The influence of eye muscle surgery on shape and relative orientation of displacement planes: Indirect evidence for neural control of 3D eye movements

AbstractRapid eye movements (REM) are characteristic of the eponymous phase of sleep, yet the underlying motor commands remain an enigma. Here, we identified a cluster of Calbindin-D28K-expressing neurons in the Nucleus papilio (NPCalb), located in the dorsal paragigantocellular nucleus, which are active during REM sleep and project to the three contralateral eye-muscle nuclei. The firing of opto-tagged NPCalb neurons is augmented prior to the onset of eye movements during REM sleep. Optogenetic activation of NPCalb neurons triggers eye movements selectively during REM sleep, while their genetic ablation or optogenetic silencing suppresses them. None of these perturbations led to a change in the duration of REM sleep episodes. Our study provides the first evidence for a brainstem premotor command contributing to the control of eye movements selectively during REM sleep in the mammalian brain.

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Endoscopic Orbital Decompression for Graves’ Ophthalmopathy

American Journal of Rhinology ◽

10.1177/194589240501900613 ◽

2005 ◽

Vol 19 (6) ◽

pp. 603-606 ◽

Cited By ~ 29

Author(s):

Jan L. Kasperbauer ◽

Lucinda Hinkley

Keyword(s):

Optic Neuropathy ◽

Cerebrospinal Fluid Leak ◽

Hospital Length ◽

Hospital Length Of Stay ◽

Orbital Decompression ◽

Orbital Cavity ◽

Eye Muscle ◽

Graves Ophthalmopathy ◽

Fluid Leak ◽

Eye Muscle Surgery

Background Graves’ ophthalmopathy generates a volume excess for the orbital cavity, which may produce proptosis, pain, exposure keratitis, diplopia, and optic neuropathy. Endoscopic orbital decompression expands the orbital cavity into the ethmoid cavity and medial maxillary sinus. This retrospective study documents the outcomes after endoscopic orbital decompression for patients with Graves’ ophthalmopathy. Methods Data collected included demographic information, symptom resolution, complications related to the surgery, reduction in proptosis, subsequent need for eye muscle surgery, and hospital length of stay. Between July 1989 and April 2003, 62 patients were referred for endoscopic orbital decompression (often unilateral). Results Three patients refused use of their medical records for research purposes. Seventy percent were women; the average age of the study group was 49 years. Preoperatively, 63% of the patients had diplopia and optic neuropathy was noted in 27%. Two patients had a cerebrospinal fluid leak identified and managed during the decompression. No postoperative leaks occurred. Twenty-five percent of patients did not require eye muscle surgery. Forty-eight percent of the patients underwent one procedure to manage diplopia. The average reduction in proptosis was 2.5 mm. Fifty-four percent were managed as an outpatient and 27% underwent a 23-hour observation period. Conclusion This data supports the safety, efficiency, and efficacy of endoscopic orbital decompression for unilateral and bilateral Graves’ ophthalmopathy. Eye muscle surgery frequently will be required to manage diplopia after decompression. (American Journal of Rhinology 19, 603–606, 2005)

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Eye Muscle Surgery: Basic Data, Operative Techniques, Surgical Strategy

American Orthoptic Journal ◽

10.3368/aoj.52.1.121-a ◽

2002 ◽

Vol 52 (1) ◽

pp. 121-122

Keyword(s):

Surgical Strategy ◽

Basic Data ◽

Operative Techniques ◽

Eye Muscle ◽

Eye Muscle Surgery

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Central Positional Nystagmus Simulated by a Mathematical Ocular Motor Model of Otolith-Dependent Modification of Listing's Plane

Journal of Neurophysiology ◽

10.1152/jn.2001.86.4.1546 ◽

2001 ◽

Vol 86 (4) ◽

pp. 1546-1554 ◽

Cited By ~ 30

Author(s):

S. Glasauer ◽

M. Dieterich ◽

Th. Brandt

Keyword(s):

Eye Movements ◽

Neural Control ◽

Position Control ◽

Three Dimensional ◽

Head Tilt ◽

Eye Position ◽

Positional Nystagmus ◽

Listing's Plane ◽

Head Positions ◽

Listing’S Plane

To find an explanation of the mechanisms of central positional nystagmus in neurological patients with posterior fossa lesions, we developed a three-dimensional (3-D) mathematical model to simulate head position-dependent changes in eye position control relative to gravity. This required a model implementation of saccadic burst generation, of the neural velocity to eye position integrator, which includes the experimentally demonstrated leakage in the torsional component, and of otolith-dependent neural control of Listing's plane. The validity of the model was first tested by simulating saccadic eye movements in different head positions. Then the model was used to simulate central positional nystagmus in off-vertical head positions. The model simulated lesions of assumed otolith inputs to the burst generator or the neural integrator, both of which resulted in different types of torsional-vertical nystagmus that only occurred during head tilt in roll plane. The model data qualitatively fit clinical observations of central positional nystagmus. Quantitative comparison with patient data were not possible, since no 3-D analyses of eye movements in various head positions have been reported in the literature on patients with positional nystagmus. The present model, prompted by an open clinical question, proposes a new hypothesis about the generation of pathological nystagmus and about neural control of Listing's plane.

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