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1.
Gynecol Minim Invasive Ther ; 13(1): 19-24, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487616

RESUMEN

Objectives: Surgery for pregnant women with ovarian tumors poses the risk of uterine irritation. We aimed to demonstrate the superiority of our laparoscopic technique over conventional methods and to compare the outcomes of laparoscopy with those of laparotomy for ovarian tumors during pregnancy. Materials and Methods: This retrospective study included 50 patients undergoing procedures for ovarian tumors during pregnancy at the Tokushima University Hospital between January 2005 and December 2021. We compared surgical outcomes between laparoscopic procedures and laparotomy, along with complications. In addition, we compared the frequency of uterine stimulation with the conventional trocar position to that with the currently used trocar position in laparoscopic surgery. Results: Forty patients in the laparoscopy group and 10 in the laparotomy group underwent procedures. The laparoscopy group had less bleeding (16.4 ± 28.8 vs. 58 ± 72.2 mL, P < 0.05) and shorter hospital stays (7.6 ± 1.7 vs. 12.8 ± 13.1 days, P < 0.05) compared with those of the laparotomy group. The outcomes showed no significant differences between groups. All laparoscopies and laparotomies were successful and without complications. Furthermore, the current trocar position tended to stimulate the uterus less frequently. Conclusion: The results suggested that, compared to laparotomy, laparoscopy for ovarian tumors during pregnancy had better outcomes. The trocar position in our technique allows for easy operation of ovarian tumors without interference by forceps or cameras, resulting in minimal irritation of the uterus. Our original laparoscopic method may be safer with superior outcomes over the conventional method.

3.
Steroids ; 203: 109367, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266463

RESUMEN

While the effects of progesterone on body weight and appetite in pre-menopausal conditions have been well elucidated, its effects in post-menopausal conditions have not been clarified. On the contrary, the effects of estrogen on body weight and appetite in post-menopausal conditions have been well established. In this study, the effects of progesterone treatment on body weight, appetite, and fat mass in ovariectomized rats were evaluated. In addition, the central and/or peripheral levels of oxytocin (OT), leptin, and their receptors, which are potent anorectic factors, were examined. Female rats were ovariectomized and divided into control, progesterone-treated, and estrogen-treated groups. Body weight, food intake, and subcutaneous fat mass were lower in both the progesterone and estrogen groups than in the control group. The estrogen group exhibited higher serum OT levels than the control group, whereas the OT levels of the progesterone and control groups did not differ. The serum leptin levels of both the progesterone and estrogen groups were lower than those of the control group. Gene expression analysis of OT, leptin, and their receptors in the hypothalamus and adipose tissue found few significant differences among the groups. Hypothalamic neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) mRNA levels involved in appetite regulation were slightly altered in the progesterone and estrogen groups. These findings suggest that progesterone treatment may have favorable effects on body weight, appetite, and fat mass regulation in post-menopausal conditions and that the mechanisms underlying these effects of progesterone differ from those underlying the effects of estrogen.


Asunto(s)
Leptina , Progesterona , Ratas , Animales , Femenino , Leptina/metabolismo , Progesterona/farmacología , Progesterona/metabolismo , Ingestión de Alimentos , Peso Corporal , Hipotálamo , Proteínas Portadoras , Estrógenos/farmacología , Estrógenos/metabolismo , Proopiomelanocortina/genética , Proopiomelanocortina/metabolismo , Proopiomelanocortina/farmacología
4.
Int J Mol Sci ; 24(23)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38068890

RESUMEN

In recent years, the effects of androgens on metabolic and body weight regulation systems and their underlying mechanisms have been gradually revealed in females. In women and experimental animals of reproductive age, androgen excess can adversely affect metabolic functioning, appetite, and body weight regulation. In addition, excess androgens can increase the risk of metabolic disorders, such as obesity, insulin resistance, and diabetes. These unfavorable effects of androgens are induced by alterations in the actions of hypothalamic appetite-regulatory factors, reductions in energy expenditure, insulin resistance in skeletal muscle, and ß-cell dysfunction. Interestingly, these unfavorable effects of androgens on metabolic and body-weight regulation systems are neither observed nor evident in ovariectomized animals and post-menopausal women, indicating that the adverse effects of androgens might be dependent on the estrogen milieu. Recent findings may provide novel sex- and age-specific strategies for treating metabolic diseases.


Asunto(s)
Resistencia a la Insulina , Enfermedades Metabólicas , Síndrome del Ovario Poliquístico , Animales , Humanos , Femenino , Andrógenos/farmacología , Andrógenos/metabolismo , Resistencia a la Insulina/fisiología , Obesidad/metabolismo , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/metabolismo , Animales de Laboratorio/metabolismo , Síndrome del Ovario Poliquístico/metabolismo
5.
Nutrients ; 15(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37375670

RESUMEN

Changes in the activities of some metabolic factors have been suggested to increase the risk of conditions associated with the Developmental Origins of Health and Disease (DOHaD). We examined changes in oxytocin (OT), a metabolic factor, and OT receptor (OTR) mRNA levels throughout the developmental period in rats of intrauterine undernutrition. Pregnant rats were divided into two groups: a maternal normal nutrition (mNN) and maternal undernutrition (mUN) group. Serum OT concentrations and hypothalamic mRNA levels of OT and OTR were measured in both offspring at various postnatal stages. Both offspring showed significant increases in serum OT concentrations during the neonatal period, significant reductions around the pubertal period, and significant increases in adulthood. Hypothalamic OT mRNA expression levels gradually increased from the neonatal to pubertal period and decreased in adulthood in both offspring. In the pre-weaning period, hypothalamic OT mRNA expression levels were significantly lower in the mUN offspring than in the mNN offspring. In the mUN offspring, hypothalamic OTR mRNA expression levels transiently increased during the neonatal period, decreased around the pubertal period, and increased again in adulthood, whereas transient changes were not detected in mNN offspring. These changes could affect nutritional and metabolic regulation systems in later life and play a role in the mechanisms underlying DOHaD.


Asunto(s)
Desnutrición , Oxitocina , Embarazo , Femenino , Ratas , Animales , Ratas Sprague-Dawley , Desnutrición/complicaciones , Destete , ARN Mensajero/metabolismo
6.
Endocr J ; 69(12): 1363-1372, 2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36372440

RESUMEN

It has been well established that undernutrition and low energy availability disturb female reproductive functions in humans and many animal species. These reproductive dysfunctions are mainly caused by alterations of some hypothalamic factors, and consequent reduction of gonadotrophin-releasing hormone (GnRH) secretion. Evidence from literature suggests that increased activity of orexigenic factors and decreased activity of anorexigenic/satiety-related factors in undernourished conditions attenuate GnRH secretion in an integrated manner. Likewise, the activity of kisspeptin neurons, which is a potent stimulator of GnRH, is also reduced in undernourished conditions. In addition, it has been suggested that gonadotrophin-inhibitory hormone, which has anti-GnRH and gonadotrophic effects, may be involved in reproductive dysfunctions under several kinds of stress conditions. It should be remembered that these alterations, i.e., promotion of feeding behavior and temporary suppression of reproductive functions, are induced to prioritize the survival of individual over that of species, and that improvements in metabolic and nutritional conditions should be considered with the highest priority.


Asunto(s)
Hormona Liberadora de Gonadotropina , Desnutrición , Animales , Femenino , Humanos , Gonadotropinas , Hipotálamo/metabolismo , Kisspeptinas/fisiología
7.
Mol Clin Oncol ; 16(1): 24, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34909202

RESUMEN

Although endometrial cancer is extremely rare during pregnancy, the placental metastasis of endometrial cancer is even rarer. The current study presents a case of endometrial carcinoma that was diagnosed through the pathological examination of the placenta. A 35-year-old primipara woman who underwent frozen-thawed embryo transfer at the Keiai Ladies Clinic in Tokushima prefecture (Japan) received regular prenatal check-ups. She was transferred to Tokushima University Hospital for perinatal management due to the preterm premature rupture of membranes at 21 weeks and 6 days gestation. The administration of antibiotics and tocolytic agents was continued; however, labor pain occurred at 23 weeks and 3 days gestation, and a female fetus weighing 524 g was delivered vaginally. The placenta weighed 262 g and had no macroscopic abnormalities. It was submitted for pathological examination, which revealed metastatic adenocarcinoma (clear cell carcinoma suspected). The patient was subsequently diagnosed with endometrial cancer (stage I suspected), and underwent abdominal total hysterectomy, bilateral salpingo-oophorectomy, partial omentectomy and pelvic lymph node dissection. The final diagnosis was stage IA endometrial cancer (endometrioid carcinoma, G2). At 1 year after surgery, there was no evidence of disease. The present case highlights the importance of considering the emergence of endometrial cancer during pregnancy.

8.
Gen Comp Endocrinol ; 288: 113360, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31830472

RESUMEN

PURPOSE: We examined the mechanism by which neonatal immune stress reduces the sexual behavior of female rats in adulthood. METHODS: Neonatal female rats were randomly divided into 3 groups: control (n = 11), postnatal day 10 lipopolysaccharide (PND10LPS) (n = 23), and PND25LPS (n = 11) groups, which received intraperitoneal injections of LPS (100 µg/kg) or saline on PND10 and 25. Daily inspections of the vaginal opening (VO) were performed from PND27 to PND37. Thereafter, the frequency of estrus was assessed for 15 days. Female rats (at 11-12 weeks of age) were placed in a cage with male rats, and their sexual behavior was monitored for 30 min. The hypothalamic mRNA expression levels of factors related to sexual behavior were examined via real-time PCR. RESULTS: VO occurred later and the frequency of estrus was lower in the PND10LPS group compared to the control group. The number of lordosis behaviors and the total number of mounts performed by male partners were lower in the PND10LPS and PND25LPS groups than in the control group. Acceptability: The lordosis quotient and lordosis rating were lower in the PND10LPS group than in the control group. Proceptive behavior: the number of ear wiggling events was lower in the PND10LPS group than in the other groups, and the number of hops/darts was lower in the PND10LPS group than in the control group. The hypothalamic mRNA expression level of progesterone receptors (PR)A + B was lower in the PND10LPS group than in the control group, and the hypothalamic PRB mRNA expression level was lower in the PND10LPS and PND25LPS groups than in the control group. CONCLUSION: Neonatal immune stress impeded sexual behavior and hypothalamic PR mRNA expression in female rats. Decreased progesterone activity in the hypothalamus might explain the reduction in sexual behavior seen in these rats.


Asunto(s)
Hipotálamo/metabolismo , Lipopolisacáridos/administración & dosificación , Receptores de Progesterona/genética , Conducta Sexual Animal/efectos de los fármacos , Conducta Sexual Animal/fisiología , Estrés Fisiológico/inmunología , Factores de Edad , Animales , Animales Recién Nacidos , Regulación hacia Abajo/efectos de los fármacos , Esquema de Medicación , Femenino , Expresión Génica/efectos de los fármacos , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/fisiopatología , Lipopolisacáridos/farmacología , Masculino , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores de Progesterona/metabolismo , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Factores de Tiempo
9.
J Vis Exp ; (138)2018 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-30199019

RESUMEN

This protocol describes how to make agarose-based tissue-mimicking phantoms and demonstrates how to determine their optical properties using a conventional optical system with an integrating sphere. Measuring systems for the acquisition of the diffuse reflectance and total transmittance spectra are constructed with a broadband white light source, a light guide, an achromatic lens, an integrating sphere, a sample holder, an optical fiber probe, and a multi-channel spectrometer. An acrylic mold consisting of two rectangular acrylic pieces and a U-shaped acrylic piece is constructed to create an epidermal phantom and a dermal phantom with whole blood. The application of a sodium dithionite (Na2S2O4) solution to the dermal phantom enables the researcher to deoxygenate hemoglobin in red blood cells distributed in the dermal phantom. The inverse Monte Carlo simulation with the diffuse reflectance and total transmittance spectra measured by a spectrometer with an integrating sphere is performed to determine the absorption coefficient spectrum µa(λ) and the reduced scattering coefficient spectrum µs'(λ) of each layer phantom. A two-layered phantom mimicking the diffuse reflectance of human skin tissue is also demonstrated by piling up the epidermal phantom on the dermal phantom.


Asunto(s)
Análisis Espectral/métodos , Humanos , Modelos Biológicos , Dispersión de Radiación , Sefarosa
10.
Sensors (Basel) ; 13(6): 7902-15, 2013 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-23783740

RESUMEN

A multi-spectral diffuse reflectance imaging method based on a single snap shot of Red-Green-Blue images acquired with the exposure time of 65 ms (15 fps) was investigated for estimating melanin concentration, blood concentration, and oxygen saturation in human skin tissue. The technique utilizes the Wiener estimation method to deduce spectral reflectance images instantaneously from an RGB image. Using the resultant absorbance spectrum as a response variable and the extinction coefficients of melanin, oxygenated hemoglobin and deoxygenated hemoglobin as predictor variables, multiple regression analysis provides regression coefficients. Concentrations of melanin and total blood are then determined from the regression coefficients using conversion vectors that are numerically deduced in advance by the Monte Carlo simulations for light transport in skin. Oxygen saturation is obtained directly from the regression coefficients. Experiments with a tissue-like agar gel phantom validated the method. In vivo experiments on fingers during upper limb occlusion demonstrated the ability of the method to evaluate physiological reactions of human skin.


Asunto(s)
Hemoglobinas/análisis , Melaninas/análisis , Espectrofotometría , Humanos , Melaninas/sangre , Método de Montecarlo , Oxígeno/metabolismo , Análisis de Regresión , Piel/metabolismo
11.
J Biomed Opt ; 18(6): 061220, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23748701

RESUMEN

We propose a method to visualize the arterial inflow, the vascular resistance, and the venous capacitance in the skin tissue from red, green, blue (RGB) digital color images. The arterial inflow and the venous capacitance in the skin tissue are visualized based on an increase in the rate of change in the total blood concentration and the change of the total blood concentration during upper limb occlusion at a pressure of 50 mmHg. The resultant arterial inflow with the measured mean arterial pressure also provides an image of the vascular resistance in human skin. The arterial inflow, the vascular resistance, and the venous capacitance acquired by the method are well correlated with those obtained from the conventional strain-gauge plethysmograph. The correlation coefficients R between the estimated values by the method and the measurements by the SPG are calculated to be 0.83 (P<0.001) for the arterial inflow, 0.77 (P<0.01) for the vascular resistance, and 0.77 (P<0.01) for the venous capacitance. The arterial inflow and the venous capacitance in the skin tissue are significantly higher in active subjects compared with the sedentary subjects, whereas the vascular resistance was significantly lower in the active subjects compared with the sedentary subjects. The results of the present study indicate the possibility of using the proposed method for evaluating the peripheral vascular functions in human skin.


Asunto(s)
Piel/irrigación sanguínea , Piel/patología , Vasodilatación , Algoritmos , Presión Arterial , Arterias/patología , Color , Antebrazo/irrigación sanguínea , Humanos , Flujometría por Láser-Doppler , Luz , Pletismografía , Presión , Flujo Sanguíneo Regional , Análisis de Regresión , Resistencia Vascular
12.
J Biomed Opt ; 18(6): 061220, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23264964

RESUMEN

We propose a method to visualize the arterial inflow, the vascular resistance, and the venous capacitance in the skin tissue from red, green, blue (RGB) digital color images. The arterial inflow and the venous capacitance in the skin tissue are visualized based on an increase in the rate of change in the total blood concentration and the change of the total blood concentration during upper limb occlusion at a pressure of 50 mmHg. The resultant arterial inflow with the measured mean arterial pressure also provides an image of the vascular resistance in human skin. The arterial inflow, the vascular resistance, and the venous capacitance acquired by the method are well correlated with those obtained from the conventional strain-gauge plethysmograph. The correlation coefficients R between the estimated values by the method and the measurements by the SPG are calculated to be 0.83 (P < 0.001) for the arterial inflow, 0.77 (P < 0.01) for the vascular resistance, and 0.77 (P < 0.01) for the venous capacitance. The arterial inflow and the venous capacitance in the skin tissue are significantly higher in active subjects compared with the sedentary subjects, whereas the vascular resistance was significantly lower in the active subjects compared with the sedentary subjects. The results of the present study indicate the possibility of using the proposed method for evaluating the peripheral vascular functions in human skin.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Piel/irrigación sanguínea , Simulación por Computador , Mano/irrigación sanguínea , Humanos , Método de Montecarlo , Fotograbar , Análisis de Regresión , Piel/química , Capacitancia Vascular/fisiología , Resistencia Vascular/fisiología
13.
Mech Dev ; 128(11-12): 625-39, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22198363

RESUMEN

Many animals develop left-right (LR) asymmetry in their internal organs. The mechanisms of LR asymmetric development are evolutionarily divergent, and are poorly understood in invertebrates. Therefore, we studied the genetic pathway of LR asymmetric development in Drosophila. Drosophila has several organs that show directional and stereotypic LR asymmetry, including the embryonic gut, which is the first organ to develop LR asymmetry during Drosophila development. In this study, we found that genes encoding components of the Wnt-signaling pathway are required for LR asymmetric development of the anterior part of the embryonic midgut (AMG). frizzled 2 (fz2) and Wnt4, which encode a receptor and ligand of Wnt signaling, respectively, were required for the LR asymmetric development of the AMG. arrow (arr), an ortholog of the mammalian gene encoding low-density lipoprotein receptor-related protein 5/6, which is a co-receptor of the Wnt-signaling pathway, was also essential for LR asymmetric development of the AMG. These results are the first demonstration that Wnt signaling contributes to LR asymmetric development in invertebrates, as it does in vertebrates. The AMG consists of visceral muscle and an epithelial tube. Our genetic analyses revealed that Wnt signaling in the visceral muscle but not the epithelium of the midgut is required for the AMG to develop its normal laterality. Furthermore, fz2 and Wnt4 were expressed in the visceral muscles of the midgut. Consistent with these results, we observed that the LR asymmetric rearrangement of the visceral muscle cells, the first visible asymmetry of the developing AMG, did not occur in embryos lacking Wnt4 expression. Our results also suggest that canonical Wnt/ß-catenin signaling, but not non-canonical Wnt signaling, is responsible for the LR asymmetric development of the AMG. Canonical Wnt/ß-catenin signaling is reported to have important roles in LR asymmetric development in zebrafish. Thus, the contribution of canonical Wnt/ß-catenin signaling to LR asymmetric development may be an evolutionarily conserved feature between vertebrates and invertebrates.


Asunto(s)
Sistema Digestivo/embriología , Drosophila melanogaster/embriología , Músculo Liso/embriología , Vía de Señalización Wnt , Animales , Análisis Mutacional de ADN , Sistema Digestivo/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Regulación del Desarrollo de la Expresión Génica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Músculo Liso/citología , Músculo Liso/metabolismo , Mutación , Miocitos del Músculo Liso/metabolismo , Especificidad de Órganos , Organogénesis , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
14.
J Biomed Opt ; 16(8): 086012, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21895324

RESUMEN

In order to visualize human skin hemodynamics, we investigated a method that is specifically developed for the visualization of concentrations of oxygenated blood, deoxygenated blood, and melanin in skin tissue from digital RGB color images. Images of total blood concentration and oxygen saturation can also be reconstructed from the results of oxygenated and deoxygenated blood. Experiments using tissue-like agar gel phantoms demonstrated the ability of the developed method to quantitatively visualize the transition from an oxygenated blood to a deoxygenated blood in dermis. In vivo imaging of the chromophore concentrations and tissue oxygen saturation in the skin of the human hand are performed for 14 subjects during upper limb occlusion at 50 and 250 mm Hg. The response of the total blood concentration in the skin acquired by this method and forearm volume changes obtained from the conventional strain-gauge plethysmograph were comparable during the upper arm occlusion at pressures of both 50 and 250 mm Hg. The results presented in the present paper indicate the possibility of visualizing the hemodynamics of subsurface skin tissue.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Fotograbar/métodos , Pigmentación de la Piel/fisiología , Piel/irrigación sanguínea , Adolescente , Adulto , Brazo , Monitoreo de Gas Sanguíneo Transcutáneo , Femenino , Hemodinámica/fisiología , Hemoglobinas/análisis , Humanos , Masculino , Melaninas/análisis , Modelos Biológicos , Método de Montecarlo , Oxihemoglobinas/análisis , Fantasmas de Imagen , Pletismografía , Piel/química , Oclusión Terapéutica
15.
Opt Lett ; 36(16): 3239-41, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21847220

RESUMEN

In order to visualize melanin and blood concentrations and oxygen saturation in human skin tissue, a simple imaging technique based on multispectral diffuse reflectance images acquired at six wavelengths (500, 520, 540, 560, 580 and 600 nm) was developed. The technique utilizes multiple regression analysis aided by Monte Carlo simulation for diffuse reflectance spectra. Using the absorbance spectrum as a response variable and the extinction coefficients of melanin, oxygenated hemoglobin, and deoxygenated hemoglobin as predictor variables, multiple regression analysis provides regression coefficients. Concentrations of melanin and total blood are then determined from the regression coefficients using conversion vectors that are deduced numerically in advance, while oxygen saturation is obtained directly from the regression coefficients. Experiments with a tissue-like agar gel phantom validated the method. In vivo experiments with human skin of the human hand during upper limb occlusion and of the inner forearm exposed to UV irradiation demonstrated the ability of the method to evaluate physiological reactions of human skin tissue.


Asunto(s)
Imagen Molecular/métodos , Método de Montecarlo , Pigmentación de la Piel , Piel/metabolismo , Análisis Espectral , Sangre/metabolismo , Humanos , Masculino , Melaninas/metabolismo , Oxígeno/metabolismo , Análisis de Regresión , Adulto Joven
16.
Opt Lett ; 33(19): 2263-5, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18830372

RESUMEN

A method is proposed for visualizing simply the concentrations of melanin, oxygenated blood, and deoxygenated blood in skin tissue using digital RGB images. The total blood concentration and oxygen saturation can also be reconstructed. Monte Carlo simulation of light transport specifies a relation between the chromophore concentrations and Commission Internationale de l'Eclairage XYZ, which are compatible with the common RGB working space. Experiments with a tissuelike agar gel phantom demonstrated the possibility of the method. In vivo imaging of a human hand during forearm occlusion demonstrated the ability of the method to evaluate hemodynamics of skin tissue.


Asunto(s)
Colorimetría/métodos , Dermoscopía/métodos , Fotometría/métodos , Pigmentación de la Piel/fisiología , Humanos
17.
J Biomed Opt ; 12(5): 054006, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17994894

RESUMEN

A method is proposed for visualizing the depth and thickness distribution of a local blood region in skin tissue using diffuse reflectance images at three isosbestic wavelengths of hemoglobin: 420, 585, and 800 nm. Monte Carlo simulation of light transport specifies a relation among optical densities, depth, and thickness of the region under given concentrations of melanin in epidermis and blood in dermis. Experiments with tissue-like agar gel phantoms indicate that a simple circular blood region embedded in scattering media can be visualized with errors of 6% for the depth and 22% for the thickness to the given values. In-vivo measurements on human veins demonstrate that results from the proposed method agree within errors of 30 and 19% for the depth and thickness, respectively, with values obtained from the same veins by the conventional ultrasound technique. Numerical investigation with the Monte Carlo simulation of light transport in the skin tissue is also performed to discuss effects of deviation in scattering coefficients of skin tissue and absorption coefficients of the local blood region from the typical values of the results. The depth of the local blood region is over- or underestimated as the scattering coefficients of epidermis and dermis decrease or increase, respectively, while the thickness of the region agrees well with the given values below 1.2 mm. Decreases or increases of hematocrit value give over- or underestimation of the thickness, but they have almost no influence on the depth.


Asunto(s)
Vasos Sanguíneos/citología , Interpretación de Imagen Asistida por Computador/métodos , Fotometría/métodos , Piel/irrigación sanguínea , Piel/citología , Tomografía Óptica/métodos , Humanos , Fantasmas de Imagen , Fotometría/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Óptica/instrumentación
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