August 8, 2011

Colposcopy is the examination of the female genitals (cervix, vagina, or vulva) with an instrument called a colposcope. It is usually done to evaluate any lesions suspected of representing abnormal tissue growth or cancer. This may be an abnormal Pap smear or any lesion which does not resolve spontaneously in a reasonable amount of time as decided by the clinician. The colposcope is an instrument which permits magnification of lesions of the genital tract. A mild solution of acetic acid is applied to areas of the genital tract and abnormal areas turn white enhancing the quality of the colposcopic examination. All surface (epithelial) lesions become more distinct and structures including the cells on the wall of the cervix become more distinguishable using this method. After gross microscopic examination of the affected tissue for acetowhite changes and blood vessel patterns, tiny samples of tissue (biopsies) are removed and sent to pathology for histological (microscopic) evaluation. Colposcopy of the cervix can either be deemed satisfactory or unsatisfactory based upon the visualization of an area where the different types of cervical wall cells (squamous and columnar epithelium) of the cervix interface, called the transition zone (T zone) and all margins of any visible lesions. Sampling of the endometrium and endocervix may be necessary depending on the original abnormality noted upon cellular (cytological) examination of the Pap smear and the findings at colposcopy. If colposcopy is deemed unsatisfactory or if any high-grade lesion is suspected or diagnosed, a diagnostic excisional procedure (small tissue sample cutting) may be scheduled. This tissue is then examined for the characteristics of abnormal growth/cancer and for involvement of the margins. Techniques for excision include cervical conization (special type of tissue removal technique) using the laser or scalpel, loop electrosurgical excision (LEEP), or loop electrosurgical conization.

Usually biopsies are painless; however, a local anesthetic may be used during a diagnostic excisional procedure. Once performed, colposcopic evaluation is usually followed closely for at least 1-2 years.

During pregnancy, abnormal Pap smears are also evaluated by colposcopy and biopsies are necessary if the lesions appear high grade. Occasionally, a pregnant patient may need to undergo the surgical excision of a high-grade cervical lesion. The cervix is more vascular (increased blood supply) in pregnancy and there is an increased risk of bleeding. This risk is managed by performing the procedure in the hospital setting.

SEE ALSO: Pap test, Pregnancy

Category: C