Hageman M J
J Laryngol Otol. 1977 Jul;91(7):575-84. doi: 10.1017/s0022215100084073.
The dominant hereditary form of deafness as part of Waardenburg's syndrome was found in 12 (35%) of 34 patients never previously described with Waardenburg's syndrome among 5 families in the Netherlands. Extensive audiometric examination could be performed in 11 patients, 5 patients with deafness on both sides and 6 patients with hearing deficiency on one side. The hearing loss could be divided into 4 types: (type I) (sub) total deafness on both sides; (type II) serious lack of hearing on both sides; (type III) (sub) total deafness on one side; (type IV) moderate hearing deficiency on one side, particularly in the low frequencies. An extensive review was made of the more than 1,000 patients with Waardenburg's syndrome described in the literature. This revealed that deafness in both ears (the most serious expression of the syndrome) occurred in about 25% of the patients with Waardenburg's syndrome type I (including dystopia canthorum) and in 50% of the patients with Waardenburg's syndrome type II (without dystopia canthorum). This striking difference is connected with the close relationship between deafness and pigmentary disorders.