Narrowing the Differential Diagnosis of Cystic Lesions in Smokers with Expiratory CT Acquisition Using the Cyst-Airway Communication Hypothesis.

The aim of this study was to assess percentage respiratory changes (δ) in the size of pulmonary cysts of different smoking-related etiologies. Retrospectively, we measured the cystic lesions due to histopathological-confirmed honeycombing from interstitial pulmonary fibrosis, pulmonary Langerhans cell histiocytosis (PLCH), and paraseptal emphysema, using paired inspiratory and expiratory CT scans. In a sample of 72 patients and 216 lesions, the mean diameter of PLCH and honeycombing decreased during expiration (PLCH, δ = 60.9%; p = 0.001; honeycombing, δ = 47.5%; p = 0.014). Conversely, paraseptal emphysema did not show any changes (δ = 5.2%; p = 0.34). In summary, our results demonstrated that cysts in smokers with PLCH and honeycombing fibrosis get smaller during expiratory CT scans, whereas the size of cystic-like lesions due to paraseptal emphysema and bullae tend to remain constant during respiratory cycles. These results support the hypothesis of cyst-airway communication in some cystic diseases, which could assist in the differential diagnosis in smoking-related lung diseases.

Pulmonary Acinus: Understanding the Computed Tomography Findings from an Acinar Perspective.

The lung acinus is the most distal portion of the airway responsible for the gas exchange. The normal acini are not visible on conventional computed tomography (CT), but the advent of micro-CT improved the understanding of the microarchitecture of healthy acini. The comprehension of the acinar architecture is pivotal for the understanding of CT findings of diseases that involve the acini. Centriacinar emphysema, for example, presents as round areas of low attenuation due to the destruction of the most central acini with compensatory enlargement of proximal acini due to alveolar wall destruction. In pulmonary fibrosis, intralobular septal fibrosis manifests as acinar wall thickening with an overlap of acinar collapse and compensatory dilation of surrounding acini constituting the cystic disease typical of the usual interstitial pneumonia pattern. This is a state-of-the-art review to describe the acinar structure from the micro-CT perspective and display how the comprehension of the acinar structure can aid in the interpretation of its microarchitecture disruption on conventional CT.

Reproducibility of abdominal fat assessment by ultrasound and computed tomography.

OBJECTIVE: To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments. MATERIALS AND METHODS: Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the anthropometric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT. RESULTS: Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71. CONCLUSION: In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility.

OBJETIVO: Testar a precisão e a reprodutibilidade da ultrassonografia (US) e da tomografia computadorizada (TC) para a quantificação da gordura abdominal, em correlação com as avaliações antropométricas e clinicolaboratoriais. MATERIAIS E MÉTODOS: Foram determinadas, por meio da US e da TC, as espessuras subcutâneas e intra-abdominais em 101 indivíduos, sendo 39 homens (38,6%) e 62 mulheres (61,4%), com idade média de 66,3 anos (60-80 anos). Os dados obtidos pela US foram correlacionados com os parâmetros antropométricos, clinicolaboratoriais e com as áreas abdominais medidas pela TC. RESULTADOS: A espessura da gordura intra-abdominal foi a variável que obteve maior coeficiente de correlação com as áreas adiposas abdominais. A TC mostrou maior reprodutibilidade nas mensurações da gordura abdominal, apresentando maior taxa de concordância intraexaminador e interexaminador em comparação com a US. Observou-se índice de correlação de 71% entre a US e a TC. CONCLUSÃO: Houve maior concordância intraexaminador e interexaminador na avaliação da gordura abdominal por TC, comparativamente à US, porém ambos os métodos mostraram alta precisão e boa reprodutibilidade.

Reproducibility of abdominal fat assessment by ultrasound and computed tomography / Reprodutibilidade da avaliação da gordura abdominal pela ultrassonografia e tomografia computadorizada

Abstract Objective: To test the accuracy and reproducibility of ultrasound and computed tomography (CT) for the quantification of abdominal fat in correlation with the anthropometric, clinical, and biochemical assessments. Materials and Methods: Using ultrasound and CT, we determined the thickness of subcutaneous and intra-abdominal fat in 101 subjects-of whom 39 (38.6%) were men and 62 (61.4%) were women-with a mean age of 66.3 years (60-80 years). The ultrasound data were correlated with the anthropometric, clinical, and biochemical parameters, as well as with the areas measured by abdominal CT. Results: Intra-abdominal thickness was the variable for which the correlation with the areas of abdominal fat was strongest (i.e., the correlation coefficient was highest). We also tested the reproducibility of ultrasound and CT for the assessment of abdominal fat and found that CT measurements of abdominal fat showed greater reproducibility, having higher intraobserver and interobserver reliability than had the ultrasound measurements. There was a significant correlation between ultrasound and CT, with a correlation coefficient of 0.71. Conclusion: In the assessment of abdominal fat, the intraobserver and interobserver reliability were greater for CT than for ultrasound, although both methods showed high accuracy and good reproducibility.

Resumo Objetivo: Testar a precisão e a reprodutibilidade da ultrassonografia (US) e da tomografia computadorizada (TC) para a quantificação da gordura abdominal, em correlação com as avaliações antropométricas e clinicolaboratoriais. Materiais e Métodos: Foram determinadas, por meio da US e da TC, as espessuras subcutâneas e intra-abdominais em 101 indivíduos, sendo 39 homens (38,6%) e 62 mulheres (61,4%), com idade média de 66,3 anos (60-80 anos). Os dados obtidos pela US foram correlacionados com os parâmetros antropométricos, clinicolaboratoriais e com as áreas abdominais medidas pela TC. Resultados: A espessura da gordura intra-abdominal foi a variável que obteve maior coeficiente de correlação com as áreas adiposas abdominais. A TC mostrou maior reprodutibilidade nas mensurações da gordura abdominal, apresentando maior taxa de concordância intraexaminador e interexaminador em comparação com a US. Observou-se índice de correlação de 71% entre a US e a TC. Conclusão: Houve maior concordância intraexaminador e interexaminador na avaliação da gordura abdominal por TC, comparativamente à US, porém ambos os métodos mostraram alta precisão e boa reprodutibilidade.

Training for laparoendoscopic single-site surgery (LESS).

BACKGROUND: Laparoendoscopic single-site surgery (LESS) is a laparoscopic surgery in which a single small incision is made, associated with the use of a special device (single-port), or several small incisions grouped in one location (single-incision) are made, through which the laparoscopic trocars are inserted. The incision is made in the abdomen, preferably in the umbilicus. Certain peculiarities are noted in this approach, such as the difficulty, and sometimes the impossibility, of centering the image, the need to move both the camera and instruments together, requiring even more delicate and precise movements than in laparoscopy. Since information on training for LESS is scarce in the current literature, the authors report their experience with five different cases of this nature, performed in two porcine models, and then discuss a training plan for LESS. METHODS: Five LESS procedures were performed in two pigs using different training techniques: two (one single-port and one single-incision) transumbilical laparoscopic cholecystectomies; one right-sided single-incision laparoscopic radical nephrectomy; one single-incision transumbilical laparoscopic radical nephrectomy; and one single-port transumbilical laparoscopic nephrectomy. DISCUSSION: Different from what was observed in the transition from open surgery to laparoscopy, the Halstedian model should not be used in the teaching of LESS since this procedure requires that professionals partner together, thus requiring not only the training of surgeons, but of the whole team. CONCLUSION: LESS procedures are feasible and considered as further refinements in laparoscopic techniques. However, the peculiarities and difficulties inherent in these procedures require a specific training program combining theory and practice. The authors believe that this training is essential to achieve proficiency levels before the technique can be tried on human subjects.