pupillary block


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pupillary block

increased resistance to flow of aqueous humor through the pupil from the posterior chamber to the anterior chamber, leading to anterior bowing of the peripheral iris over the trabecular meshwork and to angle-closure glaucoma.

pu·pil·lar·y block

(pyū'pi-lār-ē blok)
Increased resistance to flow of aqueous humor through the pupil from the posterior chamber to the anterior chamber, leading to anterior bowing of the peripheral iris over the trabecular meshwork and to angle-closure glaucoma

pupillary block 

A blockage of the normal flow of aqueous humour from the posterior to the anterior chamber of the eye. It may be caused by a posterior annular synechia occurring during anterior uveitis, by luxation of the lens anteriorly occluding the pupil, or by adhesion of the iris to the vitreous or to the posterior capsule following extracapsular cataract extraction (called aphakic pupillary block). It may produce an attack of acute angle-closure glaucoma as the iris may be pushed forward blocking the drainage angle. Syn. pupil block. See iris bombé; seclusio pupillae.
References in periodicals archive ?
Extremes of vault are risk factors for complications such as cataract, pigment dispersion, pupillary block, and glaucoma.
In the contralateral eyes of the enrolled patients, either trabeculectomy or laser peripheral iridoctomy was performed to eliminate reverse pupillary block, and the iris recovered to flat or regular.
Anterior chamber (AC), although absent in periphery, proved normal depth centrally (important element for primary causes of angle closure and not secondary related to pupillary block in anterior uveitis).
The post operative complications were posterior capsular opacification (PCO) in 153 eyes, pupillary capture of the optic of the IOL (pup cap) in 34 eyes, post operative uveitis (p o uveitis) in 26 eyes, corneal decompensation (corn decom) in three eyes, vitreous hemorrhage (vit h'age) in two eyes, secondary glaucoma (sec gl) in two eyes, decentred IOL (dec IOL) in two eyes, pupillary block glaucoma (pup bl gl) in two eyes and retinal detachment (RD) in one eye.
(2) The iris in these eyes can start to bow posteriorly and chafe against the lens zonules--a situation known as 'reverse pupillary block.' This rubbing can then lead to the release of pigment from the iris into the anterior chamber, giving rise to a classic triad of clinical signs.
Importantly, if pupillary block and elevated intraocular pressure associated with dilation can be avoided, a trained nonmedical personnel can safely capture images to use them in telemedicine applications, especially in areas without ophthalmologists.
Medical management consisting of topical steroids, antiglaucoma drugs, analgesics and in cases of pupillary block, a mydriatic was used.
(2) Spherical lens may lead to pupillary block and secondary angle-closure glaucoma.
Given the presence of anterior uveitis and the markedly shallow anterior chamber in this owl, potential mechanisms for ocular hypertension were considered to be altered aqueous humor flow within the trabecular meshwork (secondary to anterior uveitis) or at the pupil (caused by pupillary block), aqueous misdirection and expansion of the vitreous body (malignant glaucoma), or some combination of these mechanisms, as is often the case in cats.
In the absence of capsular support; anterior chamber lenses iris fixated lenses and scleral fixated intraocular lenses may be considered.12 The placement of IOL in the posterior chamber rather than anterior or iris fixated lenses reduces the risk of various complications like keratopathy damage to anterior chamber angle structure pupillary block glaucoma hyphema uveitis iris chafing dislocationandpseudophakodonesis.3
One theory of PDS is that there is a pressure differential between the anterior and posterior chambers generating 'reverse' pupillary block by bowing the iris backwards.