# Real-time Deformation of Soft Tissue Internal Structure with Surface Profile Variations using Particle System

## TL;DR

This paper presents a real-time method for simulating internal soft tissue deformation based on surface profile variations using a particle system, enabling efficient and mesh-free internal structure modeling during surgery.

## Contribution

The novel approach models internal tissue deformation in real-time with a particle system that does not require 3D mesh generation, reducing computational complexity.

## Key findings

- Handles up to 10,000 particles in 0.3 seconds
- Reduces computational burden with simplified calculations
- Does not require generating 3D meshes

## Abstract

Intraoperative observation of tissue internal structure is often difficult. Hence, real-time soft tissue deformation is essential for the localization of tumor and other internal structures. We propose a method to simulate the internal structural deformations in a soft tissue with surface profile variations. The deformation simulation utilizes virtual physical particles that receive interaction forces from the surface and other particles and adjust their positions accordingly. The proposed method involves two stages. In the initialization stage, the three-dimensional internal structure of the surface mesh is uniformly sampled using the particle expansion and attracting-repelling force models whilst simultaneously building the internal particle connections. In the simulation stage, under surface profile variations, we simulate the internal structural deformation based on a deformation force model that uses the internal particle connections. The main advantage of this method is that it greatly reduces the computational burden as it only involves simplified calculations and also does not require generating three-dimensional meshes. Preliminary experimental results show that the proposed method can handle up to 10,000 particles in 0.3s.