Development and validation of a realistic type III esophageal atresia simulator for the training of pediatric surgeons.

BACKGROUND: The technical complexity and limited casuistry of neonatal surgical pathology limit the possibilities of developing the necessary technical competencies by specialists in training. Esophageal atresia constitutes the paradigm of this problem. The use of synthetic 3D models for training is a promising line of research, although the literature is limited. METHODS: We conceptualized, designed, and produced an anatomically realistic model for the open correction of type III oesophageal atresia. We validated it with two groups of participants (experts and non-experts) through face, construct, and content-validity questionnaires. RESULTS: The model was validated by nine experts and nine non-experts. The mean procedure time for the experts and non-experts groups was 34.0 and 38.4 min, respectively. Two non-experts did not complete the procedure at the designed time (45 min). Regarding the face validity questionnaire, the mean rating of the model was 3.2 out of 4. Regarding the construct validity, we found statistically significant differences between groups for the equidistance between sutures, 100% correct in the expert group vs. 42.9% correct in the non-expert group (p = 0.02), and for the item "Confirms that tracheoesophageal fistula closure is watertight before continuing the procedure", correctly assessed by 66.7% of the experts vs. by 11.1% of non-experts (p = 0.05). Concerning content validity, the mean score was 3.3 out of 4 for the experts and 3.4 out of 4 for the non-experts. CONCLUSIONS: The present model is a cost-effective, simple-to-produce, and validated option for training open correction of type III esophageal atresia. However, future studies with larger sample sizes and blinded validators are needed before drawing definitive conclusions.

Ocular surface analysis and automatic non-invasive assessment of tear film breakup location, extension and progression in patients with glaucoma.

BACKGROUND: Tear film stability is the key event in ocular surface diseases. The purpose of this study is to evaluate spatial and temporal progression of the tear film breakup using an automatic non-invasive device. METHODS: Non-invasive tear breakup time (NITBUT) parameters, such as First NITBUT (F-NITBUT) and Average NITBUT (A-NITBUT), were evaluated in 132 glaucoma and 87 control eyes with the Keratograph 5 M device. Further analysis of this data was used to determine size, location and progression of tear film breakup with automatically identified breakup areas (BUA). The progression from First BUA (F-BUA) to total BUA (T-BUA) was expressed as Dry Area Growth Rate (DAGR). Differences between both groups were analysed using Student t-test for parametric data and Mann-Whitney U test for non-parametric data. Pearson's correlation coefficient was used to assess the relationship between parametric variables and Spearman in the case of non-parametric variables. RESULTS: F-NITBUT was 11.43 ± 7.83 s in the control group and 8.17 ± 5.73 in the glaucoma group (P = 0.010). A-NITBUT was 14.04 ± 7.21 and 11.82 ± 6.09 s in control and glaucoma groups, respectively (P = 0.028). F-BUA was higher in the glaucoma group than in the control group (2.73 and 2.28; P = 0.022) and was more frequently located at the centre of the cornea in the glaucoma group (P = 0.039). T-BUA was also higher in the glaucoma group than in the control group (13.24 and 9.76%; P = 0.012) and the DAGR was steeper in the glaucoma group than in the control group (34.38° and 27.15°; P = 0.009). CONCLUSIONS: Shorter NITBUT values and bigger, more central tear film breakup locations were observed in the glaucoma group than in the control group. The DAGR indicates that tear film rupture is bigger and increases faster in glaucomatous eyes than in normal eyes.