Comparative Impacts of Scala Vestibuli Versus Scala Tympani Cochlear Implantation on Auditory Performances and Programming Parameters in Partially Ossified Cochleae

A major component of minimally invasive cochlear implantation is atraumatic scala tympani (ST) placement of the electrode array. This work reports on a semiautomatic planning paradigm that uses anatomical landmarks and cochlear surface models for cochleostomy target and insertion trajectory computation. The method was validated in a human whole head cadaver model (n=10ears). Cochleostomy targets were generated from an automated script and used for consecutive planning of a direct cochlear access (DCA) drill trajectory from the mastoid surface to the inner ear. An image-guided robotic system was used to perform both, DCA and cochleostomy drilling. Nine of 10 implanted specimens showed complete ST placement. One case of scala vestibuli insertion occurred due to a registration/drilling error of 0.79 mm. The presented approach indicates that a safe cochleostomy target and insertion trajectory can be planned using conventional clinical imaging modalities, which lack sufficient resolution to identify the basilar membrane.

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Les migrations du porte-électrodes de la scala tympani à la scala vestibuli ont-elles un impact sur les performances après implantation cochléaire ?

Annales françaises d Oto-rhino-laryngologie et de Pathologie Cervico-faciale ◽

10.1016/j.aforl.2013.06.239 ◽

2013 ◽

Vol 130 (4) ◽

pp. A71-A72

Author(s):

M. Marx ◽

B. Fraysse ◽

N. Martin-Dupont ◽

B. Escude ◽

M. Laborde ◽

...

Keyword(s):

Scala Tympani ◽

Scala Vestibuli

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Clinical outcomes of scala vestibuli cochlear implantation in children with partial labyrinthine ossification

Acta Oto-Laryngologica ◽

10.1080/00016480802032819 ◽

2009 ◽

Vol 129 (3) ◽

pp. 273-280 ◽

Cited By ~ 7

Author(s):

Yung-Song Lin

Keyword(s):

Clinical Outcomes ◽

Cochlear Implantation ◽

Scala Vestibuli

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Na and nonelectrolyte entry into inner ear fluids of the rat

AJP Renal Physiology ◽

10.1152/ajprenal.1987.253.1.f50 ◽

1987 ◽

Vol 253 (1) ◽

pp. F50-F58 ◽

Cited By ~ 4

Author(s):

O. Sterkers ◽

E. Ferrary ◽

G. Saumon ◽

C. Amiel

Keyword(s):

Cerebrospinal Fluid ◽

Inner Ear ◽

Lateral Ventricle ◽

Endothelial Barrier ◽

Scala Tympani ◽

Epithelial Secretion ◽

Kinetics Of ◽

Hydrophilic Solutes ◽

Inner Ear Fluids ◽

Scala Vestibuli

Kinetics of hydrophilic solute entry into endolymph (EL), perilymph (PL), and cerebrospinal fluid (CSF) were studied after intravenous administration (sodium, urea, glycerol, mannitol, sucrose) and cerebral lateral ventricle injection (urea, sucrose) of tracers in anesthetized rats. Samples of cochlear EL, PL of scala vestibuli (PLV), PL of scala tympani (PLT), and cisternal CSF were obtained. The data showed slow entry of tracers in PLV, PLT, and CSF as follows: Na greater than urea greater than mannitol approximately sucrose; slower entry of mannitol and sucrose in PLT and CSF than in PLV; 1 h delayed peak of radioactivity in PLV compared with the immediate peaks in PLT and CSF after CSF injection, and the value of PLV peak was 13% that in CSF; extremely slow entry of nonelectrolytes in EL. These results indicate that PLV originates mainly from plasma across a blood-perilymph barrier that restricts the entry of small hydrophilic solutes. The blood-perilymph barrier is most likely composed of an endothelial barrier associated with an epithelial secretion. The latter could be located at the vasculo-epithelial zone of the spiral limbus.

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K, Cl, and H2O entry in endolymph, perilymph, and cerebrospinal fluid of the rat

AJP Renal Physiology ◽

10.1152/ajprenal.1982.243.2.f173 ◽

1982 ◽

Vol 243 (2) ◽

pp. F173-F180 ◽

Cited By ~ 6

Author(s):

O. Sterkers ◽

G. Saumon ◽

P. Tran Ba Huy ◽

C. Amiel

Keyword(s):

Cerebrospinal Fluid ◽

Potassium Chloride ◽

Intravenous Administration ◽

Compartmental Analysis ◽

Water Entry ◽

Scala Tympani ◽

Rapid Turnover ◽

Kinetics Of ◽

Scala Vestibuli

The kinetics of radioactive potassium, chloride, and water entry into endolymph, perilymph, and cerebrospinal fluid were studied after intravenous administration of tracers in anesthetized and nephrectomized rats. Samples of cochlear endolymph, perilymph of scala vestibuli, perilymph of scala tympani, and cisternal cerebrospinal fluid were obtained. The data showed: 1) a rapid turnover of water in endolymph, perilymph, and cerebrospinal fluid, since 3H2O equilibrated with plasma in a few minutes; 2) a slow entry of 42K and 36Cl in perilymph, since 36Cl equilibrated with plasma after 2 h and 42K did not at 6 h; 3) an extremely slow entry of 42K and 36Cl in endolymph, since no equilibrium with plasma was obtained within the 5 h of the experiments. The comparison of the compartmental analysis of our data with the results of other studies using perilymphatic perfusion of tracers indicated that perilymph rather than plasma may be considered as the precursor of endolymph.

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Facilitated transfer of glucose from blood into perilymph in the rat cochlea

AJP Renal Physiology ◽

10.1152/ajprenal.1987.253.1.f59 ◽

1987 ◽

Vol 253 (1) ◽

pp. F59-F65 ◽

Cited By ~ 2

Author(s):

E. Ferrary ◽

O. Sterkers ◽

G. Saumon ◽

P. Tran Ba Huy ◽

C. Amiel

Keyword(s):

Cerebrospinal Fluid ◽

Linear Function ◽

Intravenous Administration ◽

Glucose Concentration ◽

Concentration Ratio ◽

Facilitated Transport ◽

Scala Tympani ◽

Glucose Transfer ◽

Rat Cochlea ◽

Scala Vestibuli

The transport of glucose into cochlear endolymph, perilymph of scala vestibuli and perilymph of scala tympani, and cerebrospinal fluid (CSF) was studied after intravenous administration of tracers of D-glucose, L-glucose, and 3-O-methyl-D-glucose in anesthetized rats. The data showed that D-glucose concentrations in perilymph of scala vestibuli, perilymph of scala tympani, and CSF were approximately 50%, and in endolymph less than 10%, that in plasma; D-glucose concentration in perilymph of scala vestibuli, perilymph of scala tympani, and CSF increased as a linear function of that in plasma; D-glucose entry into perilymph of scala vestibuli, perilymph of scala tympani, and CSF was more rapid than that of L-glucose; after infusion of 3-O-methyl-D-glucose, but not after that of mannitol, both the D-glucose concentration ratio of perilymph over plasma and D-glucose transfer into perilymph were lowered. These results indicate that D-glucose enters into perilymph of scala vestibuli by a facilitated transport, possibly located at the blood-perilymph barrier.

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