Jacobi-Fourier phase masks as ophthalmic elements to correct presbyopia.

PURPOSE: Investigations into the correction of presbyopia have considered lens design, clinical implications and the development of objective metrics such as the visual Strehl ratio. This study investigated the Jacobi-Fourier phase mask as an ophthalmic element in the correction of presbyopia. The goal was to develop a contact or intraocular lens whose performance was largely insensitive to changes in pupil diameter. METHODS: Numerical simulations based on Fourier optics were performed to evaluate three different Jacobi-Fourier polynomials, with the aim of providing a range of clear vision (1 Dioptre (D)). Performance was evaluated for three pupil sizes (6, 4 and 2 mm), while polychromatic images were simulated using three different wavelengths (656.3, 587.6 and 486.1 nm). The Neural Transfer function was included in the simulation. To validate the method and results, we used the Visual Strehl combined objective metric (VSCombined) currently used in visual optics. This metric gives more weight to the phase transfer function and is more suitable for non-symmetrical phase functions. RESULTS: Numerical validation showed the suitability of the Jacobi-Fourier phase masks for extending the range of clear vision of presbyopic eyes, providing a visual acuity of at least 0.10 logMAR (6/7.5 Snellen) at all distances between 1 and 6 m. The results show a range of clear vision of 1D was not affected by changes in pupil size, an increase in retinal image contrast accompanied by image artefact reduction by increasing the radial order of the Jacobi-Fourier phase mask and a reduction of wavelength dependence of the retinal images. These results are supported by simulated images and the objective criterion VSCombined. CONCLUSIONS: The use of Jacobi-Fourier phase masks as ophthalmic elements for presbyopic correction show promising results, with a good range of clear vision and reduced dependence on pupil size and chromatic aberration.

Saccades, pupil response and blink abnormalities in Huntington's disease patients during free viewing.

OBJECTIVE: Video-based eye tracking was used to investigate saccade, pupil, and blink abnormalities among patients with Huntington's disease (HD) who watched sequences of short videos. HD, an autosomal dominant neurodegenerative disorder resulting from a CAG mutation on chromosome 4, produces motor and cognitive impairments including slow or irregular eye movements, which have been studied using structured tasks. METHODS: To explore how HD affects eye movements under instruction free conditions, we assessed 22 HD patients and their age matched controls in a 10-minute video-based free viewing task. RESULTS: Patients with HD experienced a significant reduction in saccade exploration rate following video clip transitions, an increase in pupil reactions to luminance changes after clip transitions, and a significant higher blink rate throughout the task compared to the control group. CONCLUSIONS: These results show that HD has a significant impact on how patients visually explore and respond to their environment under unconstrained and ecologically natural conditions. SIGNIFICANCE: Eye tracking in HD patients revealed saccadic, pupil, and blink abnormalities in early HD patients, suggestive of brain circuitry abnormalities that probably involve brain stem deficits. Further research should explore the impact of these changes on the quality of life of the patients affected by the disease.

Pistol shooting performance under pressure: Longitudinal changes in gaze behavior of male and female Army cadets.

We found evidence that Army cadets improved their gaze behavior and performance across time under high and low pressure in a shooting task. The purpose of the study was to determine if male and female cadets developed an optimal quiet eye (QE) onset, a longer QE duration, and decreased pupil diameter variability (PDV) over time under low (LP) and high pressure (HP) conditions. The study was carried out over four sessions, with intervals of 4.5 months. During each session, 16 men and 12 women, first-year cadets of The Brazilian Army Academy, performed ten pistol shots under counterbalanced LP and HP conditions. The cadets shot in the upright position and wore an eye-tracker. Shooting accuracy improved and did not differ for men and women in the LP condition, however during HP the women performed more poorly than the men in session 1 but improved to a level similar to the men in session 4. QE duration Pre (aiming) did not differ during LP, while during HP QE Post (execution) increased across the session for men and women. QE onset 2 (execution) occurred earlier for the men than women during LP, while during HP the women improved to a level similar to the men in sessions 3 and 4. PDV declined across sessions for men and women with the lowest values in sessions 3 and 4. The findings are discussed within social facilitation theory, which states the context of training affects the rate at which improvements in motor skills occur. The results show that women cadets can improve their shooting performance, quiet eye duration, quiet eye onset and pupil diameter variability to a level similar to men if three to four LP and HP training sessions are scheduled across approximately 12-18 months.

Quantitative Pupillometry for Intracranial Pressure (ICP) Monitoring in Traumatic Brain Injury: A Scoping Review.

The neurological examination has remained key for the detection of worsening in neurocritical care patients, particularly after traumatic brain injury (TBI). New-onset, unreactive anisocoria frequently occurs in such situations, triggering aggressive diagnostic and therapeutic measures to address life-threatening elevations in intracranial pressure (ICP). As such, the field needs objective, unbiased, portable, and reliable methods for quickly assessing such pupillary changes. In this area, quantitative pupillometry (QP) proves promising, leveraging the analysis of different pupillary variables to indirectly estimate ICP. Thus, this scoping review seeks to describe the existing evidence for the use of QP in estimating ICP in adult patients with TBI as compared with invasive methods, which are considered the standard practice. This review was conducted in accordance with the Joanna Briggs Institute methodology for scoping reviews, with a main search of PubMed and EMBASE. The search was limited to studies of adult patients with TBI published in any language between 2012 and 2022. Eight studies were included for analysis, with the vast majority being prospective studies conducted in high-income countries. Among QP variables, serial rather than isolated measurements of neurologic pupillary index, constriction velocity, and maximal constriction velocity demonstrated the best correlation with invasive ICP measurement values, particularly in predicting refractory intracranial hypertension. Neurologic pupillary index and ICP also showed an inverse relationship when trends were simultaneously compared. As such, QP, when used repetitively, seems to be a promising tool for noninvasive ICP monitoring in patients with TBI, especially when used in conjunction with other clinical and neuromonitoring data.

Pupil size change in agricultural workers exposed to pesticides.

CLINICAL RELEVANCE: Pupil size evaluation using clinical examination may be important for detecting and monitoring individuals at risk of neurotoxic effects from chemical exposure, as it may enable early intervention and the implementation of preventive measures. BACKGROUND: This work aimed to investigate the association between pesticide exposure and pupil size. Pupil size is regulated by muscarinic and nicotinic receptors, and it is well-established that common pesticide chemicals disrupt this regulation. METHODS: Twenty agricultural workers exposed to pesticides, and twenty participants not exposed, underwent visual screening, and pupil size evaluation under mesopic and photopic conditions. Additionally, signs of neurotoxicity and pesticide exposure in both groups were evaluated using the modified version of the neurotoxic symptoms questionnaire (Q16) and measuring cholinesterase (AChE) levels in blood, respectively. RESULTS: Agricultural workers exposed to pesticides had a score indicating medium-high level of neurotoxicity (49.85 (SD ± 8.94)) which was significantly higher (t (36) = 7.659, p ≤ 0.0001) than non-exposed participants who had low levels of neurotoxicity (27.25 SD ± 8.86). There was a significant difference in pupil size (mm) under mesopic (t (19) 4.42 p = 0.003) and scotopic (t (19) 4.63, p = 0.0002) conditions between the two groups. Additionally, there was a significant difference in AChE blood levels (t (19) 2.94 p = 0.008) between exposed and non-exposed participants, indicating that exposed workers had low levels of this enzyme (average exposed group 3381 U/L (SD ± 1306)) compared to the non-exposed group (average non-exposed group 4765 U/L (SD ± 1300)). A significant negative correlation between AChE levels, years of exposure, and pupil size was found. The latter finding importantly showed that smaller pupils are associated with the accumulation of acetylcholine or a decrease in the activity of the enzyme AChE. CONCLUSION: Pupil size of agricultural workers exposed to pesticides can be abnormal and is associated with neurotoxicity as indicated by symptomatology and cholinesterase levels. Evaluation of pupil size may be useful for clinically detecting neurotoxicity.

Bilateral tonic pupil during a migraine attack: a case report / Pupila tônica bilateral durante crise de enxaqueca: relato de caso

INTRODUCTION:Tonic pupil or Adie's pupil occurs due to parasympathetic denervation, and it is characterized by mydriasis with little or no response to light, with pupillary contraction to accommodation. It is caused by eye pathologies, such as infections, trauma, neoplasms, inflammatory diseases, and systemic diseases with autonomic dysfunction. Few cases have been reported of bilateral tonic pupils associated with migraine attacks. CASE REPORT: Our aimed to describe the case of a young female patient with a history of chronic migraine without aura, who presented acutely with bilateral pupillary mydriasis during a migraine attack, characterized as tonic pupil, and to discuss the possible causes of mydriasis during a migraine attack.

INTRODUÇÃO: A pupila tônica ou pupila de Adie ocorre devido à denervação parassimpática e é caracterizada por midríase com pouca ou nenhuma resposta à luz, com contração pupilar à acomodação. É causada por patologias oculares, como infecções, traumas, neoplasias, doenças inflamatórias e doenças sistêmicas com disfunção autonômica. Poucos casos foram relatados de pupilas tônicas bilaterais associadas a crises de enxaqueca. RELATO DE CASO: Nosso objetivo foi descrever o caso de uma paciente jovem, com história de enxaqueca crônica sem aura, que apresentou agudamente midríase pupilar bilateral durante uma crise de enxaqueca, caracterizada como pupila tônica, e discutir as possíveis causas da midríase durante uma crise de enxaqueca. ataque de enxaqueca.

Pupil dilation evaluation of two mydriatic dosing profiles delivered by the Optejet®.

Aim: To compare pupil dilation achieved by a single microdose versus two microdoses of tropicamide-phenylephrine fixed combination (TR-PH FC) delivered by the Optejet®. Patients & methods: In this assessor-masked, crossover, noninferiority study, 60 volunteers underwent two treatment visits and received either one (∼8 µl) or two sprays (∼16 µl) of TR-PH FC to both eyes in randomly assigned order. Results: At 35 min postdose, mean change in pupil diameter was 4.6 mm and 4.9 mm following one or two sprays, respectively. The estimated treatment group difference was -0.249 mm (standard error: 0.036; 95% CI: -0.320, -0.177). No adverse events were reported. Conclusion: A single microdose was noninferior to two microdoses of TR-PH FC and achieved clinically significant mydriasis in a timely manner. Clinical Trial Registration: NCT04907474 (ClinicalTrials.gov).

Pupil dilation efficacy and efficiency were evaluated using microdosing via the Optejet^®. The Optejet^® is a new ophthalmologic drug device that utilizes piezoelectric technology to deliver a fine, controlled, horizontal microdroplet spray with precise volume (∼8 µl), spray pattern and velocity. A single spray versus two sprays of tropicamide-phenylephrine fixed combination (TR-PH FC) were administered to both eyes anesthetic free. Efficacy and safety were evaluated at specific time intervals. The primary end point was the mean change in pupil diameter at 35 min compared with baseline. At 35 min, clinically relevant dilation was observed, with a mean change of 4.55 mm ± 0.68 for one spray and 4.88 ± 0.60 for two sprays. The treatment group difference of one spray of TR-PH FC was noninferior to two sprays (p < 0.001). Rapid dilation was observed at 15 min, and the proportions of eyes that achieved a pupil diameter of ≥6.0 mm were 74% and 83% of patients at 15 min with one spray and two sprays, respectively. The mydriatic agent was well tolerated with the delivery system even in the absence of topical anesthetic, with no ocular or system adverse events reported. Mydriasis is a vital component of routine eye healthcare, and the current standard-of-care mydriatic eye drops potentially have limitations, including contamination, spillage and burning/stinging. Delivery of a mydriatic with the Optejet^® may improve patient care flow in the clinical office setting.

Glasgow coma scale pupil score (GCS-P) and the hospital mortality in severe traumatic brain injury: analysis of 1,066 Brazilian patients.

BACKGROUND: Pupil reactivity and the Glasgow Coma Scale (GCS) score are the most clinically relevant information to predict the survival of traumatic brain injury (TBI) patients. OBJECTIVE: We evaluated the accuracy of the GCS-Pupil score (GCS-P) as a prognostic index to predict hospital mortality in Brazilian patients with severe TBI and compare it with a model combining GCS and pupil response with additional clinical and radiological prognostic factors. METHODS: Data from 1,066 patients with severe TBI from 5 prospective studies were analyzed. We determined the association between hospital mortality and the combination of GCS, pupil reactivity, age, glucose levels, cranial computed tomography (CT), or the GCS-P score by multivariate binary logistic regression. RESULTS: Eighty-five percent (n = 908) of patients were men. The mean age was 35 years old, and the overall hospital mortality was 32.8%. The area under the receiver operating characteristic curve (AUROC) was 0.73 (0.70-0.77) for the model using the GCS-P score and 0.80 (0.77-0.83) for the model including clinical and radiological variables. The GCS-P score showed similar accuracy in predicting the mortality reported for the patients with severe TBI derived from the International Mission for Prognosis and Clinical Trials in TBI (IMPACT) and the Corticosteroid Randomization After Significant Head Injury (CRASH) studies. CONCLUSION: Our results support the external validation of the GCS-P to predict hospital mortality following a severe TBI. The predictive value of the GCS-P for long-term mortality, functional, and neuropsychiatric outcomes in Brazilian patients with mild, moderate, and severe TBI deserves further investigation.

ANTECEDENTES: A reatividade pupilar e o escore da Escala de Coma de Glasgow (ECG) representam as informações clínicas mais relevantes para predizer a sobrevivência de pacientes com traumatismo cranioencefálico (TCE). OBJETIVO: Avaliar a acurácia da ECG com resposta pupilar (ECG-P) como índice prognóstico para predizer mortalidade hospitalar em pacientes brasileiros acometidos por TCE grave e compará-lo com um modelo combinando ECG e resposta pupilar com fatores prognósticos radiológicos. MéTODOS: Foram analisados dados de 1.066 pacientes com TCE grave de 5 estudos prospectivos. Foi determinada a associação entre mortalidade hospitalar e a combinação de ECG, reatividade pupilar, idade, níveis glicêmicos, tomografia computadorizada (TC) de crânio ou o escore ECG-P por regressão logística binária multivariada. RESULTADOS: Oitenta e cinco por cento (n = 908) dos pacientes eram homens. A média de idade foi de 35 anos e a mortalidade hospitalar geral foi de 32,8%. A AUROC (em português, Curva Característica de Operação do Receptor) foi de 0,73 (0,70­0,77) para o modelo utilizando o escore ECG-P e de 0,80 (0,77­0,83) para o modelo incluindo variáveis clínicas e radiológicas. O escore ECG-P mostrou acurácia semelhante na previsão da mortalidade relatada para pacientes com TCE grave derivados dos estudos International Mission for Prognosis and Clinical Trials in TBI (IMPACT, na sigla em inglês) e Corticosteroid Randomization After Significant Head Injury (CRASH, na sigla em inglês). CONCLUSãO: Nossos resultados apoiam a validação externa da ECG-P para prever a mortalidade hospitalar após um TCE grave. O valor preditivo da ECG-P para mortalidade a longo prazo, resultados funcionais e neuropsiquiátricos em pacientes brasileiros com TCE leve, moderado e grave precisam ser investigados.

Do executive function performance, gaze behavior, and pupil size change during incremental acute physical exercise?

Several studies have investigated the interaction between acute physical exercise and cognitive performance. However, few studies have investigated this issue during acute high-intensity exercise. In the present study, we evaluated executive functions (EFs) during incremental exercise in three different intensities [below lactate threshold (LT), at LT, and above LT], measuring EFs performance, gaze behavior, and pupil diameter. Twenty subjects were familiarized with the EFs test and participated in a graded maximal exercise test on a cycle ergometer on the first visit. On the second visit, they performed the EFs task at rest and while exercising at three different intensities using mobile eye-tracking glasses. Our results showed that the psychophysiological measures differed between the conditions. Regarding EFs performance, during exercise above LT, the subjects showed worse accuracy when compared with rest (p < .001) and below LT (p < .001). In addition, the response time (RT) at LT and above LT was shorter than in the rest condition (p < .050). Further, RT was faster (p = .002) in the above LT than in the below LT condition. In addition, the gaze behavior measures indicated that exercise, independently of the intensity, improves the number of fixations with shorter fixation durations compared to the rest condition (p < .050). Additionally, we found no significant differences in average and peak pupil diameter between conditions. In conclusion, exercise at LT improves the EFs performance while exercising above LT worsens EFs performance. However, there were no significant differences in average and peak pupil diameter between conditions.

Classifying the difficulty levels of working memory tasks by using pupillary response.

Knowing the difficulty of a given task is crucial for improving the learning outcomes. This paper studies the difficulty level classification of memorization tasks from pupillary response data. Developing a difficulty level classifier from pupil size features is challenging because of the inter-subject variability of pupil responses. Eye-tracking data used in this study was collected while students solved different memorization tasks divided as low-, medium-, and high-level. Statistical analysis shows that values of pupillometric features (as peak dilation, pupil diameter change, and suchlike) differ significantly for different difficulty levels. We used a wrapper method to select the pupillometric features that work the best for the most common classifiers; Support Vector Machine (SVM), Decision Tree (DT), Linear Discriminant Analysis (LDA), and Random Forest (RF). Despite the statistical difference, experiments showed that a random forest classifier trained with five features obtained the best F1-score (82%). This result is essential because it describes a method to evaluate the cognitive load of a subject performing a task using only pupil size features.

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.

Poder dióptrico del lente intraocular y dilatación en pacientes con catarata / Dioptric power of intraocular lens and dilatation in patients with cataract

ntroducción: la cirugía de catarata con implante de un lente intraocular es, hoy en día, el procedimiento quirúrgico más frecuente en todo el mundo. Su éxito depende de muchos factores, uno de los más importantes es el cálculo exacto del poder dióptrico del lente intraocular. Objetivo: comparar el cálculo del poder dióptrico del lente intraocular en los pacientes sin y con dilatación pupilar. Material y métodos: estudio longitudinal, en el que se determinó el cálculo del poder dióptrico del lente intraocular en pacientes con y sin dilatación pupilar. Las variables de estudio fueron: edad, género, ojo a estudiar, queratometría, longitud axial, profundidad de cámara anterior y poder dióptrico del lente intraocular. Se realizó estadística descriptiva y t de Student. Resultados: se estudiaron 37 pacientes, 23 mujeres y 14 hombres. La edad promedio fue de 68 ± 7.87 años. Se estudiaron 64 ojos, 30 fueron derechos y 34 izquierdos. Estadísticamente solo hubo diferencia significativa en K2 de la biometría ocular entre pacientes sin y con dilatación pupilar al obtenerse un valor de p ≤ 0.05. Conclusión: no existen cambios en el cálculo del poder dióptrico del LIO sin y con dilatación pupilar.

Background: Cataract surgery with intraocular lens implant is, nowadays, the most frequent surgical procedure in all the world. Its success depends on a lot of factors, one of the most important is the calculation of the exact dioptric power of intraocular lens. Objective: To compare the calculation of dioptric power of intraocular lens with and without dilatation in patients with cataract. Material and methods: Longitudinal study, the calculation of the dioptric power of the intraocular lens was determined in patients without and with pupillary dilation. The variables were age, gender, eye to study, keratometry, axial length, anterior chamber depth and dioptric power of the intraocular lens. Descriptive statistics and Student t test were performed. Results: There were 37 patients, 23 females and 14 males. The average age was 68 + 7.87 years. Sixty-four eyes were studied, 30 were right and 34 left. Statistically, there was only significant difference in K2 of the ocular biometry between patients without and with pupillary dilation when obtaining a value of p < 0.05. Conclusion: There are no changes in the calculation of the dioptric power of the Intraocular lens without and with pupillary dilation

Characteristics of Higher-Order Aberrations in Different Stages of Keratoconus.

OBJECTIVES: To characterize higher-order aberrations (HOAs) in clinical and subclinical keratoconus (KC). METHODS: The study included 33, 36, and 26 patients with clinical, topographic (no clinical signs), and pretopographic (normal topography and no clinical signs) KC and 30 controls. Ocular and corneal HOAs for the 4-mm pupils were measured using a wavefront sensor and expanded up to the sixth order of Zernike polynomials. The magnitudes of trefoil, coma, tetrafoil, secondary astigmatism, and spherical aberration were calculated via Zernike vector analysis and used as HOA parameters along with total HOAs. Area under the receiver operating characteristic curve (AUROC) values for each wavefront parameter for pretopographic KC were compared. RESULTS: Control eyes and eyes with pretopographic KC had significantly lower ocular or corneal total HOAs and Zernike vector terms than those with clinical KC and topographic KC, except for ocular tetrafoil between topographic KC and pretopographic KC and spherical aberration among all groups. The AUROCs for corneal total HOAs and corneal coma for pretopographic KC and control eyes were 0.781 (100% sensitivity and 47% specificity) and 0.735 (73% sensitivity and 73% specificity), respectively. CONCLUSION: Corneal total HOAs and corneal coma exhibited a potential ability to discriminate pretopographic KC from normal control eyes.

Femtosecond laser-assisted cataract surgery in small pupils using non-aligned iris expansion ring without viscoelastic and corneal suture.

PURPOSE: To describe a technique for cataract surgery in eyes with small pupils that combines the use of the femtosecond laser and an iris expansion device, but without the use of corneal sutures and an ophthalmic viscosurgical device (OVD) at the time of laser application. METHODS: A retrospective case series of three eyes with small pupils were operated by the same surgeon without a corneal suture and with removal of anterior chamber OVD prior to laser application. RESULTS: Corrected distance visual acuity (CDVA) for 1 eye in a 70 year-old patient was 20/70 preoperatively and 20/20 thirty days postoperatively. CDVA for a second patient was 20/50 and 20/200 in the two eyes, which improved to 20/25 two months postoperatively in both eyes. There were no complications observed and the intraocular lens were well-centered. CONCLUSION: The use of mechanical pupil expander rings is safe and practical in setting small pupils during femtosecond laser-assisted cataract surgery.

Effect of pupil dilation on intraocular pressure in preterm and term infants.

PURPOSE: To evaluate the effect of pupil dilation on intraocular pressure in preterm and term newborns. METHODS: This prospective study involved 55 eyes of 28 preterm infants and 38 eyes of 20 term infants. The infants were divided into two groups according to their gestational ages at birth as follows: preterm group, <37 weeks and term group, ≥37 weeks. Pupil dilation was attained with tropicamide 0.5% and phenylephrine 2.5%. Intraocular pressure measurements were performed with Icare PRO (Icare Finland Oy, Helsinki, Finland) before and after pupil dilation. A paired t test was used to compare the measurements before and after pupil dilation. RESULTS: The mean intraocular pressure change was -1.04 ± 3.03 mmHg (6.20/-11.40 mmHg) in the preterm group and -0.39 ± 2.81 mmHg (4.60/-9.70 mmHg) in the term group. A statistically significant difference in intraocular pressure was observed only in the preterm group after pupil dilation (p=0.01). CONCLUSION: An unexpected alteration in intraocular pressure in newborns may occur after pupil dilation, especially in preterm infants.

Pupilometría óptica cuantitativa en cuidados intensivos / Quantitative optical pupillometry in intensive care unit

Neurological examination is still one of the most important semiological aspects in the daily assessment of the critically ill patient, especially in those with acute neurological injury. Within the neurological examination, the pupillary examination, including size, symmetry, and reactivity to light stimulus, is one of the most fundamental aspects and with the greatest weight when it comes to predict the neurological outcome[]. Conventional pupillary assessment is based on a qualitative, subjective, explorer- dependent method, with great inter-explorer variability and therefore, subject to errors during its performance and interpretation[]. In the modern era, the incorporation of new technologies in the field of critically ill patients has made us focus more on a personalized and more precise medicine, leaving behind the traditional examination practices to be replaced by diagnostic tools that facilitate work and overcome the human factor of the equation, thanks to the quantitative optical pupillometry (POC) by infrared.

La exploración neurológica sigue siendo uno de los aspectos semiológicos más importantes en la evaluación rutinaria del enfermo crítico, sobre todo en pacientes con patología aguda neurológica. Dentro de la exploración neurológica, el examen pupilar, incluyendo el tamaño, simetría y la reactividad pupilar a la luz, es uno de los aspectos más fundamentales y con mayor peso a la hora de predecir trastornos neurológicos agudos, e incluso para predecir el pronóstico neurológico[]. La exploración pupilar convencional se basa en un método cualitativo, subjetivo, explorador dependiente, con gran variabilidad interexplorador y, por lo tanto, sujeto a errores durante su realización e interpretación[]. En la era moderna, la incorporación de nuevas tecnologías en el ámbito del paciente crítico, han hecho que nos enfoquemos más en una medicina personalizada y más precisa, dejando relegadas las prácticas de exploración tradicionales para ser sustituidas por herramientas diagnósticas que facilitan el trabajo y eliminan el factor humano de la ecuación, entre estas se encuentra la pupilometría óptica cuantitativa (POC) por infrarrojos.

Identificação da velocidade anormal da dilatação de pupila como biomarcador de lesão cerebral em pacientes neurocríticos / Identification of abnormal pupil dilation velocity as a biomarker of cerebral injury in neurocritically ill patients

RESUMO Objetivo: Calcular as velocidades médias da dilatação de pupila para classificar a gravidade da lesão derivada da escala de coma de Glasgow, estratificada por variáveis de confusão. Métodos: Neste estudo, analisaram-se 68.813 exames das pupilas para determinar a velocidade normal de dilatação em 3.595 pacientes com lesão cerebral leve (13 - 15), moderada (9 - 12) ou grave (3 - 8), segundo a escala de coma de Glasgow. As variáveis idade, sexo, raça, tamanho da pupila, tempo de permanência na unidade de terapia intensiva, pressão intracraniana, uso de narcóticos, classificação pela escala de coma de Glasgow e diagnóstico foram consideradas confundidoras e controladas para análise estatística. Empregou-se regressão logística com base em algoritmo de classificação com aprendizado de máquina para identificar os pontos de corte da velocidade de dilatação para as categorias segundo a escala de coma de Glasgow. Resultados: As razões de chance e os intervalos de confiança desses fatores se mostraram estatisticamente significantes em sua influência sobre a velocidade de dilatação. A classificação com base na área sob a curva mostrou que, para o grau leve, na escala de coma de Glasgow, o limite da velocidade de dilatação foi de 1,2mm/s, com taxas de falsa probabilidade de 0,1602 e 0,1902 e áreas sob a curva de 0,8380 e 0,8080, respectivamente, para os olhos esquerdo e direito. Para grau moderado na escala de coma de Glasgow, a velocidade de dilatação foi de 1,1mm/s com taxas de falsa probabilidade de 0,1880 e 0,1940 e áreas sob a curva de 0,8120 e 0,8060, respectivamente, nos olhos esquerdo e direito. Mais ainda, para o grau grave na escala de coma de Glasgow, a velocidade de dilatação foi de 0,9mm/s, com taxas de falsa probabilidade de 0,1980 e 0,2060 e áreas sob a curva de 0,8020 e 0,7940, respectivamente, nos olhos esquerdo e direito. Esses valores foram diferentes dos métodos prévios de descrição subjetiva e das velocidades de dilatação previamente estimadas. Conclusão: Observaram-se velocidades mais lentas de dilatação pupilar em pacientes com escores mais baixos na escala de coma de Glasgow, indicando que diminuição da velocidade pode indicar grau mais grave de lesão neuronal.

ABSTRACT Objective: To calculate mean dilation velocities for Glasgow coma scale-derived injury severity classifications stratified by multiple confounding variables. Methods: In this study, we examined 68,813 pupil readings from 3,595 patients to determine normal dilation velocity with brain injury categorized based upon a Glasgow coma scale as mild (13 - 15), moderate (9 - 12), or severe (3 - 8). The variables age, sex, race, pupil size, intensive care unit length of stay, intracranial pressure, use of narcotics, Glasgow coma scale, and diagnosis were considered as confounding and controlled for in statistical analysis. Machine learning classification algorithm-based logistic regression was employed to identify dilation velocity cutoffs for Glasgow coma scale categories. Results: The odds ratios and confidence intervals of these factors were shown to be statistically significant in their influence on dilation velocity. Classification based on the area under the curve showed that for the mild Glasgow coma scale, the dilation velocity threshold value was 1.2mm/s, with false probability rates of 0.1602 and 0.1902 and areas under the curve of 0.8380 and 0.8080 in the left and right eyes, respectively. For the moderate Glasgow coma scale, the dilation velocity was 1.1mm/s, with false probability rates of 0.1880 and 0.1940 and areas under the curve of 0.8120 and 0.8060 in the left and right eyes, respectively. Furthermore, for the severe Glasgow coma scale, the dilation velocity was 0.9mm/s, with false probability rates of 0.1980 and 0.2060 and areas under the curve of 0.8020 and 0.7940 in the left and right eyes, respectively. These values were different from the previous method of subjective description and from previously estimated normal dilation velocities. Conclusion: Slower dilation velocities were observed in patients with lower Glasgow coma scores, indicating that decreasing velocities may indicate a higher degree of neuronal injury.

A closer look at pupil diversity and evolution in frogs and toads.

The eyes of frogs and toads (Anura) are among their most fascinating features. Although several pupil shapes have been described, the diversity, evolution, and functional role of the pupil in anurans have received little attention. Studying photographs of more than 3200 species, we surveyed pupil diversity, described their morphological variation, tested correlation with adult habits and diel activity, and discuss major evolutionary patterns considering iris anatomy and visual ecology. Our results indicate that the pupil in anurans is a highly plastic structure, with seven main pupil shapes that evolved at least 116 times during the history of the group. We found no significant correlation between pupil shape, adult habits, and diel activity, with the exception of the circular pupil and aquatic habits. The vertical pupil arose at least in the most-recent common ancestor of Anura + Caudata, and this morphology is present in most early-diverging anuran clades. Subsequently, a horizontal pupil, a very uncommon shape in vertebrates, evolved in most neobatrachian frogs. This shape evolved into most other known pupil shapes, but it persisted in a large number of species with diverse life histories, habits, and diel activity patterns, demonstrating a remarkable functional and ecological versatility.

Influence of pupillary dynamics on the defocus curve of eyes implanted with diffractive multifocal lenses: a randomized study / Influência da dinâmica pupilar na curva de desfoco de olhos implantados com lentes multifocais difrativas: um estudo randomizado

ABSTRACT Purpose: To evaluate the influence of pupil dynamics on the defocus profile and area-of-focus of eyes implanted with a diffractive multifocal intraocular lens (IOL). Methods: This prospective randomized trial was conducted at the Department of Ophthalmology, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil. Thirty-eight patients were randomly assigned to receive the multifocal SN6AD1 (n=20) or the aspheric monofocal SN60WF (aIOL) (n=18) IOLs bilaterally. Dynamic pupillometry, visual acuity for distance and near, corrected and uncorrected, and a defocus profile were assessed postoperatively. The area-of-focus was calculated using an empirical polynomial model of the defocus profile. Results: Sixteen patients (32 eyes) in the multifocal SN6AD1 group and 17 patients (34 eyes) in the aspheric monofocal SN60WF group completed the 1-year follow-up. There were no significant between-group differences in monocular uncorrected distance or near visual acuity. The defocus profiles of the mfIOL group showed a double peak, whereas those of the aspheric monofocal SN60WF group showed only one peak, which is typical for a monofocal intraocular lens. The area-of-focus of the aIOL group (4.66 ± 1.51 logMARxD) was significantly different from that of the multifocal SN6AD1 (1.99 ± 1.31 logMARxD). Pupil size at maximum contraction after exposure to a flash of 30 cd/m2 for 1 second was significantly correlated with a better area-of-focus in the multifocal SN6AD1 group (r=0.54; p=0.0017), whereas this was not the case in the aspheric monofocal SN60WF group. Conclusion: These findings indicate that in eyes implanted with an multifocal SN6AD1, the smaller the pupil size, the better is the area-of-focus and hence the better is the visual performance. This correlation was not found for the aspheric monofocal SN60WF.(AU)

RESUMO Objetivo: Avaliar a influência da dinâmica pupilar na curva de desfoco de olhos implantados com lente intraoculares multifocais difrativas. Métodos: Estudo prospectivo e randomizado realizado na Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo - Departamento de Oftalmologia. Trinta e oito pacientes foram aleatoriamente designados para receber bilateralmente lentes intraoculares SN6AD1 (n=20) (mfIOL) ou SN60WF (n=18) (aIOL). Além da acuidade visual para longe e perto, corrigida e não corrigida, e curva de desfoco, foi ainda realizada pupilometria dinâmica. A área sob a curva de desfoco foi calculada usando um modelo polinomial empírico. Resultados: Um total de 16 e 17 pacientes (n=32 e 34 olhos) completaram 1 ano de seguimento nos grupos mfIOL e aIOL, respectivamente. Não houve diferenças significativas entre grupos para as acuidades visuais seja para longe ou perto. As curvas de desfoco do grupo mfIOL mostraram um pico duplo; enquanto o SN60WF mostrou apenas um pico, típico para uma lente intraoculares monofocal. A média da área sob a curva de desfoco do grupo aIOL foi (4,66 ± 1,51 logMAR.dp), e essa é estatisticamente significante diferente da métrica do grupo mfIOL (1,99 ± 1,31 logMAR.dp). A pupila na contração máxima após a exposição a um flash de 30 cd/m2 por 1 segundo foi significativamente correlacionada com uma melhor área de foco no grupo mfIOL (r=0,54; p=0,0017), essa relação não foi observada para o grupo aIOL. Conclusão: Estes dados indicam que quanto menor a pupila durante contração, melhor é a área sob a curva de desfoco e, portanto, o desempenho visual dos olhos implantados com essa mfIOL. Esta correlação não foi encontrada para lentes intraoculares monofocais.(AU)