Microbial Composition and Diversity of High-demand Street-vended Foods in Ecuador.

Developing countries such as Ecuador carry a heavy food safety burden but reports on the microbiological quality of their foods are scarce. In this investigation, the microbial diversity of 10 high-risk and mass-consumption street-vended foods including bolones, encebollado, food dressings, ceviche, chopped fruits, fruit juices, fruit salads, cheese, raw chicken, and ground beef in Quito, Guayaquil, and Cuenca, three major population centers in Ecuador, were evaluated using 16S rRNA gene High Throughput Sequencing. In total, 1,840 amplicon sequence variants (ASVs) were classified into 23 phyla, 253 families, 645 genera, and 829 species. In the tested food samples, Proteobacteria and Firmicutes were the most abundant phyla accounting for 97.41% of relative abundance (RA). At genus level, 10 dominant genera were identified: Acinetobacter (12.61% RA), Lactococcus (12.08% RA), Vibrio (8.23% RA), Weissella (7.43% RA), Aeromonas (6.18% RA), Photobacterium (6.32% RA), Pseudomonas (3.92% RA), Leuconostoc (3.51% RA), Klebsiella (3.49% RA), and Cupriavidus (2.86% RA). The highest microbial diversity indices were found in raw chicken, encebollados, fruit salads, and fruit juices from Guayaquil and Cuenca. From sampled foods, 29 species were classified as food spoilage bacteria and 24 as opportunistic pathogenic bacteria. Two groups associated with human diseases were identified, including 11 enteric species and 26 species of fecal bacteria. The occurrence of recognized and opportunistic pathogenic bacteria, as well as enteric and fecal microorganisms, in the street-vended foods indicated extensive risks for the consumers' health. This study demonstrated the application of culture-independent amplicon sequencing in providing a more comprehensive view of microbial safety for street-vended food, which could be a useful tool to facilitate the control of foodborne diseases.

Aversion to Mesh Use in Pelvic Floor Surgery in a Latina Population at the U.S.-Mexico Border.

IMPORTANCE: Limited studies have examined patient aversion to mesh use in pelvic surgery, especially in Latinas. OBJECTIVE: This study aimed to assess aversion to pelvic surgery with mesh for urinary incontinence and pelvic organ prolapse in a sample of Latinas on the U.S.-Mexico border. STUDY DESIGN: This was a cross-sectional study of self-identified Latinas with symptoms of pelvic floor disorders, recruited at their initial consultation visit at a single, academic urogynecology clinic. Participants completed a validated survey to assess perceptions of mesh use in pelvic surgery. Participants also completed questionnaires assessing the presence and severity of pelvic floor symptoms and level of acculturation. The primary outcome was aversion to mesh surgery, as indicated by a response of "yes" or "maybe" to the question "Based on what you already know, would you avoid surgery using mesh?" Descriptive analysis, univariate relative risk, and linear regression analysis were completed to identify characteristics associated with mesh avoidance. Significance was assessed and considered at P values <0.05. RESULTS: Ninety-six women were included. Only 6.3% had prior pelvic floor surgery using mesh. Sixty-six percent indicated that they would be likely to avoid pelvic surgery that uses mesh. Only 9.4% indicated that they obtained information regarding mesh directly from medical professionals. Levels of concern regarding the use of mesh varied widely (29.2% not worried, 19.1% somewhat worried, 16.9% very worried). Higher percentages of "more acculturated" participants indicated a desire to avoid mesh surgery (58.7% vs 27.3%, P < 0.05). CONCLUSIONS: In this Latina population, a majority of patients indicated an aversion to using mesh in pelvic surgery. Few patients obtained information regarding mesh directly from medical professionals, relying instead on nonmedical sources.

Autogenous cerebral processes: an invitation to look at the brain from inside out.

While external stimulation can reliably trigger neuronal activity, cerebral processes can operate independently from the environment. In this study, we conceptualize autogenous cerebral processes (ACPs) as intrinsic operations of the brain that exist on multiple scales and can influence or shape stimulus responses, behavior, homeostasis, and the physiological state of an organism. We further propose that the field should consider exploring to what extent perception, arousal, behavior, or movement, as well as other cognitive functions previously investigated mainly regarding their stimulus-response dynamics, are ACP-driven.

Neuronal Population Activity in Macaque Visual Cortices Dynamically Changes through Repeated Fixations in Active Free Viewing.

During free viewing, we move our eyes and fixate on objects to recognize the visual scene of our surroundings. To investigate the neural representation of objects in this process, we studied individual and population neuronal activity in three different visual regions of the brains of macaque monkeys (Macaca fuscata): the primary and secondary visual cortices (V1, V2) and the inferotemporal cortex (IT). We designed a task where the animal freely selected objects in a stimulus image to fixate on while we examined the relationship between spiking activity, the order of fixations, and the fixated objects. We found that activity changed across repeated fixations on the same object in all three recorded areas, with observed reductions in firing rates. Furthermore, the responses of individual neurons became sparser and more selective with individual objects. The population activity for individual objects also became distinct. These results suggest that visual neurons respond dynamically to repeated input stimuli through a smaller number of spikes, thereby allowing for discrimination between individual objects with smaller energy.

Hidden lymphoma in the appendix: a case of primary appendiceal diffuse large B-cell lymphoma presenting as acute appendicitis.

The occurrence of diffuse large B-cell lymphoma (DLBCL) of the appendix presenting as acute appendicitis is rare, constituting only a minuscule portion (0.015%) of gastrointestinal lymphoma cases. We present a case of a 55-year-old woman that was admitted to the emergency department with symptoms of acute appendicitis and underwent an interval laparoscopic appendectomy with a right hemicolectomy and lymph node resection. Pathological examination revealed the presence of DLBCL in the appendix. The patient is undergoing chemotherapy.

Effects of the self-perceived sensorimotor demand and immersion during video gaming on visual-attention skills.

Playing specific genres of video games (e.g., action video games) has been linked to improvements in cognitive skills mostly related to attentional phenomena. Nonetheless, do video games have features or dimensions in common that impact cognitive improvements beyond the game genre? Here, we argue that the sensorimotor demand-the amount of demand for precise coordination between movement and perception-is a key element in the improvements associated with playing video games. We conducted a two-part study to test this hypothesis: a self-report online gaming instrument development and validation and an in-lab behavioural and electrophysiological study. In the first study, data from 209 participants were used to devise the sensorimotor demand instrument (SMDI). The SMDI was split into three dimensions of video game playing: sensorimotor contingency, immersion and unfocused gaming. Criterion validity related to video gamers' characteristics supported that the SMDI is sensitive to the input device (e.g., keyboard or touchscreens), and the most recent experience gained during gaming sessions while not being sensitive to the game genre. In the second study, data from 20 participants who performed four visual-attentional tasks previously reported in the literature showed that the SMDI's dimensions were associated with behavioural performance measures and the latency and amplitude of event-related potentials (N1, P2 and P3). Despite the challenge of studying the video gamer population, our study remarks on the relevance of sensorimotor demands in the performance of attentional tasks and its potential use as a dimension to characterize the experience of playing video games beyond the game genre.

Event-related (de)synchronization and potential in whole vs. part sensorimotor learning.

Background: There are different ways to learn a sensorimotor task. This research focuses on whole versus part learning in a complex video game that involves sensorimotor adaptations and skill learning. The primary aim of this research is to compare the changes in (1) event-related potentials (ERP) and (2) Alpha and Beta event-related desynchronization/synchronization [ERD(S)] of EEG between whole and part practice protocols. Materials and methods: 18 Healthy young participants practiced for 5 days a video game with distorted kinematic (advancing skill) and dynamic features (shooting skill) to test the ability to combine sensorimotor skill components learned modularly (part learning, 9 participants) or combined (whole practice, 9 participants). We examined ERP and ERD(S) in EEG channels in the baseline test (day 1) and the retention test (day 5), dissociating epochs with advancing or shooting. We focus the analysis on the main activity of ERP or ERD(S) in different time windows. Results: In the advancing epochs (distorted kinematic), both groups showed a decrease in time for ERP and an increase in Beta ERD activity in central and posterior channels. In the shooting epochs (distorted dynamic), the Whole group showed a decrease in time for ERPs in anterior and central-posterior channels. Additionally, the shooting ERS in the Beta band decreases within sessions in central channels, particularly for the Part group. Conclusion: Neural correlates of kinematic and dynamic control [ERP and ERD(S)] were modulated by sensorimotor learning, which reflects the effect of the type of practice on the execution and the evaluation of the action. These results can be linked with our previous report, where the simultaneous practice of kinematic and dynamic distortions takes advantage of the motor performance on retention tests, indicating a more automatic control for the whole practice group.

Perforated mediastinal gastric volvulus: an uncommon complication of hiatal hernia.

A woman in her 50s was admitted to the emergency department with a 3-day history of abdominal pain, mainly in the right hypochondrium, radiating to the back, associated with postprandial vomiting and dysphagia. The abdominal ultrasound study found no abnormalities. Laboratory tests showed increased C-reactive protein levels, creatinine and high white blood cell count without a left shift. Abdominal computed tomography scan exhibited mediastinal herniation, twist and perforation of the gastric fundus associated with air-fluid levels in the lower mediastinum. The patient underwent diagnostic laparoscopy requiring laparotomy conversion due to hemodynamic instability related to the pneumoperitoneum. During the intensive care unit (ICU) stay, thoracoscopy with pulmonary decortication was performed to treat complicated pleural effusion. After ICU and standard infirmary bed recovery, the patient was discharged from the hospital. This report illustrates a case of perforated gastric volvulus as the cause of nonspecific abdominal pain.

SaFiDe: Detection of saccade and fixation periods based on eye-movement attributes from video-oculography, scleral coil or electrooculography data.

In this work we present SaFiDe, a deterministic method to detect eye movements (saccades and fixations) from eye-trace data. We developed this method for human and nonhuman primate data from video- and coil-recorded eye traces and further applied the algorithm to eye traces computed from electrooculograms. All the data analyzed were from free-exploration paradigms, where the main challenge was to detect periods of saccades and fixations that were uncued by the task. The method uses velocity and acceleration thresholds, calculated from the eye trace, to detect saccade and fixation periods. We show that our fully deterministic method detects saccades and fixations from eye traces during free visual exploration. The algorithm was implemented in MATLAB, and the code is publicly available on a GitHub repository.•The algorithm presented is entirely deterministic, simplifying the comparison between subjects and tasks.•Thus far, the algorithm presented can operate over video-based eye tracker data, human electrooculogram records, or monkey scleral eye coil data.

Combined therapy of bilateral transcranial direct current stimulation and ocular occlusion improves visual function in adults with amblyopia, a randomized pilot study.

Background: Amblyopia is the interocular visual acuity difference of two lines or more with the best correction in both eyes. It is treated with ocular occlusion therapy, but its success depends on neuroplasticity, and thus is effective in children but not adults. Transcranial Direct Current Stimulation (tDCS) is suggested to increase neuroplasticity. Objective: To determine if combined intervention of bilateral tDCS and ocular occlusion improves visual function in adults with amblyopia. Methods: A double-blind randomized, controlled pilot trial was conducted in 10 volunteers with amblyopia. While applying ocular occlusion and performing a reading task, participants received bilateral tDCS (n = 5) or sham stimulation (n = 5), with the anodal tDCS electrode in the contralateral visual cortex and the cathodal in the ipsilateral visual cortex in relation to the amblyopic eye. Visual function (through visual acuity, stereopsis, and contrast sensitivity tests) and visual evoked potential (with checkerboard pattern stimuli presentation) were evaluated immediately after. Results: A total of 30 min after treatment with bilateral tDCS, visual acuity improved by 0.16 (± 0.025) LogMAR in the treatment group compared with no improvement (-0.02 ± 0.02) in five controls (p = 0.0079), along with a significant increase in the amplitude of visual evoked potentials of the amblyopic eye response (p = 0.0286). No significant changes were observed in stereopsis and contrast sensitivity. No volunteer reported any harm derived from the intervention. Conclusion: Our study is the first to combine anodal and cathodal tDCS for the treatment of amblyopia, showing transient improved visual acuity in amblyopic adults.

Visual-spatial processing impairment in the occipital-frontal connectivity network at early stages of Alzheimer's disease.

Introduction: Alzheimer's disease (AD) is the leading cause of dementia worldwide, but its pathophysiological phenomena are not fully elucidated. Many neurophysiological markers have been suggested to identify early cognitive impairments of AD. However, the diagnosis of this disease remains a challenge for specialists. In the present cross-sectional study, our objective was to evaluate the manifestations and mechanisms underlying visual-spatial deficits at the early stages of AD. Methods: We combined behavioral, electroencephalography (EEG), and eye movement recordings during the performance of a spatial navigation task (a virtual version of the Morris Water Maze adapted to humans). Participants (69-88 years old) with amnesic mild cognitive impairment-Clinical Dementia Rating scale (aMCI-CDR 0.5) were selected as probable early AD (eAD) by a neurologist specialized in dementia. All patients included in this study were evaluated at the CDR 0.5 stage but progressed to probable AD during clinical follow-up. An equal number of matching healthy controls (HCs) were evaluated while performing the navigation task. Data were collected at the Department of Neurology of the Clinical Hospital of the Universidad de Chile and the Department of Neuroscience of the Faculty of Universidad de Chile. Results: Participants with aMCI preceding AD (eAD) showed impaired spatial learning and their visual exploration differed from the control group. eAD group did not clearly prefer regions of interest that could guide solving the task, while controls did. The eAD group showed decreased visual occipital evoked potentials associated with eye fixations, recorded at occipital electrodes. They also showed an alteration of the spatial spread of activity to parietal and frontal regions at the end of the task. The control group presented marked occipital activity in the beta band (15-20 Hz) at early visual processing time. The eAD group showed a reduction in beta band functional connectivity in the prefrontal cortices reflecting poor planning of navigation strategies. Discussion: We found that EEG signals combined with visual-spatial navigation analysis, yielded early and specific features that may underlie the basis for understanding the loss of functional connectivity in AD. Still, our results are clinically promising for early diagnosis required to improve quality of life and decrease healthcare costs.

Laparoscopic hepp couinaud for the treatment of caroli's disease: a case report / Hepp Couinaud laparoscópica para el tratamiento de la enfermedad de Caroli: reporte de caso

Caroli disease is a rare congenital disorder characterized by dilatation of intrahepatic bile ducts. The treatment could correspond to hepatic resection for localized disease. This paper describes a case of Caroli's disease in a 60 years old female patient, who presented jaundice and diffuse abdominal pain. Further examinations suggested the diagnosis of Caroli disease associated with cholestatic syndrome. We decided to perform a Hepp Couinaud biliodigestive bypass by video laparoscopy with Roux-en-Y reconstruction. There were no immediate complications and no longterm complications after 6 months of follow-up. The VLP biliodigestive bypass in patients with associated cholestatic syndromes should be considered a treatment prior to a more aggressive approach.

La enfermedad de Caroli es un raro trastorno congénito que consiste en una dilatación de las vías biliares intrahepáticas. Su tratamiento definitivo debe consistir en resección hepática por la enfermedad localizada. Este artículo describe un caso de enfermedad de Caroli en una paciente de sexo femenino de 60 años de edad, quien presentó ictericia y dolor abdominal difuso. Exámenes posteriores sugirieron el diagnóstico de enfermedad de Caroli asociada con síndrome colestásico. Los médicos decidieron realizar un bypass biliodigestivo de Hepp Couinaud mediante videolaparoscopia con reconstrucción en Y de Roux. No hubo complicaciones inmediatas ni complicaciones a largo plazo después de 6 meses de seguimiento. El bypass biliodigestivo VLP en pacientes con síndromes colestásicos asociados debe considerarse un tratamiento previo a un abordaje más agresivo.

Voluntary self-initiation of the stimuli onset improves working memory and accelerates visual and attentional processing.

The ability of an organism to voluntarily control the stimuli onset modulates perceptual and attentional functions. Since stimulus encoding is an essential component of working memory (WM), we conjectured that controlling the initiation of the perceptual process would positively modulate WM. To corroborate this proposition, we tested twenty-five healthy subjects in a modified-Sternberg WM task under three stimuli presentation conditions: an automatic presentation of the stimuli, a self-initiated presentation of the stimuli (through a button press), and a self-initiated presentation with random-delay stimuli onset. Concurrently, we recorded the subjects' electroencephalographic signals during WM encoding. We found that the self-initiated condition was associated with better WM accuracy, and earlier latencies of N1, P2 and P3 evoked potential components representing visual, attentional and mental review of the stimuli processes, respectively. Our work demonstrates that self-initiated stimuli enhance WM performance and accelerate early visual and attentional processes deployed during WM encoding. We also found that self-initiated stimuli correlate with an increased attentional state compared to the other two conditions, suggesting a role for temporal stimuli predictability. Our study remarks on the relevance of self-control of the stimuli onset in sensory, attentional and memory updating processing for WM.

Cortico-Hippocampal Oscillations Are Associated With the Developmental Onset of Hippocampal-Dependent Memory.

Hippocampal-dependent memories emerge late during postnatal development, aligning with hippocampal maturation. During sleep, the two-stage memory formation model states that through hippocampal-neocortical interactions, cortical slow-oscillations (SO), thalamocortical Spindles, and hippocampal sharp-wave ripples (SWR) are synchronized, allowing for the consolidation of hippocampal-dependent memories. However, evidence supporting this hypothesis during development is still lacking. Therefore, we performed successive object-in-place tests during a window of memory emergence and recorded in vivo the occurrence of SO, Spindles, and SWR during sleep, immediately after the memory encoding stage of the task. We found that hippocampal-dependent memory emerges at the end of the 4th postnatal week independently of task overtraining. Furthermore, we observed that those animals with better performance in the memory task had increased Spindle density and duration and lower density of SWR. Moreover, we observed changes in the SO-Spindle and Spindle-SWR temporal-coupling during this developmental period. Our results provide new evidence for the onset of hippocampal-dependent memory and its relationship to the oscillatory phenomenon occurring during sleep that helps us understand how memory consolidation models fit into the early stages of postnatal development.

Alpha EEG Activity and Pupil Diameter Coupling during Inactive Wakefulness in Humans.

Variations in human behavior correspond to the adaptation of the nervous system to different internal and environmental demands. Attention, a cognitive process for weighing environmental demands, changes over time. Pupillary activity, which is affected by fluctuating levels of cognitive processing, appears to identify neural dynamics that relate to different states of attention. In mice, for example, pupil dynamics directly correlate with brain state fluctuations. Although, in humans, alpha-band activity is associated with inhibitory processes in cortical networks during visual processing, and its amplitude is modulated by attention, conclusive evidence linking this narrowband activity to pupil changes in time remains sparse. We hypothesize that, as alpha activity and pupil diameter indicate attentional variations over time, these two measures should be comodulated. In this work, we recorded the electroencephalographic (EEG) and pupillary activity of 16 human subjects who had their eyes fixed on a gray screen for 1 min. Our study revealed that the alpha-band amplitude and the high-frequency component of the pupil diameter covariate spontaneously. Specifically, the maximum alpha-band amplitude was observed to occur ∼300 ms before the peak of the pupil diameter. In contrast, the minimum alpha-band amplitude was noted to occur ∼350 ms before the trough of the pupil diameter. The consistent temporal coincidence of these two measurements strongly suggests that the subject's state of attention, as indicated by the EEG alpha amplitude, is changing moment to moment and can be monitored by measuring EEG together with the diameter pupil.

Latency shortening with enhanced sparseness and responsiveness in V1 during active visual sensing.

In natural vision, neuronal responses to visual stimuli occur due to self-initiated eye movements. Here, we compare single-unit activity in the primary visual cortex (V1) of non-human primates to flashed natural scenes (passive vision condition) to when they freely explore the images by self-initiated eye movements (active vision condition). Active vision enhances the number of neurons responding, and the response latencies become shorter and less variable across neurons. The increased responsiveness and shortened latency during active vision were not explained by increased visual contrast. While the neuronal activities in all layers of V1 show enhanced responsiveness and shortened latency, a significant increase in lifetime sparseness during active vision is observed only in the supragranular layer. These findings demonstrate that the neuronal responses become more distinct in active vision than passive vision, interpreted as consequences of top-down predictive mechanisms.

Modelling Worldviews as Stable Metabolisms.

The emergence and evolution of worldviews is a complex phenomenon that requires strong and rigorous scientific attention in our hyperconnected world. On the one hand, cognitive theories have proposed reasonable frameworks but have not reached general modeling frameworks where predictions can be tested. On the other hand, machine-learning-based applications perform extremely well at predicting outcomes of worldviews, but they rely on a set of optimized weights in a neural network that does not comply to a well-founded cognitive framework. In this article, we propose a formal approach used to investigate the establishment of and change in worldviews by recalling that the realm of ideas, where opinions, perspectives and worldviews are shaped, resemble, in many ways, a metabolic system. We propose a general modelization of worldviews based on reaction networks, and a specific starting model based on species representing belief attitudes and species representing belief change triggers. These two kinds of species combine and modify their structures through the reactions. We show that chemical organization theory combined with dynamical simulations can illustrate various interesting features of how worldviews emerge, are maintained and change. In particular, worldviews correspond to chemical organizations, meaning closed and self-producing structures, which are generally maintained by feedback loops occurring within the beliefs and triggers in the organization. We also show how, by inducing the external input of belief change triggers, it is possible to change from one worldview to another, in an irreversible way. We illustrate our approach with a simple example reflecting the formation of an opinion and a belief attitude about a theme, and, next, show a more complex scenario containing opinions and belief attitudes about two possible themes.

Extending the integrate-and-fire model to account for metabolic dependencies.

It is widely accepted that the brain, like any other physical system, is subjected to physical constraints that restrict its operation. The brain's metabolic demands are particularly critical for proper neuronal function, but the impact of these constraints continues to remain poorly understood. Detailed single-neuron models are recently integrating metabolic constraints, but these models' computational resources make it challenging to explore the dynamics of extended neural networks, which are governed by such constraints. Thus, there is a need for a simplified neuron model that incorporates metabolic activity and allows us to explore the dynamics of neural networks. This work introduces an energy-dependent leaky integrate-and-fire (EDLIF) neuronal model extension to account for the effects of metabolic constraints on the single-neuron behavior. This simple, energy-dependent model could describe the relationship between the average firing rate and the Adenosine triphosphate (ATP) cost as well as replicate a neuron's behavior under a clinical setting such as amyotrophic lateral sclerosis (ALS). Additionally, EDLIF model showed better performance in predicting real spike trains - in the sense of spike coincidence measure - than the classical leaky integrate-and-fire (LIF) model. The simplicity of the energy-dependent model presented here makes it computationally efficient and, thus, suitable for studying the dynamics of large neural networks.

Perceptions of Mesh Use for Pelvic Floor Surgery in Latinas: Face Validity of a Spanish Questionnaire.

OBJECTIVE: The aim of the study was to validate a Spanish-translated survey assessing patients' perceptions of mesh use in pelvic floor surgery. METHODS: An English-language survey evaluating perceptions of mesh use underwent a process of Spanish translation and validation, using a forward-backward translation validation protocol. Self-identified bilingual Latinas with symptoms of pelvic floor disorders were recruited to participate in cognitive interviews after completing the survey in English and Spanish. κ coefficient and Cronbach α were calculated for measurement of reliability and internal consistency in responses. A P value of 0.05 was considered statistically significant. RESULTS: A total of 30 women were randomized to complete the initial survey in either English or Spanish. Demographics for the 2 cohorts were similar. For the Spanish-translated survey overall, 86% described the questions as "somewhat easy" or "very easy" to understand, and 93% reported that it was "clear" or "very clear" that the survey aimed to investigate their thoughts regarding mesh use. Approximately 63% of the participants expressed confusion over the use of the Spanish medical term "cabestrillo," translated for "sling." There were no significant differences in the responses on cognitive interview between the 2 groups. Overall, the responses between English and Spanish versions of the survey demonstrated good reliability and internal consistency. CONCLUSIONS: This study demonstrated face validity of a Spanish-translated survey assessing perceptions of mesh use in pelvic surgery in a Latina population. Participants' feedback was crucial to optimizing the quality of the survey for future studies that will evaluate Spanish-speaking patients' views of mesh implants in pelvic reconstructive surgery.

A Structured, Hybrid Cystoscopy Simulation Curriculum for Obstetrics/Gynecology Residents.

OBJECTIVES: This study aimed to assess the subjective and objective cystoscopy skills of gynecology residents before and after implementation of a comprehensive simulation curriculum. METHODS: Residents in an obstetrics/gynecology program at a single academic institution participated in a 6-week cystoscopy simulation course. Residents attended an initial orientation and didactic presentation, and then weekly 20- to 30-minute training sessions using a water balloon model and a virtual reality simulator. Pretesting and posttesting were performed, including (1) subjective self-assessments, (2) a written quiz, and (3) objective structured assessment of technical skills. Paired t test was used to assess the differences in residents' objective assessment scores before and after simulation training. RESULTS: A total of 16 residents were recruited. Residents reported significant subjective improvements in comfort, confidence, and proficiency in performing cystoscopy after completing the curriculum. Their overall objective assessment improved, including written quiz scores (mean score, 49% vs 78%; P < 0.001), efficiency in cystoscope assembly (means score, 0 vs 4; P < 0.001), overall bladder survey score (56% vs 86%, P < 0.001), and global rating score (mean score, 15 vs 24; P < 0.001). Residents tended to prefer the water-balloon model compared with the virtual reality simulator (75% vs 25%). CONCLUSIONS: Obstetrics/gynecology residents demonstrated significant improvements in subjective and objective measures of skill after completion of a 6-week cystoscopy simulation training course using a combination of low- and high-fidelity models. Although universal cystoscopy at the time of hysterectomy for benign indications remains controversial, cystoscopy simulation should remain an important part of resident training.