Electrocochleography in children with auditory synaptopathy/neuropathy: Diagnostic findings and characteristic parameters. Issue 2 (February 2015)

• Record Type: Journal Article
• Authors: Stuermer, Konrad Johannes; Beutner, Dirk; Foerst, Astrid; Hahn, Moritz; Lang-Roth, Ruth; Walger, Martin
• Is Part Of: International journal of pediatric otorhinolaryngology. Volume 79:Issue 2(2015:Feb.)
• Page Start: 139
• Page End: 145
• Publication Date: 2015-02
• Subjects: Otolaryngology -- Periodicals; Pediatrics -- Periodicals; Otolaryngology -- Periodicals; Pediatrics -- Periodicals; Oto-rhino-laryngologie -- Périodiques; Pédiatrie -- Périodiques; 618.9209751
• DOI: 10.1016/j.ijporl.2014.11.025
• Languages: English
• ISSNs: 0165-5876

Abstract

<abstract abstract-type="author" id="abs0005"> <title id="sect0005">Abstract</title> <sec> <title id="sect0010">Introduction</title> <p id="spar0005">The early diagnosis of AS/AN in children remains challenging because it exclusively relies on the detection of OAE and/or CM, while ABR are pathologically changed or missing.</p> <p id="spar0010">The aim of our study was to ensure the diagnosis of AS/AN, demarcate it to an outer hair cell damage and possibly differentiate between pre- and postsynaptic pathologies.</p> </sec> <sec> <title id="sect0015">Methods</title> <p id="spar0015">We retrospectively evaluated the transtympanic ECochG results of ten children with AS/AN and compared them to a matched group with SNHL and without any signs of AS/AN. We analyzed the thresholds, latencies and – as a new parameter – the amplitude ratio between CAP and SP.</p> </sec> <sec> <title id="sect0020">Results</title> <p id="spar0020">CM and SP thresholds were significantly lower than CAP thresholds in AS/AN patients and significantly lower than SP and CM thresholds in SNHL patients with comparable CAP thresholds. The CAP/SP ratio of amplitudes in SNHL children was more than three times (significantly) higher than in AS/AN children. The cutoff value was set at 1.0 in order to differentiate between both groups with a 80–90% sensitivity and specifity.</p> <p id="spar0025">It was not possible to differentiate between a pre- and postsynaptic type of AS/AN in our collective.</p> </sec> <sec> <title id="sect0025">Summary and conclusion</title> <p id="spar0030">The ECochG can add valuable information for a precise differential diagnosis of AS/AN, especially in babyhood. We identified the CAP/SP ratio as a new parameter for differentiation between AS/AN and SNHL. When the CAP/SP ratio falls below 1.0, patients can be diagnosed AS/AN with high specificity and sensitivity. Significantly smaller SPL are needed to evoke SP and CM in the AS/AN group, thus showing the preserved hair cell function.</p> </sec> </abstract>