Oculomotor Function In Patients Research Articles

Abnormalities of the oculomotor function in type 1 diabetes and diabetic neuropathy

AimsAbnormalities in the oculomotor system may represent an early sign of diabetic neuropathy and are currently poorly studied. We designed an eye-tracking-based test to evaluate oculomotor function in patients with type 1 diabetes.MethodsWe used the SRLab—Tobii TX300 Eye tracker®, an eye-tracking device, coupled with software that we developed to test abnormalities in the oculomotor system. The software consists of a series of eye-tracking tasks divided into 4 classes of parameters (Resistance, Wideness, Pursuit and Velocity) to evaluate both smooth and saccadic movement in different directions. We analyzed the oculomotor system in 34 healthy volunteers and in 34 patients with long-standing type 1 diabetes.ResultsAmong the 474 parameters analyzed with the eye-tracking-based system, 11% were significantly altered in patients with type 1 diabetes (p < 0.05), with a higher proportion of abnormalities observed in the Wideness (24%) and Resistance (10%) parameters. Patients with type 1 diabetes without diabetic neuropathy showed more frequently anomalous measurements in the Resistance class (p = 0.02). The classes of Velocity and Pursuit were less frequently altered in patients with type 1 diabetes as compared to healthy subjects, with anomalous measurements mainly observed in patients with diabetic neuropathy.ConclusionsAbnormalities in oculomotor system function can be detected in patients with type 1 diabetes using a novel eye-tracking-based test. A larger cohort study may further determine thresholds of normality and validate whether eye-tracking can be used to non-invasively characterize early signs of diabetic neuropathy.Trial: NCT04608890.

Vestibular and oculomotor function in patients with vestibular migraine

AimThe purpose of this study was to assess the vestibular and oculomotor function in patients with vestibular migraine (VM). And we also investigate the relationship between testing results and effectiveness of preventive medications in VM. Material and method41 patients with VM were recruited in this study and examined with cervical and ocular vestibular evoked myogenic potential(cVEMP, oVEMP), video head impulse test(vHIT), caloric test and videonystagmography. All patients were treated with preventive medications. We calculated symptomatic improvement and record episodes frequency in patients with VM. Six months later, the effectiveness of preventive medications were evaluated and the relationship between vestibular testing and effectiveness of preventive medications were analyzed further. ResultsIn vestibular function testing, 73% of patients with VM showed abnormal results. Abnormal cVEMP, oVEMP, vHIT, and caloric test were found in 20%, 44%, 32% and 56% respectively. The abnormal rate of oVEMP was significantly higher than that of cVEMP(p < 0.05). And the proportion of abnormal caloric test was obviously higher than that of vHIT (p < 0.05). In oculomotor function testing, 42% of the patients with VM showed pathological results which was significantly lower than that of vestibular function testing(p < 0.05). After 6 months follow-up, the proportion of prophylactic medication effectiveness was significantly higher in normal vestibular function testing group compared with the abnormal group (p < 0.05). ConclusionAbnormal vestibular and oculomotor functions are commonly observed in patients with VM. And these patients with abnormal vestibular function possess a weak effectiveness of preventive medications.

Nocturnal eye movements in patients with idiopathic rapid eye movement sleep behaviour disorder and patients with Parkinson's disease.

Patients with idiopathic rapid-eye-movement (REM) sleep behaviour disorder (iRBD) have a high risk of converting into manifest α-synucleinopathies. Eye movements (EMs) are controlled by neurons in the lower brainstem, midbrain and frontal areas, and may be affected by the early neurodegenerative process seen in iRBD. Studies have reported impairment of the oculomotor function in patients with Parkinson's disease (PD) during wakefulness, but no studies have investigated EMs during sleep. We aimed to evaluate nocturnal EMs in iRBD and PD, hypothesizing that these patients present abnormal EM distribution during sleep. Twenty-eight patients with periodic limb movement disorder (PLMD), 24 iRBD, 23 PD without RBD (PDwoRBD), 29 PD and RBD (PDwRBD) and 24 controls were included. A validated EM detector automatically identified EM periods between lights off and on. The EM coverage was computed as the percentage of time containing EMs during stable wake after lights off, N1, N2, N3 and REM sleep. Between-group comparisons revealed that PDwRBD had significantly less EM coverage during wake and significantly higher EM coverage during N2 compared to controls and PLMD patients. PDwoRBD showed significantly less EM coverage during wake compared to controls and higher EM coverage during N2 compared to controls and PLMD. Finally, iRBD showed less coverage of EM during wake compared to controls. The same trend was observed between iRBD and controls in N2 but was not significant. The different profiles of EM coverage in iRBD and PD with/without RBD may mirror different stages of central nervous system involvement across neurodegenerative disease progression.

Oculomotor functions in focal dystonias: A systematic review.

Focal Dystonia (FD) is a chronic neurological disorder, which causes twisting and repetitive movements and abnormal postures induced by involuntary sustained contractions of agonist and antagonist muscles.Based on the hypothesis that several dystonia-related brain regions, including cerebellum, are implicated in oculomotor disturbances (OCD), a number of studies investigated oculomotor function in patients with dystonia. However, conceptual clarity with respect to the used assessment tools and interpretation of the findings is lacking in the literature. This is the first article to systematically review studies that assessed oculomotor function in patients with FD.In total, 329 publications, published until September 1, 2019, were identified through MEDLINE search. Twenty out of 329 studies, involving 232 subjects in total, met the inclusion criteria. Most of the studies reported oculomotor disturbances in patients with FD. Abnormalities included asymmetry in vestibulo-ocular reflex (VOR), disturbances in saccadic functions, and prolonged latencies of eye motion. Discrepancies in the results could be explained, at least partially, by the long period of time over which the reviewed studies were published, the different methods used for testing the eye movements, and the limited number of patients assessed since the majority of data derived from case reports or small-scale studies. Further prospective studies with larger subject numbers are needed, using advanced tools for the assessment of oculomotor function in focal dystonia.

El abecedario de los movimientos oculares

Introduction and objective: In recent years, significant progress has been made in the diagnosis of vestibular pathologies, especially in the use of alterations in eye movements for diagnosis. An orderly way of evaluating ocular motor function in patients with vestibular system involvement is presented in this review. Method: Narrative review. Results: 7 articles were selected. Discussion: The use of ABCs mnemonics is proposed to order the examination of oculomotor function in patients with vestibular system involvement. The ABC segment involves the evaluation of the Conjugated Ocular Bilateral Alignment; D is the examination of the Dynamics of eye movements; E refers to the stability of the oculomotor system; FGHI refers to Eye Fixation, Gain in movements and Head Impulse (cephalic impulse). Conclusions: Using this approach, omissions are avoided in the semiological examination and it can share the information in a homogeneous way among health professionals.

Assessment of Oculomotor Function in Patients With Postconcussion Syndrome: A Systematic Review.

Concussion and its associated sequel, postconcussion syndrome (PCS), have a debilitating impact on the lives of concussed patients. However, a diagnostic biomarker for this condition is lacking. Recently, there has been a surge of interest in using oculomotor function testing as an objective assessment of patients with PCS. To systematically synthesize, appraise, and summarize all published empirical studies that have assessed alteration of oculomotor functions in patients with PCS. Medline, Embase, PsychINFO, and CINAHL databases searched up to July 2016 for studies that used oculomotor function assessment in patients with postconcussion symptoms. The search identified 1637 citations, and finally 8 case-control studies were included. Of these, 5 studies used a similar task with a target moving in a circular trajectory. Three other studies measured conventional oculomotor tasks such as saccade, vergence, and smooth pursuit eye movements. Currently, there is limited support for the recommendation of oculomotor function assessments for diagnosis and identification of patients with PCS following head trauma. Therefore, more rigorous studies assessing oculomotor function changes in patients with PCS are warranted.

Effect of Subthalamic Nucleus or Globus Pallidus Interna Stimulation on Oculomotor Function in Patients with Parkinson’s Disease

Background: Deep brain stimulation (DBS) of either the globus pallidus interna (GPi) or subthalamic nucleus (STN) is similarly effective for treating somatomotor manifestations of Parkinson’s disease (PD), but differences in how stimulation of each target affects oculomotor function are poorly understood. Objective: We sought to determine if stimulation of the STN, but not the GPi, affects oculomotor function in PD patients. Methods: Nineteen PD patients with DBS implants (8 bilateral GPi, 9 bilateral STN and 2 unilateral STN) were studied. Testing was performed with stimulation on, then off. Somatomotor function was tested using the Unified Parkinson’s Disease Rating Scale (UPDRS) motor exam. For oculomotor testing, patients performed pro- and antisaccade tasks while monitored with an infrared eye tracker. Saccadic latency, saccadic intrusions, and square-wave jerks (SWJs) were measured for each trial. Results: As expected, UPDRS motor scores improved with both GPi and STN stimulation. With GPi stimulation, there was no significant difference in oculomotor function with stimulation on or off. However, with STN stimulation on, there was a significant increase in the mean number of SWJs/s, as well as a significant decrease in latency for both pro- and antisaccade tasks. Conclusion: Stimulation of either GPi or STN had similar effects on somatomotor function, but only STN stimulation significantly altered oculomotor function.

An fMRI Study of Saccadic and Smooth-Pursuit Eye Movement Control in Patients with Age-Related Macular Degeneration

To compare the cortical networks that underlie oculomotor function in patients with age-related macular degeneration (AMD) with those in normally sighted control subjects, using functional magnetic resonance imaging (fMRI). Six patients with bilateral geographic retinal atrophy due to AMD (age range, 55-83 years) were recruited for the study. The visual acuities of the patients ranged from 20/76 (0.58 logMAR) to 20/360 (1.26 logMAR). An additional six younger (age range, 22-31 years) and six older (age range, 54-78 years) normally sighted individuals were recruited as control subjects. fMRI data were acquired on a 3.0-Tesla, scanner while subjects performed visually guided saccade (VGS) and smooth-pursuit (SmP) tasks. Contrasts between VGS and fixation on a stationary target identified a network of activation that included the frontal eye fields (FEFs), supplementary eye fields (SMA/SEFs), prefrontal cortex (PFC), intraparietal sulci (IPS), and the areas of the visual cortex (MT/V5, V2/V3, and V1) in control subjects and patients. A similar network was identified for comparisons between SmP and periods of fixation. Marked variability was observed in the performance of both tasks across all patients. For both tasks, the patients generally showed increased PFC and IPS activation, with decreased activation in visual cortex compared with the control subjects. The patients showed significantly increased activation of the FEFs and SMA/SEFs in the SmP task, compared with the control subjects. These data suggest that performance of both eye movement tasks required greater involvement of the cortical regions generally implicated in attention and effort in patients with AMD.

Neurological, Cardiological, and Oculomotor Progression in 104 Patients With Friedreich Ataxia During Long-term Follow-up

Friedreich ataxia (FA) is the most frequent autosomal recessive cerebellar ataxia. Although the phenotype is well known, disease progression has not been evaluated in a prospective manner. To perform a long-term prospective follow-up of neurological, cardiological, and oculomotor function in patients with FA (FA patients). In this open-labeled prospective survey, we examined 104 FA patients every 6 months during a median period of 5 years (range, 6 months to 7 years), with a systematic standardized protocol. Data are reported as mean +/- SD. Neurological examinations were performed at the Federation of Neurology and the Department of Genetics of the Salpêtrière Hospital, Paris, France. Cardiological follow-up was performed at the Department of Cardiology; oculomotor examinations were performed at the Institut National de la Santé et de la Récherche Médicale Unit 679, at the same hospital. Patients We studied 104 FA patients with a confirmed molecular diagnosis. None were receiving antioxidant therapy at baseline; 88 accepted treatment with the coenzyme Q(10) analogue idebenone (5 mg/kg per day). Sixteen preferred not to be treated. Neurological status was evaluated with the International Cooperative Ataxia Rating Scale (ICARS) and a quantitative writing test. Cardiological evaluations included echocardiography, electrocardiography, and Holter monitoring. Oculomotor function was evaluated by electro-oculography to determine the frequency of square wave jerks. The total ICARS score worsened during follow-up, whether or not the patients were treated with idebenone (1.93 +/- 0.25 and 4.43 +/- 1.56 points per year, respectively). The total ICARS score increased faster in patients with onset before age 15 years compared with the others (2.6 +/- 0.4 [n = 51] vs 1.1 +/- 0.3 [n = 37]; P = .05). The posture subscore increased faster in patients able to stand at baseline, who also had shorter disease durations than patients unable to stand (1.25 +/- 0.12 vs 0.47 +/- 0.22 point per year; P<.001). Neurological progression was underestimated, however, by the ICARS scores, which reached a plateau in patients with long disease durations. Oculomotor function slightly deteriorated (0.09 +/- 0.02 Hz per year; P<.001). Left ventricular mass index decreased (-4.1 +/- 1.5 g/m(2) per year; P = .008), as did ejection fraction (-1.32% +/- 0.29% per year; P<.001). The neurological condition of FA patients deteriorated slowly over time, even with idebenone treatment. Although cardiac hypertrophy decreased under treatment, cardiac function did not improve. The ICARS scale is not appropriate to evaluate the progression of FA in patients with long disease durations. Additional quantitative measures may improve the reliability of this scale.

Cervicocephalic kinesthetic sensibility, active range of cervical motion, and oculomotor function in patients with whiplash injury

Objective: To investigate cervicocephalic kinesthetic sensibility, active range of cervical motion, and oculomotor function in patients with whiplash injury. Design: A 2-year review of consecutive patients admitted to the emergency unit after whiplash injury. Setting: An otorhinolaryngology department. Patients and Subjects: Twenty-seven consecutive patients with diagnosed whiplash injury (14 men and 13 women, mean age, 33.8yrs [range, 18 to 66yrs]). The controls were healthy subjects without a history of whiplash injury. Main Outcome Measures: Oculomotor function was tested at 2 months and at 2 years after whiplash injury. The ability to appreciate both movement and head position was studied. Active range of cervical motion was measured. Subjective intensity of neck pain and major medical symptoms were recorded. Results: Active head repositioning was significantly less precise in the whiplash subjects than in the control group. Failures in oculomotor functions were observed in 62% of subjects. Significant correlations occurred between smooth pursuit tests and active cervical range of motion. Correlations also were established between the oculomotor test and the kinesthetic sensibility test. Conclusion: The results suggest that restricted cervical movements and changes in the quality of proprioceptive information from the cervical spine region affect voluntary eye movements. A flexion/extension injury to the neck may result in dysfunction of the proprioceptive system. Oculomotor dysfunction after neck trauma might be related to cervical afferent input disturbances.

Amyotrophic lateral sclerosis: oculomotor function in patients in respirators.

Amyotrophic lateral sclerosis: oculomotor function in patients in respirators.

Oculomotor function in patients with Parkinson's disease

Seventy patients with Parkinson's disease were examined specifically for several oculomotor functions. Representative patients had eye movements recorded electro-oculographically. This demonstrated some defects not clinically apparent and accentuated others. A surprisingly high percentage (75%) of patients showed some degree of impairment of some form of oculomotor function. There was a wide range of degree of disability, i.e., jerkiness, “cog-wheeling” or “saccadic motion”, mild limitation of extent of gaze or dissociation of sequence of motion such as head turning preceding horizontal ocular deviation and limitation or even absence of gaze in various planes. Of the latter the most prominent was impairment of upward gaze which was somewhat more frequently encountered than was abnormality of downward gaze. Lateral gaze and convergence defects were less common. Eyelid abnormalities in the form of blepharospasm, lid retraction and ptosis were frequently encountered. Pupillary abnormalities were uncommon. Oculomotor dysfunction tended to be more severe in cases where other concomitant features of Parkinsonism were very prominent. A short-term study of the effects of levodopa therapy was conducted in 29 patients. There was a very poor response of oculomotor dysfunction, despite improvement in other Parkinsonian features in many of the patients.