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121.
Acetabular angles (AAs) and dorsal acetabular rim angles acquired by computed tomographic (CT) imaging have been used to assess patient response to juvenile pubic symphysiodesis surgery. The purpose of this study was to evaluate the effects of patient positioning and slice selection on these angles, and an attempt was made to devise a repeatable method of measuring these angles that would eliminate positioning effects. We found significant variation in AAs with small differences in pelvic tilt and slice selection. Dorsal acetabular rim angles were not affected. As a result of positioning differences from one CT study to the next, every attempt should be made to standardize pelvic tilt, or eliminate its effect on AAs by standardizing gantry angle in relation to an anatomic landmark that will not change over time. The floor of the sacral vertebral canal may be a reasonable landmark for this purpose and deserves further study.  相似文献   
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Objective: Correlate the necropsy diagnosis with the history, diagnostic findings, and clinical course of dyspneic cats with primary lung parenchymal disease. Design: Retrospective study. Setting: Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania. Animals: Client‐owned cats over 6 months of age hospitalized in the Intensive Care Unit (ICU) with a primary problem of respiratory distress that had pulmonary parenchymal disease on thoracic radiographs, and a complete necropsy. Interventions: None. Measurements and main results: Cats included were assigned into 2 groups based on the pulmonary histopathology: inflammatory (n=8) and neoplastic (n=7) disease. No statistical difference was found between the groups with regard to age, body weight, clinical signs, duration of clinical signs, physical examination findings, thoracic radiography, duration of hospitalization, treatment, and outcome. Cats with neoplasia had a statistically higher mean total white blood cell count (26.60 k/μL±10.41) than those with inflammatory lung disease (11.59 k/μL±4.49; P=0.026). Cats with bacterial or viral pulmonary disease had a significantly shorter median duration of illness (5 days, range 1–7 days) than all other cats (30 days, range 7–365 days; P=0.0042). Ultrasound guided pulmonary fine‐needle aspiration (FNA) provided an accurate diagnosis in 5/5 cases. Conclusions: Forty‐seven percent of cats with pulmonary parenchymal disease had neoplasia. The clinical diagnosis was difficult to obtain ante‐mortem; lung FNA appeared to be the most helpful diagnostic tool in these cases.  相似文献   
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Nine cats, from 11 to 17 years of age (mean 13.6 years of age), were diagnosed with a cranial mediastinal cyst. Thoracic radiographs in all cats were characterized by an increased soft tissue opacity in the cranial mediastinum confirmed to be a cyst by ultrasonography or necropsy. Ultrasonographically cysts appeared as an anechoic mass. A low-cellularity clear fluid was obtained on aspiration. The majority of the cats (n = 8) presented for unrelated conditions with no signs of respiratory distress. No treatment for the cyst was pursued except for drainage during ultrasonographic-guided aspiration in several cats. On follow-up of eight cats, none were symptomatic for the cyst from 3-45 months after diagnosis. Mediastinal cyst should be considered when a cranial mediastinal mass is evident radiographically in an older cat. The majority of feline cranial mediastinal cysts are benign with no need for treatment.  相似文献   
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