Normal and abnormal lid function

Lesion network mapping of eye-opening apraxia

Apraxia of eyelid opening (or eye-opening apraxia) is characterized by the inability to voluntarily open the eyes because of impaired supranuclear control. Here, we examined the neural substrates implicated in eye-opening apraxia through lesion network mapping. We analysed brain lesions from 27 eye-opening apraxia stroke patients and compared them with lesions from 20 aphasia and 45 hemiballismus patients serving as controls. Lesions were mapped onto a standard brain atlas using resting-state functional MRI data derived from 966 healthy adults in the Harvard Dataverse. Our analyses revealed that most eye-opening apraxia-associated lesions occurred in the right hemisphere, with subcortical or mixed cortical/subcortical involvement. Despite their anatomical heterogeneity, these lesions functionally converged on the bilateral dorsal anterior and posterior insula. The functional connectivity map for eye-opening apraxia was distinct from those for aphasia and hemiballismus. Hemiballismus lesions predominantly mapped onto the putamen, particularly the posterolateral region, while aphasia lesions were localized to language-processing regions, primarily within the frontal operculum. In summary, in patients with eye-opening apraxia, disruptions in the dorsal anterior and posterior insula may compromise their capacity to initiate the appropriate eyelid-opening response to relevant interoceptive and exteroceptive stimuli, implicating a complex interplay between salience detection and motor execution.

The effectiveness and safety of eyelid defect reconstruction after sebaceous carcinoma of the eyelid surgery: A protocol for systematic review and meta-analysis

INTRODUCTION

Sebaceous carcinoma of the eyelid is the third most common eyelid malignancy, after basal cell carcinoma and squamous cell carcinoma. It is highly malignant and potentially aggressive. Surgical excision is currently the best treatment option for this condition. Patients often require reconstruction surgery to repair eyelid defects to achieve normal eyelid function and appearance. However, no comprehensive systematic review has assessed the efficacy and safety of eyelid defect reconstruction. This protocol was developed to conduct a systematic review and meta-analysis to evaluate evidence related to the efficacy and safety of reconstruction.

METHODS

We will systematically search the Cochrane Library, PubMed, Web of Science, China National Knowledge Infrastructure, WanFang Database, and Chinese Biomedical Literature Database from their inception to February 2023 for studies on eyelid defect reconstruction. We will identify other potential studies using multiple methods such as manual searching. The outcomes were eyelid function, eyelid morphology, patient satisfaction, recurrence rate, metastasis rate, tumor-related mortality, and adverse events. Two researchers will independently screen titles and abstracts, identify full-text studies for inclusion, extract data, and appraise the risk of bias in the included studies. A meta-analysis will be conducted using Review Manager 5.4 and R software. The certainty of evidence will be appraised by grading of recommendations, assessment, development, and evaluation system.

RESULTS

This full-text will adhere to the preferred reporting items for systematic reviews and meta-analyses statement to ensure clarity and completeness of reporting in all phases of the systematic review.

DISCUSSION

This study provides evidence of the efficacy and safety of reconstruction methods for sebaceous carcinoma of the eyelid.

Biomechanics of open-globe injury: a review

Open-globe injury is a common cause of blindness clinically caused by blunt trauma, sharp injury, or shock waves, characterised by rupture of the cornea or sclera and exposure of eye contents to the environment. It causes catastrophic damage to the globe, resulting in severe visual impairment and psychological trauma to the patient. Depending on the structure of the globe, the biomechanics causing ocular rupture can vary, and trauma to different parts of the globe can cause varying degrees of eye injury. The weak parts or parts of the eyeball in contact with foreign bodies rupture when biomechanics, such as external force, unit area impact energy, corneoscleral stress, and intraocular pressure exceed a certain value. Studying the biomechanics of open-globe injury and its influencing factors can provide a reference for eye-contact operations and the design of eye-protection devices. This review summarises the biomechanics of open-globe injury and the relevant factors.

Eye Blink-Associated Saccades

Saccades function to bring targets of interest into the field of view. They are one of the four types of basic eye movements in humans, all of which are generated and modulated by components of a complex eye movement network, involving cortical eye fields, thalami, basal ganglia, cerebellum, and brainstem structures. Similarly, blinks are presumed to be generated by a blink center involving complex cortical and subcortical pathways. An association between saccades and blinks is well established; when these circuits are disrupted, normal saccadic parameters change. We report a case of a 48-year-old female who presented with fatigue and weakness. She had a complicated medical history, including drug-resistant epilepsy with subsequent vagus nerve stimulator (VNS) placement, right anterior temporal lobectomy, and craniotomy for a residual right temporal lobectomy and amygdalohippocampectomy. The latter was complicated by ischemic right middle cerebral artery (MCA) territory stroke with residual left hemiplegia. Her examination was unremarkable with regards to the presenting complaints, but one unique finding was observed; she demonstrated abnormal conjugate eye movements to the left associated with each blink. These eye movements continued to be present even after the patient's ability to fixate on an object was removed. It was unclear how long this finding had been present. A review of her MRI of the brain from 10 months prior showed encephalomalacia and surrounding gliosis in the right MCA territory, right temporal laminar necrosis, right basal ganglia and parietal lobe microhemorrhages, ex vacuo dilatation of the right lateral ventricle, and a rightward midline shift. Saccadic abnormalities have been reported in a variety of conditions. The eye blink-associated saccades seen here are rare. To our knowledge, only one other patient has been reported with similar blink-associated eye movements after brain injury following a right MCA territory stroke. The exact mechanism underlying these eye movements is unclear, but may involve aberrant or disrupted neuronal signaling in cortical and/or basal ganglia components of the eye movement network, or related to an as yet unknown blink-saccadic regulatory mechanism.

Impact of Upper Eyelid Surgery on Symptom Severity and Frequency in Benign Essential Blepharospasm

Objective

To assess the impact of periocular surgery, other than orbicularis stripping, on the severity and frequency of blepharospasm symptoms.

Methods

Consecutive patients with benign essential blepharospasm (BEB) who underwent eyelid/eyebrow surgery with the aim of improving symptoms were retrospectively reviewed over a 5-year period. Patients who had completed the Jankovic Rating Scale (JRS) and Blepharospasm Disability Index (BDI) pre- and at least 3 months postoperatively were included.

Results

Twenty-four patients were included. JRS scores significantly improved from 7.0 preoperatively to 4.1 postoperatively (p < 0.001), and BDI scores significantly improved from 18.4 preoperatively to 12.7 postoperatively (p < 0.001); the mean percentage improvements were 41% and 30%, respectively. Patients were followed for a median of 24 months postoperatively.

Conclusion

Periocular surgery significantly reduced BEB symptoms in the majority (83%) of patients by an average of 33% and may therefore be offered for suitable patients. An important minority (17%) of patients experienced symptom worsening.

After stroke, apraxia of eyelid opening is associated with high mortality and right hemispheric infarction

INTRODUCTION

Apraxia of eyelid opening (AEO) refers to impaired voluntary eyelid elevation of supranuclear origin. AEO is well-described in neurodegenerative disorders, but its frequency in stroke is unknown.

METHODS

To investigate the frequency of AEO after stroke, we enrolled patients with an anterior circulation occlusion admitted for endovascular thrombectomy (EVT). Exclusion criteria were posterior circulation stroke, impaired consciousness and ophthalmological disorders. Forty-eight hours after EVT, patients were screened for AEO, conjugated gaze palsies and cortical ptosis. Neurological deficits were classified using the National Institute of Health Stroke Scale (NIHSS). A blinded neuroradiologist analyzed CT brain 24 h after EVT using the Alberta Stroke Program Early CT Score.

RESULTS

Ninety-eight EVT patients were included in 9 months. Six patients had AEO (6%), 37 conjugated gaze palsy (38%) and 16% cortical ptosis (16%). AEO was associated with higher median NIHSS compared to no eye symptoms (18.5 vs. 3; p < 0.001) and gaze palsy or cortical ptosis (18.5 vs. 7; p = 0.003). The median modified Rankin Scale (mRS) after 3 months was 2 in patients without AEO, but 6 in patients with AEO (mRS in AEO patients nr. 1-6: 3, 4, 6, 6, 6, and 6; p = 0.015; no longer significant after adjustment for stroke severity), including 4 deaths (66%) in AEO patients. All patients with AEO had right hemisphere stroke (6/6 vs. 43/98 in total, p = 0.006).

CONCLUSION

AEO was observed in 6% of EVT patients who showed poor survival and outcome. AEO occurred exclusively in right hemispheric infarctions, suggesting that supranuclear eyelid control is under the influence of the right cerebral hemisphere.

Early cicatricial lagophthalmos release with pentagonal wedge resection of the scar, fat redistribution, and full-thickness skin grafting

The specialized structure of the upper eyelid ensures complete closure of the eye and eyeball sealing. An upper eyelid injury can cause various symptoms associated with eyeball trauma, not just scar formation or eyelid deformity. In this report, we describe a case of lagophthalmos observed after wound repair in a patient with a crushing injury caused by a grinder. Several surgical techniques are used to treat lagophthalmos or scar contracture. In most cases, a releasing procedure is performed after 6 months of initial repair. However, if the patient has severe symptoms that are not relieved by conservative care, early revision is inevitable. We describe a case of early lagophthalmos successfully resolved with pentagonal wedge resection, fat redistribution, and full-thickness skin grafting. After the revisional surgery, we observed that the patient regained the ability to completely close the injured eyelid, with restoration of function and favorable cosmetic outcomes. Pentagonal wedge resection to release a retracted structure, fat redistribution to prevent readhesion, and full-thickness skin grafting for enough amount of skin to regain upper eyelid function is useful for scar release and lagophthalmos following crushing injuries of the upper eyelid.

The Three Nociceptive Responses of the Orbicularis Oculi Reflex in Alzheimer's Disease: State of the Evidence and Meta-analysis

There is an emerging belief that electrically elicited blink reflexes (BR) may distinguish Alzheimer's disease (AD) from other disorders characterized by memory dysfunction. To qualitatively and quantitatively distinguish the effects that electrical stimulation has over the blink reflex (eBR) recorded from patients with AD and healthy controls (HCs), we did a systematic review of the literature, and conducted a meta-analysis. Following our selected criteria, 94 AD patients and 97 HCs were identified from articles published in English between 1950 and 2017. Although the 3 responses (R1, R2 and R3) of the eBR were studied in a number of patients, only the R2 response was quantified in all studies. Thresholds and stimulation intensities parameters were found to be used in a miscellaneous form, and the majority of times, such parameters deviated from validated guidelines. The stimulation frequencies used to elicit the BR responses ranged between 0.14 and 0.2 Hz. These frequencies favored HCs compared with AD patients (odds ratio = 1.08; 95% CI = 0.30-1.85), I² = 0% [P = .99]; Q = 271.89 [df = 7, P < .000]). Egger's regression test suggested publication bias (intercept = 32.38; 95% CI = -8.98 to -3.2; P = .001). Our results unveiled key shortcomings in the data reported; such shortcomings need to be corrected in future AD research looking for obtaining more reliable and reproducible eBR studies; otherwise, interventions may be misleading.

High-precision piezo-ejection ocular microdosing: Phase II study on local and systemic effects of topical phenylephrine

AIM

Conventional eyedropper-delivered volumes (25-50 µl) exceed the eye's usual tear-film volume (7 µl) and precorneal reservoir capacity, risking overflow and ocular/systemic complications. Piezoelectric high-precision microdosing may circumvent these limitations. Results & methodology: In this masked, nonrandomized, cross-over study, subjects (n = 12) underwent pupil dilation with topical phenylephrine (PE) administered by 32-µl eyedropper (2.5% or 10% formulation) and 8-µl electronic microdosing (10% formulation). Microdosing with PE-10% achieved comparable peak dilation as 10% eyedropper-delivery and superior dilation to 2.5% eyedropper-delivery (p = 0.009) at 75 min. Microdosing significantly reduced 20-min plasma PE levels versus PE10% eyedropper; neither treatment altered heart rate/blood pressure. Eye irritation occurred significantly less frequently with microdosing than PE10% eyedrops.

CONCLUSION

Piezo-ejection PE microdosing achieves comparable biological effect as eyedropper dosing; reduced systemic absorption may decrease risk of systemic side effects.

Eyelid Dysfunction in Neurodegenerative, Neurogenetic, and Neurometabolic Disease

Eye movement abnormalities are among the earliest clinical manifestations of inherited and acquired neurodegenerative diseases and play an integral role in their diagnosis. Eyelid movement is neuroanatomically linked to eye movement, and thus eyelid dysfunction can also be a distinguishing feature of neurodegenerative disease and complements eye movement abnormalities in helping us to understand their pathophysiology. In this review, we summarize the various eyelid abnormalities that can occur in neurodegenerative, neurogenetic, and neurometabolic diseases. We discuss eyelid disorders, such as ptosis, eyelid retraction, abnormal spontaneous and reflexive blinking, blepharospasm, and eyelid apraxia in the context of the neuroanatomic pathways that are affected. We also review the literature regarding the prevalence of eyelid abnormalities in different neurologic diseases as well as treatment strategies (Table 1).

Blink-associated contralateral eccentric saccades as a rare sign of unilateral brain injury

OBJECTIVE

To describe a rare sign of unilateral brain injury as a form of unwanted blink-associated contralateral eccentric saccades.

METHODS

A 62-year-old patient who underwent an ischemic stroke affecting the entire right middle cerebral artery territory came to our attention 1 year after stroke, manifesting with transient contralateral conjugate gaze deviations associated with spontaneous blinking. We complemented the regular neurologic evaluation with brain MRI, study of evoked potentials, electroneurography of the facial nerve, and infrared video-oculoscopy.

RESULTS

The patient had left-sided hemiparesis, hypoesthesia, hemianopia, and hemispatial neglect. He also showed the occurrence of a rapid leftward conjugate deviation of the eyes, followed by a corrective movement to the primary ocular position. MRI showed a wide malacic area spanning the right frontal, temporal, and parietal cortical and subcortical regions, with signs of wallerian degeneration of the descending right corticospinal tract. Motor and somatosensory evoked potentials were centrally altered on the right side. Electroneurography of the facial nerves was normal. Infrared video-oculoscopy indicated persistence of the same blink-related saccades even in darkness.

CONCLUSIONS

It is known that unilateral cerebral lesions may manifest with a contralateral conjugate gaze deviation evoked by closure of the lids. This sign, known as spasticity of conjugate gaze, may be due to the suppression of the fixation reflex. In our case, the persistence of this sign in the darkness allowed us to exclude this diagnosis. We hypothesized that the blink-related neural pathways may improperly activate the oculomotor circuitry at both the cortical and subcortical levels.

Topiramate-Induced Persistent Eyelid Myokymia

Background. Topiramate (TPM) is a psychotropic drug, which is used mainly as an antiepileptic drug and now over the years is used for a wider range of indications, including migraine prophylaxis and binge eating disorders. Although ocular side effects of Topiramate have been frequently reported, neuroophthalmologic manifestations such as myokymia are rarely reported. Case Presentation. This case report presents a case of a 47-year-old woman who had begun TPM for binge eating problem. She developed unilateral long standing lower eyelid twitching, which progressed to upper eyelid and eyebrow at the same side. The patient was not a smoker or excessive alcohol or caffeine abuser. Increasing the resting time and changing life style made no significant changes in her eyelid twitching. There was no definite evidence by neuroimaging and clinical or laboratory evaluations causing eyelid myokymia. The symptoms resolved with discontinuation of TPM. Conclusion. Although eyelid myokymia is a benign and self-limited condition, it sometimes becomes a source of distress in chronic long standing cases. Physicians should be aware of the neuroophthalmologic side effects of this drug.

The TFOS International Workshop on Contact Lens Discomfort: report of the subcommittee on neurobiology

This report characterizes the neurobiology of the ocular surface and highlights relevant mechanisms that may underpin contact lens-related discomfort. While there is limited evidence for the mechanisms involved in contact lens-related discomfort, neurobiological mechanisms in dry eye disease, the inflammatory pathway, the effect of hyperosmolarity on ocular surface nociceptors, and subsequent sensory processing of ocular pain and discomfort have been at least partly elucidated and are presented herein to provide insight in this new arena. The stimulus to the ocular surface from a contact lens is likely to be complex and multifactorial, including components of osmolarity, solution effects, desiccation, thermal effects, inflammation, friction, and mechanical stimulation. Sensory input will arise from stimulation of the lid margin, palpebral and bulbar conjunctiva, and the cornea.