La imagen colposcópica es subjetiva y poco sensible
Chase DM, et al. Colposcopy to evaluate abnormal cervical cytology in 2008. Am J Obstet Gynecol. 2009 May;200(5):472-80.
El examen colposcópico es complejo y requiere habilidades.
Variaciones inter-observador e intra-observador: 52% concordancia inter-observevador.
65% concordancia intra-observervador.
Walker JL, et al. Predicting absolute risk of CIN3 during post-colposcopic follow-up: results from the ASCUS-LSIL Triage Study (ALTS). Am J Obstet Gynecol. 2006 Aug;195(2):341-8.
CH3-C(=O)-
H+
Acetic Acid in solution
Normal Cells
1. Cell walls of normal tissue will prevent transfer of hydrogen or acetate ions
C2H4O2 Dysplasia Cells in Lactic Acid
2. Intracellular space of dysplastic tissue contains lactic acid that causes recombination of acetic acid, which can then pass through cell walls
CH3-C(=O)- H+
Reflected White Light
3. Once inside the cell, the acetate ion reacts with cell nucleus changing its light reflective properties
In Vivo Molecular Imaging of Cervical Intra-Epithelial Neoplasia, C Balas, IEEE Vol 14, Jan 2008
• Colposcopia Digital computerizada
• Asistencia diagnóstica por software
• Creación de un mapa en tiempo real que
cuantifica el grado de las imágenes
• Localización de sitios de biopsia
• Base de datos de imágenes y video
• Standard examination process • High Resolution imaging • Acetic acid used as normal
2-3 mins
• Sequential images captured
• Dynamic Spectral analysis performed on each pixel (proprietary algorithms)
• Cellular response is measured • Characteristic curves relate to
tissue status at each pixel • DySISmap is generated
CIN1
CIN2
CIN3
Time
Dif
fuse
Ref
lect
ance
oDySISmap for improved diagnosis and sensitivity
oCIN3
oCIN2
oCIN1
oHPV
oInflammation
oLow-grade
oHigh-grade
oExtreme
oStrong
oModerate
oMild
DySISmap colour Aceto-whitening Level Cervical Neoplasia PAP Smear Grade
El mapeo DySIS es un código de colores sobre el cérvix que marca: Localización Márgenes Grado de las lesiones
Reduce la subjetividad Reduce la incertidumbre
Biopsy markers placed by clinician based on observed aceto-whitening
(#4 is a random control point).
DySISmap analysis of the same, showing the original biopsy markers – note the errors in the marker positions.
DySISmap assists in accurate biopsy location selection and
biopsy execution.
Clinical Trial Results
The results showed that DySIS has a higher sensitivity than conventional colposcopy
Soutter et al, Clinical Cancer Research 2009
308 women participated in a prospective, comparative, clinical trial conducted in three colposcopy clinics: two in London and one in Athens. The DySISmap was compared to colposcopic impression and referral cytology in identifying HG patients The sensitivity of conventional colposcopy to correctly identify women with high-grade neoplasia was 49%; the sensitivity of the DySISmap was 79%. DySIS detected an additional 22 (57 total) women with HG lesions.
49%
79%
Conventional colposcopy
DySISmap
sensitivity
275 women participated in a prospective, comparative, clinical trial conducted in three colposcopy clinics in the Netherlands. The sensitivity of conventional colposcopy to correctly assess women with high-grade neoplasia was 55%; the sensitivity of the DySISmap™ was 79%.
55%
79% 88%
Conventional colposcopy
DySISmap Conventional colposcopy plus DySISmap
The study showed that when the conventional colposcopic assessment of high-grade patients was combined with the DySISmap™ the sensitivity reached 88%.
Louwers, et al, Dynamic Spectral Imaging Colposcopy: Higher sensitivity for detection of premalignant cervical lesions, BJOG 2011
Clinical Trial Results
sensitivity
Zaal A, et al. BJOG. 2012 Feb 3. doi: 10.1111/j.1471-0528.2012.03280.x. [Epub ahead of print]
N=177
N=102
83,3 82,3 83,8
71,8
90,5 90,6 85,3
90,2 85,3
92,6 88,3
73,5
95,6 98,3
87,8
0
20
40
60
80
100
120
Precisión S E VPP VPN
Colpo DySIS Colo+DySIS
9 casos
111 casos. 102 en cérvix
77,8
100
66,7 60
100
55,6
66,7
50
40
75
0
20
40
60
80
100
120
Precisión S E VPP VPN
Colpo DySIS
Ninguna
Experiencia
Poca Mucha
P<0,001 P<0,001
50 preguntas
22 encuestas
Colposcopia DySIS Valor p
Aciertos
Media
Mediana
44%
22.1
21.0
52%
25.8
25.5
0.001
DySIS
0
5
10
15
20
25
30
35
40
45
50
Poco deacuerdo
2 3 4 Muy deacuerdo
Más Fácil
Orient Dx
Orient Bx
Más inform
Poca Exp
Mejor
0
20
40
60
80
100
120
Más fácil Orient Dx Orient Bx Más info Poca exp Mejor
Ninguna
Poca
Mucha
P=0,033
I. DySIS mejora algo la sensibilidad de la colposcopia
II. Útil en la orientación diagnóstica y elección de la biopsia
III. Más intuitivo y menos subjetivo que la colposcopia
IV. Bien valorado por los ginecólogos menos expertos