Optical Biopsy for Thoracic Lymph Nodes.
Optical Biopsy for Thoracic Lymph Nodes.
EUS-FNA is the recommended diagnostic examination of choice when patients present with
 suspected lower mediastinal lymph nodes on imaging. EUS-FNA is minimal invasive and low in
 costs, and although it has a good record in detecting diseases (eg confirm a nodal metastasis
 or granulomas) it has limitations in excluding diseases (missing metastases/ or granulomas)
 resulting in a false negative rate of 15-20%. Substantial limitations that most likely can be
 attributed to areas within the node that are not sampled during EUS-FNA tissue acquisition.
 Improved needle based EBUS/ EUS guided nodal diagnostics might result in improved quality of
 the fine needle aspirations, reduce in surgical diagnostic procedures , reduced costs and
 result in a shorter timebefore-treatment interval.
Needle based confocal laser endomicroscopy (nCLE) is a modern imaging technique, compatible
 with the conventional diagnostic aspiration needle, that uses an excitation laser light to
 create 'real-time' microscopic images of tissues. Therefore this technique provides
 additional information regarding the nodal status and could therefore improve the diagnostic
 yield of EUS-FNA. Specifically, we will describe the nCLE image characteristics of lymph
 nodes involved in lung cancer and sarcoidosis as well as in healthy lymph nodes. Improved
 characterization of mediastinal nodes might lead to improved diagnosis.
Inclusion Criteria:

 -  ≥18 years of age

 -  Suspected or tissue proven sarcoidosis (stage I or II based on CT/PET-CT) and referred
 for diagnostic endosonographic work up or

 -  Suspected or tissue proven NSCLC with suspected mediastinal lymph nodes within reach
 of EUS-FNA

 Exclusion Criteria:

 -  Inability and willingness to provide informed consent

 -  Inability to comply with the study protocol

 -  Patients with known allergy for fluorescein

 -  use of betablokker within 24 hours before procedure

 -  possible pregnancy or lactating women