Temperature dependence of a Raman CO2 densimeter from 23 degrees C to 200 degrees C and 7.2 to 248.7 MPa : Evaluation of density underestimation by laser heating

Unintended local temperature enhancement by excitation laser might change Raman spectral features and potentially lead to misinterpretation of the data. To evaluate robustness of Raman CO2 densimeters in the presence of laser heating, we investigate the relation between temperature (T, degrees C), density (rho, g/cm(3)), and Fermi diad split (Delta, cm(-1)) using a high-pressure optical cell at 23 degrees C to 200 degrees C and 7.2-248.7 MPa. Results indicate that Delta decreases concomitantly with increasing temperature for a constant density in all density regions investigated. This result suggests that the density estimated based on Delta might be underestimated if the fluid is heated locally by the laser. Combining results of earlier studies with those of the present study indicates that the temperature dependence of Delta (|( partial differential Delta/ partial differential T)(rho)|) has a maximum value around 0.6-0.7 g/cm(3). Consequently, at very high densities such as 1.1-1.2 g/cm(3), |( partial differential Delta/ partial differential T)(rho)| is small. Thus, Delta at such densities is less affected by laser heating. However, at densities below approximately 0.7 g/cm(3), although |( partial differential Delta/ partial differential T)(rho)| becomes smaller at lower densities, the relative density decrease becomes larger even for a small density decrease because the density itself becomes smaller. Therefore, at such densities, a density decrease of more than 10% was observed for some fluid inclusions, even at typical laser powers for inclusion analysis. Finally, to accurately estimate the density even in the presence of laser heating, we show that it is effective to estimate the intercept Delta from the correlation between Delta and laser power and substitute it into Delta-rho relations

Laparoscopic Resection of an Intra-Abdominal Esophageal Duplication Cyst: A Case Report and Literature Review

Duplication of the alimentary tract is a rare congenital malformation that occurs most often in the abdominal region, whereas esophageal duplication cyst develops typically in the thoracic region but occasionally in the neck and abdominal regions. Esophageal duplication cyst is usually diagnosed in early childhood because of symptoms related to bleeding, infection, and displacement of tissue surrounding the lesion. We recently encountered a rare adult case of esophageal duplication cyst in the abdominal esophagus. A 50-year-old man underwent gastroscopy, endoscopic ultrasonography, computed tomography, and magnetic resonance imaging to investigate epigastric pain and dysphagia that started 3 months earlier. Imaging findings suggested esophageal duplication cyst, and the patient underwent laparoscopic resection followed by intraoperative esophagoscopy to reconstruct the esophagus safely and effectively. Histopathological examination of the resected specimen revealed two layers of smooth muscle in the cystic wall, confirming the diagnosis of esophageal duplication cyst