Fixation and detachment of superior and anterior malleolar ligaments in human middle ear: Experiment and modeling

The aim of this study is to investigate the function of the superior malleolar ligament (SML) and the anterior malleolar ligament (AML) in human middle ear for sound transmission through simulations of fixation and detachment of these ligaments in human temporal bones and a finite element (FE) ear model. Two laser vibrometers were used to measure the vibrations of the tympanic membrane (TM) and stapes footplate. A 3-D FE ear model was used to predict the transfer function of the middle ear with ligament fixation and detachment. The results demonstrate that fixations and detachments of the SML and AML had different effects on TM and stapes footplate movements. Fixation of the SML resulted in a reduction of displacement of the TM (umbo) and the footplate at low frequencies (f<1000 Hz), but also caused a shift of displacement peak to higher frequencies. Fixation of both SML and AML caused a reduction of 15 dB at umbo or stapes at low frequencies. Detachment of the SML had almost no effect on TM and footplate mobility, but AML detachment had a minor effect on TM and footplate movement. The FE model was able to predict the effects of SML and AML fixation and detachment.

[1]  Ugo Fisch,et al.  Fixation of the Anterior Mallear Ligament: Diagnosis and Consequences for Hearing Results in Stapes Surgery , 2003, The Annals of otology, rhinology, and laryngology.

[2]  Saumil N Merchant,et al.  Experimental and Clinical Studies of Malleus Fixation , 2005, The Laryngoscope.

[3]  Harold F. Schuknecht,et al.  Pathology of the Ear , 1974 .

[4]  S. Khanna,et al.  Tympanic-membrane vibrations in human cadaver ears studied by time-averaged holography. , 1972, The Journal of the Acoustical Society of America.

[5]  U. Fisch,et al.  The Anterior and Superior Malleal Ligaments in Otosclerosis: A Histopathologic Observation , 2002, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[6]  J. Nadol,et al.  Malleus Fixation: Clinical and Histopathologic Findings , 2002, The Annals of otology, rhinology, and laryngology.

[7]  John J. Rosowski,et al.  Experimental ossicular fixations and the middle ear’s response to sound: Evidence for a flexible ossicular chain , 2005, Hearing Research.

[8]  C. Moon,et al.  Primary malleus fixation: Diagnosis and treatment , 1981, The Laryngoscope.

[9]  S. Daniel,et al.  An Experimental Study of Tympanic Membrane and Manubrium Vibrations in Rats , 2006, Audiology and Neurotology.

[10]  Y. Young,et al.  Vestibular Evoked Myogenic Potentials in Newborns , 2006, Audiology and Neurotology.

[11]  Rong Z Gan,et al.  Human Middle Ear Transfer Function Measured by Double Laser Interferometry System , 2004, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[12]  V. Goodhill.  Bilateral malleal fixation and conductive presbycusis. , 1969, Archives of otolaryngology.