Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rapid recognition and appropriate therapy will prevent or remediate most of the complications occurring in children after cataract aspiration and IOL implantation. Some of the complications of pediatric IOL implantations are related to the increased scleral pliability and decreased rigidity which predispose scleral collapse, vitreous loss, flat anterior chamber and corneal endothelial damage. A second group of complications is associated with the enhanced inflammatory and fibrotic responses peculiar to a child's eye. This group includes operative striate keratitis and iridocyclitis, late IOL precipitates, secondary and postpseudophakos membranes, iris erosion and synechiae formation, and IOL tilt and displacement. Although the intraocular lens is a possible means of visual rehabilitation for children with traumatic cataracts or unilateral infantile cataracts, its long-term risk/benefit ratio must still stand the test of time.
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PMID:Complications of implant surgery in children. 37 20

The late complications of corneo-scleral wound healing after the 15th postoperative day were recorded in 108 routine adult cataract operations using 7-0 polyglycolic acid (Dexon) sutures and compared with 80 routine adult cataract operations using 9-0 monofilament nylon (9-10 Ethilon Nylon) sutures. In 37 eyes of the 7-0 Dexon group filtrating blebs, gaping of the corneoscleral wound, anterior chamber collapse, or decrease in the intraocular pressure were observed compared with one filtrating bleb in the 9-0 nylon group. The majority of late complications occurred 22 to 42 days after surgery. Ten filtrating blebs remained after a 5 months' follow-up period. The most probable cause of the late complications in corneo-scleral wound healing was discussed.
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PMID:Late complications of 7-0 polyglycolic (Dexon) sutures in cataract surgery. 41 74

Retinal detachments occur in up to 3.6% of pseudophakic patients. The intraocular lens makes it hard to see the peripheral fundus but the small pupil ophthalmoscope is a valuable help. The functional and anatomic success rates after operation are about 5% less than those of patients with aphakic retinal detachments matched for age and sex. I present fifteen cases of pseudophakic detachment. Any manipulation likely to induce contact between lens and cornea such as collapse of the globe after drainage of fluid or gas injections should be avoided. Careful examination of the fundus before and after cataract extraction and careful selection of paients for lens implantation are the only means of reducing the incidence of retinal detachment.
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PMID:Retinal detachment and pseudophakia. 55 Sep 18

The unopened eye maintains a relatively stable spherical contour due to the expansile influence of the intraocular pressure. When the eye is opened this expansile pressure is lost and some degree of collapse of the scleral shell ensues. In eyes with a relatively flaccid sclera an anterior segment incision may induce significant reduction in the volume of the posterior segment of the globe. During intracapsular cataract extraction on such eyes, scleral collapse can cause anterior displacement of the lens and iris when the eye is opened and vitreous loss as soon as the lens is extracted. Scleral collapse tends to occur during intraocular surgery on previously aphakic eyes. In this situation it may become difficult to achieve a vitreous-free anterior sement by open sky vitrectomy. Metallic scleral supporters prevent inward collapse of that portion of the sclera to which they are attached. They do not prevent downward collapse of the posterior sclera shell. Upward traction is required to prevent the downward component of scleral collapse. A system for controlled suspension of the globe during intraocular surgery has been devised and used in a variety of surgical procedures. The apparatus is simple and it does help to minimize downward scleral collapse. It does not prevent scleral identation or distortion by external forces and cannot substitute for inadequate anesthesia and akinesia or faulty surgical technique.
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PMID:Suspension of the globe during intraocular surgery. 75 77

Examinations of 87 patients with different positions of the eyeball in the orbit have revealed that if the eyeball sinks even slightly deeper in the orbit than normally, collapse of the cornea is observed during cataract extraction and ciliary-choroid detachment develops during the postoperative period. If the eyeball protrudes forward no corneal collapse or ciliary-choroid detachment occur.
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PMID:[Results of exophthalmometry. Incidence of ciliary-choroid detachment]. 223 20

Structural changes in the lens and vitreous body exposed to short-pulse Nd:YAG Q-switching laser were under study. The laser was focussed in the lens nucleus or vitreous center plane. A pulse energy was 7.1-9.3 mJ, with a total of 75-100 pulses. Cataract development was induced via the formation of cavities with the guidance spot focal plane localized in the lens nucleus plane. When the focus was in the vitreous body and the laser operated in a similar energy mode, great numbers of small cavities rapidly formed, this evidencing a shock wave propagation. Specific and structural conformational changes in the lens and vitreous protein molecules were detected by nitrate quenching of the triptophane amino acid residue fluorescence. Laser exposure was found to reduce triptophanile availability for nitrates, this evidencing protein complexes aggregation (collapse); besides, laser exposure essentially increased the amino acid residue quenching constants, which fact pointed to a decreased density of the vitreous collagen and lens crystalline negative charges (increased hydratation). These findings permit a conclusion that the shifts connected with injury to the vitreous body, with macular edema, or with detachment of the retina after exposure to Nd:YAG laser may be due to collapse of the vitreous gel liquified components.
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PMID:[Photo damage to the eye in exposure to the radiation from a Nd:YAG Q-switching laser: the physicochemical structural changes to the crystalline lens and the vitreous body]. 237 33

Two human eyes that had undergone intracapsular cataract extraction were perfused with cationized ferritin. In both eyes segmental areas of trabecular meshwork collapse were demonstrated superiorly, adjacent to the cataract incision. Electron-microscopic study of these regions disclosed no labeling of the trabecular beams and trabecular spaces, suggesting impermeability to aqueous flow. In other regions, a diffuse labeling with cationized ferritin was demonstrated throughout the trabecular spaces, indicating aqueous flowthrough. Use of corneoscleral sutures may cause trabecular collapse and impermeability. When the collapse is extensive, subsequent increase in intraocular pressure may follow.
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PMID:Alteration of trabecular aqueous flow after cataract extraction. 344 98

This thesis presents the results of a study of 384 eyes of 192 patients with a mean age of 39.1 years who presented with typical retinitis pigmentosa. The major findings are outlined below, together with suggested hypotheses: Cataract was found in 46.4% of the eyes. Among these, 93.6% showed posterior subcapsular opacification. The incidence of cataract increased with age. The vitreous degeneration that is characteristic of the RP syndrome and begins in childhood was described as showing dust-like, particulate matter throughout the gel; posterior vitreous separation; formation of a posterior matrix of coarse, white, interconnected strands and opacities; and final collapse of the residual gel. Ultrastructural studies of vitreous material from eight eyes revealed that the particles were isolated pigment granules and the coarse strands were composed of condensed collagen fibers. Notwithstanding the vitreous degeneration and prevalence of myopia in RP, neurosensory retinal breaks and/or rhegmatogenous detachment were found in only 7 (1.8%) of the 384 eyes studied. Premature separation of the vitreous from the retina, absence of lattice retinal degeneration, and perhaps a stronger than normal RPE-neurosensory retinal bond are thought to be possible protective factors. Rather than searching for a "toxin," elaborated by diseased retina, that causes vitreous degeneration and cataract formation, it is suggested that the ocular media be studied for an absence of moieties that are normally produced by healthy retina for vitreous and lens maintenance. The classic criteria for diagnosis of RP were met by 96.3% of eyes that showed retinal vascular attenuation and by 52.0% that showed pallor of the optic disc. Less frequent manifestations included solitary retinal hemorrhage, peripheral microaneurysms, telangiectasia, and fluorescein leakage at the macula and disc. Seven additional cases with a Coats'-like retinal detachment were added to the 14 already presented in the literature. Two of the seven had autosomal dominant RP, the first such cases reported. The vascular malformations and detachments were most often inferior. Unlike typical Coats' syndrome, the condition was usually bilateral, showed no sex preference, and appeared to affect older individuals.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Retinitis pigmentosa: clinical observations and correlations. 667 82

A new combined scleral ring and blepharostat for cataract surgery is introduced. It is a modification of the McNeil-Goldman ring blepharostat. The new ring-blepharostat provides protection against anterior scleral collapse, separates the lids and fixates the globe. It is recommended for use in all high risk cataract surgery.
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PMID:A new combined scleral ring-blepharostat for cataract surgery. 699 11

The intraocular pressure was measured at 5-minute intervals with a Perkins applanation tonometer in 5 patients undergoing routine dacryocystorhinostomy under low-tension anaesthesia with a continuous intravenous infusion of trimetaphan (Arfonad), the systolic pressure being maintained at 66 mmHg. Twelve patients undergoing cataract surgery under the same premedication and anaesthesia but in whom the systemic blood pressure was maintained at normal levels served as controls. A sudden and dramatic lowering of the intraocular pressure to very low levels was noted when the systolic blood pressure was reduced to 60 mmHg. It seems likely that a collapse of the choroidal circulation rather than a decreased aqueous formation due to low perfusion pressure is the most likely cause of the sudden lowering of intraocular pressure.
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PMID:Effect on the intraocular pressure of hypotensive anaesthesia with intravenous trimetaphan. 712 18


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