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1.
J Food Sci ; 88(10): 4180-4193, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37655508

RESUMO

Accurate classification and identification of chicken parts are critical to improve the productivity and processing speed in poultry processing plants. However, the overlapping of chicken parts has an impact on the effectiveness of the identification process. To solve this issue, this study proposed a real-time classification and detection method for chicken parts, utilizing YOLOV4 deep learning. The method can identify segmented chicken parts on the assembly line in real time and accurately, thus improving the efficiency of poultry processing. First, 600 images containing multiple chicken part samples were collected to build a chicken part dataset after using the image broadening technique, and then the dataset was divided according to the 6:2:2 division principle, with 1200 images as the training set, 400 images as the test set, and 400 images as the validation set. Second, we utilized the single-stage target detector YOLO to predict and calculate the chicken part images, obtaining the categories and positions of the chicken leg, chicken wing, and chicken breast in the image. This allowed us to achieve real-time classification and detection of chicken parts. This approach enabled real-time and efficient classification and detection of chicken parts. Finally, the mean average precision (mAP) and the processing time per image were utilized as key metrics to evaluate the effectiveness of the model. In addition, four other target detection algorithms were introduced for comparison with YOLOV4-CSPDarknet53 in this study, which include YOLOV3-Darknet53, YOLOV3-MobileNetv3, SSD-MobileNetv3, and SSD-VGG16. A comprehensive comparison test was conducted to assess the classification and detection performance of these models for chicken parts. Finally, for the chicken part dataset, the mAP of the YOLOV4-CSPDarknet53 model was 98.86% on a single image with an inference speed of 22.2 ms, which was higher than the other four models of YOLOV3-Darknet53, YOLOV3-MobileNetv3, SSD-MobileNetv3, and SSD-VGG16 mAP by 3.27%, 3.78%, 6.91%, and 6.13%, respectively. The average detection time was reduced by 13, 1.9, 6.2, and 20.3 ms, respectively. In summary, the chicken part classification and detection method proposed in this study offers numerous benefits, including the ability to detect multiple chicken parts simultaneously, as well as delivering high levels of accuracy and speed. Furthermore, this approach effectively addresses the issue of accurately identifying individual chicken parts in the presence of occlusion, thereby reducing waste on the assembly line. PRACTICAL APPLICATION: The aim of this study is to offer visual technical assistance in minimizing wastage and resource depletion during the sorting and cutting of chicken parts in poultry production and processing facilities. Furthermore, considering the diverse demands and preferences regarding chicken parts, this research can facilitate product processing that caters specifically to consumer preferences.


Assuntos
Aprendizado Profundo , Animais , Algoritmos , Movimento Celular , Velocidade de Processamento
2.
Front Neurosci ; 17: 1186053, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37650098

RESUMO

Objectives: Cranial magnetic resonance imaging (MRI) could be a crucial tool for the assessment for neurological symptoms in patients with Wilson's disease (WD). Diffusion-weighted imaging (DWI) hyperintensity reflects the acute brain injuries, which mainly occur in specific brain regions. Therefore, this study aimed to develop a weighted cranial DWI scale for patients with WD, with special focus on specific brain regions. Materials and methods: In total, 123 patients with WD were enrolled, 118 of whom underwent 1.5 T-MRI on admission. The imaging score was calculated as described previously and depended on the following sequences: one point was acquired when abnormal intensity occurred in the T1, T2, and fluid-attenuation inversion recovery sequences, and two points were acquired when DWI hyperintensity were found. Consensus weighting was conducted based on the symptoms and response to treatment. Results: Intra-rater agreement were good (r = 0.855 [0.798-0.897], p < 0.0001). DWI hyperintensity in the putamen was a high-risk factor for deterioration during de-copper therapy (OR = 8.656, p < 0.05). The high-risk factors for readmission for intravenous de-copper therapies were DWI hyperintensity in the midbrain (OR = 3.818, p < 0.05) and the corpus callosum (OR = 2.654, p < 0.05). Both scoring systems had positive correlation with UWDRS scale (original semi-quantitative scoring system, r = 0.35, p < 0.001; consensus semi-quantitative scoring system, r = 0.351, p < 0.001.). Compared to the original scoring system, the consensus scoring system had higher correlations with the occurrence of deterioration (OR = 1.052, 95%CI [1.003, 1.0103], p < 0.05) and readmission for intravenous de-copper therapy (OR = 1.043, 95%CI [1.001, 1.086], p < 0.05). Conclusion: The predictive performance of the consensus semi-quantitative scoring system for cranial MRI was improved to guide medication, healthcare management, and prognosis prediction in patients with WD. For every point increase in the neuroimaging score, the risk of exacerbations during treatment increased by 5.2%, and the risk of readmission to the hospital within 6 months increased by 4.3%.

3.
Anim Sci J ; 92(1): e13556, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33973682

RESUMO

The effect of alfalfa saponins (AS) supplementation on the meat quality especially the color for growing lamb was investigated. Fifty Hu male lambs with body weights (BW, 19.21 ± 0.45 kg) were divided into five groups and supplemented AS with 0, 500, 1,000, 2,000, and 4,000 mg/kg of dietary dry matter intake. After 90 days, all lambs were slaughtered. The longissimus thoracis muscle in lamb displayed significant changes in the content of intramuscular fat, especially n-3 polyunsaturated fatty acids, and drip loss within AS treatment (p < .05) between control and treatments groups. Redness (a*) significantly improved in both 0-day and 7-day storage with the AS supplementation coupled with the percentage of met-myoglobin reduction (p < .05). The redness (a*) change may result from improved met-myoglobin reducing activity, antioxidant enzymes, lactate dehydrogenase, and succinate dehydrogenase (p < .05) by AS supplementation in muscle. These enzymes may help to protect mitochondria function and reduce met-myoglobin, which bring a bright and red meat color.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cor , Dieta/veterinária , Suplementos Nutricionais , Qualidade dos Alimentos , Carne , Medicago sativa/química , Músculo Esquelético/metabolismo , Mioglobina/metabolismo , Saponinas/administração & dosagem , Ovinos/crescimento & desenvolvimento , Ovinos/metabolismo , Tecido Adiposo/metabolismo , Animais , Ácidos Graxos Ômega-3/metabolismo , Armazenamento de Alimentos/métodos , Masculino , Carne/análise , Saponinas/isolamento & purificação , Fatores de Tempo
4.
Antioxidants (Basel) ; 10(2)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33573002

RESUMO

This study was designed to investigate the impact of dietary lycopene (antioxidant extracted from tomato) supplementation on postmortem antioxidant capacity, drip loss and protein expression profiles of lamb meat during storage. Thirty male Hu lambs were randomly divided into three treatment groups and housed in individual pens and received 0, 200 or 400 mg·kg-1 lycopene in their diet, respectively. All lambs were slaughtered after 3 months of fattening, and the longissimus thoracis (LT) muscle was collected for analyses. The results indicated that drip loss of LT muscle increased with storage days (P < 0.05). After storage for 7 days, significantly lower drip loss of meat was found in fed the lycopene-supplemented diet (P < 0.05). Dietary lycopene supplementation increased the activity of antioxidant enzymes (total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT)) (P < 0.05) and decreased the thiobarbituric acid reactive substance (TBARS) and carbonyl contents (P < 0.05). During the storage period (days 0, 5 and 7), a number of differentially abundant proteins (DAPs), including oxidases, metabolic enzymes, calcium channels and structural proteins, were identified based on iTRAQ data, with roles predominantly in carbon metabolism, oxidative phosphorylation, cardiac muscle contraction and proteasome pathways, and which contribute to decreased drip loss of lamb meat during storage. It can be concluded that dietary lycopene supplementation increased antioxidant capacity after slaughter, and the decreased drip loss during postmortem storage might occur by changing the expression of proteins related to enzyme activity and cellular structure in lamb muscle.

6.
J Ophthalmol ; 2020: 4835630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32724668

RESUMO

The novel coronavirus pneumonia COVID-19 is caused by the novel coronavirus SARS-CoV-2, which is highly contagious, has a long incubation period, and can be detected in patients' tears and conjunctival secretions. In this study, we describe our experience regarding the necessary protective measures that need to be taken during ophthalmic examination and treatment. The authors reviewed the clinical work arrangements during the epidemic situation at the Eye Hospital of Wenzhou Medical University in China and analyzed the prevention and control measures that were applied during the laser corneal refractive surgery process. The comprehensive protection protocol, which was established throughout the entire process, included both horizontal (medical staff-patient, medical staff-medical staff, and patient-patient) and vertical (preoperative, intraoperative, and postoperative transmission assessment) approach and was mainly focused on strengthening the protection against potential aerosol transmission that may occur during intraocular pressure measurements and laser ablation. The described and proposed protocol, along with the further guidelines followed by the medical personnel, proved to be efficacious and contributed significantly to the control of the COVID-19 outbreak and the protection of both the patients and the medical staff.

7.
Foods ; 9(6)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575353

RESUMO

This study was performed to compare the differences in pH, myofibril fragmentation index (MFI), total protein solubility (TPS), sarcoplasmic protein solubility (SPS), myofibrillar protein solubility (MPS), and the microstructure of seven beef muscles during aging. From the six beef carcasses of Xinjiang brown cattle, a total of 252 samples from semitendinosus (ST), longissimus thoracis (LT), rhomboideus (RH), gastrocnemius (GN), infraspinatus (IN), psoas major (PM), and biceps femoris (BF) muscles were collected, portioned, and assigned to six aging periods (1, 3, 7, 9, 11, and 14 day/s) and 42 samples were used per storage period. IN muscle showed the highest pH (p < 0.05) from 1 to 14 days and the lowest TPS (p < 0.01) from 9 to 14 days with respect to the other muscles. Moreover, the changes in IN were further supported by transmission electron microscopy due to the destruction of the myofibril structure. The highest value of MFI was tested in ST muscle from 7 to 14 days. The total protein solubility in PM, RH, and GN muscles were not affected (p > 0.05) as the aging period increased. The lowest TPS was found in the RH muscle on day 1, 3, and 7 and in the IN muscle on day 9, 11, and 14. The pH showed negative correlations with the MFI, TPS, and MPS (p < 0.01). The results suggest that changes in protein solubility and muscle fiber structure are related to muscle location in the carcass during aging. These results provide new insights to optimize the processing and storage of different beef muscles and enhance our understanding of the biological characteristics of Xinjiang brown cattle muscles.

8.
Foods ; 9(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290142

RESUMO

The purpose was to investigate the quality characteristics of dry-cured beef with different storage times under a high-voltage electrostatic field (HVEF) condition. The pH, moisture content, meat color, and volatile compounds of dry-cured beef samples treated with HVEF (3 kV) were compared with those of a common refrigerator (CON) at days 0, 3, 7, 10, and 14. The results showed that, compared with CON group, the decline rates of the pH and moisture content of beef and ∆E values were lower under HVEF storage condition. From the fingerprints, the 42 volatile compounds identified were mainly aldehydes, alcohols, ketones, and esters. The benzaldehyde, trimethyl pyrazine, and maltol contents in the HVEF group exhibited a dramatic increase after 10 days of storage. Principal component analysis revealed clustering of compound classes, distributed in a separate time. Based on the above findings, we concluded that HVEF treatment could promote color stability and enhance characteristic flavor during the storage of dry-cured beef. These results suggested that HVEF might be applicable for dry-cured meat storage techniques.

9.
Anim Reprod Sci ; 205: 52-61, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005359

RESUMO

Dietary vitamin E supplementation is beneficial to semen quality in different sheep and goat breeds. The aim of this research was to further investigate the effect of vitamin E in sheep on spermatogenesis and its regulatory mechanisms using RNA-seq. Thirty male Hu lambs were randomly divided into three groups. The animals received 0, 200 or 2000 IU/day vitamin E dietary supplementation for 105 days, and its effects were subsequently evaluated. The results indicate vitamin E supplementation increased the number of germ cells in the testes and epididymides. The positive effects were reduced, however, in animals that received 2000 IU/d vitamin E. Using the RNA-seq procedure, there was detection of a number of differentially expressed genes such as NDRG1, FSCN3 and CYP26B1 with these genes being mainly related to the regulation of spermatogenesis. Supplementation with 2000 IU/d vitamin E supplementation resulted in a lesser abundance of skeleton-related transcripts such as TUBB, VIM and different subtypes of collagen, and there was also an effect on the ECM-receptor interaction pathway. These changes appear to be responsible for the lesser beneficial effect of the greater vitamin E concentrations. The results provide a novel insight into the regulation of spermatogenesis by vitamin E at the molecular level, however, for a precise understanding of functions of the affected genes there needs to be further study.


Assuntos
Dieta/veterinária , Análise do Sêmen/veterinária , Ovinos , Espermatogênese/fisiologia , Testículo/efeitos dos fármacos , Vitamina E/farmacologia , Ração Animal/análise , Animais , Antioxidantes , Suplementos Nutricionais , Masculino , Distribuição Aleatória , Espermatogênese/efeitos dos fármacos , Testículo/metabolismo
10.
Acta Ophthalmol ; 96(2): e127-e133, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29064187

RESUMO

PURPOSE: To evaluate the posterior corneal surface differences between non-laser in situ keratomileusis (LASIK) and 10-year post-LASIK myopic eyes. METHODS: The study included 130 eyes from 65 patients, who were treated with myopic LASIK 10 years ago. In addition, 130 eyes from 65 unoperated myopic patients of matching present age and preoperative refraction were divided into control group. Data on the posterior corneal surface and anterior chamber were obtained from Pentacam software and compared between the groups. Postoperative visual acuity (VA) and refractive error were also analysed. RESULTS: The mean preoperative spherical equivalent (SE) was -6.99 ± 1.78 dioptre (D) in the LASIK group. Ten years after surgery, the mean SE was -0.45 ± 1.22 D, the efficacy index was 0.98, and the safety index was 1.01. The posterior corneal elevations of the LASIK group at 2 mm corneal diameter were significantly lower than those of the control group. However, posterior corneal elevations at 6 mm corneal diameter were higher in the LASIK group than the controls (p < 0.01 for all). The mean Q-values of posterior corneal surface demonstrated significant positive direction compared to that of control eyes at 6 and 7 mm corneal diameters (p < 0.05 for both). At the thinnest point of the cornea, the anterior chamber depths were shallower in the LASIK group than in controls. Meanwhile, the anterior chamber volumes (ACV) were smaller in the LASIK group than in the control group. CONCLUSION: Our results demonstrated that the posterior corneal surface tends to show signs of central flattening and peripheral steepening 10 years after myopic LASIK surgery compared to that of non-operated myopic eyes.


Assuntos
Câmara Anterior/fisiopatologia , Endotélio Corneano/fisiopatologia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Adulto , Substância Própria/cirurgia , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia
11.
Invest Ophthalmol Vis Sci ; 57(8): 3821-7, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27438542

RESUMO

PURPOSE: To investigate tear film optical quality dynamics by analyzing the postblink temporal changes of objective scatter index (OSI). METHODS: A total of 109 myopic subjects without symptoms of dry eye and 32 myopic subjects diagnosed with dry eye disease were recruited in this cross-sectional study. The right eye for each subject was analyzed. Serial measurements of OSI were performed for 20 seconds in the interval of 0.5 second using a double-pass instrument, and 10 successive seconds of nonblinking immediately after a blink was selected to analyze the tear film optical quality dynamics. The tear breakup time (TBUT) was also measured. The mean OSI in 10 successive seconds and the correlation coefficient between OSI and time were analyzed. RESULTS: For subjects without symptoms of dry eye, 109 eyes were divided into two categories based on the correlation coefficient between OSI and time: category A (without positive correlation) and category B (with positive correlation). Categories A and B were further divided into four categories based on the mean OSI for 10 seconds: category A1 (36.7%, lower than 1.00); category A2 (33.0%, equal to or greater than 1.00); category B1 (13.8%, lower than 1.00), and category B2 (16.5%, equal to or greater than 1.00). Dry eye subjects were set as category C for comparison. There was no significant difference in the TBUT among the five categories (A1, A2, B1, B2, C) except between category C and category A1 (P < 0.01) and category C and category A2 (P < 0.05). CONCLUSIONS: Dynamic changes of OSI after blinking showed variations even in clinically asymptomatic subjects, and four categories of tear film were proposed based on the optical quality dynamics. The procedure using serial measurements of OSI as a noninvasive and objective method may have potential applications for detecting preclinical phase of dry eye disease in asymptomatic subjects.


Assuntos
Miopia/fisiopatologia , Fenômenos Ópticos , Lágrimas/fisiologia , Adolescente , Adulto , Piscadela/fisiologia , Estudos Transversais , Síndromes do Olho Seco/fisiopatologia , Desenho de Equipamento , Feminino , Humanos , Luz , Masculino , Óptica e Fotônica/instrumentação , Espalhamento de Radiação , Adulto Jovem
12.
PLoS One ; 10(2): e0117587, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25646846

RESUMO

PURPOSE: To evaluate the repeatability and reproducibility of a double-pass instrument (OQASII, Visiomereics SL, Spain), which objectively measures overall optical quality of the human eyes. METHODS: The right eye of 119 healthy subjects with best corrected visual acuity of 20/25 or better was included in this prospective, comparative, observational study. Two separate tests with OQASII were conducted sequentially on the same day by two different examiners. A week later, the first examiner conducted the third measurement. All subjects underwent three consecutive tests during each session. The repeatability and reproducibility of the modulation transfer function cut off frequency (MTF cutoff), the Strehl ratio, the OQAS values (OVs) at contrasts of 100%, 20% and 9%, and the objective scatter index (OSI) were analyzed. RESULTS: For MTF cutoff, Strehl ratio, OV100%, OV20%, OV9%, and OSI, the mean values were 39.32±9.75cpd, 0.22±0.06, 1.31±0.33, 1.33±0.39, 1.33±0.41, 0.60±0.42, respectively. Repeatability and reproducibility were good with a very low coefficient of variation and high interclass correlation coefficients (>0.88) for all parameters. Bland-Altman plots showed good correlation with 95% limits of agreement ranged from -6.04 to 6.78cpd, -0.05 to 0.05, -0.20 to 0.23, -0.29 to 0.32, -0.40 to 0.42, -0.23 to 0.21 in inter-observer, and -6.56 to 7.42cpd, -0.06 to 0.06, -0.22 to 0.24, -0.30 to 0.32, -0.35 to 0.34, -0.24 to 0.23 in inter-visit, respectively. CONCLUSION: The OQASII system yields excellent repeatability and good reproducibility for objective measurements of overall optical quality in clinic.


Assuntos
Testes Visuais/instrumentação , Visão Ocular , Adulto , Olho/patologia , Feminino , Humanos , Masculino , Dispositivos Ópticos , Estudos Prospectivos , Reprodutibilidade dos Testes , Espalhamento de Radiação , Adulto Jovem
14.
Chin Med Sci J ; 29(1): 33-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24698676

RESUMO

OBJECTIVE: To determine the efficacy of palliative radiotherapy in treating tumor-stage cutaneous T-cell lymphoma/mycosis fungoides (MF). METHODS: From January 2008 to January 2013, a total of 11 patients with tumor-stage MF were treated with local radiation therapy in Peking Union Medical College Hospital. The median age of these patients was 53.36 ± 14.45 years. Female-male ratio was 1:1.2. The average course of disease was 10.82 ± 3.37 years. All the patients were treated with local electronic beam irradiation with a total median dosage of 48.55 ± 9.51 (40-74) Gy in an average of 24.55 ± 5.57 (20-40) fractions, 5 fractions per week. RESULTS: The median follow-up time was 55.27 ± 29.3 (13-103) months. No severe acute or chronic side effects of irradiation were observed. Complete clinical response (CR) rate of the radiated sites was 54.5% (6/11), partial response (PR) rate was 36.4% (4/11), and the overall response rate (CR+PR) was 90.9%. One patient showed no response. CONCLUSION: Local radiotherapy with psolaren plus ultraviolet A and/or interferon maintaining treatment is an effective palliative therapy in the treatment of tumor-stage MF patients.


Assuntos
Micose Fungoide/radioterapia , Cuidados Paliativos/métodos , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Quimiorradioterapia Adjuvante/métodos , Intervalo Livre de Doença , Feminino , Humanos , Interferons/administração & dosagem , Interferons/uso terapêutico , Linfoma Cutâneo de Células T/tratamento farmacológico , Linfoma Cutâneo de Células T/patologia , Linfoma Cutâneo de Células T/radioterapia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/tratamento farmacológico , Micose Fungoide/patologia , Estadiamento de Neoplasias , Terapia PUVA/métodos , Dosagem Radioterapêutica , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Resultado do Tratamento
15.
Invest Ophthalmol Vis Sci ; 49(6): 2390-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18515581

RESUMO

PURPOSE: To compare the clinical outcome of on-flap and off-flap epi-LASIK for moderate to high myopia. METHODS: This prospective, observer-masked, randomized study included 62 eyes of 31 patients with myopia who underwent off-flap epi-LASIK (epikeratome; Moria, Antony, France) in one eye (off-flap group) and on-flap epi-LASIK in the contralateral eye (on-flap group). Corneal ablation was performed with a commercially available laser (Mel-80; Carl Zeiss Meditec, Oberkochen, Germany). Patients were seen at 3, 5, and 12 days and 1 and 3 months after surgery. Clinical outcomes were compared between groups. RESULTS: No significant between-group differences in the mean preoperative spherical equivalent (-6.18 +/- 1.29 D vs. -6.47 +/- 1.70 D), the change in lines of best corrected visual acuity at 3 months after surgery, and postoperative pain were found. Compared with the on-flap group, outcomes of better uncorrected visual acuity at 3 and 5 days after surgery (P < 0.001), rapider reepithelialization (P < 0.001), and lower level of haze at 1 and 3 months after surgery (P = 0.04, 0.04) were found in the off-flap group. Three months after surgery, contrast sensitivity function (CSF), with and without glare, did not differ from before surgery in both groups (P > 0.05) except CSF at 18 cpd with glare increased significantly in the off-flap group 3 months after surgery (P = 0.04). Wavefront aberration increased significantly from baseline in both groups 3 months after surgery (P < 0.05). The on-flap group revealed greater but insignificant increasing amplitude in wavefront aberration compared with the off-flap group. CONCLUSIONS: In comparison with on-flap epi-LASIK, off-flap epi-LASIK offers comparable postoperative pain, a lower level of haze formation, a rapider visual recovery, and better visual quality. Further investigations of a larger number of subjects and longer follow-up periods are warranted.


Assuntos
Córnea/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Retalhos Cirúrgicos , Adulto , Sensibilidades de Contraste/fisiologia , Método Duplo-Cego , Epitélio Corneano/fisiologia , Feminino , Humanos , Masculino , Dor Pós-Operatória , Estudos Prospectivos , Tonometria Ocular , Resultado do Tratamento , Acuidade Visual/fisiologia , Cicatrização/fisiologia
16.
Zhonghua Yan Ke Za Zhi ; 42(9): 782-7, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17173737

RESUMO

OBJECTIVE: To investigate the relationship between corneal astigmatism and second order wavefront aberration in myopic eyes. METHODS: The corneal astigmatism and the whole eye wavefront aberrations of both eyes of 246 subjects were measured using the Humphrey corneal topography and the WASCA wavefront analyzer. According to axial of the corneal astigmatism, the subjects were divided into five groups (WR(0), WR(180), AR, OA(45) and OA(135)). The corneal astigmatism was decomposed into J(45) and J(0) with a Vector-based method, and correlated with the 2nd order Zernike aberrations (C(3) and C(5)). RESULTS: The mean corneal astigmatisms for the five groups were -1.34 D x 6.87 degrees, -1.03 D x 23.15 degrees, -0.48 D x 89.55 degrees, -0.91 D x 156.87 degrees and -1.02 D x 176.74 degrees respectively. Most of the corneal J(45) and J(0) components were correlated significantly with the C(3) and the C(5) aberrations in the whole eye. While the correlation coefficients (R(2)) between the J(45) and the C(3) were 0.138, 0.119, 0.090, 0.526 and 0.501, the R(2) between the J(0) and the C(5) were 0.711, 0.736, 0.864, 0.866 and 0.785 for the five groups respectively. CONCLUSIONS: The corneal astigmatism plays an important role in determining the 2nd order wavefront aberration in the whole eye, and the combination processes between the corneal and internal astigmatism (compensation and/or addition) change with the axial of the corneal astigmatism.


Assuntos
Astigmatismo/fisiopatologia , Córnea/fisiopatologia , Topografia da Córnea/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Refração Ocular/fisiologia
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