M Test Research Articles

Image characteristics and quantitative analysis of multicolor imaging in eyes with cystoid macular edema

Objective To observe the imaging features of cystoid macular edema (CME) in multicolor imaging (MC), and to evaluate the value of MC in the diagnosis of CME. Methods Descriptive case series study. From August 2017 to June 2018, 42 eyes of 37 patients with CME diagnosed in the people's Hospital of Wuhan University were included in the study. Among them, there were 24 males and 13 females, with an average age of 48.51±10.29 years. There were 14 eyes with diabetic retinopathy, 14 eyes with central retinal vein occlusion, 8 eyes with branch retinal vein occlusion, 4 eyes with uveitis, and 2 eyes with Eales disease. The macular color fundus photography (CFP) was performed with Visucam 200 non-mydriatic fundus camera of Zeiss company in Germany. MC, frequnce domainoptical OCT (SD-OCT) and FFA were examined by Spectralis HRA2 + OCT of Heidelberg company in Germany. According to the MC standard method, five images, including 488 nm blue reflection (BR), 515 nm green reflection (GR), 820 nm infrared reflection (IR) imaging and standard MC and blue-green enhancement (BG), were obtained at the same time. Compared with SD-OCT, CFP and MC images were scored. Friedman M test and Wilcoxon signed rank test were used for statistical analysis. Results The standard MC and BG images showed blue-green uplift area or petal-shaped appearance, surrounded by green reflection areas with clear boundaries. BR image can be seen in the low reflexes area. On the GR image, there were patches or cystic low reflection areas, surrounded by a slightly high reflection. On the IR image, patches or cystoid high reflexes can be seen, surrounded by low reflection dark areas with clear boundaries. The average scores of CFP, standard MC, GB, IR, GR and BR were 1.20±0.94, 3.05±0.99, 2.90±1.04, 2.55±1.27, 2.00±0.94, 0.51±0.85 respectively, and the differences were statistically significant (χ2= 151.61, P=0.000). The score of CFP were significantly lower than that of standard MC (Z=-5.421), BG (Z=-5.354), IR (Z=-4.714), GR (Z=-4.438) and higher than that of BR (Z=-3.435). The differences were statistically significant (P=0.000, 0.000, 0.000, 0.000, 0.001). Conclusions The quality of MC imaging is better than that of CFP. Combined with SD-OCT, it can be used as an assistant method to diagnose CME. Key words: Macular edema/diagnosis; Tomographyoptical coherence; Fluorescein angiography; Multicolor imaging

Optimal adaptive statistical iterative reconstruction-V percentage in abdominal low dose enhanced CT of living liver transplantation infants

Objective To explore the optimal adaptive statistical iterative reconstruction-V (ASIR-V) percentage in abdominal low-dose enhanced CT in infants with living liver transplantation (LDLT). Methods Twenty consecutive infants (liver transplant candidates or patients after liver transplantation, body weight≤15.0 kg) were prospectively included as the test group in this study. All the infants underwent three-phase enhanced CT, hepatic artery, portal venous inflow and portal venous phase. Images were reconstructed with filtered back projection (FBP), 0, ASIR-V, 20% ASIR-V, 40% ASIR-V, 60% ASIR-V, 80% ASIR-V and 100% ASIR-V, respectively. The objective (noise SD, CT value of abdominal aorta, liver and spleen) and subjective (image quality score) analysis of image quality were conducted. The effective dose (ED) was also recorded. In order to test our conclusion, 10 infants with similar characteristics to test group were prospectively collected as validation group. The similar scanning protocol combined with the best ASIR-V were used. The image score and ED were recorded. One-way analysis of variance or Kruskal-Wallis H test were used to compare CT value, noise SD and image quality scores. Friedman M test was used to compare image quality score and independent-sample t test was used to compare ED between the test and validation group. Results CT value of all tissues derived from images reconstructed with different ASIR-V was similar in each phase (P>0.05). The noise SD had statistically significant differences among images reconstructed with different ASIR-V (P 0.05). The ED of the test group was (2.52±0.54) mSv, and significantly lower than that of validation group (1.49±0.18) mSv (P<0.05). Conclusion The best image quality can be obtained with forty percent ASIR-V whilethe radiation dose can be effectively reduced. Key words: Liver transplantation; Tomography,X-ray computed; Radiation dosage

Research on the different evaluation from the three parties of the clinical practice medical students' communication ability in OSCE

Objective To analyze the difference and correlation of the evaluation of the medical students' communication ability between the examiners, standardized patients (SP) and medical students themselves in objective structured clinical examination (OSCE), and to provide scientific basis for the appropriate evaluation method of medical students' communication ability. Methods OSCE was used to evaluate the communication ability of 90 medical students in Daping Hospital, Chongqing, and the three parties were evaluated by the examiners, SP and medical students themselves. Excel and SPSS 17.0 statistical analysis software were used, through Friendman M test, t test and correlation analysis to analyze the differences and correlation of the three parties evaluations. Results The different evaluation between the three parties on the communication ability of medical students was as follows. Examiner's evaluation was the lowest (8.39±1.18), SP's evaluation was the highest (9.62±0.73), Medical students themselves' evaluation was higher (9.28±1.09); The examiner's evaluation of Medical students' empathy, verbal communication ability, non-verbal communication ability and etiquette was lower (P=0.00). The correlation analysis of the three parties' evaluation showed that there was a significant correlation between the three parties on the communication ability, empathy and nonverbal communication ability (P<0.05). The evaluation of SP and medical students themselves on medical students' language communication ability and etiquette was significantly correlated (P<0.05). Conclusions Using examiner or SP or medical students themselves only to evaluate the communication ability of medical students is not accurate, The Examiner and SP as the main trial test personnel should collaborate to evaluate medical students' communication ability. The examiner can evaluate three projects such as what is medical ethics and law, empathy, nonverbal communication ability, while the SP can evaluate the two projects: what is language communication ability and etiquette. The collaborative evaluation of the two sides can be more accurate to reflect the doctor-patient communication ability of medical students. Key words: Objective structured clinical examination; Medical students; Communication ability; Evaluation method

Comparison of internal tumor volume based on different reconstruction modes of 4DCT for solitary pulmonary lesion

Objective To explore the influence of different reconstruction modes with time-weighted respiratory phases on the internal tumor volume (ITV) of solitary pulmonary lesion (SPL), and to evaluate the feasibilities of 8 and 4 equal time-weighted respiratory phases in 4DCT simulation. Methods 24 patients with SPL underwent 4D scanning. Images were reconstructed with 10, 8 and 4 equal time-weighted phases of the respiratory cycles, respectively. Gross tumor volumes (GTVs) were delineated on the three sets of reconstructed images and fused into ITVs, which were ITV10, ITV8 and ITV4 respectively. The differences of volumes, centroid of the ITVs and motions of GTV centroids in three-dimensional directions were compared. Statistical analysis was performed using the Friedman M test. Results The volumes of ITV10, ITV8 and ITV4 were (9.09±12.29) cm3, (9.10±12.47) cm3 and (8.98±12.61) cm3(P=0.001), respectively. There were no differences between the volumes of ITV10 and ITV8 after the Bonferroni correction (P=0.721), while the opposite between those of ITV10 and ITV4(P=0.002). The differences of centroid positions of ITV10, ITV8 and ITV4 in x-, y-and z-axes were all less than 1 mm ((12.22±7.71), (12.23±7.71), (12.22±7.71), Px=0.668); (43.30±29.38), (43.30±29.40), (43.31±29.39), Py=0.643; (5.66±3.67), (5.66±3.67), (5.66±3.67), Pz=0.878), similar to the motions of GTV centroids in three reconstructed modes ((0.69±0.56), (0.69±0.68), (0.79±0.51) mm, Px=0.356; (3.13±3.78), (3.13±4.05), (3.19±4.06) mm, Py=0.978; (1.18±1.31), (1.03±1.32), (1.16±1.34) mm, Pz=0.302). Conclusions There were no differences in volumes, centroid positions and motions between ITV10 and ITV8. The quantity of reconstruction images and GTV delineations according to 8 time-weighted phases were both less than conventional 10 phases. 8 time-weighted respiratory phases mode was feasible in 4DCT simulation for SPL. Key words: Tomography, X-ray computed, four-dimensional; Imaging reconstruction; Internal target volume; Lung neoplasms/radiotherapy

The Absolute and Uniform Convergence of Infinite Improper Integrals

(1988). The Absolute and Uniform Convergence of Infinite Improper Integrals. The American Mathematical Monthly: Vol. 95, No. 2, pp. 124-126.