【正】INTRODUCTION Femtosecond laser technology,introduced clinically for ophthalmic surgery as a technique for creating lamellar flaps in laser in situ keratomileusis(LASIK),has recently been developed into a tool fo...【正】INTRODUCTION Femtosecond laser technology,introduced clinically for ophthalmic surgery as a technique for creating lamellar flaps in laser in situ keratomileusis(LASIK),has recently been developed into a tool for cataract surgery.Preliminary experience for femtosecond laser-assisted cataract surgery show appropriate safety and efficacy,and possible advantage over conventional cataract surgery[1-4].The ability of the femtosecond laser to fragment the lens results in the need for less ultrasound energy to be expended inside the eye.Several studies indicate that less effective phacoemulsification time is needed to emulsify the lens展开更多
Many organisms have evolved an approximately 24-hour circadian rhythm that allows them to achieve internal physiological homeostasis with external environment.Suprachiasmatic nucleus(SCN) is the central pacemaker of...Many organisms have evolved an approximately 24-hour circadian rhythm that allows them to achieve internal physiological homeostasis with external environment.Suprachiasmatic nucleus(SCN) is the central pacemaker of circadian rhythm,and its activity is entrained to the external light-dark cycle.The SCN controls circadian rhythm through regulating the synthesis of melatonin by pineal gland via a multisynaptic pathway.Light,especially shortwavelength blue light,is the most potent environmental time cue in circadian photoentrainment.Recently,the discovery of a novel type of retinal photoreceptors,intrinsically photosensitive retinal ganglion cells,sheds light on the mechanism of circadian photoentrainment and raises concerns about the effect of ocular diseases on circadian system.With age,light transmittance is significantly decreased due to the aging of crystalline lens,thus possibly resulting in progressive loss of circadian photoreception.In the current review,we summarize the circadian physiology,highlight the important role of light in circadian rhythm regulation,discuss about the correlation between age-related cataract and sleep disorders,and compare the effect of blue light-filtering intraocular lenses(lOLs) and ultraviolet only filtering lOLs on circadian rhythm.展开更多
Although cataract surgery in posterior polar cataract is associated with posterior capsular rent and nucleus drop, by taking precautions the rate of complication can be decreased. The aim of this article is to review ...Although cataract surgery in posterior polar cataract is associated with posterior capsular rent and nucleus drop, by taking precautions the rate of complication can be decreased. The aim of this article is to review the etiology, pathogenesis, clinical features, and management of posterior polar cataract.展开更多
Background: Cataract surgery is the most frequently performed surgery worldwide. Posterior capsule rupture (PCR) remains one of the most common complications of cataract surgery and a major risk factor for poor visual...Background: Cataract surgery is the most frequently performed surgery worldwide. Posterior capsule rupture (PCR) remains one of the most common complications of cataract surgery and a major risk factor for poor visual outcomes. Cataract surgeries complicated by PCR and vitreous loss are managed with anterior vitrectomy at the time of surgery. However, the situation can be further complicated by dropping lens particles into the vitreous cavity necessitating a secondary pars plana vitrectomy (PPV). Purpose: To compare the visual outcomes and risk of rhegmatogenous retinal detachment (RRD) between eyes that required anterior vitrectomy (AV) alone for the management of vitreous loss and eyes that required AV and subsequent PPV for the management of dropped nuclear lens fragments (DNLF) following cataract surgery complicated by PCR in a tertiary care teaching hospital in Saudi Arabia. Methods: Medical records of patients in whom PCR occurred during phacoemulsification cataract surgery requiring AV or subsequent PPV for DNLF were retrospectively reviewed over a 6-year period from January 2016 to December 2021. Results: PCR occurred in 183 (2.3%) of 7757 consecutive eyes that underwent phacoemulsification cataract surgery during the study period. Seven eyes were excluded from analysis for missing data or short follow-up. Of the 176 eyes, 147 eyes (83.5%) were managed with AV alone, and the remaining 29 eyes (16.5%) underwent a secondary PPV for DNLF. After excluding eyes with pre-existing ocular pathology, final best-corrected visual acuity (BCVA) was similar in both groups with a mean of 0.32 logMAR (P = 0.99). Two of 147 eyes (1.4%) in the AV group developed RRD with poor final BCVA whereas none of the eyes in DNLF group developed RRD. Conclusion: The risk of RRD is lower in eyes that required PPV for DNLF than in eyes that were managed with AV alone following PCR during cataract surgery. The poor visual outcomes in eyes that suffered RRD underscore the importance of postoperative retinal examination and early detection of retinal breaks.展开更多
文摘【正】INTRODUCTION Femtosecond laser technology,introduced clinically for ophthalmic surgery as a technique for creating lamellar flaps in laser in situ keratomileusis(LASIK),has recently been developed into a tool for cataract surgery.Preliminary experience for femtosecond laser-assisted cataract surgery show appropriate safety and efficacy,and possible advantage over conventional cataract surgery[1-4].The ability of the femtosecond laser to fragment the lens results in the need for less ultrasound energy to be expended inside the eye.Several studies indicate that less effective phacoemulsification time is needed to emulsify the lens
文摘Many organisms have evolved an approximately 24-hour circadian rhythm that allows them to achieve internal physiological homeostasis with external environment.Suprachiasmatic nucleus(SCN) is the central pacemaker of circadian rhythm,and its activity is entrained to the external light-dark cycle.The SCN controls circadian rhythm through regulating the synthesis of melatonin by pineal gland via a multisynaptic pathway.Light,especially shortwavelength blue light,is the most potent environmental time cue in circadian photoentrainment.Recently,the discovery of a novel type of retinal photoreceptors,intrinsically photosensitive retinal ganglion cells,sheds light on the mechanism of circadian photoentrainment and raises concerns about the effect of ocular diseases on circadian system.With age,light transmittance is significantly decreased due to the aging of crystalline lens,thus possibly resulting in progressive loss of circadian photoreception.In the current review,we summarize the circadian physiology,highlight the important role of light in circadian rhythm regulation,discuss about the correlation between age-related cataract and sleep disorders,and compare the effect of blue light-filtering intraocular lenses(lOLs) and ultraviolet only filtering lOLs on circadian rhythm.
文摘Although cataract surgery in posterior polar cataract is associated with posterior capsular rent and nucleus drop, by taking precautions the rate of complication can be decreased. The aim of this article is to review the etiology, pathogenesis, clinical features, and management of posterior polar cataract.
文摘Background: Cataract surgery is the most frequently performed surgery worldwide. Posterior capsule rupture (PCR) remains one of the most common complications of cataract surgery and a major risk factor for poor visual outcomes. Cataract surgeries complicated by PCR and vitreous loss are managed with anterior vitrectomy at the time of surgery. However, the situation can be further complicated by dropping lens particles into the vitreous cavity necessitating a secondary pars plana vitrectomy (PPV). Purpose: To compare the visual outcomes and risk of rhegmatogenous retinal detachment (RRD) between eyes that required anterior vitrectomy (AV) alone for the management of vitreous loss and eyes that required AV and subsequent PPV for the management of dropped nuclear lens fragments (DNLF) following cataract surgery complicated by PCR in a tertiary care teaching hospital in Saudi Arabia. Methods: Medical records of patients in whom PCR occurred during phacoemulsification cataract surgery requiring AV or subsequent PPV for DNLF were retrospectively reviewed over a 6-year period from January 2016 to December 2021. Results: PCR occurred in 183 (2.3%) of 7757 consecutive eyes that underwent phacoemulsification cataract surgery during the study period. Seven eyes were excluded from analysis for missing data or short follow-up. Of the 176 eyes, 147 eyes (83.5%) were managed with AV alone, and the remaining 29 eyes (16.5%) underwent a secondary PPV for DNLF. After excluding eyes with pre-existing ocular pathology, final best-corrected visual acuity (BCVA) was similar in both groups with a mean of 0.32 logMAR (P = 0.99). Two of 147 eyes (1.4%) in the AV group developed RRD with poor final BCVA whereas none of the eyes in DNLF group developed RRD. Conclusion: The risk of RRD is lower in eyes that required PPV for DNLF than in eyes that were managed with AV alone following PCR during cataract surgery. The poor visual outcomes in eyes that suffered RRD underscore the importance of postoperative retinal examination and early detection of retinal breaks.