Pupillary Reaction Research Articles

250 Advanced management of out of hospital cardiac arrest: a single-centre experience in a tertiary cardiac intensive care unit

Abstract Aims Out-of-hospital cardiac arrest (OHCA) affects around 1/1000 person-years. Following return of spontaneous circulation (ROSC), the patient can manifest neurological impairment. A targeted temperature management (TTM) protocol is recommended to prevent hypoxic–ischaemic brain damage in patients with coma after cardiac arrest. Neuro-prognostication remains substantial for the prediction of clinical outcomes. To study clinical characteristics, overall survival, and neurological outcome of patients with Glasgow Coma Scale (GCS) <8 after ROSC following an OHCA of presumed cardiac cause at our Institution. Secondly, to investigate determinants of a negative neurological outcome. Methods Observational retrospective study evaluating all patients with OHCA of presumed cardiac cause and with GCS < 8 after ROSC treated in an intensive cardiac care unit of a tertiary centre. The study period was from January 2017 to December 2020. Results One-hundred and five patients out of 107 patients initially selected were included in the study (77% male, mean age 67 years). At 30 days, mortality was 41% and 53% of patients had a poor neurological outcome (Cerebral Performance Category, CPC, 3–5). Sixty-nine patients (66%) underwent TTM. In regard of the circumstances of OHCA, index event in a private place [OR = 3.12 (1.43–7.11), P = 0.005], ineffective rhythm changes during resuscitation manoeuvres [OR = 2.40 (1.05–5.47), P = 0.037] and a greater amount of adrenaline administered during resuscitation [OR = 1.62 (1.27–2.06), P < 0.001] were related to a worse neurological outcome. A history of diabetes mellitus [OR = 3.35 (1.26–8.91), P = 0.015], blood lactates at presentation [OR = 1.33 (1.15—1.53), P < 0.001], neuron-specific enolase (NSE) at presentation [OR = 1.055 (1.022–1.089), P < 0.001] and as peak [OR = 1.034 (1.013–1.054), P < 0.001] were associated with a worse neurological outcome. Among the neurological examinations, the presence of status epilepticus on the EEG [OR = 13.97 (1.73–113.02), P = 0.013] was a predictor of a poor neurological outcome. Treatment with targeted temperature management did not show a significant impact in terms of outcome at univariate analysis [OR = 1.226 (0.547–2.748), P = 0.62]. Two models were developed with multivariate logistic regression for the prediction of neurological outcome. The first one, on a statistical basis, considers pupil reactivity after ROSC, NSE as peak and left ventricular ejection fraction (AUC = 92%). The second model, on a clinical basis, considers age, first blood lactate value and NSE as peak (AUC = 89 %). Finally, the performance of the multiparametric MIRACLE score was tested in our population (AUC 0.81 for neurological outcome at 30 days). Conclusions In our population, at 30 days after cardiac arrest, survival rate and the rate of good neurological outcome were comparable to those of the major international registries and studies. Even though patients treated with TTM did not demonstrate significant differences in terms of neurological outcome, this might be related to study-sample size and patient selection. Results in the literature are still controversial on this topic. The MIRACLE score showed a good performance, making it suitable for clinical use in our population. Similarly, the proposed multivariate models are potentially useful for the elaboration of simple and effective prognostic scores in neurological risk stratification.

Experimental methods of pupillographic analysis based on high-speed video recording devices

The prospects for using artificial intelligence in video analytics are becoming more and more undeniable. Researchers are actively working on methods for making decisions based on the results of automated analysis of the sequence of images received from video cameras. The purpose of our study was to develop a method for decision-making based on modeling a person's pupillary response to an information stimulus. A ZWO ASI120MC digital video camera was used for research. The studies carried out made it possible to reliably establish that the state of the optical system of the eye when viewing the calibration slide comes to a physical state common to all people. This made it possible to systematize the pupillograms, referring them to one of two categories (stress state is / is not). Having determined an individual threshold value during calibration, it becomes possible to quickly classify a person's emotional response to the received information impulse. Based on the developed methodology for systematizing the pupillary reaction to an information stimulus by categories, a decision tree for intelligent video surveillance systems was built. In addition to the size of the pupils, the algorithm takes into account the parameters of gaze fixation on stimulus images, the stability of the illumination of the surface of the pupils.

A machine learning model for predicting favorable outcome in severe traumatic brain injury patients after 6 months.

BackgroundTraumatic brain injury (TBI), which occurs commonly worldwide, is among the more costly of health and socioeconomic problems. Accurate prediction of favorable outcomes in severe TBI patients could assist with optimizing treatment procedures, predicting clinical outcomes, and result in substantial economic savings.MethodsIn this study, we examined the capability of a machine learning-based model in predicting “favorable” or “unfavorable” outcomes after 6 months in severe TBI patients using only parameters measured on admission. Three models were developed using logistic regression, random forest, and support vector machines trained on parameters recorded from 2,381 severe TBI patients admitted to the neuro-intensive care unit of Rajaee (Emtiaz) Hospital (Shiraz, Iran) between 2015 and 2017. Model performance was evaluated using three indices: sensitivity, specificity, and accuracy. A ten-fold cross-validation method was used to estimate these indices.ResultsOverall, the developed models showed excellent performance with the area under the curve around 0.81, sensitivity and specificity of around 0.78. The top-three factors important in predicting 6-month post-trauma survival status in TBI patients are “Glasgow coma scale motor response,” “pupillary reactivity,” and “age.”ConclusionsMachine learning techniques might be used to predict the 6-month outcome in TBI patients using only the parameters measured on admission when the machine learning is trained using a large data set.

All that meets the eye: The contribution of reward processing and pupil mimicry on pupillary reactions to facial trustworthiness

The present work investigates pupillary reactions induced by exposure to faces with different levels of trustworthiness. Participants’ (N = 69) pupillary changes were recorded while they viewed white male faces with a neutral expression varying on facial trustworthiness. Results suggest that reward processing and pupil mimicry are relevant mechanisms driving participants’ pupil reactions. However, when including both factors in one statistical model, pupil mimicry seems to be a stronger predictor than reward processing of participants’ pupil dilation. Results are discussed in light of pupillometry evidence.

Automatic detection of pupil reactions in cataract surgery videos.

In the light of an increased use of premium intraocular lenses (IOL), such as EDOF IOLs, multifocal IOLs or toric IOLs even minor intraoperative complications such as decentrations or an IOL tilt, will hamper the visual performance of these IOLs. Thus, the post-operative analysis of cataract surgeries to detect even minor intraoperative deviations that might explain a lack of a post-operative success becomes more and more important. Up-to-now surgical videos are evaluated by just looking at a very limited number of intraoperative data sets, or as done in studies evaluating the pupil changes that occur during surgeries, in a small number intraoperative picture only. A continuous measurement of pupil changes over the whole surgery, that would achieve clinically more relevant data, has not yet been described. Therefore, the automatic retrieval of such events may be a great support for a post-operative analysis. This would be especially true if large data files could be evaluated automatically. In this work, we automatically detect pupil reactions in cataract surgery videos. We employ a Mask R-CNN architecture as a segmentation algorithm to segment the pupil and iris with pixel-based accuracy and then track their sizes across the entire video. We can detect pupil reactions with a harmonic mean (H) of Recall, Precision, and Ground Truth Coverage Rate (GTCR) of 60.9% and average prediction length (PL) of 18.93 seconds. However, we consider the best configuration for practical use the one with the H value of 59.4% and PL of 10.2 seconds, which is much shorter. We further investigate the generalization ability of this method on a slightly different dataset without retraining the model. In this evaluation, we achieve the H value of 49.3% with the PL of 18.15 seconds.

Boy With Visual Loss

A 7-year-old boy presented to the emergency department for 3 days of painless monocular vision loss of the left eye following minor trauma to the eye by a stick 3 weeks prior. Examination of the left eye was notable for a sluggishly reactive pupil, leukocoria, and visual acuity less than 20/200 (Figure 1), whereas the right eye was normal.

Predictors of Mortality, Withdrawal of Life-Sustaining Measures, and Discharge Disposition in Octogenarians with Subdural Hematomas

Risk factors for mortality in patients with subdural hematoma (SDH) include poor Glasgow Coma Scale (GCS) score, pupil nonreactivity, and hemodynamic instability on presentation. Little is published regarding prognosticators of SDH in the elderly. This study aims to examine risk factors for hospital mortality and withdrawal of life-sustaining measures in an octogenarian population presenting with SDH. A prospectively collected multicenter database of 3279 traumatic brain injury admissions to 45 different U.S. trauma centers between 2017 and 2019 was queried to identify patients aged >79 years old presenting with SDH. Factors collected included baseline demographic data, past medical history, antiplatelet/anticoagulant use, and clinical presentation (GCS, pupil reactivity, injury severity scale [ISS]). Primary outcome data included hospital mortality/discharge to hospice care and withdrawal of life-sustaining measures. Multivariate logistic regression analyses were used to identify factors independently associated with primary outcome variables. A total of 695 patients were isolated for analysis. Of the total cohort, the rate of hospital mortality or discharge to hospice care was 22% (n= 150) and the rate of withdrawal of life-sustaining measures was 10% (n=66). A multivariate logistic regression model identified GCS <13, pupil nonreactivity, increasing ISS, intraventricular hemorrhage, and neurosurgical intervention as factors independently associated with hospital mortality/hospice. Congestive heart failure (CHF), hypotension, GCS <13, and neurosurgical intervention were independently associated with withdrawal of life-sustaining measures. Poor GCS, pupil nonreactivity, ISS, and intraventricular hemorrhage are independently associated with hospital mortality or discharge to hospice care in patients >80 years with SDH. Pre-existing CHF may further predict withdrawal of life-sustaining measures.

Influence of vertebral manipulations on the autonomic nervous system

Introduction. Although its neurophysiological effects have not been fully elucidated, current evidence suggests the clinical effectiveness of spinal manipulation. Different studies suggest that manual therapy induces changes in the autonomic nervous system (ANS). Recent studies showed that mobilization produced a sympatheticexcitatory effect. However, studies using thrust manipulation appeared to be less consistent in their results.Objectives. The main objective of this review was to evaluate whether spinal manipulation induces effects on the ANS. Another objective was to correlate the changes in the measured variables with the activation or inhibition of the sympathetic or parasympathetic nervous system and with the level of spinal manipulation.Materials and methods. We performed a literature search in the following databases: PubMed, PEDro, CINAHL and OVID, using the keywords «Manipulation, spinal» and «Autonomic Nervous System». The PEDro scale was used to assess the methodological quality.Results. Nine studies met the inclusion criteria. Six trials measured cardiovascular function indicators (blood pressure, heart rate, Heart Rate Variability). Three other trials measured the pupil reaction. In most studies, cervical or upper thoracic region was manipulated.Conclusions. Our review does not provide definitive evidence of the effects of spinal manipulation on the ANS. However, most studies observed the existence of autonomic effects by modifying parameters such as blood pressure or Heart Rate Variability after manipulation. Increased parasympathetic activation probably occurs after cervical and lumbar treatment and increased sympathetic activation after dorsal treatment.

Early Decompressive Craniectomy: A Life Saving Option in Closed Head Trauma

Aim: To determine outcome and factors associated with outcome among patients with closed head injury who underwent decompressive craniectomy. Methodology: Cross sectional analytical study conducted in Neurosurgery Department of teaching hospital Dera Ghazi Khan from January, 2021 to June, 2021. Total 105 patients fulfilling the inclusion criteria were enrolled in the study. Approval of ethical review committee was obtained. All the patients with closed head injury which underwent decompressive craniectomy were included. Socio demographic profile, mode of injury, Glasgow Coma Scale (GCS) at admission time, pupillary reaction and timing from hospital admission to surgery, duration of surgery, length of hospital stay and occurrence of CSF leakage was noted. SPSS version 22 was used for data entry and analysis. Results: Head injury was more common in males. 43.8% cases admitted with GCS score between 3-8 and with head injury by road traffic accident. Leakage of CSF was recorded in 13.3% patients. Mortality was recorded in 18.1% patients. GCS at time of admission, time elapsed between admission and surgery and duration of surgery was significantly associated with the outcome. Conclusion: Early decompressive craniectomy significantly reduce death rate in patients with closed head injury. Keywords: Craniectomy, Outcome, Glasgow coma scale

The “butterfly wings” and midbrain “V” sign of Artery of Percheron infarction

An 80-year-old woman with history of hypertension presented to the emergency department following a fall. Her mental status quickly deteriorated and became obtunded. She was stuporous, and unresponsive to verbal stimuli. She had minimally reactive pupils and was moving extremities to painful stimuli. An MRI scan was performed following an unrevealing CT brain.

Non-Arteritic Anterior Ischemic Optic Neuropathy

Purpose. The case report describes the clinical approach to a patient with optic neuropathy in an optometric practice by simple yet valid methods which can be used auxiliary to standard procedures. Material and Methods. Funduscopy was performed via Volk 90D lens and slitlamp. Functional tests, such as visual acuity, pupil reactions, visual field assessment, colour vision, red saturation test, Pulfrich phenomenon and pupil cycle time test, were employed for their differential diagnosis value. Results. The visual acuity and central colour vision were nor- mal; the other tests revealed abnormal state of the patient‘s right eye or visual pathway. Ophthalmoscopy revealed a disc oedema in one half of the optic nerve head. After urgent referral with tentative diagnosis of optic neuropathy of un- known aetiology, a diagnosis of non-arteritic anterior ischemic optic neuropathy (NA-AION) was made at the eye hospital. Conclusion. In patients with sudden onset of monocular visual disturbances where no obvious lesions in visual axis are found various types of optic neuropathies are a frequent finding. Some of these conditions include systemic diseases, such as multiple sclerosis, and some can be associated to life threatening diseases, such as giant cell arteritis. Keywords optic neuropathy, ischemic optic neuropathy, functional vision testing, visual field, giant cell arteritis

Factors Associated with Ocular Injury in Orbital Fracture Patients: Who Requires Urgent Ophthalmic Evaluation?

Importance: Create validated criteria to identify orbital fracture patients at higher risk for significant ocular injuries. Objective: Determine history and physical examination findings in orbital fracture patients who are associated with ocular injury and warrant urgent assessment by an ophthalmologist. Design, Setting, and Participants: Retrospective chart review of 535 adult orbital fracture patients evaluated at a Level I emergency department between 2014 and 2017, without prior history of orbital fracture, ocular injury, or ocular/orbital surgery. Main Outcomes and Measure: Presence of ocular injury. Results: In total, 195 (36%) patients had an ocular injury. Those with and without ocular injury were compared in a multivariate logistic regression model including demographics, fracture characteristics, injury mechanism, and physical examination findings. Visual acuity change, radiographic retrobulbar hemorrhage, abnormal pupillary reaction, and inability to open the injured eye all had significant associations with ocular injury when other findings were controlled. Conclusion: This study shows a significant association between ocular injury and visual acuity change, retrobulbar hemorrhage, abnormal pupillary reaction, and inability to open the injured eye. These factors can help triage when to obtain an urgent ophthalmology consult.

Anisocoria and Poor Pupil Reactivity by Quantitative Pupillometry in Patients With Intracranial Pathology.

To describe the prevalence and associated risk factors of new onset anisocoria (new pupil size difference of at least 1 mm) and its subtypes: new onset anisocoria accompanied by abnormal and normal pupil reactivities in patients with acute neurologic injuries. We tested the association of patients who experienced new onset anisocoria subtypes with degree of midline shift using linear regression. We further explored differences between quantitative pupil characteristics associated with first-time new onset anisocoria and nonnew onset anisocoria at preceding observations using mixed effects logistic regression, adjusting for possible confounders. All quantitative pupil observations were collected at two neuro-ICUs by nursing staff as standard of care. We conducted a retrospective two-center study of adult patients with intracranial pathology in the ICU with at least a 24-hour stay and three or more quantitative pupil measurements between 2016 and 2018. We studied 221 patients (mean age 58, 41% women). Sixty-three percent experienced new onset anisocoria. New onset anisocoria accompanied by objective evidence of abnormal pupil reactivity occurring at any point during hospitalization was significantly associated with maximum midline shift (β = 2.27 per mm; p = 0.01). The occurrence of new onset anisocoria accompanied by objective evidence of normal pupil reactivity was inversely associated with death (odds ratio, 0.34; 95% CI, 0.16-0.71; p = 0.01) in adjusted analyses. Subclinical continuous pupil size difference distinguished first-time new onset anisocoria from nonnew onset anisocoria in up to four preceding pupil observations (or up to 8 hr prior). Minimum pupil reactivity between eyes also distinguished new onset anisocoria accompanied by objective evidence of abnormal pupil reactivity from new onset anisocoria accompanied by objective evidence of normal pupil reactivity prior to first-time new onset anisocoria occurrence. New onset anisocoria occurs in over 60% of patients with neurologic emergencies. Pupil reactivity may be an important distinguishing characteristic of clinically relevant new onset anisocoria phenotypes. New onset anisocoria accompanied by objective evidence of abnormal pupil reactivity was associated with midline shift, and new onset anisocoria accompanied by objective evidence of normal pupil reactivity had an inverse relationship with death. Distinct quantitative pupil characteristics precede new onset anisocoria occurrence and may allow for earlier prediction of neurologic decline. Further work is needed to determine whether quantitative pupillometry sensitively/specifically predicts clinically relevant anisocoria, enabling possible earlier treatments.

Measuring pupil size and light response through closed eyelids.

Monitoring pupillary size and light-reactivity is a key component of the neurologic assessment in comatose patients after stroke or brain trauma. Currently, pupillary evaluation is performed manually at a frequency often too low to ensure timely alert for irreversible brain damage. We present a novel method for monitoring pupillary size and reactivity through closed eyelids. Our method is based on side illuminating in near-IR through the temple and imaging through the closed eyelid. Successfully tested in a clinical trial, this technology can be implemented as an automated device for continuous pupillary monitoring, which may save staff resources and provide earlier alert to potential brain damage in comatose patients.

English

BACKGROUND Attenuation of vision may be due to underlying organic condition or due to functional visual disorder or malingering if secondary gain is associated. Causes of pathological vision loss include advanced primary open angle glaucoma, hereditary macular dystrophies and optic neuropathies. Problem in establishing diagnosis is faced where superimposition of organic and functional visual loss is there. Distinction between functional visual loss and pathological visual loss is made by thorough and careful examination of the patient by applying basic rules and tools of ophthalmology in which examining surgeon is well versed, but patient is unaware. During routine practice, every ophthalmologist encounters patients with nonorganic vision loss. The purpose of the article is to demonstrate how to distinguish between normal visual function without missing any organic visual loss. Examination of such patients requires number of tests including baseline visual acuity, pupillary reactions, slit lamp examination of anterior segment, fundus examination, visual field analysis, optical coherence tomography, visual evoked potential and electroretinography. By proving integrity and functioning of visual system, diagnosis of functional visual loss can be confirmed. Once the conclusive diagnosis is established, it is to be revealed with caution to the patient/patient’s attendant as it can lead to medico legal issues. Here, we present series of cases who presented to us in a tertiary care center of North India during a period of six months in the year of 2019 where case 1 and case 2 presented with decreased vision due to underlying pathological condition, case 3 presented with reduced vision due to functional visual disorder. Case 4, 5 and 6 provided decisive evidence of malingering. KEY WORDS Fogging, Hysterical Visual Loss, Malingering, Menace Reflex, Optokinetic Nystagmus.

Bilateral optic neuritis with macular edema in a young female: A case report

A 20 year old female, presented with history of swelling of right cheek since 2 weeks associated with fever and rash, blurring of vision in both eyes since 7 days which was sudden in onset and painless. Dilated fundoscopic examination of right eye showed disc edema with hyperemia with macular edema. Left eye showed disc edema with hyperemia, splinter hemorrhage on the disc and macular edema. This case posed a diagnostic challenge as clinically, it did not typically fit into the diagnosis of optic neuritis as the pupil reactions were normal, absence of afferent pupillary defect. However, there was rapid therapeutic response with intravenous injection of Dexamethasone, which improved the visual acuity from <1/60 to 6/6 in about a week. Keyword: Post viral optic neuritis, Macular edema, Anterior ischemic optic neuropathy

New and Off-Label Uses of Tranexamic Acid.

New and Off-Label Uses of Tranexamic Acid.

Larger pupil dilation to nonsocial sounds in infants with subsequent autism diagnosis.

Studies of infants with an elevated likelihood of autism spectrum disorder can identify basic developmental processes that are associated with subsequently emerging clinical symptoms. Atypical responsiveness to sounds in infancy is such a potential early marker of autism. Here, we used pupillometry to quantify reactivity to social and nonsocial sounds in infants with a subsequent diagnosis. Previous research suggest that pupil dilation reflects attentional alerting, and link it to the locus coeruleus norepinephrine system. We measured pupil dilation responses to child-directed speech and the sound of running water; sounds infants often hear in their everyday life. The final sample consisted of 99 ten-month-old infants (52 girls), of whom 68 had an elevated likelihood of autism and 31 were typically developing low-likelihood infants. At follow-up (36 months of age), 18 children in the elevated-likelihood group were diagnosed with autism. Compared to infants without diagnosis, the infants who were subsequently diagnosed with autism had larger pupil dilation when listening to nonsocial sounds, while reactivity to speech was strikingly similar between groups. In the total sample, more pupil dilation to the nonsocial sound was associated with higher levels of autistic symptoms. We also found that on a trial-by-trial basis, across all conditions and groups, more pupil dilation was associated with making fewer gaze shifts. This study did not find evidence of atypical pupillary reactivity to child-directed speech early in life in autism. Instead, the results suggest that certain nonsocial sounds elicit atypically strong alerting responses in infants with a subsequent autism diagnosis. These findings may have important theoretical and clinical implications.

Atypical Pupil Reactions in Brain Dead Patients.

Background: During routine diagnosis of brain death, changes in pupil diameter in response to the stimulation of peripheral nerves are sometimes observed. For example, pupillary dilation after diagnosed brain death is described in the literature as the ciliospinal reflex. However, pupil constriction creates diagnostic doubts. Objective: The pupillometric analysis of pupil response to stimulation of the cervicothoracic spinal cord in patients with diagnosed brain death. Methods: Instrumental tests to confirm the arrest of cerebral circulation were performed in 30 adult subjects (mean age 53.5 years, range 26–75 years) with diagnosed brain death. In addition, a pupillometer was used to measure the change in pupil diameter in response to neck flexion. Intervention: Flexion of the neck and measuring the response in change of the pupil with the use of the pupillometer. Results: The change in the pupil was observed in the examined group of patients. Difference in pupil size ≥ 0.2 mm was observed in 14 cases (46%). In five cases (17%), pupil constriction was found (from 0.2 to 0.7 mm). Measurement error was +/− 0.1 mm. Conclusions: Both pupillary constriction and dilatation may occur due to a ciliospinal reflex in patients with brain death. This phenomenon needs further research in order to establish its pathophysiology.

P-38 UTILITY OF PUPILLARY REACTIVITY IN THE FUNCTIONAL ASSESSMENT OF THE AUTONOMOUS NERVOUS SYSTEM IN PATIENTS WITH CHRONIC LIVER DISEASE: PRELIMINARY RESULTS

Autonomic nervous system (ANS) dysfunction in patients with chronic liver disease (CLD) is associated with greater severity. Heart rate variability (HRV) allows the assessment of ANS, but its implementation is complex. Pupillary reactivity (PR) by automatic pupillometry (AP) also provides this information; however its usefulness in patients with CLD is unknown. To validate the usefulness of PR in the evaluation of ANS in healthy subjects and patients with CLD through association with HRV. Cross-sectional study that includes healthy controls (n = 11) and patients with DHC (n = 26). ANS balance was determined by HRV by Holter rhythm of 5 minutes and RP by AP. HRV / RP of healthy subjects and with CLD, and correlation parameters of both measurements were compared. Significant differences were found between both groups in the parameters of both HRV and RP, demonstrating an imbalance of the ANS in CLD patients. Differences were significant in 2 of 3 time parameters, in 2 of 3 frequency parameters in HRV and in 5 of 7 objectified by AP. The imbalance increases directly according to the Child stage (p <0.001). Patients with CLD have an unbalanced ANS and AP was useful in this study to demonstrate this. The most altered parameters in patients with DHC are directly correlated with the function of the parasympathetic ANS.