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To investigate electrically evoked auditory cortical responses (eACR) elicited from the stimulation of intracochlear electrodes based on individually fitted stimulation parameters in cochlear implant (CI) users. An eACR setup based on individual fitting parameters is proposed. A 50-ms alternating biphasic pulse train was used to stimulate apical, medial, and basal electrodes and to evoke auditory cortical potentials (N1-P2 complex). The eACR setup proposed was validated with 14 adult CI users. Individual and grand-average eACR waveforms were obtained. The eACR amplitudes were lower in the basal than in the apical and medial regions. Earlier N1 latencies were found in CI users with lower maximum comfortable loudness levels and shorter phase duration in response to apical stimulation, while medial and basal stimulation resulted in earlier N1 latencies and larger N1-P2 amplitudes in users with longer CI experience. eACR could be elicited by direct intracochlear stimulation using individual fitting parameters with a success rate of 71%. The highest cortical peak-to-peak amplitudes were obtained in response to apical stimulation. Unlike the P2, the N1 component appeared to be a consistent cortical potential to determine eACR and gain knowledge of the auditory processing beyond the cochlea in CI users. HighlightseACR can be elicited through direct stimulation of intracochlear electrodes.Stimulation of apical and medial regions yielded the highest N1-P2 amplitudes.CI users with lower maximum comfortable loudness levels had shorter N1 latencies during apical stimulation.The present dataset of mainly well-performing CI users suggests better cortical processing, that is, higher amplitudes and shorter latencies of N1.The N1 potential appears a more consistent and reliable potential than the P2 to determine eACR responses in CI users.

Objectives To perform a radio‐anatomical evaluation of the nasal cavity floor free mucosal graft (endonasal extended mucoplasty, EEM) to repair mucosal defects after an extended ethmoid‐sphenoidotomy. Methods A human cadaveric study (radiological and anatomical dissection) and an in vivo study in surgical patients with CRSwNP were performed. The EEM areas were compared between 3D reconstruction from CT scans and anatomical/surgical dissections, both in cadaver specimens and in patients. Feasibility was assessed by correlation between the EEM area on CT scans and when harvested in cadavers and when grafted in patients. Usefulness was assessed by the degree of coverage of the EEM in the surface exposed after an extended ethmoid‐sphenoidotomy. Both feasibility and usefulness were assessed in cadaveric specimens (n = 15) and patients (n = 4). Results Fifteen cadaveric specimens and 4 patients with bilateral CRSwNP were included. The mean (SD) areas obtained in the cadaveric radiological and anatomical studies were 9.44 (2.07) cm2 and 8.03 (1.36) cm2, respectively (intraclass correlation coefficient 0.59, moderate correlation), and in 3D reconstruction for operated patients were 10.32 (0.98) cm2 and 11.27 (2.44) cm2, respectively. The coverage of the ethmoidal roof in the cadaveric dissection study was 100%, from the anterior ethmoidal artery to the posterior ethmoidal artery, covering the planun sphenoidale up to 75% in the case series. In 87.5% of the cases, up to 50% of the papiracea lamina was covered. Conclusion The EEM have shown to be a feasible and useful grafting technique to repair skull base defects after performing an extended ethmoid‐sphenoidotomy during surgery for CRSwNP. Level of Evidence NA.