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At least 1,531 records · Page 85Linked to original sources
PubMed1996

Effect of intraocular lens fixation on acute intraocular pressure rise after neodymium-YAG laser capsulotomy.

Neodymium-YAG laser posterior capsulotomy is associated in some cases with an acute rise in the intraocular pressure (IOP), possibly caused by blockage of the trabecular meshwork by debris. To test the hypothesis that the IOP rise is preventable if fixation of the intraocular lens (IOL) in the capsular bag is ensured, we conducted a study comparing IOP changes at 1, 2, 3 and 24 hours after Nd:YAG capsulotomy between eyes with capsular bag-fixated, one haptic in the bag (haptic in/out) and cillary sulcus-fixated IOLs. Analysis of variance for repeated measures showed that after capsulotomy there were significant increases in IOP from baseline (p < 0.05) in both the sulcus-fixated (1, 2 and 3 hours) and haptic in/out groups (2 and 3 hours), while IOPs in the bag-fixated group did not show any significant increase. The increases in IOP in the sulcus-fixated group at 1, 2 and 3 hours after capsulotomy were significantly higher than the IOP changes at the corresponding periods in the other two groups (Kruskal-Wallis test, p < 0.01). The mean maximum IOP rise in the sulcus-fixated group (11.33 +/- 7.85 mmHg) was significantly higher than that in the haptic in/out group (3.89 +/- 7.14 mmHg) and the bag-fixated group (1.10 +/- 2.71 mmHg), while there was no difference between the latter two groups. In 57.5% of the sulcus-fixated group, 5% of the haptic in/out group and none of the eyes of the bag-fixated group the IOP rise was more than 10 mmHg. A significantly larger proportion of sulcus-fixated eyes had anterior chamber cells and capsular debris after capsulotomy (chi 2 test, p < 0.001). In the haptic in/out group significant correlation (-0.56, p = 0.009) between IOP rise at 1 hour and the percentage enclosure of the IOL by the anterior capsule was demonstrated. There was no significant difference in maximum IOP rise between glaucomatous and non-glaucomatous eyes (Mann-Whitney U-test, p = 0.49).

Acute Disease↗
PubMed1997

Primary open angle glaucoma and hypothyroidism: chance or true association?

The prevalence of hypothyroidism in British patients with primary open angle glaucoma (POAG) was examined. A recently reported study from Montreal had shown a significant increase (p < 0.004) in biochemical hypothyroidism (23.4%) in a population of 64 POAG patients compared with controls (4.7%). Mechanisms for a possible causal association between the two diseases are discussed, including mucopolysaccharide deposition in the trabecular meshwork and vasculopathy altering ocular bloodflow. Reports of improved glaucoma control following treatment of hypothyroidism are discussed. This study examined 100 consecutive patients with POAG in a specialist glaucoma clinic. All patients were questioned regarding symptoms of thyroid dysfunction and previous thyroid disease. All patients not already taking thyroxine underwent an assay of thyroid stimulating hormone. The 4% (95% CI 1.1-9.4%) prevalence of overt hypothyroidism in our study shows no clinically significant increase either over controls in the Montreal study or over our local population. We conclude that in our local population there is no evidence for a clinically important association of hypothyroidism with glaucoma.

Aged↗
PubMed2005

A pilot study of deep sclerectomy with implantation of chromic suture material as a collagen implant: medium-term results.

AIMS: A pilot study of the safety and efficacy of deep sclerectomy with a chromic suture implant (DSCI) for open angle glaucoma. METHODS: This prospective trial involved 23 eyes of 16 consecutive patients with uncontrolled open angle glaucoma. The DSCI procedure involved radial suturing of a 2 mm piece of 1/0 chromic suture as an implant. Intraocular pressure (IOP) measurements and eye examinations were performed preoperatively and regularly postoperatively for up to 66 months. RESULTS: The mean follow-up period was 36.3 (SD 19.9) months. The mean preoperative IOP was 26.3 (SD 8.5) mmHg. The mean postoperative IOP was 14.1 (SD 2.8) mmHg at month 12, and 16.5 (SD 2.3) mmHg at 36 months. Complete success rate, defined as an IOP lower than 21 mmHg without medication was 77% of eyes at 36 months. Qualified success rate, defined as an IOP lower than 21 mmHg with medication, was 100% at 36 months. Paired t-test and Wilcoxon test analysis of preoperative vs postoperative IOP at 36 months indicated a significant reduction in IOP. Intraoperative complications included rupture of the trabecular meshwork in seven eyes. Exclusion of these patients from the results analysis revealed a mean follow-up of 37.1 months (SD 9), preoperative mean IOP was 25.9 mmHg (SD 4.1), 12-month mean IOP was 13.4 mmHg (SD 2.8), and 36-month mean IOP 16.6 mmHg (SD 2.1). Early postoperative complications included hyphaema in two eyes and dislocation of implant in one eye. One eye developed a central retinal vein occlusion and cataract progression occurred in one eye. The mean postoperative duration of use of topical dexamethasone was 5.4 months (SD 2). CONCLUSIONS: DSCI using a chromic suture implant provides good control of IOP at medium-term follow-up with few postoperative complications. Prolonged use of postoperative anti-inflammatory medication was necessary.

Aged↗
PubMed2006

Corticosteroid-induced glaucoma: a review of the literature.

The intraocular pressure rise that can complicate the use of topical or systemic corticosteroid has been recognised for 50 years. More recently, following isolation of the myocilin gene (previously known as the trabecular meshwork inducible glucocorticoid response or TIGR gene), there has been renewed interest in this steroid-responsive phenomenon. Furthermore, the currently fashionable use of injectable intraocular steroids in the management of clinically significant subretinal fluid and macular oedema has resulted in an increased incidence. Animal studies, cell biology, molecular biology, and an improved knowledge of genetics have provided a better understanding of the mechanisms behind the response. The purpose of this review is to describe the risk factors for developing corticosteroid-induced glaucoma, to discuss the underlying mechanisms and genetics of the condition and to present management options.

Age Factors↗
PubMed2002

Intracavernous administration of SIN-1+VIP in an in vivo rabbit model for erectile function.

In accordance with the data reporting the identification of nitric oxide synthase (NOS) and vasoactive intestinal polypeptide (VIP) positive nerve fibres in the trabecular meshwork of the corpus cavernosum, we suggest that nitric oxide (NO) and VIP may serve complementary physiological roles in penile erection. Therefore SIN-1 and VIP were administered alone and in combination in an in vivo rabbit model. All rabbits revealed basal pressure values of 5-8 cm H2O intracavernously. In the rabbits intracavernously (i.c.) injected with SIN-1 alone and VIP alone, no adequate erectile responses were observed. Whereas, in the group intracavernously injected with the combination of SIN-1+VIP, erectile responses with mean maximal intracavernous pressure (max. ICP) 52.8 (+/-13.2) cm H2O were noted. These pressure elevations do not statistically diverge (P>0.05) than the ones obtained in the control group administered i.c. injections of the combination of papaverine/phentolamine (mean max. ICP 51 (+/-14.73) cm H2O). Referring to our results, we conclude that the combined use of SIN-1+VIP could play an important role in the physiological treatment of erectile dysfunction.

Animals↗
PubMed2002

Familial amyloidotic polyneuropathy presenting with rubeotic glaucoma.

A 78-year-old man with familial amyloidotic polyneuropathy type I (Met30), presented with rubeotic glaucoma 9 months following an uncomplicated vitrectomy for vitreous amyloidosis. There was retinal neovascularization and extensive retinal vascular closure. In the preceding 9 months, episodes of 'uveitis' and high intraocular pressure are thought to be due to amyloid protein released into the aqueous leading to trabecular meshwork obstruction and high intraocular pressures, thus compounding the ocular ischaemia created by amyloid vascular closure. The patient underwent pan-retinal photocoagulation and Molteno implant surgery. The rubeosis regressed and pressure control was gained but sight was lost.

Aged↗
PubMed2003

Localization of smooth muscle actin in the iridocorneal angle of normal and spontaneous glaucomatous beagle dogs.

PURPOSE: To date, our knowledge of the canine trabecular meshwork (TM) with regard to contractility is incomplete. It is important to understand the potential contractile capability within the TM and possible changes associated with spontaneous hypertensive glaucoma. To that end we have examined the presence of actin, including smooth muscle (SM) actin, in the normal and glaucomatous canine iridocorneal angle (ICA) morphologically and immunohistochemically. METHODS: Sections from the ICAs of 12 Beagles with inherited glaucoma (3 months to 6 years old) and age-matched normal Beagles were treated with target retrieval, protein and power blocked and sequentially incubated with the primary antibody (rat anticanine SM actin) and the secondary antibody (rabbit antirat immunoglobulin), followed by peroxidase labeled streptavidin and incubation with substrate-chromogen solution (AEC). Smooth muscle fibers that lined an artery within canine heart tissue were used as positive controls. Separate specimens were prepared for ultrastructual observation. RESULTS: Ultrastructurally, cells within the inner, posterior region of the corneoscleral TM and outer, posterior region of the uveal TM contained many microfilaments, 6 nm in diameter (i.e. actin). Immunohistochemistry demonstrated that cells within these regions possessed SM actin, having been greatest posteriorly, but extended anteriorly to a lesser extent. In the preglaucomatous affected dog the localization pattern for SM actin was identical to that seen in the normal dogs. With the progression of the disease the pattern disappeared. CONCLUSIONS: The interior presence of myofibroblastic cells within the canine ICA suggests that these cells and the smooth muscle cells of the ciliary body along the same plane of orientation function to facilitate the removal of aqueous humor and are likely to be influenced by vascular mediators. The contractile apparatus for the ICA in the dog with inherited glaucoma appeared identical to that of the normal dog prior to expression of the disease, but weakened as the disease progressed.

Actins↗
PubMed2000

[Late diagnosis of Morquio syndrome. Clinical histopathological findings in a rare mucopolysaccharidosis].

BACKGROUND: The Morquio syndrome is a rare autosomal-recessive mucopolysaccharidosis. The Morquio syndrome is characterized by a reduced activity of N-acetylgalactosamine-6-sulfate-sulfatase (type A), or beta-galactosidase (type B). This deficiency leads to a lysosomal storage disease with accumulation of keratan sulfate und chondroitin-6-sulfate in connective tissue, skeletal system und teeth. Consequently, abnormalities of the skeletal system, aortic valvular disease and dental abnormalities occur. Ophthalmologically, diffuse corneal opacification and alterations of the trabecular meshwork--occasionally leading to glaucoma--can be found. CASE REPORT: A 44-year-old woman asked for perforating corneal transplantation because of corneal clouding on both eyes. Besides, she suffered from dwarfism of unclear reason. The diffuse corneal clouding and the dwarfism suggested a systemic-metabolic disease. Thus, further radiologic and medical investigation was started. RESULTS: Radiologically, a kyphoscoliosis, a pectus carinatum, a luxation of both hips, and a gonarthrosis were recognized. Fibroblast culture of a skin biopsy showed reduced activity of N-acetyl-galactosamine-6-sulfate-sulfatase. This was the proof of Morquio syndrome type A. The explanted corneal button showed granules of acid mucopolysaccharides. Those were in the epithelial and endothelial cells and in the corneal stroma. CONCLUSIONS: To our knowledge, a Morquio syndrome has never been diagnosed with an adult and only after the ophthalmologist gave a hint. This can only be explained by the comparative mild expression of the disease in this patient. Diagnosis of Morquio syndrome is important because the frequent odontoid hypoplasia can lead to a deadly atlanto-axial instability, if not treated.

Adult↗
PubMed2001

[Diffuse melanocytic nevus of the iris and absolute glaucoma].

BACKGROUND: Ferry et al. (8) showed that 35 % of eyes which have been enucleated because of a clinically suspected malignant iris lesion did not reveal a histologically malignant iris tumor. PATIENT: A 43-year old male presented with a blind, painful left eye, which has developed over a time period of 6 months. Ophthalmologic examination revealed the presence of pigmented iris stromal lesions associated with diffuse pigmentation of the chamber angle and the development of absolute glaucoma. A diffuse iridociliary malignant melanoma (ring melanoma) was suspected and the blind painful eye was enucleated. Histologic examination revealed the presence of a benign melanocytic lesion, i.e. a spindle cell nevus of the iris with surface plaques causing diffuse extension of the chamber angle, trabecular meshwork, Schlemm's canal, and the ciliary body. CONCLUSION: The malignant potential of iris lesions may be difficult to assess on clinical grounds only. Histologically, benign melanocytic proliferation may cause diffuse extension into the ciliary body as well as the chamber angle leading to an increase in intraocular pressure. In order to reach a final diagnosis a biopsy of the lesion is necessary.

Adult↗
PubMed2001

[Cellular surgery with laser in ophthalmology. A review].

This is a review of a number of laser methods, allowing to realize strongly localized, atraumatic, molecular, cellular, and subcellular microeffects. New instruments are the laser tweezers and the laser knife to be used with a microscope (microscopical surgery). Laser tweezers allow fixation, by means of the radiation pressure of molecular, cellular, and subcellular elements, of diameters as small as 1 microm. These may be irradiated atraumatically by means of short-pulsed lasers. A reversible damage of the cell membrane allows to introduce living genetic material into living cells and to reversibly modify their genetic behaviour. Micromanipulation/irradiation of living cells by means of the short-pulse laser method of living cells may be optimal in in-vivo fertilization experiments. Short-pulse laser methods have been tentatively introduced in ophthalmology and highly localized effects have been realized in the trabecular meshwork for the treatment of glaucoma and in the retina in retinal pathology.

Humans↗
PubMed2003

[Incidence of ocular manifestations in patients with histologically confirmed systemic sarcoidosis].

BACKGROUND: Intraocular findings in sarcoidosis were described by US studies with 35 % anterior uveitis, 25 % posterior uveitis and 20 - 30 % for late complications in case of first presentation. We report on the spectrum and diagnostic possibilities in 38 German patients. PATIENTS AND METHODS: 38 patients (68 eyes) aged 11 - 58 years (average 42.7 y), who suffered of intraocular manifestations in histological confirmed systemic sarcoidosis (1987 - 1997), were completely evaluated retrospectively. For additional diagnostic tools fluorescein angiography, optical coherence tomography, nuclear magnetic resonance tomography and measurements of angiotensin-converting enzyme, lysozyme and calcium in serum were performed. RESULTS: 15 patients (22 eyes = 32.4 %) had anterior uveitis: granulomatous keratouveitis (10 eyes), granulomas of the iris (6), granulomas of the trabecular meshwork (3) and 22 patients (42 eyes = 61.8 %) an intermediate and posterior uveitis: granulomatous perivasculitis (18 eyes), cystoid maculopathy (8), pars planitis (6), neuroretinitis (4), optic neuritis (3), choroiditis (3). Late complications in case of first presentation were found in 22 patients (39 eyes = 57.4 %): posterior synechiae 14 x, secondary glaucoma 10 x, cataracta complicata 8 x, optic atrophy 6 x, intraocular calcification 1 x. CONCLUSION: Compared to previous studies with heterogeneous ethnic composition, intraocular inflammations with confirmed sarcoidosis in German patients show more than 60 % involvement of the posterior segment. We may speculate on the reasons for these discrepancies as being due to ethnic reasons, age and long-term follow-up. In case of typical ocular signs of sarcoidosis, treatment should be started immediately even without histological confirmation. In some cases histological confirmation is successful 8 years after first presentation.

Adolescent↗
PubMed2005

[Long-term results after selective laser trabeculoplasty -- a clinical study on 269 eyes].

BACKGROUND: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Follow-Up Studies↗
PubMed2005

[Influence of prostaglandins on aqueous humour dynamics and intraocular pressure].

In the glaucoma disease the disturbed trabecular outflow results not only in an increase in the intraocular pressure (IOP) level, but also in an increase in the intraocular pressure fluctuations in the majority of patients. This induces a biomechanical stress that may damage the optic nerve head over time and may result in the typical glaucomatous excavation. Prostaglandin analogues show positive effects on both risk factors. They enhance the uveoscleral outflow of the aqueous humour, improve the trabecular outflow facility and probably the regulatory capacity of the trabecular meshwork itself. This dual mechanism might explain the strong IOP-lowering efficacy of the prostaglandins and their additional property to reduce IOP fluctuations leading to a general improvement of the aqueous humour dynamics. Therefore, it makes sense pharmacologically to combine prostaglandins with those medications that also reduce aqueous humour production.

Animals↗
PubMed2006

[Corneal and conjunctival findings in systemic silver intoxication].

BACKGROUND: Chronic silver intoxication is a rare disease and therefore the typical ocular findings may be missed. Based on a case with severe intoxication, the clinical and histological findings as well as the prognosis in argyria are presented. HISTORY: A 33-years-old-employee of a battery production plant developed a biopsy proven systemic argyria. On slit lamp examination the conjunctiva showed a dark, blue-grey discoloration in the areas of the tear flow and the small conjunctival arteries. Diffuse silver deposits were noticed on the level of Descemet's membrane without endothelial damage. Silver deposits were also visible in the trabecular meshwork. Chemical reaction of the silver particles upon exposure to UV light results in irreversible tissue discoloration. Without options for an effective treatment, early diagnosis and prevention of overexposure are most important. CONCLUSIONS: The typical ocular findings in systemic argyria are helpful in occupational medicine for establishing the correct diagnosis.

Adult↗
PubMed1997

[Pseudoexfoliation syndrome in patients with retinal vein branch and central vein thrombosis].

BACKGROUND: Pseudoexfoliation syndrome is a frequent cause of secondary open-angle glaucoma due to deposition and in situ-production of abnormal extracellular matrix proteins in the trabecular meshwork. Glaucomas itself are a known risk factor for retinal vein thrombosis. In this retrospective study the prevalence of pseudoexfoliation syndrome in patients with branch and central retinal vein thrombosis was investigated. PATIENTS AND METHODS: The records of 332 unselected patients with branch retinal vein thrombosis and 159 with central retinal vein thrombosis, which were seen in our laser out-patient clinic between January 1990 and July 1996, were analysed retrospectively. RESULTS: 6.0% of patients with branch and 6.9% of patients with central retinal vein thrombosis revealed pseudoexfoliation syndrome. The full picture of pseudoexfoliation syndrome was seen in 4.2% of patients with branch and in 4.4% of patients with central retinal vein thrombosis. The prevalence of pseudoexfoliation syndrome increased with age. Twenty percent of patients with branch and 27% of patients with pseudoexfoliation syndrome and branch or central retinal vein thrombosis. The branch retinal vein thrombosis was significantly more often localised at the disk in patients with glaucoma and in patients with pseudoexfoliation syndrome. CONCLUSIONS: Pseudoexfoliation syndrome is a risk factor for retinal vein thrombosis. Pathogenetically the secondary open-angle glaucoma caused by pseudoexfoliation syndrome could be causative for the venous thrombosis.

Adult↗
PubMed1989

[Chamber angle findings following implantation of "chamber angle" supported lenses of the Dubroff and Kelman-Multiflex type].

The authors examined 92 eyes after planned ICCE combined with implantation of anterior chamber lenses on average 16.5 months after surgery (range: 6 to 37 months). Two types of lenses were used, namely Kelman-Multiflex and Dubroff. The tissue reactions at the points of contact of the lens haptics in the chamber angle were classified gonioscopically. Even though it was found that reactive tissue reached the filtering trabecular meshwork in some cases (2% of haptic points of Kelman-Multiflex lenses and 15% of those of Dubroff lenses), no significant increase in intraocular pressure was observed. Comparing advantages and disadvantages as regards facility of implantation as well as the probability of hazardous tissue reactions, neither type can be said to be clearly preferable.

Aged↗
PubMed1987

[Sturge-Weber syndrome: glaucoma with elevated episcleral venous pressure].

The present report describes clinical findings in 13 patients with Sturge-Weber syndrome, 11 of whom had glaucoma (22-52 mm Hg). The episcleral venous pressure (EVP) was high in all glaucomatous eyes (14-23 mm Hg). Tonography showed a marked decrease in outflow facility. The observations suggest that glaucoma in Sturge-Weber syndrome is caused by a) elevated episcleral venous pressure and b) secondary damage of the trabecular meshwork with reduction of outflow facility. The cause and pathogenesis of these lesions are discussed. In nine patients a diffuse angiomatosis involving most of the choroid (1.5-4.0 mm thick), as well as the episcleral perilimbal plexus, was demonstrated by ultrasonography.

Adolescent↗
PubMed1985

[Circular, small spot argon laser coagulation of the ciliary body band to lower pressure in open-angle glaucoma].

Approximately 100 argon laser coagulations, 50 microns, 0.1 s, 0.5 to 0.8 W depending on pigmentation, performed on the ciliary band in a circular pattern, cause traction on the scleral spur; this causes the inner wall of Schlemm's Canal to become tensioned, preventing collapse and reducing the outflow resistance from the anterior chamber to Schlemm's canal by widening the trabecular meshwork. When use of this method is indicated the results are good in the vast majority of cases. During a follow-up period of between 5 months and 2 years pressure was lowered on average by 7 mm Hg in 95 out of 101 eyes. In 6 eyes a fistulizing operation was necessary to lower pressure to the required level.

Ciliary Body↗