Revisiting Javal's rule: a fresh and improved power vector approach according to age.

PURPOSE: The scientific community has established Javal's rule as a model linking refractive (RA) and keratometric (KA) astigmatism since its appearance more than 100 years ago. The aim was to improve the accuracy of this relationship according to subject's age by applying the power vector analysis. Posterior corneal curvature has also been studied. METHODS: The IOLMaster 700 optical biometer was used to measure the corneal thickness and the radius of curvature of the anterior and posterior corneal surfaces. Refractive error was determined by a non-cycloplegic subjective refraction process with trial lenses. Linear regression analyses were applied using J0 and J45 power vector components. An evaluation was carried out according to the subject's age resulting into eight regression relationships for each astigmatic vector component for each relationship. RESULTS: A total of 2254 right eyes from 2254 healthy subjects were evaluated. A trend towards against-the-rule astigmatism (ATR) was found with aging, both for refractive astigmatism (RA) and keratometric astigmatism (KA), with 95.2% of subjects under 20 years old having with-the-rule (WTR) KA, and only 22.8% above 79 years old. The following regression equations were found between RA and KA: [Formula: see text] = 0.73 × [Formula: see text] - 0.18 (R = 0.78) and [Formula: see text] = 0.70 × [Formula: see text] + 0.04 (R = 0.69) and between RA and total corneal astigmatism (TCA): [Formula: see text] = 0.73 × [Formula: see text] + 0.13 (R=0.78) and [Formula: see text] = 0.70 × [Formula: see text] - 0.06 (R = 0.68) for the whole sample, but with sensible differences among age groups, both in the slope and in the intercept. CONCLUSION: Ignoring the age of the subject when using Javal's rule could lead to an error in the final cylinder calculation that would increase in high astigmatisms. Applying this new power vector approach based on subject's age could improve the accuracy of the astigmatism prediction.

Photographic Parameters in Three-Dimensional Facial Image Acquisition. A Scoping Review.

OBJECTIVE: Orthognathic surgery is a viable and reproducible treatment for facial deformities. Despite the precision of the skeletal planning of surgical procedures, there is little information about the relations between hard and soft tissues in three-dimensional (3D) analysis, resulting in unpredictable soft tissue outcomes. Three-dimensional photography is a viable tool for soft tissue analysis because it is easy to use, has wide availability, low cost, and is harmless. This review aims to establish parameters for acquiring consistent and reproducible 3D facial images. METHODS: A scoping review was conducted across PubMed, SCOPUS, Scientific Electronic Library Online (SciELO), and Web of Science databases, adhering to "Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews" guidelines. Articles presenting 3D facial photographs in the diagnostic phase were considered. RESULTS: A total of 79 articles were identified, of which 29 were selected for analysis. CONCLUSION: The predominant use of automated systems like 3dMD and VECTRA M3 was noted. User positioning has highest agreement among authors. Noteworthy aspects include the importance of proper lighting, facial expression, and dental positioning, with observed discrepancies and inconsistencies among authors. Finally, the authors proposed a 3D image acquisition protocol based on this research findings.

Mandibular Notch Contouring in Temporomandibular Joint Replacement. Technical Note.

Temporomandibular Joint Replacement (TMJ-R) is used to treat maxillomandibular disease related to condylar head augmentation, condylar head reduction, absence of the condylar head and TMJ reconstruction. In most of the cases, TMJ-R could be used together with orthognathic surgery. In cases with facial asymmetry related to overgrowth of the mandibular condyle as in the cases of osteochondroma, there is a progressive facial asymmetry with enlargement of the unilateral mandibular ramus and mandibular body, creating strong mandibular contouring when comparing to the contralateral side. Usually, in this case, a lack is observed in the antegonial notch. ​The aim of this technical note ​is to provide the strategy to obtain facial symmetry using the TMJ prosthesis and contouring osteotomy in the same procedure.

Mandibular Contouring in Subjects With Class II or Class III Dentofacial Deformities and Treatment Needs.

Facial contouring relates to hard and soft structures that make up the face. Skeletal class II and III subjects present bone structure and position changes, significantly impacting the soft tissues. This study aims to analyze the morphology of the mandible at mandibular ramus and angle level in subjects with skeletal facial deformity class II and III who are candidates for orthognathic surgery and to define implications in facial contour. A cross-sectional study used cone beam computed tomography to compare the mandibular contour (mandibular angle and ramus region) in orthognathic surgery candidates. One hundred sixty orthognathic surgery candidates were analyzed, ranging in age from 18 to 58 years (31.29 ± 11.97). Regarding the skeletal class, 95 (59.37%) were skeletal class II, and 65 (40.62%) were skeletal class III. Class II subjects had a larger antegonial notch than class III subjects. Concerning the mandibular contour, class II subjects presented less vertical distance than class III subjects, but both presented similar gonial angles. Concerning the ideas to assess the need for mandibular contouring surgery, the 2 proposals to determine the need for mandibular contouring surgery in class II and III subjects present a similar distribution. The mandibular notch is an objective element and is commonly present in subjects with a class II facial pattern; this element can be used in contour analysis to define expected facial characteristics, including the patient's facial sex, in the decision of surgical techniques for lower facial contour augmentation or reduction.

Comparison Between an Expert Operator an Inexperienced Operator, and Artificial Intelligence Software: A Brief Clinical Study of Cephalometric Diagnostic.

INTRODUCTION: Artificial intelligence (AI) is constantly developing in several medical areas and has become useful to assist with treatment planning. Orthodontics and maxillofacial surgery use AI-based technology to identify and select cephalometric points for diagnostics. Although some studies have shown promising results from the use of AI, the evidence is still limited. Hence, additional investigation is justified. MATERIALS AND METHODS: In this retrospective study, 2 human operators (1 expert and 1 inexperienced) and 1 software analyzed 30 lateral cephalograms of individuals with orthodontic treatment indications. They measured 10 cephalometric variables and then 2 weeks later, repeated measurements on 30% of the sample. We evaluated the reliability of the measurements between the 2-time points and the differences in the means between the expert operator and the AI software and between the expert and inexperienced operators. RESULTS: There was high reliability for the expert operator and AI measurements, and moderate reliability for the inexperienced operator measurements. There were some significant differences in the means produced by the AI software and the inexperienced operator compared with the expert operator. CONCLUSION: Although AI is useful for cephalometric analysis, it should be used with caution because there are differences compared with analysis by humans.

Evaluation of trefoil factor 3 as a non-invasive biomarker of gastric intestinal metaplasia and gastric cancer in a high-risk population.

BACKGROUND: Adenocarcinoma is preceded by chronic atrophic gastritis, gastric intestinal metaplasia and dysplasia. Trefoil factor 3 (TFF3) is a peptide secreted by goblet cells, which is abundantly present in intestinal metaplasia. AIM: To evaluate the utility of serum TFF3 as a non-invasive biomarker for the diagnosis of intestinal metaplasia and gastric cancer. METHODS: Single-center, cross-sectional study of 274 patients who consecutively underwent upper gastrointestinal endoscopy with gastric biopsies (updated Sydney system). TFF3 levels were measured in serum by a commercial ELISA kit. Patients with normal histology or chronic atrophic gastritis without intestinal metaplasia comprised the control group. In addition, 14 patients with invasive gastric cancer were included as a reference group. The association between TFF3 levels and intestinal metaplasia was assessed by logistic regression. RESULTS: Patients with intestinal metaplasia (n=110) had a higher median TFF3 level as compared to controls (n=164), 13.1 vs. 11.9ng/mL, respectively (p=0.024). Multivariable logistic regression showed a no significant association between TFF3 levels and intestinal metaplasia (OR=1.20; 95%CI: 0.87-1.65; p-trend=0.273). The gastric cancer group had a median TFF3 level of 20.5ng/mL, and a significant association was found (OR=3.26; 95%CI: 1.29-8.27; p-trend=0.013). CONCLUSION: Serum levels of TFF3 do not discriminate intestinal metaplasia in this high-risk Latin American population. Nevertheless, we confirmed an association between TFF3 levels and invasive gastric cancer.

After-Action Reviews and Long-Term Performance: An Experimental Examination in the Context of an Emergency Simulation.

OBJECTIVE: The present study examined the effectiveness of after-action reviews (AARs; also known as debriefing) in mitigating skill decay. BACKGROUND: Research on the long-term effectiveness of AARs is meager. To address this gap in the literature, we conducted an experimental study that also overcomes some research design issues that characterize the limited extant research. METHOD: Eighty-four participants were randomly assigned to an AAR or non-AAR condition and trained to operate a PC-based fire emergency simulator. During the initial acquisition phase, individuals in the AAR condition were allowed to review their performance after each practice session, whereas individuals in the non-AAR condition completed a filler task. About 12 weeks later, participants returned to the lab to complete four additional practice sessions using a similar scenario (i.e., the retention and reacquisition phase). RESULTS: The performance of participants in the AAR condition degraded more after nonuse but also recovered faster than the performance of participants in the non-AAR condition, although these effects were fairly small and not statistically significant. CONCLUSION: Consistent with the limited research on the long-term effectiveness of AARs, our findings failed to support their effectiveness as a decay-prevention intervention. Because the present study was conducted in a laboratory setting using a relatively small sample of undergraduate students, additional research is warranted. APPLICATION: Based on the results of the present study, we suggest some additional strategies that trainers might consider to support long-term skill retention when using AARs.

Convolutional Neural Networks for Mechanistic Driver Detection in Atrial Fibrillation.

The maintaining and initiating mechanisms of atrial fibrillation (AF) remain controversial. Deep learning is emerging as a powerful tool to better understand AF and improve its treatment, which remains suboptimal. This paper aims to provide a solution to automatically identify rotational activity drivers in endocardial electrograms (EGMs) with convolutional recurrent neural networks (CRNNs). The CRNN model was compared with two other state-of-the-art methods (SimpleCNN and attention-based time-incremental convolutional neural network (ATI-CNN)) for different input signals (unipolar EGMs, bipolar EGMs, and unipolar local activation times), sampling frequencies, and signal lengths. The proposed CRNN obtained a detection score based on the Matthews correlation coefficient of 0.680, an ATI-CNN score of 0.401, and a SimpleCNN score of 0.118, with bipolar EGMs as input signals exhibiting better overall performance. In terms of signal length and sampling frequency, no significant differences were found. The proposed architecture opens the way for new ablation strategies and driver detection methods to better understand the AF problem and its treatment.

Effects of Cardiac Stem Cell on Postinfarction Arrhythmogenic Substrate.

Clinical data suggest that cardiosphere-derived cells (CDCs) could modify post-infarction scar and ventricular remodeling and reduce the incidence of ventricular tachycardia (VT). This paper assesses the effect of CDCs on VT substrate in a pig model of postinfarction monomorphic VT. We studied the effect of CDCs on the electrophysiological properties and histological structure of dense scar and heterogeneous tissue (HT). Optical mapping and histological evaluation were performed 16 weeks after the induction of a myocardial infarction by transient occlusion of the left anterior descending (LAD) artery in 21 pigs. Four weeks after LAD occlusion, pigs were randomized to receive intracoronary plus trans-myocardial CDCs (IC+TM group, n: 10) or to a control group. Optical mapping (OM) showed an action potential duration (APD) gradient between HT and normal tissue in both groups. CDCs increased conduction velocity (53 ± 5 vs. 45 ± 6 cm/s, p < 0.01), prolonged APD (280 ± 30 ms vs. 220 ± 40 ms, p < 0.01) and decreased APD dispersion in the HT. During OM, a VT was induced in one and seven of the IC+TM and control hearts (p = 0.03), respectively; five of these VTs had their critical isthmus located in intra-scar HT found adjacent to the coronary arteries. Histological evaluation of HT revealed less fibrosis (p < 0.01), lower density of myofibroblasts (p = 0.001), and higher density of connexin-43 in the IC+TM group. Scar and left ventricular volumes did not show differences between groups. Allogeneic CDCs early after myocardial infarction can modify the structure and electrophysiology of post-infarction scar. These findings pave the way for novel therapeutic properties of CDCs.

Retinal detachment after phacoemulsification in refractive surgery clinics: a large series analysis with variable follow-up during 16 years.

PURPOSE: To determine the long-term incidence of pseudophakic retinal detachment (PRD) after phacoemulsification and the weight of the main risk factors in the appearance of such complication in a large sample. To implement a customized formula and a software calculation program able to quantify the risk of suffering PRD applicable to all lens extraction patients. METHODS: Retrospective cumulative risk analysis conducted on 178,515 eyes operated under similar conditions in a group of refractive surgery clinics (Clínica Baviera SL) located in a relatively limited geographical area (Spain). A survival analysis was performed and the data were modelled using the Weibull regression to determine the risk over a period of 16 years and to estimate the association of different risk factors: sex, age, axial length (AXL) of the eye, intraoperative posterior capsule rents (PCR), and YAG laser capsulotomies. The resulting estimates were translated into a predictive equation for hazard rates and survival probabilities. Later, an application was developed to make prediction available for the clinical community in order to estimate the potential risk of any hypothetical case before lens surgery. RESULTS: Globally, 1521 (0.85%) cases of PRD were diagnosed during the period. The risk for PRD was significantly greater in males (5.48 [2.94-10.2]; p < 0.001), in long eyes (1.24 [1.21-1.26]; p < 0.001), and also after posterior capsule rents (13.97 [11.61-16.82]; p < 0.001). Posterior capsule rupture increased the risk of PRD up to fourteen times. CONCLUSIONS: From weaker to stronger impact, age, axial length, sex, and intraoperative posterior capsule rent were significant risk factors for the appearance of PRD after lens extraction.

Efficacy, safety and visual outcomes of cataract surgeries performed during blindness prevention programs in different locations in Kenya.

PURPOSE: To determine the visual outcomes achieved in terms of efficacy and safety during high-volume cataract surgery programs in different locations in Kenya. METHODS: Eight hundred eighty-one eyes of 849 patients underwent extracapsular cataract extraction with intraocular lens implantation in a retrospective, observational, consecutive cohort study on patients who underwent cataract surgery in five programs that a Spanish non-governmental organization conducted between 2013 and 2019 for the prevention of blindness in different geographical areas of Kenya: Thika, Athi River, Kissi, Bagavathi, and Nakuru. The programs were carried out by Spanish and Kenyan surgeons working together. RESULTS: Mean age was 66.81 ± 14.47 years. Fifty-one percent of the operated eyes (447 eyes) were women. 94% of patients belonged to six ethnic groups. The mean uncorrected distance visual acuity (UDVA) before surgery was 1.98 ± 0.98 logMAR (20/2000), which changed to 0.82 ± 0.68 logMAR (20/150) 3 months after surgeries. The corrected distance visual acuity (CDVA) was 0.4 ± 0.53 logMAR (20/50) 3 months after surgery, 77.5% of the patients had good visual outcomes, and 6.3% had poor outcomes. Preoperative UDVAs were significantly different with respect to the different geographical areas (Kruskal-Wallis; p < 0.001). The most common intraoperative complication was posterior capsule rupture (incidence, 4.2%, 37 of 881), and the most serious complication was expulsive hemorrhage (incidence, 0.1%, 1 of 881). CONCLUSIONS: Cataract programs performed in a middle-income country with the proper technique and standardized protocols of action improved the visual outcome of the patients. Dissimilar baseline status was found in different areas regarding preoperative visual acuities. Training programs of local surgeons should be reinforced.

[A new equation to predict urine creatinine values using data from Chilean population]. / Nueva fórmula para estimar creatininuria en población chilena.

BACKGROUND: Evaluation of 24-hour collection accuracy is based on urinary creatinine excretion (UCr), usually using wide ranges indexed by weight. Equations that predict the expected UCr are also available. AIM: To generate an equation for estimating UCr in Chilean population and evaluate its performance in comparison to existing formulas. MATERIAL AND METHODS: A total of 464 24-hour urine collections from outpatients aged between 15 and 88 years old were used. Ninety percent of collections (n = 418) were randomly extracted to assess the association between absolute UCr values with sex, age, height and weight of participants. A formula was created to estimate the 24-hour UCr using a multiple linear regression model. In the remaining 10% of urine collections (n = 46), the performance of this formula and others reported in the literature were tested. RESULTS: Age, sex and weight were significantly associated with 24-hour UCr values. The new equation was able to predict UCr values with a similar accuracy than CKD-EPI and Walser equations and outperformed other equations. CONCLUSIONS: Our equation developed with Chilean values predicts 24-hour UCr values accurately.

Diffractive trifocal pseudophakic intraocular lenses in high myopic eyes: 2-year assessment after implantation.

PURPOSE: To assess the visual outcomes and ocular safety when implanting diffractive trifocal intraocular lenses in a population of high myopic eyes. METHODS: This is a retrospective cumulative clinical study. Two hundred five myopic eyes consecutively operated in the hospitals of Clínica Baviera, Spain, were included. All eyes presented an axial length equal or greater than 26 mm and were treated and examined following the same methodology for at least 2 years. Refractive and visual outcomes and also intraoperative or postoperative complications were tabulated for later analysis. Furthermore, a subjective questionnaire was completed by all patients at the end of the follow-up period. RESULTS: The percentage of eyes that lost two or more lines of corrected distance visual acuity (CDVA) was 5.9%, 11.5% and 10.7% 3, 12 and 48 months after surgeries respectively. However, 33% of eyes gained two or more lines of CDVA 2 years after implantation. Excimer laser correction of residual refractive error was performed after implants in 29.75% of eyes. Uncorrected distance visual acuities (UDVAs) were significantly better 1 year (0.10 ± 0.3 logMAR) and 2 years after the surgeries (0.10 ± 0.14 logMAR) compared with those estimated 3 months postoperatively (0.14 ± 0.15 logMAR; Kruskal-Wallis; p < 0.001). Mean near and intermediate uncorrected visual acuities remained stable from the first to the last postoperative visit (Kruskal-Wallis; p > 0.05 for all comparisons). Of the eyes, 27.31% were diagnosed and treated with yttrium aluminum garnet (YAG) laser after being diagnosed as having posterior capsular opacification. Retinal detachment (RD) was diagnosed in six eyes (2.92%). CONCLUSIONS: Diffractive trifocal IOLs have good efficacy and predictability in high myopic eyes. Retinal concerns should lead the surgeons to explore other alternatives for refractive surgery in young patients without cataracts.

Prevalence and location of the secondary mesiobuccal canal in 1,100 maxillary molars using cone beam computed tomography.

BACKGROUND: Several articles have used cone beam computed tomography (CBCT) to study the morphology of the maxillary molars and to ascertain its ability to visualize the second mesiobuccal canal (MB2); however, its geometric location has not been examined in depth. The aim of this study was to describe in vivo the prevalence and location of the MB2 in the mesiobuccal root of the first maxillary molar (1MM) and the second maxillary molar (2MM) through CBCT imaging. METHODS: Five hundred fifty CBCT images of the 1MM and 550 of the 2MM were analyzed. To detect the MB2 canal, the observation and measurements were done 1 mm apically to the pulpal floor to standardize the methodology. The geometric location of the central point of the MB2 canal (PMB2) was measured in relation to the central point of the mesiobuccal canal (PMB1) and in relation to the line projected between the PMB1 and the central point of the palatal canals (PP). The data were analyzed using descriptive statistics, with a value of P < 0.05 being statistically significant. RESULTS: In the 1MM, the prevalence of the MB2 canal was 69.82% and was more frequent in women (p = 0.005). The distance between PMB1 and PP was 7.64 ± 1.04 mm. The average distance between PMB1 and PMB2 was 2.68 ± 0.49 mm, and for PMB2 and the line projected between the PMB1 and PP canals was 1.25 ± 0.34 mm. In the 2MM, the MB2 canal was identified in 46.91% and was more frequent in men (p = 0.000). The distance between PMB1 and PP was 7.02 ± 1.30. The average distance between PMB1 and PMB2 was 2.41 ± 0.64 mm, and for the PMB2 and the line projected between the PMB1 and PP canals was 0.98 ± 0.33 mm. CONCLUSIONS: The MB2 canal was found in a high percentage of the sample. These results indicate that CBCT is an effective, high-precision diagnostic tool not only for detecting but also locating in vivo the MB2 canal in the mesiobuccal root of upper molars.

Implantable Collamer Lens for Myopia: Assessment 12 Years After Implantation.

PURPOSE: To evaluate the long-term refractive and visual stability and the risks related to the implantation of Implantable Collamer Lens (ICL; STAAR Surgical, Monrovia, CA) phakic intraocular lens (PIOL) for myopia. METHODS: This retrospective, consecutive, cumulative clinical study was performed in a group of 144 eyes implanted with ICL PIOL for myopia. Only the cases with clinical data available 12 years after the implantation were included in the series. Corrected distance visual acuity (CDVA), uncorrected distance visual acuity, spherical equivalent, refractive astigmatism, endothelial cell density, ICL vaulting, and postoperative complications were analyzed. RESULTS: Mean spherical equivalent refraction was -16.90±4.26 diopters (D) preoperatively and -1.77±1.93 D 12 years postoperatively. Mean CDVA at the first and last visit were 0.31±0.19 logMAR and 0.22±0.22 logMAR, respectively (Mann-Whitney U test, P<.001). Twelve years postoperatively, 8.9% of eyes had lost more than two lines of CDVA. The incidence of clinically relevant cataracts (13.88%) was significantly linked to the use of the V3 model ICL (chi-square test, P=.007). During the follow-up period, a significant reduction in PIOL vaulting was observed (Kruskal-Wallis test, P<.05), and the mean endothelial cell density decreased by 19.75%. CONCLUSIONS: The ICL PIOL provided good refractive outcomes and stability in the long term. The incidence of cataracts is low when the latest models of this PIOL are used.

Add-on sulcus-based versus primary in-the-bag multifocal intraocular lens: intraindividual study.

PURPOSE: To compare the clinical outcomes of add-on sulcus-based multifocal and standard in-the-bag multifocal intraocular lens (IOL) implantation. METHODS: Twenty-one patients with unilateral monofocal pseudophakia underwent add-on sulcus-based Acri. LISA 536D multifocal IOL (Carl Zeiss Meditec, Jena, Germany) implantation (add-on multifocal IOL group) and contralateral phacoemulsification with in-the-bag Acri.LISA 376D multifocal IOL (Carl Zeiss Meditec) implantation (primary multifocal IOL group). Uncorrected distance visual acuity, uncorrected near visual acuity, corrected distance visual acuity, distance-corrected near visual acuity, photopic (90 cd/m(2)) distance, near contrast sensitivity, mesopic (5 cd/m(2)) distance contrast sensitivity with and without glare, wavefront aberrations, and complications were measured 6 months postoperatively. RESULTS: Primary in-the-bag multifocal IOLs provided slightly but significantly better uncorrected distance visual acuity (0.08 ± 0.10 vs 0.17 ± 0.15 logMAR, P = .028), uncorrected near visual acuity (0.09 ± 0.17 vs 0.18 ± 0.11 logMAR, P = .005), and corrected distance visual acuity (0.01 ± 0.04 vs 0.04 ± 0.05 logMAR, P = .038). There were no significant differences in distance-corrected near visual acuity, photopic or mesopic contrast sensitivity under different conditions, and wavefront aberrations. Complications included pigment dispersion in one eye (4.8%) and pupillary capture in 2 eyes (9.5%) of the add-on multifocal IOL group. CONCLUSIONS: The secondary add-on sulcus-based multifocal IOL provided useful pseudoaccommodation with vision quality similar to the primary in-the-bag multifocal IOL. The technique should be considered in patients diagnosed as having unilateral or bilateral monofocal pseudophakia seeking near spectacle independence.

Effect of platelet-rich plasma in nerve regeneration after LASIK.

PURPOSE: To investigate the effect of topical eye application of platelet-rich plasma (E-PRP) on the recovery of corneal sensitivity after LASIK and the anatomical recovery of the sub-basal corneal plexus as studied by confocal microscopy. METHODS: This was a randomized, consecutive, controlled, prospective and masked study on 108 myopic eyes receiving LASIK. The main variables of the study were the increase in corneal sensitivity (Cochet-Bonet aesthesiometer; Luneau, Paris, France) and the aspect of the sub-basal nerve plexus (confocal microscope). Additionally, a biomicroscopic study of the epithelial status of the cornea and a subjective questionnaire were completed. Each eye of each patient was assigned to one of two groups: 54 eyes treated with balanced saline solution and 54 fellow eyes receiving PRP drops for 3 months. RESULTS: No significant differences were detected when the corneal sensitivity thresholds were compared at any postoperative visit in both groups (P > .05 for all comparisons). Almost identical sub-basal fiber densities were estimated for both groups before LASIK (t test, P = .66). However, the type and severity of staining detected during the slit-lamp examinations at the first and third month postoperatively were significantly less evident in the E-PRP treatment group (Wilcoxon test, P < .05). CONCLUSIONS: PRP drops have beneficial effects for promoting epithelial status after LASIK but have no positive effect on recovery of corneal sensitivity, probably due to the limited bioavailability of growth factors in corneal stroma when the substance is topically administered.

Efficacy and safety of mass cataract surgery campaign in a developing country.

PURPOSE: To determine the visual outcomes achieved in terms of efficacy and safety during a mass eye surgery campaign in a low-income developing country. METHODS: Three hundred fifteen eyes of 305 patients underwent extracapsular cataract extraction with intraocular lens implantation in a prospective, analytical, experimental, and nonrandomized study on patients who underwent cataract surgery during the campaign that two Spanish nongovernmental organizations conducted in December 2008 in a district hospital in Bobo-Dioulasso (Burkina Faso). RESULTS: Mean age was 61.97 ± 14.39 years. The mean uncorrected distance visual acuity before surgery was 2.17 ± 0.7 (20/3000), which improved to 0.86 ± 0.64 logMAR (20/150) 3 months after cataract surgery. The mean spherical equivalent at 3 months was -0.87 ± 1.90 diopters. The corrected distance visual acuity was 0.52 ± 0.44 logMAR (20/60) 3 months after surgery, 68.7% of the patients had good visual outcomes, and 9.16% had poor outcomes. A total of 41.4% of the operated eyes showed a spherical equivalent within ± 1.00 diopter of emmetropia. The most common intraoperative complication was posterior capsule rupture (incidence, 2.9%, 9 of 315), and the most serious complication was expulsive hemorrhage (incidence, 0.3%, 1 of 315). Three months after surgery, 2.9% (9 of 315) of the eyes was affected by posterior capsular opacity. CONCLUSIONS: A mass cataract campaign performed in a developing country with the proper technique and standardized protocols of action improved the visual outcome of the patients. The rate of incidence of extracapsular extractions is comparable to that estimated for developed countries.

Organizational climate profiles: Identifying meaningful combinations of climate level and strength.

According to situation strength theory, organizational climate should have a stronger effect on group behavior when members' perceptions of the climate are both unambiguous (i.e., very high or very low) and shared than when they are more ambiguous and less shared. In the organizational climate literature, this proposition is typically examined by testing the interaction between climate level (i.e., mean) and strength (i.e., variability); surprisingly, the preponderance of empirical research testing this interaction does not support this theoretical expectation. This may be because the traditional variable-centered approach fails to consider the possibility of overlooked subpopulations consisting of unique combinations of climate level and strength, creating distinct climate profiles. To address this issue, we use a group-centered conceptualization and analyses (i.e., latent profile analysis) to examine the extent to which 302 workgroups (Sample 1) and 107 organizations (Sample 2) evidence statistically and practically meaningful climate profiles. Results revealed four to six distinct climate profiles across multiple climate types were differentially associated with theoretically relevant outcomes, including objective financial measures. Consistent with situation strength theory, groups with strong and favorable profiles tended to have more positive outcomes, whereas groups with weaker, less favorable profiles tended to have less positive outcomes. In contrast, the traditional variable-centered approach was generally unsupportive of an interaction between climate level and strength. Overall, these findings provide evidence that the group-centered approach is a more sensitive statistical modeling technique for testing a fundamental tenet of situation strength theory in the context of organizational climate research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).