Confocal Laser Endomicroscopy as a Guidance Tool for Transbronchial Lung Cryobiopsies in Interstitial Lung Disorder

Abstract

Background: Transbronchial cryobiopsy (TBCB) of the lung parenchyma is a minimally invasive alternative for surgical lung biopsy in interstitial lung disease (ILD) patients. Drawbacks are the nondiagnostic rate and complication risk of pneumothorax and bleeding. Fluoroscopy is the current guidance tool for TBCB, which is limited by 2D imaging and a radiation dose for the patient. Confocal laser endomicroscopy (CLE) is a high-resolution imaging technique that provides immediate feedback during bronchoscopy about the elastin fiber network of peripheral lung areas. Both the visceral pleura and fibrotic lung areas consist of elastin fibers and are therefore potentially detectable with CLE. Objectives: To investigate whether CLE is capable of (1) distinguishing fibrotic from normal alveolar areas and (2) identifying the pleura. Methods: In and ex vivo CLE imaging obtained during bronchoscopy was compared with histology of lung biopsies in 14 ILD patients. Results: CLE imaging of the alveolar compartment was feasible in all patients without adverse events. Based on CLE imaging, key characteristics that influence both diagnostic yield (dense fibrotic areas) and complication rate (pleura and subpleural space) were visualized. Conclusions: CLE seems a promising alternative to fluoroscopy as a guidance tool for TBCB procedures.

Avances en tomografía de coherencia óptica y endomicroscopía confocal láser en enfermedades pulmonares

“…e imagen por nECL mostrando las fibras de elastina (e) de la cápsula de un nódulo linfático. f imagen por nECL mostrando linfocitos (l) en un nódulo linfático reactivo (Wijmans et al [85]). pECL, endomicroscopía confocal láser con sonda; s, septos; a, espacio alveolar; nECL, endomicroscopía confocal láser con aguja.…”

“…b Imagen por pECL que muestra un incremento en la densidad de red intacta de fibra de elastina alveolar. c Imagen por pECL que muestra un incremento en la densidad de red engrosada de fibra de elastina alveolar, con pérdida de la arquitectura normal (Wijmans et al [85]). P, sonda.…”

Transbronchial Cryobiopsy in the Diagnosis of Fibrotic Interstitial Lung Disease

“…In the near future, integration of new endoscopic guidance tools for the cryoprobe may be helpful to target the best biopsy areas with greater precision, potentially further increasing the diagnostic yield and reducing the complication rate of the technique. [46][47][48] Several studies have evaluated the diagnostic utility of cryobiopsy in the setting of the multidisciplinary diagnosis of diffuse lung disease 17,24,27,29,37,40,41 and it has been found it to be either similar to 49,50 or greater than 17,33,36,51 the histologic diagnostic yield alone. In a meta-analysis of 731 patients the pooled estimate of diagnostic yield for histologic interpretation of cryobiopsy alone was greater than the pooled estimate of multidisciplinary diagnosis of cryobiopsy (83% [95% CI, 73-94] versus 79% [95% CI, 65-93], respectively) 38 .…”

Automated evaluation of probe-based confocal laser endomicroscopy in the lung

“…selected, segmented [34] before analysis with the presented method. This would further the methods real-time capability and offer attending physicians suggestions of interesting ROI rather than confirmation.…”