Hirohisa Kajiwara

New methods of control against postoperative methicillin-resistant Staphylococcus aureus infection.

The incidence of postoperative infections caused by methicillin-resistantStaphylococcus aureus (MRSA) in Japan has been increasing dramatically. In March 1990, we assigned special doctors in infection control (infection control doctor, ICD), and defined comprehensive controls against MRSA infection. A total of 3 536 cases of digestive tract surgery performed at our department were studied during the period between September 1987 and August 1997. We changed the use of antibiotics to prevent postoperative infection. Cefazolin (CEZ) was employed for surgery of the upper digestive tract, including esophagus, stomach, duodenum, and gallbladder. Cefotiam (CTM) was employed for surgery of the lower digestive tract, liver, and pancreas. In esophageal resection, the tracheal tube was extracted during the early postoperative period, and for cervical esophagogastroanastomosis, the autosuture was changed to layer-to-layer anastomosis. We have achieved successful control of postoperative MRSA infection, the incidence having decreased to 0.3% (9/2703). In conclusion, our methods of control against postoperative MRSA infection implies that comprehensive measures of prevention, including the reviewed specification and usage of antibiotics and operation management, have been well implemented. This value is the lowest and the first of any domestic hospital or institute in Japan, suggesting a continued and significant decrease.

Omental cyst: report of a case.

Abstract We report the case of an omental cyst, a rare type of abdominal cystic lesion that is difficult to diagnose preoperatively. A 43-year-old man with no clinical symptoms was admitted to our hospital for investigation of an abdominal cyst detected by ultrasonography (US). We performed diagnostic examinations including US, computed tomography, and magnetic resonance imaging. An omental cyst was diagnosed because of its position and connection to the surrounding tissues. Pathological examination of the surgical specimen revealed endothelial cells on its internal wall and colonies of lymphocytes, confirming a diagnosis of lymphangioma, which is the most common type of omental cyst.

Bilirubin Calculi Crushing by Laser Irradiation at a Molecular Oscillating Region Wavelength Based on Infrared Absorption Spectrum Analysis Using a Free-Electron Laser: An Experimental Study

Abstract We investigated a new laser technique of crushing bilirubin calculi, our aim being to crush calculi in isolation using a minimally invasive procedure. Infrared absorption spectrum analysis of the bilirubin calculi was conducted, revealing maximum absorption spectrum at a wavelength of the C=O stretching vibration of ester binding that exists within the molecular structure of bilirubin calcium. As an experiment to crush calculi using the free-electron laser, we set the laser at the effective irradiation wavelength of ester binding, and conducted noncontact irradiation of the bilirubin calculi. The calculi began to slowly ablate until the irradiated site had been completely obliterated after 20 s of irradiation. Moreover, absorption spectrum analysis of the irradiated site, from a comparison of absorption peak ratios, revealed that absorption peak intensities decreased over time at the absorption wavelength of ester binding. These findings suggest that irradiation of molecular oscillating region wavelengths peculiar to calculi based on infrared absorption spectrum analysis results in the gradual crushing of calculi in isolation by breaking down their molecular structure.