Background. We have been developing endobronchial ultrasonography (EBUS) since 1994, and to date have examined 1500 cases and reported its usefulness. The most important indication, which can only be achieved with this method, is determination of the depth of tumor invasion of tracheobronchial lesions. We have reported on normal laminar layer images of the bronchial wall and comparisons between EBUS images and histopathologic findings. Method. In this report, we report laminar structures of the bronchial wall as visualized by a 30 MHz probe and the usefulness of 3D EBUS. Results. Compared with the laminar structures of the bronchial wall visualized by a 20 MHz probe, the marginal echoes of laminar structures were two-thirds thinner using a 30 MHz probe. Thus the 2nd and 4th layers were thicker and the 30 MHz equipment was useful to determine the depth of tumor invasion of tracheobronchial lesions by 30 MHz. The linear images of the bronchial wall by 3D EBUS were the same as the histopathologic findings.

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Background. The development of fluorescence bronchoscopy has made it possible to localize early hilar lung cancer and squamous dysplasia. Purpose. We assessed the usefulness of fluorescence bronchoscopy (LIFE-Lung system) for detection of early hilar lung cancer and squamous dysplasia. Materials and Methods. From October 1997, to April 2001, a total of 236 patients were examined with fluorescence bronchoscopy (LIFE-Lung system), and 565 biopsy specimens were obtained. Furthermore, we periodically followed up localized dysplasias and assessed histological changes. Results. Sixteen early hilar lung cancers, including 4 carcinomas in situ, and 124 dysplasias were detected. Among them, one carcinoma in situ and 32 dysplasias were found only with LIFE. The sensitivity of biopsy proved early lung cancer or dysplasia detected by white-light bronchoscopy alone was 65.0%, with the addition of LIFE, the sensitivity was significantly increased to 88.6% (p<0.0001). Of 74 dysplasias, 2 dysplasias developed to squamous cell carcinoma. Thirty-one dysplasias maintained dysplasias, and 38 dysplasias regressed to bronchitis or normal bronchial epithelium. Conclusion. LIFE was useful for the detection of early hilar lung cancer and squamous dysplasia. Because there were some dysplasias which progressed to cancer or which maintained dysplasia during the follow-up period, it was thought that the follow-up of localized dysplasias was important.

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Purpose. The GaN-based ultraviolet laser diode (UV-LD), which has recently became commercially available, was used to study the autofluorescence (AF) of human bronchial tissue. The conventional AF measurement system uses a large excitation light source, and the measured data have problems associated with the intermixing of the excitation source and the AF signal. The wavelength of the UV-LD is much shorter than that of the He-Cd laser which is employed for the LIFE system, and the AF measurement is performed without interference of the excitation light using the UV-LD. AF data were compared with those obtained using the He-Cd laser. Method. The spectroscopic analysis of the AF was performed for 13 resected specimens of the human bronchus using the UV-LD. The relationship between the origin of the AF signal and the histopathological structure was also studied. Result. The AF characteristics were similar to those obtained using the He-Cd laser or the xenon lamp. Blue AF, the peak wavelength of which was at around 483 nm was additionally observed from normal tissues. The spatial distribution of the AF signal intensity revealed that a strong AF signal obtained from the region where the high density of the elastin was confirmed. Conclusion. The AF measurement in a wide wavelength region can be easily performed by using the UV-LD as the excitation light source.

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Purpose. We studied the results of tracheobronchoplasty for benign tracheobronchial stenotic lesions. Methods. We report the results of surgical treatment of 8 patients (7 women, 1 man, mean age 40 years old) who underwent tracheobronchoplasty for benign tracheobronchial stenosis between 1991 and 2001. Operative indications were decided based on exertional dyspnea or pinhole-like stenosis or obstruction recognized bronchofiberscopically. The etiology of bronchial stenosis was tuberculosis (4 cases), necrotizing sarcoid granulomatosis (1 case) and postintubation (3 cases). The areas of stenosis were the left main bronchus (3 cases) and the left upper lobe bronchus (1 case) in patients with tuberculous stenosis, right main bronchus and truncus intermedius (1 case) in the patient with necrotizing sarcoid granulomatosis and the upper trachea (3 cases) in patients with post-intubation stenosis. The operative approach was posterolateral thoracotomy in the patients with tuberculosis and necrotizing sarcoid granulomatosis, and collar incision in the patients with postintubation stenosis. Operative procedures were left sleeve upper lobectomy (1 case),left upper lobe bronchus resection and end to end anastomosis (1 case),left main bronchus resection and end-to-end anstomosis (2 cases), right sleeve middle and lower lobectomy (1 case) and tracheal resection and end-to-end anastomosis (3 cases) with absorbable monofilament thread. Operative times were 288 minutes (mean) in tuberculosis, 252 minutes in necro-tizing sarcoid granulomatosis, and 124 minutes (mean) in postintubation cases. Operative bleeding was 416 ml (mean) in tuberculosis, 385 ml in necrotizing sarcoid granulomatosis, and 97 ml (mean) in postintubation cases. Results. There were no complications or recurrence of stenotic lesions in any of the patients in the observed period. Conclusion. These results suggest that tracheobronchoplasty is a safe and useful operative procedure for benign stenotic lesions.

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Background. We report two cases of tracheal stenting using a percutaneous cardiopulmonary support system (PCPS) due to central airway obstruction by malignant tumor. Purpose. Necessity and indication of tracheal stenting for patients with central airway obstruction under PCPS is investigated. Case 1. A 75-year-old man fell into a critical respiratory failure due to airway bleeding during Nd-YAG laser treatment for postoperative recurrent lung cancer. PCPS was started in an emergency, stenting was performed safely as a result. Case 2. A 68-year-old man required mechanical ventilation for tracheal compression because of advanced esophageal cancer. PCPS was started beforehand because it was impossible to ventilate on the occasion of stenting without tracheal tube. Results. Both patients received stenting in stable condition and had no complication. Conclusion. Stenting with the PCPS had the advantages of setting the oxygen concentration at a low level, keeping the patient in a stable condition, and needing no complicated procedure. PCPS should be considered in cases in which respiratory distress or unstable circulatory condition can be predicted at operation.

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Background. Because transbronchial needle aspiration (TBNA) is an easy and safe procedure, its usefulness for the diagnosis of mediastinal lymphadenopathy is established. However we encountered a case of pneumomediastinum after TBNA. Here we report this rare complication. Case. A 68-year-old woman presented with persis-tent cough. Chest computed tomography (CT) revealed mediastinal and right hilar lymphadenopathy. In July 2001, she underwent bronchoscopy for TBNA. TBNA was performed using a 19-gauge histology needle MW-319 (Mill-Rose Labora-tories, Mentor, OH, USA), and two aspirates were obtained from the carina. She did not complain of any chest pain throughout the procedure. On the next day, subcutaneous emphysema at the neck was observed. Chest X-ray and CT revealed pneumomediastinum. Both subcutaneous emphysema and pneumomediastinum spontaneously resolved by 5 days after TBNA. The etiology of the lymphadenopathy is still undetermined because pathologic examination of the TBNA specimens did not result in a definitive diagnosis. Therefore, she is now under observation. Conclusion. TBNA can, although rarely, cause complications including pneumomediastinum. Therefore, careful observation of the patient' s condition using chest X-ray is necessary.

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