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Dizziness
Published in Henry J. Woodford, Essential Geriatrics, 2022
Cerebellopontine angle tumours (e.g. acoustic neuroma) usually present with unilateral sensorineural hearing loss due to compression of the eighth nerve. The trigeminal nerve may also be affected causing facial numbness and loss of the corneal reflex. When vertigo occurs, it is usually a late feature.
Brain death and ethical issues
Published in Hemanshu Prabhakar, Charu Mahajan, Indu Kapoor, Essentials of Anesthesia for Neurotrauma, 2018
The corneal reflex assesses the pathway arising from the trigeminal nerve—from small unmyelinated pain fibers in the cornea—and the dorsal parts of facial nuclei in the pons, which determines contraction of the orbicularis oculi muscles when either cornea is touched. The corneal reflex is tested by gently touching the edge of the cornea with a cotton or tissue swab and observing the absence of a responsive blink.
Answers
Published in Calver Pang, Ibraz Hussain, John Mayberry, Pre-Clinical Medicine, 2017
Calver Pang, Ibraz Hussain, John Mayberry
This scenario describes the testing of the corneal reflex, which is an involuntary blinking of the eyelids elicited by stimulation of the cornea. The reflex is stimulated by the nasociliary branch of the ophthalmic branch of the trigeminal nerve (sensory response) and the temporal and zygomatic branch of the facial nerve (motor response).
The Prevalence of Refractive Errors and Visual Impairment among School Children in Brčko District, Bosnia and Herzegovina
Published in Seminars in Ophthalmology, 2018
Allen Popović-Beganović, Jasmin Zvorničanin, Vera Vrbljanac, Edita Zvorničanin
Ocular motility was evaluated by ophthalmologist with cover testing and observation of the corneal reflex at 0.5 and 4.0 meters. Tropias were categorized as exotropia, esotropia or vertical, with the degree of tropia measured using the corneal reflex (Hirschberg´s method). Pupils in both eyes were dilated with two drops of 1% cyclopentolate with an interval of 5 min. If a pupillary light reflex was still present after 20 min, a third drop was administered. Light reflex and pupil dilation were evaluated after additional 15 min. Cycloplegia was considered complete if the pupil was dilated to 6 mm or more and light reflex was absent. Refraction was performed in all children after cycloplegia by ophthalmologist, regardless of their visual acuity, using first streak retinoscopy (Heine Beta® 200 Retinoscope, HEINE Optotechnik Germany). Cycloplegic autorefraction was performed by optometrist using the autorefractor (Humphrey Zeiss ARK 599 Autorefractor Keratometer, Carl Zeiss Meditec AG), with calibration made at the beginning of each day using an eye model. At least eight representative values from the autorefractor were acquired for data analysis. Unreliable measurements were rejected and remeasured. The ophthalmologist evaluated the external eye and anterior segment (eyelid, conjunctiva, cornea, iris and pupil) using a slit lamp while the media and fundus were evaluated with direct and indirect ophthalmoscopic examination.
Effect of the use of dexmedetomidine as an adjuvant in peribulbar anesthesia in patients presented for vitreoretinal surgeries
Published in Egyptian Journal of Anaesthesia, 2018
Sameh Abdelkhalik Ahmed, Mohamad Gamal Elmawy, Amr Ahmed Magdy
Sensory block was assessed by the abolishment of corneal reflex to instillation of physiological drops on the cornea or conjunctiva. The onset of anesthesia was determined by the time interval from local anesthetics injection and loss of corneal reflex. The motor block was evaluated by asking the patient to open, close, and squeeze his eye (Lid Akinesia) and to move his eye globe in the four directions of the gaze (globe akinesia). The quality of akinesia was assessed through the use of akinesia score where 0=inability to move (total akinesia), 1=partial movement (partial akinesia), and 2=full movements (no akinesia). This score was used to assess both lid akinesia and globe akinesia in the four directions with the overall score of 10 [18]. The onset of lid akinesia was calculated from peribulbar injection to the partial loss of ability to open or squeeze eye lids, while, the onset of globe akinesia was estimated from the injection of the local anesthetic mixture and partial loss of movement of eye globe in the four cardinal directions. The surgery was considered to be optimal to be started when the patient had corneal anesthesia together with partial lid and globe akinesia. The optimal time to start the surgery was considered as the elapsed time between local anesthetics injection and satisfying the goals to start the surgery. The intraocular pressure was measured preoperatively and immediately before initiating the surgery with detection of number of patients with increase in the intraocular tension (increase intraocular pressure more than 25mmHg or by more than 10mmHg than the preoperative value)
Sinonasal Lymphoma Presenting as Cavernous Sinus Syndrome: Case Report and Review of the Literature
Published in Neuro-Ophthalmology, 2022
Noranida Abd Manan, May May Choo, Irina Effendi Tenang, Mimiwati Zahari
Anisocoria was present; the left pupil was 7 mm and unresponsive to light while the right pupil measured 3 mm with a normal pupillary light reflex (Figure 1). There was no relative afferent pupillary defect. The left eye had generalised limitation of eye movements in all directions of gaze. The right eye had limitation of abduction, dextroelevation and dextrodepression (Figure 2). The left corneal reflex was reduced and hypoaesthesia in the territory of the first and second divisions of the left trigeminal nerve was also present. Funduscopic examination was normal in both eyes. The general physical examination was otherwise unremarkable including no lymphadenopathy or hepato-splenomegaly.