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(OMIM 154780) has a similar phenotype, but may be distinguished by a
more severe degree of hearing loss and its unique pattern of craniofacial
dysmorphism persisting into adulthood (Annunen et al. 1999; Ayme and
Preus 1984; Marshall 1958) (Fig. 6.5). The sensorineural hearing loss in these
disorders begins during early childhood and progresses over the ensuing
decades. The hearing loss is occasionally mixed (Lucarini et al. 1987) and
may be due to otitis media or its sequelae, especially in affected children.
Given the characteristic skeletal abnormalities, it is reasonable to postu-
late that the sensorineural hearing loss might be associated with gross mor-
phogenetic abnormalities of the inner ear. However, there are no reports
of temporal bone histopathology for these disorders, although computed
tomography (CT) scans of temporal bones of 19 Stickler's syndrome
patients and three Marshall syndrome patients have revealed no abnor-
malities (Griffith et al. 2000b; Szymko et al. 2000). Therefore, the bony
anatomy of the inner ear is at least grossly normal in these disorders.
FIGURE 6.5. Frontal and side views of an individual affected with Marshall syndrome
(Griffith et al. 1998). These facial features persisting into adulthood are character-
istic of Marshall syndrome and include severe midfacial growth deficiency, a small
upturned nose, and a prominent forehead. (Reprinted from Griffith et al., The Amer-
ican Journal of Human Genetics, Copyright 1998, with permission of The University
of Chicago Press.)
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