VIA procedure Ė Examination after application of 5% acetic acid Ė Abnormal features Ė Location of acetowhite area
Acetowhite areas on the cervix may be located within the TZ and attached to the SCJ (or close to the external os, if the SCJ is not visible) or outside the TZ.
A dense acetowhite area that is located within the TZ and attached to the SCJ is more likely to be due to high-grade neoplasia. If the SCJ is not visible on the ectocervix, the location of the acetowhite area is assessed by its proximity to the external os. An acetowhite area within the TZ may extend into the endocervical canal, where the inner margin may or may not be visible.
An acetowhite area that is clearly outside the TZ (or away from the external os, if the SCJ is not visible) is VIA-negative irrespective of the density of the lesion.
In the presence of multiple acetowhite areas, the lesions that are located within the TZ and attached to the SCJ are considered as significant. Acetowhite areas that are detached from the SCJ are called satellite lesions and are usually due to infection with low-risk HPV types.
A large dense acetowhite area extending outside the TZ and occupying almost the entire cervix can be due to invasive cancer. Often, such a lesion bleeds on contact.