Research progress on the stress-strain index of Corvis ST / 国际眼科杂志(Guoji Yanke Zazhi)

Corneal visualization Scheimpflug technology(Corvis ST)is currently the most commonly used clinical device for assessing in vivo corneal biomechanics. The new parameter stress-strain index(SSI)has been a hot topic of clinical research in recent years, which not only directly reflect corneal biomaterial stiffness, but also closely correlates with the progression of certain diseases. SSI was generated based on the predictions of corneal behavior using finite element(FE)numerical modeling to simulate the effects of intraocular pressure and Corvis ST jets. The SSI algorithm does not change with central corneal thickness(CCT), intraocular pressure, or biomechanically corrected intraocular pressure(BIOP), but it is clearly associated with altered collagen fibres in the corneosclera. The principles of SSI, the relationship between age and SSI, the relationship between axial length and SSI, the relationship between myopia and SSI, and the application of SSI are summarized and concluded.

Age-related variations in corneal stress-strain index in the Indian population

Purpose: To report age?related variations in corneal stress–strain index (SSI) in healthy Indians. Methods: It was a retrospective study where healthy Indian individuals aged between 11 and 70 years who had undergone corneal biomechanics assessment using Corvis ST between January 2017 and December 2021 were enrolled. Composite corneal biomechanical parameters and corneal SSI were abstracted from Corvis ST and compared across different age groups using one?way analysis of variance (ANOVA). Also, Pearson’s correlation was used to evaluate the association between age and SSI. Results: Nine hundred and thirty?six eyes of 936 patients with ages between 11 and 77 years with mean ± SD intraocular pressure (IOP) and pachymetry of 16.52 ± 2.10 mmHg and 541.13 ± 26.39 ?s, respectively. Composite corneal biomechanical parameters such as deformation amplitude ratio max at 1 mm (P < 0.001) and 2 mm (P < 0.001), biomechanically corrected IOP (P = 0.004), stiffness parameter at A1 (P < 0.001, Corvis biomechanical index (P < 0.018), and SSI (P < 0.001) were found to be significantly different as a function of age group. We noted a statistically significant positive association of SSI with age (P < 0.001), spherical equivalent refractive error (P < 0.001), and IOP (P < 0.001) and a significant negative association with anterior corneal astigmatism (P < 0.001) and Anterior chamber depth (ACD) (P < 0.001). Also, SSI was positively associated with SPA1 and bIOP, whereas negatively associated with integrated radius, max inverse radius, and Max Deformation amplitude (DA) ratio at 1 mm and 2 mm. Conclusion: We noted a positive association of corneal SSI with age in normal healthy Indian eyes. This information could be helpful for future corneal biomechanical research.

Characteristics of new corneal biomechanical parameters in different degrees of myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To study the characteristics of new corneal biomechanical parameters in different degrees of myopia and analyze the correlation of the new parameter stress-strain index(SSI).METHODS: A cross-sectional study was conducted on 366 adult patients(718 eyes)with different degrees of myopia who received treatment at the First Affiliated Hospital of Dali University from October 2021 to November 2021, aged 18-50 years, and the spherical equivalent(SE)was -0.50～-16.75D. The axial length(AL)of the eye was measured by IOL master, and the new corneal biomechanical parameters, central corneal thickness(CCT)and intraocular pressure(IOP)were measured by corneal visualization Scheimpflug technology(Corvis ST). The subjects were categorized into low myopia, moderate myopia and high myopia groups according to SE. The data were analyzed by ANOVA and Pearson correlation.RESULTS: The ratio of the thinnest corneal thickness to horizontal thickness change rate(ARTh)and SSI were statistically significant(P&#x0026;#x003C;0.001), while the remaining parameters were not statistically significant(P&#x0026;#x003E;0.05). SSI was positively correlated with age(r=0.102, P=0.006), SE(r=0.361, P&#x0026;#x003C;0.001), IOP(r=0.175, P&#x0026;#x003C;0.001), CCT(r=0.098, P=0.009), SPA1(r=0.182, P&#x0026;#x003C;0.001), negatively correlated with AL(r=-0.331, P&#x0026;#x003C;0.001), IR(r=-0.545, P&#x0026;#x003C;0.001)and had no correlation with other corneal biomechanical parameters(P&#x0026;#x003E;0.05).CONCLUSION: With the increase of myopia degree and the elongation of the axial length, the SSI value becomes smaller and the corneal hardness decreases. SSI may be a helpful corneal biomechanical indicator for future research on myopia.

Value of prostate biopsy guided by transrectal real-time ultrasonic elastography combined with peak strain index in the diagnosis of prostate cancer / 肿瘤研究与临床

Objective:To investigate the value of prostate biopsy guided by transrectal real-time ultrasonic elastography (TRTE) combined with peak strain index (PSI) in the diagnosis of prostate cancer and the correlation with TRTE score and pathological Gleason score.Methods:A total of 80 patients with suspected prostate cancer who underwent TRTE in the First Affiliated Hospital of Hebei North University from January 2019 to December 2019 were selected. The PSI for suspicious lesions was measured, and targeted puncture biopsy guided by TRTE combined with PSI was performed on the patients, and then followed by systematic puncture biopsy. The outcomes of targeted biopsy and systematic biopsy were analyzed. Taking pathological biopsy results as the gold standard, the detection rates of prostate cancer and benign prostate lesions detected by both biopsies methods were compared; the prostate volume, serum prostate specific antigen (PSA) level and PSI were compared between patients with prostate cancer and benign prostatic lesions. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to determine the best cut-off value of PSI in the diagnosis of prostate cancer. The values of conventional ultrasound versus TRTE combined with PSI in the diagnosis of prostate cancer were assessed. The positive rate of biopsy puncture points under the guidance of TRTE combined with PSI was compared with that of systematic biopsy. The correlation between TRTE score and pathological Gleason score of prostate malignant lesions was analyzed.Results:Among 80 patients, 45 patients (56.25%) were diagnosed as prostate cancer by prostate puncture biopsy, and 35 patients (43.75%) were benign prostate lesions. Among 45 patients with prostate cancer, 42 cases (93.33%) of prostate cancer were detected by using TRTE combined with PSI-guided targeted puncture biopsy, and 38 cases (84.44%) of prostate cancer were detected by using systematic puncture biopsy; there was no significant difference in the detection rate of prostate cancer by both biopsies methods ( χ2 = 1.80, P = 0.180). The level of serum PSA and PSI value in the prostate cancer group were higher than those in the benign prostate lesion group, and the difference was statistically significant ( t value was 65.28 and 14.93, all P < 0.05). The clinical value of PSI value in the diagnosis of prostate cancer was analyzed by using ROC curve. The results showed that the AUC was 0.857 (95% CI 0.772-0.941), and the optimal cut-off value of PSI was 5.68; PSI ≥ 5.68 was treated as the malignant cancer and PSI < 5.68 was treated as the benign cancer. The sensitivity, specificity and accuracy of TRTE combined with PSI in the diagnosis of prostate cancer were 91.11%, 94.29%, and 92.50%, respectively, which were higher than those of conventional ultrasound (73.33%, 68.57% and 71.25%), and the differences were statistically significant (all P < 0.05). A total of 89 suspected lesions were detected in 80 patients through TRTE combined with PSI, and each suspected lesion was detected by using 2-needle targeted puncture biopsy. There were 178 needles in total including 88 needles of prostate cancer and the positive rate of puncture points was 49.44% (88/178); there were 800 needles in total detected by using 10-needle systematic puncture biopsy including 203 needles of prostate cancer and the positive rate of puncture points was 25.38% (203/800); the positive rate of puncture points guided by TRTE combined with PSI puncture biopsy was higher than that by systematic puncture biopsy, and the difference was statistically significant ( χ2 = 40.337, P < 0.05). For prostate malignant lesions, the Spearman correlation analysis showed that TRTE score was positively correlated with pathological Gleason score ( r = 0.618, P < 0.05). Conclusion:TRTE combined with PSI-guided targeted puncture biopsy plays an important role in the diagnosis of prostate cancer, and it can effectively improve the positive rate of puncture points.

Expression analysis of myocardial strain index after repair of abnormal origin of left coronary artery of pulmonary artery in children / 中华胸心血管外科杂志

Objective:To study the expression characteristics of myocardial strain index after the abnormal origin of the left coronary artery of the pulmonary artery in children was repaired.Methods:The data of 30 children (study group) with abnormal origin of pulmonary artery left coronary artery repair from August 2017 to August 2021 were analyzed. In addition, healthy children during the same period were selected as the control group, and the study group was compared before and after treatment and the control group. Circumferential and radial peak myocardial strain index, post-contraction strain index.Results:The longitudinal, circumferential, and radial overall peak strain indexes of the study group before and after treatment were significantly lower than those of the control group, and the longitudinal, circumferential, and radial overall peak strain indexes of the study group after treatment were significantly higher than those before treatment ( P<0.05); The longitudinal, circumferential, and radial peak strain indexes of the study group before treatment were significantly lower than those of the control group. After treatment in the study group, the middle section of the longitudinal inferior wall, the middle section of the anterior wall, the basal section of the anterior wall, the apex, and the circumferential direction were significantly lower The peak strain index of the basal segment of the inferior wall and the middle segment of the inferior wall was significantly lower than that of the control group; and the longitudinal, circumferential, and radial peak strain indexes of the study group after treatment were significantly higher than those before treatment ( P<0.05); the study group children before treatment Longitudinal, circumferential, and radial PSI indexes were significantly lower than those of the control group. After treatment, the study group was treated in the longitudinal inferior wall, septal apical segment, circumferential inferior wall basal segment, inferior wall middle segment, and radial PSI anterior wall basal segment, apex. The part was significantly higher than that of the control group; and the longitudinal, circumferential, and radial PSI of the study group after treatment were significantly lower than before treatment ( P<0.05). Conclusion:After ALCAPA repair, the overall and regional strain and overall synchronization are improved, indicating that the resting myocardium has recovered, but the strain of certain segments supplied by the abnormal left coronary artery fails to normalize after ALCAPA repair. Persistent myocardial injury is consistent, which can provide some guidance for the prognosis assessment of children with ALCAPA.

Use of strain ultrasound elastography versus fine-needle aspiration cytology for the differential diagnosis of thyroid nodules: a retrospective analysis

OBJECTIVE: Fine-needle aspiration cytology is the risk stratification tool for thyroid nodules, and ultrasound elastography is not routinely used for the differential diagnosis of thyroid cancer. The current study aimed to compare the diagnostic parameters of ultrasound elastography and fine-needle aspiration cytology, using surgical pathology as the reference standard. METHODS: In total, 205 patients with abnormal thyroid function test results underwent ultrasound-guided fine-needle aspiration cytology on the basis of the American College of Radiology Thyroid Imaging-Reporting and Data System classification and strain ultrasound elastography according to the ASTERIA criteria. Histopathological examination of the surgical specimens was performed according to the 2017 World Health Organization classification system. Moreover, a beneficial score analysis for each modality was conducted. RESULTS: Of 265 nodules, 212 measured ≥1 cm. The strain index value increased from benign to malignant nodules, and the presence of autoimmune thyroid diseases did not affect the results (p>0.05 for all categories). The sensitivities of histopathological examination, ultrasound elastography, and fine-needle aspiration cytology for detection of nodules measuring ≥1 cm were 1, 1, and 0.97, respectively. The working area for detecting nodule(s) in a single image was similar between strain ultrasound elastography and fine-needle aspiration cytology for highly and moderately suspicious nodules. However, for mildly suspicious, unsuspicious, and benign nodules, the working area for detecting nodule(s) in a single image was higher in strain ultrasound elastography than in fine-needle aspiration cytology. CONCLUSION: Strain ultrasound elastography for highly and moderately suspicious nodules facilitated the detection of mildly suspicious, unsuspicious, and benign nodules.

A case of extensor pollicis longus (EPL) tendon rupture in an automotive assembly line worker: an ergonomic evaluation through job strain index (JSI) and musculoskeletal risk factor survey

BACKGROUND: We report a case of extensor pollicis longus (EPL) tendon rupture caused by repetitive motions and awkward posture on hand and wrist joints. CASE PRESENTATION: A 47-year-old right-handed man who worked for 15 years in an assembly line at an automotive manufacturing company has been diagnosed with a complete tear of right EPL tendon. We investigated the patient's occupational history in detail and evaluated the tasks ergonomically through musculoskeletal risk factors survey and job strain index (JSI) using the 22 task-related videos recorded by the patient. Three out of the 12 tasks (25%) were identified as high-risk work on the hand and wrist in the musculoskeletal risk factors survey in 2016. Among the 22 tasks analyzed by JSI, 11 tasks (50%) were evaluated as probably hazardous. In addition, he used localized vibration tools in 19 (86.4%) out of 22 tasks. CONCLUSION: We concluded the patient's disease was probably caused by repetitive motion and improper posture of the hand and wrist, and the hand-arm vibration is a possible cause as well.

Impact of transrectal real-time tissue elastography guiding biopsy combined with peak strain index for diagnosing prostate cancer / 中华泌尿外科杂志

Objective To evaluate the value of transrectal real-time tissue elastography (RTE) targeted prostate biopsy in the peripheral zone combined with peak strain index.Methods One hundred and forty-one patients with suspicious prostate lesions in the peripheral zone were evaluated from February 2011 to February 2014.All the patients underwent RTE with a mean age of 71.6 years,PSA of 30 ng/ml,prostate volume of 50.3 ml and measured peak strain index (PSI).The diagnostic value of PSI was assessed by receiver operating characteristic (ROC) curve.Two-core RTE combined with PSI targeted prostate biopsy was taken and subsequently a 10-core systematic biopsy was taken.The value of RTE was evaluated.The data of targeted biopsy and systematic biopsy in prostate were both reviewed and statistically compared.Results Cancer was detected in 72 of 141 patients (PSI,mean 24.79),and 69 patients had benign prostate disease (PSI,mean 3.02).PSI value of prostate cancer was significantly higher than that of the benign lesions (P ＜ 0.05).Prostate cancer could be predicted with the highest sensitivity (87.5％) and specificity (88.6％) using the cutoff value of PSI ≥ 5.97 with an area under the curve of 0.95.RTE targeted biopsy combined with PSI could detect 95.6％ of moderate or high risk prostate cancer.One hundred and fifty-nine suspicious areas detected by RTE in 141 patients were biopsied with 2 cores for each area.The positive incidence of prostate cancer in RTE-targeted biopsy cores was 44％ and in systematic biopsy was 30.2％ (P ＜ 0.05).Among the 72 prostate cancer patients,63 cases (87.5％) were detected by RTE-targeted biopsy,62 cases (86.1％) by systematic biopsy (P ＞ 0.05).Conclusions RTE combined PSI can improve the detection rate of prostate cancer in the peripheral zone and likewise guide targeted biopsy combined with svstematic biopsy to detect more moderate or high risk prostate cancer.

Effect of Ibandronate and hPTH on the Viscoelastic Response of Ovariectomized Rat Femur / 대한골다공증학회지

PTH and ibandronate are proven to be effective in reversing negative effects of postmenopausal osteoporosis in terms of bone architecture and density. However, the changes of viscoelastic properties of the bone during the pathogenesis of osteoporosis and its treatment were seldom studied. Thus, this study aimed at studying the viscoelastic changes in PTH and ibandronate treated ovariectomized rat to assess the efficacy of the treatments. In this study, distal femurs of twenty-two female rats from four different groups (SHM, OVX, PTH and IBN) were evaluated using CT, pQCT and nanoindentation tests. While density parameters were well preserved in ibandronate treated group, elastic modulus and hardness were found to be better in PTH treated group. Thus, cortical and trabecular bone could be differentially affected by these two categories of drug, due to their difference in the action of mechanism. Moreover, viscosity of the cortical bone showed a positive correlation (R(2)=0.72) with bone strength predictor SSIy, which would possibly correlate with fracture risk.

LER/DORT: que métodos de avaliação do risco? / WRULMSDs: selection of risk assessment methods

O processo de seleção dos métodos observacionais de avaliação do risco de LER/DORT é complexo, mas fundamental para a gestão do risco. Em Setúbal, no período de 2004 a 2005, numa empresa portuguesa da indústria automobilística, onde a avaliação do risco foi previamente efetuada, reaplicou-se o método OCRA checklist (avaliação do risco de LER/DORT ao nível dos membros superiores) em postos de trabalho (n=152) montagem final e pintura classificados de risco moderado/elevado (OCRA ?16,5). Nas situações em que se reconfirmou a presença de risco (n=71), aplicaram-se três outros métodos: RULA, SI e HAL. Registraram-se sequências em vídeo da atividade de trabalho para avaliar a validade preditiva dos métodos. Revelam-se divergências entre os métodos na classificação dos postos de trabalho de risco elevado: OCRA 34 postos; HAL 35 postos; SI 31 postos; RULA 7 postos. A análise do efeito de cada variável independente (fator de risco) nos scores finais dos métodos (regressão linear multivariada) revela distintos contributos e processos de ponderação/avaliação do risco de LER/DORT. A análise dos registros em vídeo evidencia diversas validades preditivas relativamente aos fatores de risco integrantes dos métodos aplicados. Os resultados indicam a necessidade de uma seleção do método de avaliação do risco de LER/DORT adequada a cada situação (real) de trabalho, baseada no maior conhecimento dos métodos.

The process for selecting observational methods for evaluating work-related upper limb musucloskeletal disorders (WRULMSDs) is complex, but essential to risk management. In a Portuguese automotive industry plant (Setúbal, 2004-05), where all jobs had been previously analyzed, OCRA checklist was reapplied (final assembling and painting) in workstations (n=152) classified as moderate/ high risk (score 16.5 OCRA). In all risk confirmed cases (n=71) three other methods were applied: RULA, SI, and HAL. Sequences of working activities were recorded on video to estimate the predictive validity of the methods. The results show differences in the final scores of the methods in the same workstations: OCRA reveals 34 workplaces with high risk; SI only ranked 31 positions with high risk; HAL has 35 high risk workplaces, and RULA only 7. Analysis of the effect of each independent variable (risk factor) in the final scores of the methods, based on linear regression analysis, reveals different contributions and, consequently, different ways of assessing WRULMSD risk. The video analysis also highlights different predictive validities for the risk factors in each method. These results indicate the need to select the appropriate WRULMSD risk assessment instrument adequate to each real work situation.