Exploring the Zero-Shot Capabilities of the Segment Anything Model (SAM) in 2D Medical Imaging: A Comprehensive Evaluation and Practical Guideline

Segmentation in medical imaging plays a crucial role in diagnosing, monitoring, and treating various diseases and conditions. The current landscape of segmentation in the medical domain is dominated by numerous specialized deep learning models fine-tuned for each segmentation task and image modality. Recently, the Segment Anything Model (SAM), a new segmentation model, was introduced. SAM utilizes the ViT neural architecture and leverages a vast training dataset to segment almost any object. However, its generalizability to the medical domain remains unexplored. In this study, we assess the zero-shot capabilities of SAM 2D in medical imaging using eight different prompt strategies across six datasets from four imaging modalities: X-ray, ultrasound, dermatoscopy, and colonoscopy. Our results demonstrate that SAM's zero-shot performance is comparable and, in certain cases, superior to the current state-of-the-art. Based on our findings, we propose a practical guideline that requires minimal interaction and yields robust results in all evaluated contexts.