Adverse effects of topical antiglaucomatous medications on the conjunctiva

Switching from a preserved to a preservative-free prostaglandin preparation in topical glaucoma medication

PURPOSE

The purpose of this study was to investigate the tolerability and intraocular pressure (IOP) reducing effect of the first preservative-free prostaglandin tafluprost (Taflotan) in patients exhibiting ocular surface side-effects during latanoprost (Xalatan) treatment.

METHODS

A total of 158 patients were enrolled in this open-label multicentre study. Eligible patients had to have at least two ocular symptoms, or one sign and one symptom, during treatment with latanoprost. At baseline, the patients were directly switched from latanoprost to preservative-free tafluprost for 12 weeks. The patients were queried for ocular symptoms, and ocular signs were assessed by using tear break-up time, Schirmer's test, fluorescein staining and evaluation of conjunctival hyperaemia and blepharitis. In addition, HLA-DR and MUC5AC in conjunctival impression cytology specimens were analyzed, and a drop discomfort/quality of life (QoL) questionnaire was employed. IOP was measured at all visits.

RESULTS

Preservative-free tafluprost maintained IOP at the same level after 12- weeks treatment (16.4 +/- 2.7 mmHg) as latanoprost at baseline (16.8 +/- 2.5 mmHg). During treatment with preservative-free tafluprost, the number of patients having irritation/burning/stinging (56.3%), itching (46.8%), foreign body sensation (49.4%), tearing (55.1%) and dry eye sensation (64.6%) decreased to 28.4%, 26.5%, 27.1%, 27.1% and 39.4% correspondingly. The number of the patients with abnormal fluorescein staining of cornea (81.6%) and conjunctiva (84.2%), blepharitis (60.1%), conjunctival hyperaemia (84.2%) and abnormal Schirmer's test (71.5%) was also reduced significantly to 40.6%, 43.2%, 40.6%, 60.0% and 59.4% correspondingly. The tear break-up time improved significantly from 4.5 +/- 2.5 seconds to 7.8 +/- 4.9 seconds. A reduction in the number of patients with abnormal conjunctival cells based on HLA-DR and MUC5AC was also detected.

CONCLUSIONS

Preservative-free tafluprost maintained IOP at the same level as latanoprost, but was better tolerated in patients having signs or symptoms while on preserved latanoprost. Preservative-free tafluprost treatment resulted in improved QoL, increased patient satisfaction and drop comfort.

Incidence, severity and factors related to drug-induced keratoepitheliopathy with glaucoma medications

Purpose

To evaluate the incidence, severity, and factors related to drug-induced keratoepitheliopathy in eyes using antiglaucoma eye drops.

Patients and methods

In a cross-sectional study, 749 eyes from 427 patients who had used one or more antiglaucoma eye drops were examined at Niigata University Medical and Dental Hospital or related facilities. The incidence and severity of superficial punctate keratitis (SPK), patient gender and age, type of glaucoma, and type of eye drops were recorded. SPK was graded according to the AD (A, area; D, density) classification. The severity score (SS) was calculated from A × D.

Results

SPK was observed in 382 (51.0%) of 749 eyes that had received any type of antiglaucoma eye drops. While 254 eyes (33.9%) were classified as A1D1 (SS 1), 34 eyes (4.6%) had severe SPK with SS 4 or more. The number of eye drops and the total dosing frequency per day were significantly greater in SPK-positive eyes than in eyes without SPK. The number of eye drops was proportional to the frequency and severity of SPK. Among eyes that were treated with three or more eye drops, SPK was more severe and more frequent in older patients (≥71 years). In addition, a considerable difference was detected for each type of glaucoma.

Conclusion

Drug-induced keratoepitheliopathy is often observed in eyes that have received recent antiglaucoma eye drops. The number of eye drops, the total dose frequency per day, patient age, and type of glaucoma may affect this condition. We have to consider not only the effects on intraocular pressure but also the incidence and severity of drug-induced keratoepitheliopathy as a frequent side effect of glaucoma medications.

Ocular preservatives: associated risks and newer options

Presence of a preservative in an ocular medication has often been considered a culprit in damaging the epithelium. However, the inclusion of a preservative is equally necessary, especially in multiple-dose containers, in order to protect against dangerous organisms accidentally gaining access during instillation. Benzalkonium chloride (BAK), chlorobutanol, chlorhexidine acetate (CHA), and phenylmercuric nitrate or acetate are some commonly used preservatives in eye preparations. New preservatives with a wide range of activity and good safety profiles have been introduced in the market, such as stabilized oxychloro complex (SOC), sofZia, and sodium perborate. In the present review, we discuss various conventional and newly proposed and patented preservative molecules for ocular use. Reasons for discontinuing traditional preservatives and the need for less-toxic molecules are discussed at length, along with newer options coming up in this area.

The critical role of the conjunctiva in glaucoma filtration surgery

This review considers the critical role of the conjunctiva in determining the success or failure of glaucoma filtration surgery. Glaucoma filtration surgery can be defined as an attempt to lower intraocular pressure (IOP) by the surgical formation of an artificial drainage pathway from the anterior chamber to the subconjunctival space. Many types of glaucoma filtration surgery have been developed since the first attempts almost 180 years ago. The wide range of new techniques and devices currently under investigation is testament to the limitations of current techniques and the need for improved therapeutic outcomes. Whilst great attention has been paid to surgical techniques and devices to create the drainage pathway, relatively little attention has been given to address the question of why drainage from such artificial pathways is often problematic. This is in contrast to normal drainage pathways which last a lifetime. Furthermore, the consequences of potential changes in aqueous humour properties induced by glaucoma filtration surgery have not been sufficiently addressed. The mechanisms by which aqueous fluid is drained from the subconjunctival space after filtration surgery have also received relatively little attention. We propose that factors such as the degree of tissue damage during surgery, the surrounding tissue reaction to any surgical implant, and the degree of disruption of normal aqueous properties, are all factors which influence the successful formation of long term drainage channels from the conjunctiva, and that these channels are the key to successful filtration surgery. In recent years it has been suggested that the rate of fluid drainage from the subconjunctival space is actually the determining factor in the resultant IOP reduction. Improved knowledge of aqueous humour induced changes in such drainage pathways has the potential to significantly improve the surgical management of glaucoma. We describe for the first time a novel type of drainage surgery which attempts to minimise surgical trauma to the overlying conjunctiva. The rationale is that a healthy conjunctiva allows drainage channels to form and less opportunity for inflammation and scar tissue formation which are a frequent cause of failure in glaucoma filtration surgery. Successful drainage over extended periods of time has been demonstrated in monkey and rabbit eyes. Long lasting drainage pathways were clearly associated with the presence of lymphatic drainage pathways. A new philosophy in glaucoma drainage surgery is proposed in which minimisation of surgical trauma to the conjunctiva and the encouragement of the development of conjunctival drainage pathways, particularly lymphatic pathways, are central pillars to a successful outcome in glaucoma filtration surgery.

Pharmacokinetics, efficacy and safety profiles of preserved and preservative-free tafluprost in healthy volunteers

PURPOSE

Prostanoid F(2alpha) (PF(2alpha)) analogues are commonly used as first-line treatment of glaucoma. Tafluprost is a newly synthesized PF(2alpha) derivative and represents the first PF(2alpha) analogue with a fully preservative-free formulation.

METHODS

A randomized, investigator-masked, single-centre, crossover phase I study evaluated the pharmacokinetics, efficacy and safety profiles of preserved and preservative-free tafluprost 0.0015% eyedrops in healthy volunteers. Both formulations were administered once/day for 8 days each. Plasma concentrations and, consequently, area under the curve (AUC(0-last)), maximum concentration (C(max)) and time to maximum concentration (t(max)) were determined for tafluprost acid, the biologically active metabolite. Intraocular pressure, adverse events, and ocular and systemic safety parameters were analysed.

RESULTS

There were no statistically significant differences in pharmacokinetic parameters between preserved and preservative-free formulations after either single (day 1) or repeated (day 8) dosing. The mean (+/- standard deviation) results for preserved and preservative-free formulations on day 8 were, respectively: AUC(0-last) 581.1 +/- 529.9 pg/min/ml versus 431.9 +/- 457.8 pg/min/ml (p = 0.462); C(max) 31.4 +/- 19.5 pg/ml versus 26.6 +/- 18.0 pg/ml (p = 0.294), and median (range) t(max) 10 (5-15) for both. Generally, plasma concentrations of tafluprost acid were low at all time-points and were cleared rapidly from the circulatory system. There were no unexpected safety findings. The incidence of ocular hyperaemia was similar in both formulations and was of predominantly moderate severity with preserved tafluprost and mild severity with preservative-free tafluprost.

CONCLUSIONS

Preservative-free tafluprost appeared to have similar pharmacokinetic properties to the preserved formulation and was generally well tolerated.

Efficacy and safety levels of preserved and preservative-free tafluprost are equivalent in patients with glaucoma or ocular hypertension: results from a pharmacodynamics analysis

PURPOSE

Tafluprost is a new prostaglandin F(2alpha) (PGF(2alpha)) derivative in development for the treatment of glaucoma. Tafluprost is the first PGF(2alpha) analogue with a preservative-free formulation.

METHODS

This randomized, investigator-masked, multicentre, crossover phase III study evaluated the pharmacodynamics and safety of preserved and preservative-free tafluprost 0.0015% eyedrops administered for 4 weeks in 43 patients with open-angle glaucoma or ocular hypertension. The primary variable was change from baseline in overall diurnal intraocular pressure (IOP) at 4 weeks. Adverse events and other safety parameters were also analysed.

RESULTS

Decreased IOP was clearly observed with both formulations at week 1 and was sustained until week 4. The overall treatment difference (preservative-free versus preserved formulations) at week 4 was 0.01 mmHg (95% confidence interval - 0.46 to 0.49; p = 0.96). There were no unexpected safety-related findings. Both formulations were well tolerated and most adverse events were ocular and mild in severity.

CONCLUSIONS

THE reduction in IOP achieved by preservative-free tafluprost is equivalent to that obtained with the preserved formulation. The preservative-free formulation was generally well tolerated.

A randomized prospective study comparing trabeculectomy with and without the use of a new removable suture

INTRODUCTION

The aim of this prospective study is to verify, in terms of both early postoperative complications and intraocular pressure (IOP) outcomes, the performance of a scleral flap removable suture.

MATERIALS AND METHODS

Sixty-six patients that underwent trabeculectomy were randomly divided into two groups: in the first group (group A, 33 eyes) a standard fornix-based trabeculectomy was performed by using a conjunctival chain suture. In the second group (group B, 33 eyes) the same technique was performed with the additional employment of a new removable suture to the scleral flap. The patients were followed-up for 12 months.

RESULTS

After 1 year the mean IOP was 16.58 mmHg (+/-3.73 mmHg) in group A, and 16.12 mmHg (+/-4.21 mmHg) in group B; statistical analysis did not show significant differences between the two groups (P = 0.19). Early postoperative hypotony and shallowing of the anterior chamber were significantly more frequent after standard trabeculectomy than after trabeculectomy using the removable suture (P < 0.02).

CONCLUSIONS

The employment of a fornix-based conjunctival chain suture for the flap allows the use of the removable scleral flap suture, which has proved very effective in preventing insufficient flap resistance with aqueous overdrainage and hypotony, and which is also easy to apply and to remove. Compared with standard trabeculectomy, this device has proved to have similar IOP-lowering efficacy, together with a lower rate of early postoperative complications.

A study of the safety and efficacy of travoprost 0.004%/timolol 0.5% ophthalmic solution compared to latanoprost 0.005% and timolol 0.5% dosed concomitantly in patients with open-angle glaucoma or ocular hypertension

Background/Aims

To compare the intraocular pressure (IOP)-lowering efficacy of travoprost 0.004%/timolol 0.5% in fixed combination with the unfixed combination of latanoprost 0.005% and timolol 0.5% in open-angle glaucoma or ocular hypertension patients with IOP levels below 18 mmHg on the unfixed combination of latanoprost 0.005% and timolol 0.5%.

Methods

Following a 30-day open-label run-in with latanoprost QD PM and timolol QD AM, subjects with intraocular pressure below 18 mmHg were randomized to continue concomitant latanoprost QD PM and timolol QD AM or switch to travoprost 0.004%/timolol 0.5% QD AM and vehicle QD PM in masked fashion and were followed for 3 months. The primary efficacy endpoint was mean IOP reduction from baseline.

Results

There were no clinically relevant or statistically significant differences in mean IOP, mean IOP change from baseline, or percentage IOP change from baseline between the two treatment groups. Between-group differences in mean IOP were within ±0.3 mmHg at all time points (p ≥ 0.384), and between-group differences in mean IOP change from baseline were within ±0.4 mmHg at all time points. Overall, 88% of patients whose IOP was less than 18 mmHg on the unfixed combination of latanoprost and timolol remained well controlled on the same regimen in the masked portion of the study, compared with 92% who remained well controlled after switching to travoprost/timolol.

Conclusion

Travoprost 0.004%/timolol 0.5% administered once daily and concomitant administration of timolol 0.5% and latanoprost 0.005% produce similar maintenance of IOP-lowering effect in patients who were previously well controlled on concomitant administration of latanoprost and timolol. Patients who are well controlled on latanoprost and timolol concomitant therapy can be switched to once-daily therapy with travoprost 0.004%/timolol 0.5% with no expected compromise in the safety and efficacy of their treatment.

Phaco-microtrabeculectomy: technique and intraocular pressure control in comparison with microtrabeculectomy

PURPOSE

To describe a modified technique for combined cataract and glaucoma drainage surgery involving a small flap (micro) trabeculectomy combined with phaco-emulsification (PMT). To assess the level of intraocular pressure (IOP) control achieved by this procedure in comparison with microtrabeculectomy (MT) alone.

METHODS

In this retrospective controlled case series records were reviewed for 37 consecutive low-risk patients undergoing PMT augmented with 5-fluorouracil (5-FU) and 37 low-risk subjects undergoing MT with 5-FU. IOP control was compared by survival analysis using IOP targets < or = 21 mmHg and < or = 16 mmHg at final follow up and with at least a 25% reduction from the preoperative pressure.

RESULTS

Mean follow up was 41.7 months (range 19.0-72.0) in the PMT group and 43.5 months (range 18.0-66.0) in the MT group. A final IOP < or = 21 mmHg and with at least a 25% reduction from the preoperative pressure was achieved in 91.9% patients undergoing PMT (70.3% on no glaucoma drops). IOP < or = 16 mmHg and with at least a 25% reduction from the preoperative pressure was achieved in 67.6% (56.8% without drops). There were no significant differences in survival rates between PMT and MT for either IOP target. The mean final IOPs were 13.4 and 13.5 mmHg on a mean of 0.6 and 0.8 glaucoma drops in the PMT and MT groups, respectively. In the PMT final visual acuity improved by at least one Snellen line in 81.1% and was worse in a single eye.

CONCLUSIONS

IOP control following combined surgery by PMT is as good as following MT alone.

The Ocular Surface of Glaucoma Patients Treated over the Long Term Expresses Inflammatory Markers Related to Both T-Helper 1 and T-Helper 2 Pathways

PURPOSE

To investigate the expression of CCR5 and CCR4, two chemokine receptors, as markers of the T helper (Th) 1 and Th2 pathways, respectively, and class II antigen HLA-DR as a hallmark of inflammation on conjunctival cells obtained from patients receiving long-term glaucoma treatment.

DESIGN

Case-control study.

PARTICIPANTS

A total of 18 normal subjects and 70 glaucoma patients treated with topical antiglaucoma drugs for more than 1 year: 14 receiving a beta-blocker as monotherapy, 38 treated with a prostaglandin analog alone (19 with latanoprost, 6 with travoprost, 13 with bimatoprost), and 18 receiving multiple treatments.

METHODS

Impression cytologic specimens (ICSs) were obtained from 1 eye of the patients and processed for flow cytometry. Conjunctival cells were extracted and incubated with monoclonal antibodies against CCR4, CCR5, HLA-DR, or their specific controls to measure, in a masked manner, the percentages of conjunctival cells positive for the 3 markers.

MAIN OUTCOME MEASURES

HLA-DR and chemokine receptors (CCR4 and CCR5) in ICSs.

RESULTS

Compared with all other groups, HLA-DR expression was raised significantly in the multitreatment group, whereas all monotherapies showed slight and nonsignificant increases. Both CCR4 and CCR5 were increased significantly in all 5 glaucoma groups compared with normal subjects, with no between-group differences.

CONCLUSIONS

This study demonstrates the overexpression of 2 chemokine receptors in the conjunctival epithelium of glaucoma patients treated over the long term. These results show the simultaneous overexpression of CCR4 and CCR5, suggesting that the chronic use of topical treatments may stimulate both the Th1 and Th2 systems simultaneously. These results also suggest that inflammatory mechanisms combining allergy with toxicity are at work and illustrate the complexity of inflammatory reactions occurring in the ocular surface of glaucoma patients.

Effects of Topical Antiglaucoma Medications on Corneal Epithelium as Evaluated by Gene Expression Patterns

PURPOSE

To examine the expression pattern of the stress-related genes c-fos and c-jun, which encode the 2 major components of activator protein (AP)-1, and cyclooxygenase (COX)-2 in rat corneal epithelium treated with topical antiglaucoma medications and benzalkonium chloride (BAK) preservative.

METHODS

Eighty-eight male Wistar rats were used. We instilled antiglaucoma eye drops (0.5% Timoptol, 0.005% Xalatan, or 0.12% Rescula), their chemical constituents (active ingredients), or BAK preservative (0.005%, 0.01%, or 0.02%) in 1 eye of each rat. Fellow eyes served as controls. The eyes were enucleated after various intervals. In situ hybridization and immunohistochemistry were used to detect expression of c-fos, c-jun, and COX-2.

RESULTS

Expression of c-fos, c-jun, and COX-2 was minimally observed in uninjured rat corneal epithelium. Thirty minutes to 1 hour after applying the antiglaucoma eye drops, signals for c-fos and c-jun mRNA were detected in the corneal epithelium. Ninety minutes after applying 0.005% Xalatan, 0.12% Rescula, or their chemical constituents, but not 0.5% Timoptol, COX-2 was detected in corneal epithelium. Expression of c-fos and c-jun seemed more marked with prostaglandins than with timolol. Thirty minutes to 1 hour after instillation of 0.02% BAK preservative, signals for c-fos and c-jun mRNA were detected in the corneal and conjunctival epithelium. COX-2 was not induced by 0.5% Timoptol or BAK preservative. COX-2 mRNA was not affected by applying 0.005% or 0.01% BAK preservative. Proteins of these components were also detected, indicating that each mRNA expression was followed by protein synthesis.

CONCLUSIONS

Corneal and conjunctival epithelial cells are transcriptionally activated transiently at an early phase after topical administration of antiglaucoma medications and BAK preservative. Stimulatory effects of prostaglandin drugs on corneal epithelial cells were more marked than those with timolol. Expression of COX-2 may potentially be involved in inflammatory response in the corneal epithelium.

Effects of topical antiglaucoma medications on the ocular surface

The side effects of topical antiglaucoma medications and their preservatives range from ocular discomfort to sight-threatening alterations of the ocular surface. Conjunctival hyperemia, decreased tear production and function, and superficial punctate keratitis are among the most common signs seen on routine clinical examination. Squamous cell metaplasia and changes in cell morphology have been demonstrated by impression cytology studies and evaluation of biopsy specimens, and inflammatory effects are documented by the presence of inflammatory markers. The adverse effects of topical antiglaucoma eyedrops interfere with the treatment of glaucoma on two levels: first, the discomfort produced by the eye drops discourages patient compliance; and, second, long-term treatment with eyedrops is associated with a higher failure of filtration surgery. The detailed mechanism of inflammatory response and/or direct toxicity of eye drops has yet to be determined, but it may vary with the different classes of eye drops, different preservatives, and durations of treatments. Upcoming multicenter trials for new antiglaucoma eye drops should specifically evaluate ocular surface effects.

[Activation of TH1/TH2 pathways detected through the expression of CCR4 and CCR5 on the ocular surface of glaucomatous patients treated over the long term]

PURPOSE

The aim of this work was to study, using flow cytometry, the expression of two chemokine receptors, CCR4 and CCR5, known to be related to the TH2 and TH1 systems, respectively, and the expression of HLA-DR, a hallmark of inflammation, on conjunctival impression cytology specimens (ICS) of glaucomatous patients treated over the long term.

PATIENTS AND METHODS

In this case-control study, ICS were taken in a series of 35 glaucomatous patients treated with topical antiglaucoma drugs for more than 1 year (seven with beta-blockers, ten with prostaglandins, and 18 receiving multiple treatments), and 20 normal subjects. Conjunctival cells were collected and incubated with specific monoclonal antibodies directed against CCR4, CCR5, and HLA-DR, in order to measure, in a masked manner using flow cytometry, the percentage of cells positive to each marker in the conjunctival epithelium.

RESULTS

Compared to normal subjects, HLA DR expression was significantly elevated in glaucomatous patients, with a tendency toward higher levels in the multitreatment group and lower levels in patients treated with prostaglandins, which did not differ significantly from control values. Both CCR4 and CCR5 significantly increased in glaucoma patients on multitreatment or monotherapy compared with normal subjects.

CONCLUSION

This study demonstrates the overexpression of these two chemokine receptors in the conjunctival epithelium of patients treated for more than 1 year. Our results showing the simultaneous overexpression of CCR4 and CCR5 thus suggest that the chronic use of topical treatments may concurrently stimulate the TH1 and TH2 systems. These results evoke inflammatory mechanisms, combining allergy and toxicity, and confirm the complexity of inflammatory reactions occurring in the ocular surface of glaucoma patients.

Endophtalmie tardive compliquant la chirurgie filtrante du glaucome sans adjonction d’antimétabolites

PURPOSE

To identify the incidence, infecting organisms, and clinical results of late endophthalmitis after trabeculectomy without antifibrotic agents.

MATERIAL AND METHODS

The current retrospective study investigated 613 trabeculectomies without adjunctive antifibrotic agents performed between January 1994 and December 2003 in the Clinic of Ophthalmology of Beni-Messous University Hospital (Algiers, Algeria).

RESULTS

Eight eyes presented with late endophthalmitis after an uneventful postoperative period, for an incidence of 1.3%. The endophthalmitis occurred between 1 year and 7 years after the filtering surgery. Conjunctival swabs were taken in all cases. Vitreous swabs were taken in only six cases. There were five positive cases. The organisms identified were Staphylococcus aureus (one case), alpha hemolytic streptococci (two cases), Haemophilus sp. (one case), and Pseudomonas aeruginosa (pyocyanic) (one case). The anatomic and visual results were poor after treatment of endophthalmitis. One case deteriorated, ending in enucleation.

CONCLUSION

Late endophthalmitis may complicate glaucoma filtering surgery, several months or years later, after a postoperative period without incident. The surgical indications of glaucoma must take into account the complications related to this surgery.

Travoprost 0.004% With and Without Benzalkonium Chloride: A Comparison of Safety and Efficacy

PURPOSE

To compare the safety and efficacy of travoprost 0.004% without benzalkonium chloride (BAC) to that of the marketed formulation of travoprost 0.004% in patients with open-angle glaucoma or ocular hypertension.

METHODS

The study was a double-masked, randomized, parallel group, multicenter, noninferiority design. Adult patients with open-angle glaucoma or ocular hypertension with qualifying intraocular pressure (IOP) on 2 eligibility visits received either travoprost 0.004% with BAC (n=346), or travoprost 0.004% without BAC (n=344) dosed once-daily each evening. Patients were followed for a period of 3 months. IOP measurements at 8 AM, 10 AM, and 4 PM were taken at study visits on week 2, week 6, and month 3.

RESULTS

Mean IOP reductions, across all 9 study visits and times ranged from 7.3 to 8.5 mm Hg for travoprost 0.004% without BAC and from 7.4 to 8.4 mm Hg for travoprost 0.004% with BAC. Statistical equivalence was also demonstrated for the comparison of mean IOP changes; 95% confidence limits were within +/-0.8 mm Hg at 9 of 9 study visits and times in both the per protocol and intent-to-treat data sets. Adverse events and the number of patients discontinued owing to adverse events were similar for both treatment groups. Adverse events due to hyperemia occurred in 6.4% and 9.0% of patients treated with travoprost 0.004% without BAC and travoprost 0.004% with BAC, respectively.

CONCLUSION

Travoprost 0.004% without BAC is equivalent to travoprost 0.004% with BAC in both safety and efficacy.

Assessment of corneal epithelial integrity after acute exposure to ocular hypotensive agents preserved with and without benzalkonium chloride

The corneal toxicity of 2 intraocular pressure-lowering agents was compared in a rabbit cornea model with New Zealand White rabbits. Corneal epithelial morphology and cell size were assessed by in vivo confocal microscopy. Baseline microscopic examinations were performed on 1 eye of each animal. Two weeks later, the eyes were bathed for 3 min in travoprost 0.004% preserved without benzalkonium chloride (BAK( or latanoprost 0.005% preserved with 0.02% BAK; the eyes were then rinsed with balanced salt solution, and the corneas were again examined by confocal microscopy (n=4/group). A second group of animals was exposed to the medications through a dosing regimen of 1 drop/min (lpar3 drops total) (n=4/group). In eyes treated with travoprost without BAK (3-min bath), superficial epithelial cells were similar to baseline, as indicated by their visible cell borders and bright nuclei. In contrast, the surface cells in eyes treated with latanoprost were significantly smaller and brighter and had less distinct borders. Surface cell size was significantly smaller as compared with baseline size and as compared with rabbits treated with travoprost without BAK for 3 min. Similar effects on corneal epithelial cell morphology were observed with the 1-drop/min dosing regimen. In this rabbit model, travoprost 0.004% preserved without BAK did not cause corneal epithelial toxicity; latanoprost 0.005% induced superficial cell loss, most likely caused by the presence of a relatively high concentration of BAK (0.02%).

Measurement of inflammatory cytokines by multicytokine assay in tears of patients with glaucoma topically treated with chronic drugs

AIM

To investigate the ocular surface inflammatory response to chronic topical treatments in patients with glaucoma by measuring the cytokine level in tears using multiplex bead analysis.

METHODS

Tear samples were collected from 21 patients with glaucoma and 12 healthy volunteers. Tears were analysed for the presence of 17 cytokines: interleukin (IL)1beta, IL2, IL4, IL5, IL6, IL7, IL8, IL10, IL12, IL13, IL17, granulocyte-colony stimulating factor, granulocyte-macrophage stimulating factor, interferon (INF)gamma, monocyte chemotactic protein (MCP)1, macrophage inflammatory protein 1beta and tumour necrosis factor (TNF)alpha. The cytokines in each sample of tears were measured using multiplex bead analysis with microspheres as solid support for immunoassays.

RESULTS

In the tears of treated patients, proinflammatory cytokines (IL1beta, IL6, IL12, TNFalpha) were significantly increased compared with controls. T helper (Th)1 (INFgamma, IL2) and Th2 (IL5, IL10, IL4) type cytokines were also significantly higher (p<0.05); however, the most marked increase was observed with Th1 cytokines. The expression of chemokine IL8 and MCP1 was also increased in the treated group.

CONCLUSION

This study shows that pro-inflammatory cytokine secretion by conjunctival cells is increased in response to topical treatments for glaucoma. The characterisation of cytokines in tears was previously limited by the small volume attainable, a limitation that has been overcome by multiplex analysis.

Comparison of a non-preserved 0.1% T-Gel eye gel (single dose unit) with a preserved 0.1% T-Gel eye gel (multidose) in ocular hypertension and glaucomatous patients

AIM

This comparative, open design, phase III study was to assess the non-inferiority of the non-preserved T-Gel 0.1% single dose unit (SDU) versus its preserved multidose (MD) reference.

METHODS

175 patients with bilateral POAG or OHT were randomised: 87 patients were to receive one drop daily of T-Gel 0.1% MD and 88 patients were to receive one drop daily of T-Gel 0.1% SDU, for a treatment period of 12 weeks. The primary efficacy variable was the change in intraocular pressure (IOP) in the worse eye between the baseline and the last assessment. Subjective and objective ocular signs as well as adverse events were recorded for safety. Global tolerance was assessed by the investigator and by the patient.

RESULTS

The mean percentage reduction from baseline IOP was 24% for both treatments groups, which was consistent with previous studies. The safety results were comparable in both treatment groups. Because of gel formulation, mild short lasting episodes of blurred vision occurred for about 20% of patients. The global tolerance assessment reported that both treatments were well tolerated.

CONCLUSION

The overall study results demonstrated that T-Gel 0.1% SDU is not inferior to T-Gel 0.1% MD.

Deep sclerectomy for the treatment of exfoliation and primary open-angle glaucoma

PURPOSE

To retrospectively compare the efficacy of deep sclerectomy in the treatment of primary open-angle glaucoma (POAG) and exfoliation glaucoma (ExG).

METHODS

Deep sclerectomy with either collagen or hyaluronate implants was performed in 31 eyes (45%) with POAG and 38 eyes (55%) with ExG. Pre- and postoperative intraocular pressure (IOP) was recorded, as was the number of glaucoma medications used pre- and postoperatively in each group. The follow-up data referred to a mean period of 18 months (range: 2 weeks to 36 months).

RESULTS

At 18 months, complete success had been achieved in 56.3% of POAG eyes and 44.9% of ExG eyes. Qualified success had been achieved in 83.1% and 71.6% of POAG and ExG eyes, respectively. The mean IOP was 18.6 mmHg in POAG eyes and 16.3 mmHg in ExG eyes. YAG-descemetotomies were performed in nine eyes in each group. There were no statistically significant differences between the groups in IOP (except at 1 week postoperatively in favour of POAG; p = 0.05), success rates, need for postoperative glaucoma medication or number of complications. Reoperations were required in three (10%) POAG eyes and seven (18%) ExG eyes.

CONCLUSIONS

Deep sclerectomy is equally effective in controlling IOP in both POAG and ExG and has low rates of serious complications, even when the surgeon is inexperienced in the technique. Both survival rates and IOP control were similar between the groups, and there were no serious intra- or postoperative complications.

Allergic reaction to topical eyedrops

PURPOSE OF REVIEW

To examine recently published papers dealing with drug-induced allergic reactions. As allergy is only one possible mechanism, this review was extended to all reports or studies describing allergic, inflammatory or toxic effects related to eyedrops since 2004.

RECENT FINDINGS

These studies were first classified into clinical reports or surveys, experimental works and biological studies showing drug-induced effects on the ocular surface or eyelids. Studies aimed at determining the role of preservatives or comparing preservative-free and preserved eyedrops were further analysed separately.

SUMMARY

Reports on allergic or toxic reactions of eyedrops are published repeatedly. The reports raising the most important issues are those concerning antiglaucoma drugs. They consistently describe inflammatory reactions at the conjunctival level, with strong evidence that preservative is a major source of toxicity for the ocular surface.

Conjunctival epithelial cell expression of interleukins and inflammatory markers in glaucoma patients treated over the long term

PURPOSE

To compare the conjunctival epithelial cell expressions of inflammatory cytokines in normal subjects and in glaucoma patients treated over the long term.

DESIGN

Case-control study.

PARTICIPANTS

A total of 69 glaucoma patients treated over the long term and 15 normal subjects with no ocular abnormality or topical treatment.

METHODS

Amongst the 69 glaucoma patients, 27 were treated with preserved beta-blockers, 24 with unpreserved 0.5% timolol, and the other 18 patients with an association of > or =2 preserved drugs. All patients were treated for more than 1 year with the same treatment, with no significant differences between groups for mean ages and durations of treatment at the time of the study. Impression cytology specimens were taken and processed for immunofluorescence techniques. Conjunctival cell expressions of HLA DR, as a standard for inflammatory level, and the interleukins IL-6, IL-8, and IL-10 were obtained and quantified using flow cytometry.

MAIN OUTCOME MEASURES

Immune markers and proinflammatory cytokines in impression cytology specimens.

RESULTS

We found a significantly increased expression of all immunoinflammatory markers and mediators in the conjunctival epithelium of glaucoma patients compared with normal eyes. Human leukocyte antigen DR was significantly higher in the 2 groups receiving preserved drugs than in the unpreserved timolol group. The 3 interleukins were similarly overexpressed in all glaucoma groups, with no significant between-groups differences except for the expression level of IL-8, which was significantly higher in the multitreatment group than in the preservative-free one.

CONCLUSIONS

The present study confirms the increased expression of immunoinflammatory markers by the conjunctival epithelium of glaucoma patients treated over the long term. The development of nontoxic preservatives or preservative-free solutions is therefore of great interest.

Antifibrotics and wound healing in glaucoma surgery

When medical and laser therapy fail to control intraocular pressure, glaucoma filtration surgery needs to be performed. Glaucoma surgery is unique in that its success is linked to interruption of the wound-healing response in order to maintain patency of the new filtration pathway. In this article we will review the wound-healing pathway and the pharmacologic interventions that have been employed clinically and experimentally to interrupt wound healing, particularly steroids and the antifibrotic agents 5-fluorouracil and mitomycin C. A review of the published literature looking at use of these agents to enhance success as well as the associated complications are presented, critiqued, and interpreted in order to put the studies in proper perspective. Future directions and recommendations regarding use of these agents are available and an introduction to newer wound modulating agents such as anti-transforming growth factor beta 2 is presented.

Ocular tolerance of preservatives and alternatives

Eye drops are multiple dosage forms protected against microbial contamination by means of preservatives. However, the ocular tolerance of these chemicals can vary and this may result in adverse toxic or allergic reactions. This overview presents the pharmacopoeial requirements for the preservation of eye drops, the factors affecting ocular tolerance as well as the adverse external ocular effects induced by preservatives. The alternatives to the use of preservatives are also discussed, including the recent progress in eye drops packaging.

Prevalence of ocular symptoms and signs with preserved and preservative free glaucoma medication

AIM

To determine the incidence of ocular toxicity of preservatives with glaucoma medications.

METHODS

A prospective epidemiological survey was carried out in 1999 by 249 ophthalmologists on 4107 patients. Ocular symptoms, conjunctiva, cornea, and eyelids were assessed. A chi(2) test was used for differences between preserved eye drops (P) and preservative free eye drops (PF).

RESULTS

84% patients used P, 13% received PF, and 3% a combination of P and PF eye drops. All symptoms were more prevalent with P than with PF drops (p<0.001): discomfort upon instillation (43% versus 17%), and symptoms between instillations such as burning-stinging (40% versus 22%), foreign body sensation (31% versus 14%), dry eye sensation (23% versus 14%), tearing (21% versus 14%), and eyelid itching (18% versus 10%). An increased incidence (>2 times) of ocular signs was seen with P eye drops. The prevalence of signs and symptoms was dose dependent, increasing with the number of P drops. A reduction in the symptoms and signs was observed when patients changed from P to PF eye drops (p<0.001).

CONCLUSIONS

Symptoms and signs are less prevalent when PF drops are used. Moreover, most of the adverse reactions induced by P glaucoma medication are reversible after removing preservatives.

Cicatricial entropion associated with chronic dipivefrin application

PURPOSE

To report patients who presented to the oculoplastics department for repair of cicatrical entropion after topical use of dipivefrin. To discuss the possible mechanisms of action and highlight the potential detrimental effects of dipivefrin on palpebral conjunctiva.

METHODS

Retrospective consecutive noncomparative case series. Nine eyes from 6 patients, 74 years to 90 years of age, referred by ophthalmologists for repair of cicatricial entropion after at least 2 years of twice-a-day application of dipivefrin.

RESULTS

After cessation of topical dipivefrin application and successful surgical repair of entropion, no recurrence of signs or symptoms has been reported. Moderate lymphocytic infiltration of the substantia propria of the conjunctiva of both upper and lower lid specimens was present, as was scarring and keratinization of the epithelium.

CONCLUSIONS

Cicatrization in the substantia propria of the conjunctiva by excessive lymphocytic infiltration after topically administered antiglaucoma drugs including dipivefrin is a possible mechanism of action for entropion.

The use of the G1 and Octosmart programs in detecting temporal changes in the visual field

PURPOSE

The Octopus program Octosmart is able to classify visual fields into six classes. In the program a horizontal bar indicates these classes, and an indicator points to the most probable position, related to the measured pathology. The width of this dashed indicator shows the range of possible fluctuations in the measurement and, therefore, its precision. This study sets out to analyse the suitability of this display mode using other visual-field index data.

METHODS

The visual fields of 83 glaucomatous eyes of 61 patients of various etiological groups and glaucoma suspects were studied for periods varying from 1 to 5 years in a retrospective study. All examinations were performed with the G1 Octopus program and analyzed with the Octosmart program. The statistical significance of linear trends of the visual-field indices, mean defect (MD) and corrected loss variance (CLV), and the class shown by the indicator (POI = position of indicator) were determined, and their regression coefficients were analyzed by means of a linear trend test as a function of time.

RESULTS

Of the sample of 83 tested eyes, a total of 18 significant trends were recorded after five examinations. All visual-field indices showed a trend towards amelioration.

CONCLUSIONS

The 18 significant trends observed must be attributed to perturbing long-term fluctuations and, despite their statistical significance, are of little clinical value. It is questionable whether an increased number of examinations per eye would have attenuated the threshold fluctuations sufficiently to make the change in field class more reliable.

Differences in ocular surface irritation between timolol hemihydrate and timolol maleate

PURPOSE

We evaluated the anterior segment surface reaction findings between timolol hemihydrate and timolol maleate. The only known difference between these preparations is the maleate salt.

METHODS

After a baseline examination, we randomized 28 healthy subjects (26 completed) to timolol hemihydrate or timolol maleate given in both eyes twice daily, in a double masked fashion, for 1 week. Subjects then were evaluated at the morning trough (hour 0 examination), dosed, and re-evaluated in 1 hour (hour 1 examination). Subjects were left untreated for 1 week and then switched to the opposite medication for the second study period.

RESULTS

Corneal staining (graded 0 to 4) for timolol maleate was worse between baseline (0.9) and hour 0 (1.4; P =.009) and baseline and hour 1 (1.4; P =.011). Also, mean punctate corneal staining for timolol maleate was increased from baseline (22.6) to hour 0 (31.7; P =.033) and showed borderline significance to hour 1 (33.4; P =.058), and for timolol hemihydrate there was a borderline significant elevation from baseline (24.2) to hour 1 (29.8; P =.060). When treatment groups were compared, there was a greater change in corneal staining with timolol maleate than timolol hemihydrate from baseline to hour 0 (P =.020) and greater staining with timolol maleate than timolol hemihydrate at hour 0 (P =.032). Nasal conjunctiva showed increased mean staining with timolol maleate from baseline (23.6, P =.035) to hour 0 (29.5, P =.035) and to hour 1 (31.9 P =.038) but not with timolol hemihydrate. There were increased symptoms of ocular dryness from baseline to hour 0 with timolol maleate (P =.012) but not with timolol hemihydrate.

CONCLUSIONS

The study suggests that timolol maleate potentially may have more of an irritant effect than timolol hemihydrate on the corneal and nasal conjunctival epithelium.

The National Survey of Trabeculectomy. I. Sample and methods

PURPOSE

The National Survey of Trabeculectomy was designed to evaluate current practices of glaucoma surgery in the United Kingdom and to determine the success and complication rates of trabeculectomy on a national basis. This paper reports the survey methods, levels of consultant activity, waiting times, indications for surgery and the demographic and clinical characteristics of the patient sample.

METHODS

Consultant ophthalmologists performing trabeculectomy in the United Kingdom were studied. Four consecutive patients undergoing trabeculectomy under each consultant prior to 18 June 1996 were retrospectively sampled. Patients were followed prospectively and evaluated 6 and 12 months after surgery. Data were collected by self-administered postal questionnaires. To determine the effects of selection and reporting bias a validation study of 14 randomly selected units was also conducted.

RESULTS

Three hundred and eighty-two consultants recruited 1454 eligible patients for analysis. The mean age of patients was 69.2 years (standard deviation 10.9) and 51.7% were male. The underlying diagnosis was primary open angle glaucoma in 89.2%, pseudoexfoliation glaucoma in 5.4%, normal tension glaucoma in 3.8% and pigmentary glaucoma in 1.6%. There was advanced visual field damage in 50.5% of the cohort by the time of listing. The main indications for surgery were failure of medication to control intraocular pressure in 57.1%, progressive visual field loss in 26.5% and progressive optic disc damage in 4.8%. Primary surgery was undertaken in 4.8% of patients. In 80% trabeculectomy was performed within 3 months of listing. However, almost a third of consultants considered individual patient's waiting time too long. Validation studies confirmed that systematic bias did not operate in the selection of patients for the survey or in the reporting of outcomes.

CONCLUSION

The findings of this survey are representative of current practices of trabeculectomy by consultants throughout the United Kingdom and show considerable variation in practice. Failure to control intraocular pressure with topical medications was the main indication for surgery. Advanced glaucomatous visual field damage was present at the time of surgery in half the sample. Though most patients were operated on within 3 months of listing, almost a third of consultants considered the wait unacceptably long.

Adverse effects of topical antiglaucomatous medications on the conjunctiva and the lachrymal (Brit. Engl) response

BACKGROUND

Increasing evidence indicates that long-term use of topically administered medication can induce changes in the conjunctiva and lachrymal function.

METHODS

In order to evaluate changes in the conjunctiva and lachrymal response after prolonged use of topically administered antiglaucoma medications and preservatives found in antiglaucomatous medication solutions (benzalkonium chloride), we tested lachrymal function (Schirmer I., Jones, BUT, Ferning tests) and used the conjunctival impression cytology technique.

MATERIALS

A group of patients with primary open angle glaucoma (POAG) receiving topical antiglaucomatous medication were recruited. A second group received only preservative instillations while a control group was formed of similarly aged subjects with no eye disease and was given topical or systemic medical therapy. Excluded from the trial were patients with a history of external eye disease or who had received conjunctival surgery.

RESULTS

Tear secretion was reduced against that of the control group in those subjects who received protracted administration of antiglaucomatous eyedrops (timolol and/or pilocarpine). A statistically significant degree of conjunctival metaplasia was associated with long-term use of topical medication. The subjective symptoms reported by those patients receiving chronic topical antiglaucomatous therapy and the objective observations on them were found to be proportional to the observed tearing response. Changes were more pronounced in subjects who received only benzalkonium chloride.

CONCLUSION

Our study results suggest that long-term use of antiglaucoma medication induces changes in both tear film and conjunctival surface. Such changes may be related to the medication or the duration of treatment, but may also be due to the preservatives used in the commercial product.

Ocular surface inflammatory changes induced by topical antiglaucoma drugs: human and animal studies

OBJECTIVES

To investigate conjunctival and trabecular specimens from patients with glaucoma according to the duration and number of drugs received before filtration surgery, and to confirm, in a complementary experimental model, the role of preservative by comparing the effects of preserved and nonpreserved timolol.

STUDY DESIGN

Experimental animal and human tissue study.

PARTICIPANTS

Paired specimens of conjunctiva and trabeculum were taken from 61 patients undergoing trabeculectomy. Twenty-six patients were treated with 2 or more drugs for at least 1 year; 30 had received a beta-blocker for more than 1 year and 5 underwent primary surgery. A second study was performed in 25 rats receiving topical solutions in both eyes for 1 month.

INTERVENTION

Immunohistochemistry was performed in all biopsy specimens using 12 different monoclonal antibodies. Ocular structures from rats treated for 1 month with preserved 0.5% timolol, nonpreserved 0.5% timolol, or 0.01% benzalkonium chloride were similarly investigated in an experimental study.

MAIN OUTCOME MEASURES

Inflammatory cell infiltrates and fibroblasts were evaluated in biopsies, as well as in animal specimens, together with histologic changes induced by the drugs applied.

RESULTS

Twenty-four of 26 conjunctivae and 21 of 24 trabecular pieces from multitreated patients were found to be abnormally infiltrated by cells expressing inflammatory or fibroblastic markers or both. Nineteen of 30 conjunctivae and 9 of 22 trabeculums in the monotherapy group and only 1 of 5 specimens from the primary surgery group were abnormal. In rats, preserved timolol and benzalkonium similarly showed infiltrates together with toxic histopathologic changes as compared to the nonpreserved timolol and control groups.

CONCLUSIONS

These two combined studies confirmed histopathologic effects of antiglaucomatous drugs on the conjunctiva and showed similar effects in the trabecular meshwork. The experimental study showed that benzalkonium chloride is at least, to a large part, responsible for these toxic or immunoinflammatory effects or both on the ocular structures.

Trabeculectomy augmented with mitomycin C application under the scleral flap

AIM

The authors investigated the safety and intraocular pressure (IOP) lowering effectiveness of trabeculectomy augmented with mitomycin C application beneath the scleral flap, and assessed the influence of preoperative risk factors on the surgical outcome.

METHODS

A retrospective study of 72 consecutive high risk eyes undergoing trabeculectomy with adjunctive mitomycin C (0.2 mg/ml) applied under the scleral flap for 5 minutes was performed. Each eye was ascribed a score based on the number of preoperative risk factors, and categorised into one of three risk factor groups. Success was described as unqualified where IOP was < or = 21 mm Hg without medication and qualified where antiglaucomatous therapy was required to maintain it at such a level. A life table analysis of IOP control was calculated.

RESULTS

The mean IOP (SD) fell from a preoperative level of 28.4 (6.9) to a level of 16.63 (8.06) mm Hg at the last follow up (paired Student's t test: p < 0.0001). Fifty two eyes (72%) were classed as unqualified successes. The survival rates did not differ significantly between different risk factor groups (log rank test: chi 2 = 0.967, p > 0.1). The incidence of postoperative complications compared favourably with reports of mitomycin C application between Tenon's capsule and the undissected scleral bed.

CONCLUSION

The results illustrate that mitomycin C applied beneath the scleral flap during trabeculectomy in high risk eyes is associated with a success rate comparable to other modes of application. The incidence of potentially serious complications such as conjunctival wound leak and prolonged hypotony was lower than previously published data reporting sub-Tenon's administration of mitomycin C. The number and nature of preoperative risk factors do not appear to influence the surgical outcome. A possible mechanism of action is proposed.

CA 19-9 ELISA test: a new method for studying mucus changes in tears

AIMS

This study investigated mucus changes in the tears in various eye conditions using impression cytology. The quantity of mucins was measured by enzyme linked immunosorbent assay (ELISA) using the tumour marker CA 19-9. This assay quantifies the sialylated Lewis(a) structure mainly associated with ocular mucins.

METHODS

Impression cytology was performed using a cellulose nitrate membrane, on 53 healthy patients, 50 glaucoma patients treated with beta blockers, 24 patients suffering from dry eye syndrome, and 45 contact lens wearers. The tear film glycoproteins were eluted and CA 19-9 was measured.

RESULTS

CA 19-9 content expressed as kilo units (kU) per microgram of tears was significantly decreased in dry eye syndrome (25.8 kU (SD 17.3)/microgram) (p < 0.05), glaucoma patients over 60 years (28.9 (19.5) kU/microgram) (p < 0.05), and contact lens wearers (28.4 kU (18)/microgram) (p < 0.05), when compared with healthy individuals (39.4 kU (22.2)/microgram).

CONCLUSION

Impression cytology can be regarded as a valuable method for obtaining samples of glycoconjugates of mucin. The decrease of sialylated chains observed with this method confirms the hypothesis that some quantitative changes in the tear film may be encountered in ocular surface disorders.

Early conjunctival changes following treatment with metipranolol and preservatives are not reversible with dexamethasone

BACKGROUND

Topical medication for the treatment of glaucoma alters the cellular and extracellular composition of the superficial and deep conjunctival layers. We sought to determine whether, after short-term use of metipranolol with preservatives, subsequent application of steroids or metipranolol without preservatives affects these conjunctival changes.

METHODS

Rabbits received topical metipranolol over a period of 6 months. For the following 2 months, one group received metipranolol without preservatives, and another group steroids. For controls, animals were treated with preservatives only or metipranolol with preservatives for 6 months. Superior bulbar conjunctiva was examined by light microscopy, immunohistochemistry, and transmission electron microscopy.

RESULTS

On light microscopic and immunohistochemical examination of conjunctival specimens from all groups, there was an increase of subepithelial collagen deposition in all treated groups. Treatment with steroids or preservative-free metipranolol did not alter the initial effects. By electron microscopy, additional extracellular matrix changes were seen as well as degenerative changes of tissue fibroblasts.

CONCLUSION

The animal model used was able reliably to produce conjunctival changes following antiglaucomatous therapy. The changes seen were early changes, because there was no increase of inflammatory cells. Steroids did not significantly affect the changes. The beneficial effect of steroids used prior to glaucoma surgery remains controversial.

Conjunctiva and subconjunctival tissue in primary open-angle glaucoma after long-term topical treatment: an immunohistochemical and ultrastructural study

BACKGROUND

Primary open-angle glaucoma is commonly treated with long-term hypotensive medical therapy. When this approach becomes inadequate, therapy proceeds with surgery. The present study investigates morphological changes in the conjunctival and subconjunctival tissues induced by short- and long-term topical medical therapy of primary open-angle glaucoma.

METHODS

Comparisons were made between biopsy specimens from glaucomatous patients, who received specific eyedrop therapy (timolol and pilocarpine) for various periods of time, and control patients with no conjunctival pathology or topical treatment. Histological, immunohistochemical and ultrastructural parameters were investigated.

RESULTS

The morphometric analysis of histological sections and immunohistochemistry (anti-fibronectin antibody) in medium- and long-term therapy patients showed: (a) significant increases in the thickness and number of epithelial cell layers; (b) significant increases in the fibroblast density in both subepithelial and deep connective tissue; and (c) a more compact connective tissue, richer in collagen fibers arranged in whirls, with some inflammatory elements. These findings were confirmed by the ultrastructural analysis. In the same patients, the other immunohistochemical parameters investigated (anti-HLA-DR, anti-CD1a, anti-CD4, anti-CD8, anti-IL2 and C3b antibodies) revealed a tendency to chronic inflammation. Following specific surgery, this tendency manifested itself in a diffuse immune response, especially in those patients who underwent medium- and long-term medical therapy.

CONCLUSION

According to these results, antiglaucomatous surgery should be rehabilitated and considered as an alternative to long-term medical therapy in the first-instance treatment of primary open-angle glaucoma.

The effect of preservatives and antiglaucomatous medication on the histopathology of the conjunctiva

BACKGROUND

Topical medication applied chronically for the treatment of glaucoma changes the cellular profile of the conjunctiva. We wanted to determine the role of preservatives, which are usually combined with the drugs, on this effect.

METHODS

We applied metipranolol 0.3% and pilocarpine 2% with and without benzalkonium chloride 0.01% and cetrimonium chloride 0.004%, respectively. Twenty-four rabbits, divided into four groups, were treated for 3 months. The complete globes and the adherent bulbar conjunctiva were examined histopathologically and immunohistochemically.

RESULTS

With special stains for collagen, a slight increase of the thickness of subepithelial collagen of the conjunctiva was present in both groups treated with medication and preservative compared with eyes treated with medication alone. This effect was also true for special antibodies for collagen type IV and alpha-smooth muscle actin in the eyes treated with pilocarpine, but not in the eyes treated with metipranolol.

CONCLUSION

The results suggest that preservatives may have an additional adverse effect on the conjunctiva in addition to the effects of the medications alone.

Vascular changes over trabeculectomy blebs

Low-dose anterior segment fluorescein angiography was performed on 10 eyes before and after trabeculectomy with a limbal-based conjunctival flap. Post-trabeculectomy angiography shows that all successful trabeculectomies have an area of decreased capillary vascular perfusion over the bleb site not coincidental with the area of the bleb and that there is delayed filling of vessels running over the bleb.