Different Evaluation Strategies of Oncological CT Examinations with Regard to Professional Experience: A Clinical Study Using Eye-tracking

Abstract

Purpose

Contrast-enhanced CT is the standard imaging technique in oncological objectives. Rates of missed pathologies depend on work experience of the respective radiologists. Thus the aim of this study is to analyze the eye movements of professionals while reading CT images in order to evaluate whether the eye-fixation patterns and search strategies of experienced radiologists could explain higher detection rates of pathologies and whether such patterns can be learned.

Materials and Methods

Anonymized images of 10 patients were presented to three medical students and six radiologists with different levels of work experience. During image analysis, ocular fixation positions were recorded using an eye-tracking software tool. The CT scans were analyzed retrospectively, considering the individual course of disease with the issue of successful detection of all pathologies. Visual attention and dwell time of ocular fixation on clinically important abnormalities or areas with pathological findings, general search patterns, and time efficiency were assessed. For statistical analysis, interobserver variability and accuracy of lesion detection were evaluated taking into account individual experience.

Results

The results revealed that observer sensitivity depends on work experience due to a more systematic order of inspection and a well-known course of disease, e.g. in case of metastatic spread. The areas of missed pathologies mostly included secondary findings. Inexperienced readers changed the stratification considerably more often and required more time for reporting or detecting pathologies.

Conclusions

Our results suggest that experienced radiological physicians reduce their amount of missed findings by looking more systematically at images and by applying a more targeted inspection of clinically important regions.

Key Points

• CT interpretation by radiology residents is faster and less error-prone compared to postgraduate residents

• systematic image analysis is trainable

• engrams tend to be acquired through experience

Citation Format

• Kluge S, Schülke C, Ites HC et al. Different Evaluation Strategies of Oncological CT Examinations with Regard to Professional Experience: A Clinical Study Using Eye-tracking. Fortschr Röntgenstr 2024; DOI 10.1055/a-2452-2180

Zusammenfassung

Ziel

Die kontrastverstärkte CT ist das Standardbildgebungsverfahren bei onkologischen Zielsetzungen. Die Rate der übersehenen Pathologien hängt von der Berufserfahrung der jeweiligen Radiologen ab. Ziel dieser Studie ist es daher, die Augenbewegungen von Fachleuten beim Lesen von CT-Bildern zu analysieren, um festzustellen, ob die Augenfixationsmuster und Suchstrategien erfahrener Radiologen höhere Entdeckungsraten von Pathologien erklären können und ob solche Muster erlernt werden können.

Materialien und Methoden

Anonymisierte Bilder von 10 Patienten wurden 3 Medizinstudenten und 6 Radiologen mit unterschiedlicher Berufserfahrung vorgelegt. Während der Bildanalyse wurden die Fixationspositionen der Augen mit einer Eyetracking-Software aufgezeichnet. Die CT-Scans wurden retrospektiv unter Berücksichtigung des individuellen Krankheitsverlaufs mit der Fragestellung der erfolgreichen Erkennung aller Pathologien analysiert. Die visuelle Aufmerksamkeit und die Verweildauer der Augenfixation auf klinisch wichtige Anomalien oder Bereiche mit pathologischen Befunden, allgemeine Suchmuster und Zeiteffizienz wurden bewertet. Für die statistische Analyse wurden die Interobserver-Variabilität und die Genauigkeit der Läsionserkennung unter Berücksichtigung der individuellen Erfahrung bewertet.

Ergebnisse

Die Ergebnisse zeigten, dass die Sensitivität des Beobachters von der Berufserfahrung abhängt, da die Inspektion systematischer abläuft und der Krankheitsverlauf bekannt ist, z.B. im Falle einer metastatischen Ausbreitung. Zu den übersehenen Pathologien gehörten meist Sekundärbefunde. Unerfahrene Beobachter änderten die Schichtebenen wesentlich häufiger und benötigten mehr Zeit für die Meldung oder Entdeckung von Pathologien.

Schlussfolgerungen

Unsere Ergebnisse deuten darauf hin, dass erfahrene Radiologen die Zahl der übersehenen Befunde verringern, indem sie die Bilder systematischer betrachten und eine gezieltere Inspektion der klinisch wichtigen Regionen vornehmen.

Kernaussagen

• schnellere und weniger fehleranfälligere CT-Interpretation durch radiologische Fachärzte gegenüber Weiterbildungs-Assistenzärzten

• systematische Bildanalyse trainierbar

• Engramme eher erworben durch Erfahrung

Keywords

abdomen - METHODS & TECHNIQUES - diagnostic radiology - education - observer performance - eye tracking

Publication History

Received: 10 April 2024

Accepted after revision: 21 October 2024

Article published online:
12 November 2024

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