Visibility of Prevertebral Soft Tissues in the Neck Using Ultrasonography: A Feasibility Study

Objective: To aid emergent diagnosis of postoperative retropharyngeal hematoma in anterior cervical spine surgery patients, this study investigates ultrasonography's potential role by evaluating the visibility of retropharyngeal and prevertebral soft tissues in the neck using ultrasound and potential correlations with body habitus. Methods: The visibility of the anterior vertebral bodies and the prevertebral soft tissues in both sides of the neck was recorded and analyzed with 95% CI using the Wilson method. Body mass index, neck circumference, and neck length were measured. A point-biserial correlation was performed to compare body habitus with visibility of vertebrae and prevertebral tissues. Results: Longus colli muscle and C3 to C6 were successfully visualized in all 10 (100%) cases on both sides. C2 was only visible in 6 (60%) on both sides. C7 was visible in 9 (90%) on the right and 7 (70%) on the left. The esophagus was visible in 7 (70%) on the right and 10 (100%) on the left. There was a significant negative correlation with neck circumference and C2 visibility on the right side, r(8) = -0.76, P = 0.011. Conclusions: Ultrasonography was successful in visualizing prevertebral tissues, with a trend of obstructed visibility with wider and longer necks. Clinical Relevance: Ultrasonography has potential to aid early detection of postoperative retropharyngeal hematoma after cervical spine surgery. Level of Evidence: 4.