10 research outputs found
Peripheral image quality in pseudophakic eyes
The purpose of this work was to evaluate peripheral image quality in the pseudophakic eye using computational, physical, and psychophysical methods. We designed and constructed a physical model of the pseudophakic human eye with realistic dimensions using a corneal phantom and a board-only camera that was pivoted around an axis that matched the anatomical center of a human retina, assuming a radius of curvature of 12 mm, while it was submersed in a 23.4 mm long water filled chamber to emulate human ocular axial length. We used this optical setup to perform direct recording of the point spread function (PSF) and the associated retinal images for a commercial intraocular lens (IOL). Additionally, psychophysical tests were carried out to investigate the impact of the off-axis astigmatism in peripheral visual performance, where spectacle-induced astigmatism simulated the pseudophakic conditions in healthy subjects. Our findings using the physical eye model confirm the existence of large amounts of astigmatism in the periphery of the pseudophakic eye. The psychophysical tests revealed a significant reduction of detection sensitivity in the peripheral visual field. The latter suggests that off-axis astigmatism in patients implanted with IOLs may have performance and safety implications for activities requiring efficient peripheral vision
Acute comitant esotropia after cataract surgery
A 52-year-old woman developed comitant esotropia after cataract surgery. The ocular history was significant for accommodative esotropia; preoperatively, she manifested peripheral fusion with central suppression. Immediately postoperatively, the patient was diplopic with comitant esotropia and was treated with extraocular muscle surgery. The appearance of horizontal strabismus after cataract surgery in patients with a history of accommodative esotropia, especially those with subnormal binocularity, is a possible complication that should be discussed with the patient. © 2002 ASCRS and ESCRS
Twelve years' continuous wear of the same therapeutic soft contact lens: a case report
Purpose. To describe a case of a patient who had worn the same
therapeutic soft contact lens (TSCL) continuously for twelve years,
since he had failed to attend normal follow-up visits.
Methods. Microbiological histological and scanning electron microscopic
(SEM) studies of conjunctiva, cornea and TSCL were done.
Results. Cultures were negative. Corneal histology revealed mild stromal
edema and mild epithelial parakeratosis. Corneal SEM was remarkable for
the preservation to some extent of normal corneal epithelial
specialization with microtricae and microvillae. SEM of the TSCL showed
a ruffed multi-layer surface with several cracks including different
types of cells.
Conclusions. The patient showed surprising tolerance to the continuous
wear of the same contact lens for 12 years
Relapsing polychondritis: A clinical review
Objective: This study comprehensively reviews the literature related to
relapsing polychondritis (RP).
Methods: A detailed search via MEDLINE (PubMed) was performed using
relapsing polychondritis as the key term. Relevant articles were
analyzed with a focus on history, epidemiology, etiology, pathogenesis,
clinical manifestations, diagnosis, treatment, and prognosis of RP.
Results: RP is a rare episodic and progressive inflammatory disease of
presumed autoimmune etiology first described in 1923, RP affects
cartilage in multiple organs, such as the ear, nose, larynx, trachea,
bronchi, and joints. In addition, it can affect proteoglycan-rich
tissues, such as the eyes, aorta, heart, and skin. The diagnosis of RP
is based on the presence of clinical criteria. A standardized
therapeutic protocol for RP has not been established. Nonsteroidal
anti-inflammatory drugs, dapsone and/or colchicine, may control disease
activity in some patients. In other patients, immunosuppressive drugs
and prednisone have been effective, RP is a potentially lethal disease;
pulmonary infection, systemic vasculitis, airway collapse, and renal
failure are the most common causes of death. Earlier studies indicate
survival rates between 70% at 4 years and 55% at 10 years. In a recent
study, a survival rate of 94% at 8 years may be due to improved medical
and surgical management.
Conclusions: RP is a rare, multisystemic, and potentially fatal disease.
The pathogenesis and optimal therapeutic approach to patients with RP is
poorly understood