Indirect autofluorescence laryngoscopy in the diagnosis of laryngeal cancer and its precursor lesions

Abstract

Direct autofluorescence endoscopy of the larynx has proven to facilitate the detection and delineation of precancerous lesions, carcinoma in situ and cancer. The aim of the present study was to evaluate the diagnostic potential and limitations of this imaging technique applied during indirect laryngoscopy. In a prospective study, 116 patients with suspected precancerous or cancerous lesions were investigated preoperatively by indirect autofluorescence laryngoscopy. Autofluorescence was induced by filtered blue light (375-440 nm) of a xenon short-arc lamp and processed by a CCD camera system (D-light-AF System, Storz, Tuttlingen, Germany). Autofluorescence images were immediately assessed for diagnosis, compared to the direct autofluorescence picture obtained during microlaryngoscopy and compared to pathohistological findings. Comparable to direct autofluorescence images, normal laryngeal mucosa showed a typical green fluorescence signal. Moderate and high epithelial dysplasia, carcinoma in situ and cancer displayed a diminished green fluorescence. False negative results were related to extreme hyperkeratosis. False positive cases showed mild dysplasia with inflammatory reactions or scarring. In 103 cases (89%), we found concordant results. According to our results, the presented technique seems to be a promising diagnostic tool for the early detection of laryngeal cancer and its precursor lesions during indirect laryngoscopy. Scarring, marked hyperkeratosis and inflammation can limit the predictive value of the method.

Time-resolved autofluorescence spectroscopy for classifying normal and premalignant oral tissues

“…However, the applicability of this method is more or less restricted because of the requirement of removing human tissues and the difficulty of real-time diagnosis. During recent 20 years, a new diagnostic modality termed ''optical biopsy'' has been developed to distinguish different tissues (or cells) by optical methods [4][5][6]. These technologies are useful for clinical diagnosis, especially when the non-invasiveness and immediate results are requested.…”

Fluorescence investigations to classify malignant laryngeal lesions in vivo

“…14,17,20 Early studies of fluorescence in laryngeal lesions showed that the technique could be useful in a clinical setting, 25,27,29,32 and recent studies as well as the present study support this. 10,11,37 Technical Aspects. The present study presents an analysis of fluorescence spectra recorded from laryngeal lesions, indicating that it is possible to obtain diagnostic information of clinical impact using a few detection wavelength bands only, a technique that can be fully implemented in an imaging instrumentation.…”

Visual Servoing-based Registration of Multimodal Images

“…These images taken from (Arens et al, 2004) were acquired in two different points of view with known pose as shown in Fig. 7.…”