Klassifikation der Bandscheibendegeneration des Hundes in der nativen Computertomographie und der Hochfeld-Magnetresonanztomographie

Zusammenfassung

Gegenstand und Ziel: Die Klassifikation der kaninen Bandscheibendegeneration in der Magnetresonanztomographie ist in der Literatur beschrieben, während für die computertomographische Untersuchung kaniner Bandscheibenveränderungen bisher kein etabliertes Klassifikationssystem existiert. Da die Computertomographie ein häufig genutztes bildgebendes Verfahren in der Tiermedizin darstellt, war Ziel dieser Studie, ein derartiges Klassifikationssystems zu erstellen und zu validieren. Als vergleichende Methode stand eine T2-gewichtete magnetresonanztomographische Untersuchung zur Verfügung. Material und Methoden: Die computertomographische und magnetresonanztomographische Untersuchung von 43 Hunden ergab Bilddatensätze von 144 Bandscheiben. Diese Datensätze wurden verblindet, randomisiert und jeweils zweimal von drei Gutachtern beurteilt. Der Bewertung computertomographischer Datensätze lag das selbst entwickelte Klassifikationssystem zugrunde, während für die magnetresonanztomographischen Datensätze das Klassifikationssystem nach Pfirrmann angewendet wurde. Die Intra-und Interobserver-Übereinstimmung wurde mittels Statistical Analysis Software (SAS) bestimmt. Ergebnisse: Die Intra-und Interobserver-Übereinstimmung des Klassifikationssystems nach Pfirrmann (D-Werte 0,58–0,77) und des selbst entwickelten Klassifikationssystems (D-Werte 0,60–0,81) waren überwiegend gut. Zwischen den beiden Klassifikationssystemen ergab sich eine geringe Übereinstimmung (D = 0,26–0,29). Schlussfolgerung undklinische Relevanz: Eine zuverlässige Bewertung der Bandscheibendegeneration in der Computertomographie ist mit dem selbst entwickelten Klassifikationssystem möglich. Somit lassen sich zusätzliche Informationen für Diagnose und Prognose gewinnen. Die Computertomographie erfasst degenerative Veränderungen allerdings erst in einem fortgeschritteneren Stadium als die Magnetresonanztomographie.

Summary

Objective Although the classification of canine intervertebral disc degeneration using magnetic resonance imaging (MRI) has been described in the literature, there is no such classification using computed tomographic imaging. Because computed tomography (CT) is a frequently used diagnostic imaging tool in veterinary medicine, the aim of this study was the introduction and validation of such a scoring system. T2-weighted magnetic resonance images were available for comparative analysis. Material and methods: A total of 43 dogs were examined using CT and MRI. Image data records of 144 intervertebral discs were blinded, randomized and evaluated twice by three observers. CT data were analyzed using a self-developed scoring system, while MRI data sets were evaluated using the Pfirrmann scoring system. Intra-and interobserver agreement were determined using Statistical Analysis Software (SAS). Results Intra-and interobserver agreement were mostly substantial in the Pfirrmann (0.58–0.77) and self-developed (0.60–0.81) scoring systems. A slight agreement was found between both classification systems (D scores 0.26–0.29). Conclusion and clinical relevance: The self-developed scoring system allows a reliable assessment of canine intervertebral disc degeneration using CT imaging. Therefore, further diagnostic and prognostic information can be obtained. Degenerative changes in the intervertebral discs could be identified at an earlier stage when using MRI in comparison with CT.

Schlüsselwörter

Bandscheibenvorfall - Verkalkung - kanin - bildgebende Diagnostik - Klassifikationssystem

Key words

Intervertebral disc herniation - calcification - canine - diagnostic imaging - scoring system

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