Cochlear hair cells are inhibited by cholinergic efferent neurons. The acetylcholine (ACh) receptor of the hair cell is a ligand-gated cation channel through which calcium enters to activate potassium channels and hyperpolarize the cell. It has been proposed that calciuminduced calcium release (CICR) from a near-membrane postsynaptic store supplements this process. Here, we demonstrate expression of type I ryanodine receptors in outer hair cells in the apical turn of the rat cochlea. Consistent with this finding, ryanodine and other store-active compounds alter the amplitude of transient currents produced by synaptic release of ACh, as well as the response of the hair cell to exogenous ACh. Like the sarcoplasmic reticulum of muscle, the "synaptoplasmic" cistern of the hair cell efficiently couples synaptic input to CICR.
Objectives/Hypothesis
Evaluate technical success, tolerability, and safety of lidocaine iontophoresis and tympanostomy tube placement for children in an office setting.
Study Design
Prospective individual cohort study.
Methods
This prospective multicenter study evaluated in‐office tube placement in children ages 6 months through 12 years of age. Anesthesia was achieved via lidocaine/epinephrine iontophoresis. Tube placement was conducted using an integrated and automated myringotomy and tube delivery system. Anxiolytics, sedation, and papoose board were not used. Technical success and safety were evaluated. Patients 5 to 12 years old self‐reported tube placement pain using the Faces Pain Scale–Revised (FPS‐R) instrument, which ranges from 0 (no pain) to 10 (very much pain).
Results
Children were enrolled into three cohorts with 68, 47, and 222 children in the Operating Room (OR) Lead‐In, Office Lead‐In, and Pivotal cohorts, respectively. In the Pivotal cohort, there were 120 and 102 children in the <5 and 5‐ to 12‐year‐old age groups, respectively, with a mean age of 2.3 and 7.6 years, respectively. Bilateral tube placement was indicated for 94.2% of children <5 and 88.2% of children 5 to 12 years old. Tubes were successfully placed in all indicated ears in 85.8% (103/120) of children <5 and 89.2% (91/102) of children 5 to 12 years old. Mean FPS‐R score was 3.30 (standard deviation [SD] = 3.39) for tube placement and 1.69 (SD = 2.43) at 5 minutes postprocedure. There were no serious adverse events. Nonserious adverse events occurred at rates similar to standard tympanostomy procedures.
Conclusions
In‐office tube placement in selected patients can be successfully achieved without requiring sedatives, anxiolytics, or papoose restraints via lidocaine iontophoresis local anesthesia and an automated myringotomy and tube delivery system.
Level of Evidence
2b Laryngoscope, 130:S1–S9, 2020
Previous studies have shown equivalent effectiveness between these two procedures; our study suggests decreased cost and resource utilization with partial tonsillectomy through reduced operative and PACU times and number of postoperative admissions and emergency department visits. As in all retrospective reviews, the findings are potentially confounded by unmeasured variables, including patient and demographic factors.
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