Agrawal A, Utzinger U, Brookner C, Pitris C, Mitchell M F, Richards-Kortum R
SpectRx, Inc., Norcross, Georgia, USA.
Lasers Surg Med. 1999;25(3):237-49. doi: 10.1002/(sici)1096-9101(1999)25:3<237::aid-lsm8>3.0.co;2-f.
Fluorescence spectroscopy has been shown to provide information useful in the detection of cervical dysplasia. The goal of this study was to determine if substances found on the cervix such as acetic acid, mucus, and vaginal medications can influence the fluorescence in the spectral region useful for discriminating normal cervical tissue from abnormal tissue.
STUDY DESIGN/MATERIALS AND METHODS: Fluorescence spectra were collected at 337 nm excitation from the cervix in vivo both before and after application of acetic acid; the data were analyzed to identify the effects of the acetic acid on the spectra. Cervical mucus was acquired from patients referred for colposcopy and frozen until measurements were taken. Fluorescence excitation-emission matrices (EEMs) were measured for the mucus samples. Additionally, the transmission spectra of mucus were measured to determine if its absorption could influence the fluorescence signal measured from the tissue. EEMs were measured for samples of commonly prescribed vaginal medications. All EEMs were compared to those of cervical biopsies.
Acetic acid introduces changes in both the lineshape and intensity of the spectra. On average, the changes are more significant in spectra of abnormal tissue. Cervical mucus was found to have no significant absorption bands, but the measured fluorescence was approximately the same order of magnitude as that measured from the cervix in vitro. Most medications exhibited significant fluorescence in the spectral region of diagnostic interest for the cervix.
Acetic acid appears to increase the differences in fluorescence emission spectra of normal and pre-cancerous cervical tissues; thus, its use is beneficial. The presence of cervical mucus can possibly interfere with the collection of fluorescence spectra for tissue classification. Patients should not use vaginal preparations during the 48 hours prior to tissue fluorescence measurements.
荧光光谱已被证明能提供有助于检测宫颈发育异常的信息。本研究的目的是确定在宫颈上发现的物质，如醋酸、黏液和阴道用药，是否会影响在区分正常宫颈组织与异常组织时有用的光谱区域中的荧光。
研究设计/材料与方法：在体内应用醋酸前后，于337 nm激发波长下收集宫颈的荧光光谱；对数据进行分析以确定醋酸对光谱的影响。从接受阴道镜检查的患者处获取宫颈黏液并冷冻保存，直至进行测量。测量黏液样本的荧光激发-发射矩阵（EEMs）。此外，测量黏液的透射光谱，以确定其吸收是否会影响从组织测量的荧光信号。测量常用阴道用药样本的EEMs。将所有EEMs与宫颈活检样本的EEMs进行比较。
醋酸会使光谱的线形和强度发生变化。平均而言，这些变化在异常组织的光谱中更为显著。发现宫颈黏液没有明显的吸收带，但其测量的荧光与体外从宫颈测量的荧光大致处于相同数量级。大多数药物在宫颈诊断感兴趣的光谱区域表现出显著荧光。
醋酸似乎会增加正常和癌前宫颈组织荧光发射光谱的差异；因此，其使用是有益的。宫颈黏液的存在可能会干扰用于组织分类的荧光光谱采集。患者在组织荧光测量前48小时内不应使用阴道制剂。
