Oral Evaluation Diagnostic Aids Flashcards
(31 cards)
How has oral cancer detection been based on historically
Conventional Oral Examination
What is the term for precursor epithelial changes that almost all OSCC arise?
Oral epithelial Dysplasias (maturational disturbacnes of epithelial cells)
What are the sensitivity and specificity of Convnetional Oral Exam, and are auxillaries as accurate as dentsts
- 85% sensitivity
- 97% specificity
- Yes auxillaries are as good
What are the 3 limitation of a conventional oral exam?
1) Many mimics of cancerous and precancerous lesions
2) Can’t determine which precancerous lesion will progress to cancer
3) Precancerous lesions have been identified as normal mucosa
What is the difference between a Screening test and a Case-finding test?
- Screening- Used on people apparently free of disease in order to detect disease in early stages
- Case-finding- Test to analyze abnormal clinical findings or on symptomatic patient in order to establish a diagnosis
What aid is indicated to test common, small, harmless, appearing white or red tissue lesions that are seen weekly?
BrustTest
How should suspicious lesion be tested according to BrustTest
Scalpel biopsy
Where was the technique adopted from for BrustTest
Gynecologic practice
What are the 4 results provided by BrustTest
1) Negative- No precancerous cells
2) Atypical- Abnormal cells
3) Positive- Dysplastic cells
4) Incomplete Specimen- Insufficient cells
What are the results of the literature reviews for BrustTest
- Studies have design flaws (included suspicious lesion, inconsistent comparison to scalpel biopsy)
- False positives reported, and no diagnosis given
What screening test used Chemiluminescence
ViziLite Plus (2001,2005)
What is chemiluminescence?
Emission of light as a result of a chemical reaaction
What is the proposed mechanism of detection with ViziLite Plus
Altered reflective properties for abormal cells
- Normal- Dark
- Abnormal- Acetowhite
Literature review of ViziLite Plus
- Experimental design flaws
- Unable to discriminate benign from precancerous lesions, does not provide any benefit compared to oral exam
What are the 3 components of ViziLite Plus
1) 1% acetic acid- Remove debris and dehyrdrate cells
2) Disposable light stick
3) Toluidine blue (TBlue) dye- Mark lesion location with normal operatory light
What aid emits blue light (400-460 nm) and allows for direct visualization of oral cavity autofluorescence through a selective narrow band filter
VELscope
What does VELscope stand for?
- Visually Enhanced Lesion scope
What are fluorophores and what is the autofluorescent spectrum influenced by?
- Fluorophores- Molecules that emit energy in the form of fluorescence when excited by light
- Conc. of fluorophores, and absorption scattering properties of tissue
How should mucosal findings appear with VELscope
- Normal- Pale green, autofluorescence- negative
- Abnormal- Dark, positive finding
Review/limitations of VELscope
- Minimal data to support a true screening tool
- False positives (>90%) and false negatives
- Poor discrimination between malignant and benign
- Inf, vascularity, and melanin are distractors
What aid can possibly extend detection of oral cancer and precancer margins beyond conventional exam alone?
VELscope
What aid is based on multi-spectral fluorescence and reflectance spectroscopy and allows clinician to observe difference between normal and abnormal vasculature?
Identafi
What 3 color wavelengths are used with Identafi, and in what order?
1) White- conventional oral exam
2) Violet- Observation of tissue fluorescence, abnormal mucosa appears dark
3) Amber light for observing reflectance and vasculature
Literature review of Identafi
- Application of device not proven
