Cochlear SPrint Sound Processor Informações Técnicas descarregar pdf (Página 75)

CLINICAL GUIDANCE | SECTION TWO

Prior to programming, check with the surgery report to conﬁrm which

electrode array is in which turn of the cochlea and whether the orientation is

standard or retrograde, as this will affect electrode-to-channel allocation.

2.1.2.1 Programming the Double Array

The Nucleus 24 Double Array can be programmed in the same modes as the

Nucleus 24 (CI24M) except for common ground. However, it is recommended

to use MP1+2 where possible as this will result in lower T- and C-levels. In

monopolar mode (MP1, MP2, MP1+2), channels 1 to 11 on the basal array

and 12 to 22 on the apical array can be used in the MAP. In bipolar mode, the

arrangement of the electrode arrays within the cochlea and the stimulation

mode (BP+1, BP+2, etc.) will determine which electrodes can be used in the

MAP. Measure T- and C- levels in the routine way. In bipolar mode, the surgical

approach determines the arrangement of the electrode arrays within the

cochlea and thus which channels can be used. After setting the T- and C-levels,

equalize the recipient’s perception of loudness for each channel.

Determining Appropriate ‘Electrode-to-Channel’ Allocation

If the electrode arrays have been inserted in the standard way (basal array

into the basal turn and apical array into the second turn of the cochlea), the

implant can be programmed like a standard Nucleus 24. If the electrode arrays

have been interchanged or if another surgical approach has been carried out,

one or both of the electrode arrays will need to be given a different ‘electrode-

to-channel’ order to maintain tonotopicity. Electrode array location (base or

apex) and direction (standard or retrograde) may be ascertained by performing

an x-ray. Alternatively, the Sweep command may be used whilst asking the

recipient to report on the subjective pitch order. A signiﬁcant pitch difference

should exist between the apical and basal array, and between the ends of each

individual array. Note that pitch differences between electrodes in the apex of

the cochlea are generally less than those in the base.

To ascertain electrode direction (standard or retrograde):

1. Sweep across all electrodes in the apex. In a standard insertion, electrode

pitch should decrease from electrode 12 to electrode 22. A retrograde

insertion will have the opposite pitch order.

2. Sweep across all electrodes in the base. In a standard insertion, electrode

pitch should decrease from electrode 1 to electrode 11. A retrograde

insertion will have the opposite pitch order.

1 2 ... 70 71 72 73 74 75 76 77 78

Sem comentários

Cochlear SPrint Sound Processor Informações Técnicas Página 75