Hyperspectral Diagnostic Imaging of the Cervix: Report on a New Investigational Device

Abstract

changes of about 25% in the height of the curve between scores of 1 and 5. Biopsies were classified as high grade (HG, CIN 2/3), low grade (LG, HPV/CIN 1), or nondysplastic (ND). Among women with abnormal Pap smears, only those who had biopsies with concordant interpretations by two independent pathologists were included in the descriptive analysis. All of the patients with normal Pap smears were included.Results. A total of 35 women were included in the analysis. Of 62 women with abnormal Pap smears who underwent fluorescence imaging and colposcopy, 31 met the inclusion criteria. Among these 31 women, Pap smears consisted of 6 atypical squamous cells of undetermined significance (ASCUS), 16 low-grade squamous intraepithelial lesions (LGSILs), and 9 high-grade squamous intraepithelial lesions (HGSILs). Of the 4 women with normal Pap smears, 1 had an abnormal colposcopy and a nondysplastic biopsy. Among all 35 women, 42 total biopsies were included, consisting of 11 HG, 25 LG, and 6 ND. Normal squamous tissue generated a score of 1, normal metaplastic tissue a score of 2 or 3, and normal columnar tissue of score of 5 in 35/35 (100%) women. Among the 11 HG lesions, 8 had a score of 4 and 2 had a score of 5. One case was uninterpretable due to a low signal-to-noise ratio. Among the 25 LG lesions, 15 had a score of 3, 6 had a score of 4 or 5, 2 had a score of 1, and 2 cases were uninterpretable.Conclusions. HG lesions generated spectra distinct from normal tissue in 8/10 (80%) evaluable cases, but LG lesions generated spectra indistinguishable from that of normal metaplastic tissue. Further modifications to this technique are Abstract Objective. To describe our experience with a noncontact in vivo fluorescence imaging device for the detection and localization of cervical intraepithelial neoplasia (CIN).Materials and Methods. Sixty-two women with abnormal Papanicolaou (Pap) smears, and 4 women with normal Pap smears, were recruited to undergo fluorescence imaging of the cervix during colposcopy. After topically applying dilute acetic acid, the surface of the cervix was scanned with 365 nm ultraviolet light for about 12 sec. Colposcopy and biopsies of visualized lesions were then performed. The fluorescence emission curves generated by normal cervical tissue and various states of cervical pathology were inspected and assigned relative scores of 1-5 based on the height and slope of the curves at peak fluorescence emissions. A score of 1 indicated a curve with high magnitude and distinct peak, and a score of 5 described a curve of low magnitude and rounded/flattened peak. Scores of 2-4 represented curves with incremental

Multimodal Hyperspectral Imaging for the Noninvasive Diagnosis of Cervical Neoplasia

“…Although other researchers have used fluorescence and reflectance mapping of the cervix to detect cervical neoplasia, those interrogations have been limited by the use of only a few emission wavelengths, a small and limited subject population, and in some cases, the interrogation of only a small portion of the cervix [14,15,17,18]. In our study, we sought to include a variety of women with varying disease and nondisease states, in order to better test the algorithms.…”

“…In this way, morphologic features of neoplasia, such as nuclear content, epithelial thickening, and neovascularization, may be detected as light is differentially absorbed, scattered, and reflected. Tissue fluorescence and reflected light measurements are analyzed using computer-based algorithms to determine whether the tissue is normal or abnormal; however, these systems have not been studied extensively [14,17,18]. The purpose of this study was to determine the feasibility of a Multimodal Hyperspectral Imaging (MHI) system to detect, localize, and diagnose cervical neoplasia in women.…”

Digitized Cervical Images: Problems, Solutions, and Potential Medical Impact

“…A computerized, algorithm-based, automated evaluation colposcopic device could help novice colposcopists identify and sample lesions determined to represent significant neoplasia. Because both use computer-based platforms, the automated image analysis tool easily could interface with fluorescent and reflective spectroscopy units to improve diagnostic accuracy [8][9][10]. Such an image analysis instrument also would help researchers analyze the NCI cervical image archive.…”

In Reply:

“…To the Editor: I have just finished reading "Hyperspectral Diagnostic Imaging of the Cervix: Report on a New Investigational Device," by Parker et al in the July 2000 issue of the Journal of Lower Genital Tract Disease [1]. The wheel keeps being reinvented.…”