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Conventional color flow processing is associated with a high degree of operator dependence, often requiring the careful tuning of clutter filters and priority encoding to optimize the display and accuracy of color flow images. In a companion paper, we introduced a novel framework to adapt color flow processing based on local measurements of backscatter spatial coherence. Through simulation studies, the adaptive selection of clutter filters using coherence image quality characterization was demonstrated as a means to dynamically suppress weakly-coherent clutter while preserving coherent flow signal in order to reduce velocity estimation bias. In this study, we extend previous work to evaluate the application of coherence-adaptive clutter filtering (CACF) on experimental data acquired from both phantom and in vivo liver and fetal vessels. In phantom experiments with clutter-generating tissue, CACF was shown to increase the dynamic range of velocity estimates and decrease bias and artifact from flash and thermal noise relative to conventional color flow processing. Under in vivo conditions, such properties allowed for the direct visualization of vessels that would have otherwise required fine-tuning of filter cutoff and priority thresholds with conventional processing. These advantages are presented alongside various failure modes identified in CACF as well as discussions of solutions to mitigate such limitations.

The appropriate selection of a clutter filter is critical for ensuring the accuracy of velocity estimates in ultrasound color flow imaging. Given the complex spatio-temporal dynamics of flow signal and clutter, however, the manual selection of filters can be a significant challenge, increasing the risk for bias and variance introduced by the removal of flow signal and/or poor clutter suppression. We propose a novel framework to adaptively select clutter filter settings based on color flow image quality feedback derived from the spatial coherence of ultrasonic backscatter. This framework seeks to relax assumptions of clutter magnitude and velocity that are traditionally required in existing adaptive filtering methods to generalize clutter filtering to a wider range of clinically-relevant color flow imaging conditions. In this study, the relationship between color flow velocity estimation error and the spatial coherence of clutter filtered channel signals was investigated in Field II simulations for a wide range of flow and clutter conditions. This relationship was leveraged in a basic implementation of coherence-adaptive clutter filtering (CACF) designed to dynamically adapt clutter filters at each imaging pixel and frame based on local measurements of spatial coherence. In simulation studies with known scatterer and clutter motion, CACF was demonstrated to reduce velocity estimation bias while maintaining variance on par with conventional filtering.

Objectives: Ultrasound users are advised to observe the ALARA (as low as reasonably achievable) principle, but studies have shown that most do not monitor acoustic output metrics. We developed an adaptive ultrasound method that could suggest acoustic output levels based on real-time image quality feedback using lag-one coherence (LOC)., Methods: Lag-one coherence as a function of the mechanical index (MI) was assessed in 35 healthy volunteers in their second trimester of pregnancy. While imaging the placenta or the fetal abdomen, the system swept through 16 MI values ranging from 0.15 to 1.20. The LOC-versus-MI data were fit with a sigmoid curve, and the ALARA MI was selected as the point at which the fit reached 98% of its maximum., Results: In this study, the ALARA MI values were between 0.35 and 1.03, depending on the acoustic window. Compared to a default MI of 0.8, the pilot acquisitions suggested a lower ALARA MI 80% of the time. The contrast, contrast-to-noise ratio, generalized contrast-to-noise ratio, and LOC all followed sigmoidal trends with an increasing MI. The R 2 of the fit was statistically significantly greater for LOC than the other metrics (P < .017)., Conclusions: These results suggest that maximum image quality can be achieved with acoustic output levels lower than the US Food and Drug Administration limits in many cases, and an automated tool could be used in real time to find the ALARA MI for specific imaging conditions. Our results support the feasibility of an automated, LOC-based implementation of the ALARA principle for obstetric ultrasound., (© 2020 American Institute of Ultrasound in Medicine.)

Mycoplasma bovis is 1 of several bacterial pathogens associated with pneumonia in cattle. Its role in pneumonia of free-ranging ungulates has not been established. Over a 3-month period in early 2019, »60 free-ranging pronghorn with signs of respiratory disease died in northeast Wyoming, USA. A consistent finding in submitted carcasses was severe fibrinosuppurative pleuropneumonia and detection of M. bovis by PCR and immunohistochemical analysis. Multilocus sequence typing of isolates from 4 animals revealed that all have a deletion in 1 of the target genes, adh-1. A retrospective survey by PCR and immunohistochemical analysis of paraffin-embedded lung from 20 pronghorn that died with and without pneumonia during 2007-2018 yielded negative results. These findings indicate that a distinct strain of M. bovis was associated with fatal pneumonia in this group of pronghorn.

The genus Neorickettsia includes obligate, intracellular bacteria responsible for diseases including Potomac horse fever caused by Neorickettsia risticii and salmon poisoning disease (SPD) caused by Neorickettsia helminthoeca . The Stellanchasmus falcatus (SF) agent is a member of this genus previously associated only with mild clinical signs in dogs. Between 2013 and 2016, 3 dogs in Washington State (USA) presented with disease suggestive of SPD, but N. helminthoeca was not detected by molecular techniques. Clinical signs included depression, anorexia, and diarrhea. Cytologic examination of aspirates supported a diagnosis of granulomatous lymphadenitis with organisms suggestive of Neorickettsia . Dogs either died or were humanely euthanized due to poor response to therapy. Necropsy findings included lymphadenomegaly and hepatomegaly. Histopathology identified granulomatous and lymphoplasmacytic splenitis, lymphadenitis, enteritis, and hepatitis with extensive necrosis. Neorickettsia DNA was detected using genus-specific primers and direct sequencing showed 100% sequence identity to the SF agent in all 3 dogs. This is the first clinicopathologic description of severe disease in dogs attributed to the SF agent. These findings may suggest the emergence of a novel neorickettsial disease in the Pacific Northwest.

Association of Mycoplasma ovipneumoniae with pneumonia in domestic small ruminants has been described in Europe, Asia, and New Zealand but has received less attention in the United States. In 2011, the US Department of Agriculture's National Animal Health Monitoring System detected M. ovipneumoniae shedding in 88% of 453 domestic sheep operations tested in 22 states that accounted for 85.5% of US ewe inventory in 2001. We evaluated factors associated with M. ovipneumoniae infection presence and prevalence, and we compared health, lamb production, and ewe losses in infected and uninfected operations. M. ovipneumoniae detection was more common in larger operations than in smaller operations. Both likelihood of detection (at the operation level) and within-operation prevalence were higher in operations with more open management practices than in operations with more closed management practices. M. ovipneumoniae-positive operations showed significantly lower lambing rates and lower rates of lamb survival to weaning after accounting for differences in operation size and management practice. While its effect on any single rate was not particularly large, in aggregate we estimated that M. ovipneumoniae presence was associated with an approximately 4.3% reduction in annual lamb production., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We report 5 cases of coccidioidomycosis in animals that were acquired within Washington, USA, and provide further evidence for the environmental endemicity of Coccidioides immitis within the state. Veterinarians should consider coccidioidomycosis in animals with compatible clinical signs that reside in, or have traveled to, south central Washington.

In this study, we evaluate the clinical utility of fetal short-lag spatial coherence (SLSC) imaging. Previous work has documented significant improvements in image quality with fetal SLSC imaging as quantified by measurements of contrast and contrast-to-noise ratio (CNR). The objective of this study was to examine whether this improved technical efficacy is indicative of the clinical utility of SLSC imaging. Eighteen healthy volunteers in their first and second trimesters of pregnancy were scanned using a modified Siemens SC2000 clinical scanner. Raw channel data were acquired for routinely examined fetal organs and used to generate fully matched raw and post-processed harmonic B-mode and SLSC image sequences, which were subsequently optimized for dynamic range and other imaging parameters by a blinded sonographer. Optimized videos were reviewed in matched B-mode and SLSC pairs by three blinded clinicians who scored each video based on overall quality, target conspicuity and border definition. SLSC imaging was highly favored over conventional imaging with SLSC scoring equal to (28.2 ± 10.5%) or higher than (63.9 ± 12.9%) B-mode for video pairs across all examined structures and processing conditions. Multivariate modeling revealed that SLSC imaging is a significant predictor of improved image quality with p ≤ 0.002. Expert-user scores for image quality support the application of SLSC in fetal ultrasound imaging., (Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.)

Two novel and distinct Brucella strains were recovered from 5 of 10 adult, sex undetermined, captive waxy tree frogs ( Phyllomedusa sauvagii) and two of five adult, sex undetermined, captive Colorado river toads ( Incilius alvarius) held in a zoologic collection with clinical and pathologic findings of bacterial disease. These amphibians originated from three separate private breeding facilities over several years and exhibited disease 9-49 mo following release from quarantine. Common presenting signs were vague but included focal abscessation, weight loss, change in coloration, anorexia, and decreased perching. Two waxy tree frogs and one Colorado river toad recovered with supportive care and antimicrobial treatment based on susceptibility testing. Microgranulomatosis, subcutaneous and renal abscessation, femoral osteomyelitis, and multicentric infection were the most common histologic findings. The organisms were identified antemortem in samples from subcutaneous abscesses, cloaca, and skin and from a variety of organ systems postmortem, and demonstrated a consistent susceptibility pattern. Initial isolates were misidentified as Ochrobactrum anthropi. Polymerase chain reaction and sequencing of the 16S rRNA gene identified the two organisms as novel Brucella strains similar to Brucella inopinata-like sp. and other novel organisms within the emerging "BO clade." Brucella strain oaks (isolated from waxy tree frogs) and Brucella strain leathers (isolated from Colorado river toads) differed from each other by 16 of 571 base pairs in a region of chromosome 2, and did not closely match any previous GenBank entries. This report describes the clinicopathologic features of infection by these bacteria in two amphibian species and expands the range of novel Brucella organisms from amphibian reservoirs.

A 25-yr-old Diana monkey (Cercopithecus diana) with a 1.5-yr history of chronic colitis and diarrhea was found to have disseminated granulomatous disease with intralesional acid fast bacilli. Bacilli were identified as Mycobacterium genavense by polymerase chain reaction, sequencing of the 16S-23S ribosomal RNA intergenic spacer (ITS) gene, and mycolic acid analysis by high-performance liquid chromatography. Mycobacterium genavense is a common cause of mycobacteriosis in free-ranging and captive birds. In addition, recognition of opportunistic infection in human immunodeficiency virus-positive patients is increasing. Disease manifestations of M. genavense are similar to Mycobacterium avium complex (MAC) and include fever, wasting, and diarrhea with disseminated disease. Similar clinical signs and lesions were observed in this monkey. Mycobacterium genavense should be considered as a differential for disseminated mycobacterial disease in nonhuman primates as this agent can mimic MAC and related mycobacteria.

Four pigs, three with focal infarctions in the apical intraventricular septum (IVS) and/or left ventricular free wall (LVFW), were imaged with an intracardiac echocardiography (ICE) transducer. Custom beam sequences were used to excite the myocardium with focused acoustic radiation force (ARF) impulses and image the subsequent tissue response. Tissue displacement in response to the ARF excitation was calculated with a phase-based estimator, and transverse wave magnitude and velocity were each estimated at every depth. The excitation sequence was repeated rapidly, either in the same location to generate 40 Hz M-modes at a single steering angle, or with a modulated steering angle to synthesize 2-D displacement magnitude and shear wave velocity images at 17 points in the cardiac cycle. Both types of images were acquired from various views in the right and left ventricles, in and out of infarcted regions. In all animals, acoustic radiation force impulse (ARFI) and shear wave elasticity imaging (SWEI) estimates indicated diastolic relaxation and systolic contraction in noninfarcted tissues. The M-mode sequences showed high beat-to-beat spatio-temporal repeatability of the measurements for each imaging plane. In views of noninfarcted tissue in the diseased animals, no significant elastic remodeling was indicated when compared with the control. Where available, views of infarcted tissue were compared with similar views from the control animal. In views of the LVFW, the infarcted tissue presented as stiff and non-contractile compared with the control. In a view of the IVS, no significant difference was seen between infarcted and healthy tissue, whereas in another view, a heterogeneous infarction was seen to be presenting itself as non-contractile in systole.

A 5-year-old female spayed Shetland Sheepdog Mix dog was evaluated for a history of recent seizure activity, progressive hind limb ataxia, polyuria, and polydipsia and no history of gastrointestinal signs. Physical examination findings included conscious proprioceptive deficits, ataxia, and anterior uveitis along with a hypermature cataract in the right eye. Results of a CBC, serum biochemical profile, urinalysis, and computed tomography scan of the brain were unremarkable. Cerebrospinal fluid (CSF) analysis revealed marked eosinophilic pleocytosis and rare organisms consistent with Prototheca spp within neutrophils and macrophages. On postmortem histologic examination, mononuclear inflammation and numerous intralesional algal organisms, similar to those seen on the cytologic preparation of CSF, were found in the brain, eyes, kidneys, and heart. Abnormalities were not detected on gross and histologic examination of the gastrointestinal tract. Cultures of CSF and subdural/olfactory bulb, but not intestinal tract, yielded growth of Prototheca spp, and PCR analysis and DNA sequencing confirmed the organism as Prototheca zopfii genotype 2. We have reported a rare case of disseminated protothecosis that was diagnosed by evaluation of CSF in a dog presented with neurologic signs and no overt enteric disease. Protothecosis should be considered as a rare cause of seizures, even in the absence of obvious enteric signs, and should be included in the differential diagnosis of eosinophilic pleocytosis., (© 2012 American Society for Veterinary Clinical Pathology.)

A freshwater angelfish (Pterophyllum scalare) hatchery experienced variable levels of emaciation, poor growth rates, swollen coelomic cavities, anorexia, listlessness, and increased mortality within their fish. Multiple chemotherapeutic trials had been attempted without success. In affected fish, large numbers of protozoa were identified both histologically and ultrastructurally associated with the gastric mucosa. The youngest cohort of parasitized fish was the most severely affected and demonstrated the greatest morbidity and mortality. The protozoa were morphologically most consistent with Cryptosporidium. All of the protozoan life stages were identified ultrastructurally and protozoal genomic DNA was isolated from parasitized tissue viscera and sequenced. Histological, ultrastructural, genetic, and phylogenetic analyses confirmed this protozoal organism to be a novel species of Cryptosporidium.

An adult male, wild-caught fairy bluebird (Irena puella) was evaluated after diagnosis of hepatic mycobacterial disease in a bird sharing the same quarantine space. Initial results did not reveal leukocytosis or acid-fast organisms in a liver biopsy. However, Mycobacterium avium was found in the liver via polymerase chain reaction (PCR). After euthanasia, acid-fast stains remained negative in the liver, although PCR was positive and M. avium complex (identified by high-performance liquid chromatography) was isolated from the liver. PCR could offer a relatively sensitive and rapid diagnostic test in the investigation of mycobacterial disease in avian patients.

Seven psittacine birds and a toucan (Ramphastos toco) were diagnosed as infected with Coxiella-like bacteria, based on polymerase chain reaction and bacterial 16S rRNA gene sequence obtained from each bird's liver tissue. Most of the birds exhibited lethargy and weakness for several days prior to death. Gross lesions included mild to moderate emaciation and severely enlarged and mottled pale livers and spleens. Microscopically, there was multifocal necrosis of hepatocytes with infiltration of a mixed population of inflammatory cells, including lymphocytes, heterophils, plasma cells, and macrophages randomly scattered throughout in most birds. In several birds within the macrophages there were vacuoles containing basophilic small cocco-bacilli organisms measuring about 0.5-1 microm. The spleens had increased numbers of mononuclear phagocytic system cells, some of which had vacuoles that contained similar organisms, as observed in the liver. There was inflammation in the epicardium and endocardium, interstitium of the lungs, kidney, adrenal and thyroid glands, lamina propria of the intestine, and in occasional birds in the brain, bursa of Fabricius, and bone marrow associated with similar organisms in the macrophages. Transmission electron microscopy of the liver and lungs in most birds and in the thyroid glands of one bird revealed pleomorphic round to elongated bacteria measuring about 0.45 microm in diameter and more than 1.0 microm in length. Most of these organisms contained a peripheral zone of loosely arranged electron dense material that was located immediately beneath a trilaminar membrane. Occasional organisms contained nucleoids. This is the first documentation of disease presumptively associated with Coxiella-like bacteria in birds.

Three Swainson's Blue Mountain Rainbow Lorikeets (Trichoglossus haematodus moluccanus), ranging from 6 to 8 months of age, presented with lethargy, emaciation, and progressive neurologic signs. The first one died 24 hours after the onset of clinical signs, and the other two were euthanized 10 to 14 days after the onset of progressive neurologic disease. Clinical signs in these lorikeets included head pressing, hemiparesis, seizures, obtunded mentation, weakness, and lethargy. Two of the lorikeets had hepatomegaly, and one had splenomegaly on gross examination. Histopathology revealed disseminated microgranulomas in the liver, spleen, and brain, and lymphohistocytic perivascular encephalitis and cephalic vasculitis. Electron microscopic examination of macrophages in brain lesions revealed spherical to rod-shaped prokaryotic organisms with a trilaminar cell wall. Molecular analysis revealed a novel species of Coxiella. This is believed to be the first report of a Coxiella sp. causing disease in a lorikeet.

Mycobacterium haemophilum, a nontuberculous mycobacterium, is a pathogen in immunocompromised human patients. We report a case of M haemophilum-induced granuloma in the spinal cord of an American Bison (Bison bison). M haemophilum infection was diagnosed by sequencing a portion of the 16 S ribosomal DNA and comparing the amplicon sequence with sequences in GenBank.

Waddlia chondrophila is a little-known intracellular organism belonging to the order Chlamydiales that has twice been isolated from aborted bovine fetuses. To initiate an investigation of the possibility that W. chondrophila may be an abortifacient pathogen, a serologic test was developed and used to screen bovine sera that were submitted to the Washington Animal Disease Diagnostic Laboratory (Pullman, WA). A highly significant statistical association (P < 0.00001) was observed when comparing antibody titers in cows that had aborted with those in other classes of cattle. Although this result is consistent with the possibility that infection with W. chondrophila may be a cause of bovine abortion, it is also possible that seroprevalence simply increases with age or that exposure rates differ between cows and other classes of cattle. Future serologic studies should specifically compare antibody titers between aborting cows and carefully matched nonaborting cohorts.

The sensitivity of the agar gel immunodiffusion (AGID) test for the detection of antibody to caprine arthritis-encephalitis virus (CAEV) was investigated with CAEV or ovine progressive pneumonia virus (OPPV) as the source of antigen. A total of 218 goat serum specimens were tested for anti-CAEV antibody by AGID and immunoprecipitation of [35S]methionine-labeled CAEV. In comparison with that of immunoprecipitation, the sensitivity of the CAEV AGID test was 0.91, and that of the OPPV AGID test was 0.56. The AGID test with either antigen was 100% specific. The lower sensitivity of the OPPV AGID test in detecting caprine antibody to CAEV indicates that OPPV antigen is of limited value for use in CAEV diagnosis and control programs.