From the Guidelines
Bleeding during or after thrombectomy is not always detectable on Computed Tomography Angiography (CTA) of the abdomen and pelvis. While CTA is a valuable imaging modality for detecting many types of bleeding, with a sensitivity ranging from 79% to 100% 1, it has limitations in sensitivity, particularly for slow, small-volume, or intermittent bleeding. Active extravasation of contrast material on CTA typically requires a bleeding rate of at least 0.3 mL/min to be visible 1. Post-thrombectomy bleeding may be subtle, especially if it occurs at a slow rate or has temporarily stopped at the time of imaging.
Some key points to consider when interpreting CTA results for bleeding detection include:
- The timing of the CTA is crucial; if performed too early or too late relative to the active bleeding episode, the hemorrhage might be missed.
- Other factors affecting detection include the location of bleeding (some areas are more difficult to visualize), patient factors such as obesity or motion artifacts, and technical parameters of the scan itself.
- A negative CTA is a good indicator that conservative management can be initiated, but management of unstable patients with negative CTA results remains challenging and should be approached on a case-by-case basis 1.
- For comprehensive assessment, clinicians should consider clinical symptoms, laboratory values (hemoglobin drops), and potentially other imaging modalities like conventional angiography, which offers higher sensitivity for detecting active bleeding, or follow-up imaging if clinical suspicion remains high despite initial negative findings.
In the context of thrombectomy, the ability of CTA to detect bleeding is influenced by the specifics of the procedure and the patient's condition, highlighting the need for a multifaceted approach to diagnosis and management.
From the Research
Bleeding Detection on CTA Abdomen Pelvis after Thrombectomy
- The detection of bleeding on Computed Tomography Angiography (CTA) of the abdomen and pelvis after thrombectomy is a critical aspect of patient care.
- Studies have shown that CTA can be effective in detecting bleeding and thrombi composition, but its accuracy may vary depending on several factors, such as the size and location of the thrombus, as well as the timing of the imaging procedure 2, 3.
- A study published in the Journal of Neurointerventional Surgery found that machine learning-based analysis of admission imaging can predict clot composition, which may help in selecting clot-specific devices and retrieval procedures for personalized thrombectomy strategies 2.
- However, another study published in the Journal of Neuroendovascular Therapy reported a case of hereditary hemorrhagic telangiectasia suspected due to anemia during anticoagulation therapy after thrombectomy, highlighting the importance of considering underlying conditions that may affect bleeding detection 4.
- Risk factors for intracranial hemorrhage after mechanical thrombectomy, such as infarct size, serum glucose levels, and thrombectomy maneuver count, have been identified in a study published in Neuroradiology 5.
- While these studies provide valuable insights into the detection of bleeding and thrombi composition, they may not directly address the question of whether bleeding on thrombectomy always shows on CTA abdomen pelvis.
- There is limited evidence to suggest that bleeding on thrombectomy is always detectable on CTA abdomen pelvis, and further research is needed to fully understand the relationship between thrombectomy, bleeding, and CTA imaging 6, 3.