Ultrasonography (US) is a well-known and valuable method of detecting lymph nodes in the neck. It is widely used in the preoperative neck assessment and in follow-up patients treated for head and neck cancer. The aim of the study was to compare the larynx cancer patients in two decades: the 80-ies and the 90-ies and the influence of a single diagnostic tool, i.e. ultrasonography, on therapeutic decisions and final results. Two groups of patients were selected: 737 patients treated between 1981-1985 (before the introduction of US) and 840 patients treated between 1991-1995 (routinely examined with the help of US) in ENT Dept. of Karol Marcinkowski University of Medical Sciences in Poznań. We aimed at analysing the percentages of neck metastases at the moment of diagnosis, the frequency of particular types of primary neck treatment, the percentages of neck recurrences, their advancement at the diagnosis and the methods of secondary treatment. Particular attention to feasibility of salvage was paid. Mean survival time in the group of patients with recurrence and the overall 5-year-long survival rates were analysed. No marked differences were stated between both groups as to epidemiological data, primary tumor advancement and types of the performed larynx surgery. Neck metastases occurred in both groups, 34% and 42%, respectively. Relapse rates were 12.9% and 12.6%, respectively. It was found that the number of elective neck dissections over the period given above became smaller, the number of radical neck dissections was stable, while the number of patients referred to wait and see policy increased. The number of successful neck salvage surgeries markedly increased while the number of patients not qualified for salvage decreased. For the both studied data, the curves on diagrams cross around the year 1992. The turning point situated in this time shows that ultrasound, introduced in 1991, gradually changed the types of primary treatment and possibilities of salvage neck treatment. The statistically significant differences in both groups were shown as to: types of the initial i.e. first neck treatment, relapse rate and the possibility of performing surgical salvage, while the only change was the introduction of a new diagnostic tool, i.e. neck ultrasonography. Survival rate was markedly better in the second group of patients. The methods of qualifying patients for the primary neck treatment and follow-up schedule have been changed since ultrasonography diagnostics was introduced in 1991 for routine assessment of the neck lymphatics in the larynx cancer patients. Strict follow-up schedule allow for early detection and successful treatment in high percentage of relapses.