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Background: In most cases, intralabyrinthine schwannoma (ILS) occurs in patients with unilateral hearing deterioration or neurofibromatosis type II (NF II). The pattern of localization of these tumors varies but mostly affects the cochlea. Extirpation of the cochlear schwannoma, if hidden by the cochlea modiolus, is difficult under the aspect of complete removal. Therefore, a tissue removal device (TRD) was designed and tested in temporal bones. The principle of handling the new device is a pushing and pipe cleaner handling inside the cochlea. This present study aimed to describe the first in vivo experience with the newly developed TRD for removing cochlear intralabyrinthine schwannomas. Methods: In three patients, the TRD was used for the tumor removal of cochlear schwannomas. In two patients with a cochlear schwannoma in combination with a cochlea implantation and one patient suffering from NF II, a cochlear schwannoma was removed with the TRD. The access was performed with a posterior tympanotomy, an enlarged round window approach and an additional second turn access. The device was inserted and extracted gradually from the second turn access until the rings were visible in the second turn access. By pushing and pipe cleaner handling, the tumors were removed. An MRI control was performed on the day postoperatively with a T1 GAD sequence. Results: Tumor removal with the TRD was performed in a 15-min procedure without any complications. An MRI control confirmed complete removal on the postoperative day in all cases. Conclusions: In vivo handling of the device confirmed straightforward handling for the tumor removal. MRI scanning showed complete removal of the tumor by the TRD. [ABSTRACT FROM AUTHOR]

Introduction Cochlear implant (CI) magnets and surgical techniques (e.g., positioning) have made an impact on the relationship between CI and magnetic resonance imaging (MRI) by solving the problem of pain and artifact. Recent investigations displayed the possibility to evaluate the CI electrode position by MRI in vivo. However, further improved perceptual quality is needed to allow an improved evaluation of the electrode. Aims The aim of this study was to assess a cochlear model for the examination of CI electrode pattern and MRI sequences in vitro. Materials and Methods We investigated CI electrodes in a fluid-filled three-dimensional artificial scala tympani model combined with a fluid package in a 3T MRI scanner. Different high-resolution T2 sequences (0.6–0.2 mm voxel size) were used for the visual electrode pattern evaluation for finding an optimized sequence. Results Artificial models can be used to evaluate MRI characteristics of CI electrodes. In our scanner configuration, a 0.3 mm voxel and 0.9 mm slice thickness sequence showed the best compromise between resolution and scanning time. Conclusion and Significance MRI model-based testing can be performed in vitro to evaluate CI electrodes' pattern and to optimize sequences. An MRI model is a tool for in vitro testing of MRI sequences and might help for future in vivo applications. [ABSTRACT FROM AUTHOR]