In @ patients with laryngeal or hypopharyngeal , nasal or nasopharyngeal , or oral or oropharyngeal cancer , we acoustically analyzed nasality , vowel space , precision , and strength of articulation in @ speech sounds ( / a / , / i / , / u / , / p / , / s / , / z / , / @ / , / t / , / tj / , / k / , / x / , / r / ) before treatment and @ weeks and @ year after treatment .