Reproducibility of optical coherence tomography airway imaging

Optical coherence tomography (OCT) is a promising imaging technique to evaluate small airway remodeling. However, the short-term insertion-reinsertion reproducibility of OCT for evaluating the same bronchial pathway has yet to be established. We evaluated 74 OCT data sets from 38 current or former smokers twice within a single imaging session. Although the overall insertion-reinsertion airway wall thickness (WT) measurement coefficient of variation (CV) was moderate at 12%, much of the variability between repeat imaging was attributed to the observer; CV for repeated measurements of the same airway (intra-observer CV) was 9%. Therefore, reproducibility may be improved by introduction of automated analysis approaches suggesting that OCT has potential to be an in-vivo method for evaluating airway remodeling in future longitudinal and intervention studies. (C) 2015 Optical Society of Americ

Management of Multiple Primary Lung Cancer in Patients with Centrally Located Early Cancer Lesions

BackgroundPatients with centrally located early lung cancer (CLELC) are often heavy smokers with a considerably high risk of multiple primary lung cancer (MPLC) lesions; treatment strategies for such patients must preserve the cardiopulmonary function.MethodsBetween July 2004 and July 2008, patients with CLELC underwent photodynamic therapy (PDT) using NPe6, second-generation photosensitizer at Tokyo Medical University Hospital. Among these patients, we retrospectively analyzed MPLC, which was treated by surgery plus PDT or PDT alone and examined the effectiveness of PDT, and we propose a treatment strategy for patients with MPLC.ResultsA total of 64 patients with CLECL received NPe6-PDT, and MPLCs were found in 22 patients (34.4%) using sputum cytology and a bronchoscopical examination using autofluorescence bronchoscopy. Among these 22 patients, 10 patients underwent surgery for primary lung cancer and underwent NPe6-PDT for the treatment of secondary primary CLELC, one patient underwent PDT for CLELC as a primary lesion followed by an operation for peripheral-type lung cancer as a secondary primary lesion, and 11 patients underwent PDT alone for MPLC lesions (28 lesions) that were roentgenographically occult lung cancers. Among these 22 patients with MPLC including peripheral-type lung cancers, which were resected by surgery, all 39 CLELC lesions exhibited a complete response after PDT, and all patients were alive.ConclusionsFor patients with lung cancer with a long-term history of smoking, careful follow-up examinations after surgical resection are needed considering the incidence of metachronous primary lung cancers. PDT can play an important role for the treatment strategy for MPLC

Clinical trial of photodynamic therapy for peripheral-type lung cancers using a new laser device in a pilot study

Introduction/AimPhotodynamic therapy (PDT) involves the use of a tumor-specific photosensitizer and laser irradiation, and is one of the treatment options recommended for early centrally located lung cancers, but not yet for peripheral-type lung cancers. We developed a new laser probe, the composite-type optical fiberscope (COF), which allows accurate laser irradiation of a cancer lesion with simultaneous visualization of the lesion. In this study, we attempted a new endobronchial PDT technique using the new laser probe, and evaluated the effectiveness and feasibility of this novel PDT technique for peripheral lung cancers.MethodsThis phase I study was conducted in 7 patients with peripheral lung cancers (primary tumor ≤20 mm in diameter). We performed endobronchial PDT for these patients using the new laser probe and talaporfin sodium as the photosensitizer.ResultsWe performed PDT for 3 patients with peripheral lung cancer using a laser dose of 50 J/cm2 at 120 mW, and confirmed the feasibility of using this dose. Then, we escalated the laser dose to 100 J/cm2 in 4 additional patients. A total of 7 patients met our inclusion criteria. Evaluation at 2 weeks and 3 months after the PDT revealed no complication such as pneumonia or pneumothorax. At the evaluation conducted 6 months later, we found CR in 3 cases and SD in the remaining 4 cases.ConclusionPDT was found to be a feasible and non-invasive treatment modality for early peripheral-type lung cancer. In the future, PDT could become a standard treatment option for peripheral-type lung cancer

Reproducibility of optical coherence tomography airway imaging

Optical coherence tomography (OCT) is a promising imaging technique to evaluate small airway remodeling. However, the short-term insertion-reinsertion reproducibility of OCT for evaluating the same bronchial pathway has yet to be established. We evaluated 74 OCT data sets from 38 current or former smokers twice within a single imaging session. Although the overall insertion-reinsertion airway wall thickness (WT) measurement coefficient of variation (CV) was moderate at 12%, much of the variability between repeat imaging was attributed to the observer; CV for repeated measurements of the same airway (intra-observer CV) was 9%. Therefore, reproducibility may be improved by introduction of automated analysis approaches suggesting that OCT has potential to be an in-vivo method for evaluating airway remodeling in future longitudinal and intervention studies. (C) 2015 Optical Society of Americ

Validation of Airway Wall Measurements by Optical Coherence Tomography in Porcine Airways

<div><p>Examining and quantifying changes in airway morphology is critical for studying longitudinal pathogenesis and interventions in diseases such as chronic obstructive pulmonary disease and asthma. Here we present fiber-optic optical coherence tomography (OCT) as a nondestructive technique to precisely and accurately measure the 2-dimensional cross-sectional areas of airway wall substructure divided into the mucosa (WA_muc), submucosa (WA_sub), cartilage (WA_cart), and the airway total wall area (WAt). Porcine lung airway specimens were dissected from freshly resected lung lobes (N = 10). Three-dimensional OCT imaging using a fiber-optic rotary-pullback probe was performed immediately on airways greater than 0.9 mm in diameter on the fresh airway specimens and subsequently on the same specimens post-formalin-fixation. The fixed specimens were serially sectioned and stained with H&E. OCT images carefully matched to selected sections stained with Movat’s pentachrome demonstrated that OCT effectively identifies airway epithelium, lamina propria, and cartilage. Selected H&E sections were digitally scanned and airway total wall areas were measured. Traced measurements of WA_muc, WA_sub, WA_cart, and WA_t from OCT images of fresh specimens by two independent observers found there were no significant differences (p>0.05) between the observer’s measurements. The same wall area measurements from OCT images of formalin-fixed specimens found no significant differences for WA_sub, WA_cart and WA_t, and a small but significant difference for WA_muc. Bland-Altman analysis indicated there were negligible biases between the observers for OCT wall area measurements in both fresh and formalin-fixed specimens. Bland-Altman analysis also indicated there was negligible bias between histology and OCT wall area measurements for both fresh and formalin-fixed specimens. We believe this study sets the groundwork for quantitatively monitoring pathogenesis and interventions in the airways using OCT.</p></div

Correlating OCT imaging and histology.

<p>A) Experimental procedure for airway preparation and OCT imaging. B) Diagram outlining matching of H&E and OCT images, manual tracing of the morphological perimeters, and calculation of the airway wall area components. P_p = probe perimeter, P_i = luminal perimeter, P_mi = muscle inner perimeter, P_ci = cartilage inner perimeter, P_o = airway outer boundary perimeter. WA_muc = mucosal wall area, WA_sub = submucosal wall area, WA_cart = cartilage wall area. Scale bar = 1 mm.</p