Cryobiopsy and dye marking guided by electromagnetic navigation bronchoscopy before resection of pulmonary nodule.

BACKGROUND: Our aims were to explore the feasibility, safety, and efficacy of peroperative transbronchial lung cryobiopsy (TBLC) guided by electromagnetic navigation bronchoscopy (ENB) and ENB-guided methylene blue marking of presumably non-palpable pulmonary nodules, and to assess its impact on video-assisted thoracoscopic surgery (VATS) and postoperative lung function. METHODS: This approach was applied to 16 consecutive patients (Group A, mean age 64 years) who were compared retrospectively to a historical group of 49 patients (Group B, mean age 62 years) with similar nodules resected without guidance. The usefulness of dye marking was graded. The success rates of both ENB-guided TBLC and nodule localization through dye marking were computed. The type of resection, volume of resected parenchyma, duration of procedures, and postoperative lung function were compared between groups. Unpaired t-test, chi-square test, unpaired Wilcoxon test, and exact Fisher test were used when appropriate. RESULTS: Malignancy was pathologically proven in all patients. TBLC revealed malignancy in 9 patients in Group A. The success rate of ENB-guided dye marking was 94%. Lobectomy was less frequently performed in Group A than in Group B (p = 0.022). Forced expiratory volume in 1 s and total lung capacity were significantly less reduced in Group A than in Group B (p = 0.006 and p = 0.019, respectively). Combined procedure was longer than surgery alone (p<0.001), but its surgical part was shorter than VATS without guidance (p < 0.001). CONCLUSION: Peroperative ENB-guided TBLC with methylene blue marking of non-palpable lung nodules is feasible. A sparing lung parenchyma procedure could be achieved thanks to the ENB-guided dye marking before VATS.

Intratracheal Bleomycin Aerosolization: The Best Route of Administration for a Scalable and Homogeneous Pulmonary Fibrosis Rat Model?

Idiopathic pulmonary fibrosis (IPF) is a chronic disease with a poor prognosis and is characterized by the accumulation of fibrotic tissue in lungs resulting from a dysfunction in the healing process. In humans, the pathological process is patchy and temporally heterogeneous and the exact mechanisms remain poorly understood. Different animal models were thus developed. Among these, intratracheal administration of bleomycin (BML) is one of the most frequently used methods to induce lung fibrosis in rodents. In the present study, we first characterized histologically the time-course of lung alteration in rats submitted to BLM instillation. Heterogeneous damages were observed among lungs, consisting in an inflammatory phase at early time-points. It was followed by a transition to a fibrotic state characterized by an increased myofibroblast number and collagen accumulation. We then compared instillation and aerosolization routes of BLM administration. The fibrotic process was studied in each pulmonary lobe using a modified Ashcroft scale. The two quantification methods were confronted and the interobserver variability evaluated. Both methods induced fibrosis development as demonstrated by a similar progression of the highest modified Ashcroft score. However, we highlighted that aerosolization allows a more homogeneous distribution of lesions among lungs, with a persistence of higher grade damages upon time.