Visual, ocular surface, and extraocular diagnostic criteria for determining the prevalence of computer vision syndrome: a cross-sectional smart-survey-based study

Background: The American Optometric Association defines computer vision syndrome (CVS), also known as digital eye strain, as “a group of eye- and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use”. We aimed to create a well-structured, valid, and reliable questionnaire to determine the prevalence of CVS, and to analyze the visual, ocular surface, and extraocular sequelae of CVS using a novel and smart self-assessment questionnaire.   Methods: This multicenter, observational, cross-sectional, descriptive, survey-based, online study included 6853 complete online responses of medical students from 15 universities. All participants responded to the updated, online, fourth version of the CVS questionnaire (CVS-F4), which has high validity and reliability. CVS was diagnosed according to five basic diagnostic criteria (5DC) derived from the CVS-F4. Respondents who fulfilled the 5DC were considered CVS cases. The 5DC were then converted into a novel five-question self-assessment questionnaire designated as the CVS-Smart.   Results: Of 10000 invited medical students, 8006 responded to the CVS-F4 survey (80% response rate), while 6853 of the 8006 respondents provided complete online responses (85.6% completion rate). The overall CVS prevalence was 58.78% (n = 4028) among the study respondents; CVS prevalence was higher among women (65.87%) than among men (48.06%). Within the CVS group, the most common visual, ocular surface, and extraocular complaints were eye strain, dry eye, and neck/shoulder/back pain in 74.50% (n = 3001), 58.27% (n = 2347), and 80.52% (n = 3244) of CVS cases, respectively. Notably, 75.92% (3058/4028) of CVS cases were involved in the Mandated Computer System Use Program. Multivariate logistic regression analysis revealed that the two most statistically significant diagnostic criteria of the 5DC were greater than or equal to 2 symptoms/attacks per month over the last 12 months (odds ratio [OR] = 204177.2; P <0.0001) and symptoms/attacks associated with screen use (OR = 16047.34; P <0.0001). The CVS-Smart demonstrated a Cronbach’s alpha reliability coefficient of 0.860, Guttman split-half coefficient of 0.805, with perfect content and construct validity. A CVS-Smart score of 7–10 points indicated the presence of CVS.   Conclusions: The visual, ocular surface, and extraocular diagnostic criteria for CVS constituted the basic components of CVS-Smart. CVS-Smart is a novel, valid, reliable, subjective instrument for determining CVS diagnosis and prevalence and may provide a tool for rapid periodic assessment and prognostication. Individuals with positive CVS-Smart results should consider modifying their lifestyles and screen styles and seeking the help of ophthalmologists and/or optometrists. Higher institutional authorities should consider revising the Mandated Computer System Use Program to avoid the long-term consequences of CVS among university students. Further research must compare CVS-Smart with other available metrics for CVS, such as the CVS questionnaire, to determine its test-retest reliability and to justify its widespread use

Development of an efficient CFD-based procedure with transitionsensitive turbulence model for evaluating the performance of marine propellers

In this paper, a CFD-based procedure for the evaluation of the performance characteristics of the well-known PPTC propeller, at model scale, is presented in detail. Results are obtained using one of the Local Correlation based Transition Models (LCTM), namely, the −̃ transition model in combination with the − SST turbulence model in a RANS-based numerical procedure to predict transition over the blade surface. The aim of using the − ̃ transition model is to predict the onset of transition and its influence on the propeller’s overall performance and on the flow behavior. Another aim of the work is to investigate the influence of the laminar-turbulent transition on the propeller’s flow. With the transition model, the constrained streamlines reflect an improvement in the flow pattern as compared to that of the model used for fully turbulent flow. Results also show an accurate prediction of the propeller’s global coefficients when the transition model is applied. Finally, a comparison between the results of the different transition models is conducted showing privilege of the −̃ over other transition models in terms of predicting the overall performance of the propeller

Open reduction internal fixation versus external fixation with limited internal fixation for displaced comminuted closed pilon fractures: A randomised prospective study

Background: Pilon fractures involve the dome of the distal tibial articular surface. The optimal treatment for high-energy pilon fractures remains controversial. Some authors advocate the use of open reduction and internal fixation (ORIF) to avoid articular incongruence. Others advocate the use of bridging external fixation with limited internal fixation (EFLIF) to reduce soft tissue complications. Literature reports of prospective studies comparing the radioclinical outcomes of ORIF and EFLIF in high-energy fractures are scarce. Retrospective studies have their limitations because of insufficient randomisation. The objective of this randomised prospective study is to compare the clinical, radiologic and functional outcomes of displaced and comminuted closed pilon fractures, Rüedi and Allgöwer type II and III, treated by either ORIF or EFLIF. Materials and methods: Forty-two patients were selected for the study. Twenty-two patients were subjected to ORIF and 20 patients were subjected to EFLIF. We used the American Orthopaedic Foot and Ankle Society score as a standard method of reporting clinical status of the ankle. Patients were followed-up clinically and radiologically for over 2 years after the surgical treatment. Results: The results of ORIF and EFLIF in treatment of high-energy pilon fractures are equally effective in terms of functional outcomes and complication rates on the short term. Conclusion: Soft tissue integrity and fracture comminution seem to have a significant influence on outcomes of intervention. A prospective multicentre study with a larger sample size that controls for other associated variables and comorbidities is warranted. Level of evidence: Level II. 中文摘要: 背景: Pilon骨折涉及脛骨遠端關節面的圓頂。高能量Pilon骨折的最佳治療方法仍然存在爭議。 一些作者主張使用開放復位和內固定(ORIF)來避免關節不一致。 其他作者主張用橋接外固定和有限內固定(EFLIF)來減少軟組織並發症。 比較ORIF和EFLIF在高能量骨折中的放射臨床結局的前瞻性研究的文獻報導很少。 回顧性研究由於隨機化不足而有其局限性。 這項隨機前瞻性研究的目的是比較以ORIF或EFLIF治療移位的粉碎性閉合Pilon骨折Rüedi和Allgöwer II型和III型的臨床、放射學和功能結果。 材料與方法: 選擇42例患者進行研究。 二十二名患者接受了ORIF, 二十名患者接受了EFLIF。 我們使用美國骨科腳踝學會(AOFAS)評分作為報告踝關節臨床狀態的標準方法。 患者的臨床和放射學隨訪超過手術治療後兩年。 結果: ORIF和EFLIF治療高能量Pilon骨折的療效在短期內功能結局和並發症發生率方面同樣有效。 結論: 軟組織完整性和骨折粉碎似乎對手術結果有顯著影響。 具有較大樣本量的前瞻性多中心研究以控制其他相關變量和合併症是有必要的。 Keywords: external fixation, internal fixation, intraarticular ankle fractures, prospective, tibial plafon

Ultrasound-guided serratus anterior plane block versus thoracic paravertebral block for perioperative analgesia in thoracotomy

Background: Thoracotomy needs adequate powerful postoperative analgesia. This study aims to compare the safety and efficacy of ultrasound (US)-guided serratus anterior plane block (SAPB) and thoracic paravertebral block (TPVB) for perioperative analgesia in cancer patients having lung lobectomy. Patients and Methods: This clinical trial involved 90 patients with lung cancer scheduled for lung lobectomy randomly divided into three groups according to the type of preemptive regional block. Group TPVB received US-guided TPVB. In Group SAPB, US-guided SAPB was performed. The patients of the control Group received general anesthesia alone. The outcome measures were postoperative visual analog scale (VAS) score, intraoperative fentanyl consumption, time of first rescue analgesic, total dose postoperative analgesic, and drug-related adverse effects. Results: Analgesia was adequate in TPVB and SAPB groups up to 24 h. VAS score was comparable in TPVB and SAPB groups and significantly lower compared to control group up to 9 h postoperatively. At 12 and 24 h, TPVB group had significantly lower VAS score relative to SAPB and control groups. Total intraoperative fentanyl consumption was significantly lower in TPVB and SAPB Groups compared to control group. The majority of TPVB Group cases did not need rescue morphine, while the majority of control group needed two doses (P < 0.001). The hemodynamic variables were stable in all patients. Few cases reported trivial adverse effects. Conclusion: Preemptive TPVB and SAPB provide comparable levels of adequate analgesia for the first 24 h after thoracotomy. TPVB provided better analgesia after 12 h. The two procedures reduce intraoperative fentanyl and postoperative morphine consumption