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Clinical Examination in Neuro-Ophthalmology
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Selvakumar Ambika, Krishnakumar Padmalakshmi
Clinical assessment should start as soon as the patient enters the examination room, including gait, higher functions and external appearance. Abnormality of eyelid position such as ptosis or lid retraction needs to be noted. History of diurnal variation and fatiguability should be noted for any patient with lid droop to rule out ocular myasthenia. Simple clinical signs like improvement in ptosis after ice test and Cogan's lid twitch are more suggestive of myasthenia. Patients with third nerve palsy and certain myopathies as in chronic progressive external ophthalmoplegia and Miller Fisher syndrome also can present with ptosis, screening old photographs may help us to assess the onset of the findings. Ptosis should not be mistaken for conditions like blepharospasm or apraxia of lid opening. Measurement of palpebral fissure height, levator function and marginal reflex distance has to be done. Evaluation of proptosis is important as it may be associated with life-threatening intracranial and certain intraorbital tumors, carotid-cavernous fistulas, AV malformations, etc. Lid retraction can be a feature of thyroid eye disease or even dorsal midbrain syndrome.
Anatomy of the Forehead and Periocular Region
Published in Neil S. Sadick, Illustrated Manual of Injectable Fillers, 2020
Marcelo B. Antunes, Stephen A. Goldstein
The orbicularis oculi muscle arises medially from the frontal process of the maxilla, lacrimal bone, medial palpebral ligament, and nasal process of the frontal bone. It then extends laterally to insert into the subcutaneous tissue at the lateral part of the orbit (Figure 4.2). The orbicularis oculi is a sphincter of muscle responsible for eye closure. It is divided into three portions: orbital, palpebral, and tarsal. The orbital portion is the thickest, most peripheral portion. The palpebral portion travels from the medial canthal tendon to the lateral canthal tendon immediately underneath the skin of the superior and inferior eyelids. The tarsal portion arises from the posterior lacrimal crest, behind the lacrimal sac, and travels laterally, superficial to the tarsal plate, to insert into the lateral canthal tendon. The palpebral and tarsal portions act involuntarily. They are responsible for the involuntary closure of the eyelids such as during blinking. They also form a significant part of the lacrimal pump system. The orbital portion of the orbicularis is a voluntary muscle. Its contraction results in tight closure of the eyelids, drawing the eyebrows inferiorly and creating rhytides over the lateral portion of the orbit, often called crow’s feet. The action of the orbicularis oculi contributes significantly to facial expression and may be the most important source of nonverbal communication: as we all know, “the eyes are the window to the soul.” Through movement of the eyelids, one can express many emotions, such as pain, anger, fear, and surprise.
Ocular Irritation Testing
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
George P. Daston, F. E. Freeberg
The conjunctiva is a squamous, nonkeratinized epithelium which lines the inner surface of the eyelid (palpebral conjunctiva) and the surface of the nonvisual parts of the eye (bulbar conjunctiva). It contains numerous mucous-secreting goblet cells, especially in the palpebral conjunctiva. The conjunctiva has a rich supply of blood vessels which are visible through the conjunctival epithelium.
Factors associated with the development of blepharoptosis after pars plana vitrectomy surgery
Published in Seminars in Ophthalmology, 2022
Pear Pongsachareonnont, Kornwipa Hemarat, Ronakorn Panjaphongse, Weifeng Liu, M. Reza Vagefi, Jay M. Stewart
Eyelid parameter measurements were performed manually by a single masked observer. In order to obtain the marginal reflex distance (MRD) and levator excursion, the digital photograph was superimposed with Adobe Photoshop CS6© (Adobe Systems Incorporated, San Jose, CA, USA) and measured by ImageJ (Rasband, W.S., ImageJ, National Institutes of Health, Bethesda, Maryland, USA, https://imagej.nih.gov/ij/, 1997–2016.). The palpebral fissure height (PF) was determined as the distance from the upper eyelid margin to the lower eyelid margin, taken at the center of the eyelid. Levator excursion (LE) was obtained by measuring the range of movement of the upper eyelid from down-gaze to up-gaze while neutralizing the eyebrow/frontalis muscle. Marginal reflex distance 1 (MRD1) was defined as the distance between the central corneal light reflex and the upper eyelid margin, with the eyes in primary position. A schematic of eyelid parameter measurement is shown in Figure 1.
Blink detection and magnetic force generation for correction of lagophthalmos, with specific regard to implant compatibility testing
Published in Orbit, 2022
Razek Georges Coussa, Nikita Lomis, Fares Antaki, Jason Samle, Kavita Patel, George Christodoulou, Satya Prakash, James Oestreicher, Bryan Arthurs
Due to the numerous disadvantages and limitations of the above surgical interventions, static and dynamic-based eyelid reanimation therapies, including silicone bands, palpebral springs and gold weights, have become the preferred clinical management of FNP. For instance, a tested and predetermined elastic silicone band was previously placed in the eyelids of lagophthalmos patients in an attempt to close the eyelid through elastic recoil.,10,11 Canthal tendon stretching and dehiscence as well as prosthesis erosion, which require frequent surgical revisions, were the major complications of silicone bands. Palpebral springs to restore dynamic eyelid function were also tested. The lower limb of the spring was implanted in the upper eyelid and the upper limb was implanted in the eyebrow periosteum. The palpebral spring benefited from the sequential interplay between the levator palpebrae (LP) and the orbicularis oculi (OO). During a blink attempt, the LP is inhibited and OO activated allowing for the potential energy stored in the spring to close the eyelid. The use of palpebral springs required transcutaneous adjustments in 50% of cases and often resulted in spring extrusion, migration and even infection.7,12
Neuroprotective Effect of Intravitreal Single-Dose Lithium Chloride after Optic Nerve Injury in Rats
Published in Current Eye Research, 2021
Moein Ala, Razieh Mohammad Jafari, Hossein Nematian, Mohammad Reza Ganjedanesh, Asieh Naderi, Mostafa Akbariani, Mehdi Sanatkar, Leila Satarian, Masoud Aghsaei Fard, Ahmad Reza Dehpour
After deep anesthesia, the forehead hairs were shaved and the animals were prepared for surgery. Right eye of each rat underwent trauma and the left eye was treated with lithium chloride after trauma induction. In another group of rats, trauma was induced in the right eyes and changes were compared with undamaged fellow eyes which were not injected with the solvent. In order to expose optic nerve, superior palpebral was incised from midline and a small space was opened above the eyeball just located right under the ridge of frontal bone. After optic nerve exposure, clamp was inserted around it exactly behind the eyeball, then after 20-second, clamp was taken and palpebral was sutured. In the treated group, lithium was injected into vitreous space immediately after clamping optic nerve by Hamilton microsyringe. The volume of solution for each injection was 2 µL. The right eye was not injected. At the end tetracycline ointment was rubbed on the surgery site to prevent infection. In order to harvest retinal tissue, after deep anesthesia rats were euthanized by using CO2 camber and eyeball’s attachments to periorbital tissue were slightly removed. Then, forceps were used to incise optic nerve and extract eyeball. The eyeball was inserted in sterile normal saline, then anterior and posterior eye chamber were separated from the corneoscleral junction. A slight cut was exerted to help determine retinal and scleral deattachment. Finally, the retina was separated with a mild tension. The experimental design of this study is shown in Figure 1.