The application of the spot the difference teaching method in clinical skills training for residents.

BACKGROUND: Clinical skill training (CST) is indispensable for first-year surgical residents. It can usually be carried out through video-based flipped learning (FL) within a web-based learning environment. However, we found that residents lack the process of reflection, blindly imitating results in losing interest and passion for learning in the traditional teaching pattern. The teaching method of "spot the difference" (SDTM), which is based on the fundamentals of the popular game of "spot the difference," is designed to improve students' participation and reflective learning during skill training. This study aimed to evaluate this novel educational model's short-term and long-term effectiveness for surgical residents in China. METHODS: First-year residents who required a three-month rotation in the head and neck surgery department were recruited to participate in a series of CSTs. They were randomized into SDTM and traditional FL (control) groups. Clinical skill performance was assessed with validated clinical skill scoring criteria. Evaluations were conducted by comparing the scores that contain departmental rotation skill examinations and the first China medical licensing examination (CMLE) performance on practical skills. In addition, two-way subjective evaluations were also implemented as a reference for the training results. Training effects were assessed using t tests, Mann-Whitney-Wilcoxon tests, chi-square tests, and Cohen' s effect size (d). The Cohen' s d value was considered to be small (<0.2), medium (0.2-0.8), or large (>0.8). RESULTS: The SDTM group was significantly superior to the control group in terms of after-department skill examination (t=2.179, p<0.05, d=0.5), taking medical history (t=2.665, p<0.05, d=0.59), and CMLE performance on practical skill (t=2.103, p<0.05, d=0.47). The SDTM members rated the curriculum more highly than the control on the items relating to interestingness and participation (p < 0.05) with large effect sizes (d >0.8). There were no significant differences between the two groups on clinical competence (t=0.819, p=0.415, d=0.18), the first-time pass rate for CMLE (χ2 =1.663, p=0.197, d=0.29), and short-term operational skills improvement (t=1.747, p=0.084, d=0.39). CONCLUSIONS: SDTM may be an effective method for enhancing residents' clinical skills, and the effect is significant both short- and long-term. The improvement effect seemed to be more significant in the peer-involved SDTM than training alone. However, despite positive objective results, SDTM still risks student learning burnout. TRIAL REGISTRATION: ISRCTN registry, ISRCTN10598469 , 02/04/2022，retrospectively registered.

[Clinical Study on the Correlation Between Tinnitus and Hearing Loss in 400 Patients].

OBJECTIVE: To investigate the correlation between tinnitus and hearing loss. METHODS: Clinical data of 400 patients presented with tinnitus as the first chief complain were analyzed. The relationship between tinnitus and hearing loss was categorized based on sites,onset time of tinnitus and hearing loss,for the purpose of provideing clinical evidence to explore the etiology,treatment and prognosis of tinnitus. RESULTS: Among the 400 patients,61% of them did not show the correlation of tinnitus with hearing loss (52.05% with normal hearing,and 47.95% with hearing loss),while only 39% had the relationship (70.51% related,29.49% possibly related). CONCLUSION: In this study,no absolute correlation between tinnitus and hearing loss was observed. Tinnitus and hearing loss may not be treated in the same way.

Case presentation of an intranasal ectopic tooth in a pediatric patient.

An ectopic tooth in the nasal cavity is a rare phenomenon, especially on the inferior turbinate. In most of the reported cases, no etiological explanation of the intranasal teeth has been suggested or found. In children, intranasal ectopic teeth are usually associated with cleft lip and alveolus. Here, we report a rare case of a pediatric patient with unilateral nasal obstruction due to an intranasal ectopic tooth originating from the inferior turbinate without any facial and dental deformities. This case is unique due to the unusual location of the ectopic tooth and its presentation in a child without facial and dental deformities.

Adsorption of Welan Gum on Montmorillonite and Its Influencing Factors.

Welan gum is one of the most promising polymers used in polymer flooding for enhancing oil recovery, due to its excellent temperature resistance and salt-tolerance performance. However, welan gum, as a polymer with higher molecular weight, can be adsorbed and detained in the pore throat of the reservoir, which is characterized by a smaller size. Montmorillonite, a kind of clay mineral with high content in reservoir rocks, has strong adsorption capacity. Therefore, the adsorption behavior of welan gum on montmorillonite, as well as its influencing factors, are studied in this paper. The results show that the adsorption capacity is 2.07 mg/g. The adsorption capacity decreased with the increase in temperature. Both acidic and alkaline conditions reduced the adsorption capacity. The existence of inorganic salt affected the adsorption capacity. In addition, the higher the cation value, the lower the adsorption capacity. The characterization tests showed that the adsorption of welan gum on montmorillonite was characterized by physical adsorption and surface adsorption, indicating that there were no changes in the internal structure of montmorillonite. This study provides feasible methods to reduce the amount of welan gum adsorbed on montmorillonite, which is of great significance for reducing the permeability damage caused by welan gum adsorption and promoting the application of welan gum in polymer flooding for enhancing oil recovery.

Study on the Relationship between the Relative Molecular Mass of a Polymer Clay Stabilizer and the Permeability of a Tight Reservoir.

Water-sensitivity damage is inevitable during hydraulic fracturing for tight reservoir stimulation. A polymer clay stabilizer is the most effective and commonly used agent for reducing this kind of permeability damage. However, due to the small pore throat radii of tight reservoirs, polymers may be captured and detained, resulting in secondary permeability damage caused by polymer plugging. Therefore, it is necessary to clarify the matching relationship between the relative molecular mass of the clay stabilizer and the permeability of tight cores, which has not been reported yet. In response to this problem, the residual resistance factor and the permeability damage rate of PDMDAAC (poly dimethyl diallyl ammonium chloride, a kind of commonly used polymer clay stabilizer) to tight cores from Xinjiang Oilfield were investigated in cores with permeabilities of 0.10 × 10-3 µm2 (0.08-0.17 × 10-3 µm2), 0.05 × 10-3 µm2 (0.035-0.065 × 10-3 µm2), and 0.01 × 10-3 µm2 (0.007-0.020 × 10-3 µm2) through flow experiments. It was found that the relative molecular masses of PDMDAAC, which did not cause obvious core permeability damage, should be less than 10 000, 5000, and 2000, respectively. In addition, the bridging flocculation principle between the hydrodynamics radius of the clay stabilizer and the radius of the tight core pore throat can be used to explain the matching relationship between the relative molecular mass of the polymer clay stabilizer and the permeability of the tight reservoir. This study points out the direction for the optimization of the polymer clay stabilizer used in tight reservoir hydraulic fracturing and provides some references for the construction of hydraulic fracturing fluid systems for the efficient development of unconventional oil and gas resources.

Automatic Recognition of Laryngoscopic Images Using a Deep-Learning Technique.

OBJECTIVES/HYPOTHESIS: To develop a deep-learning-based computer-aided diagnosis system for distinguishing laryngeal neoplasms (benign, precancerous lesions, and cancer) and improve the clinician-based accuracy of diagnostic assessments of laryngoscopy findings. STUDY DESIGN: Retrospective study. METHODS: A total of 24,667 laryngoscopy images (normal, vocal nodule, polyps, leukoplakia and malignancy) were collected to develop and test a convolutional neural network (CNN)-based classifier. A comparison between the proposed CNN-based classifier and the clinical visual assessments (CVAs) by 12 otolaryngologists was conducted. RESULTS: In the independent testing dataset, an overall accuracy of 96.24% was achieved; for leukoplakia, benign, malignancy, normal, and vocal nodule, the sensitivity and specificity were 92.8% vs. 98.9%, 97% vs. 99.7%, 89% vs. 99.3%, 99.0% vs. 99.4%, and 97.2% vs. 99.1%, respectively. Furthermore, when compared with CVAs on the randomly selected test dataset, the CNN-based classifier outperformed physicians for most laryngeal conditions, with striking improvements in the ability to distinguish nodules (98% vs. 45%, P < .001), polyps (91% vs. 86%, P < .001), leukoplakia (91% vs. 65%, P < .001), and malignancy (90% vs. 54%, P < .001). CONCLUSIONS: The CNN-based classifier can provide a valuable reference for the diagnosis of laryngeal neoplasms during laryngoscopy, especially for distinguishing benign, precancerous, and cancer lesions. LEVEL OF EVIDENCE: NA Laryngoscope, 130:E686-E693, 2020.