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Comparison of the Scleral Search Coil and Video-Oculography Techniques for Three-Dimensional Eye Movement Measurement
Published in Michael Fetter, Thomas Haslwanter, Hubert Misslisch, Douglas Tweed, Three-Dimensional Kinematics of Eye, Head and Limb Movements, 2020
W. Teiwes, D.M. Merfeld, L.R. Young, A.H. Clarke
A further effect, which is illustrated in Figure 3, is the shift in baseline that occurs at about 12s, concomitant with the first blink. The SSC is suddenly moved up by about 3° relative to the VOG, but then restores to correspondence over the next 1–2 seconds. This shift occurs during, or as a result of, a vertical saccade associated with an eye blink. There are two likely sources for this shift. It is possible that the VOG camera shifted with respect to the head. In the present example, this would have been an abrupt slippage. However, past experience indicates that camera slippage tends to be gradual, and can usually be recognised by visual inspection of the video recording. Post-analysis viewing of this specific data sequence did not reveal any evidence of slippage,The SSC annulus could have slipped on the eyeball. This can occur when the eyelid mechanically levers the leads of the coil, or the annulus is moved on the eyeball due to the large rotation on eye closure (Bell’s phenomenon).
Head and neck
Published in Tor Wo Chiu, Stone’s Plastic Surgery Facts, 2018
Bell’s phenomenon: eyeballs rotate upwards when the lids are closed. Some patients do not have this, and one should be much less aggressive with ptosis correction in these patients as over-correcting may lead to corneal exposure during sleep.
Acute facial palsy
Published in S. Musheer Hussain, Paul White, Kim W Ah-See, Patrick Spielmann, Mary-Louise Montague, ENT Head & Neck Emergencies, 2018
Richard M Irving, Raghu Nandhan Sampath Kumar
Bell’s palsy normally presents with sudden onset of unilateral lower motor nerve facial palsy over a course of 24–48 hours. It is frequently preceded by periauricular paresthesia or otalgia. A viral prodome may exist, and dysgeusia, hyeracusis and facial numbness may be present. Tearing may be reduced, but paradoxically the patient may complain of excess tears due to loss of lower lid control. Examination includes assessment of facial nerve function, remaining cranial nerves, otoscopy and palpation of the parotid. Specifically, the degree of eye closure and presence of Bell’s phenomenon should be determined, to quantify corneal risk. A baseline pure tone audiogram should be obtained, especially if the patient complains of hearing loss, as this is not typical in Bell’s palsy. Ocular care takes precedence in cases where there is incomplete eye closure, to prevent sight threatening complications. Regular topical lubricants throughout the day with thicker viscosity lubricant at night should be prescribed with taping of eye shut at night. Referral to ENT and ophthalmology should be considered in all cases of total facial paralysis.
Neuro-Ophthalmic Literature Review
Published in Neuro-Ophthalmology, 2022
David A. Bellows, Noel C. Y. Chan, John J. Chen, Hui-Chen Cheng, Peter W. MacIntosh, Michael S. Vaphiades, Konrad P. Weber, Xiaojun Zhang
This was a prospective study evaluating the change in Bell’s phenomenon after inferior and medial orbital wall decompression in 30 patients with TAO. Results were compared at baseline prior to surgery and six months postoperatively. The authors found that the distance of Bell’s phenomenon significantly decreased after surgery by an average of 3.25 ± 1.57 mm (p < .001). The adjusted Bell’s phenomenon was also noted to have worsened by 1.58 ± 2.13 mm (p < .001). Despite a significant reduction in exophthalmos after the surgery (24.3 ± 3.06 mm to 22.3 ± 2.27 mm, p < .001), the mean corneal stain score was not statistically different after the decompression.
Vertical Gaze Palsy Caused by Selective Unilateral Rostral Midbrain Infarction
Published in Neuro-Ophthalmology, 2018
Misato Yokose, Kohei Furuya, Masayuki Suzuki, Tadashi Ozawa, Younhee Kim, Kumiko Miura, Kosuke Matsuzono, Takafumi Mashiko, Mari Tada, Reiji Koide, Haruo Shimazaki, Tohru Matsuura, Shigeru Fujimoto
A 52-year-old Japanese woman was admitted to our hospital with a complaint of a one-day history of double vision and gait instability. She has a medical history of hypertension and hyperlipidaemia. Neurological examination on admission revealed upward and downward gaze palsy in voluntary saccadic and pursuit eye movements, slight blepharoptosis of the right eye, and a truncal ataxia (Figure 1). Her downward vestibulo-ocular reflex (VOR) was preserved, whereas no upward VOR was observed (Figure 1). Bell’s phenomenon was not detected. Her muscle strength, sensory abilities, and limb coordination were normal.
Congenital Fibrosis of Extraocular Muscles: A Systematic Review and Meta-Analysis
Published in Journal of Binocular Vision and Ocular Motility, 2023
Joshua M. Van Swol, Walter K. Myers, Shaun A. Nguyen, M. Edward Wilson
We also analyzed the materials used for frontalis slings. Of the 56 frontalis sling operations, 42 used autologous fascia lata, 12 used silicone rods, and 2 used stored fascia lata. Patients with absent Bell’s phenomenon are more likely to experience corneal complications than those with proper elevation of the eye with lid closure. In these cases, silicone rods are preferred over fascia lata in these patients to allow for easier revision. Moreover, elevating the lid only to the pupillary border is advised in patients with absent Bell’s phenomenon.12,15