Konrad Johannes Stuermer

Objectives: To describe the long-term results of the titanium angular clip prosthesis 10 years after its initial description. Study Design: Clinical retrospective study. Setting: Tertiary referral center. Patients: Sixty three patients with isolated defects of the long process of the incus where the ossicular chain was reconstructed by a titanium angular clip prosthesis. Interventions: Therapeutic. Main Outcome Measures: The mean air-bone gap was calculated over the frequencies of 0.5, 1, 2, 3, and 4 kHz. Results: The placement of the prosthesis was straightforward in all patients, without any complication. During the first follow-up visit after 3 weeks (n = 61) the mean air-bone gap (ABG) was reduced by 10 dB HL, and from 24 dB HL preoperatively to 14 dB HL. At the long-term follow-up appointment—4 years after implantation (n = 29)—the mean ABG was still reduced by 8 dB HL, from a mean of 26 dB HL preoperatively to 18 dB HL. Conclusion: The use of the titanium angular clip prosthesis is a safe and reliable way to bridge an isolated erosion of the long process of the incus, leading to significant and long-lasting improvement of the ABG both in the short and long-term follow-up. A similarly large improvement of the sound transmission can be achieved both in patients with a Type A and a Type B/C tympanogram.

Objective: To examine the possible correlation between the loss of short-term residual hearing and vestibular function after cochlear implantation (CI). Study Design: Retrospective patient review. Setting: Academic tertiary referral center. Patients: One hundred twenty patients with normal vestibular function (VF) in the caloric testing and residual hearing (RH) at the frequencies 250, 500, and 1000 Hz on the surgery side between 2008 and 2016 were included in the study. Intervention: Primary CI on the first side via round window with a conventional full-length electrode. Main Outcome Measures: Changes of RH and VF 7 weeks after surgery were analyzed. Preservation of RH was defined as measurable postoperative thresholds at the frequencies 250, 500, and 1000 Hz in the pure-tone audiogram. Preservation of the VF after CI was assessed both by an absolute and relative threshold in the caloric testing. Results: Seven weeks after implantation, the preservation of RH was achieved in 52 (43.3 %) patients and the preservation of VF in 95 (79.2 %) patients on the operated side. There was no significant statistical correlation between these two parameters. Conclusion: The loss of RH was more than twice as frequent as the loss of VF. However, no statistical correlation between the failure of the two inner ear functions was found. The exact causes are still unknown, but our data could give an indication that there may be different underlying pathomechanisms.

The opening of the round window and the insertion of the electrode array into the scala tympani during cochlear implant surgery can lead to a pressure shock of the delicate inner ear structures. By filling the tympanic cavity with Ringer Solution during these surgical steps (underwater technique), the hydrostatic pressure of the fluid acts as a smooth pressure stabilizer, avoiding a pressure shock of the inner ear structures. The aim of this retrospective study was to present long-term results of this new method of cochlear implantation in underwater technique.

Objective: The individual outcome after cochlear implantation in children with auditory synaptopathy/neuropathy (AS/AN) is difficult to predict. A tool for preoperative assessment would be helpful for counseling parents. This study evaluates the outcome after CI in children with AS/AN and with sensorineural hearing loss (SNHL), and correlates it with the preoperative ECochG results in order to find specific parameters of prognostic value. Design: The improvement of auditory behavior after CI was retrospectively assessed using the LittlEARS questionnaire and quantified in a score (LS). This score was correlated with the CAP/SP ratio in the preoperative ECochG. The score was further correlated with the patient’s age six months following CI. Study sample: Nine children with AS/AN were compared to nine children with SNHL. Results: Both groups showed a significant improvement in LS following CI. There was a significant positive correlation between the CAP/SP ratio and the improvement in LS in all children. The correlation between age and LS was significantly negative in the SNHL group and positive in the AS/AN group. Conclusion: All children with AS/AN and SNHL benefit to a similar extent from CI. The preoperatively assessed CAP/SP ratio has a prognostic value for the development of auditory behavior following CI.

In carbon dioxide (CO₂) laser surgery of the larynx, the potentially dangerous combination of laser-induced heat in an oxygen-enriched atmosphere typically occurs when jet ventilation is used or due to an insufficiently blocked endotracheal tube. Until now, no limitations for safe oxygen concentrations or laser intervals have been established. The aim of this study was to investigate and quantify the factors that may contribute to an airway fire in laryngeal laser surgery. Fat, muscle and cartilage were irradiated with a CO₂ laser at 2, 4, 6 and 8 W in five different oxygen concentrations with and without smoke exhaustion. The time to ignition was recorded for each different experimental setup. Fat burnt fastest, followed by cartilage and muscle. The elevation of laser energy or oxygen concentration reduced the time to inflammation of any tissue. The elevation of oxygen by 10 % increases the risk of inflammation more than the elevation of laser power by 2 W. Under smoke exhaustion, inflammation and burning occurred delayed or were even inhibited at lower oxygen concentrations. Lasing in more than 50 % oxygen is comparatively dangerous and can cause airway fire in less than 5 s, especially when laser energies of more than 5 W are applied. In equal or lower than 50 % oxygen, an irradiation interval of 5 s can be considered a comparatively safe time limit to prevent inflammation in laryngeal laser surgery. Smoke exhaustion should always be applied.