[Confocal microscopic evaluation of epithelia of the larynx].

BACKGROUND

To evaluate mucosal changes of the true vocal cord, e. g. leukoplakia, microlaryngoscopy is needed to obtain tissue for histopathologic investigation. But there is a discrepancy between the amount of representative tissue necessary for pathology and the postoperative voice function. Thus, a diagnostic procedure that enables the surgeon to differentiate inflammation from dysplasia and carcinoma in situ intra-operatively is urgently needed. We are now reporting on our results using laser scanning microscopy to visualize larynx epithelia.

METHODS

The laser scanning microscope used in this ex vivo study is a combination of the Heidelberg Retina Tomograph HRTII and the Rostock Cornea Module. A 63 x water immersion objective lens was used for imaging.

PATIENTS

Seven larynx preparations of patients (age 54 to 62 years) with a T4 larynx carcinoma who underwent laryngectomy between 2003 and 2006 were examined.

RESULTS

Areas of epithelia of the true vocal cord of macroscopically normal appearance supplied images of healthy, but also inflamed laryngeal epithelia. The corresponding histopathologic sections prepared horizontally confirmed the regularity and homogeneity of the mucosa. The different layers of the lamina propria can be separated. In contrast to healthy and inflamed laryngeal mucosa, dysplasia, precancerous lesions and carcinoma-atypical cells were visible. In the latter entity a loss of cellular junctions characterized by lack of visualization of the cell membrane was apparent.

CONCLUSIONS

LSM supplies information of healthy, inflamed, but also pre-malignant and malignant mucosa changes of the larynx. The pilot study shows that both hyperkeratosis and extensive hyperplasia confine the visualization of the basement cell layer. Research projects have been initiated with the objective to develop a rigid endoscope with integrated LSM technology.