Clinical experience of rigid bronchoscopy in single center.

BACKGROUND: The aim of this study was to analyze clinical situations requiring rigid bronchoscopy and evaluate usefulness of rigid bronchoscopic intervention in benign or malignant airway disorders. METHODS: We retrospectively reviewed 29 patients who underwent rigid bronchoscopy from November 2007 to February 2011 at St. Paul's Hospital, The Catholic University of Korea School of Medicine. RESULTS: Of the 29 patients, the most frequent underlying etiology was benign stenosis of trachea (n=20). Of those 20 patients, 16 had post-intubation tracheal stenosis (PITS), 2 had tracheal stenosis due to inhalation burn (IBTS) and other 2 had obstructive fibrinous tracheal pseudomembrane (OFTP). Other etiologies were airway malignancy (n=6), endobronchial stenosis due to tuberculosis (n=2), and foreign body (n=1). For treatment, silicone stent insertion was done in 16 cases of PITS and IBTS and mechanical removal was performed in 2 cases of OFTP. In 6 cases of malignant airway obstruction mechanical debulking was performed and silicone stents were inserted additionally in 2 cases. Balloon dilatation and electrocautery were used in 2 cases of endobronchial stenosis due to tuberculosis. In all cases of stent, airway obstructive symptom improved immediately. Granulation tissue formation was the most common complication. CONCLUSION: Tracheal stenosis was most common indication and silicone stenting was most common procedure of rigid bronchoscopy in our center. Rigid bronchoscopic procedures, at least tracheal silicone stenting, should be included in pulmonary medicine fellowship programs because it is a very effective and indispensable method to relieve critical airway obstruction which needs training to learn.

Compact fiber-pigtailed InGaAs photoconductive antenna module for terahertz-wave generation and detection.

We propose a compact fiber-pigtailed InGaAs photoconductive antenna (FPP) module having an effective heat-dissipation solution as well as a module volume of less than 0.7 cc. The heat-dissipation of the FPP modules when using a heat-conductive printed circuit board (PCB) and an aluminium nitride (AlN) submount, without any cooling systems, improve by 40% and 85%, respectively, when compared with a photoconductive antenna chip on a conventional PCB. The AlN submount is superior to those previously reported as a heat-dissipation solution. Terahertz time-domain spectroscopy (THz-TDS) using the FPP module perfectly detects the absorption lines of water vapor in free space and an α-lactose sample.