Cochlea-Implantation: Bestimmung der Cochlear Duct Length (CDL)

Bei Cochlea-Implantationen gewinnt die personalisierte Versorgung zunehmend an Bedeutung. Die Wahl einer für den individuellen Patienten passenden Elektrode könnte das Sprachverstehen verbessern. Die Messung der cochleären Länge ist dabei wichtig: präoperativ für die Wahl der geeigneten Elektrodenlänge und postoperativ, um die korrekte Elektrodenlage zu kontrollieren und ein „anatomisches“ Fitting der Elektrodenkontakte zu ermöglichen.

Abstract

Personalized care in the context of cochlear implantation is becoming increasingly important. Choosing the right electrode could improve speech understanding. The measurement of the cochlear length plays an important role: preoperatively, in order to select a suitable electrode length; postoperatively, on the one hand to check the correct electrode position, on the other hand to enable anatomically based fitting of the electrode contacts. Of the various possible localizations of the CDL measurements within the cochlear turns, the one on the organ of Corti (CDL_OC) is the most frequently used and clinically most important. In the CDL measurement, a direct and indirect evaluation can be distinguished. There is also the possibility of reconstructing and measuring the CDL in 3D and calculating it mathematically, e.g. using spiral equations. In this context, measurements based on radiological imaging are gaining increasing importance. Therefore, if there is the possibility of performing higher-resolution imaging, this should be strived preoperatively in order to enable the most precise possible procedure and thus a good outcome. Otological planning software can help to create an interface between new findings regarding CDL measurement and higher-resolution imaging for an individualized cochlear implantation.

Kernaussagen

• Von den verschiedensten möglichen Lokalisationen der CDL-Messung innerhalb der cochleären Windungen wird diejenige am Corti-Organ am häufigsten verwendet und ist klinisch am bedeutendsten.

• Bei der CDL-Messung lassen sich die direkte und die indirekte Evaluation unterscheiden. Zusätzlich gibt es die Möglichkeit, die CDL in 3D zu rekonstruieren und zu vermessen sowie sie mathematisch z.B. über Spiralgleichungen zu berechnen.

• Die Längenreihenfolge der CDL lautet CDL_SG < CDL_OC < CDL_BM < CDL_LW.

• Wenn die Möglichkeit zur Durchführung von höher auflösender Bildgebung besteht, sollte diese präoperativ angestrebt werden, um ein möglichst präzises Vorgehen und damit ein optimiertes Ergebnis zu ermöglichen.

• Eine otologische Planungssoftware kann dazu verwendet werden, präoperativ die individuelle cochleäre Anatomie zu bestimmen und hierauf basierend eine geeignete Elektrode auszuwählen.

• Eine postoperative Bildgebung sollte im Erwachsenenalter stets durchgeführt werden, um die korrekte Lage und hierbei insbesondere die intracochleäre Lokalisation aller Kontakte zu kontrollieren.

• Ein anatomisch basiertes Fitting der Cochlea-implantierten Patienten wird das Hörempfinden in Zukunft mit hoher Wahrscheinlichkeit weiter verbessern.

• Das Wissen über die cochleäre Anatomie wird nicht zuletzt durch immer höher auflösende Bildgebungsmöglichkeiten wie die Synchrotron-Radiation-Phase-Contrast-Bildgebung weiter vorangetrieben werden.

Schlüsselwörter

Cochleäre Längenmessung - otologische Planungs-Software - Flat-Panel Volume CT - hochauflösende Bildgebung

Keywords

Cochlear Length Measurement - Otological Planning Software - Flat-Panel Volume CT - High Resolution Imaging

Publication History

Article published online:
02 May 2022

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