Probe-based Confocal Laser Endomicroscopy (pCLE) in the Diagnosis of Diffuse Parenchymal Lung Diseases: Two Cases

Case Report

Austin J Pulm Respir Med 2014;1(4): 1018.

Probe-based Confocal Laser Endomicroscopy (pCLE) in the Diagnosis of Diffuse Parenchymal Lung Diseases: Two Cases

Levent Dalar1*, Cengiz Özdemir2, Sinem Nedime Sökücü2, Ahmet Levent Karasulu2, Sedat Altin2, Neslihan Fener3 and Filiz Kosar2

1Department of Pulmonary Medicine, Istanbul Bilim University, Turkey

2Department of Pulmonology, Yedikule Teaching Hospital for Pulmonology and Thoracic Surgery, Turkey

3Department of Pathology, Yedikule Teaching Hospital for Pulmonology and Thoracic Surgery, Turkey

*Corresponding author: Dalar L, Department of Pulmonary Medicine, School of Medicine, Istanbul Bilim University, Sisli Florence Nightingale Hospital, Abidei Hurriyet cad. No: 164, 34370 Sisli, Istanbul, Turkey

Received: June 26, 2014; Accepted: August 25, 2014; Published: August 28, 2014


Probe-based confocal laser endomicroscopy (pCLE) has been used in bronchology since 2005. It is a promising method, especially in the diagnosis of parenchymal lung diseases, peripheral nodules, and post-lung transplantation rejection. Optical biopsy samples from pCLE have been previously published and discussed in the diagnosis of some parenchymal diseases. The present article discussed the optical biopsy imaging of a case with Pneumocystis jirovecii pneumonia and a case with early pulmonary fibrosis, which were obtained via pCLE. These are the first two cases in which this method has been used.

Keywords: Interstitial; Optical biopsy; Pneumocystis pneumonia; Pulmonary fibrosis


The working principle of confocal endomicroscopy was first described in 1957 and it is based on the narrow-point illumination of the light source focused on a single point in the sample and the return of the reflected light through a small opening or a pinhole in the probe pathway [1-3]. This procedure allows for the exclusion of the information from outside, under, and above the focused area, and to obtain high quality images of a very thin focusing field. It is called “confocal” due to having both illumination and detection systems in the same focal plane. In this way, since there is no longer a need to obtain a biopsy from the targeted area or at least due to the biopsies that can be taken from the exactly targeted area and from the spot, a diagnosis can be achieved.

CellVizio (Mauna Kea Tech, Paris, France) confocal endomicroscopy system employs a proximal scanning system. Confocal microscopy allows in vivo imaging of cells and tissues by fragmentation through obtaining lateral and axial resolutions.

When stimulated by a laser light of 488 nm, various extracellular and cellular fluorophores containing intracellular flavines resulting from the epithelial cells and the cross links between the collagen and elastin in the subepithelial area are resolved at different concentrations.

The microspectrometer studies demonstrated that the main fluorescence signal is spread by the elastin component of human bronchial and alveolar system at this wavelength. It can be easily performed during a routine fiber optic bronchoscopy applied under local anesthesia [4,5]. The in vivo bronchial pCLE imaging technique is simple: a mini-probe is placed through the 2-mm operating channel of the bronchoscope and the probe tip is applied over the bronchial mucosa under visual inspection. With a 50 μm under contact surface for the depth of the focus, the system may likely provide imaging of the basal lamina densa and lamina reticularis, the first layers of the bronchial subepithelial connective tissue. Elastin is found in the acinus, axial backbone of the alveolar ducts, and alveolar entries, and also in the outer sheath of the extra alveolar microvessels. Alveolar fluorescent imaging in active smokers severely differs from the imaging performed in non-smokers. The alveolar areas of the smokers are generally full of high florescent cells corresponding to the alveolar florescent macrophages [4,6].

In the present article, the potentials of the system were discussed, accompanied by the optical biopsy images of a case with Pneumocystis jirovecii pneumonia (PCP) and a case with early pulmonary fibrosis, of which the imaging of distal airways was performed via probe-based, fibered confocal laser endomicroscopy (pCLE) by using CellVizio (Mauna Kea Technologies, Paris, France).


Case 1

A 32-year-old male patient who admitted to our polyclinic with shortness of breath, cough, sputum, and fever did not have any known medical history and he had shortness of breath, fever, cough, and sputum for two months. He was charged under the pre-diagnosis of pneumonia. The patient was taken into the intensive care unit (ICU) upon the worsening of respiratory failure. The patient was monitored in the ICU via the support of non-invasive mechanical ventilation (NIMV) and the HIV serology was found positive. Since the radiological and clinical appearances were consistent, P. jirovecii pneumonia was considered. Figures 1 & 2 present the chest X-rays and the computed tomography sections of thorax of the patient.