The role of computed tomography angiography as initial imaging tool for acute hemorrhage in the head and neck.

OBJECTIVES: Acute hemorrhage in the head and neck (AHNH) is life-threatening due to asphyxiation and hemorrhagic shock. When conservative measures fail, some patients benefit from endovascular therapy (EVT). While CTA is routinely used to localize bleeding and plan EVT in gastrointestinal hemorrhage, the diagnostic value of CTA in AHNH and role of CTA in treatment-planning are uncertain. METHODS: We retrospectively reviewed neck CTAs from June 2015 to October 2018 indicated for AHNH. When performed, digital subtraction angiography (DSA) findings and EVT were documented. Extravasation or pseudoaneurysm on DSA was considered positive for bleed localization. RESULTS: Thirty CTA exams were performed for AHNH in 18 patients (mean age = 56.6, male% = 55.6%). Eleven out of 30 exams (36.7%) had immediate DSA follow-up within 24 h. Etiologies of hemorrhage included malignancy 11/18 (61.1%) and coagulopathy (4/18, 22.2%) among others. CTA reports identified definite or possible source of bleeding in 7/30 (23.3%) exams. Seven out of 7 (100%) patients with definite or possible source of bleeding on CTA underwent DSA and 4/23 (17.4%) patients underwent DSA despite negative CTA. With DSA as the gold standard, CTA had a sensitivity of 70% and a specificity of 100%. CONCLUSIONS: CTA has high specificity and reasonable sensitivity for detecting arterial source of bleeding in patients presenting with AHNH. Patients with negative CTA may avoid catheter angiography in most cases; however, false-negative CTA should not preclude angiography in high-risk patients.

Computed tomography window blending in maxillofacial imaging.

PURPOSE: The purpose of this study was to demonstrate the ability of a custom window blending algorithm to depict multicompartmental disease processes of the maxillofacial region in a single image, using routine computed tomography (CT) DICOM data. METHODS: Five cases were selected from case files demonstrating trauma, infection, and malignancy of the maxillofacial region on routine CT examinations. Images were processed with a modified Relative Attenuation-Dependent Image Overlay (RADIO) window-blending algorithm in Adobe Photoshop controlled by ExtendScript. RESULTS: The modified RADIO algorithm was able to demonstrate pertinent multicompartmental imaging findings in each of the examinations, allowing simultaneous visualization of clinically relevant bone and soft tissue findings in a single image, without needing to change window and level settings. CONCLUSION: A custom window blending algorithm can demonstrate a range of multicompartmental pathology in the maxillofacial region in a single image.