Cervicography involves the use of a specialized camera that is described as easy to use and not requiring experience in colposcopy. The photographs, referred to as cervigrams™, are static photographic images of the cervix similar to those seen during low-level magnification colposcopy. The images are sent to a central laboratory (National Testing Laboratories, the worldwide exclusive licensee of the product) for interpretation by colposcopists who have received specialized training in interpretation of cervigrams. Cervigrams are interpreted as negative, atypical, positive, or defective.
Cervicography has been investigated in three general settings:
- As an alternative to Pap smear screening as a primary screening technique for cervical cancer. This application has been investigated primarily in "resource poor" areas that do not have cytology expertise to interpret Pap smears.
- As an adjunct to routine Pap smear screening to improve the sensitivity of Pap smear screening for cervical cancer. For example, it is estimated that negative cytology reports are issued on 20% or more of all invasive cervical cancers.
- As a triage technique for colposcopy in patients found to have low-grade lesions on Pap smear specimens.
The management of low-grade lesions, i.e., atypical squamous cells of uncertain significance (ASCUS), has been a subject of investigation. For example, colposcopy is an option for further workup of ASCUS lesions, and yet at colposcopy only 20% of these patients actually have a high-grade lesion. Furthermore, many low-grade lesions that may prompt colposcopy will spontaneously regress. If cervicography can be used to identify which ASCUS cytology results are most likely to harbor higher grade lesions and thus need colposcopy and biopsy, unnecessary colposcopies in patients with innocuous cytologic abnormalities would decrease. Other triaging strategies include repeat Pap smears or evaluation for human papilloma virus (HPV) infection.
U.S. Food and Drug Administration (FDA) Approval or Marketing Clearance of Devices
In June 1982, the Cerviscope Optical System (Fotomedics) was cleared for marketing by the FDA through the 510(k) process. The FDA determined that this device was substantially equivalent to existing devices for viewing tissues of the vagina and cervix.
The procedure for conducting a speculoscopy involves several steps. First, the cervix is washed with 3–5% acetic acid. The examining room lights are then dimmed, and the cervix is visually examined using 5X magnifying loupes. The examination takes place using a disposable blue-white chemiluminescent light that is attached to the inner aspect of the upper speculum blade. Epithelial cells with increased keratinization and nuclear cytoplasmic ratios have an increased light reflection and appear white, in clear distinction to the dark blue of the normal epithelium. The presence of white lesions is considered a positive result; these areas may then be sampled for cytologic evaluation.
Speculoscopy must be distinguished from other methods of enhanced visual inspection of the cervix, including cervicography and colposcopy. Cervicography involves taking a picture of the cervix with a special macrolens strobe-flash camera after the cervix is swabbed with acetic acid. The photograph is then sent to a central laboratory for interpretation. Colposcopy involves the visual inspection of the cervix using a lighted microscope; unlike cervicography and speculoscopy, colposcopy has not been proposed as a primary screening method.
Two clinical roles of speculoscopy have been proposed, both as an adjunct to conventional cervical cancer screening and as a technique to select women with atypical cytological findings for further evaluation for colposcopy. For example, although cervical cancer screening is considered among the most successful cancer screening programs, it is still considered to be relatively insensitive; i.e., Papanicolaou (i.e. Pap) smear cytology is associated with false-negative results ranging from 15% to 55%. Speculoscopy is thought to potentially increase the sensitivity of cervical cancer screening by enhancing the visual inspection of the cervix.
Management of women with atypical Pap smears has evolved over the past several years, with a focus on various strategies to select those women with high-risk lesions who would benefit from further evaluation with colposcopy. Screening for human papillomavirus (HPV) is increasingly accepted as part of initial cervical cancer screening for women aged 30 years and older. In 2012 guidelines developed jointly by the American Cancer Society (ACS), American Society for Colposcopy and Cervical Pathology (ASCCP), and American Society for Clinical Pathology (ASCP), HPV and cytology “co-testing” every 5 years is the preferred screening strategy recommended for women aged 30-65 years; cytology alone every 3 years is included as an acceptable screening alternative. (19) Similarly, the United States Preventive Services Task Force (USPSTF) 2012 cervical cancer screening guideline recommends screening with a combination of cytology and HPV testing every 5 years for women for women aged 30 to 65 years who want to lengthen their screening interval. (20) Both 2012 guidelines recommend cytology only for women aged 21 to 29 years.
In 1995, speculoscopy using the Speculite® (Trylon Corp.; Monarch Beach, CA), a chemiluminescent light source, was cleared for marketing by the FDA through the 510(k) process. Later in 1995, the Pap Plus Speculoscopy (Trylon Corp.) was also cleared for marketing by the FDA and was later renamed PapSure®. It combined the Speculite device with a vaginal speculum, which is used for obtaining a Pap smear. In 2002, Watson Diagnostics, Inc. acquired the rights to PapSure and Speculite from Trylon Corporation, and they continue to market the combination device as PapSure. Speculite is intended for use only in conjunction with the Pap smear and is indicated for use in women currently recommended to undergo cervical screening with Pap smears.