Low-dose CT: A safe and effective imaging modality in post-operative pelvic & acetabular fixation

Area of Science:

• Radiology
• Orthopedic Surgery
• Medical Imaging

Background:

• Conventional imaging for post-operative pelvic and acetabular fixation relies on 3-view radiographs (AP, inlet, outlet).
• These radiographs present challenges in achieving adequate views, leading to repeat imaging and increased radiation exposure.
• Interpretation difficulties can hinder assessment of fracture reduction and hardware placement, particularly around articular surfaces.

Purpose of the Study:

• To evaluate a novel imaging pathway for post-operative pelvic and acetabular fixation patients.
• To compare the efficacy, radiation dose, and logistical aspects of a low-dose CT and single radiograph protocol against the traditional 3-view radiograph approach.

Main Methods:

• A new low-dose pelvic CT protocol was developed, achieving high-quality 3D imaging with a 5-fold reduction in radiation dose compared to standard pelvic CT.
• Data from pelvic radiographs and CT scans between January 2021 and March 2022 were analyzed.
• Effective radiation dose and lifetime cancer risk were calculated using dose area product values.

Main Results:

• The average effective dose for traditional 3-view pelvic X-rays was 0.6 mSv, while the low-dose pelvic CT averaged 1.1 mSv.
• The traditional pathway involved a total effective dose of 4.2 mSv (1 in 11,000 cancer risk).
• The proposed pathway (low-dose CT plus single radiographs) resulted in a significantly lower effective dose of 2.3 mSv (1 in 20,000 cancer risk).

Conclusions:

• Low-dose CT scanning, combined with single-view radiographs, offers an effective and safe alternative for post-operative assessment of pelvic and acetabular fracture fixation.
• This new pathway reduces the overall radiation burden on patients.
• The proposed method also presents logistical advantages and yields higher quality images compared to the conventional 3-view radiograph approach.