2.1

Population

All research was approved by the University of Mississippi institutional review board. Between April 2003 and October 2014, 156 children of varying demographics and SNHL etiologies underwent placement of 248 cochlear implants at our institution. Patients receiving traditional larger incision surgery or reimplantations of devices placed at other institutions were excluded. All operations were performed by a single attending surgeon (JDC) and resident assistant. Patients receiving bilateral implantation were classified as two distinct ears.

2.2

Surgical technique

A minimally invasive approach similar to that outlined by O’Donoghue was utilized . Monitoring leads for the Medtronic NIM Response® (Medtronic, Inc., Minneapolis, MN) are placed into the orbicularis oris and oculi muscles bilaterally. A small amount of hair is shaved behind each ear over implantation site. A four cm vertical incision site is marked posterior to the postauricular sulcus and infiltrated with local anesthetic with epinephrine. Templates are used to mark the position of the external processor and internal receiver. In cases of bilateral simultaneous implantation, the entire head is prepped preoperatively.

An incision is made and carried to level of the mastoid periosteum. A posteriorly based rectangular periosteal flap, essential for complete periosteal closure, is designed and elevated. A pocket to accommodate the receiver is elevated and a small recess is drilled into the skull for placement. A limited mastoidectomy is performed in the usual fashion. Since it was released the senior author has used the Visao® drill (Medtronic, Inc., Jacksonville, FL) with curved burs for the facial recess and cochleostomy ( Fig. 1 ). These burs have a non-rotating shaft that virtually eliminates the risk of heat transfer to the nerve and the curve allows easier middle ear visualization. The round window niche is then drilled and the scala tympani is entered through the round window or a separate cochleostomy. Overlying skin is retracted, and tie down sutures are secured at the hub of the implant ( Fig. 2 ). The facial recess and mastoid are then packed with gelfoam soaked in ofloxacin. An intraoperative x-ray is gathered to assure adequate electrode positioning. Glasscock® (Oto-Med, Inc., Lake Havasu City, AZ) ear dressings are used instead of pressure dressings. Generally, the patient is discharged the same day if the child is over 12 months and there are no other medical conditions that would warrant admission .

Drill. Example of drill entry into for the facial recess and cochleostomy (Figure 1). These curved burs have a non-rotating shaft that minimizes heat transfer and provides maximal visualization.

Retractors. Placement of retractors for easily visualization of cochlear implant hub.

2.3

Complication classification

Similar to the classification scheme offered in recent literature, postoperative complications were classified as either major or minor depending on extent of management . Minor complications were those that could be managed with outpatient therapy. Major complications were those considered to result in serious, potentially life-threatening conditions, such as those requiring intravenous (IV) antibiotics, or those requiring major surgical revision such as explantation or reimplantation. In cases of acute otitis media (AOM), which may or may not be related to the CI procedure, a post-operative timeframe of 30 days was set as the cutoff criteria to being attributed to a surgical complication. Additionally, complications were grouped according to time of presentation. Complications presenting within the first week were classified as immediate post-operative complications, those presenting from one week to 30 days early complications, and those presenting after 30 days delayed complications.

2.4

Tympanostomy tubes

Past surgical history was reviewed for tympanostomy tube placement. The patients were grouped accordingly to evaluate associations between tympanostomy tubes and post-operative complications of CI.

2.1

Population

All research was approved by the University of Mississippi institutional review board. Between April 2003 and October 2014, 156 children of varying demographics and SNHL etiologies underwent placement of 248 cochlear implants at our institution. Patients receiving traditional larger incision surgery or reimplantations of devices placed at other institutions were excluded. All operations were performed by a single attending surgeon (JDC) and resident assistant. Patients receiving bilateral implantation were classified as two distinct ears.

2.2

Surgical technique

A minimally invasive approach similar to that outlined by O’Donoghue was utilized . Monitoring leads for the Medtronic NIM Response® (Medtronic, Inc., Minneapolis, MN) are placed into the orbicularis oris and oculi muscles bilaterally. A small amount of hair is shaved behind each ear over implantation site. A four cm vertical incision site is marked posterior to the postauricular sulcus and infiltrated with local anesthetic with epinephrine. Templates are used to mark the position of the external processor and internal receiver. In cases of bilateral simultaneous implantation, the entire head is prepped preoperatively.

An incision is made and carried to level of the mastoid periosteum. A posteriorly based rectangular periosteal flap, essential for complete periosteal closure, is designed and elevated. A pocket to accommodate the receiver is elevated and a small recess is drilled into the skull for placement. A limited mastoidectomy is performed in the usual fashion. Since it was released the senior author has used the Visao® drill (Medtronic, Inc., Jacksonville, FL) with curved burs for the facial recess and cochleostomy ( Fig. 1 ). These burs have a non-rotating shaft that virtually eliminates the risk of heat transfer to the nerve and the curve allows easier middle ear visualization. The round window niche is then drilled and the scala tympani is entered through the round window or a separate cochleostomy. Overlying skin is retracted, and tie down sutures are secured at the hub of the implant ( Fig. 2 ). The facial recess and mastoid are then packed with gelfoam soaked in ofloxacin. An intraoperative x-ray is gathered to assure adequate electrode positioning. Glasscock® (Oto-Med, Inc., Lake Havasu City, AZ) ear dressings are used instead of pressure dressings. Generally, the patient is discharged the same day if the child is over 12 months and there are no other medical conditions that would warrant admission .

Drill. Example of drill entry into for the facial recess and cochleostomy (Figure 1). These curved burs have a non-rotating shaft that minimizes heat transfer and provides maximal visualization.

Retractors. Placement of retractors for easily visualization of cochlear implant hub.

2.3

Complication classification

Similar to the classification scheme offered in recent literature, postoperative complications were classified as either major or minor depending on extent of management . Minor complications were those that could be managed with outpatient therapy. Major complications were those considered to result in serious, potentially life-threatening conditions, such as those requiring intravenous (IV) antibiotics, or those requiring major surgical revision such as explantation or reimplantation. In cases of acute otitis media (AOM), which may or may not be related to the CI procedure, a post-operative timeframe of 30 days was set as the cutoff criteria to being attributed to a surgical complication. Additionally, complications were grouped according to time of presentation. Complications presenting within the first week were classified as immediate post-operative complications, those presenting from one week to 30 days early complications, and those presenting after 30 days delayed complications.

2.4

Tympanostomy tubes

Past surgical history was reviewed for tympanostomy tube placement. The patients were grouped accordingly to evaluate associations between tympanostomy tubes and post-operative complications of CI.