Biomedical subjects

Montip Tiensuwan

Publications and source records attributed to Montip Tiensuwan.

8 recordsLinked to original sources

PubMed2006

Interobserver agreement in the interpretation of single-field digital fundus images for diabetic retinopathy screening.

PURPOSE: To assess agreement among a group of ophthalmic care providers, including ophthalmologists and trained nonphysician personnel, in the interpretation of single-field digital fundus images for diabetic retinopathy screening. DESIGN: Interobserver reliability study. PARTICIPANTS: Twelve ophthalmic care personnel, including 3 retina specialists, 3 general ophthalmologists, 3 ophthalmic nurses, and 3 ophthalmic photographers. METHODS: All participants were to read 400 good single-field digital fundus images of diabetic patients from a community hospital. The nonphysician personnel group read the images 1 month after attending a 2-day intensive instruction course regarding diabetic retinopathy screening. The ophthalmologists read the images without additional training. The 3 retina specialists read the images again together 2 months later to form a consensus regarding retinopathy severity and macular edema for each case. All readers used the Early Treatment Diabetic Retinopathy Study standard photographs as guidelines. MAIN OUTCOME MEASURES: The kappa statistic was used for the reliability assessment of the diabetic retinopathy severity and macular edema, and for the identification of cases that needed referral to ophthalmologists. RESULTS: There is only fair agreement among all readers. The multirater kappa coefficient for retinopathy severity is 0.34; for macular edema, 0.27; and for referral cases, 0.28. Retina specialists have the best agreement among all groups (kappa = 0.58 for retinopathy severity or macular edema, kappa = 0.63 for referrals). There is also fair agreement when all readers are compared with the consensus of retina specialists (kappas = 0.35, 0.28, and 0.29 for retinopathy severity, macular edema, and referrals, respectively), and the retina specialist group also has the best agreement (kappas = 0.63, 0.65, and 0.67 for retinopathy severity, macular edema, and referrals). CONCLUSIONS: Without additional training, retina specialists may be the most reliable personnel to interpret single-field digital fundus images for diabetic retinopathy screening. For other ophthalmic care personnel to achieve comparable reliability, a comprehensive instruction course with specific continuing education is essential. Authorized nonphysician interpreters should be experts, and new standard photographs for single-field digital fundus image interpretation may also be required to improve interobserver reliability.

Adult↗

PubMed2006

Normal internal organ weight of Thai adults correlated to body length and body weight.

OBJECTIVE: Examine the relationship between the internal organ weight with body weight and body length. MATERIAL AND METHOD: Analysis of data from 250 autopsies from the Ramathibodi Hospital from August 2003 to February 2005. The cases were from sudden unnatural death including accident, homicide and suicide and excluded decomposed bodies, fire related deaths and cases where medical treatment had been given. The age ranged from 15 to 88 years and there were 51 females and 199 males. Parson's correlation coefficient was used to examine the relationship between the internal organ weight with body weight and body length. RESULTS: The mean+/-standard deviation (SD) were represented by males and females respectively; Brain 1339+/-160/1165+/-184 gm, heart 311+/-66/278+/-160 gm, lung 910+/-347/675+/-255 gm, liver 1439+/-365/ 1214+/-275 gm, spleen 103+/-46/92.9+/-48 gm, kidney 260+/-68/230+/-42 gm. CONCLUSION: The relationship between internal organ weight and body weight showed each internal organ significantly correlated with body weight in males at p-value < 0.05, whereas in females it only correlated to liver, kidney and spleen at p-value < 0.05. For the correlation between internal organ weight and body length, it showed only brain, lung, liver and kidney correlated to the body length in males at p-value < 0. 05, but not in females.

Adolescent↗

PubMed2006

Relationship between bone and ash weight to age, body weight and body length of thai adults after cremation.

BACKGROUND: Cremation is the most common Thai funeral mode. In Thailand, there have not been any previous reports of bone and ash weight after cremation. OBJECTIVE: Collect the bone and ash weight after the cremation and find the variables that affected the bone and ash weight. MATERIAL AND METHOD: One hundred and ten samples, including fifty-five males and fifty-five females, were collected from the Thai population. A Thai crematorium (Series Tiger 1) that could produce a temperature of approximately 850 degrees C - 1200 degrees C was employed. It took about 1-1.5 hours to complete the incineration. RESULTS: The average bone and ash weight of the males was 2.68 kg with SD 1.41; female was 2.12 with SD 1.25; and total was 2.40 with SD 1.36. The present study supported that age and body weight affected the bone and ash weight while the body length (height) did not. The fitted equation was y = 1.969 - 0.01846 (age) + 0.03087 (body weight), where y = predicted bone and ash weight. CONCLUSION: The present study shows that age and body weight affected the bone and ash weight. From this information, the authors could find the predicted value of either age or body weight. If the authors would like to find the age, the authors can employ the fittest equation y = 76.097 - 3.219 (Bone and ash weight) where y = predicted age. Additionally, if the authors would like tofind the body weight, we can employ thefittest equation = 51.930 + 1.673 (Bone and ash weight) where y = predicted body weight.

Adolescent↗

PubMed2005

Water quality and breeding habitats of anopheline mosquito in northwestern Thailand.

Malaria transmission is dependent upon many hydrology-driven ecological factors that directly affect the vectorial competence, including the presence of suitable habitats for the development of anopheline larvae. Larval habitats were identified and characterized at three malaria endemic villages (Ban Khun Huay, Ban Pa Dae, and Ban Tham Seau) in Mae Sot district, Tak Province, in northwestern Thailand between July 2002 and June 2003. The Global Positioning System (GPS) was used to provide precise locational data for the spatial distribution of anopheline mosquito larvae and their habitats. Ten habitat categories were identified. Eighteen adult Anopheles species were identified from larvae in all the surveyed habitats. An. minimus was the most common species throughout the year. The relationship between eight abiotic variables (temperature, hardness, carbon dioxide, dissolved oxygen, nitrate, phosphate, silica and pH) and the abundance of four major species of malaria vectors (An. (Cel.) dirus, An. (Cel.) minimus, An. (Cel.) maculatus, and An. (Cel.) sawadwongporni), and six species of non-vectors (An. (Cel.) kochi, An. (Cel.) jamesii, An. (Ano.) peditaeniatus, An. (Ano.) barbirostris, An. (Ano.) campestris, and An (Cel.) vagus) larvae was investigated. The results from the multiple regression models suggest that hardness, water temperature and carbon dioxide are the best predictor variables associated with the abundance of An. minimus larvae (p < 0.001); water pH for An. dirus larvae (p < 0.001); temperature and pH for An. kochi larvae (p < 0.01); temperature and silica concentration for An. jamesii larvae (p < 0.001); dissolved oxygen and silica concentration for An. campestris larvae (p < 0.001); and pH and silica concentration for An. vagus larvae (p < 0.001). We could not identify key environmental variables for An. maculatus, An. sawadwongporni, An. peditaeniatus, and An. barbirostris.

Animals↗

PubMed2005

Screening for diabetic retinopathy in rural area using single-field, digital fundus images.

OBJECTIVE: To evaluate the practicability of using single-field, 2.3 million-pixel, digital fundus images for screening of diabetic retinopathy in rural areas. MATERIAL AND METHOD: All diabetic patients who regularly attended the diabetic clinic at Kabcheang Community Hospital, located at 15 kilometers from the Thailand-Cambodia border, were appointed to the hospital for a 3-day diabetic retinopathy screening programme. The fundi of all patients were captured in single-field, 45 degrees, 2.3 million-pixel images using nonmydriatic digital fundus camera and then sent to a reading center in Bangkok. The fundi were also examined through dilated pupils by a retinal specialist at this hospital. The grading of diabetic retinopathy from two methods was compared for an exact agreement. RESULTS: The average duration of single digital fundus image capture was 2 minutes. The average file size of each image was 750 kilobytes. The average duration of single image transmission to a reading center in Bangkok via satellite was 3 minutes; via a conventional telephone line was 8 minutes. Of all 150 patients, 130 were assessed for an agreement between dilated fundus examination and digital fundus images in diagnosis of diabetic retinopathy. The exact agreement was 0.87, the weighted kappa statistics was 0.74. The sensitivity of digital fundus images in detecting diabetic retinopathy was 80%, the specificity was 96%. For diabetic macular edema the exact agreement was 0.97, the weighted kappa was 0.43, the sensitivity was 43%, and the specificity was 100%. CONCLUSION: The image capture of the nonmydriatic digital fundus camera is suitable for screening of diabetic retinopathy and single-field digital fundus images are potentially acceptable tools for the screening. The real-time image transmission via telephone lines to remote reading center, however, may not be practical for routine diabetic retinopathy screening in rural areas.

Adult↗

PubMed2005

Application of log-linear models to cancer patients: a case study of data from the National Cancer Institute.

Cancer is a noninfectious disease which is on the increase throughout the world and has become a serious problem for public health in many countries, including Thailand. In Thailand, cancer has risen significantly to become a leading cause of death and most patients are admitted to the National Cancer Institute. The objective of this study is to identify the associated factors between personal, cancer/clinical variables of cancer patients using log-linear models. Tests of independence are used (chi-square and Cramer's V-value tests) to find out the relationships between any two variables. In addition two- and three-dimensional log-linear models are used to obtain estimated parameters and expected frequencies for these models. Amongst the models fitted, the best are chosen based on the analysis of deviance. The results of this study show that most paired variables of personal, cancer/clinical variables are significantly related at p-value <0.05. For both male and female patients, the variable site of the cancer is highly related to marital status, diagnostic evidence and treatment, which provide the highest Cramer's V value. Moreover, the site of cancer also affects the method of diagnostic evidence and treatment. Since the site of cancer in each sex is different, prevention for various sites of cancer should be considered for each specific sex. In addition, for male and female patients, treatment is related to the site of cancer. Consequently, physicians may consider these factors before selecting the appropriate method of treatment.

Epidemiologic Methods↗

PubMed2003

Repeatability of an automated Landolt C test, compared with the early treatment of diabetic retinopathy study (ETDRS) chart testing.

PURPOSE: To evaluate the repeatability of visual acuity scores from the automated test and compare them with the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. DESIGN: Instrument validation study based on a model of repeatability study in two observations. SMETHODS: a prospective, clinic-based, comparative study. A total of 206 participants without ocular diseases and refractive errors in their right eyes were randomly enrolled in the automated group in which 107 participants performed the automated test and the ETDRS group in which 99 participants read the ETDRS chart. All participants were tested with only their right eyes without corrections at 4 meters and came back to have the same tests 1 week later. The automated test used the Landolt rings as optotypes and was conducted by a low-ended personal computer with a 15-inch monitor and a wireless keyboard. The "letter" score calculated by counting every correct response to optotypes, and the "threshold curve" score interpreted from the optotype size at the midpoint of a visual acuity threshold curve. RESULTS: The 95% confidence interval of test-retest of visual acuity scores from the automated test are comparable to the ETDRS chart (.143 compared with.125 for letter scores,.145 compared with.122 for threshold curve scores). The score repeatabilities, calculated from the standard deviations of test-retest, from the automated test are also comparable to the ETDRS chart (.201 compared with.177 for letter scores,.206 compared with.172 for threshold curve scores). All comparisons demonstrated no statistical difference (P >.05). CONCLUSIONS: The automated testing system in this study enables practical measuring visual acuity by the Landolt rings. The system's repeatability, which is comparable to the ETDRS chart, supports its role as an alternative tool for measuring outcome in new clinical research. Its ability to practically generate visual acuity threshold curves may also be useful in future clinical research studies.

Adolescent↗

PubMed2002

The Thai logarithmic visual acuity chart.

OBJECTIVE: To evaluate visual acuity scores from the Thai and the standard logarithmic visual acuity chart. DESIGN: Comparative non-randomized clinical study. PARTICIPANTS AND METHOD: 153 subjects, calculated from sample size estimation, without any ocular disease and aged between 18 and 80 years old who could read English and at least 3 out of 5 letters of the largest line of both charts were enrolled to use only their right eyes to read the Thai and the standard logarithmic visual acuity chart without any refractive correction. 27 subjects came back for second measurements of visual acuity in the same manner as the first a week later. MAIN OUTCOME MEASUREMENT: The visual acuity scores were divided into the Snellen or the whole line score and the ETDRS or the letter-by-letter score. The former was compared by weighted Kappa and the latter was compared by the paired t-test. RESULTS: There was high agreement in weighted Kappa between the Snellen scores from the Thai and standard chart (k = 0.7375). There was also high agreement in weighted Kappa between the Snellen scores from the first and second reading of the Thai chart (k = 0.7304) and the standard chart (k = 0.7282). A high correlation was observed between the ETDRS scores from the Thai and standard charts (r = 0.947). Also there was a high correlation between the ETDRS scores of the first and second reading of both the Thai chart (r = 0.962) and the standard chart (r = 0.952). There was a significant difference between the ETDRS scores from the Thai and standard chart (p<0.0001). There was no significant difference between the ETDRS scores from the first and second reading of either the Thai chart (p = 0.794) or the standard chart (p = 0.62). CONCLUSION: The Snellen visual acuity score from the Thai chart is comparable to the standard chart. Although the ETDRS score from the Thai chart is different statistically from the standard chart, its test-retest variability tends to be low. This suggests the possibility of using the Thai chart for monitoring of the ETDRS score in research studies.

Adolescent↗