Using geometrically tailored dielectric pads enables high spatial resolution magnetic resonance imaging of the human inner ear at 7 T. The high spatial resolution improves the depiction of the fine inner ear structures, showing the benefit of magnetic resonance imaging at ultrahigh fields.

The HiFocus Mid-Scala (MS) electrode array has recently been introduced onto the market. This precurved design with a targeted mid-scalar intracochlear position pursues an atraumatic insertion and optimal distance for neural stimulation. In this study we prospectively examined the angular insertion depth achieved and speech perception outcomes resulting from the HiFocus MS electrode array for 6 months after implantation, and retrospectively compared these with the HiFocus 1J lateral wall electrode array. The mean angular insertion depth within the MS population (n = 96) was found at 470°. This was 50° shallower but more consistent than the 1J electrode array (n = 110). Audiological evaluation within a subgroup, including only postlingual, unilaterally implanted, adult cochlear implant recipients who were matched on preoperative speech perception scores and the duration of deafness (MS = 32, 1J = 32), showed no difference in speech perception outcomes between the MS and 1J groups. Furthermore, speech perception outcome was not affected by the angular insertion depth or frequency mismatch.

Cochlear size and morphology vary greatly and may influence the course of a cochlear implant electrode array during insertion and its final intra-cochlear position. Detailed insight into these variations is valuable for characterizing each cochlea and offers the opportunity to study possible correlations with surgical or speech perception outcomes. This study presents an automatic tracing method to assess individual cochlear duct shapes from clinical CT images. On pre-operative CT scans of 479 inner ears the cochlear walls were discriminated by interpolating voxel intensities along radial and perpendicular lines within multiplanar reconstructions at 1 degree intervals from the round window. In all 479 cochleas, the outer wall could be traced automatically up to 720 degrees. The inner wall and floor of the scala tympani in 192 cochleas. The shape of the cochlear walls were modelled using a logarithmic spiral function including an offset value. The vertical trajectories of the scala tympani exhibited a non-monotonous spiral slope with specific regions at risk for CI-related insertion trauma, and three slope categories could be distinguished. This presented automatic tracing method allows the detailed description of cochlear morphology and can be used for both individual and large cohort evaluation of cochlear implant patients.

BACKGROUND AND PURPOSE:In many centers, MR imaging of the inner ear and auditory pathway performed on 1.5T or 3T systems is part of the preoperative work-up of cochlear implants. We investigated the applicability of clinical inner ear MR imaging at 7T and compared the visibility of inner ear structures and nerves within the internal auditory canal with images acquired at 3T.

analysis. No correlation was present between the counts of herpesvirus-specific T cells and bacterial or fungal infections, possibly, as Th2 rather than Th1 T-cell response helps to curb bacterial infections.The major limitation of our study is the relatively low number of patients. Additionally, we selected patients who did not have GVHD on day 56 (as these patients would not be candidates for withdrawal of immunosuppressive drugs or donor lymphocyte infusion (DLI)), and excluded patients who developed second malignancy (as these patients are typically treated by modalities that alter their immunity). We did evaluate the counts of herpesvirus-specific T cells in the six patients excluded owing to second malignancy (mostly post transplant lymphoproliferative disorder (PTLD)), but did not show the data. All patients had a score of 0. Even if these patients were treated with preemptive treatment for relapse (that is, withdrawal of immunosuppression or DLI), they would likely benefit from the treatment, as withdrawal or decrease of immunosuppression or DLI are treatment options for PTLD.In conclusion, we have shown that herpesvirus-specific T cells can indeed be a surrogate marker of the GVL response in AML patients. The ability to predict patients with increased risk of relapse could lead to preemptive therapy, such as withdrawal of immunosuppression or DLI and reduction in relapse rates. However, preemptive therapy can have adverse effects. The ability to clearly distinguish between patients at high versus low risk of relapse is therefore essential. Our assay has shown a high sensitivity, however, a better specificity would be desirable for guiding preemptive treatment. Perhaps, if combining our assay with an assay of high specificity albeit poor sensitivity (for example, a minimal residual disease assay), the best prediction of relapse could be achieved. Future studies including a higher number of patients and performed prospectively are necessary to confirm the clinical utility of these assays. Conflict of interestThe authors declare no conflict of interest.