Development of novel layered polyglycolic acid sheet for regeneration of critical-size defect in rat trachea.

OBJECTIVES: Polyglycolic acid (PGA) sheets are difficult to adapt to the central airway because of poor durability against high air pressure. Therefore, we developed a novel layered PGA material to cover the central airway and examined its morphologic traits and functional performance as a potential tracheal replacement. METHODS: A critical-size defect in rat cervical tracheas was covered with the material. Morphologic changes were bronchoscopically and pathologically evaluated. Functional performance was evaluated by regenerated ciliary area, ciliary beat frequency and ciliary transport function determined by measuring the moving distance of microspheres dropped onto the trachea (µm/s). The evaluation time points were 2 weeks, 1 month, 2 months and 6 months after surgery (n = 5, respectively). RESULTS: Forty rats underwent implantation, and all survived. Histological examination confirmed ciliated epithelization on the luminal surface after 2 weeks. Neovascularization was observed after 1 month, tracheal glands after 2 months and chondrocyte regeneration after 6 months. Although the material was gradually replaced by self-organization, tracheomalacia was not bronchoscopically observed at any time point. The area of regenerated cilia significantly increased between 2 weeks and 1 month (12.0% vs 30.0%; P = 0.0216). The median ciliary beat frequency significantly improved between 2 weeks and 6 months (7.12 vs 10.04 Hz; P = 0.0122). The median ciliary transport function was significantly improved between 2 weeks and 2 months (5.16 vs 13.49 µm/s; P = 0.0216). CONCLUSIONS: The novel PGA material showed excellent biocompatibility and tracheal regeneration both morphologically and functionally 6 months after tracheal implantation.

Electromagnetic navigation bronchoscopy versus virtual bronchoscopy navigation for improving the diagnosis of peripheral lung lesions: analysis of the predictors of successful diagnosis.

PURPOSE: To investigate if electromagnetic navigation bronchoscopy (ENB) improves the diagnostic yield for peripheral lung lesions from that achieved by virtual bronchoscopy navigation (VBN). METHODS: This retrospective study compared the results of 100 ENB-transbronchial lung biopsies (TBLBs) with those of 50 VBN-TBLBs at a single institution. RESULTS: ENB improved the diagnostic yield significantly compared with VBN (64.0% for 19.4 ± 9.0 mm tumors vs. 46.0% for 27.6 ± 8.9 mm tumors; p < 0.0001). Irrespective of the bronchus sign, ENB was more favorable than VBN, with 81.0% (47/58) achieved by ENB vs. 60.0% (21/35) achieved by VBN in the presence of the positive bronchus sign (p = 0.0283), and 40.5% (17/42) achieved by ENB vs. 13.3% (2/15) achieved by VBN in the absence of the bronchus sign (p = 0.0431). Univariate analysis identified tumor size (p = 0.0048), amount of intravenous sedation (p = 0.0182), registration time (p = 0.0111), minimum distance to target (p = 0.0244), and the bronchus sign (p < 0.0001) as factors that affected the yield significantly for ENB. Multivariate analysis identified the bronchus sign (odds ratio 6.74; 95% CI 1.84-24.7) and the registration time (OR 1.01; 95% CI 1.00-1.02) as significant factors. CONCLUSIONS: Despite the bronchus sign being a significant factor, ENB improved the diagnostic yield of smaller lesions significantly, compared with VBN, regardless of the bronchus sign.

A case of pulmonary sclerosing pneumocytoma in the hilar lesion.

Pulmonary sclerosing pneumocytoma (PSP) arising from the hilar lesion is extremely rare. We report an asymptomatic 70-year-old female with a thoracic tumor of unknown origin. Contrast-enhanced chest tomography showed a poorly and heterogeneously enhanced 40-mm tumor compressing the left upper lobe, bronchus, and pulmonary arteries. Positron-emission tomography did not detect abnormal integration in the tumor. Surgical resection was planned to confirm diagnosis and avoid further compression on the structures. Intraoperative findings revealed a dark red-colored tumor, projecting from the left upper lobe in the hilar lesion. Left upper lobectomy was performed through video-assisted thoracoscopic surgery to achieve complete resection and avoid contact bleeding. Immunohistochemical examination revealed the presence of PSP.

A case of surgery for congenital esophagobronchial fistula accompanied by a destroyed lung.

Congenital esophagobronchial fistula (EBF) is rarely seen in adults. We report a case of EBF detected in adulthood with a destroyed lung. A 67-year-old man experienced repeated pneumonia during his childhood. Since the age of 38, he had often suffered from bloody phlegm and always had a cough and sputum during oral intake. Before cardiac surgery for atrial fibrillation and valvular disease, computed tomography (CT) detected bronchiectasis, which could cause pulmonary bleeding during heart surgery, and the patient was introduced to our hospital for lung resection. A fistula between the esophagus and the right lower lung lobe was found using CT, esophagoscopy, and esophagography. Contrast CT and angiography revealed an abnormal artery branching from the inferior phrenic artery into the lobe. As indicated by intraoperative findings, the middle and lower lobes had strongly adhered to chest wall and diaphragm, but we located the fistula easily without adhesion to the surroundings, severed it using an automatic stapler, and resected the middle and lower lobes. The symptoms disappeared immediately, and the patient was uneventfully discharged.The diagnosis of congenital EBF was established with intraoperative findings and pathological exam. The existence of pulmonary sequestration was suggested because of the long-term absence of any symptoms during his adulthood, the tract of the EBF running into the lung, not directly into the bronchus, and a septum pathologically detected in the right lower lobe. A congenital EBF should be considered for differential diagnosis in cases of limited bronchiectasis in elderly people.

Ectopic thymic carcinoma presenting as an intrathoracic mass.

An asymptomatic 83-year-old man was found to have a right intrathoracic tumor. Computed tomography demonstrated a soft-tissue density mass measuring 55 × 25 × 22 mm adjacent to the right anterior chest wall. At surgery, the tumor was found to adhere to the diaphragm and right lung, contiguous with the mediastinal fat tissue. Histology of the resected specimen demonstrated proliferation of spindle and sarcomatous cells with multinucleated giant cells. Thus the tumor was diagnosed as undifferentiated thymic carcinoma and was considered to have arisen from ectopic thymic tissue. At 2 years postoperatively, the patient had no evidence of recurrence.

Severe Mediastinitis and Pericarditis After Transbronchial Needle Aspiration.

Endobronchial ultrasonographically guided transbronchial needle aspiration (EBUS-TBNA) is now widely performed for mediastinal lymph node staging of lung cancer. Although this procedure is less invasive than mediastinoscopy, some infectious complications have been reported. We report the successful use of pericardial and mediastinal drainage in a case of acute severe mediastinitis with pericarditis after EBUS-TBNA.

Thrombus Removal by Acute-phase Endovascular Reperfusion Therapy to Treat Cerebral Embolism Caused by Thrombus in the Pulmonary Vein Stump after Left Upper Pulmonary Lobectomy: Case Report.

Thrombus formation in a pulmonary vein stump after pulmonary lobectomy is extremely rare, but can trigger cerebral embolism of unknown cause. We encountered a case of cerebral embolism in a 58-year-old man 2 days after left upper lobectomy. Since intravenous administration of recombinant tissue plasminogen activator was contraindicated, thrombus removal by endovascular reperfusion therapy was performed. Cerebral angiography showed left internal carotid artery occlusion. Thrombus removal using a retrieval device was performed and complete recanalization of the left internal carotid artery was obtained. Although blood abnormalities or arrhythmia such as atrial fibrillation were not observed, thrombus in the left upper pulmonary vein stump was detected with contrast-enhanced computed tomography of the body trunk, which was therefore considered as the source of cerebral embolism. The patient is continuing on anticoagulant therapy to prevent embolism recurrence caused by thrombus formation in the pulmonary vein resection stump. To the best of our knowledge, this is the first report of thrombus removal by acute-phase endovascular reperfusion therapy to treat cerebral embolism likely caused by thrombus formation in the pulmonary vein stump after left upper lobectomy. When cerebral embolism of unknown cause develops after left upper lobectomy, thrombus formation in the pulmonary vein stump should be considered among the differential diagnoses. For acute-phase onset of cerebral embolism after pulmonary lobectomy, thrombus removal by endovascular reperfusion therapy may be considered as one of the therapies.

Four cases of contralateral pneumothorax after pneumonectomy.

Contralateral pneumothorax after pneumonectomy (CPAP) is a rare but potentially fatal condition. Therefore, when treating CPAP prevention of recurrence is very important. Despite a number of case reports about CPAP, its management is still controversial. We describe 4 cases of CPAP that were treated successfully by bullectomy and coverage with absorbable polyglactin mesh.