High-Resolution Volumetric Imaging of Lung Pathology: Improving Biopsy Sampling and Evaluation.
Lida P Hariri, Mari Mino-Kenudsen, Eugene J Mark, Matthew B Applegate, Guillermo J Tearney, Brett E Bouma, Melissa J Suter. Massachusetts General Hospital, Boston
Background: Histologic diagnosis of lung biopsies can be limited by small size or incomplete sampling. Larger tissue volumes can improve diagnostic yield, but may be difficult to obtain. Optical frequency domain imaging (OFDI) is a high resolution imaging modality providing 3-dimensional views of tissue microstructure to depths approaching 2mm. Large area volumetric OFDI is a possible adjunct to traditional biopsy to provide tissue images larger than biopsies and direct biopsy sampling. We performed OFDI through two approaches (bronchoscopic airway centered imaging and pleural based parenchymal imaging) and correlated to histopathologic findings.
Design: Airway and/or parenchymal images were obtained with a specialized bronchoscopic 2.4 French catheter and a bench-top external imaging system for 13 surgical and autopsy specimens. Corresponding tissue samples were processed for histologic comparison.
Results: OFDI was performed in 7 lung carcinomas (2 squamous cell, 1 adenosquamous, 1 adenocarcinoma, 1 undifferentiated carcinoma, and 2 mucinous bronchioloalveolar carcinomas [BAC]), 2 tracheal mucoepidermoid carcinomas, 1 carcinoid tumor, 1 cartilaginous hamartoma, and 2 interstitial fibrosis cases. Adjacent normal tissue was assessed when present. OFDI of normal airway allowed high resolution visualization of epithelium, lamina propria, submucosal glands, cartilage, blood vessels and alveolar attachments. Carcinomas exhibited architectural disarray, loss of normal airway and alveolar structures, and rapid light attenuation. Squamous cell carcinomas showed nested architecture on OFDI, while malignant glandular formations could be appreciated in adenocarcinomas and mucoepidermoid carcinomas. Mucinous BACs showed alveolar wall thickening with intra-alveolar mucin.
Conclusions: This study is the first demonstration of volumetric high-resolution microscopy with correlation to tissue-based diagnostics for evaluating lung tumors. While tissue biopsy remains essential as the gold standard, OFDI may provide a tool for in vivo identification of malignant features and improved tissue sampling with targeted guidance.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 284, Tuesday Afternoon