp and Fv.

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BACKGROUND: Hippocampal atrophy--particularly of the CA1 region--may be useful as a biomarker for Alzheimer's disease (AD) or the risk for AD. The extent to which the AD hippocampus can be distinguished in vivo from changes due to normal aging or other processes that affect the hippocampus is of clinical importance and is an area of active research. In this study, we use structural imaging techniques to model hippocampal size and regional shape differences between elderly men with incident AD and a non-demented comparison group of elderly men. METHODS: Participants are Japanese-American men from the Honolulu Asia Aging Study (HAAS). The HAAS cohort has been followed since 1965. The following analysis is based on a sub-group of men who underwent MRI examination in 1994-1996. Participants were diagnosed with incident AD (n=24: age=82.5+/-4.6) or were not demented (n=102: age=83.0+/-5.9). One reader, blinded to dementia diagnosis, manually outlined the left and right hippocampal formation using published criteria. We used 3D structural shape analysis methods developed at the Laboratory of Neuro Imaging (LONI) to compare regional variation in hippocampal diameter between the AD cases and the non-demented comparison group. RESULTS: Mean total hippocampal volume was 11.5% smaller in the AD cases than the non-demented controls (4903+/-857 mm(3) vs. 5540+/-805 mm(3)), with a similar size difference for the median left (12.0%) and median right (11.6%) hippocampus. Shape analysis showed a regional pattern of shape difference between the AD and non-demented hippocampus, more evident for the hippocampal body than the head, and the appearance of more consistent differences in the left hippocampus than the right. While assignment to a specific sub-region is not possible with this method, the surface changes primarily intersect the area of the hippocampus body containing the CA1 region (and adjacent CA2 and distal CA3), subiculum, and the dentate gyrus-hilar region.

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Intracranial aneurysms are the primary cause of non-traumatic subarachnoid hemorrhage. Difficulties in identifying which aneurysms will grow and rupture arise because the physicians lack important anatomic and hemodynamic information. Through simulation, this data can be captured, but visualization of large simulated data sets becomes cumbersome, often resulting in visual clutter and ambiguity. To address these visualization issues, we developed an algorithm that extracts a skeleton of the patterns in 3D, time-dependent blood flow. The algorithm decomposes the blood flow into "bare-bones" components that can be visualized individually or superimposed together to formulate an understanding of the flow patterns in the aneurysm.

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Clinical data sets for neuroradiological cases can be quite large. A typical brain tumor patient at UCLA will undergo 8-10 separate studies over a 2 year period, each study will produce 60-100 magnetic resonance (MR) images. Gathering and sorting through a patient s imaging events during the course of treatment can be both overwhelming and time consuming. The purpose of this research is to develop an intelligent pre-fetch and hanging protocol that automatically gathers the relevant prior examinations from a picture archiving, and communication systems (PACS) archive and sends the pertinent historical images to the diagnostic display station where the new examination is subsequently read out. The intelligent hanging protocol describes the type of layout and sequence for image display. We have developed a classification scheme to organize the pertinent patient information to selectively pre-fetch and intelligently present the images to review brain tumor cases for a diagnostic neuroradiology workstation.

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Three-dimensional (3D) computer modeling, simulation, and rendering techniques were used to redesign the diagnostic workstations and radiology reading rooms for a proposed hospital with particular attention given to lighting conditions, noise reduction, and optimal use of limited workspace. The results were presented to a panel of multidisciplinary experts and iteratively improved and redesigned with the development or addition of new design criteria or requirements. These 3D techniques allowed faster, more efficient design and presentation of multiple options than is possible with traditional two-dimensional drawings, thereby expediting decision making and resulting in significant savings. The current workstation designs can easily be developed and implemented with available technology at a reasonable cost. They can also accommodate anticipated advances in computer and display technology as well as new imaging paradigms (eg, changes in keyboard and control ergonomics such as adjustable virtual keys on touch-sensitive screens, digital drawing tablets for annotations and controls, direct film digitizing, personal identification devices, offline media readers such as compact disks and digital videodisks, and speech recognition and voice activation). Use of 3D techniques in designing other parts of the radiology department (eg, examination rooms, technologists' areas, physicians' offices) could greatly improve and facilitate the design and implementation of complex settings in these work areas.

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Blood flow rate and velocity are important parameters for the study of vascular systems, and for the diagnosis, monitoring and evaluation of treatment of cerebro- and cardiovascular disease. For rapid imaging of cerebral and cardiac blood vessels, digital x-ray subtraction angiography has numerous advantages over other modalities. Roentgen-videodensitometric techniques measure blood flow and velocity from changes of contrast material density in x-ray angiograms. Many roentgen-videodensitometric flow measurement methods can also be applied to CT, MR and rotational angiography images. Hence, roentgen-videodensitometric blood flow and velocity measurement from digital x-ray angiograms represents an important research topic. This work contains a critical review and bibliography surveying current and old developments in the field. We present an extensive survey of English-language publications on the subject and a classification of published algorithms. We also present descriptions and critical reviews of these algorithms. The algorithms are reviewed with requirements imposed by neuro- and cardiovascular clinical environments in mind.

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Information technology is becoming a vital component of all health care enterprises, from managed care services to large hospital networks, that provides the basis of electronic patient records and hospital-wide information. The rationale behind such systems is deceptively simple: physicians want to sit down at a single workstation and call up all information, both clinical data and medical images, concerning a given patient. Picture archiving and communication systems (PACS) are responsible for solving the problem of acquiring, transmitting, and displaying radiologic images. The major benefit of PACS resides in its ability to communicate images and reports to referring physicians in a timely and reliable fashion. With the changes in economics and the shift toward managed and capitated care, the teleradiology component of PACS is rapidly gaining momentum. In allowing remote coverage of multiple sites by the same radiologists and remote consultations and expert opinion, teleradiology is in many instances the only option to maintain economically viable radiologic settings. The technical evolution toward more integrated systems and the shift toward Web-based technology is rapidly merging the two concepts of PACS and teleradiology in global image management and communication systems.

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A web-based video transmission of images from CT and MRI consoles was implemented in an Intranet environment for real-time monitoring of ongoing procedures. Images captured from the consoles are compressed to video resolution and broadcast through a web server. When called upon, the attending radiologists can view these live images on any computer within the secured Intranet network. With adequate compression, these images can be displayed simultaneously in different locations at a rate of 2 to 5 images/s through a standard local-area network. While the quality of the images was insufficient for diagnostic purposes, our users survey showed that they were suitable for supervising a procedure, positioning the imaging slices, and for routine quality checking before completion of a study. The system was implemented at UCLA to monitor nine CT's and six MRI's distributed in four different buildings. This system significantly improved the radiologists productivity by saving valuable time spent in trips between reading rooms and examination rooms. It also improved patient care and throughput by reducing the time spent waiting for the radiologists to check a study before removing the patient from the scanner.

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Synthetic materials currently used for arterial grafts can provoke serious complications such as infection, rejection, and incomplete reendothelialization. Porcine small intestinal submucosa (SIS) allografts (homografts) may not share these disadvantages yet still may provide an effective graft alternative. This study was designed to provide additional information concerning the performance of this material when used as an allo-patch graft. A porcine model was selected to enable hemodynamic comparisons to the adult human physiology. Slaughterhouse small intestine was used to prepare the SIS graft material. A well-vascularized section ofjejunum was resected, rinsed, and maintained in 0.9% NaCl solution containing 10% gentamicin. The graft was prepared by removing the serosal layer, inverting the material, and discarding the mucosal surface in a similar manner. The remaining submucosa and stratum compactum constituted the graft material and was subdivided into sizes from 1.5 to 3.0 cm2 tacked to foil for manageability, and was returned to the gentamicin solution. The surgery was initiated with a femoral arterial line in the anesthetized swine, followed by isolation and preparation of the infrarenal aorta for grafting. Cross-clamps were applied and a 1.0 x 1.5-cm section of aortic wall was resected. Two sides of allograft were freed from the foil and sewn into the aorta. Then the remaining sides were removed from the foil and final graft placement was completed. The graft was harvested at postoperative day 28 and presented for microscopic examination. Results confirmed that reendothelialization with neovascularization had occurred during this interval.

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The visualization of volumetric medical images and static or time-dependent vector fields is performed on personal computers over the Web using an interactive 3D interface based on VRML and Java. The VRML client obtains field information and the surface models of examined objects from a server accessible over the Internet. Various virtual tools enable radiologists and referring physicians to visualize and manipulate complex data sets using a simple interface on low-cost computers.

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Several different algorithms have been reported for measurement of blood flow rates and velocities from digital x-ray angiograms. We compare four videodensitometric methods: (1) distance-density curve matching (DDCM), (2) distance-density curve matching with curve-fitting (DDCM-F), (3) bolus mass tracking with curve-fitting (BMT-F) and (4) fluid continuity method (FCM). We tested the flow algorithms with simulated angiograms and with images obtained from a programmable flow phantom under clinically realistic flow and contrast injection conditions including imperfect mixing. All methods perform well for simulated angiograms. On phantom angiograms with constant flow, all methods tended to underestimate flow velocities by at least 7% and demonstrate high variability between consecutive measurements. The FCM demonstrated relatively low variability, but a large negative bias. The DDCM method was moderately biased and had the highest variability. The BMT-F method demonstrated the lowest bias (-7.1%) and the lowest variability both within (27%) and between (27%) studies. No method yields reliable measurements near the peak contrast opacification, when little or no gradient of contrast is present. The extrapolating version of the BMT-F method was also the most robust for estimation of interframe displacements longer than the field of view.

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Arruda and colleagues [Arruda, J.E., Weiler, M.D., Valentino, D.A. et al., 1996. A guide for applying principal-component analysis and confirmatory factor analysis to qEEG data. Int. J. Psychophysiol. 23, 63-81.] recently described seven neurophysiological measures that were previously derived and confirmed using factor analytic procedures and the quantitative electroencephalogram (EEG) sampled from 208 normal controls during an auditory continuous performance test (CPT). The purpose of the present investigation was to further test the validity of these empirically derived measures by examining each measure's relationship with CPT-related declines in performance. Participants were 48 right-handed men (n = 13) and women (n = 35) who reported being free of any neurological condition, birthing complications, or loss of consciousness greater than 2 min. After completing an eyes-closed resting condition, participants performed a 23-min CPT while both quantitative EEG and behavioral performance were measured at 45, 405, 765 and 1125 s into the CPT. Bipolar recordings were gathered using the International 10-20 system, from eight sites: frontal, fronto-temporal, temporal and temporal-occipital. Multivariate and follow-up univariate tests suggest the existence of a neurophysiological system located within the right temporal region that appears essential for the maintenance of a sustained attentional state. If confirmed, the further quantification of this neurocognitive system may prove useful as part of a clinical diagnostic workup.

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Recent advances in magnetic resonance imaging (MRI) are rapidly making this modality the imaging method of choice for image-guided neurosurgical operations. However, to be ready for its prime time in the operating room (OR), utilization of MRI in the OR requires development of better techniques for image-guided navigation, as well as interactive real-time teleradiologic methods that will allow tele-collaboration between the surgeon and the radiologist. This presentation describes our work in progress toward achievement of teleradiology in the OR.

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A novel illudane sesquiterpene antibiotic (1) with activity against methicillin-resistant Staphylococcus aureus (MRSA), has been isolated. Its MIC against MRSA was found to be 16 micrograms/mL. It also shows L-1210 cytotoxicity with an IC50 of 10-15 micrograms/mL.

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RATIONALE AND OBJECTIVES: The authors evaluated the diagnostic accuracy of viewing computed tomographic (CT) scans as film versus soft-copy images at a workstation. METHODS: Receiver operating characteristic analysis of the interpretation of 202 CT scans (103 were normal, 99 were abnormal) by five neuroradiologists was performed. Abnormal images contained high- or low-attenuation intraaxial lesions or extraaxial fluid (subdural, subarachnoid, or epidural hemorrhage). Hard copies were read on a standard light box, and digital images were examined at a 1,024 x 1,250 workstation. Lesion location and type and confidence ratings were recorded on a worksheet. RESULTS: There were no statistically significant differences in diagnostic accuracy between the two display modes. Reader performance was slightly better with the workstation in the assessment of low-attenuation lesions. CONCLUSION: Diagnostic accuracy is similar for CT scans displayed at a workstation and those displayed as hard copy in the assessment of subtle intra- and extraaxial brain lesions.

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