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At least 19 recordsLinked to original sources
PubMed2006

Modified flexible iris retractor to retract superior iris and support inferior capsule in eyes with iris coloboma and inferior zonular deficiency.

Flexible nylon iris retractors are a useful adjunct to cataract surgery in cases of small pupil and subluxated lenses. A modification is presented of the standard application of iris hooks to retract the superior iris and support the inferior capsule during phacoemulsification in cases of iris coloboma with inferior zonular deficiency. Three iris hooks are applied to retract the iris, and 2 iris hooks are applied to the inferior capsule margin to support the crystalline lens in that quadrant. Clear corneal temporal phacoemulsification is then performed with adequate pupillary diameter and capsular support.

Coloboma↗
PubMed1986

[YAG laser iris hole at 6 o'clock in the periphery in the treatment or prevention of closed angle glaucoma and plateau iris and in pupillary block (posterior iris surface-blocking mechanism)].

A shunt between the anterior and the posterior chamber, achieved by shooting an iris hole with a YAG Laser, is presumed to prevent angle closure in eyes with narrow angle glaucoma. Because of their thickening effect on all types of eye tissue, it is advisable to reduce pilocarpine and other miotics once the peripheral iris hole has been created. This is best made at 6 o'clock, since any hemorrhaging caused beneath this point will cease of its own accord. The shunt brings about deepening of the peripheral chamber, and almost always widens the angle in narrow angle glaucoma.

Aged↗
PubMed2001

Prosthetic iris implantation for congenital, traumatic, or functional iris deficiencies.

PURPOSE: To determine the efficacy and safety of surgical implantation of prosthetic iris devices in patients with anatomic or functional iris deficiencies. SETTING: Cincinnati Eye Institute, Cincinnati, Ohio, USA. METHODS: Twenty-five patients were enrolled in an interventional prospective noncomparative case series. Twenty-eight eyes had prosthetic iris diaphragm implantation for traumatic iris defects, congenital aniridia or iris coloboma, herpetic iris atrophy, surgical iris loss, or ocular albinism. Prosthetic iris implantation was performed with phacoemulsification and intraocular lens (IOL) implantation in 20 eyes, secondary IOL implantation in 6 eyes, and IOL exchange in 1 eye. A single pseudophakic eye with disabling glare secondary to traumatic aniridia had secondary prosthetic iris implantation alone. The surgical ease of insertion, intraoperative and postoperative complications, postoperative anatomic results, visual acuity, and subjective glare reduction were evaluated. RESULTS: Patients were followed postoperatively for a mean of 10.2 months (range 1.4 to 25.7 months). All eyes achieved the desired anatomic result. Visual acuity was improved in 22 of 28 eyes (79%), unchanged in 5 eyes, and worsened by a single line in 1 eye. Patients were surveyed postoperatively to determine the change in glare disability. The severity of glare disability was subjectively improved in 23 of 24 patients (96%) who responded to the survey. Intraoperative complications included 3 fractured implants as well as an incomplete or torn capsulorhexis in 3 eyes. Postoperative complications included transient hypotony in 2 eyes, mild persistent inflammation in 1 eye, and macular edema followed by a retinal detachment in 1 eye with recent severe trauma. CONCLUSIONS: Implantation of prosthetic iris devices improved postoperative outcomes by reducing glare disability and, in selected cases, by correcting aphakia. Although operating on traumatized, congenitally aniridic, or uveitic eyes presents special challenges, implantation of prosthetic iris devices appears to be a safe and effective method for reducing the ubiquitous glare in patients with iris deficiency.

Adult↗
PubMed1999

[Iris vessel involvement in iris-nevus syndrome].

PURPOSE: To report a case of iris-nevus syndrome accompanied by disruption of the blood-aqueous barrier in the iris which was confirmed angiographically and histopathologically. CASE: The patient was a 39-year-old woman. She noticed blurred vision in the left eye which was diagnosed as left glaucoma. Specular microscopy revealed low endothelial cell density in the left cornea. The left iris showed atrophy with clusters of nodular iris nevus and distorted pupil. The left iridocorneal angle was closed with peripheral anterior synechia. FINDINGS: Indocyanine green iris angiography revealed more vessels on the surface of the left iris than on the right. In fluorescein iris angiography, the dye leaked from the iris vessels in areas where the iris showed advanced atrophy. The trabecular tissue obtained by trabeculectomy from the patient's left eye showed histopathologically a lining of corneal endothelial cells on the surface of the iris. The density of the vessels was high in the iris stroma. Some cells covering the vessel wall showed degeneration with opening of the zonula occludens. Schlemm's canal had narrowed lumina, and the intertrabecular spaces were closed. CONCLUSION: Disruption of the blood-aqueous barrier may occur in iris-nevus syndrome.

Adult↗
PubMed1998

US EPA's IRIS pilot program: establishing IRIS as a centralized, peer-reviewed data base with agency consensus. Integrated Risk Information System.

The US EPA's Integrated Risk Information System (IRIS) contains Agency consensus scientific positions and quantitative values on cancer and noncancer health effects that may result from lifetime oral or inhalation exposure to specific chemical substances in the environment. Combined with specific exposure assessment information, the summary health information in IRIS may be used as a source in evaluating potential public health risks from environmental contaminants. IRIS is available to the public via EPA's Internet server at http://www.epa.gov/iris. Originally developed for internal EPA use, IRIS usage has broadened since being made publicly available in 1988 to include the private and public sectors nationally and internationally. Up to 1995, IRIS summaries were generated from within various EPA Offices and Regions and reviewed by Agency Workgroups, one for cancer and one for noncancer endpoints, before entry onto IRIS. In response to the increasing usage and recognition of IRIS and suggestions for improvement, an IRIS Pilot program was initiated in 1995. The purpose of the Pilot was 3-fold: To improve efficiency in getting information on to IRIS; to improve documentation for the positions reported in IRIS summaries, including applying new methodologies and guidance; and to improve opportunity for public input including external peer review. A new infrastructure was put in place, consisting of a cross-Agency team of 'Chemical Managers', a Pilot Program Manager, and a set of Agency 'Consensus Reviewers'. Cancer and noncancer assessments were prepared in an integrated fashion for Pilot chemical substances, documented in 'Toxicological Reviews' and derivative IRIS summaries. Public input was emphasized via an initial data call and rigorous external peer review. A final step was Agency-wide consensus review by senior staff scientists representing EPA's Offices and Regions. EPA's experience with the Pilot is forming the basis for designing operational aspects of the long-term IRIS program.

Benchmarking↗
PubMedDate not supplied

alpha(1)-Adrenergic receptor antagonists and the iris: new mechanistic insights into floppy iris syndrome.

Understanding the role of adrenergic receptors in iris biology has gained widespread interest due to the recently described intraoperative floppy iris syndrome sometimes encountered during cataract surgery. alpha(1)AR-mediated iris dilator smooth muscle contraction occurs via alpha(1a)ARs whereas alpha(1b)ARs mediate iris arteriolar contraction. Because alpha(1)AR antagonists are first-line therapy for benign prostatic hyperplasia and lower urinary tract symptoms, more elderly patients requiring cataract surgery now receive these drugs. After reviewing intraoperative floppy iris syndrome, strengths/weaknesses of supporting data, and reviewing iris biology, a case is made that rather than being drug specific (alpha(1)AR antagonists), intraoperative floppy iris syndrome may represent the "tip of the iceberg." Relaxed iris dilator muscle resistant to adrenergic agonists should be expected with clinical drugs shown to relax the iris dilator (e.g., antagonists at alpha(1)AR, endothelin-A, angiotensin receptors, nitric oxide donors such as nitrates), and/or diseases associated with endothelial dysregulation (e.g., congestive heart failure, diabetes, hypertension). Rather than a rare, unexpected, unpredictable syndrome due to one drug, a careful medical history should elucidate intraoperative floppy iris syndrome predisposition. Just as anticoagulants are discontinued prior to elective surgery, conservative management of elderly patients suggests discontinuation of drugs that relax iris dilator muscle, in consultation with the patient's primary physician, should be considered prior to cataract surgery.

Adrenergic Antagonists↗
PubMedDate not supplied

Iris fluorescein angiography and iris indocyanine green videoangiography in pseudoexfoliation syndrome.

BACKGROUND: Precise evaluation of the iris vascular pattern in pseudoexfoliation syndrome (PXS) may be difficult with iris fluorescein angiography (IFA) because of the frequent presence of a heavily pigmented iris and conspicuous late leakage. However, iris indocyanine green videoangiography (IICGV) can precisely visualize details of the iris vascular pattern. This study analyzed the utility of IICGV in detecting microvascular changes in PXS and compared these findings with those of IFA. METHODS: Twenty-eight patients with PXS in both eyes underwent an ophthalmic examination including IFA and IICGV. IICGV was done with the IMAGEnet system H1024. RESULTS: IICGV gave better visualization of iris hypoperfusion and anastomotic vessels whereas iris microneovascularisation was far more clearly visible on IFA. IICGV also detected iris pigment epithelium defects. CONCLUSIONS: IICGV can be considered a useful tool for evaluation of the iris vascular pattern in PXS. Iris hypoperfusion did not appear to contribute to the development of iris microvascular changes.

Aged↗
PubMed1999

Lattice-like collagen fiber meshwork in the iris stroma of the cat: a possible mechanism to generate the tension directed towards the iris root which is required for pupillary dilatation in the sympathectomized eye.

NaOH digestion technique for collagen fiber dissection and scanning electron microscopy demonstrated a lattice-like meshwork in the anterior surface of the iris stroma of the cat. The mesh threads were made of collagen fibril bundles. In the constricted pupil, the meshes were square to rhomboid with the diagonals in the direction of the radius or circumference of the iris. In the dilated pupil, however, the meshes were strongly flattened rhomboid or ellipse with a longer diagnoal or axis in the circumferential direction. At the mesh corners facing the pupillary margin or the iris root, the collagen fibril bundles were strongly bent in the iris of the constricted pupil, while they were almost straight or slightly wavy in the iris of the dilated pupil. Accumulation of elasticity tension generated by this small distortion of the iris-mesh threads in the constricted pupil was considered to generate a tension directed towards the iris root, which is required for pupillary dilatation in the sympathectomized eye. On the posterior surface of the iris stroma, numerous thin pleats tightly woven with collagen fibrils traversed straightway through the radial length of the ciliary zone of the iris in both constricted and dilated pupils. The structural changes of these pleats in miosis and mydriasis were very small compared with the meshwork of the anterior aspect of the iris. Therefore, they were considered to work mainly as an iris skeleton.

Animals↗
PubMed2006

Endocapsular iris reconstruction implants for acquired iris defects: a clinical study.

PURPOSE: To report the clinical efficacy, safety, and long-term follow-up data on the use of endocapsular iris reconstruction implants (IRIs) during cataract surgery in patients with acquired iris defects. METHODS: Single centre, retrospective, noncomparative, interventional case series. Five eyes of four patients with acquired iris defects and visually significant cataracts underwent clear cornea phacoemulsification and intraocular lens (IOL) implantation combined with insertion of endocapsular IRI. Data on the best-corrected visual acuity (BCVA), degree of preoperative and postoperative glare, photophobia, surgical complications, and long-term implant stability were analysed. RESULTS: In all patients, IRI were successfully placed within the capsular bag during cataract surgery. There were no intraoperative or postoperative complications. Mean follow-up period was 29 months (range, 16-42). BCVA, subjective glare, and photophobia improved in all five eyes. Desired anatomic results were achieved in all of them. CONCLUSIONS: In patients with acquired iris defects, implantation of endocapsular IRI during cataract surgery appears to be a safe and effective procedure. At a mean time gate of 29 months, both IOLs and IRI appeared to remain stable within the capsular bag.

Adult↗
PubMed2004

Association between posterior uveal melanoma and iris freckles, iris naevi, and choroidal naevi.

AIM: To investigate the association between posterior uveal melanoma and iris freckles, iris naevi, and choroidal naevi. METHODS: Cross sectional study of 65 patients with posterior uveal melanoma and 218 controls. Iris colour, iris freckles, iris naevi, and choroidal naevi were recorded for each eye of each patient. RESULTS: Iris freckles were present in 40 (61.5%) patients with melanoma and 135 (61.9%) controls (p = 0.494). Iris naevi were present in four (6.2%) patients with melanoma and nine (4.1%) controls (p = 0.955). Choroidal naevi were present in 12 (18.5%) patients with melanoma and 38 (17.4%) controls (p = 0.815). CONCLUSION: This study did not detect an association between posterior uveal melanoma and iris freckles, iris naevi, or choroidal naevi.

Adult↗
PubMed1991

[Iris reconstruction: surgery, laser or contact lenses with iris structure].

We report the results of 126 iris reconstructions from 1979 to 1989 at the Rostock University Eye Clinic: 68 were operative, 34 laser treatments, and 24 Hema contact lenses with an iris structure. We developed four variations of the iridopexy: (1) an iridopexy with an iris micronhook; (2) an operation with an iris catching device; (3) the procedure using anterior chamber forceps according to Barraquer; (4) the suction cannula technique. These four variations permit damage to the epithelium to be avoided--unlike the McCannel or Makkensen techniques. Four fixation of the iris, in phakic eyes two pupil punches were patented. For aphakic eyes, we prefer to fix the iris via a combination of argon and neodym-YAG laser surgery. To date, the most important indications for fitting the Hema contact less with an iris structure have been aniridia, albinism, iris coloboma, essential iris atrophy, and leucoma corneae.

Contact Lenses↗
PubMed2000

Iris varix simulating an iris melanoma.

Iris varix is rare and little is known about its clinical characteristics. We treated a thrombosed iris varix that simulated an iris melanoma. A 53-year-old man developed a dark brown iris mass and hyphema in his left eye. Ultrasound biomicroscopy revealed a circumscribed mass of the iris stroma. Because of suspicion for melanoma, it was removed by sector iridectomy. Histopathologic examination disclosed an extensive focus of stromal hemorrhage, partially surrounded by endothelial cells that showed immunoreactivity to vascular markers. The histopathologic diagnosis was thrombosed iris varix. Iris varix is a rare condition that should be included in the differential diagnosis of iris melanoma.

Diagnosis, Differential↗
PubMed1978

Fluorescein iris angiography. II. Disturbances in iris circulation following strabismus operation on the various recti.

Iris circulation was investigated by fluorescein iris angiography in 33 human eyes before and after tenotomy of one or more recti for correction of strabismus. Tenotomy of one or both horizontal recti produced no appreciable circulatory disturbance in the iris, but tenotomy of superior or inferior rectus produced circulatory delay in superior temporal or inferior temporal sectors, respectively, of the iris. When tenotomies of a horizontal and one or two vertical recti were combined, the defect occurred in the region of the vertical rectus only. Blood supply of the nasal half of the iris was usually not disturbed by tenotomy of the vertical and/or medial rectus. The findings indicate that the blood supply of the iris is segmental and suggest that, in strabismus surgery, cutting the two vertical recti along with the lateral rectus may subject the eye to the risk of anterior segment ischemia. In the light of the present findings, physiological anatomy of the blood supply of the iris and role of the major arterial circle of the iris are discussed.

Adolescent↗
PubMed1999

Indocyanine green iris angiography of lung carcinoma metastatic to the iris.

BACKGROUND: To investigate the usefulness of indocyanine green (ICG) iris angiography for monitoring vascular abnormalities and the clinical course of metastatic iris tumor during chemotherapy. METHODS: We performed ICG iris angiography at several points during systemic chemotherapy for a 67-year-old man who had been diagnosed as having small-cell carcinoma of the lung with metastatic iris tumors. RESULTS: ICG iris angiography clearly demonstrated hyperfluorescent tumor vessels, rubeosis iridis, and dilated iris stromal vessels. After chemotherapy, these hyperfluorescent vessels and rubeosis regressed. CONCLUSION: ICG iris angiography appears to be an effective and useful method for observing abnormal vessels associated with metastatic iris tumors.

Aged↗
PubMed1998

Lamellar intrastromal corneal tattoo for treating iris defects (artificial iris)

PURPOSE: Defects in the iris are associated with clinically significant optical anomalies, such as glare and peripheral light scatter; however, current artificial-iris technology remains inadequate. The purpose of this study was to explore the practicality of a lamellar intrastromal tattoo technique as a treatment modality to correct optical and cosmetic defects resulting from simulated iris abnormalities in eye-bank eyes. METHODS: Simulated iris defects (abnormally large pupil, sector iridectomy, iridodialysis, and aniridia) were produced in a series of eye-bank eyes. Depending on the simulated iris defect, one or two lamellar channel(s) were created at 50% depth of the cornea via a peripheral incision (1.8 mm) with specialized proprietary instruments (KeraVision, Inc., Fremont, CA, U.S.A.). Commercially available tattoo pigment was inserted through the lamellar channel(s) and blended into the defective region of the iris. RESULTS: The tattoo treatment was relatively simple to perform. Tattoo pigment was inserted uniformly through the small incision, and adequate color blending to match the recipient iris was achieved. The intrastromal tattoo effectively obscured light. CONCLUSION: The lamellar intrastromal tattoo technique appeared to be efficacious for treating different types of iris defects in eye-bank eyes. Further investigation of this technique in nonsighted patient eyes is warranted.

Corneal Stroma↗
PubMed1999

New iris retractor for pupil dilatation during anterior vitrectomy: double-hook iris retractor.

To report a new iris retractor as a tool for pupillary dilatation in eyes with a small pupil. This instrument was designed to prevent the retractor from dropping out of corneal incision, especially during anterior peripheral vitrectomy requiring a scleral indentation. A new iris retractor was designed with the top in the form of a double-hook, based on the conventional flexible iris retractor. The new instrument was used in 16 eyes, and the conventional flexible iris retractor was used in 14 eyes, with proliferative retinopathy or proliferative diabetic retinopathy in cases in which anterior vitrectomy was performed. The number of times that the instrument has been replaced were recorded. The conventional flexible iris retractor was replaced at mean number of 4.2 times, while the new iris retractor was replaced a mean number of 0.3 times during vitreous surgery. The difference was statistically significant (P = 0.009, Mann-Whitney test). The new iris retractor can easily hook onto the iris and is useful in anterior vitrectomy.

Eye Diseases↗
PubMed2005

Surgical management of iris defects with prosthetic iris devices.

PURPOSE: To evaluate the safety and efficacy of surgical implantation of prosthetic iris devices in patients with iris deficiency. METHODS: Nine patients with traumatic iris defects, congenital aniridia or iris coloboma, and surgical or optical iridectomies were included in a noncomparative case series. Cataract surgery with intraocular lens and prosthetic iris implantation was performed in 10 eyes. The visual acuity, subjective degree of glare disability, postoperative anatomic results, and intraoperative and postoperative complications were evaluated. RESULTS: The mean follow-up was 17.75 months (range 4-48 months). Best-corrected visual acuity improved in nine of 10 eyes (90%) and remained unchanged in one eye. Glare subjectively improved in four of five eyes (80%) of patients complaining of glare preoperatively. All eyes achieved the desired anatomic result. Intraoperative complications included one anterior capsular tear. Postoperative complications included a short period of mild postoperative anterior uveitis in four eyes. Secondary glaucoma was absent. CONCLUSION: In patients with iris deficiency, implantation of prosthetic iris device, and intraocular lens implant following cataract surgery appears to be safe and effective in reducing glare disability and improving visual outcomes.

Adult↗