VIA procedure – Examination after application of 5% acetic acid – Detecting changes in the cervical epithelium after application of acetic acid
- While applying acetic acid, look for any new acetowhite patches appearing on the cervix. The columnar epithelium will be temporarily blanched; this is a normal finding.
- Identify the SCJ, which becomes prominent as a thin white line of demarcation between the pink smooth squamous epithelium and the red columnar epithelium.
- Note the location of the SCJ in relation to the external os (outside, partially inside, or completely inside the endocervical canal). Try to trace the SCJ through its entire 360° circumference. Sometimes the SCJ may not be fully visible in its entire 360° circumference on the ectocervix. In such cases, try to visualize it completely by using the following simple manipulations:
- Try opening the blades of the speculum slightly wider, taking care not to cause discomfort to the woman. If the SCJ is located close to the external os, it may become fully visible as a result of the mechanical stretching effect.
- Using a moist cotton swab, gently press on the cervical lips. Pushing the anterior lip up or pushing the posterior lip down may enable the SCJ to be completely visualized.
- Proceed to delineate the extent of the TZ by searching for nabothian cysts and crypt openings (occasionally visible to the naked eye) and the features of metaplasia (described later). Make sure to examine the entire TZ.
- If there is an acetowhite area (a white patch visible after application of acetic acid), assess it for:
- Rapidity of onset of acetowhitening, and time taken for acetowhitening to disappear
- Intensity of colour of the acetowhite epithelium (whether thin or dense)
- Margin: whether ill-defined or well-defined, whether smooth, feathery, or irregular, and whether flat or raised from the surface
- Location and number of acetowhite patches:
- Assess the location of the acetowhite area with respect to the TZ and attachment to the SCJ. Look for any extension of the lesion into the endocervical canal or onto the vaginal fornices.
- Note the number of acetowhite areas on the cervix and their location with respect to the TZ.
- Surface of the acetowhite area (whether smooth, irregular, or pitted)
- Size of acetowhite area, in terms of the number of quadrants of the cervix occupied and the percentage of the cervix involved.
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