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2.
Int J Cancer ; 149(2): 431-441, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33811763

RESUMO

We conducted a prospective evaluation of the diagnostic performance of high-resolution microendoscopy (HRME) to detect cervical intraepithelial neoplasia (CIN) in women with abnormal screening tests. Study participants underwent colposcopy, HRME and cervical biopsy. The prospective diagnostic performance of HRME using an automated morphologic image analysis algorithm was compared to that of colposcopy using histopathologic detection of CIN as the gold standard. To assess the potential to further improve performance of HRME image analysis, we also conducted a retrospective analysis assessing performance of a multi-task convolutional neural network to segment and classify HRME images. One thousand four hundred eighty-six subjects completed the study; 435 (29%) subjects had CIN Grade 2 or more severe (CIN2+) diagnosis. HRME with morphologic image analysis for detection of CIN Grade 3 or more severe diagnoses (CIN3+) was similarly sensitive (95.6% vs 96.2%, P = .81) and specific (56.6% vs 58.7%, P = .18) as colposcopy. HRME with morphologic image analysis for detection of CIN2+ was slightly less sensitive (91.7% vs 95.6%, P < .01) and specific (59.7% vs 63.4%, P = .02) than colposcopy. Images from 870 subjects were used to train a multi-task convolutional neural network-based algorithm and images from the remaining 616 were used to validate its performance. There were no significant differences in the sensitivity and specificity of HRME with neural network analysis vs colposcopy for detection of CIN2+ or CIN3+. Using a neural network-based algorithm, HRME has comparable sensitivity and specificity to colposcopy for detection of CIN2+. HRME could provide a low-cost, point-of-care alternative to colposcopy and biopsy in the prevention of cervical cancer.


Assuntos
Histeroscopia/instrumentação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Displasia do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Brasil , Colposcopia , Sistemas Computacionais , Feminino , Humanos , Microtecnologia , Pessoa de Meia-Idade , Redes Neurais de Computação , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
3.
Int J Cancer ; 148(10): 2571-2578, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33368249

RESUMO

Cervical cancer remains a leading cause of cancer death for women in low- and middle-income countries. The goal of our study was to evaluate screening and triage strategies, including high-resolution microendoscopy (HRME), to detect cervical abnormalities concerning for precancer at the point of care. Women (n = 1824) were enrolled at the Instituto de Cáncer de El Salvador. All underwent screening by both human papillomavirus (HPV) testing using careHPV and visual inspection with acetic acid (VIA). Screen-positives, along with 10% of screen-negatives, were invited to return for a follow-up examination that included triage with VIA, colposcopy and HRME imaging. Biopsies were taken of any abnormalities identified. If no abnormalities were identified, then the worst scoring site by HRME was biopsied. The sensitivities of HPV testing and VIA to screen for cervical intraepithelial neoplasia Grade 2 or more severe diagnoses (CIN2+) were 82.1% and 75% (P = .77), while the specificities were 90.4% and 80.9% (P < .001), respectively. The sensitivities of VIA, colposcopy and HRME as triage tests for CIN2+ were 82.1%, 82.1% and 71.4%, respectively (P ≥ .38). HRME had a significantly higher specificity (66.7%) than VIA (51.9%) (P < .001) and colposcopy (53.3%) (P < .001). When evaluating different theoretical screening and triage strategies, screening with HPV testing followed by triage with HRME would result in more women receiving appropriate care (97%) compared to screening with VIA (75%) or HPV alone (90%). Our findings demonstrate that screening with HPV is superior to VIA, and that triage with HRME imaging increases the specificity of detecting CIN2+ at the point of care in a low-resource setting.

4.
Obstet Gynecol ; 133(3): 559-567, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30741811

RESUMO

BACKGROUND: Cervical cancer remains one of the leading causes of cancer for women in medically underserved areas. This is in part due to a lack of trained clinicians to provide the necessary diagnosis and treatment of precancerous lesions to prevent cervical cancer. Increasing medical provider knowledge and skills is important for the early detection and prevention of cervical precancer and cancer in medically underserved areas of the United States and globally. METHOD: LUCIA is a low-cost, universal cervical cancer instructional apparatus that can be used to teach and practice a variety of essential skills for cervical cancer screening, diagnosis, and treatment, including: visual inspection with acetic acid, Pap and human papillomavirus DNA specimen collection, colposcopy, endocervical curettage, cervical biopsy, cryotherapy, and loop electrosurgical excision procedure. EXPERIENCE: LUCIA was used to provide hands-on training in six courses held in Texas (n=3), El Salvador (n=1), and Mozambique, Africa (n=2). Standardized provider evaluations were administered at three of these courses and resulted in mean scores of 4.12/5 for usefulness, 4.46/5 for skill improvement, and 4.43/5 for ease of skill evaluation. CONCLUSION: LUCIA provides dynamic, real-time feedback that allows trainees to learn and practice important skills related to cervical cancer prevention while simulating a patient exam.


Assuntos
Países em Desenvolvimento , Detecção Precoce de Câncer , Educação Médica/métodos , Treinamento por Simulação/métodos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Biópsia , Colo do Útero/patologia , Competência Clínica , Colposcopia/educação , Detecção Precoce de Câncer/métodos , El Salvador , Desenho de Equipamento , Feminino , Humanos , Moçambique , Teste de Papanicolaou , Treinamento por Simulação/economia , Texas
5.
PLoS One ; 14(2): e0211045, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30726252

RESUMO

Nearly 90% of cervical cancer cases and deaths occur in low- and middle-income countries that lack comprehensive national HPV immunization and cervical cancer screening programs. In these settings, it is difficult to implement screening programs due to a lack of infrastructure and shortage of trained personnel. Screening programs based on visual inspection with acetic acid (VIA) have been successfully implemented in some low-resource settings. However, VIA has poor specificity and up to 90% of patients receiving treatment based on a positive VIA exam are over-treated. A number of studies have suggested that high-resolution cervical imaging to visualize nuclear morphology in vivo can improve specificity by better distinguishing precancerous and benign lesions. To enable high-resolution imaging in low-resource settings, we developed a portable, low-cost, high-resolution microendoscope that uses a mobile phone to detect and display images of cervical epithelium in vivo with subcellular resolution. The device was fabricated for less than $2,000 using commercially available optical components including filters, an LED and triplet lenses assembled in a 3D-printed opto-mechanical mount. We show that the mobile high-resolution microendoscope achieves similar resolution and signal-to-background ratio as previously reported high-resolution microendoscope systems using traditional cameras and computers to detect and display images. Finally, we demonstrate the ability of the mobile high-resolution microendoscope to image normal and precancerous squamous epithelium of the cervix in vivo in a gynecological referral clinic in Barretos, Brazil.


Assuntos
Telefone Celular , Colposcopia/métodos , Microscopia Intravital/métodos , Displasia do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/prevenção & controle , Brasil , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Colposcopia/economia , Colposcopia/instrumentação , Países em Desenvolvimento , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Células HeLa , Recursos em Saúde/provisão & distribuição , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Microscopia Intravital/economia , Microscopia Intravital/instrumentação , Programas de Rastreamento/economia , Programas de Rastreamento/instrumentação , Programas de Rastreamento/métodos , Aplicativos Móveis , Exame Físico/economia , Exame Físico/instrumentação , Exame Físico/métodos , Impressão Tridimensional , Sensibilidade e Especificidade , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia
6.
Photochem Photobiol ; 94(6): 1308-1313, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29981148

RESUMO

Proflavine is an acridine dye used with high-resolution microendoscopy for in vivo diagnostic evaluation of cervical epithelial cells. However, there are concerns that even short-term exposure of cervical tissue to dilute proflavine may increase cervical cancer risk. We performed a retrospective analysis of women referred for colposcopy to Barretos Cancer Hospital comparing the risk of cervical disease progression in those whose cervical tissue was (n = 232) or was not exposed (n = 160) to proflavine. Patients in both groups underwent treatment and follow-up based on histopathologic results and per the local standards of care. Progression of disease was evaluated by comparing histopathology from the initial visit to the worst subsequent histopathology result from all follow-up visits. Mean duration of follow-up was 18.7 and 20.1 months for the proflavine-exposed and controls groups, respectively. There were no significant differences in disease progression from normal/CIN1 to CIN2/3 or from any initial diagnosis to invasive cancer between the proflavine exposed and control groups overall. Risks of cervical dysplasia progression observed in this study are in agreement with those of the natural history of cervical cancer. Our results suggest that cervical exposure to dilute proflavine does not increase the risk of cervical precancer and cancer.


Assuntos
Colo do Útero/diagnóstico por imagem , Colposcopia/métodos , Meios de Contraste/administração & dosagem , Proflavina/administração & dosagem , Displasia do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Colo do Útero/metabolismo , Colo do Útero/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia
7.
Cancer Prev Res (Phila) ; 11(6): 359-370, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29618459

RESUMO

Cervical cancer is a leading cause of death in underserved areas of Brazil. This prospective randomized trial involved 200 women in southern/central Brazil with abnormal Papanicolaou tests. Participants were randomized by geographic cluster and referred for diagnostic evaluation either at a mobile van upon its scheduled visit to their local community, or at a central hospital. Participants in both arms underwent colposcopy, in vivo microscopy, and cervical biopsies. We compared rates of diagnostic follow-up completion between study arms, and also evaluated the diagnostic performance of in vivo microscopy compared with colposcopy. There was a 23% absolute and 37% relative increase in diagnostic follow-up completion rates for patients referred to the mobile van (102/117, 87%) compared with the central hospital (53/83, 64%; P = 0.0001; risk ratio = 1.37, 95% CI, 1.14-1.63). In 229 cervical sites in 144 patients, colposcopic examination identified sites diagnosed as cervical intraepithelial neoplasia grade 2 or more severe (CIN2+; 85 sites) with a sensitivity of 94% (95% CI, 87%-98%) and specificity of 50% (95% CI, 42%-58%). In vivo microscopy with real-time automated image analysis identified CIN2+ with a sensitivity of 92% (95% CI, 84%-97%) and specificity of 48% (95% CI, 40%-56%). Women referred to the mobile van were more likely to complete their diagnostic follow-up compared with those referred to a central hospital, without compromise in clinical care. In vivo microscopy in a mobile van provides automated diagnostic imaging with sensitivity and specificity similar to colposcopy. Cancer Prev Res; 11(6); 359-70. ©2018 AACR.


Assuntos
Colposcopia/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Microscopia/métodos , Unidades Móveis de Saúde/estatística & dados numéricos , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Seguimentos , Humanos , Técnicas In Vitro , Vida Independente , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , População Rural , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/epidemiologia
8.
Eur J Cancer Prev ; 26(1): 63-70, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26637074

RESUMO

Cervical cancer is the third leading cause of cancer-related death among women in low-to-middle income countries. Pap testing and pathological services are difficult to implement under these settings. Alternative techniques for the diagnosis of cervical precancer in these settings are needed to reduce the burden of the disease. The objective of this study was to evaluate the diagnostic accuracy of a low-cost, high-resolution microendoscope imaging system in identifying precancerous lesions of the cervix in vivo. A retrospective study of 59 patients undergoing colposcopy for an abnormal Pap test was performed at Hospital de Câncer de Barretos in Brazil. All patients underwent colposcopy as per standard of care, and acetowhite lesions were recorded. High-resolution microendoscopy (HRME) images were obtained from one colposcopically normal region and from all lesions observed on colposcopy. Biopsies of abnormal areas were obtained and reviewed by three independent, blinded pathologists and compared with HRME findings. The mean nuclear area and the median nuclear eccentricity were calculated from HRME images acquired from each site. A diagnostic algorithm to distinguish histopathologically diagnosed cervical intraepithelial neoplasias of grade 2 or more severe lesions (high grade) from less severe lesions (low grade) was developed using these parameters. A test of trend was used to analyze the relationship between HRME positivity and severity of histopathogical diagnosis. Fisher's exact test was used to analyze differences in HRME positivity between high-grade and low-grade lesions. Evaluable images were obtained from 108 of 143 discrete sites. Of these, 71 sites were colposcopically normal or low grade according to histopathology and 37 were diagnosed as high grade on the basis of histopathology. Using the mean nuclear area and the median nuclear eccentricity, HRME images from 59 colposcopically abnormal sites were classified as high grade or low grade with 92% sensitivity and 77% specificity compared with histopathological findings. Increasing HRME positivity showed a significant trend with increasing severity of diagnosis (Ptrend<0.001). We found a strong association (P<0.001) between HRME positivity and a histopathological diagnosis of cervical intraepithelial neoplasia of grade 2 or higher. HRME demonstrated an accurate in-situ diagnosis of high-grade dysplasia. In low-resource settings in which colposcopy and histopathology services are severely limited or unavailable, HRME may provide a low-cost, accurate method for diagnosis of cervical precancer without the need for biopsy, allowing for a single 'screen-and-treat' approach.


Assuntos
Colposcopia/economia , Recursos em Saúde/economia , Área Carente de Assistência Médica , Sistemas Automatizados de Assistência Junto ao Leito/economia , Displasia do Colo do Útero/economia , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Colposcopia/normas , Feminino , Tecnologia de Fibra Óptica/economia , Tecnologia de Fibra Óptica/normas , Recursos em Saúde/normas , Humanos , Histeroscopia/economia , Histeroscopia/normas , Microscopia de Fluorescência/economia , Microscopia de Fluorescência/normas , Pessoa de Meia-Idade , Projetos Piloto , Sistemas Automatizados de Assistência Junto ao Leito/normas , Estudos Retrospectivos , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Adulto Jovem
9.
Am J Trop Med Hyg ; 92(3): 583-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25510713

RESUMO

Giardia duodenalis is one of the most commonly identified parasites in stool samples. Although relatively easy to treat, giardiasis can be difficult to detect as it presents similar to other diarrheal diseases. Here, we present a recombinase polymerase amplification-based Giardia (RPAG) assay to detect the presence of Giardia in stool samples. The RPAG assay was characterized on the bench top using stool samples spiked with Giardia cysts where it showed a limit-of-detection nearly as low as the gold standard polymerase chain reaction assay. The RPAG assay was then tested in the highlands of Peru on 104 stool samples collected from the surrounding communities where it showed 73% sensitivity and 95% specificity against a polymerase chain reaction and microscopy composite gold standard. Further improvements in clinical sensitivity will be needed for the RPAG assay to have clinical relevance.


Assuntos
Fezes/parasitologia , Giardia lamblia/isolamento & purificação , Giardíase/diagnóstico , Reação em Cadeia da Polimerase/métodos , Recombinases/metabolismo , Giardíase/epidemiologia , Humanos , Peru/epidemiologia , Recombinases/química , Sensibilidade e Especificidade
10.
J Trop Pediatr ; 58(3): 178-83, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21914717

RESUMO

Our objective was to carry out a prospective, randomized, single-blind study to evaluate whether light emitting diode (LED) phototherapy using a low-cost set of lights is as effective as conventional phototherapy in treating hyperbilirubinemia in neonates. The study included 45 pre-term neonates requiring phototherapy as per American Academy of Pediatrics guidelines; participants were randomized to receive phototherapy using LED-based lights, conventional fluorescent blue lights or conventional halogen lights. There were no statistically significant differences in the average bilirubin levels at the onset, at the maximum and at the end of treatment, nor in the duration of phototherapy treatment and the rate of decrease in bilirubin levels in the neonates receiving conventional fluorescent blue light, conventional halogen light and LED phototherapy. (Differences were considered significant at p < 0.05). The average rate of decrease of bilirubin levels was 0.047 ± 0.037 mg dl(-1) h(-1), 0.055 ± 0.056 mg dl(-1) h(-1) and 0.057 ± 0.045 mg dl(-1) h(-1) in the groups receiving conventional fluorescent blue light, conventional halogen light and LED phototherapy, respectively. The average duration of phototherapy treatment in the three groups was 108.8 ± 85.9 h, 92.8 ± 38.1 h, 110.4 ± 42.6 h, respectively. In this pilot study, LED phototherapy using a simple, low-cost set of lights was as effective as conventional phototherapy in the treatment of neonatal hyperbilirubinemia. LED phototherapy lights that deliver 30-40 µW cm(-2 )nm(-1) can be assembled in small quantities for

Assuntos
Hiperbilirrubinemia Neonatal/terapia , Fototerapia/métodos , Bilirrubina/sangue , Custos e Análise de Custo , Feminino , Humanos , Hiperbilirrubinemia Neonatal/sangue , Recém-Nascido , Luz , Masculino , Fototerapia/economia , Fototerapia/instrumentação , Projetos Piloto , Estudos Prospectivos , Método Simples-Cego , Fatores de Tempo , Resultado do Tratamento
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