Cochlear abnormalities in Alport's syndrome
L. G. Johnsson and I. K. Arenberg
The cochleae of four patients with a diagnosis or suspicion of Alport's
syndrome were examined by microdissection and surface preparations. Strial
atrophy, found in all cases, was most pronounced in the middle and apical
turns and mainly involved the inferior margin of the stria. Numerous
vacuoles were seen in the spiral ligament behind the atrophic stria. The
youngest patient, aged 16 years, who had little or no hearing loss, showed
limited hair cell degeneration. The other two patients had severe hearing
loss and extensive sensory cell loss of unusual distribution. In the
specimens from the second patient, the extent of hair cell loss was fairly
even throughout, but the loss of inner hair cells was far more severe than
the loss of outer hair cells. In the third case, the loss of outer hair
cells was most pronounced in the apical half of the cochlea. All of these
specimens had only a mild secondary nerve degeneration. The specimens from
the fourth patient were poorly preserved and showed only nerve
degeneration.
