VISERA S OTV-S500:
Expanding the Potential of Head and Neck Practice with NBI and Stroboscopy

Endoscopic examination plays a central role in head and neck practice, with white-light imaging serving as the fundamental modality. Using white-light observation, most elevated lesions, including vocal fold polyps, can be accurately diagnosed. Recent technological advances have markedly improved image quality, enabling more detailed observation and enhanced diagnostic performance. Furthermore, the ability to digitally record endoscopic findings has made endoscopy an indispensable diagnostic tool in contemporary head and neck practice.
However, the early detection of superficial laryngopharyngeal car cinoma, which has been increasing in recent years, remains challenging with white-light observation alone. In addition, evaluation of vocal fold vibration in voice disorders and assessment of tumor depth in glottic carcinoma are not possible using white-light imaging alone. These evaluations become feasible only through narrow band imaging (NBI) and stroboscopic observation, respectively. Such highprecision diagnostic modalities are clinically essential, as they directly contribute to appropriate treatment selection and improved therapeutic outcomes.
With conventional otolaryngologic endoscopes, NBI observation has often been limited by lower resolution compared with gastrointestinal endoscopes and by frequent halation due to surface reflection, which can complicate diagnosis. Similarly, stroboscopic observation has frequently suffered from insufficient illumination, making accurate assessment of mucosal vibration difficult, particularly in patients with strong reflectivity where close observation is challenging.
Moreover, when NBI for microvascular assessment and stroboscopy for depth evaluation are used in combination for the diagnosis of early glottic carcinoma, switching between different light sources is required, resulting in procedural complexity for both healthcare providers and patients.

VISERA S OTV-S500 is a light-source-integrated endoscopic system that enables the use of a stroboscopic observation mode through software upgrades via a portable memory port. This system eliminates the need to change light sources and allows seamless, one-touch switching between NBI and stroboscopic observation.
Functionally, the system employs narrow-spectrum violet LEDs in addition to white LEDs, thereby enhancing image contrast during NBI observation. Noise reduction is achieved through frame accumulation and image processing techniques. Furthermore, increased luminous intensity enabled by high-current output, combined with the integrated light-source design, allows advanced in-system image processing. This configuration suppresses flicker caused by mismatches between the camera shutter speed and the light source flashing cycle.
Another notable feature of the system is its compact and lightweight design. The main unit measures 308 mm in width, 157 mm in height, and 461 mm in depth, with a total weight of only 10.6 kg, facilitating easy transportation and installation in operating rooms and other clinical settings.

White-light observation revealed an erythematous lesion with an irregular surface extending from the left soft palate to the anterior palatine arch; however, accurate assessment of lesion extent was difficult. NBI observation demonstrated a well-demarcated brownish area with proliferative atypical microvessels. Compared with conventional systems (OTV-S190), VISERA S OTV-S500 provided enhanced contrast, allowing clearer delineation of tumor extension.

Following observation of the hypopharynx using the modified Killian m ethod, slight erythema was noted on the mucosa of the right pyriform sinus. NBI observation revealed a clearly demarcated brownish area with atypical microvascular proliferation at the same site. Compared with VISERA ELITE OTV-S190, VISERA S OTV-S500 provided stronger contrast and improved lesion visibility.

Under general anesthesia, the left pyriform sinus was observed after hypopharyngeal exposure. A well-defined brownish area with atypical microvessels was identified.
Compared with VISERA ELITE OTV-S190, VISERA S OTV-S500 demonstrated reduced color and luminance unevenness due to noise reduction processing, improved depth of field, and sharper edge definition, resulting in clearer visualization of the lesion.