Sampling methods
      Simple  cytobrush sampling is easier in the oral cavity in case the lesion is  localized (vesicular, exulcerated lesions). 
  Free  hand FNAB is useful in superficial lesions since they must be localized and  fixed using the sampler’s fingers. Superficial, subcutaneous or submucosus  lesions do not need US guidance;  most of the US  heads are too large for these lesions.
US  guidance is useful to avoid complications (bleeding, haematoma) and is absolutely necessary in deep lesions (tumors of nasopharynx, deep lobes of salivary glands) or large cystic lesions. Small  lesions localized next to the large vessels also need guidance.
CT  guidance is not real time: we may use the CT scan images for localization  before a free hand or US guided aspiration. 
      Staining methods 
      We may  use Giemsa (air dried smears), Papanicolaou  or H&E staining as well. Papanicolaou is  informative in squamous cell lesions, and so is H&E. Giemsa stained specimens can show metachromasia: extracellular matrix and the cytoplasm of  myoepithelial and connective tissue cells show metachromatic purple  staining. These cellular and extracellular components play a very important  role in the diagnostics of head and neck, especially salivary gland lesions. 
      Immunocytochemistry can be performed if needed (on cytospin preparared or liquid based material if possible).