Molecules such as proteins, nucleic acids, and carbohydrates have an affinity for water and are called hydrophilic (âwater-lovingâ). Lipids, however, are hydrophobic (âwater-fearingâ). Some lipids are amphipathicâpart of their structure is hydrophilic and another part, usually a larger section, is hydrophobic.
The high specificity at 10 and 11 mmindicates that lymph nodes of this size are almostalways metastatic in this level.A study of level II lymph nodes shows that for thewhole population a minimum diameter of 8 mm givesa relatively high sensitivity and specificity of 81% and80%, respectively.e found that a minimum axialdiameter of 7 mm for level II and 6 mm for the rest ofthe N0 neck represented the best compromise be-tween sensitivity and specificity. However, the size oflymph nodes was not an accurate predictor of metas-tasis in the N0 neck.
Lymph node size can also be a factor in deciding if a lymph node is normal or abnormal. Cervical lymph nodes have historically been considered abnormally enlarged if the longitudinal diameter of level I or level II nodes exceeded 15 mm, retropharyngeal nodes exceeded 8 mm, and other cervical nodes exceeded 10 mm.he level V lymph nodes are the nodes of the posterior cervical space corresponding to the SAC, lying posterior to the posterior margin of the SCM in a coronal plane (see Fig. 1 C). Level VA includes the upper SAC lymph nodes from the skull base to the inferior margin of the cricoid cartilage.