Three-dimensional endoanal ultrasound
3D endoanal ultrasound (3D EAUS) is a key diagnostic tool for evaluating pelvic floor disorders, providing detailed insight into the function of the anal sphincters, mucosa, and surrounding structures, including the bladder, and in women, the vagina. This advanced imaging technique is particularly useful in diagnosing anal fistulas, anal incontinence, sphincter defects, and in assessing the stage of low rectal and anal canal tumors.
Why is three-dimensional endoanal ultrasound used and how does it work?
3D EAUS provides high-resolution, three-dimensional images of the anal canal and surrounding structures. The procedure uses a high-frequency probe, typically 13-20 MHz, which captures a series of 2D cross-sections. These images are then reconstructed into a 3D volume, known as a “cube,” allowing the physician to navigate through the tissue in all directions, accurately analyzing the anatomy and any pathological changes. Visualized structures include the internal and external anal sphincters, mucosa, submucosa, all pelvic floor muscles, perirectal fat, and when needed the vagina and bladder.
3D EAUS enables precise planning of surgical and conservative interventions. Images of each patient can be stored for later comparison before and after therapy. The procedure is also more accessible and practical for intraoperative use compared to magnetic resonance imaging (MRI).
What are the key benefits for the patient?
The main advantages of 3D EAUS include:
- High-resolution and precise diagnostics
- Minimal discomfort for the patient
- Non-invasiveness and improved treatment outcomes
This technique is an essential tool for accurately assessing pelvic floor disorders, providing better understanding of complex anatomy and pathological changes, and improving diagnostic accuracy and patient outcomes.
