CTfistulografie

CT fistulography is a radiologic technique in which contrast material is injected into a fistulous tract and multidetector CT is used to acquire cross-sectional images that delineate the tract’s course, its connections, and associated collections. The exam provides three-dimensional visualization of complex fistula networks and helps identify internal openings, secondary tracts, and abscess cavities. It is commonly employed for evaluating complex perianal fistulas and is also applicable to fistulas in other regions when detailed delineation is needed, particularly before surgical intervention or drainage procedures.

Technique involves cannulation of the fistulous opening or accessible tract under sterile conditions, followed by slow injection of a water-soluble iodinated contrast agent to opacify the tract. CT scanning is performed with thin slices, often with multiplanar and three-dimensional reconstructions. Delayed imaging may be used to permit contrast to fill occult branches or abscess cavities. The procedure may be preceded by antibiotics as indicated and requires informed consent regarding radiation exposure.

Advantages include high-resolution anatomic detail, precise tract mapping, rapid acquisition, and usefulness for preoperative planning. Limitations include radiation exposure, invasiveness from catheter placement, risk of iodinated contrast reaction, potential incomplete opacification of all branches, and sometimes limited soft-tissue contrast compared with MRI in certain settings.

CT fistulography is typically considered when detailed tract delineation is crucial for management, especially in complex fistulas where surgical planning depends on accurate mapping of all affected channels. It often complements MRI and conventional imaging in the broader evaluation of fistulous disease.