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In a case-control study of 212 white patients with primary melanocytic tumors of the iris and two control groups, contingency tables were used to evaluate the distribution of iris color. We found a strong association between light iris color (blue, gray, or green) and the presence of iris melanocytic lesions (P less than .001 by chi 2).
The pre- and postjunctional affinity constants of a series of muscarinic antagonists were determined in guinea pig and rabbit irises. Field stimulation-evoked [3H]noradrenaline release from superfused isolated irises was concentration dependently inhibited by (+/-)-methacholine, confirming the presence on the iris noradrenergic nerves of prejunctional inhibitory muscarinic receptors. The affinity constants of the antagonists at the pre- and postjunctional receptors are compatible with the coexistence in the iris of two different M2 receptors: the cardiac (M2 alpha) subtype on the noradrenergic nerves and the smooth muscle (M2 beta) subtype on the iris sphincter muscle. The rank order of potency of the antagonists studied at the prejunctional site was: atropine greater than himbacine greater than AF-DX 116 greater than pirenzepine greater than hexahydrosiladifenidol. The order of potency at the postjunctional receptors mediating the methacholine-induced isotonic contraction of the isolated rabbit iris sphincter was: atropine greater than hexahydrosiladifenidol greater than pirenzepine greater than himbacine greater than AF-DX 116.
Progressive essential iris atrophy, Chandler's syndrome, and the iris nevus (Cogan-Reese) syndrome are considered to be variations of a single disease process, which is characterized by abnormalities of the cornea, anterior chamber angle, and iris. In each variation, the typical patient is a white woman with unilateral disease, negative family history, and an onset of symptoms in early to middle adulthood. Since the membrane theory of Campbell suggests that the disease is a fundamental abnormality of the corneal endothelium, rather than the iris, the term "iridocorneal endothelial syndrome," as proposed by Yanoff, may be an appropriate inclusive term for the spectrum of disease, although further study of the pathogenesis is needed. For each variation of the disease, corneal edema and secondary glucoma are both treated primarily by medical or surgical reduction of the intraocular pressure, although penetrating keratoplasty is occasionally required for cases with advanced corneal edema.
Iris prolapse has become an unusual and generally benign event in routine cataract surgery using endocapsular phacoemulsification techniques. We operated on the second eye of a patient with hyperopia whose first eye surgery in our care had been uneventful. In the second eye, as soon as the phaco incision was made and hydrodissection begun through the primary incision, the iris repeatedly prolapsed through the incision. This was managed definitively by applying iris hooks, 1 at each side of the primary incision, to the pupillary border so the prolapsing iris was held peripherally in the anterior chamber and under modest tension.
PURPOSE: To study aqueous flare longitudinally in patients with Fuchs' heterochromic uveitis (FHU) and for comparison in another group with iris atrophy (non FHU). METHODS: A new laser flare meter was used. Iris angiography was performed in most FHU patients. RESULTS: The flare values in the affected eyes in the FHU group were always higher compared to the normal eyes and rather constant over time. Cataract surgery did not permanently change the flare values. Systemic - but not local steroid therapy caused normalization of the flare. Iris angiography displayed leakage in all FHU eyes. Leakage from original vessels dominated although some newly-formed leaking vessels were observed. CONCLUSIONS: The results support the notion that FHU is a low grade, chronic, stable disease. Leaking iris vessels, original or newly-formed, are probably the source of the increased flare. Our hypothesis is that inflammation plays a major part. Atrophy per se does not enhance flare.
It is well known that urodeles have the most powerful regenerative capacities among vertebrates, but there is little realisation that they are extremely resistant to spontaneous or chemically induced tumours. Regeneration and carcinogenesis have been considered to be two sides of the same mechanism. Since antagonism between regeneration and carcinogenesis was expected in previous studies, the present study was intended to clarify this relationship in greater detail by changing the amounts of carcinogen stepwise. When 1 microliter nickel subsulfide solution was administered in various amounts (1 microgram/microliter approximately 40 micrograms/microliter) into lentectomized newt eyes, the delay of initiation in lens regeneration for 6 months and an increased inhibition rate of lens regeneration at 6 months were observed in proportion to the increase in carcinogen dosage. The tumour production rate increased in accordance with the increase in the amounts of carcinogen. The conspicuous result obtained in the present study was that lens regeneration from dorsal iris and tumour induction from ventral iris occurred simultaneously in the same eye after administration of moderate amounts (10 micrograms/microliter) of carcinogen. These data clearly indicated that the regenerating dorsal iris is persistently resistant to carcinogen, whereas the ventral iris, which cannot regenerate lens, is susceptible to tumour induction. This strongly suggests that the lens regeneration system in the newt has special advantages for research on the relationship between regeneration and carcinogenesis.
Fourteen eyes underwent cataract operation and implantation of an iris fixated (Medallion) pseudophakos. Eleven had an uncomplicated per- and post-operative course (group 1), 3 had a subluxation of the lens implant (group 2). The control group (group 3) consisted of the 14 contralateral eyes from group 1 and 2. Two cadaver eyes had a similar lens implanted (group 4). Groups 1-3 were investigated by bilateral simultaneous iris fluorescein angiography and retroiridal stereo transillumination photography. In group 1, one case with pupillary and diffuse semiperipheral leakage areas was observed, in a clinically healthy eye 15 months after the operation. An other one had some leakage at the pupillary border, but not in the area of contact with the loops. Rubbing between iris surface and some parts of the lens did not provoke local leakage. No new vessel formation was found. Pigment layer defects were observed in every operated eye, but no leakage was related to them except in the two pupillary areas mentioned. Mayor pigment defects did not progress in a quiet eye. The iris seems to be to some degree resistant to contact with the parts of the intraocular lens implant.
In order to know the correlation of a drug with high affinity to melanin in the iris ciliary body with the amount of melanin contained in the iris ciliary tissues, an in vivo study was performed on pigmented rabbits with brown or blue irises and albino rabbits. The melanin concentrations in the iris ciliary bodies of pigmented rabbits with brown and blue irises and nonpigmented rabbit eyes with whitish irises were determined. The mean concentrations of melanin in the eyes with brown-, blue- and whitish-colored irises were 47.43, 34.73 and below 0.2 microgram/mg tissue, respectively. The amount of sparfloxacin uptake in the iris ciliary bodies of eyes with brown, blue and whitish irises administered as 40 microliters of 0.3% solution 5 times every 5 min was 15.46 +/- 2.07, 8.53 +/- 1.87 and 1.9 micrograms/g, respectively. The results may be useful for intraocular drug dynamics studies.
Autoimmune disease has been suspected in some cases of human uveitis. The initiating event has been thought to be injury and/or infection. To investigate the effect of injury on the uvea and on the immune apparatus rabbits and guinea pigs were subjected to various repeated iris insults, including implantation of autologous iris tissue into the anterior chamber of the contralateral eye. Of the procedures employed only iridectomy and insertion of iris produced some anterior chamber clouding, which was only slightly increased on repetition of the procedure; 76% of these animals failed to produce circulating CF antibodies. No local CF antibodies in the anterior chamber fluid nor increases in fluorescent antibodes in sections of the eyes could be detected. None of the animals tested developed skin hypersensitivity to homologous uveal antigen. None of the other traumatic procedures, which included repeated insertions of plastic into the anterior chamber, produced uveitis manifested clinically or by histological examination, circulating or local humoral antibodies, nor increases in fluorescent antibodies in the tissues of the eye. Introduction of antiuveal antibody into the anterior chamber also failed to produce uveitis. It can be concluded from these experiments that simple, repeated injury to the iris is not sufficient to elicit an autoimmune response under the conditions tested.
PURPOSE: To report an ocular side effect of topical latanoprost therapy. DESIGN: Single interventional case report. METHODS: A 73-year-old woman on latanoprost for primary open-angle glaucoma developed an iris cyst simulating an iris melanoma. RESULTS: The lesion disappeared over 8 weeks when latanoprost was stopped. CONCLUSIONS: In managing patients with iris-pigmented lesions, the list of medications should be reviewed. If the patient takes latanoprost, a trial off latanoprost is warranted.
Seven cases are reported, believed to be the first in the literature, in which iris nodules are verified in the complete spectrum of essential iris atrophies. This feature appears late in the course of the disease as small yellow nodules that progressively increase in number and gradually become dark brown. The differential diagnosis of multiple iris nodules includes neurofibromatosis, melanomas, inflammatory nodules, and developmental anomalies such as iridocorneal dysgenesis.
The findings in iris fluorescein angiograms of 48 eyes with central retinal vein occlusion (CRVO) were correlated with the predominant retinal vascular response. In 24 eyes with the non-ischaemic type of CRVO there were no or only minimal iris vessel changes, whereas in all 24 eyes with ischaemic type of CRVO there was iris vessel dilatation and leakage with or without neovascularisation. These findings support the hypothesis that hypoxic retina may be a cause of rubeosis iridis in CRVO.
We developed a new micro-iris retractor to achieve temporary intraoperative pupillary mydriasis in selected eyes undergoing pars plana vitreous surgery. The micro-iris retractor and its use were compared with previous methods for obtaining adequate intraoperative pupillary dilation.
A 32-year-old black man had a deeply pigmented anterior uveal lesion that was indenting and subluxing the lens. The mass was successfully removed by a sector iridectomy and diagnosed histologically as an adenoma of the iris pigment epithelium. Although this rare tumor is sometimes misdiagnosed clinically as a malignant melanoma or iris cyst, it has distinctive clinical features which should differentiate it from these other entities.
The capacity of IRIP, a type-1 ribosome-inactivating protein (RIP) isolated from the bulbs of Iris hollandica, to bind specific DNA sequences from a mixture of approx. 200 bp (average length) fragments of total genomic DNA from Iris genome was studied. Fragments that were preferentially bound by IRIP were enriched by several cycles of affinity binding and PCR, and were cloned and sequenced. The selected DNA fragments do not share conserved sequences, indicating that IRIP does not bind DNA fragments in a strictly sequence-specific manner. According to sequence analysis, most IRIP-bound fragments contain one or more possible free energy-stable hairpin structure(s) in their secondary structure, which may be the basis for recognition between IRIP and these DNA fragments. Some, but not all, DNA fragments moderately lower the RNA N-glycosidase activity of IRIP towards rabbit reticulocyte lysate ribosomes. IRIP does not remove adenines from the binding fragments, which implies that it does not act as a polynucleotide:adenosine glycosidase towards these DNA fragments. The selective binding of IRIP to conspecific DNA fragments is also discussed in view of the novel concept that RIPs may act as DNA-binding proteins with a regulatory activity on gene expression.
Somatic embryos of black iris (Iris nigricans) were cryopreserved using encapsulation-dehydration. Embryos size of 2-4 mm gave the highest survival after cryopreservation. Preculturing embryos on medium containing 0.75 M sucrose for 3 d at 22 degree C, then at 30 degree C for 1 d ensured maximum survival (60%). Viable embryos were brown in color after cryopreservation and during early recovery while dead ones where light brown or creamy. The first sign of regrowth was noted after 15 d. The final regrowth percentage of living embryo was 90% after 35 d. Only 10% of the embryos in all treatments showed secondary embryogenesis. Direct sowing in vivo of cryopreserved embryos was not successful in achieving germination.
Iris monkeys resistant to repeated infections with B. malayi were subjected to immunosuppression by treatment with cortisone. Degree of immunosuppression was measured by: (a) blood counts, (b) lymphocyte transformation to mitogens and (c) immunofluorescent antibody to microfilarial antigens. Attempts were made to infect such immunosuppressed animals with B. malayi. No microfilariae were detected in the blood of any of the Iris monkeys during the 6 months of study. There was a sharp drop in the percentages of lymphocytes, but a rise in neutrophil counts during the first week of cortisone administration. Treatment with cortisone did not alter the antibody titres. The significance of this line of approach in the understanding of filarial resistance is discussed.
The most abundant protein of Iris bulbs has been identified as a type 1 ribosome-inactivating protein (RIP). Analysis of the purified proteins and molecular cloning of the corresponding cDNAs demonstrated that this type 1 RIP is a mixture of three isoforms that exhibit a high degree of sequence identity and have similar, though not identical, ribosome-inactivating and polynucleotide:adenosine glycosidase activities. The accumulation of large quantities of type 1 RIP in a vegetative storage organ suggests that this presumed defence-related protein also plays a role in the nitrogen-storage metabolism of the bulb.