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1.
JID Innov ; 4(3): 100264, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38585192

RESUMEN

Intralesional therapies are used for recalcitrant warts, but no Food and Drug Administration-approved treatment exists nor is there consensus regarding the most efficacious therapy. Therefore, this systematic review aims to summarize efficacy and adverse events reported in 62 randomized controlled trials (RCTs) of intralesional therapies for cutaneous warts. The most studied intralesional therapies included measles, mumps, rubella (MMR) vaccine (n = 24 studies), purified protein derivative (PPD) (n = 19 studies), vitamin D3 (n = 15 studies), and Candida antigen (n = 14 studies). Most studies included adult and pediatric patients or adults alone, with only 4 studies on pediatric patients alone. MMR vaccine was the most studied treatment (n = 853 patients). MMR had a complete response rate of 27-90%. The next most common treatment, PPD, had a complete response rate of 45-87%. Other treatments included Candida antigen and vitamin D3, with complete response rates of 25-84% and 40-96%, respectively. The most frequent side effects were injection-site reactions and flu-like symptoms. This systematic review represents a useful summary of intralesional therapy RCTs for clinician reference. This study also highlights the lack of large multi-institutional RCTs, despite many patients being treated for this widespread problem.

2.
IEEE Trans Biomed Eng ; PP2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38060363

RESUMEN

: Local drug delivery aims to minimize systemic toxicity by preventing off-target effects; however, injection parameters influencing depot formation of injectable gels have yet to be thoroughly studied. We explored the effects of needle characteristics, injection depth, rate, volume, and polymer concentration on gel ethanol distribution in both tissue and phantoms. METHODS: The polymer ethyl cellulose (EC) was added to ethanol to form an injectable gel to ablate cervical precancer and cancer. Tissue mimicking phantoms composed of 1% agarose dissolved in deionized water were used to establish overall trends between various injection parameters and the resulting gel distribution. Additional experiments were performed in excised swine cervices with a CT-imageable injectate formulation, which enabled visualization of the distribution without tissue sectioning. RESULTS: Needle type and injection rate had minimal impact on gel distribution, while needle depths ≥13 mm yielded significantly larger distributions. Needle gauge and EC concentration impacted injection pressure with maximum gel distribution achieved when the pressure was 70-250 kPa. Injection volumes ≤3 mL of 6% ECethanol minimized fluid leakage away from the injection site. Results guided the development of a speculum-compatible handheld injector to deliver gel ethanol into the cervix. CONCLUSION: Needle depth, gauge, and polymer concentration are critical to consider when delivering injectable gels. SIGNIFICANCE: This study addressed key questions related to the impact of injection-based parameters on gel distribution at a scale relevant to human applications including: 1) how best to deliver EC-ethanol into the cervix and 2) general insights about injection protocols relevant to the delivery of injectable gels in tissue.

3.
Bioengineering (Basel) ; 10(11)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-38002370

RESUMEN

Current therapies for treating cervical dysplasia are often inaccessible in low and middle-income countries (LMICs), highlighting the need for novel low-cost therapies that can be delivered at the point of care. Ethanol ablation is a low-cost therapy designed to treat locoregional cancers, which we augmented into an ethyl cellulose (EC)-ethanol gel formulation to enhance its efficacy. Here, we evaluated whether EC-ethanol ablation is able to safely achieve an ablation zone comparable to thermocoagulation, a commonly used therapy for cervical dysplasia. The study was performed in 20 female Yorkshire pigs treated with either a single 500 µL injection of EC-ethanol into the 12 o'clock position of the cervix or a single application of thermocoagulation at 100 °C for 20 s. The average temperature, heart rate, respiratory rate, and blood oxygen remained within normal ranges throughout the EC-ethanol procedure and were similar to the thermocoagulation group. No major side effects were observed. The reproductive tracts were excised after 24 h to examine ablation zones. Comparable depths of necrosis were seen for EC-ethanol (18.6 ± 1.6 mm) and thermocoagulation (19.7 ± 4.1 mm). The volumes of necrosis induced by a single injection of EC-ethanol (626.2 ± 122.8 µL) were comparable to the necrotic volumes induced by thermocoagulation in the top half of the cervices (664.6 ± 168.5 µL). This suggests that two EC-ethanol injections could be performed (e.g., at the 12 and 6 o'clock positions) to achieve comparable total necrotic volumes to thermocoagulation and safely and effectively treat women with cervical dysplasia in LMICs. This is the first study to systematically evaluate EC-ethanol ablation in a large animal model and compare its safety and efficacy to thermocoagulation, a commonly used ablative therapy for cervical dysplasia.

5.
Surg Endosc ; 37(8): 5943-5955, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37074419

RESUMEN

BACKGROUND: Many surgeons in low- and middle-income countries have described performing surgery using gasless (lift) laparoscopy due to inaccessibility of carbon dioxide and reliable electricity, but the safety and feasibility of the technique has not been well documented. We describe preclinical testing of the in vivo safety and utility of KeyLoop, a laparoscopic retractor system to enable gasless laparoscopy. METHODS: Experienced laparoscopic surgeons completed a series of four laparoscopic tasks in a porcine model: laparoscopic exposure, small bowel resection, intracorporeal suturing with knot tying, and cholecystectomy. For each participating surgeon, the four tasks were completed in a practice animal using KeyLoop. Surgeons then completed these tasks using standard-of-care (SOC) gas laparoscopy and KeyLoop in block randomized order to minimize learning curve effect. Vital signs, task completion time, blood loss and surgical complications were compared between SOC and KeyLoop using paired nonparametric tests. Surgeons completed a survey on use of KeyLoop compared to gas laparoscopy. Abdominal wall tissue was evaluated for injury by a blinded pathologist. RESULTS: Five surgeons performed 60 tasks in 15 pigs. There were no significant differences in times to complete the tasks between KeyLoop and SOC. For all tasks, there was a learning curve with task completion times related to learning the porcine model. There were no significant differences in blood loss, vital signs or surgical complications between KeyLoop and SOC. Eleven surgeons from the United States and Singapore felt that KeyLoop could be used to safely perform several common surgical procedures. No abdominal wall tissue injury was observed for either KeyLoop or SOC. CONCLUSIONS: Procedure times, blood loss, abdominal wall tissue injury and surgical complications were similar between KeyLoop and SOC gas laparoscopy for basic surgical procedures. This data supports KeyLoop as a useful tool to increase access to laparoscopy in low- and middle-income countries.


Asunto(s)
Pared Abdominal , Laparoscopía , Porcinos , Animales , Estudios de Factibilidad , Laparoscopía/métodos , Dióxido de Carbono , Colecistectomía
6.
Value Health Reg Issues ; 33: 83-90, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36327768

RESUMEN

OBJECTIVES: Medical devices that suit the needs and challenges of low- and middle-income countries are desperately needed. To provide sustainable access to such devices, business approaches must be developed to meet the demands of individual economic, healthcare, and innovation ecosystems. Currently, there is a gap in the literature regarding business models for medical devices in low- and middle-income countries. METHODS: A multimodal approach using literature review and key informant interviews was performed to determine critical components of business models for medical device organizations operating in LMICs, specifically focusing on models in emerging markets. RESULTS: The search resulted in 4,674 articles, of which 31 were determined to be relevant and were reviewed. Additional sources included 1 government website, 5 nongovernmental organization websites, 2 private enterprises, and 6 publicly available, non-peer reviewed websites and 1 video. From these sources, four major criteria were found to be necessary for successful development of medical device business models in emerging markets: value proposition, partnerships, strategic pricing, and funding models. CONCLUSIONS: Innovators must custom tailor their business model when implementing these elements to the regulatory, cultural, and economic landscapes of each setting. This will improve access to safer, affordable medical care and successfully bring innovative technologies to emerging markets.


Asunto(s)
Comercio , Ecosistema , Humanos , Atención a la Salud , Países en Desarrollo , Sector Privado
8.
Surg Innov ; 29(1): 88-97, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34242531

RESUMEN

Background. Despite favorable outcomes of laparoscopic surgery in high-income countries, its implementation in low- and middle-income countries (LMICs) is challenging given a shortage of consumable supplies, high cost, and risk of power outages. To overcome these barriers, we designed a mechanical retractor that provides vertical tension on the anterior abdominal wall. Methods. The retractor design is anatomically and mathematically optimized to provide exposure similar to traditional gas-based insufflation methods. Anatomical data from computed tomography scans were used to define retractor size. The retractor is constructed of biocompatible stainless steel rods and paired with a table-mounted lifting system to provide 5 degrees of freedom. Structural integrity was assessed through finite element analysis (FEA) and load testing. Functional testing was performed in a laparotomy model. Results. A user guide based on patient height and weight was created to customize retractor size, and 4 retractor sizes were constructed. FEA data using a 13.6 kg mass (15 mm Hg pneumoperitoneum) show a maximum of 30 mm displacement with no permanent deformation. Physical load testing with applied weight from 0 to 13.6 kg shows a maximum of 60 mm displacement, again without permanent deformation. Retraction achieved a 57% larger field of view compared to an unretracted state in a laparotomy model. Conclusions. The KeyLoop retractor maintains structural integrity, is easily sterilized, and can be readily manufactured, making it a viable alternative to traditional insufflation methods. For surgeons and patients in LMICs, the KeyLoop provides a means to increase access to laparoscopic surgery.


Asunto(s)
Pared Abdominal , Insuflación , Laparoscopía , Cirujanos , Pared Abdominal/cirugía , Humanos , Laparoscopía/métodos , Laparotomía
9.
Nano Life ; 11(2)2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34484435

RESUMEN

Photodynamic therapy (PDT) is a two-step procedure that involves the administration of special drugs, commonly called photosensitizers, followed by the application of certain wavelengths of light. The light activates these photosensitizers to produce reactive molecular species that induce cell death in tissues. There are numerous factors to consider when selecting the appropriate photosensitizer administration route, such as which part of the body is being targeted, the pharmacokinetics of photosensitizers, and the formulation of photosensitizers. While intravenous, topical, and oral administration of photosensitizers are widely used in preclinical and clinical applications of PDT, other administration routes, such as intraperitoneal, intra-arterial, and intratumoral injections, are gaining traction for their potential in treating advanced diseases and reducing off-target toxicities. With recent advances in targeted nanotechnology, biomaterials, and light delivery systems, the exciting possibilities of targeted photosensitizer delivery can be fully realized for preclinical and clinical applications. Further, in light of the growing burden of cancer mortality in low and middle-income countries and development of low-cost light sources and photosensitizers, PDT could be used to treat cancer patients in low-income settings. This short article introduces aspects of interfaces of intratumoral photosensitizer injections and nano-biomaterials for PDT applications in both high-income and low-income settings but does not present a comprehensive review due to space limitations.

10.
Sci Rep ; 11(1): 16869, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34413378

RESUMEN

In low-income countries, up to 80% of women diagnosed with cervical dysplasia do not return for follow-up care, primarily due to treatment being inaccessible. Here, we describe development of a low-cost, portable treatment suitable for such settings. It is based on injection of ethyl cellulose (EC)-ethanol to ablate the transformation zone around the os, the site most impacted by dysplasia. EC is a polymer that sequesters the ethanol within a prescribed volume when injected into tissue, and this is modulated by the injected volume and delivery parameters (needle gauge, bevel orientation, insertion rate, depth, and infusion rate). Salient injection-based delivery parameters were varied in excised swine cervices. The resulting injection distribution volume was imaged with a wide-field fluorescence imaging device or computed tomography. A 27G needle and insertion rate of 10 mm/s achieved the desired insertion depth in tissue. Orienting the needle bevel towards the outer edge of the cervix and keeping infusion volumes ≤ 500 µL minimized leakage into off-target tissue. These results guided development of a custom hand-held injector, which was used to locate and ablate the upper quadrant of a swine cervix in vivo with no adverse events or changes in host temperature or heart rate. After 24 h, a distinct region of necrosis was detected that covered a majority (> 75%) of the upper quadrant of the cervix, indicating four injections could effectively cover the full cervix. The work here informs follow up large animal in vivo studies, e.g. in swine, to further assess safety and efficacy of EC-ethanol ablation in the cervix.


Asunto(s)
Ablación por Catéter , Celulosa/análogos & derivados , Etanol/administración & dosificación , Displasia del Cuello del Útero/cirugía , Animales , Celulosa/química , Femenino , Fluoresceína/química , Inyecciones , Modelos Animales , Agujas , Reproducibilidad de los Resultados , Porcinos , Tomografía Computarizada por Rayos X , Displasia del Cuello del Útero/diagnóstico por imagen
11.
Glob Health Sci Pract ; 9(1): 136-148, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33764886

RESUMEN

Effective regulatory frameworks, harmonized to international standards, are critical to expanding access to quality medical devices in low- and middle-income countries. This review provides a summary of the state of medical device regulation in the 14 member countries of the College of Surgeons of East, Central, and Southern Africa (COSECSA) and South Africa. Countries were categorized according to level of regulatory establishment, which was found to be positively correlated to gross domestic product (GDP; rs=0.90) and years of freedom from colonization (rs=0.60), and less positively correlated to GDP per capita (rs=0.40). Although most countries mandate medical device regulation in national legislation, few employ all the guidelines set forth by the World Health Organization. A streamlined regulatory process across African nations would simplify this process for innovators seeking to bring medical devices to the African market, thereby increasing patient access to safe medical devices.


Asunto(s)
Legislación de Dispositivos Médicos , Cirujanos , África Austral , Humanos , Renta , Sudáfrica
12.
Ann Biomed Eng ; 49(7): 1657-1669, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33686617

RESUMEN

Laparoscopic surgery is the standard of care in high-income countries for many procedures in the chest and abdomen. It avoids large incisions by using a tiny camera and fine instruments manipulated through keyhole incisions, but it is generally unavailable in low- and middle-income countries (LMICs) due to the high cost of installment, lack of qualified maintenance personnel, unreliable electricity, and shortage of consumable items. Patients in LMICs would benefit from laparoscopic surgery, as advantages include decreased pain, improved recovery time, fewer wound infections, and shorter hospital stays. To address this need, we developed an accessible laparoscopic system, called the ReadyView laparoscope for use in LMICs. The device includes an integrated camera and LED light source that can be displayed on any monitor. The ReadyView laparoscope was evaluated with standard optical imaging targets to determine its performance against a state-of-the-art commercial laparoscope. The ReadyView laparoscope has a comparable resolving power, lens distortion, field of view, depth of field, and color reproduction accuracy to a commercially available endoscope, particularly at shorter, commonly-used working distances (3-5 cm). Additionally, the ReadyView has a cooler temperature profile, decreasing the risk for tissue injury and operating room fires. The ReadyView features a waterproof design, enabling sterilization by submersion, as commonly performed in LMICs. A custom desktop software was developed to view the video on a laptop computer with a frame rate greater than 30 frames per second and to white balance the image, which is critical for clinical use. The ReadyView laparoscope is capable of providing the image quality and overall performance needed for laparoscopic surgery. This portable low-cost system is well suited to increase access to laparoscopic surgery in LMICs.


Asunto(s)
Diseño de Equipo , Laparoscopios , Laparoscopía , Humanos
13.
PLoS One ; 16(1): e0234535, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33507942

RESUMEN

Focal tumor ablation with ethanol could provide benefits in low-resource settings because of its low overall cost, minimal imaging technology requirements, and acceptable clinical outcomes. Unfortunately, ethanol ablation is not commonly utilized because of a lack of predictability of the ablation zone, caused by inefficient retention of ethanol at the injection site. To create a predictable zone of ablation, we have developed a polymer-assisted ablation method using ethyl cellulose (EC) mixed with ethanol. EC is ethanol-soluble and water-insoluble, allowing for EC-ethanol to be injected as a liquid and precipitate into a solid, occluding the leakage of ethanol upon contact with tissue. The aims of this study were to compare the 1) safety, 2) release kinetics, 3) spatial distribution, 4) necrotic volume, and 5) overall survival of EC-ethanol to conventional ethanol ablation in a murine breast tumor model. Non-target tissue damage was monitored through localized adverse events recording, ethanol release kinetics with Raman spectroscopy, injectate distribution with in vivo imaging, target-tissue necrosis with NADH-diaphorase staining, and overall survival by proxy of tumor growth. EC-ethanol exhibited decreased localized adverse events, a slowing of the release rate of ethanol, more compact injection zones, 5-fold increase in target-tissue necrosis, and longer overall survival rates compared to the same volume of pure ethanol. A single 150 µL dose of 6% EC-ethanol achieved a similar survival probability rates to six daily 50 µL doses of pure ethanol used to simulate a slow-release of ethanol over 6 days. Taken together, these results demonstrate that EC-ethanol is safer and more effective than ethanol alone for ablating tumors.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Depresores del Sistema Nervioso Central/administración & dosificación , Etanol/administración & dosificación , Animales , Apoptosis , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Surg Endosc ; 35(12): 6539-6548, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33201314

RESUMEN

BACKGROUND: Laparoscopic surgery has become standard of care in high-income countries but is rarely accessible in low- and middle-income countries (LMICs). This study assessed experience with laparoscopy and attitudes toward a low-cost laparoscopic system among surgeons in sub-Saharan Africa. METHODS: A survey assessing current laparoscopic practice and feedback on a low-cost laparoscopic system was administered to attendees of the College of Surgeons of East, Central, and Southern Africa (COSECSA) Scientific Conference between December 4 and December 6, 2019 in Kampala, Uganda. RESULTS: Fifty-six surgeons from 14 countries participated. A majority were male (n = 46, 82%) general surgeons (n = 37, 66%) from tertiary/teaching hospitals (n = 36, 64%). For those with training in laparoscopy (n = 33, 59%), 22 (67%) reported less than 1 year of training and over half (n = 17, 52%) reported 1 month or less. Overall, a minority (n = 21, 38%) used laparoscopy in current practice, with 57% (n = 12) of those performing laparoscopy less than once per week. The most common laparoscopic surgeries performed were cholecystectomy (n = 15), diagnostic laparoscopy (n = 14), and appendectomy (n = 12). Few surgeons were performing more complex cases (n = 5). Barriers to laparoscopy included poor access to training equipment (n = 34, 61%), mentors (n = 33, 59%), laparoscopic equipment (n = 31, 55%), equipment maintenance (n = 25, 45%), access to consumable supplies (n = 21, 38%), and cost (n = 31, 55%). Fifty-two participants (93%) were interested in increasing their use of laparoscopy; the majority felt that a low-cost laparoscope (n = 52, 93%) and lift retractor for gasless laparoscopy (n = 46, 82%) would serve an unmet need in their practice. CONCLUSIONS: While the use of laparoscopy is currently limited in COSECSA countries, there is a significant interest among surgeons to increase implementation. A low-cost, durable laparoscopic system was viewed as a potential solution to the current barriers and could improve implementation in LMICs.


Asunto(s)
Laparoscopía , Cirujanos , África Austral , Actitud , Femenino , Humanos , Masculino , Uganda
15.
IEEE Trans Biomed Eng ; 67(8): 2337-2348, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31841399

RESUMEN

OBJECTIVE: Ethanol ablation, the injection of ethanol to induce necrosis, was originally used to treat hepatocellular carcinoma, with survival rates comparable to surgery. However, efficacy is limited due to leakage into surrounding tissue. To reduce leakage, we previously reported incorporating ethyl cellulose (EC) with ethanol as this mixture forms a gel when injected into tissue. To further develop EC-ethanol injection as an ablative therapy, the present study evaluates the extent to which salient injection parameters govern the injected fluid distribution. METHODS: Utilizing ex vivo swine liver, injection parameters (infusion rate, EC%, infusion volume) were examined with fluorescein added to each solution. After injection, tissue samples were frozen, sectioned, and imaged. RESULTS: While leakage was higher for ethanol and 3%EC-ethanol at a rate of 10 mL/hr compared to 1 mL/hr, leakage remained low for 6%EC-ethanol regardless of infusion rate. The impact of infusion volume and pressure were also investigated first in tissue-mimicking surrogates and then in tissue. Results indicated that there is a critical infusion pressure beyond which crack formation occurs leading to fluid leakage. At a rate of 10 mL/hr, a volume of 50 µL remained below the critical pressure. CONCLUSIONS: Although increasing the infusion rate increases stress on the tissue and the risk of crack formation, injections of 6%EC-ethanol were localized regardless of infusion rate. To further limit leakage, multiple low-volume infusions may be employed. SIGNIFICANCE: These results, and the experimental framework developed to obtain them, can inform optimizing EC-ethanol to treat a range of medical conditions.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Neoplasias Hepáticas , Animales , Celulosa/análogos & derivados , Etanol , Neoplasias Hepáticas/tratamiento farmacológico , Porcinos
16.
IEEE Trans Biomed Eng ; 66(8): 2306-2318, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30575526

RESUMEN

GOAL: In this paper, we propose methods for (1) automatic feature extraction and classification for acetic acid and Lugol's iodine cervigrams and (2) methods for combining features/diagnosis of different contrasts in cervigrams for improved performance. METHODS: We developed algorithms to pre-process pathology-labeled cervigrams and extract simple but powerful color and textural-based features. The features were used to train a support vector machine model to classify cervigrams based on corresponding pathology for visual inspection with acetic acid, visual inspection with Lugol's iodine, and a combination of the two contrasts. RESULTS: The proposed framework achieved a sensitivity, specificity, and accuracy of 81.3%, 78.6%, and 80.0%, respectively, when used to distinguish cervical intraepithelial neoplasia (CIN+) relative to normal and benign tissues. This is superior to the average values achieved by three expert physicians on the same data set for discriminating normal/benign cases from CIN+ (77% sensitivity, 51% specificity, and 63% accuracy). CONCLUSION: The results suggest that utilizing simple color- and textural-based features from visual inspection with acetic acid and visual inspection with Lugol's iodine images may provide unbiased automation of cervigrams. SIGNIFICANCE: This would enable automated, expert-level diagnosis of cervical pre-cancer at the point of care.


Asunto(s)
Algoritmos , Colposcopios , Interpretación de Imagen Asistida por Computador/métodos , Lesiones Precancerosas/diagnóstico por imagen , Neoplasias del Cuello Uterino/diagnóstico por imagen , Cuello del Útero/diagnóstico por imagen , Detección Precoz del Cáncer/instrumentación , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/instrumentación , Aprendizaje Automático , Sistemas de Atención de Punto
17.
PLoS One ; 13(2): e0192530, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29425225

RESUMEN

INTRODUCTION: We have previously developed a portable Pocket Colposcope for cervical cancer screening in resource-limited settings. In this manuscript we report two different strategies (cross-polarization and an integrated reflector) to improve image contrast levels achieved with the Pocket Colposcope and evaluate the merits of each strategy compared to a standard-of-care digital colposcope. The desired outcomes included reduced specular reflection (glare), increased illumination beam pattern uniformity, and reduced electrical power budget. In addition, anti-fogging and waterproofing features were incorporated to prevent the Pocket Colposcope from fogging in the vaginal canal and to enable rapid disinfection by submersion in chemical agents. METHODS: Cross-polarization (Generation 3 Pocket Colposcope) and a new reflector design (Generation 4 Pocket Colposcope) were used to reduce glare and improve contrast. The reflector design (including the angle and height of the reflector sidewalls) was optimized through ray-tracing simulations. Both systems were characterized with a series of bench tests to assess specular reflection, beam pattern uniformity, and image contrast. A pilot clinical study was conducted to compare the Generation 3 and 4 Pocket Colposcopes to a standard-of-care colposcope (Leisegang Optik 2). Specifically, paired images of cervices were collected from the standard-of-care colposcope and either the Generation 3 (n = 24 patients) or the Generation 4 (n = 32 patients) Pocket Colposcopes. The paired images were blinded by device, randomized, and sent to an expert physician who provided a diagnosis for each image. Corresponding pathology was obtained for all image pairs. The primary outcome measures were the level of agreement (%) and κ (kappa) statistic between the standard-of-care colposcope and each Pocket Colposcope (Generation 3 and Generation 4). RESULTS: Both generations of Pocket Colposcope had significantly higher image contrast when compared to the standard-of-care colposcope. The addition of anti-fog and waterproofing features to the Generation 3 and 4 Pocket Colposcope did not impact image quality based on qualitative and quantitative metrics. The level of agreement between the Generation 3 Pocket Colposcope and the standard-of-care colposcope was 75.0% (kappa = 0.4000, p = 0.0028, n = 24). This closely matched the level of agreement between the Generation 4 Pocket Colposcope and the standard-of-care colposcope which was also 75.0% (kappa = 0.4941, p = 0.0024, n = 32). CONCLUSION: Our results indicate that the Generation 3 and 4 Pocket Colposcopes perform comparably to the standard-of-care colposcope, with the added benefit of being low-cost and waterproof, which is ideal for use in resource-limited settings. Additionally, the reflector significantly reduces the electrical requirements of the Generation 4 Pocket Colposcope enhancing portability without altering performance compared to the Generation 3 system.


Asunto(s)
Colposcopía/instrumentación , Neoplasias del Cuello Uterino/diagnóstico , Femenino , Humanos
18.
Sci Rep ; 7(1): 8750, 2017 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-28821832

RESUMEN

While surgery is at the foundation of cancer treatment, its access is limited in low-income countries. Here, we describe development of a low-cost alternative therapy based on intratumoral ethanol injection suitable for resource-limited settings. Although ethanol-based tumor ablation is successful in treating hepatocellular carcinomas, the necessity for multiple treatments, injection of large fluid volumes, and decreased efficacy in treatment of non-capsulated tumors limit its applicability. To address these limitations, we investigated an enhanced ethanol ablation strategy to retain ethanol within the tumor through the addition of ethyl cellulose. This increases the viscosity of injected ethanol and forms an ethanol-based gel-phase upon exposure to the aqueous tumor environment. This technique was first optimized to maximize distribution volume, using tissue-simulating phantoms. Then, chemically-induced epithelial tumors in the hamster cheek pouch were treated. As controls, pure ethanol injections of either four times or one-fourth the tumor volume induced complete regression of 33% and 0% of tumors, respectively. In contrast, ethyl cellulose-ethanol injections of one-fourth the tumor volume induced complete regression in 100% of tumors. These results contribute to proof-of-concept for enhanced ethanol ablation as a novel and effective alternative to surgery for tumor treatment, with relevance to resource-limited settings.


Asunto(s)
Ablación por Catéter/métodos , Etanol/administración & dosificación , Neoplasias/terapia , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Celulosa/análogos & derivados , Celulosa/química , Cricetinae , Modelos Animales de Enfermedad , Etanol/química , Femenino , Humanos , Inyecciones Intralesiones , Neoplasias/diagnóstico , Fantasmas de Imagen , Resultado del Tratamiento , Carga Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Low Genit Tract Dis ; 21(2): 112-119, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28263237

RESUMEN

OBJECTIVE: Barriers to cervical cancer screening in low-resource settings include lack of accessible, high-quality services, high cost, and the need for multiple visits. To address these challenges, we developed a low-cost, intravaginal, optical cervical imaging device, the point-of-care tampon (POCkeT) colposcope and evaluated whether its performance is comparable with a standard-of-care colposcope. MATERIALS AND METHODS: There were 2 protocols, which included 44 and 18 patients. For the first protocol, white-light cervical images were collected in vivo, blinded by device, and sent electronically to 8 physicians from high-, middle-, and low-income countries. For the second protocol, green-light images were also collected and sent electronically to the highest performing physician from the first protocol who has experience in both a high- and low-income country. For each image, physicians completed a survey assessing cervix characteristics and severity of precancerous lesions. Corresponding pathology was obtained for all image pairs. RESULTS: For the first protocol, average percent agreement between devices was 70% across all physicians. The POCkeT and standard-of-care colposcope images had 37% and 51% agreement with pathology for high-grade squamous intraepithelial lesions (HSILs), respectively. Investigation of HSIL POCkeT images revealed decreased visibility of vascularization and lack of contrast in lesion margins. After changes were made for the second protocol, the 2 devices achieved similar agreement to pathology for HSIL lesions (55%). CONCLUSIONS: Based on the exploratory study, physician interpretation of cervix images acquired using a portable, low-cost POCkeT colposcope was comparable to a standard-of-care colposcope.


Asunto(s)
Colposcopios , Colposcopía/métodos , Detección Precoz del Cáncer/métodos , Imagen Óptica/métodos , Sistemas de Atención de Punto , Adolescente , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Nivel de Atención , Neoplasias del Cuello Uterino/diagnóstico , Adulto Joven
20.
Health Commun ; 32(3): 347-355, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27268509

RESUMEN

Online support groups are attractive to individuals suffering from various types of mental and physical illness due to their accessibility, convenience, and comfort level. Individuals coping with depression, in particular, may seek social support online to avoid the stigma that accompanies face-to-face support groups. We explored how task and relational messages created social support in online depression support groups using Cutrona and Suhr's social support coding scheme and Bales's Interaction Process Analysis coding scheme. A content analysis revealed emotional support as the most common type of social support within the group, although the majority of messages were task rather than relational. Informational support consisted primarily of task messages, whereas network and esteem support were primarily relational messages. Specific types of task and relational messages were associated with different support types. Results indicate task messages dominated online depression support groups, suggesting the individuals who participate in these groups are interested in solving problems but may also experience emotional support when their uncertainty is reduced via task messages.


Asunto(s)
Adaptación Psicológica , Internet , Grupos de Autoayuda/estadística & datos numéricos , Depresión/psicología , Comunicación en Salud , Humanos , Conducta en la Búsqueda de Información , Investigación Cualitativa
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