Predicting the Common Carotid Artery Bifurcation: A Comparative Assessment of Landmark-Based Methods.

introductionThe common carotid artery (CCA) bifurcation is a critical landmark in vascular surgery. There is a pressing need for a non-invasive, predictive method to accurately locate the CCA bifurcation. Using easily palpable anatomical landmarks, including the medial border of the clavicle (MBC), jugular notch (JN), and mastoid process (MP), we developed two new models for locating the CCA bifurcation and assessed their predictive reliability relative to a previously published method. MATERIALS AND

methodsFormalin-fixed human donors (n=30) were selected based on their suitability for comprehensive anterior neck dissections. Prior to dissection, straight-line measurements were obtained from the JN/MBC to the MP for each donor. Following neck dissections, secondary straight-line measurements were made from the JN/MBC to the MP and the CCA bifurcation. The location of the CCA bifurcation was predicted using three models. Model I involved multiplying the MBC-MP distance by 0.65/0.74 (right/left side) using a method described in a previously published study; Model II involved multiplying the MBC-MP distance by 0.59/0.57; and Model III involved multiplying the JN-MP distance by 0.585/0.58. The location of the CCA bifurcation as predicted by these models using pre- and post-dissection measurements was then compared with the actual location of the bifurcation to assess the external and internal validity, respectively, of each model.

resultsThe CCA bifurcation was, on average, located 4.23 mm higher on the right side than on the left side of the body when measuring from the MBC (p=0.026). However, after normalization for neck length, no significant difference was observed. Although bifurcation location based on Model I using pre-dissection measurements significantly deviated from actual measurements for both the left (p<0.0001) and right (p=0.002) sides, there were no significant differences between actual and predicted measurements for Model II or Model III. Similarly, using post-dissection measurements, Model I showed significant deviations from actual measurements on both the left (p < 0.0001) and right (p < 0.0001) sides, whereas there was no significant difference between actual and predicted measurements for Models II and III.

conclusionWe propose two new models for predicting the location of the CCA bifurcation using palpable landmarks: the MBC (Model II) and the JN (Model III). We noted that the latter method may prove to be more practical in the clinical setting. These non-invasive models could improve preoperative planning, surgical outcomes, and patient safety for carotid stenosis and stroke prevention. Future directions for this research include validating our models in other donor samples and clinical scenarios.