1.
Round window /Cochleostomy

2.
Device Positioning device away from processor receiver/stimulator oriented differently in infants

3.
Displacement Force Calculation AL R P mg

4.
Tie-down – Devices with and withouta Pedestal the bed the device tied in

5.
Visualizing the Round Window key  to cochleostomy placement is finding landmarks every time  most important landmark is the round window

6.
Visualizing the Round Window hand position differs on the left side care with stapes tendon

7.
Round Window always present round window overhang relationship to oval window is constant jugular bulb stapes tendon Cavity Common Right Ear rolls away in jugular bulb anomalies

8.
Round Window cochleostomy  direction  entry into the scala tympani

9.
Cochleostomy vs. Round Window bone in round window steeper angle at first turn contact hard to pack/seal right ear bone in hook region

10.
Cochleostomy vs. Round Window bone in round right ear window steeper angle at first turn contact hard to pack/seal

11.
Cochleostomy vs. Round Window bone in round window steeper angle at first turn contact hard to pack/seal

12.
Preparing the Cochleostomy anterior to the round window as inferior as possible look often

13.
Cochleostomy with curved burs Curved HS Neurotology Burs Coolant Wrap

14.
Opening the Cochlea pick used in “soft” technique hearing preservation

15.
Drilling the Cochleostomy right ear target is scala tympani enter cochlea expand in anterior and inferior direction slow speed drilling

16.
Drilling the Cochleostomy right ear target is scala tympani

17.
Drilling the Cochleostomy slow speed drilling round off anterior and inferior edges (electrode is 0.8 mm) flush out bone dust

18.
Ideal Cochlear Entry Point

19.
Access into Scala Tympani scala vestibuli modiolus scala tympani Photo courtesy CRC for Cochlear Implant and Hearing Aid Innovation, MELBOURNE

20.
CASISTICA CLINICAmarzo 2003 – dicembre 2011N° SEX AGE RANGE TYPE I.C. Cochlear312 148m 156f 11m. - 16aa Med- El AB MXM

21.
Abnormal Cochleae 25% of anomalous cochleae have technical challenges at OR  gushers  anomalous VII n. anatomy  problematic exposure

22.
Perilymph Gushers enlarged vestibular aqueduct (VAE)

23.
Perilymph Gushers enlarged vestibular aqueduct (VAE) common cavity deformity

24.
Perilymph Gushers enlarged vestibular aqueduct (VAE) common cavity deformity incomplete partition (IP-1)

25.
Facial Nerve Anomalies common (14%) and associated with:  CC and HC  anomalous stapes  nerve can split proximally facial nerve monitor essential

26.
Problematic Anatomyhypoplastic cochleaanteriorly displaced CN VIIprominent sinus pericrani

27.
Re-implantation device failure device infection  (leave array in cochlea if possible)

28.
Re-implantation tips  be prepared to drill around cochleostomy  insert new array immediately old array removed  straight array narrower but more flexible

29.
Choice of electrode array IndicationsOptions general use, atraumatic Pre-curved AOS insertion incomplete partition Straight hearing preservation Short apical stimulation Long ossified cochleae Double or split

30.
Conclusion keys to success are:  appropriate selection of the patient  fixation of the receiver stimulator  identification of landmarks for round window/cochleostomy  care with abnormal cochleae  appropriate selection of the electrode

31.
CONCLUSIONS 2 CI is generally possible in cases with inner ear malformations Variable results (neural function) generally satisfactory results Facial nerve anomalies Surgical issues •surgical access Cochlear anomalies •CSF gusher (difficult to radiologically predict) •type of array •array placement misplacement in the IAC (++IP I, IP III, CC, CH) Programming difficulties / facial nerve electrical stimulation Fenestral CSF fistula (++)Higher risk of post-op. meningitis CSF fistula at cochleostomy site (--)

32.
 Cochlear nerve aplasia-hypoplasia is not uncommon(unilateral ++)Cochlear nerve aplasia associated to a normal labirynth is possibleA severely narrowed IAC (2 mm) indicates a severe hypoplasia of the cochleo-vestibularnerve, but not a sure absence of the cochlear nerve (if the cochlear duct is present and thelabirynth is malformed, the possibility of a functioning cochlear nerve is higher) A normal IAC does not garantee the presence of a normal cochleo-vestibular nerve(unilateral cases, parasagittal reconstructions) The outcome after CI in pts with aplasia-hypoplasia of the cochlear n. are generally scarce

33.
Azienda Ospedaliera di Rilievo Nazionale Santobono – Pausilipon NAPOLI Thank You !!!