[Large endolymphatic duct and sac syndrome : part 2: clinical manifestations].

Objective: The aim of this study was to clarify the clinical course of large endolymphatic duct and sac syndrome (LEDS). Although LEDS is the most common form of radiologically detectable inner ear malformation associated with sensorineural hearing loss (SNHL), it is relatively unknown in the German-speaking countries. We hoped to derive useful pointers for clinical care.
Methods: We evaluated the clinical audiometric records and imaging findings of 169 patients with clinically suspected inner ear malformation seen between 1994 and 2003. Following identification of all LEDS cases, we serially investigated the anamnestic and functional data with regard to severity and course.
Results: Among 169 patients, 17 (median age 12 years; 12 females) showed LEDS. A total of 28 ears were affected. Clinically, most cases were of prelingual or perilingual onset and displayed steady or fluctuatingly progressive severe SNHL with emphasis on the high frequencies or deafness. Episodes of sudden hearing loss were relatively frequent. No correlation could be demonstrated between the severity of morphological changes and the degree of SNHL.
Conclusion: Progression of SNHL and episodes of sudden hearing loss were seen mainly in late childhood or adolescence. This should be taken into account when informing and advising patients and planning therapy.