Purpose: A previous study demonstrated upper eyelid retraction synchronized with pupil dilation following a transition from photopic to scotopic conditions. The current study aimed to evaluate the role of Müller's muscle as the efferent arm of this suggested reflex arc.
Methods: A video scan of both eyes of patients with unilateral Horner syndrome was performed using optical coherence tomography infra-red mode to document the transition between photopic and scotopic conditions. The affected side with sympathetic denervation was the study group, whereas the contralateral unaffected side of the same patients served as the control group. The pupil diameter, upper eyelid margin-to-reflex distance 1, lower eyelid margin-to-reflex distance 2, and vertical palpebral fissure height were measured. The control group was compared to the healthy subjects of a previous study to verify any compensatory changes to the side contralateral to denervation.
Results: Ten patients with unilateral Horner Syndrome were included in the study. Transitioning from photopic to scotopic conditions, the mean change in margin-to-reflex distance 1 in the study and control groups was 315 ± 276 µm (P < 0.05) and 723 ± 432 µm (P = 0.005), respectively. Margin-to-reflex distance 1 and palpebral fissure height were significantly higher in the control group both in photopic (P = 0.005 and P = 0.017, respectively) and scotopic conditions (P = 0.005 and P = 0.007, respectively). The change in margin-to-reflex distance 1 and palpebral fissure height following the transition from light to dark was significantly greater in the control group (P = 0.022).
Conclusions: Reflexive eyelid retraction following a transition from photopic to scotopic conditions was significantly diminished in eyelids with sympathetic denervation compared with the unaffected contralateral side of the same patients. This study provides further evidence that the sympathetically innervated Müller's muscle serves as the efferent arm of this reflex.
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http://dx.doi.org/10.1167/iovs.64.14.35 | DOI Listing |
Am J Ophthalmol
December 2024
Department of Urology, Assoc. Prof. M.D., Hitit University Erol Olçok Education and Research Hospital, Çorum, Turkey.
Purpose: To investigate the effect of tamsulosin on iris morphology, ciliary muscle thickness (CMT), pupil diameter (PD), and pupil responses to light using anterior segment optical coherence tomography and corneal topography.
Design: Prospective clinical before-and-after study METHODS: The right eyes of 43 patients with newly diagnosed benign prostatic hyperplasia were included in this study. Iris dilator muscle region (DMR) thickness, sphincter muscle region (SMR) thickness, DMR/SMR ratio, PD (scotopic, mesopic and photopic light conditions), CMT1(1 mm posterior to the scleral spur), CMT2(2 mm posterior to the scleral spur), CMT3(3 mm posterior to the scleral spur) and anterior chamber depth(ACD) were measured before and after dilation.
Eye Contact Lens
December 2024
Cornea and Laser Eye Institute-CLEI Center for Keratoconus (J.D.G., B.S., T.P., C.E., P.S.H., S.A.G.), Teaneck, NJ; Department of Ophthalmology (J.D.G., D.K., P.S.H., S.A.G.), Rutgers-New Jersey Medical School, Newark, NJ; TX; OVITZ Corporation (N.B., J.W.), Rochester, NY; College of Optometry (G.Y.), University of Houston, Houston, TX.
Purpose: To report interim results of a single center, randomized, double-blind, crossover-controlled clinical trial comparing wavefront-guided (wfg) scleral lenses (SLs) to traditional scleral lenses (tSLs) for patients with a history of irregular corneal astigmatism (ICA).
Methods: Thirty-one ICA eyes of 18 participants were reviewed, 23 with keratoconus, six postcorneal refractive ectasia, and two postpenetrating keratoplasty. Patients with corneal or lens opacities were not excluded from participating.
Invest Ophthalmol Vis Sci
November 2024
Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, Japan.
Exp Eye Res
December 2024
Departamento de Física Aplicada, Universidad de Zaragoza, 50009, Zaragoza, Spain; Aragon Institute for Health Research (IIS Aragon), 50009, Zaragoza, Spain. Electronic address:
Retinal morphology, specifically in its curvature, and ocular aberrations change when the eye adapts to different lighting conditions, including photopic, scotopic, mesopic, blue light, and red light. Sixty healthy young subjects with refractive error less than ±4.00 D of sphere and 3.
View Article and Find Full Text PDFFront Neurosci
September 2024
fMRI Unit, Department of Neurology, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
High-level visual functions such as reading and face recognition rely on global processes, which are often insensitive to high spatial frequencies. However, it is unknown whether a sharp cone signal is necessary for the development of these skills or whether a blurry rod signal is sufficient. CNGA3/B3-achromatopsia is a congenital disease stemming from cone dysfunction, leading to rod-only vision characterized by nystagmus, impaired acuity, and complete color blindness.
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