Modern concepts in antiglaucomatous implant surgery.

BACKGROUND: Antiglaucomatous implant surgery is a continously evolving field in glaucoma treatment. METHODS: A literature search with the terms "glaucoma implant surgery", "aqueous shunts" and "glaucoma drainage devices" was carried out, especially giving prominence to innovative surgical developments in glaucoma implant surgery and to recently established clinical evidence on traditional shunt surgery. RESULTS: Episcleral glaucoma drainage devices have recently proven their efficacy in large studies. Longterm data about their clinical efficacy and their risk/safety profile are sufficiently available. New antiglaucomatous devices try to target alternative drainage routes, for example trabecular or uveoscleral outflow. Valid longterm data from prospective randomized clinical trials are not available for these devices as yet. CONCLUSIONS: Although valid data on clinical application of the new glaucoma implants are not available as yet, profound knowledge about their theoretical concept and their practical management is obligatory for all glaucoma clinicians.

[Lateral tube repositioning following a Baerveldt glaucoma implant. An alternative surgical procedure in the case of repeated conjunctival arrosion]. / Seitliche Schlauchverlagerung beim Baerveldt-Implantat. Eine chirurgische Alternative bei rezidivierender Bindehautarrosion.

Conjunctival arrosion of the silicone tube following glaucoma implant surgery is a postoperative complication that generally requires surgical revision by means of a sclera or dura patch with mobilization of adjacent conjunctiva. We present a case of repeated conjunctival arrosion following Baerveldt implant surgery, in which successful revision was achieved over the course of a year by changing the insertion site of the silicone tube into the anterior chamber without touching the plate of the glaucoma implant. However, a long enough silicone tube is absolutely essential if this strategy is to work.

[The effect of brimonidine on the pupillary reflex. A pupillographic study in healthy volunteers]. / Beeinflussung der Pupillenreaktion durch Brimonidin. Eine pupillographische Studie an Normalpersonen.

PURPOSE: The effect of brimonidine in comparison with acetazolamide on pupillary reflex was investigated in 18 volunteers. METHODS: Infrared pupillography was performed with white diode light of 200 ms duration to measure pupil diameter, constriction latency, reaction time, constriction amplitude, and relative constriction amplitude. The measurements were performed according to a fixed schedule including a phase without medication to determine the baseline level. Data were analyzed by Student's paired t-test. RESULTS: Application of brimonidine and acetazolamide led to a significantly reduced intraocular pressure as well as static and dynamic differences in the pupillary reflex. The pupil diameter measurements were significantly smaller after both medications in comparison to baseline. The reduction of pupil diameter after brimonidine led to significantly reduced contraction amplitude and prolonged latency. CONCLUSION: Application of brimonidine leads to significant miosis, which might due to the affinity to alpha(2)-receptors with reduction of noradrenaline release in the synapse. This effect may play a role in a higher decrease of intraocular pressure by increasing aqueous humor outflow in comparison to clonidine and apraclonidine, but further investigations are required.

[Patient characteristics in a tertiary glaucoma center. Circumstances of treatment and attitudes of patients]. / Profil einer universitären Glaukomsprechstunde. Objektive Behandlungsumstände und subjektive Einstellungen der Patienten.

BACKGROUND: In order to look for conceptual improvements in the practical management of patients sent to our glaucoma department, we analyzed the structures, behaviour, and knowledge about the disease in this patient group. METHODS: Glaucoma patients who were sent for the first time to our department were included prospectively. Before being examined 129 patients were asked to answer a questionnaire concerning their individual characteristics, their behaviour, and patterns of treatment. RESULTS: Of the patients 74% had open-angle glaucoma (including normal tension, exfoliative, and pigment glaucoma), 22% had secondary glaucoma (including neovascular, congenital, and chronic closed-angle glaucoma), and 4% had suspected glaucoma. Written documentation of previously performed intraocular pressure measurements was not available for 84% of the patients. Younger patients had significantly more knowledge about glaucoma and used more possibilities to get information about the disease than elder patients. CONCLUSION: Education about glaucoma disease should be optimized especially for elder glaucoma patients. Documentation of intraocular pressure measurements is insufficient in our patient group.

Trabecular aspiration. A new mode to treat pseudoexfoliation glaucoma.

PURPOSE: The primary cause of intraocular pressure (IOP) elevation in pseudoexfoliation glaucoma is obstruction of the intertrabecular spaces by exfoliation material. The aim of the current study was to evaluate the efficacy of a novel surgical approach--trabecular aspiration--for the management of pseudoexfoliation glaucoma. METHODS: Twelve patients characterized by medically uncontrolled IOP level in pseudoexfoliation glaucoma underwent trabecular aspiration as a primary antiglaucomatous procedure. Aspiration treatment of the meshwork was performed in the inferior circumference of the chamber angle using a specially designed irrigation-aspiration device to fit the chamber angle. Trabecular debris and pigment were cleared with a suction force of 100 to 200 mm Hg. RESULTS: Before surgery, IOP ranged from 24 mm Hg to 52 mm Hg (mean, 37.4 mm Hg). Fifteen months after surgery, IOP ranged from 15 mm Hg to 23 mm Hg (mean, 18.3 mm Hg), which is equivalent to an absolute decrease of 18.7 mm Hg (50%). After surgery, the IOP of 10 eyes was less than 21 mm Hg, although 6 of these eyes still required topical medication. Two eyes attained a final IOP of 24 mm Hg. All treated eyes were aspirated once. Mean antiglaucomatous medication decreased from 4.3 medications daily before surgery to 1.39 medications daily at 15 months after surgery. CONCLUSIONS: This new surgical modality, removing intertrabecular and pretrabecular debris of the trabecular meshwork, can be effective in the management of pseudoexfoliation glaucoma. However, long-term follow-up and extended sample size must be prospected for further clinical evaluation.

The peripheral and central neural actions of clonidine in normal and glaucomatous eyes.

The peripheral and central neural actions of clonidine on normal and glaucomatous eyes have been investigated. Threshold doses of clonidine applied topically induced a monotonic decrease of intraocular pressure in the treated eye and had no effect on the contralateral eye. With increased clonidine dose, a decrease of intraocular pressure occurred in the untreated eye, and there was a concomitant decrease of systemic arterial blood pressure. Analysis of aqueous humor dynamics showed that the ocular response to the peripheral and the central neural actions of clonidine were without effect on the tonographic coefficient of outflow facility. The episcleral venous pressure decreased in both the treated and the untreated eyes, but the changes were too small to account for the observed decrease of intraocular pressure. The results are consistent with the concept that both the peripheral and central ocular hypotensive actions of clonidine are mediated by an inhibition of adrenergic neurogenic vasoconstriction in the eye.

Effect of latanoprost and timolol on the histopathology of the rabbit conjunctiva.

PURPOSE: Long-term medical treatment of glaucoma has an effect on the conjunctiva, possibly affecting the outcome of subsequent filtering surgery. The type and extent of these tissue changes caused by frequently used medications is important. An animal study using rabbits was performed to assess the tissue changes caused by timolol, latanoprost, and a combination of both substances. METHODS: Rabbits were treated with timolol, latanoprost, or a combination of these drugs for 18 months. Conjunctival specimens were examined by light microscopy, quantitative transmission electron microscopy, and immunohistochemistry with antibodies against matrix metalloproteinase (MMP)-3 and tissue inhibitors of metalloproteinase (TIMP)-2. RESULTS: By electron microscopy, the area of subepithelial collagen was significantly larger (P: < 0.03; Mann-Whitney test) in timolol-treated eyes (71.6%) than in control (52.7%) and latanoprost-treated eyes (57.7%). An increase of amorphous material was present in timolol-treated eyes (25.6% versus 7.6% in the controls) as well as a smaller area of empty spaces (2.5% versus 39.4% in control eyes). Latanoprost-treated eyes had no significant increase of empty spaces but showed a marked staining for MMP-3 in the conjunctiva. This staining was not present in control or timolol-treated eyes. Morphologically, degenerative changes of fibrocytes were seen in timolol-treated eyes only. CONCLUSIONS: A significant increase of subepithelial collagen density was present in timolol-treated eyes, whereas this finding was not apparent in latanoprost-treated eyes. Latanoprost-treated eyes showed an upregulation of MMP-3, which may be the reason for reduced extracellular matrix accumulation in such eyes. The morphologic feature of increased subepithelial collagen density and extracellular matrix changes may relate to failure of filtering blebs.

Postoperative application of mitomycin for trabeculectomies.

BACKGROUND: Persistent hypotony is a severe complication following trabeculectomy with intraoperative application of mitomycin. OBJECTIVE: To reduce this rate of hypotony by using a lower concentration of mitomycin and applying the mitomycin only topically to the filtering bleb following surgery. METHODS: Patients were enrolled on a consecutive basis and prospectively followed up. Standard trabeculectomies were performed and mitomycin applied postoperatively on the 3 days following surgery (group 1). For comparison, data from previous studies were used for control eyes with intraoperative mitomycin application (group 2) and no mitomycin application (group 3). Preoperative and postoperative data, complications, and the need for further surgical procedures were evaluated. RESULTS: The study group (group 1) consisted of 22 cases. The mean follow-up was 13.4 and 13.5 months for groups 1 and 2, respectively. Average intraocular pressure values decreased from 33. 6 and 31.0 mm Hg (P =.32; t test) to 16.0 and 12.5 mm Hg in the 2 groups (P =.03; t test). The average number of medications decreased from 2.5 and 2.5 to 0.6 and 0.4 (P =.35; t test) in groups 1 and 2, respectively, at the last visit. Hypotony lasting for more than 3 months occurred only in eyes with intraoperative mitomycin application (14/22). Choroidal detachment (3/22) and hypotony maculopathy (2/22) also were only noted in eyes from group 2. In group 3, success rates were much lower. CONCLUSIONS: This is the first clinical study, to our knowledge, to evaluate the efficacy of this new technique of mitomycin application. From the results, it appears that the postoperative application of mitomycin following trabeculectomy is associated with a lower risk of severe and long-standing hypotony. This technique may be promising in eyes at low risk for failure.

Comparative study of trabecular aspiration vs trabeculectomy in glaucoma triple procedure to treat pseudoexfoliation glaucoma.

OBJECTIVES: To establish the relative safety and effectiveness of trabecular aspiration in combination with phacoemulsification and intraocular lens (IOL) implantation (asp+IOL) for decreasing intraocular pressure (IOP), and to compare the outcome of this method of treatment with that of phacoemulsification and IOL implantation alone (IOL-alone) or standard filtering glaucoma triple procedure (triple procedure). DESIGN: Prospective, controlled study randomized with respect to assignment to trabecular aspiration, with a case-control design between the asp+IOL and triple procedure groups. PARTICIPANTS: Seventy-four eyes of 74 patients with uncontrolled pseudoexfoliation glaucoma without a history of previous intraocular or extraocular surgery and in need of cataract surgery. Forty-eight patients were randomized to those receiving adjunctive trabecular aspiration (asp+IOL group of 26 eyes) and those given no trabecular aspiration (IOL-alone group of 22 eyes). The triple procedure group consisted of 26 cases, closely matched to the asp+IOL cases in terms of age, sex, cup-disc ratio, glaucoma medication requirements, and systemic diseases. INTERVENTIONS: Temporal clear corneal phacoemulsification and foldable IOL implantation was performed in all eyes. In the asp+IOL group, trabecular aspiration was performed with a suction force of 100 to 200 mm Hg under light tissue-instrument contact using a modified intraocular aspiration probe. A modified Cairns-type trabeculectomy without adjunctive antimetabolites was performed superiorly in the triple procedure eyes after IOL implantation. MAIN OUTCOME MEASURES: Surgical outcome was assessed in terms of IOP change, need of adjunctive glaucoma medication, visual acuity outcome, and complications. Surgical failure was defined as an outcome requiring additional surgical intervention or more than 1 medication to achieve IOP control to the target pressure. RESULTS: Two years after surgery, success rates were 36%, 64%, and 78% in the IOL-alone, asp+IOL, and triple procedure groups, respectively (P<.001). Hyphema (46%) and ocular hypotony (11%) were observed in the triple procedure group only, whereas blood reflux (61%) and descemetolysis (19%) were seen exclusively in the asp+IOL group. CONCLUSIONS: In pseudoexfoliative eyes, asp+IOL is significantly more effective than cataract surgery alone in reducing postoperative IOP and the necessity for glaucoma medication. Although trabecular aspiration in the triple procedure did not achieve pressure control in all patients, especially in the low target pressure range, the risk profile appears to be more favorable in the trabecular aspiration-treated eyes than in the filtering glaucoma triple procedure group. Trabecular aspiration in the glaucoma triple procedure could serve as a possible first-line treatment for pseudoexfoliative eyes with coexisting cataract and glaucoma.

Clinical dose-regimen studies with latanoprost, a new ocular hypotensive PGF2 alpha analogue.

This review summarizes recent short-term clinical studies evaluating the ocular hypotensive efficacy of different dose-regimens of latanoprost. When tested in ocular hypertensive and glaucoma patients concomitantly treated with timolol, 0.006% latanoprost given only in the evening, was found to be more effective than the same concentration given in the morning and evening. In patients with open angle, pseudoexfoliation and normal tension glaucoma not receiving other treatment, once-daily 0.005% latanoprost monotherapy was more effective than twice-daily 0.0015% latanoprost treatment. No significant differences were found in conjunctival hyperemia, sensory irritation or blood-aqueous barrier permeability between these two treatment regimens. Although the ocular hypotensive efficacy of once-daily application of the lower concentration (0.0015%) latanoprost was not investigated, we would conclude, based on the studies reviewed here, that at a concentration of 0.005%, once-a-day dosing of latanoprost is highly effective in significantly reducing intraocular pressure, causing only minimal, clinically acceptable short-term ocular side effects.

Quantitative morphologic and functional evaluation of the optic nerve head in chronic open-angle glaucoma.

Glaucoma leads to morphologic changes of the optic nerve head and to functional defects. Morphologic changes in the three-dimensional surface structure of the optic nerve head at its entrance site into the globe can be examined by laser scanning tomography. The standard technique for evaluating functional defects in glaucoma is static computerized perimetry. We compared these two techniques to determine which is more sensitive for follow-up of glaucomatous damage of the optic nerve head. If decreased function is presumed to precede imminent cell death, visual field analysis should be the more sensitive method, as cell death results in absolute defects of the visual field. However, the neuronal networks do not necessarily function in this way. In the case of loss of individual elements in the neuronal network, the complex linkages, even at the retinal level, are able to maintain functions and compensate for loss of function, which means that visual field defects would not be prominent. If the damage increases with time and is accompanied by a progressive loss of ganglion cells, however, compensation is eventually no longer possible, and the functional defects then become measurable by visual field analysis. Thus, morphologic absolute changes may be more prominent than visual field defects in the early stages of glaucoma. To evaluate the quantitative relationship between morphometrically measurable defects of the optic nerve head and measurable functional defects, we first examined the visual field with static computerized perimetry and then evaluated the surface structure with a laser scanning tomograph in 90 patients with chronic open-angle glaucoma, 10 patients with ocular hypertension, and 10 patients without any eye disease. Based on the 95th percentile of the standardized rim/disk area ratio, we calculated the relative rim area loss and correlated this with the mean defect in visual field analysis. The scatterplot shows an exponential curve. In the early stages of glaucoma, visual field defects were less prominent than morphologic absolute changes; 40% of the neuroretinal rim area is lost by glaucomatous optic nerve damage before first defects in visual field analysis appear. In late stages of glaucoma, changes in perimetry are more prominent than those observed with biomorphometry. These results show that in the follow-up of patients with early stages of glaucomatous damage, special attention should be given to morphologic absolute changes. In patients with advanced glaucoma, progress of the damage should be observed by repeated functional, rather than morphologic, examinations. It is important to keep in mind, however, that the sensitivity of any method is dependent on technology. One reason why functional tests may not be as sensitive as morphologic examination in observing patients with early stages of glaucoma may simply be that functional tests are not yet sensitive enough to detect early damage.

Measuring drug-induced eye irritation: a simple new clinical assay.

Thirty-six normal subjects received a drop in either eye of two of four ophthalmic solutions, balanced saline (S), carteolol, 1% (C1), carteolol, 2% (C2), or timolol, 0.5% (T), in a double-blind, randomized trial in a balanced incomplete block design. Subjects reported immediately, at three, and again at ten minutes after administration whether one eye felt more irritated and marked an analog scale of irritation. An observer also made ratings at three minutes based on responses to stereotyped questions. Significant differences in irritation between timolol and each of the other drugs and placebo were shown by analog scale scores immediately after instillation of the solutions. Maximum likelihood estimates were calculated based on statements of subject preference, and a significant preference was demonstrated. Observer ratings also demonstrated a treatment effect. This simple clinical assay system provides a new, valid method for estimating irritation induced by ophthalmic solutions.

Electrophysiologic abnormalities in two cases of familial amyloidosis.

PURPOSE/METHODS: We recorded electrophysiologic data of two patients with familial amyloidosis. RESULTS/CONCLUSIONS: Only minor abnormalities could be demonstrated clinically and by means of fluorescein angiography in one patient. Considerable alterations of electrophysiologic responses could be found in both patients. These results suggest that an early retinal or optic nerve involvement in amyloidosis could be detected by using these noninvasive techniques.

A double-masked comparison of carteolol and timolol in ocular hypertension.

We performed a double-masked study in which 98 patients with ocular hypertension who had been previously treated with timolol received either timolol 0.25% or carteolol 1%, a beta-blocker with intrinsic sympathomimetic activity. The drugs were administered topically twice daily for one month after a one-week washout period. Intraocular pressure was measured at baseline and after one and four weeks of treatment. The appearance of the fundus, external eye, visual fields, tear secretion, blood pressure, and pulse were recorded. Adverse symptoms were elicited using a menu-type questionnaire and an overall judgment of therapy was recorded. Carteolol was as effective as timolol in reducing intraocular pressure. There were significantly fewer patients reporting adverse events overall (P = .019), and eye irritation specifically (P = .02), in the group treated with carteolol.

Prospective study of ab externo erbium:YAG laser sclerostomy in humans.

PURPOSE: To evaluate the efficacy of ab externo erbium:YAG (Er:YAG) laser sclerostomy in controlling intraocular pressure in eyes with uncontrolled glaucoma. METHODS: We performed ab externo laser sclerostomy on eyes of 26 patients. Mean +/- SD postoperative follow-up was 11.4 +/- 0.9 months. Complete success was defined as intraocular pressure below 22 mm Hg with no adjunct medication; qualified success was defined as intraocular pressure below 22 mm Hg with medication. RESULTS: In all eyes, ab externo Er:YAG laser sclerostomy achieved a functioning fistula with a prominent filtering bleb. Twelve eyes had had neodymium:YAG (Nd:YAG) laser iridotomy at the site of laser sclerostomy 2 weeks before filtering surgery; 14 eyes had surgical iridectomy at the site of laser sclerostomy. Mean preoperative intraocular pressure of 30.7 +/- 7.3 mm Hg (range, 17.0 to 48.0 mm Hg) was significantly (P < .05) reduced to 18.3 +/- 1.0 mm Hg (range, 0 to 25.0 mm Hg) at 2 weeks postoperatively. thereafter, marked regression was noted: at 1 month postoperatively, intraocular pressure was 20.1 +/- 9.5 mm Hg (range, 4.0 to 44.0 mm Hg); half-life of complete success was 25 days; of qualified success, 56 days; and of a functioning filtering bleb, 36 days. CONCLUSIONS: Ab externo Er:YAG laser sclerostomy reliably created successful full-thickness fistulae with prominent filtering blebs in human glaucomatous eyes. However, a transient phase of ocular hypotony caused by aqueous overfiltration, followed by an ongoing rate of fistula patency failure, renders Er:YAG laser sclerostomy, as performed in this study, unsuitable for long-term pressure control.

Corneal injury after carbon dioxide laser skin resurfacing.

PURPOSE: To describe a corneal injury in both eyes of a patient who had undergone carbon dioxide laser skin resurfacing. METHOD: Case report. RESULTS: A 67-year-old woman had severe pain and decreased vision in both eyes after undergoing laser skin resurfacing treatment with a pulsed carbon dioxide laser. Clinical examination disclosed a corneal ulcer, a bullous keratopathy, and intrastromal bleeding. After perforating keratoplasty, the histologic examination of the cornea showed signs of thermal injury. CONCLUSIONS: The results of the histologic examination and the onset of symptoms within 24 hours after therapy suggest that the laser application caused the corneal damage. Safety guidelines for this procedure should be reviewed.

Goniocurettage for removing trabecular meshwork: clinical results of a new surgical technique in advanced chronic open-angle glaucoma.

PURPOSE: To elucidate the long-term outcome of goniocurettage as a new technique in trabecular microsurgery for advanced open-angle glaucoma. METHODS: In a prospective, nonrandomized clinical trial, 25 eyes of 25 patients with a mean age +/- SD of 72.7+/-10.1 years (range, 50 to 89 years) with uncontrolled chronic open-angle glaucoma that had undergone failed filtering procedures were treated by goniocurettage. Trabecular tissue was scraped away from the chamber angle by means of an instrument similar to a microchalazion curette (diameter, 300 microm). RESULTS: Before surgery, intraocular pressure ranged from 29 to 48 mm Hg (mean +/- SD, 34.7+/-7.1 mm Hg), and mean number of antiglaucoma medications was 2.2+/-0.56. Follow-up averaged (+/-SD) 32.6+/-8.1 months (range, 30 to 45 months). Overall success, defined as postoperative intraocular pressure of 19 mm Hg or less with one pressure-reducing agent, was attained in 15 eyes (60%), with five eyes (20%) being controlled without medication. Considering all successfully treated patients, the mean intraocular pressure was 17.7+/-3.1 mm Hg (range, 10 to 19 mm Hg) at the final visit. Mean intraocular pressure reduction was 17.1+/-7.1 mm Hg in these eyes, representing a net decrease from baseline of 49%. Number of antiglaucoma medications dropped to 0.63+/-0.29. Complications included localized Descemet membrane detachment in five eyes (20%) and moderate anterior chamber bleeding in four eyes (16%). CONCLUSIONS: This new surgical technique can effectively control intraocular pressure for long periods of time in patients with open-angle glaucoma and a history of failed filtering procedures. Goniocurettage may be a suitable alternative to surgical treatment of glaucoma patients with excessive conjunctival scarification.

Risk factors for failures of trabeculectomies performed without antimetabolites.

AIMS: To assess the risk profile for the failure of trabeculectomies in a large group of patients who were selected to be operated on without the use of antimetabolites. This was done in an effort to find subgroups of patients who may not need antimetabolites for primary procedures. METHODS: Consecutive patients scheduled for routine trabeculectomies were operated during a 4 year period and were followed up for at least 6 months postoperatively. Patients were regularly examined in the glaucoma unit and by their local ophthalmologists. Pre- and postoperative data were evaluated and success rates determined. RESULTS: 709 eyes of 566 patients were operated on; 534 eyes of 534 patients (94.4%) were finally evaluated. The mean follow up was 27.9 (SD 13.6) months with a range of 6-62 months. Success rates for complete surgical success ranged from 59% in the best group with pigmentary dispersion syndrome to 0% in the worst group with neovascular glaucoma. Success rates of patients with POAG, pseudoexfoliation, chronic angle closure, pigmentary dispersion syndrome, and dysgenetic glaucoma were similar. Failure rates ranged from 11% in the best group (pseudoexfoliation) to 80% in the worst group (neovascular glaucoma). Failure rates were high in complicated forms of glaucoma such as traumatic (30%), buphthalmus (40%), and uveitic (50%). For repeat trabeculectomies, the failure rate was 49% (20 of 41 eyes). The mean time until failure ranged from 2.7 months (traumatic) to 15.5 months (pigmentary dispersion syndrome) and was 4.9 months for repeat trabeculectomies. CONCLUSION: Trabeculectomy performed in selected groups of patients has a favourable outcome without the use of antimetabolites. It may be possible to avoid antimetabolites in these groups of patients for primary procedures.

Morphological variability of the trabecular meshwork in glaucoma patients: implications for non-perforating glaucoma surgery.

BACKGROUND/AIMS: Morphological variability of the trabecular meshwork could be of considerable importance for the proper intraoperative outcome of non-perforating antiglaucomatous surgery, such as deep sclerectomy and viscocanalostomy. The aim of this study was therefore to assess qualitative and quantitative characteristics of the trabecular meshwork in glaucoma patients undergoing trabeculectomy. METHODS: Trabeculectomy specimens from 177 glaucoma patients were prepared for light microscopy; 100 specimens were found to be suitable for qualitative assessment and quantitative computerised image analysis; measurements were taken of the meridional diameter of Schlemm's canal as well as the thickness of the trabecular meshwork at different positions. RESULTS: The mean meridional diameter of Schlemm's canal was 290 microm with the smallest values in the young patients with infantile and secondary glaucomas. the thickness of the trabecular meshwork ranged between 50-70 microm in the anterior region and between 100-130 microm for the posterior portion. The thickness of the anterior meshwork significantly decreased with age. The pigmentation of excised trabecular meshwork was found to be weak or even lacking in 68 patients. In 20 glaucoma patients the uveal meshwork was covered by an endothelial layer. CONCLUSIONS: From the morphological point of view the risk of inadvertent perforation during deep sclerectomy in older, white glaucoma patients should be taken into account even by an experienced surgeon, because the anterior meshwork in these cases is very thin and trabecular pigmentation that can be used as a topographic landmark is often lacking. The functional success of non-perforating glaucoma surgery in many patients may be limited by endothelial covering of the trabecular meshwork.

Photodynamic modulation of wound healing in glaucoma filtration surgery.

AIM: To report a clinical pilot study investigating photodynamic therapy (PDT) in combination with glaucoma filtration surgery. BCECF-AM was used as the photosensitising substance. The clinical safety and tolerability of BCECF-AM, and its efficacy in controlling postoperative intraocular pressure (IOP) were assessed. METHODS: Before trabeculectomy (TE), 42 consecutive eyes of 36 glaucoma patients received one subconjunctival injection of 80 micro g BCECF-AM (2,7,-bis- (2-carboxyethyl) -5- (and-6) -carboxy-fluorescein, acetoxymethyl-ester) followed by an intraoperative illumination with blue light (lambda = 450-490 nm) for 8 minutes. Antifibrotic efficacy was established as postoperative IOP reduction of >20% and/or an IOP constantly < 21 mm Hg without antiglaucomatous medication. Follow up of the filtering bleb was documented by slit lamp examination. RESULTS: Eyes had mean 1.1 preoperative surgical interventions (filtration and non-filtration glaucoma surgery). Mean preoperative IOP was 31.6 (SD 9.7) mm Hg. Patients were followed for mean 496 days (range 3.5-31.8 months). Of the 42 eyes, 25 eyes had an IOP decreased to 15.8 (3.4) mm Hg without medication (complete success: 59.5%; p<0.001; t test). Seven eyes showed good IOP reduction < 21 mm Hg under topical antiglaucomatous medication (qualified success: 16.7%). 10 eyes failed because of scarring within 2-67 weeks (23.8%). Clinical follow up examinations revealed no local toxicity, no uveitis, and no endophthalmitis. CONCLUSIONS: This method is a new approach in modulating postoperative wound healing in human eyes undergoing glaucoma filtration surgery. The data of the first human eyes combining TE with PDT underline the clinical safety of this method and its possible potential to prolong bleb survival.