Implicit Neural Representations for Breathing-compensated Volume Reconstruction in Robotic Ultrasound

Ultrasound (US) imaging is widely used in diagnosing and staging abdominal diseases due to its lack of non-ionizing radiation and prevalent availability. However, significant inter-operator variability and inconsistent image acquisition hinder the widespread adoption of extensive screening programs. Robotic ultrasound systems have emerged as a promising solution, offering standardized acquisition protocols and the possibility of automated acquisition. Additionally, these systems enable access to 3D data via robotic tracking, enhancing volumetric reconstruction for improved ultrasound interpretation and precise disease diagnosis.However, the interpretability of 3D US reconstruction of abdominal images can be affected by the patient’s breathing motion. This study introduces a method to compensate for breathing motion in 3D US compounding by leveraging implicit neural representations. Our approach employs a robotic ultrasound system for automated screenings. To demonstrate the method’s effectiveness, we evaluate our proposed method for the diagnosis and monitoring of abdominal aorta aneurysms as a representative use case.Our experiments demonstrate that our proposed pipeline facilitates robust automated robotic acquisition, mitigating artifacts from breathing motion, and yields smoother 3D reconstructions for enhanced screening and medical diagnosis.

I. Introduction

Medical ultrasound (US) is widely employed in clinical settings to diagnose conditions of internal tissues and organs. Its real-time imaging offers clinicians instant feedback. In comparison to other imaging methods like X-ray or CT, US presents several advantages: it’s radiation-free, portable, and cost-effective [1]. This, combined with its high soft-tissue contrast, ensures both safety and efficiency in patient care [2]. Ultrasound has become an essential tool for screening and monitoring of the abdominal region [3], [4]. In particular, for individuals aged 50 and above, routine US screening of aorta is recommended, as they might be at risk of developing aneurysms while being asymptomatic. Abdominal Aortic Aneurysm (AAA) is a condition marked by an enlargement in the aorta, which can lead to serious health implications if left untreated [5]. If an enlargement is detected, the frequency of follow-up screens increases based on its growth rate, ensuring timely interventions [6]. Consistent ultrasound screenings have shown a significant reduction of premature death from AAA in men aged 65 and older [7]. The primary goal of these screenings is to accurately measure and assess the aneurysm’s size and dimensions.