Persistent Descending Mesocolon as a Risk Factor of Laparoscopic Surgery for Colorectal Cancer: A Single Institution Experience

The objectives of this study are to clarify the significance of persistent descending mesocolon (PDM), a kind of intestinal malrotation, in laparoscopic colorectal surgery and present potentially useful preoperative diagnostic methods for PDM. Although several risk factors for laparoscopic colorectal surgery have been convincingly reported, the impact of PDM on laparoscopic surgery for colorectal cancer remains less studied. This was an observational study with a retrospective analysis. A consecutive 110 patients undergoing laparoscopic colorectal surgery for colorectal cancer were included. To identify risk factors for operative time of laparoscopic surgery for colorectal cancer, we examined age, sex, body mass index, American Society of Anesthesiologists Performance Status score, tumor location, depth of tumor invasion, lymph node metastasis, and PDM as potential risk factors. For identification of appropriate preoperative diagnostic imaging, we reviewed three-dimensional vessel images reconstructed from computed tomographic slice data of all patients. During the study period, no effective pre- or intraoperative diagnoses of PDM were achieved. A total of 4 patients were diagnosed with PDM. Sex (P = 0.0032); tumor location (P = 0.0044); lymph node metastasis (P = 0.022); and PDM (P = 0.0007) were identified as risk factors based on multivariate analysis. A ventrally branched left colic artery visualized by three-dimensional imaging appeared to be a highly specific feature of PDM. Laparoscopic surgery for colorectal cancer with PDM was difficult without the recognition of PDM. PDM was well-defined preoperatively using three-dimensional vessels images reconstructed from computed tomographic slice data.

Tracing magnetic field with synchrotron polarization gradients: parameter study

ABSTRACT We employ synthetic observations obtained with magnetohydrodynamic simulations to study how to trace the distribution of turbulent magnetic fields using the synchrotron polarization gradient techniques suggested by Lazarian & Yuen. Both synchrotron polarization gradients and its derivative gradients with regard to the squared wavelength λ2 are used to explore the probing ability of the technique in magnetic fields from sub- to super-Alfvénic turbulence. We focus on studies that involve multifrequency measurements in the presence of strong Faraday rotation and show the ways of how to recover the projected mean magnetic fields in the plane of the sky and the local magnetic fields within a tomographic slice. We conclude that the new techniques can successfully reconstruct the 3D magnetic field within our Milky Way and other galaxies. This paper opens an avenue for applying our new techniques to a large number of data cubes such as those from the Low-Frequency Array for radio astronomy and the Square Kilometre Array.

Regional Cerebral Blood Flow in Patients with Affective Disorders

Regional cerebral blood flow at rest was measured in 38 patients with major depressive disorders and 16 controls by SPECT with inhalation of xenon-133. All subjects had been withdrawn from medication. The mean hemispheric cerebral blood flow was not statistically different between the controls and the different subgroups of depressed patients defined either by biological markers or clinical characteristics. However, the predominantly cortical blood flow, measured on the outer cerebral rim of the third tomographic slice, was significantly lower on the left hemisphere in bipolar patients when compared with normals and unipolar patients. The same lateralisation was observed in patients with an endogenous depression according to the Newcastle scale.