Pigmented Trabecular Meshwork Research Articles

Die Vorhersagefaktoren einer erfolgreichen selektiven Lasertrabekuloplastik bei Offenwinkelglaukom

The aim of this study was to determine factors that predict successful selective laser trabeculoplasty (SLT) in open-angle glaucoma (OAG). In 122 eyes suffering from OAG, treatment was carried out with a frequency-doubled, Q-switched Nd:YAG laser (532 nm). The intraocular pressure (IOP) was measured before the treatment and 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78 and 84 months thereafter. Success was defined as an IOP reduction exceeding 20 % of the pretreatment IOP. Correlations between successful SLT and baseline IOP, age, sex, hypertension, diabetes mellitus, family history of glaucoma, previous anterior segment surgery, the grade of trabecular meshwork pigmentation, laser energy used, and local antiglaucoma therapy were determined. The mean follow-up time was 43.4 months (SD: 25.6). The mean pretreatment IOP was 22.5 mmHg (SD: 2.8). The success rate after 12 months determined from the Kaplan-Meier survival analysis was 88 %, after 24 months 79 %, after 36 months 67 %, after 48 months 58 %, after 60 months 49 % and after 84 months 48 %. We found statistically significant negative correlation betweens successful SLT and the grade of trabecular meshwork pigmentation (r = -0.234; p = 0.01), diabetes mellitus (r = -0.223; p = 0.014). We found no statistically significant correlations between successful SLT and baseline IOP, age, sex, hypertension, family history of glaucoma, previous anterior segment surgery, laser energy used, local antiglaucoma therapy. SLT success in OAG with a mean follow-up time of 43.4 months was significantly predicted by the lower grade of trabecular meshwork pigmentation and the absence of diabetes mellitus.

Annular and central heavy pigment deposition on the posterior lens capsule in the Pigment dispersion syndrome

To report annular and central heavy pigment deposition on the posterior lens capsule in a case of pigment dispersion syndrome. Case report. A 36-year-old female with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the right eye over the past 1-2 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including bilateral Krunkenberg spindles, iris transillumination defects, and dense trabecular meshwork pigmentation. Remarkably, annular and central dense pigmentation of the posterior lens capsule was noted in the right eye. Annular pigment deposition on the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The way of central pigmentation is the entrance of aqueous to Berger's space. In our case, it is probable that spontaneous detachment of the anterior hyaloid membrane aided this entrance.

Pigmentary dispersion syndrome with a secondary piggyback 3-piece hydrophobic acrylic lens: Case report with clinicopathological correlation

We describe a case of pigmentary dispersion syndrome resulting from secondary piggyback implantation of a 3-piece hydrophobic acrylic squared-edged intraocular lens (IOL) in the ciliary sulcus. The intraocular pressure remained elevated despite pharmacological treatment, with a heavily pigmented trabecular meshwork. The piggyback IOL was subsequently explanted and replaced by a silicone IOL with smooth round edges. Examination of the explanted IOL under light and scanning electron microscopy showed clusters of pigment epithelial cells located around the periphery of the anterior optic surface.

Augendrucksenkung nach selektiver Lasertrabekuloplastik (SLT) mit zwei unterschiedlichen Lasersystemen und nach Argonlasertrabekuloplastik (ALT) - Eine kontrollierte prospektive klinische Studie an 284 Augen

Selective laser trabeculoplasty (SLT) is a new method to reduce intraocular pressure in eyes with primary open angle glaucoma. The laser parameters of a Q-switched, frequency-doubled Nd:YAG-laser are set to selectively target pigmented trabecular meshwork cells without visible damage to the adjacent non-pigmented tissue. SLT acts non-thermally, the intracellular microdisruptions triggered by the laser are confined to the targeted cells, the laser pulses are so short that heat caused within the targeted cells does not have time to spread to the surrounding tissue. A controlled prospective randomised clinical study was conducted to compare the long-term results, safety and efficacy after SLT with two different laser systems and after ALT in the treatment of ocular hypertension and medically uncontrolled open angle glaucoma. About two years ago the authors performed a selective laser trabeculoplasty in 119 eyes using the SLT laser unit Otello (Glautec AG, ARC, EC), here named as SLT-I, and in 124 eyes using the SLT laser unit Selecta II (Lumenis, Palo Alto, CA), here named as SLT-II. In 41 eyes the authors performed argon laser trabeculoplasties using the argon laser Argus (Aesculap Meditec, EC). Two months after treatment mean IOP reduction from baseline was 1.9 mmHg or, respectively, 8.8 % after SLT with the SLT-System I, 2.0 mmHg or, respectively, 9.5 % after SLT with SLT-System II, and 2.2 mmHg or, respectively, 9.9 % after ALT with the argon laser. Twelve months after LTP mean pressure reductions were 1.7 mmHg (7.9 %) after SLT-I, 1.8 mmHg (8.5 %) after SLT-II, and 2.1 mmHg (9.4 %) after ALT. The response curve of the eyes with SLT-I greatly resembled that of the eyes with SLT-II and those eyes with ALT. Pressure reduction was highest after ALT, followed by SLT-II, in SLT-I reduction was the least, but the differences were not significant. Our findings did not correspond with those of other authors reporting an average IOP reduction of 25 % after SLT and ALT. SLT has shown reasonable efficacy in lowering IOP in eyes with ocular hypertension and primary open angle glaucoma, SLT achieves about the same level of IOP reduction compared with ALT. As a result of the preservation of the structure of the trabecular meshwork and low rate of complications, SLT is a safe alternative to ALT. The exact biological effect induced with SLT is still not yet understood. For the early glaucoma stages SLT provides an alternative to drug treatment, for the advanced glaucomas SLT is an additional option for further pressure reduction. More long-term follow-up studies are needed to determine whether the IOP lowering effect is sustained over time, and to assess the efficacy of repeated SLT.

Studies of Optineurin, a Glaucoma Gene: Golgi Fragmentation and Cell Death from Overexpression of Wild-Type and Mutant Optineurin in Two Ocular Cell Types

Optineurin (OPTN) has recently been linked to glaucoma, a major cause of blindness worldwide. Mutations in OPTN such as Glu50-->Lys (E50K) have been reported in patients, particularly those with normal pressure glaucoma. Here, we show that the endogenous OPTN was not secreted in two ocular cell types, human trabecular meshwork and retinal pigment epithelial cells. It localized instead in the cytoplasm in a diffuse pattern without a distinct association with the Golgi apparatus. When overexpressed, however, wild-type OPTN-green fluorescent protein (GFP) formed foci especially around the Golgi, colocalizing partially with the common endocytic pathway marker transferrin receptor in both cell types. Fragmentation of the Golgi was also observed. On nocodazole treatment, the OPTN foci were dispersed into the cytoplasm. Overexpression of mutant OPTNE50K-GFP resulted in a greater number (P<0.0055) and size of the foci, compared with the wild type, and the Golgi alteration was potentiated. Cell loss observed in OPTN-expressing cultures was also more pronounced in OPTNE50K-GFP compared with that of wild-type OPTN-GFP counterparts (P<0.01). This study highlights a possible role of OPTN in vesicle trafficking and Golgi integrity. It also provides in-sights into the possible mechanisms why E50K would exhibit a propensity toward the development of glaucoma.

Elevated intraocular pressure in secondary piggyback intraocular lens implantation

We report 2 cases of postoperative intraocular pressure (IOP) elevation in secondary piggyback intraocular lens (IOL) implantation without history of glaucoma or ocular hypertension. A 74-year-old woman with myopic pseudophakia and a 68-year-old man with hyperopic pseudophakia received secondary piggyback AcrySof IOL implantation in their left eyes. In both patients, the left IOP gradually increased and sustained around 30 mm Hg for about 1 year. In the first, IOP continued elevating despite topical and systemic medications. There was an episode of pupillary block in the second. Gonioscopically, heavier trabecular meshwork pigmentation in their left eyes was observed. Because of this, the 2 IOLs implanted were removed and replaced by an adequate IOL and trabeculotomy was performed in the former. The AcrySof IOL has a truncated optic edge, which increases the risk for chafing the iris, resulting in pigment dispersion syndrome; thus, it would be a poor choice for a sulcus-placed piggyback implantation.

Selective Laser Trabeculoplasty (SLT) Complicated by Intraocular Pressure Elevation in Eyes With Heavily Pigmented Trabecular Meshworks

To report and assess the complication of intraocular pressure (IOP) elevations after selective laser trabeculoplasty (SLT) in patients with heavily pigmented trabecular meshworks. Noncomparative, observational case series. Retrospective analysis of the medical files of four glaucoma patients with heavily pigmented trabecular meshwork, who presented with IOP elevations after SLT. All four glaucoma patients presented with post-SLT IOP elevations. Three had features of pigmentary dispersion syndrome, and the fourth had a heavily pigmented trabecular meshwork. Two patients had previous argon laser trabeculoplasty (ALT) in the same eye in which SLT was performed, and one had a previous ocular trauma. Eventually, three of the patients required surgical trabeculectomy. This case series suggests that post-SLT IOP elevations can be a serious adverse event in some glaucomatous patients. It is recommended by the authors that patients with a deeply pigmented trabecular meshwork, taking multiple topical medications and having previous ALT treatment, should be considered at higher risk for this complication.

Langzeitergebnisse nach selektiver Lasertrabekuloplastik - eine klinische Studie an 269 Augen

Selective laser trabeculoplasty SLT is a new method to reduce intraocular pressure in eyes with primary open angle glaucoma. With a Q-switched, frequency-doubled Nd:YAG laser it targets the pigmented trabecular meshwork cells without visible damage to the adjacent non-pigmented tissue. SLT acts non-thermally, the intracellular microdisruptions triggered by the laser are confined to the targeted cells, the laser pulses are so short that heat created within the targeted cells does not have time to spread to the surrounding tissue. A clinical prospective study was conducted to evaluate the long-term results, safety and efficacy of SLT in the treatment of open angle glaucoma. Since 2002, we have performed a selective laser trabeculoplasty in 269 eyes: in 17 eyes with ocular hypertension, in 239 eyes with primary open angle glaucoma, in 11 eyes with low tension glaucoma, while 2 eyes had a secondary glaucoma due to uveitis. In 22 eyes the primary initial treatment was SLT. Three months after treatment, the mean IOP reduction from baseline was 3.4 mm Hg, respectively 15 %, after 12 months the mean IOP reduction was 3.0 mm Hg (12.9 %), and after 24 months 2.7 mm Hg or 12.1 %. The response curve of the eyes with ocular hypertension greatly resembled the eyes with primary open angle glaucoma and with low tension glaucoma. SLT has shown reasonable efficacy in lowering IOP in eyes with primary open angle glaucoma and ocular hypertension, both as a first-line treatment and as a treatment in medication-refractory eyes. SLT is effective for patients who have had prior treatment with ALT. Long-term follow-up studies are needed to determine whether the IOP lowering effect is sustained over time, and to assess the efficacy of repeated SLT. The exact biological effect induced with the SLT is still not understood.

Goniosurgery for Glaucoma Secondary to Chronic Anterior Uveitis

To describe the preoperative prognostic factors that correlate with the surgical success of goniosurgery for glaucoma complicating chronic anterior uveitis and to describe the surgical technique. The medical records of 31 patients with 31 eyes with glaucoma secondary to chronic anterior uveitis for which 38 goniotomy procedures were performed were reviewed. Uveitis etiology, gender, age of onset of iritis, duration of iritis before recognition of glaucoma, duration of iritis and duration of glaucoma until initial goniosurgery, preoperative gonioscopic findings, lens status, surgical outcome, age at initial goniosurgery, duration of postoperative observation, lens status, preoperative and postoperative intraocular pressures, topical steroid, and glaucoma medication use were reviewed. Complete success was defined by an intraocular pressure (IOP) < or = 21 mm Hg, and qualified success as IOP < or = 21 mm Hg with use of glaucoma medications. The surgical technique used to perform the goniosurgery was reviewed. Overall surgical success was achieved in 22 (71%) of 31 eyes. The mean age at surgery was 10.2 +/- 4.2 years (range, 4-21 years). All but 8 patients were female. Mean follow-up interval was 10.3 +/- 6.4 years (range, 1.5-22 years). Significant correlation was found between outcome and age at initial surgery, lens status, duration of glaucoma before goniosurgery, duration of iritis before glaucoma surgery, and hours of peripheral anterior synechia (PAS). The mean number of clock hours of preoperative (PAS) was 0.5 hours in eyes with success versus 2.5 hours in eyes with failure. Age of onset of iritis, duration of iritis before recognition of glaucoma, trabecular meshwork pigmentation (TM), TM opacification, and circumferential ciliary body band narrowing did not correlate with surgical outcome. Goniosurgery is an effective treatment of glaucoma secondary to chronic anterior uveitis. The outcome of surgery was unfavorably influenced by older age, longer duration of glaucoma, and evidence of more advanced preoperative filtration angle abnormalities secondary to uveitis. Goniosurgery for this secondary glaucoma can be successfully performed utilizing the standard goniotomy technique.

One-Year Follow-Up of Selective Laser Trabeculoplasty in Open-Angle Glaucoma

Background: Selective laser trabeculoplasty (SLT) targets the pigmented trabecular meshwork (TM) cells without damage to the adjacent non-pigmented tissue. A study was conducted to evaluate the efficacy and safety of SLT in the treatment of uncontrolled open-angle glaucoma. Methods: In a prospective non-randomized study 44 eyes of 31 patients with uncontrolled open-angle glaucoma were treated with a frequency-doubled, Q-switched Nd:YAG laser. A total of approximately 50 spots were placed over 180° of the TM at energy levels ranging from 0.7 to 0.9 mJ. Intraocular pressure (IOP) was measured 1, 2, and 24 h, 1 and 2 weeks and 1, 2, 3, 6, 9, and 12 months after treatment. Results: The average pre-operative IOP was 25.6 (SD 2.6) mm Hg (range 22–34). The mean IOP reduction from baseline at 24 h, 3, 6 and 12 months was 7.1 mm Hg (SD 3.5) or 27.6%; 4.2 mm Hg (SD 3.5) or 16.4%; 4.7 mm Hg (SD 4.2) or 18.6%, and 4.4 mm Hg (SD 3.8) or 17.1%, respectively. The percent of eyes with IOP reduction of 3 mm Hg or more at 3, 6 and 12 months was 66, 78 and 62%. A pressure spike of 8 mm Hg or more was detected in 4 eyes (9.1%). Anterior chamber reaction was seen 1 h after SLT and was mild to moderate in 16 eyes (40.4%) and marked in 3 eyes (6.8%). Conclusions: SLT has shown reasonable efficacy in lowering IOP over 1-year follow-up, but there was a tendency for IOP to increase with a longer follow-up. Long-term follow-up studies with a large sample size are needed to determine whether the IOP lowering effect is sustained over time, and to assess the efficacy of repeated SLT.

Long anterior zonules and pigment dispersion

Purpose To describe pigment dispersion associated with long anterior zonules. Design Multicenter observational case series. Methods Fifteen patients, seven of whom were treated for glaucoma or ocular hypertension, were identified with long anterior zonules and pigment dispersion. Transmission electron microscopy was performed on one anterior capsule specimen. Results All patients had anterior zonules that inserted centrally on the lens capsule. Signs of pigment dispersion included corneal endothelial pigmentation, loss of the pupillary ruff, and variable trabecular meshwork pigmentation. Ultrasound biomicroscopy verified the lack of posterior iris insertion and concavity. There was no exfoliation material. Transmission electron microscopy showed zonular lamellae with adherent pigment granules, and no exfoliation material. Conclusions Long anterior zonules inserted onto the central lens capsule may cause mechanical disruption of the pigment epithelium at the pupillary ruff and central iris leading to pigment dispersion.

What is the risk of developing pigmentary glaucoma from pigment dispersion syndrome?

Purpose To determine the probability of converting from pigment dispersion syndrome to pigmentary glaucoma. Design Retrospective community-based study of all newly diagnosed cases of pigment dispersion syndrome or pigmentary glaucoma. Methods Subjects were patients newly diagnosed with pigment dispersion syndrome or pigmentary glaucoma from 1976 to 1999 in Olmsted County, Minnesota. Criteria for pigment dispersion syndrome were two of three signs: midperipheral, radial iris transillumination defects; Krukenberg spindle; heavy trabecular meshwork pigmentation. Criteria for pigmentary glaucoma were pigment dispersion syndrome and two of three findings: intraocular pressure (IOP) greater than 21 mm, optic nerve damage, or visual field loss. Kaplan-Meier survival curves were used to determine the probability of conversion to pigmentary glaucoma. Results A total of 113 patients were newly diagnosed with pigment dispersion syndrome over the 24-year period. Of these, 9 persons developed pigmentary glaucoma or elevated IOP requiring therapy. The probability of converting to pigmentary glaucoma was 10% at 5 years and 15% at 15 years. An additional 23 patients were found to have pigmentary glaucoma at their initial examination. The mean age at diagnosis of pigmentary glaucoma was 42 ± 12 years; 78% of patients were male, whereas 58% of patients with pigmentary dispersion syndrome glaucoma were male. The most significant risk factor for conversion to pigmentary glaucoma was an IOP greater than 21 mm Hg at initial examination, whereas age, refractive error, and family history of glaucoma were not correlated with conversion. Conclusion The risk of developing pigmentary glaucoma from pigment dispersion syndrome was 10% at 5 years and 15% at 15 years. Young, myopic men were most likely to have pigmentary glaucoma. An IOP greater than 21 mm Hg at initial examination was associated with an increased risk of conversion.

"Masked" pseudoexfoliation syndrome in unoperated eyes with circular posterior synechiae: clinical-electron microscopic correlation.

To investigate the prevalence of "masked" pseudoexfoliation (PEX) syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. Cross-sectional prospective study. Twenty-eight eyes of 27 consecutive patients with circular posterior synechiae and a history of miotic drug use without previous intraocular surgery, inflammation, or trauma, and without conventional signs of PEX material in the anterior chamber were included in the study. All eyes were investigated by slitlamp biomicroscopy and gonioscopy of the anterior chamber before extracapsular cataract surgery for the presence of typical PEX-associated iris pigment epithelial changes, such as peripupillary atrophy and trabecular meshwork melanin granule deposition. The anterior chamber depth, lens thickness, and axial lengths of the eyes were measured by A-scan immersion sonography. The excised anterior lens capsules obtained during extracapsular cataract surgery were investigated for the presence of precapsular fibrillar PEX deposits by electron microscopy. The prevalence of masked PEX syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. Transmission electron microscopy of unselected nonserial sections revealed a precapsular layer consisting of typical PEX fibers or microfibrils, which indicated early stages of PEX syndrome in 18 (64%) of 28 eyes with circular posterior synechiae. Melanin granules were frequently found adhering to the fibrillar layer. Eyes with precapsular fibrillar deposits showed significantly greater trabecular meshwork pigmentation than eyes without such deposits. Differences in age, lens thickness, axial length of the eye, anterior chamber depth, and degree of peripupillary atrophy were, however, not statistically significant between the groups with and without electron microscopic evidence of PEX deposits. Circular posterior synechiae were more frequently associated with manifest or early stages of PEX syndrome. However, the formation of broad posterior synechiae in miosis prevented a definite clinical diagnosis based on the classic changes of the anterior lens capsule. In eyes with spontaneous or miotic-induced circular posterior synechiae without other obvious cause, the masked variant of PEX syndrome should always be considered.

Unilateral or asymmetric pseudoexfoliation syndrome? An ultrastructural study.

Clinically, most patients with pseudoexfoliation (PEX) syndrome reveal only unilateral ocular involvement. However, the generalized nature of the disorder suggests that PEX syndrome is clinically asymmetric rather than strictly unilateral. To perform an ultrastructural study of the contralateral eyes in patients with unilateral PEX syndrome. Five pairs of donor eyes with slitlamp microscopic, macroscopic, and light microscopic evidence of unilateral PEX syndrome and 6 normal control eyes were investigated by transmission electron microscopy and light and electron microscopic immunohistochemistry using antibodies against the human natural killer (HNK-1) epitope and against latent transforming growth factor beta1-binding protein, both markers for the identification of PEX deposits. Ultrastructural alterations were observed in anterior segment tissues of all apparently not involved fellow eyes. These included (1) deposits of typical PEX fibrils on the iris and ciliary epithelia and in the dilator muscle of the iris; (2) increased accumulation of extracellular matrix, including microfibrils and reduplicated basement membrane material in the periphery of iris vessels, in the dilator muscle and in the juxtacanalicular tissue of the trabecular meshwork; and (3) degenerative changes of the iris pigment epithelium and dilator muscle cells. Latent transforming growth factor beta1-binding protein- and HNK-1-positive deposits indicating PEX material accumulations were detected in the periphery of iris vessels and in the dilator muscle in all affected and contralateral eyes, but not in the control eyes. These subclinical alterations of contralateral eyes in clinically so-called unilateral PEX syndrome support the concept that PEX syndrome is a generalized basically bilateral disorder with a clinically marked asymmetric manifestation. The iris changes may account for the clinical signs characteristic of early stages, such as melanin dispersion, peripupillary atrophy, trabecular meshwork pigmentation, and insufficient asymmetric mydriasis. The findings should be considered in the clinical management of the patients. In view of the fact that PEX syndrome is the most common identifiable cause of open-angle glaucoma worldwide and as it is an important risk factor for a wide spectrum of ocular complications, particularly during cataract surgery, the potential involvement of both eyes in the PEX process is of clinical significance.

Anterior Chamber Angle Anomalies Associated with Signs of Pigment Dispersion in a Group of Black Probands and Their First-Degree Relatives

To evaluate the presence of iridocorneal angle anomalies associated with signs of pigment dispersion among a group of black probands and their first-degree relatives. Eleven blacks who exhibited pigment dispersion syndrome (PDS) signs, including Krukenberg's spindles, moderate-to-heavy trabecular meshwork pigmentation, and peripheral lenticular/zonular pigmentation, received a complete eye examination that included gonioscopy. Overt iridocorneal angle abnormalities other than pigment deposition were photo-documented. Twenty-two first-degree relatives (6 siblings, 15 children, and 1 parent) of these probands underwent similar examination. Among the subjects, 5 of 11 probands (age range 13 to 59 years) and 4 of 22 relatives (age range 14 to 51 years) exhibited definite angle anomalies. The nine subjects with angle anomalies belonged to 7 of 11 separate families. The four relatives with angle anomalies did not have PDS according to our criteria, but two other relatives from two additional families did have signs consistent with clinical PDS. Types of angle anomalies included (1) peripheral anterior synechia-like lesions; (2) a prominent concavity of the peripheral iris at the 6-o'clock meridian; (3) a whitish, thread-like band of tissue near the iris base; (4) a prominent, externally-visible Schwalbe's line at the 6-o'clock meridian; and (5) a prominent, web-like confluence of exaggerated iris processes 360 degrees along the angle wall. Iris processes and prominent Schwalbe's lines were not considered abnormal or anomalous unless they were clearly atypical. Iridocorneal angle anomalies, other than pigment deposition, were common among our black group who exhibited signs of pigment dispersion as well as among their first-degree relatives. Further consideration should be given to the possibility that among some patient groups, overt goniodysgenesis could be part of a constellation of signs indicative of a pigment dispersion syndrome. Potentially, clinically detectable goniodysgenesis could prove to be a useful marker to identify certain subjects who carry PDS genetic traits but who have not expressed complete phenotypical disease.

Familial occurrence of pigment dispersion syndrome

Background: Pigment dispersion syndrome affects up to 4% of the white population. It is characterized by the presence of transillumination defects, Krukenberg's spindle and dense trabecular meshwork pigmentation. Open-angle glaucoma will develop in as many as 50% of affected patients. In this study we describe the familial occurrence of pigment dispersion syndrome in six North American pedigrees and the phenotypic characteristics with respect to pigment dispersion syndrome and glaucoma.Methods: Probands with pigment dispersion syndrome were identified in glaucoma clinics at university eye centres in Ottawa and Durham, NC. Families with two or more affected members were evaluated. All willing members in each family underwent a thorough clinical examination and were classified as affected with pigment dispersion syndrome, suspect or unaffected. The previous medical records were reviewed to obtain the past medical and ocular history, including risk factors for glaucoma.Results: All six families are white. Three families show at least two generations of affected members. Of the 43 subjects examined 58% were women. All 14 affected members showed moderate to heavy trabecular meshwork pigmentation and either Krukenberg's spindle or transillumination defects. The affected members were also considerably more myopic (mean spherical equivalent for the right eye -4.72 dioptres) than the suspect group or the unaffected group (mean spherical equivalent -0.79 D and + I . 19 D respectively) (p ≤ 0.001), and the intraocular pressure was higher for the affected than the unaffected group (mean for the right eye 20 mm Hg vs. 16 mm Hg) (p = 0.004). Half of those affected also had open-angle glaucoma.Interpretation: We have identified and phenotypically characterized six North American families with autosomal dominant pigment dispersion syndrome. Our ultimate goal is to identify the gene(s) that causes this disorder in order to clarify its molecular etiology and pathophysiology. This may give rise to a molecular classification of the disease as well as provide the foundation for genetic testing and new treatment approaches.

Pigmented striae of the anterior lens capsule and age-associated pigment dispersion of variable degree in a group of older African-Americans: an age, race, and gender matched study.

To investigate pigmented striae of the anterior lens capsule in African-Americans, a potential indicator of significant anterior segment pigment dispersion. A group of 40 African-American subjects who exhibited pigmented lens striae (PLS) were identified from a non-referred, primary eye care population in Chicago, IL, USA. These subjects were then compared to an age, race, and gender matched control group relative to refractive error and the presence or absence of diabetes and hypertension. The PLS subjects (mean age = 65.4 +/- 8.8 years, range = 50-87 years) consisted of 36 females and 4 males. PLS were bilateral in 36 (85%) of the 40 subjects. Among the eyes with PLS, 21 (55%) of 38 right eyes and 22 (61%) of 36 left eyes also had significant corneal endothelial pigment dusting, commonly in the shape of a Krukenberg's spindle. Ten (25%) of the PLS subjects had either glaucoma or ocular hypertension (7 bilateral, 3 unilateral). The presence of trabecular meshwork pigment varied from minimal to heavy. The mean +/- SD (range) refractive error of the PLS right eyes was +1.61 +/- 1.43D (-1.50 to +5.00D) and +1.77 +/- 1.37D (-1.00 to +5.00D) for the left eyes. Based on these data, the PLS right eyes were +1.63D (Student's t, p = 0.0001; 95% CI = +0.82 to +2.44D) more hyperopic on average than the control right eyes, and the PLS left eyes were +1.77D (p = 0.0001; 95% CI = +0.92 to +2.63D) more hyperopic on average than the control left eyes. Trend analysis showed a gradually increasing likelihood of PLS with increasing magnitude of hyperopia in both eyes (Mantel-Haenszel chi-square, p = 0.001). Among PLS subjects, 24 (60%) of 40 were hypertensive and 9 (23%) of 40 were diabetic. However, these proportions were not significantly different (two-tailed Fisher's exact test; hypertension: p = 0.30; diabetes: p = 0.70) from the randomly selected controls. Among our African-American group, which consisted predominately of females >50 years of age, the likelihood of PLS increased with increasing hyperopic refractive error. This finding is consistent with the possibility that PLS may, in some circumstances, indicate a significant pigment dispersal process due to iris-lens rubbing that may be associated with crowding of anterior segment structures. Additional study is warranted to further assess the nature of PLS, their precise relationship with an age-related pigment dispersal process, and their true significance as a risk factor for development of glaucoma.

Responses of different cell lines from ocular tissues to elevated hydrostatic pressure

BACKGROUND/AIMSMechanical forces are thought to induce cellular responses through activation of signalling pathways. Cells within the intraocular environment are exposed to constant changes in the levels of intraocular pressure. In...

Clinical Results of Selective Laser Trabeculoplasty

Purpose: Selective laser trabeculoplasty (SLT) is a new laser procedure using a frequency-doubled Q-switched Nd:YAG laser (wavelength: 532 mm). The laser parameters are set to selectively target pigmented trabecular meshwork (TM) cells without coagulative damage to the TM structure or non-pigmented cells. We investigated the safety and efficacy of SLT in lowering intraocular pressure (IOP). Subjects and Methods: Sixty-seven eyes of 67 patients with uncontrolled open angle glaucoma were treated with the Coherent Selecta 7000 ® (Coherent Inc., Palo Alto, CA). Nineteen of 67 patients had previously received argon laser trabeculoplasty. A total of approximately 60 non-overlapping spots were placed over 180 degrees of the TM ranging from 0.5 to 1.0 mJ per pulse. The maximum energy level at which no bubble formation was observed determined choice. Results: The average preoperative IOP was 22.4 mm Hg. Six months after the operation, mean IOP reduction was 4.4 mm Hg, and mean outflow pressure (OP) reduction was 38.1%. One month after the operation 68.7% of patients responded to treatment with an OP reduction of at least 20% (“responders”). Transient IOP elevation of 5 mm Hg or greater was seen in 25.4% of patients. The success rate at 6 months after operation was 64.6% for all patients (67 eyes) and 78.2% for the responders (46 eyes). An analysis using a Cox proportional hazard model showed that a low preoperative IOP was the significant determinant for success, and the hazard ratio for the IOP increase of 5 mm Hg was 2.12. Other factors such as age, gender, past history of ALT, and goniopigment were not significantly related to success. Conclusion: SLT appears to be a safe and effective way to lower IOP.

Immediate intraocular pressure response to selective laser trabeculoplasty

BACKGROUND/AIMSSelective laser trabeculoplasty targets the pigmented trabecular meshwork cells without damage to the trabecular meshwork architecture in vitro. A study was conducted in vivo of eight eyes with uncontrolled open...