Gene therapies and gene product-based drug candidates for normalizing and preserving tissue functions in animal models of ocular hypertension and glaucoma

More than 76 million people worldwide are afflicted with the neurodegenerative eye diseases described and grouped together as glaucoma. A common feature amongst the many forms of glaucoma is chronically elevated intraocular pressure (IOP) within the anterior chamber of the eye that physically damages the retina, optic nerve and parts of the brain connected with visual perception. The mediators of the contusing raised IOP responsible for such damage and loss of vision include locally released inflammatory agents, tissue remodeling enzymes and infiltrating immune cells which damage the retinal ganglion cell (RGC) axons and eventually kill a significant number of the RGCs. Additional culprits include genetic defects of the patient that involve aberrations in receptors, enzymes and/or endogenous ligands and possible over- or under-production of the latter. Other genetic abnormalities may include issues with signal transduction machinery within key cells of critical tissues in the front (e.g. trabecular meshwork [TM] and Schlemm's canal [SC]) and back of the eye (e.g. retinal ganglion cells and their axons). Genome-wide associated studies (GWAS) coupled with next generation sequencing have provided powerful linkage of certain gene defects and polymorphic variants to the onset and progression of diseases of the tissues involved in fluid dynamics in the TM and SC, and many retinal elements (lamina cribosa, optic nerve head) at the back of the eye which cause ocular hypertension (OHT) and glaucomatous optic neuropathy (GON), respectively. Despite the availability of some drugs, fluid drainage microshunts and full surgical techniques to lower and control intraocular pressure, the major modifiable biomarker of open-angle and other forms of glaucoma, their side-effect profiles, less than optimum effectiveness and short duration of action present opportunities to clinically manage the glaucomas with next generation of treatments with high therapeutic indices, including gene therapies. Thus, identification, characterization and deployment of genetic data coupled with traditional drug discovery and novel gene replacement, gene editing and genetic engineering technologies may provide some solutions to the aforementioned problems. These aspects will be discussed in this article.

Treatment expectations in glaucoma: what matters most to patients?

BACKGROUND/OBJECTIVES

Recent clinical trials in glaucoma have used patient-reported outcome measures (PROMs) of health-related quality of life to evaluate interventions. However, existing PROMs may not be sufficiently sensitive to capture changes in health status. This study aims to determine what really matters to patients by directly exploring their treatment expectations and preferences.

SUBJECTS/METHODS

We conducted a qualitative study using one-to-one semi-structured interviews to elicit patients' preferences. Participants were recruited from two NHS clinics serving urban, suburban and rural populations in the UK. To be relevant across glaucoma patients under NHS care, participants were sampled to include a full range of demographic profiles, disease severities and treatment histories. Interview transcripts were evaluated using thematic analysis until no new themes emerged (saturation). Saturation was established when 25 participants with ocular hypertension, mild, moderate and advanced glaucoma had been interviewed.

RESULTS

Themes identified were: Patients' experiences of living with glaucoma, patients' experiences of having glaucoma treatment, most important outcomes to patients, and COVID-related concerns. Participants specifically expressed their most important concerns, which were (i) disease-related outcomes (intraocular pressure control, maintaining vision, and being independent); and (ii) treatment-related outcomes (treatment that does not change, drop-freedom, and one-time treatment). Both disease-related and treatment-related experiences were covered prominently in interviews with patients across the spectrum of glaucoma severity.

CONCLUSIONS

Outcomes related both to the disease and its treatment are important to patients with different severities of glaucoma. To accurately evaluate quality of life in glaucoma, PROMs may need to assess both disease-related and treatment-related outcomes.

Negative Pressure Application via a Multi-Pressure Dial to Lower IOP in Patients with Suspected Glaucoma or Open Angle Glaucoma

PRCIS

The multi-pressure dial applies localized periocular negative pressure to safely and effectively lower IOP and represents the first non-invasive, non-pharmacologic device for IOP reduction.

OBJECTIVE

To evaluate the safety and effectiveness of the Multi-Pressure Dial (MPD) system, a device that applies periocular negative pressure to lower intraocular pressure (IOP).

SETTING

6 investigational sites, United States.

DESIGN

Prospective, assessor-masked, randomized controlled trial.

METHODS

Subjects with suspected glaucoma, ocular hypertension (OHTN), and open angle glaucoma (OAG) with baseline IOP ≥13 mmHg and ≤32 mmHg were enrolled. One eye of each subject was randomized to receive negative pressure application; the fellow eye served as a control. The study eye negative pressure setting was programmed for 60% of the baseline IOP. The primary effectiveness endpoint was the proportion of study eyes versus control eyes achieving an IOP reduction ≥20% at Day 90. Secondary endpoints included the proportion of eyes achieving an IOP reduction ≥25% at Day 90 as well as the proportion of eyes achieving an IOP reduction ≥20% at Days 30 and 60.

RESULTS

116 eyes of 58 subjects completed the study. At the Day 90 visit, 89.7% ( n =52) of study eyes versus 3.4% ( n =2) of control eyes achieved an IOP reduction ≥20% ( P <0.001). At Day 90, 77.6% ( n =45) of study eyes achieved a ≥25% IOP reduction compared to 1.7% ( n =1) of control eyes ( P <0.001). The most commonly reported adverse events were lid (17.2% study eye, 7.8% control eye) and periorbital edema (14.1% study eye, 10.9% control eye).

CONCLUSIONS

This trial demonstrates that the MPD safely and effectively lowers IOP in a group of patients that included glaucoma suspects, OHTN, and patients with OAG.

Cell-Specific Expression of Human SIRT1 by Gene Therapy Reduces Retinal Ganglion Cell Loss Induced by Elevated Intraocular Pressure

SIRT1 prevents retinal ganglion cell (RGC) loss in several acute and subacute optic neuropathy models following pharmacologic activation or genetic overexpression. We hypothesized that adeno-associated virus (AAV)-mediated overexpression of SIRT1 in RGCs in a chronic ocular hypertension model can reduce RGC loss, thereby preserving visual function by sustained therapeutic effect. A control vector AAV-eGFP and therapeutic vector AAV-SIRT1 were constructed and optimized for transduction efficiency. A magnetic microbead mouse model of ocular hypertension was optimized to induce a time-dependent and chronic loss of visual function and RGC degeneration. Mice received intravitreal injection of control or therapeutic AAV in which a codon-optimized human SIRT1 expression is driven by a RGC selective promoter. Intraocular pressure (IOP) was measured, and visual function was examined by optokinetic response (OKR) weekly for 49 days following microbead injection. Visual function, RGC survival, and axon numbers were compared among control and therapeutic AAV-treated animals. AAV-eGFP and AAV-SIRT1 showed transduction efficiency of ~ 40%. AAV-SIRT1 maintains the transduction of SIRT1 over time and is selectively expressed in RGCs. Intravitreal injections of AAV-SIRT1 in a glaucoma model preserved visual function, increased RGC survival, and reduced axonal degeneration compared with the control construct. Over-expression of SIRT1 through AAV-mediated gene transduction indicates a RGC-selective component of neuroprotection in multiple models of acute optic nerve degeneration. Results here show a neuroprotective effect of RGC-selective gene therapy in a chronic glaucoma model characterized by sustained elevation of IOP and subsequent RGC loss. Results suggest that this strategy may be an effective therapeutic approach for treating glaucoma, and warrants evaluation for the treatment of other chronic neurodegenerative diseases.

Optic Disc Drusen in Patients With Ocular Hypertension: A Case Series and Review of the Literature

BACKGROUND

The identification of glaucomatous optic neuropathy in the setting of optic disc drusen (ODD) is a challenge, and the decision of whether to offer treatment in the form of intraocular pressure (IOP) reduction is controversial. Here, we present a series of patients with coexisting ocular hypertension and ODD to evaluate clinical features, treatment options, and progression of optic neuropathy. In addition, a review of the literature on ODD with elevated IOP is provided.

METHODS

Six patients with ODD and a history of ocular hypertension are presented. Components of the examination and imaging modalities used to establish the diagnosis of ODD were recorded and a description of ocular hypertension history, glaucoma testing, and the potential treatment of IOP were also provided.

RESULTS

In this series, 4 of 6 patients with concurrent ocular hypertension and ODD showed progression of optic neuropathy as assessed by visual field or retinal nerve fiber layer thickness. Of the 2 patients who did not show evidence of progression, 1 was treated with IOP-lowering medications and 1 was observed off treatment. Of the 4 patients who showed evidence of progression, all 4 were initially treated with IOP-lowering medications and 2 ultimately went on to have trabeculectomy surgery. In the patients with progressive optic neuropathy, lowering the IOP seemed to halt the progression suggesting there was a pressure-sensitive component.

CONCLUSIONS

Distinguishing changes to the optic nerve, particularly the structural changes at the lamina cribrosa of true glaucomatous optic neuropathy in the setting of ODD, is a challenge. Careful consideration of risk factors including age, presenting features, progression indicators, and management goals is to be accounted for in the decision to offer treatment. We see the presence ODD in the patients with ocular hypertension as an additional risk for progressive changes to the nerve fiber layer and visual field that needs to be considered when determining whether to initiate therapy. Our data suggest that treatment of IOP in the patients with ocular hypertension with ODD and evidence of progression reduces the risk of further progression. Further work is needed to determine whether progression of optic neuropathy in the setting of coexisting ODD and ocular hypertension is related mechanistically to predominantly an ODD-type process, a glaucomatous process, or a combination thereof.

Effect of high-intensity focused ultrasound (HiFU) treatment on intraocular pressure and aqueous humour dynamics: 12 -months results

PURPOSE

High intensity focused ultrasound (HiFU) is a cyclodestructive therapy for controlling intraocular pressure (IOP) in glaucoma. The mechanism of action is thought to be through destruction of the ciliary epithelium as well as increased uveoscleral outflow. We reviewed the change in aqueous humour dynamics parameters including aqueous humour flow rate, tonographic outflow facility (TOF) and uveoscleral outflow at 12 months.

PATIENTS AND METHODS

This is a prospective observational study. Consecutive patients with open angle glaucoma (OAG) or ocular hypertension (OHT) requiring further IOP lowering were enroled in the study between August 2016 and January 2017. Patients were commenced on medication washout period prior to baseline and twelve months' visit.

RESULTS

Sixteen patients (OAG) in the treatment group underwent assessment at twelve months follow up. Mean age was 63.1 ± 11 years. Eleven patients were African/Caribbean and 5 were Caucasian. Nine patients were female and 7 were male. Mean post-washout IOP was reduced by 21% (28.3 ± 5.7 at baseline vs 22.4 ± 8.4 mmHg at 12 months, p = 0.04). Aqueous humour flow rate was reduced by 16% at twelve months (2.40 ± 0.6 at baseline vs 2.02 ± 0.6 µl/min at 12 months, p = 0.0493). There was no statistically significant change in the TOF (0.12 ± 0.09 at baseline vs 0.08 ± 0.05 µl/min/mmHg at 12 months, p = 0.08) or uveoscleral outflow (0.6 ± 1.3 at baseline vs 1.3 ± 0.85 µl/min at 12 months, p = 0.15).

CONCLUSION

In this study, we demonstrated that the observed IOP reduction was likely due to aqueous humour flow rate reduction. The TOF and uveoscleral outflow were not detectibly changed.

[Whether lowering intraocular pressure is needed for thyroid associated ophthalmopathy with intraocular hypertension]

Patients with thyroid associated ophthalmopathy often have elevated intraocular pressure. Patients and doctors are often confused about whether intraocular hypertension in thyroid associated ophthalmopathy needs to be lowered. There are several theories on the possible causes of this kind of increased intraocular pressure: restriction and compression of the globe by fibrotic and enlarged rectus muscles, increased episcleral venous pressure resulting from orbital congestion and venous outflow obstruction, and increased resistance to trabecular outflow. In addition, the patient's eye position and the device for measuring intraocular pressure also have great impacts on the accuracy of intraocular pressure measurement. At the same time, there are very few patients with thyroid associated ophthalmopathy combined with primary glaucoma. Therefore, whether patients with elevated intraocular pressure need to be treated depends on the specific clinical manifestations of the thyroid associated ophthalmopathy. Intraocular pressure of most patients can be lowered by active treatment for thyroid associated ophthalmopathy; antiglaucoma medical therapy may be necessary for patients whose intraocular pressure cannot be lowered; only very few cases of glaucoma require antiglaucoma drugs or surgery. (Chin J Ophthalmol, 2019, 55:811-813).

Selective laser trabeculoplasty versus eye drops for first-line treatment of ocular hypertension and glaucoma (LiGHT): a multicentre randomised controlled trial

BACKGROUND

Primary open angle glaucoma and ocular hypertension are habitually treated with eye drops that lower intraocular pressure. Selective laser trabeculoplasty is a safe alternative but is rarely used as first-line treatment. We compared the two.

METHODS

In this observer-masked, randomised controlled trial treatment-naive patients with open angle glaucoma or ocular hypertension and no ocular comorbidities were recruited between 2012 and 2014 at six UK hospitals. They were randomly allocated (web-based randomisation) to initial selective laser trabeculoplasty or to eye drops. An objective target intraocular pressure was set according to glaucoma severity. The primary outcome was health-related quality of life (HRQoL) at 3 years (assessed by EQ-5D). Secondary outcomes were cost and cost-effectiveness, disease-specific HRQoL, clinical effectiveness, and safety. Analysis was by intention to treat. This study is registered at controlled-trials.com (ISRCTN32038223).

FINDINGS

Of 718 patients enrolled, 356 were randomised to the selective laser trabeculoplasty and 362 to the eye drops group. 652 (91%) returned the primary outcome questionnaire at 36 months. Average EQ-5D score was 0·89 (SD 0·18) in the selective laser trabeculoplasty group versus 0·90 (SD 0·16) in the eye drops group, with no significant difference (difference 0·01, 95% CI -0·01 to 0·03; p=0·23). At 36 months, 74·2% (95% CI 69·3-78·6) of patients in the selective laser trabeculoplasty group required no drops to maintain intraocular pressure at target. Eyes of patients in the selective laser trabeculoplasty group were within target intracoluar pressure at more visits (93·0%) than in the eye drops group (91·3%), with glaucoma surgery to lower intraocular pressure required in none versus 11 patients. Over 36 months, from an ophthalmology cost perspective, there was a 97% probability of selective laser trabeculoplasty as first treatment being more cost-effective than eye drops first at a willingness to pay of £20 000 per quality-adjusted life-year gained.

INTERPRETATION

Selective laser trabeculoplasty should be offered as a first-line treatment for open angle glaucoma and ocular hypertension, supporting a change in clinical practice.

FUNDING

National Institute for Health Research, Health and Technology Assessment Programme.

Ab interno trabecular bypass surgery with iStent for open-angle glaucoma

BACKGROUND

Glaucoma is a leading cause of irreversible blindness worldwide. In early stages, glaucoma results in progressive loss of peripheral (side) vision; in later stages, it results in loss of central vision leading to blindness. Elevated intraocular pressure (IOP) is the only known modifiable risk factor for glaucoma. Minimally invasive glaucoma surgical (MIGS) techniques, such as ab interno trabecular bypass surgery with iStent (Glaukos Corporation, Laguna Hills, CA, USA), have been introduced as a new treatment modality for glaucoma. However, the effectiveness of MIGS on keeping people 'drop-free' (i.e. not having to use eye drops to control IOP) and other outcomes is uncertain.

OBJECTIVES

To assess the effectiveness and safety of ab interno trabecular bypass surgery with iStent (or iStent inject) for open-angle glaucoma in comparison to conventional medical, laser, or surgical treatment.

SEARCH METHODS

Cochrane Eyes and Vision's Information Specialist searched the following databases on 17 August 2018: the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register; 2018, Issue 7), MEDLINE Ovid, Embase Ovid, the ISRCTN registry, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We applied no date or language restrictions. We searched the reference lists of reports from included studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that had compared iStent or iStent inject to medical therapy, laser treatment, conventional glaucoma surgery (trabeculectomy), or other MIGS procedures. We included RCTs that had compared iStent or iStent inject in combination with phacoemulsification to phacoemulsification alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently screened search results, assessed risk of bias, and extracted data from reports of included RCTs using an electronic data collection form.

MAIN RESULTS

We included seven RCTs (765 eyes of 764 participants; range per study 33 to 239 participants) that evaluated iStent in people with open-angle glaucoma. We also identified 13 studies that are ongoing or awaiting publications of results. Most participants in the included studies were women (417/764 (55%) participants) and older age (age range: 49 to 89 years). We assessed most trials at unclear or high risk of bias: four trials did not clearly report the method of generating the random sequence or concealing allocation; five were unmasked, open-label studies, which we assessed at high risk of bias for performance and detection bias. All seven trials were funded by the Glaukos Corporation. We graded the certainty of evidence as very low.Four RCTs compared iStent in combination with phacoemulsification to phacoemulsification alone. The summary estimate which we derived from two of the four RCTs suggested that participants in the iStent in combination with phacoemulsification group were 1.38 times more likely to be drop-free between six and 18 months than those in the phacoemulsification alone group (risk ratio (RR) 1.38, 95% confidence interval (CI) 1.18 to 1.63, I² = 67%). Data from two RCTs also suggested that iStent in combination with phacoemulsification compared to phacoemulsification alone may have offered a small reduction in number of IOP-lowering drops (mean difference (MD) -0.42 drops, 95% CI -0.60 to -0.23). It is uncertain whether there was any difference in terms of mean reduction in IOP from baseline (no meta-analysis).Two RCTs compared treatment with iStent to medical therapy; one of the two trials used the iStent inject. We determined the two trials to be clinically and methodologically heterogeneous and did not conduct a meta-analysis; however, the investigators of both trials reported that over 90% of participants in the treatment groups were drop-free compared to no participants in the medical therapy groups at six to 18 months.One RCT compared treatment with one versus two versus three iStents. There was no difference in terms of participants who were drop-free at 36 months or less; however, at longer follow-up (i.e. at 42 months) participants in the one iStent treatment were less likely to be drop-free than those in the two iStent (RR 0.51, 95% CI 0.34 to 0.75) or three iStent (RR 0.49, 95% CI 0.34 to 0.73) treatment groups. The study did not report the mean change in number of IOP-lowering drops.The type and timing of complications reported varied by RCTs. Similar proportions of participants who underwent treatment with iStent in combination with phacoemulsification and who underwent phacoemulsification alone needed secondary glaucoma surgery. None of RCTs reported findings related to quality of life.

AUTHORS' CONCLUSIONS

There is very low-quality evidence that treatment with iStent may result in higher proportions of participants who are drop-free or achieving better IOP control, in the short, medium, or long-term. Results from the 13 studies with results not yet available may clarify the benefits of treatment of people with iStent. Additionally, future MIGS studies should consider measuring quality of life and outcomes that reflect people's ability to perform vision-dependent activities.

Cost-effectiveness analysis of iStent trabecular micro-bypass stent for patients with open-angle glaucoma in Colombia

OBJECTIVE

To estimate the cost-effectiveness of trabecular micro bypass stent vs laser trabeculoplasty or medications only, for patients with open-angle glaucoma in a setting of the Colombian System Health.

METHODS

This is a cost-effectiveness analysis that based its assumptions in external data sources, used to extrapolate the quality-of-life related to health, survival, and costs. A Markov model, with stages from 0 (ocular hypertension without glaucoma) to 5 and bilateral blindness, was developed inclusive of Colombians older than 40 years in 2018, from a societal perspective, comparing trabecular micro-bypass stents vs laser trabeculoplasty, timolol + dorzolamide + brimonidine, timolol + dorzolamide + latanoprost, or timolol + dorzolamide + brimatoprost, in terms of clinical and economic outcomes over a lifetime horizon. Both costs and health outcomes had an annual rate discount of 5%. Health outcomes were evaluated in terms of QALYs related with loss of visual acuity. Trabecular micro-bypass costs include the joint use of timolol, and the costs of laser trabeculoplasty include the combined use of timolol + dorzolamide.

RESULTS

Trabecular micro-bypass stents were estimated to have 127,971 more discounted QALYs vs laser trabeculoplasty; 405,982 vs timolol + dorzolamide + brimonidine; and 378,287 vs timolol + dorzolamide + latanoprost or timolol + dorzolamide + brimatoprost. Cumulative costs with trabecular micro-bypass stents at 40 years was $13,252,318 lower than laser trabeculoplasty; $6,403,534, lower than timolol + dorzolamide + brimonidine; $22,311,064, lower than timolol + dorzolamide + latanoprost; and $29,156,113 lower than timolol + dorzolamide + brimatoprost.

CONCLUSIONS

The trabecular micro-bypass stent is a highly cost-saving strategy due to more QALYs related to a lower rate of the population with loss of visual acuity in the long-term, and because the costs associated with additional medications and complications are lower with trabecular micro-bypass stents.

Effect of Community Screening on the Demographic Makeup and Clinical Severity of Glaucoma Patients Receiving Care in Urban China

PURPOSE

To assess differences in clinical and demographic characteristics between glaucoma patients identified by community screening and those newly diagnosed in hospital in a Chinese setting.

DESIGN

Prospective comparative cohort study.

METHODS

A total of 373 patients identified with glaucoma among 27 000 persons undergoing community screening were enrolled as the Screening group. The Clinic group consisted of 119 consecutively presenting, newly diagnosed glaucoma patients in hospital. Primary outcomes were mean deviation (MD), visual field index (VFI) and pattern standard deviation (PSD) on Humphrey Field Analyzer, and intraocular pressure (IOP). Disease severity was categorized into 5 stages based on MD.

RESULTS

A total of 89.6% (328/373) of Screening group patients had IOP < 21 mm Hg, compared to 48.7% (58/119) in the Clinic group (P < .001). The mean VFI, MD, and PSD were 76.4% ± 23.8%, -9.7 ± 7.3 dB, and 6.4 ± 3.4 dB in the Screening group and significantly worse in the Clinic group: 44.1% ± 32.0%, -19.8 ± 9.5 dB, and 7.6 ± 3.1 dB (P < .001 for MD and VFI, P = .001 for PSD). Nearly three quarters of Screening patients had early or moderate visual field loss (monocular), while nearly half of Clinic patients had severe loss at the time of diagnosis. Screening patients were significantly more likely to be older (P < .001) and female (P < .001) than Clinic patients.

CONCLUSION

Glaucoma patients detected through community screening had significantly milder damage, and were more likely to include underserved groups (women, elderly) than those newly diagnosed in a clinic in this setting. Comparison with population studies suggests that cases of glaucoma with IOP < 21 mm Hg are severely underascertained in China, a situation that may be improved by screening.

Pressure Control in Glaucoma Patients after Cataract Surgery with Intraocular Lens

In a retrospective study 97 patients with glaucoma and 16 with ocular hypertension were examined with regard to intraocular pressure (IOP) after extracapsular cataract extraction with implantation of a posterior chamber lens. During the follow-up 39 cases dropped out but 63 glaucoma patients and 11 patients with ocular hypertension were followed for three years.

Compared to preoperative IOP 59% of the patients treated previously with Argon laser trabeculoplasty (ALT) had an IOP rise of > 10 mm Hg the day after surgery. The corresponding proportion among medically treated patients was 34% (P=0.01). A pressure rise of > 10 mm Hg was less frequent among patients treated with one drug than among those treated with two or three (P=0.05). During follow-up eight patients had a pressure rise which could not be controlled medically and they had to undergo additional ALT or surgery. All eight had been treated with ALT or with glaucoma filtering surgery prior to the cataract operation.

After three years observation of 63 of the glaucoma patients, 63% were having less medical therapy than preoperatively, 30% an equal amount and 7% more; 49% (31 of 63) were still without any therapy. In the group of patients who preoperatively were only treated medically, no definite increase in therapy was needed in the long term.

Characterization of Intraocular Pressure Increases and Management Strategies Following Treatment With Fluocinolone Acetonide Intravitreal Implants in the FAME Trials

BACKGROUND AND OBJECTIVE

To compare elevated intraocular pressure (IOP) management and outcomes among patients with diabetic macular edema who received fluocinolone acetonide (FAc) implants versus sham-control treatment and explore the prior ocular steroid exposure impact on IOP outcomes.

PATIENTS AND METHODS

Best-corrected visual acuity (BCVA) was measured using Early Treatment Diabetic Retinopathy Study charts or electronic VA testers. Goldmann applanation tonometry was used to measure IOP.

RESULTS

Elevated IOP was more common in FAc-versus sham control-treated patients. Medication, and less often trabeculoplasty or surgery, was used to lower IOP without affecting VA outcomes. No patient treated with 0.2 µg/day FAc who received prior ocular steroid required IOP-lowering surgery.

CONCLUSION

Elevated IOP may occur following FAc implant receipt; however, in the present study, it was manageable and did not impact vision outcomes. Patients previously treated with ocular steroid did not require IOP-lowering surgery following 0.2 µg/day FAc implant administration. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:426-435.].

Goniosynechialysis and Repositioning of Intraocular Lens in a Case of Secondary Angle Closure Glaucoma

PURPOSE

Implanting intraocular lens (IOL) in proper direction is important in cataract surgery to reduce the possibility of undesirable complications. We experienced a case who underwent vitrectomy combined with cataract surgery and developed secondary angle closure glaucoma caused by IOL misdirection. Goniosynechialysis (GSL) and repositioning of IOL successfully ameliorated the high intraocular pressure (IOP).

CASE REPORT

A 64-year-old male with massive vitreous hemorrhage underwent vitrectomy combined with cataract surgery. In implanting IOL, posterior capsule was accidentally raptured, and we were obliged to implant IOL reversely in the ciliary sulcus. A month postoperatively, the capture of IOL by iris and the shallow anterior chamber with iris bombe formation led to the elevated IOP up to 60 mmHg. Laser iridotomy and maximum anti-glaucoma medications including oral carbon anhydrase inhibitor could not control IOP. Subsequently, we performed GSL and IOL repositioning to correct the lens direction and the IOP was successfully reduced to normal level.

CONCLUSION

Reversely sulcus-implanted IOL should be repositioned to prevent secondary angle closure glaucoma.

[Ophthalmology in 2016 : the advent of ocular biomarkers]

Precision medicine is the future. In all fields of medicine, optimized therapy aims at identifying individuals at risks in order to prevent diseases, to identify specific molecular targets in a specific patient, at a specific time, to administer optimized treatment with less side effects. To achieve this ambitious aim, biomarkers, which should be specific and sensitive predictive indicators of diseases, or of response to treatment or of a state of evolution of the disease, must be identified. The eye offers an easy access organ to collect directly media or tissue, which can serve to identify such markers. This paper summarizes recent advances in the identification of ocular biomarkers of ocular diseases but also of brain diseases.

The Pathway From Genes to Gene Therapy in Glaucoma: A Review of Possibilities for Using Genes as Glaucoma Drugs

Treatment of diseases with gene therapy is advancing rapidly. The use of gene therapy has expanded from the original concept of re-placing the mutated gene causing the disease to the use of genes to con-trol nonphysiological levels of expression or to modify pathways known to affect the disease. Genes offer numerous advantages over conventional drugs. They have longer duration of action and are more specific. Genes can be delivered to the target site by naked DNA, cells, nonviral, and viral vectors. The enormous progress of the past decade in molecular bi-ology and delivery systems has provided ways for targeting genes to the intended cell/tissue and safe, long-term vectors. The eye is an ideal organ for gene therapy. It is easily accessible and it is an immune-privileged site. Currently, there are clinical trials for diseases affecting practically every tissue of the eye, including those to restore vision in patients with Leber congenital amaurosis. However, the number of eye trials compared with those for systemic diseases is quite low (1.8%). Nevertheless, judg-ing by the vast amount of ongoing preclinical studies, it is expected that such number will increase considerably in the near future. One area of great need for eye gene therapy is glaucoma, where a long-term gene drug would eliminate daily applications and compliance issues. Here, we review the current state of gene therapy for glaucoma and the possibilities for treating the trabecular meshwork to lower intraocular pressure and the retinal ganglion cells to protect them from neurodegeneration.

[Diagnosis and treatment of ocular hypertension]

Ocular hypertension is popular among people, with a prevalence of 3% to 10% in those older than 40 years old. Without proper intervention, over 10% of the patients with ocular hypertension would develop glaucoma in the following 5 to 10 years. Glaucoma has become one of the leading causes of blindness all over the world, which makes it essential for us to pay enough attention to the prevention and treatment of ocular hypertension. However, it is not cost-effective to treat all the patients with ocular hypertension. Certain side effects may also be caused with long-term medical treatment. Therefore, it is of great importance for ophthalmologists to identify the right time and use appropriate therapeutic methods. To introduce the knowledge of ocular hypertension, the definition, epidemiology, diagnosis, risk factors and treatment of ocular hypertension are reviewed in this article. (Chin J Ophthalmol, 2016, 52: 542-546).

Neuroprotective effects of intravitreally transplanted adipose tissue and bone marrow-derived mesenchymal stem cells in an experimental ocular hypertension model

BACKGROUND AIMS

The purpose of this study was to investigate the neuroprotective effects of bone marrow bone marrow-derived and adipose tissue-derived mesenchymal stromal cells (MSCs) that were intravitreally transplanted in an experimental ocular hypertension (OHT) model.

METHODS

An OHT rat model was generated by means of intracameral injection of hyaluronic acid into the anterior chamber. MSCs labeled with green fluorescence protein were transplanted intravitreally 1 week after OHT induction. At the end of the second and fourth weeks, retinal ganglion cells were visualized with the use of a flat-mount retina method and were evaluated by means of immunofluorescence staining against green fluorescence protein, vimentin, CD105, and cytokines (interleukin [IL]-1Ra, prostaglandin E2 receptor, IL-6, transforming growth factor-β1, interferon-γ and tumor necrosis factor-α).

RESULTS

The retinal ganglion cell numbers per area were significantly improved in stem cell-treated OHT groups compared with that in the non-treated OHT group (P < 0.05). The results of immunohistochemical analyses indicated that a limited number of stem cells had integrated into the ganglion cell layer and the inner nuclear layer. The number of cells expressing proinflammatory cytokines (interferon-γ and tumor necrosis factor-α) decreased in the MSC-transferred group compared with that in the OHT group after 4 weeks (P < 0.01). On the other hand, IL-1Ra and prostaglandin E2 receptor expressions were increased in the rat bone marrow-derived MSC group but were more significant in the rat adipose tissue-derived MSC group (P < 0.01).

CONCLUSIONS

After intravitreal transplantation, MSCs showed a neuroprotective effect in the rat OHT model. Therefore, MSCs promise an alternative therapy approach for functional recovery in the treatment of glaucoma.

A laser-induced mouse model with long-term intraocular pressure elevation

Purpose

To develop and characterize a mouse model with intraocular pressure (IOP) elevation after laser photocoagulation on the trabecular meshwork (TM), which may serve as a model to investigate the potential of stem cell-based therapies for glaucoma.

Methods

IOP was measured in 281 adult C57BL/6 mice to determine normal IOP range. IOP elevation was induced unilaterally in 50 adult mice, by targeting the TM through the limbus with a 532-nm diode laser. IOP was measured up to 24 weeks post-treatment. The optic nerve damage was detected by electroretinography and assessed by semiautomatic counting of optic nerve axons. Effects of laser treatment on the TM were evaluated by histology, immunofluorescence staining, optical coherence tomography (OCT) and transmission electron microscopy (TEM).

Results

The average IOP of C57BL/6 mice was 14.5±2.6 mmHg (Mean ±SD). After laser treatment, IOP averaged above 20 mmHg throughout the follow-up period of 24 weeks. At 24 weeks, 57% of treated eyes had elevated IOP with the mean IOP of 22.5±2.5 mmHg (Mean ±SED). The difference of average axon count (59.0%) between laser treated and untreated eyes was statistically significant. Photopic negative response (PhNR) by electroretinography was significantly decreased. CD45+ inflammatory cells invaded the TM within 1 week. The expression of SPARC was increased in the TM from 1 to 12 weeks. Histology showed the anterior chamber angle open after laser treatment. OCT indicated that most of the eyes with laser treatment had no synechia in the anterior chamber angles. TEM demonstrated disorganized and compacted extracellular matrix in the TM.

Conclusions

An experimental murine ocular hypertension model with an open angle and optic nerve axon loss was produced with laser photocoagulation, which could be used to investigate stem cell-based therapies for restoration of the outflow pathway integrity for ocular hypertension or glaucoma.

Rate of visual field progression in eyes with optic disc hemorrhages in the ocular hypertension treatment study

OBJECTIVE

To compare rates of visual field (VF) change in ocular hypertensive eyes with and without optic dischemorrhage (DH).

METHODS

Ocular Hypertension Treatment Study subjects(minimum 10 reliable VF tests, followed up 5 years) were included. Trend analyses of VF sequences over time of DH and non-DH eyes were assessed by regression of mean deviation (MDR) and pointwise linear regression (PLR). The main outcome measures were rates of VF change in DH and non-DH eyes.

RESULTS

Two thousand six hundred seven eyes (1378 participants) were included. The mean (SD) number of VF tests per eye was 23.7 (4.9) spanning a mean (SD) of 12.2 (2.0) years. At least 1 DH was detected in 187 eyes(7.2%), of which 52 eyes had recurrent DH. Mean deviation rate of change was significantly worse in DH compared with non-DH eyes (mean [SD], −0.17 [0.27] vs−0.07 [0.19] dB/y; P<.01). Significant PLR progression occurred more frequently in eyes with DH (odds ratio,3.6; P<.01), which increased when 2 or more DHs were present (odds ratio, 4.2; P=.01). Eyes initially randomized to treatment were less likely to have a DH during follow-up.

CONCLUSIONS

Eyes with DH had more rapid VF deterioration when assessed by global (MDR) or local (PLR)trend analysis than eyes without DH. Eyes with recurrent DH had similar rates of global VF change (MDR)when compared with eyes with a single DH but reached criteria for rapid PLR change more often. Intraocular pressure reduction in ocular hypertension reduces the risk of developing a DH. Ocular hypertensive eyes with DH should be monitored closely and may need more aggressive therapy.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00000125

Clinical analysis of early and mid-late elevated intraocular pressure after silicone oil injection

PURPOSE

To discuss the incidence and clinical features of early and mid-late elevated intraocular pressure after pars plana vitrectomy and silicone oil injection, and to evaluate the clinical management of eyes with secondary glaucoma.

METHODS

This was an observational consecutive case series of 691 eyes in 679 patients who were treated with pars plana vitrectomy and silicone injection. The diagnostic criteria of early elevated intraocular pressure after silicone oil injection was ≥ 21 mmHg two weeks after surgery, while mid-late elevated intraocular pressure was ≥ 21 mmHg after two weeks. The incidence and clinical management of elevated intraocular pressure were analyzed.

RESULTS

In total, 211 of 691 eyes (30.54%) developed elevated intraocular pressure two weeks after pars plana vitrecto my and silicone injection. Of the 211 eyes, 101 eyes (47.87%) had ocular inflammation, 64 eyes (30.33%) showed hyphema, 35 eyes (16.59%) had silicone oil in the anterior chamber, 6 eyes (2.84% ) had excess silicone oil injected, and 5 eyes (2.37%) had rubeosis irides. Eighty three of 691 eyes (12.01%) developed elevated intraocular pressure after two weeks. Of these 83 eyes, 25 eyes (30.12%) had rubeosis irides, 16 eyes (19.27%) had issues related to topic steroid therapy, 13 eyes (15.66%) had a papillary block, silicone oil in the anterior chamber, 10 eyes (12.05%) had a silicone emulsion, 10 eyes (12.05%) had peripheral anterior synchiae, and 9 eyes (10.84%) had silicone oil in the anterior chamber. All eyes with elevated intraocular pressure were treated with antiglaucoma medications and surgeries.

CONCLUSION

The reasons for elevated intraocular pressure differed between early and mid-late after pars plana vitrectomy and silicone oil injection. The elevated intraocular pressure can be controlled effectively by immediate diagnosis and proper treatment with medicine and operation.

Iridocorneal endothelial syndrome in a Chinese child

PURPOSE

We reported a rare case of ICE syndrome in a Chinese child.

CASE REPORT

A 6-year-old child was admitted to the ophthalmology department of the Affiliated Wuxi Second Hospital of Nanjing Medical University, complaining of elevated intraocular pressure at his first diagnosis in a local hospital. The patient was initially treated with medication. During subsequent follow up, two iris holes were seen in the patient's right eye and he was then diagnosed with ICE syndrome. The child underwent surgery combined with mitomycin C intraoperatively. The intraocular pressure was stably controlled.

CONCLUSION

ICE syndrome has been rarely reported in children. Glaucoma filtering surgery combined with intraoperative administration of mitomycin is efficacious for intraocular pressure control.

Long-term risk of glaucoma after congenital cataract surgery

PURPOSE

To report the long-term risk of glaucoma development in children following congenital cataract surgery.

DESIGN

Retrospective interventional consecutive case series.

METHODS

We retrospectively reviewed the records of 62 eyes of 37 children who underwent congenital cataract surgery when <7 months of age by the same surgeon using a limbal approach. The Kaplan-Meier method was used to calculate the probability of an eye's developing glaucoma and/or becoming a glaucoma suspect over time.

RESULTS

The median age of surgery was 2.0 months and the median follow-up after cataract surgery was 7.9 years (range, 3.2-23.5 years). Nine eyes (14.5%) developed glaucoma a median of 4.3 months after cataract surgery and an additional 16 eyes (25.8%) were diagnosed as glaucoma suspects a median of 8.0 years after cataract surgery. The probability of an eye's developing glaucoma was estimated to be 19.5% (95% CI: 10.0%-36.1%) by 10 years after congenital cataract surgery. When the probability of glaucoma and glaucoma suspect were combined, the risk increased to 63.0% (95% CI: 43.6%-82.3%).

CONCLUSIONS

Long-term monitoring of eyes after congenital cataract surgery is important because we estimate that nearly two thirds of these eyes will develop glaucoma or become glaucoma suspects by 10 years after cataract surgery.

[Tube versus trabeculectomy study]

Epibulbar glaucoma drainage devices have been only slightly modified since their introduction more than 40 years ago. Having been used primarily in only difficult cases with a poor prognosis (and therefore with poor clinical results) the recently published trabeculectomy versus tube study (TVT) led to a change in our understanding of these devices. In this study epibulbar glaucoma drainage devices (here the Baerveldt device) were employed for early implantation (in some cases as primary glaucoma surgery intervention). Being sceptically monitored the results over the first 5 year clearly showed an almost equal or even better outcome in comparison to trabeculectomy. Despite these good results a critical evaluation seems mandatory mainly because of the unsolved problems concerning late complications. Late tube erosion with subsequent blebitis and enophthalmitis as well as late base plate encapsulation need to be mentioned here. The latter leads to thick fibrous tissue around the base plate resulting in an increase of intraocular pressure (IOP). Late corneal decompensation is also a late complication the pathomechanism of which is only poorly understood. Solving and treating such late complications are often troublesome and time consuming. Future experiments should lead to development of new drainage implant designs and the bulk material should be enhanced and optimized to increase clinical surgical results.

Direct cost and predictive factors for treatment in patients with ocular hypertension or early, moderate and advanced primary open-angle glaucoma: the CoGIS study in Germany

BACKGROUND

The main objectives of this analysis were to assess the treatment costs and to identify major cost drivers and factors predicting direct costs in German patients with ocular hypertension (OHT) or primary open-angle glaucoma (POAG).

METHODS

This non-interventional cross-sectional study was conducted in two university hospitals and 13 ophthalmology practices in Germany regions (Bavaria, Rhineland-Palatinate, North Rhine-Westphalia, Hamburg and Mecklenburg-Western Pomerania) between May 2009 and January 2010 to assess resource utilisation in patients with OHT (ICD-10: 40.0) or POAG (ICD-10: 40.1) at early, moderate or advanced stages, according to the European Glaucoma Society classification Guidelines. Treatment patterns and direct costs were evaluated retrospectively for 5 years. Resource utilisation data (medication, hospitalisation, outpatient surgery, visits to ophthalmologists) were abstracted from the charts, and unit costs were applied to estimate direct costs per year (in Euros, 2009), calculated from the perspective of the statutory health insurance in Germany (Gesetzliche Krankenversicherung). Factors predicting costs were assessed in multivariate regression analysis.

RESULTS

One hundred and fifty-four patients (17.5% OHT, 27.9% early, 22.7% moderate, and 31.8% advanced POAG), on average 67 years old (SD 11) were included in the study. Average total annual direct costs per patient for OHT were <euro>226 (SD 117), for early POAG <euro>423 (SD 647), moderate <euro>493 (SD 385) and advanced POAG <euro>809 (SD 877). Glaucoma-related medications and hospitalisation represented the two major components of direct costs, increasing with the progression of glaucoma. In addition to treatment switches (p = 0.0001), factors predictive of an increase in total direct costs included the number of hospital interventions (p < 0.0001), disease-state changes since the start of treatment (p = 0.05), and current disease state (p = 0.05).

CONCLUSIONS

Direct costs of treatment are higher in glaucoma compared to OHT and further increase in more severe glaucoma states. Additional treatment changes are major contributing factors to the increased treatment costs of glaucoma. If intraocular pressure can be controlled over the long term, progression to moderate and advanced states avoided, and patients remain on initial treatments, treatment costs could decline due to reduced and less expensive healthcare resource utilisation.

Electrophysiological tests in evaluation of glaucoma and ocular hypertension treatment--up to date knowledge. A review

PURPOSE

On the basis of the literature data to assess the efficacy of the electrophysiological tests (pattern electroretinogram, multifocal electroretinogram and multifocal visual evoked potentials) in evaluation of retinal ganglion cells function in glaucomatous and ocular hypertension eyes, after intraocular pressure reduction.

MATERIAL AND METHODS

Data published in the literature available at the Pub Med library between 1964-2012.

RESULTS

Several results of studies suggest, that steady-state pattern electroretinogram reveals significant improvement of retinal ganglion cells function after treatment with timolol, acatazolamide, beta-blockers and prostaglandin analogues. Multifocal electroretinograms' changes, after lowering the intraocular pressure by trabeculectomy, were confirmed in only one study, There were no statistically significant correlations between changes in intraocular pressure reduction and multifocal visual evoked potentials.

CONCLUSIONS

Steady state pattern electroretinogram is the most commonly used electrophysiological test in evaluating the results of glaucoma and ocular hypertension treatment.

Effectiveness of a short message reminder in increasing compliance with pediatric cataract treatment: a randomized trial

OBJECTIVE

Regular follow-up is essential to successful management of childhood cataract. We sought to assess whether a mobile phone short message service (SMS) for parents of children with cataract could improve follow-up adherence and the proportion of procedures performed in timely fashion.

DESIGN

Randomized, controlled trial. This trial is registered with ClinicalTrials.gov, NCT01417819.

PARTICIPANTS

We included 258 parent-child pairs involved in the Childhood Cataract Program of the Chinese Ministry of Health.

METHODS

Participants were randomized (1:1) to a mobile phone SMS intervention or standard follow-up appointments. All participants were scheduled to attend ≥ 4 follow-up appointments according to the protocol. Parents in the intervention group received SMS automated reminders before scheduled appointments. The control group parents did not receive SMSs or any alternative reminder of scheduled appointments. Regular ocular examinations and analyses were performed by investigators masked to group allocation; however, study participants and the manager in charge of randomization and sending SMSs were not masked.

MAIN OUTCOME MEASURES

Number of follow-up appointments attended, additional surgeries, laser treatments, changes in eyeglasses prescription, and occurrence of secondary ocular hypertension.

RESULTS

Among parent-child participants, 135 were randomly assigned to the SMS intervention and 123 to standard appointments. Attendance rates for the SMS group (first visit, 97.8%; second, 91.9%; third, 92.6%; fourth, 83%) were significantly higher than those for the control group (first visit, 87.8%; second, 69.9%; third, 56.9%; fourth, 33.3%). The increase in attendance rate for total number of follow-up visits with SMS reminders was 47.2% (relative risk [RR] for attendance, 1.47; 95% confidence interval [CI], 1.16-1.78; P = 0.003). The number needed to remind (NNR) to gain 1 additional visit by 1 child was 3 (95% CI, 1.8-4.2). A total of 247 clinical interventions were carried out in the SMS group and 134 in the control group (RR, 1.68; 95% CI, 1.37-1.99; P = 0.007). The NNR to result in 1 additional clinical intervention was 5 (95% CI, 3.5-6.5).

CONCLUSIONS

The SMS reminders significantly improved follow-up adherence in pediatric cataract treatment. Using readily available mobile phone resources may be an effective and economic strategy to improve management of childhood cataract in China.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.

[Management of juvenile ocular hypertension]

Ocular hypertensions (OHTs) in juvenile are characterized by occurrence in teenage with intraocular pressure (IOP) frequently fluctuated and increased over 30 mm Hg (1 mm Hg = 0.133 kPa) without any ocular symptoms and disturbance of visual acuity. IOPs are normalized in the majorities of juvenile over adolescence stage with long-term follow up. The medical terminology of 'adolescence IOP fluctuation' or 'adolescence ocular hypertension' is therefore used. The diagnosis and management of juvenile OHT remain difficult clinical challenges. OHTs in juvenile sometimes are incorrectly diagnosed due to inappropriate IOP measurement and thicker central cornea as younger children are non-compliant and resisting the examination. In this paper, we reviewed OHT in juvenile in the light of significant studies in the past and based on our experience of clinical practice in order to provide a better understanding and management of OHTs in juvenile.

[Intraocular hypertension after retinal detachment surgery]

This papers presents a case of a patient with retinal detachment, 3 days ago operated (posterior vitrectomy, internal tamponament with silicon oil 1000) who developed increased ocular pressure following silicon oil output in the anterior chamber.

[Ocular hypertension after surgery for retinal detachment]

This papers presents a case of a patient with retinal detachement, 3 days ago operated (posterior vitrectomy internal tamponament with silicon oil 1000) who develop increased ocular pressure following silicon oil output in the anterior chamber.

Ocular injuries from shake and bake methamphetamine labs

PURPOSE

To review ocular injuries resulting from "shake and bake" methamphetamine labs.

METHOD

Retrospective case series of 4 patients with ocular injuries sustained from "shake and bake" lab explosions.

RESULTS

Four men ages 20-39 underwent complete ophthalmologic examination after an injury from a "shake and bake" methamphetamine lab explosion.The mechanism of injury was initially misrepresented in each case; the physical findings were suggestive of thermal and alkali injury. Visual acuity ranged widely from 20/20 to light perception only. Treatment in the acute setting included irrigation, pH monitoring, and intraocular pressure lowering.

CONCLUSION

Methamphetamine production by means of the"shake and bake" method can result in combined thermal and alkali ocular injury. Patients who sustain this type of injury may not accurately report the mechanism of exposure. Increased awareness of this type of ocular injury may increase the rapidity of diagnosis, avoid early misdiagnosis, and ultimately improve outcomes.

Subconjunctival reflux and need for paracentesis after intravitreal injection of 0.1 ml bevacizumab: comparison between 27-gauge and 30-gauge needle

PURPOSE

Intravitreal injections may lead to a significant elevation of the intraocular pressure (IOP). A paracentesis may become necessary for acute reduction of the IOP in certain cases. The purpose of this study was to determine the frequency of paracentesis performed and the grade of reflux under the conjunctiva after injection of 0.1 ml bevacizumab (1.25 mg), depending on the thickness of the needles used.

METHODS

A retrospective review was undertaken of the surgery reports of 234 consecutive intravitreal bevacizumab injections in 145 eyes of 144 patients within 14 months. In particular, the frequency of paracentesis, the thickness of the needles used (27-gauge versus 30-gauge), the lens status, and a semi-quantitative reflux grade were analysed.

RESULTS

A paracentesis was performed in 78 cases (33%) for acute reduction of the IOP. In the 27-gauge group the frequency was 26% (25 of 96), and in the 30-gauge group 38% (53 of 138) (p = 0.05, independent estimating equation (IEE)). The medians of the semi-quantitative assessment of the reflux grade under the conjunctiva were 2.0 in the 27-gauge group (corresponding to a mild reflux) and 1.0 in the 30-gauge group (corresponding to a minimal reflux, p < 0.001, IEE).

CONCLUSIONS

When using a 30-gauge needle for intravitreal injections, the reflux under the conjunctiva was less than with a 27-gauge needle. However, the use of a 30-gauge needle appeared to be associated with a higher frequency of paracentesis.

[Effect of acupuncture on the expression of Bcl-xl and BDNF of retina in rabbits with chronic intraocular hypertension]

OBJECTIVE

To explore the protection effects of acupuncture on glaucomatous optic nerve damage and its mechanism.

METHODS

Experimental glaucoma model was induced by intracameral injection of compound Carbomer solution in rabbits. After 28 days, ocular tension returned to normal by filtration surgery. Twenty rabbits (40 eyes) were randomly divided into a model group, an acupuncture group, a neurotrophy group and a nomal control group, 5 cases in each group. The acupuncture group was treated with acupuncture at bilateral "Qiuhou" (EX-HN 7),"Fengchi" (GB 20) and "Xingjian" (LR 2), twice a day. The neurotrophy group was treated with intramuscular injection of Vitamin B1 (100 mg) and Vitamin B12 (500 microg), once a day, and the other groups with no treatment. The expressions of Bcl-xl and BDNF in rabbits retina were observed after 4 weeks.

RESULTS

At the end of the experiment, the positive expression cells of Bcl-xl and BDNF were (31.20 +/- 5.97) per mm2 and (6.3 +/- 1.89) per mm2 in the acupuncture group, being significantly higer than (26.70 +/- 4.32) per mm2 and (4.0 +/- 1.89) per mm2 in the model group (both P<0.05).

CONCLUSION

Acupuncture can raise the expression of Bcl-xl and BDNF of retina, so as to prevent optic nerve damage caused by intraocular hypertension.

Modeling complex treatment strategies: construction and validation of a discrete event simulation model for glaucoma

OBJECTIVE

Discrete event simulation (DES) modeling has several advantages over simpler modeling techniques in health economics, such as increased flexibility and the ability to model complex systems. Nevertheless, these benefits may come at the cost of reduced transparency, which may compromise the model's face validity and credibility. We aimed to produce a transparent report on the construction and validation of a DES model using a recently developed model of ocular hypertension and glaucoma.

METHODS

Current evidence of associations between prognostic factors and disease progression in ocular hypertension and glaucoma was translated into DES model elements. The model was extended to simulate treatment decisions and effects. Utility and costs were linked to disease status and treatment, and clinical and health economic outcomes were defined. The model was validated at several levels. The soundness of design and the plausibility of input estimates were evaluated in interdisciplinary meetings (face validity). Individual patients were traced throughout the simulation under a multitude of model settings to debug the model, and the model was run with a variety of extreme scenarios to compare the outcomes with prior expectations (internal validity). Finally, several intermediate (clinical) outcomes of the model were compared with those observed in experimental or observational studies (external validity) and the feasibility of evaluating hypothetical treatment strategies was tested.

RESULTS

The model performed well in all validity tests. Analyses of hypothetical treatment strategies took about 30 minutes per cohort and lead to plausible health-economic outcomes.

CONCLUSION

There is added value of DES models in complex treatment strategies such as glaucoma. Achieving transparency in model structure and outcomes may require some effort in reporting and validating the model, but it is feasible.

Treatment of sheep steroid-induced ocular hypertension with a glucocorticoid-inducible MMP1 gene therapy virus

PURPOSE

To investigate whether intracameral injection of the adenovirus vector AdhGRE.MMP1 would reduce or prevent elevated intraocular pressure (IOP) induced by corticosteroids in living animals.

METHODS

Glucocorticoid-inducible adenovirus vectors carrying wild-type or mutant forms of human metalloproteinase 1 (MMP1 and mutMMP1) cDNAs were generated. An adenovirus carrying no gene (Ad5.CMV.Null) was used as an additional control. Sheep were injected intracamerally with 30 microL of each vector, either previously or after the induction of increased IOP with topical prednisolone or sub-Tenon triamcinolone under various protocols. IOP was measured with a Perkins tonometer. Inflammation was monitored by visual inspection.

RESULTS

In eyes in which IOP was already elevated to 24 to 30 mm Hg, injection of AdhGRE.MMP1 reduced IOP by 70% in 24 hours and to 10 to 13 mm Hg in 48 hours. In eyes with normal IOP (9-11 mm Hg), preinjection of the virus protected against the increase in IOP normally produced by the corticosteroid. IOP remained at a level of approximately 12 mm Hg for 5 days despite the continuous application of the corticosteroid. Injections of the control viruses had no hypotensive effects. There were no signs of ocular inflammation or discomfort to the animals.

CONCLUSIONS

A single dose of a gene therapy vector carrying an inducible metalloproteinase human gene can both protect against the IOP increase produced by corticosteroid instillation in the sheep model and quickly reverse the IOP increase previously elicited by the corticosteroid. These results are a first step toward a treatment of steroid-glaucoma with inducible overexpression of extracellular matrix modulator genes.

Incorporating mortality risk into estimates of 5-year glaucoma risk

PURPOSE

To incorporate mortality risk, a potentially important factor to consider when deciding whether to initiate therapy for ocular hypertensives, into estimates of 5-year glaucoma risk.

DESIGN

Comparison study of estimates of glaucoma risk that do and do not account for mortality risk.

METHODS

We computed 5-year risk of glaucoma for a set of hypothetical glaucoma suspects. We then determined their 5-year risk of death using the Charlson index, which is based on age and comorbidity, and computed mortality-adjusted 5-year risk that the individual will develop glaucoma before death.

RESULTS

Accounting for mortality risk reduces the risk of developing glaucoma in one's lifetime. For example, a 75-year-old patient with an unadjusted 5-year glaucoma risk of 51.0% can have mortality-adjusted 5-year glaucoma risks of 41.8% (18% relative risk reduction) or 20.2% (60% relative risk reduction) assuming the patient has a Charlson comorbidity score of 1 or 3, respectively.

CONCLUSIONS

Shortened life expectancy reduces 5-year risk of developing glaucoma. Thus, mortality risk is another factor clinicians should consider when deciding whether to initiate treatment of glaucoma suspects.

Healthcare charges in patients who transition from ocular hypertension to primary open-angle glaucoma based on ophthalmic coding data

INTRODUCTION

The purpose of this research was to assess the impact of transition from ocular hypertension (OHT) to primary open-angle glaucoma (POAG) on healthcare charges.

METHODS

A case-control group was identified using PharMetrics claims database (1998-2005). Cases (n=1055) had a transition from OHT to POAG based on International Classification of Disease, Ninth Edition coding (ICD-9=365.11). Controls (n=2110) retained an ICD-9 code for OHT (ICD-9=365.04) and were matched to cases (2:1) on gender, age, diagnosis year, and follow-up time post-diagnosis. The index date marked the transition for cases and a date of similar duration after OHT diagnosis for controls. Conditional logistic regression and multiple linear regression models determined the impact of transitioning on healthcare charges.

RESULTS

Cases had significantly higher increases in ophthalmology-related charges ($797 vs. -$385, P<0.0001) but similar total healthcare charges ($1689 vs. $1386, P=0.8277) from the year pre- to year post-index date when compared with controls. After adjusting for key covariates, cases were 1.56 times (95% CI: 1.33-1.82) more likely to have increased total charges and 5.26 times (95% CI: 4.27-6.47) more likely to have increased ophthalmology-related charges compared with controls. In multiple linear regression analyses, cases experienced $48 (55%) higher increases in ophthalmology-related charges from the year pre- to year post-index date compared with controls ($85 vs. $37, respectively; P<0.0001).

CONCLUSION

Patients with a transition from OHT to POAG based on ICD-9 coding had higher ophthalmology-related charges the year after transition compared with patients who retained a code for OHT. Prevention of this transition could result in healthcare resource savings.

The medical and surgical treatment of glaucoma

BACKGROUND

Ongoing demographic changes in Europe are heightening the importance of adequate treatment for glaucoma, a disorder that is markedly more common in the elderly.

METHOD

A selective search for relevant literature, including Cochrane Reviews and the guidelines of the European Glaucoma Society, regarding the topical and surgical treatment of glaucoma.

RESULTS

It is recommended that the intraocular pressure (IOP) should be lowered by 20% to 50% from its baseline value, depending on the extent of already existing damage, the rate of progression, the baseline IOP, and the age of the patient. Topical monotherapy can lower the IOP by 15% to 30%. The success rate of filtration surgery has risen because of the intraoperative application of topical antimetabolites and currently ranges from 50% to 90%, depending on the study.

CONCLUSIONS

The goal of glaucoma treatment is to protect the patient from blindness and visual impairment while keeping the treatment-related decline in quality of life to a minimum. Any type of glaucoma treatment, be it medical or surgical, must further this aim in consideration of the situation of the individual patient.

[Neuroprotective effect of rAAV-mediated rhBDNF gene transfection on rabbit retina against acute high intraocular pressure]

OBJECTIVE

To investigate the neuroprotective effect of human brain-derived neurotrophic factor gene transfection into rabbit retina against acute high intraocular pressure (HIOP).

METHODS

Acute HIPO was induced in one eye of 24 white rabbits via saline perfusion into the anterior chamber (model group), and the contralateral eye without treatment served as the control group. In another 24 rabbits, 10 microl recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-BDNF) was injected into the vitreous body of one of the eyes 3 days before the operation for HIPO (BDNF group). At 1, 3, 7, and 14 days after HIOP model establishment, 6 eyes in each group were excised to observe the number of retinal ganglion cells (RGCs) and the thickness of the inner retina layer. For the eyes dissected on day 14, electroretinogram b (ERG-b) wave was detected 30 min before (baseline) and on days 1, 3, 7 and 14 after HIOP. Another 5 rabbits were used for ultrastructural observation of the RGCs using transmission electron microscopy, including 1 without treatment, 2 with unilateral HIOP and 2 with rAAV-BDNF transfection before HIOP.

RESULTS

The amplitude of ERG-b wave showed no significant difference between the 3 groups before HIOP (P>0.05). In HIOP model group and BDNF group, the amplitude decreased to the lowest at 1 day after HIOP and failed to recover the baseline level at 14 days (P<0.01); at the end of the observation, the amplitude was significantly higher in BDNF group than in the model group (P<0.01). Decreased number of RGCs and thickness of inner retina layer occurred in the model group, but these changes were milder in BDNF group (P<0.05, P<0.01). Electron microscopy revealed ultrastructural changes in the RGCs following acute HIOP, and transfection with rAAV-BDNF ameliorated these changes.

CONCLUSION

rAAV-BDNF transfection protects the retinal structure and improves the amplitude of ERG-b wave after acute high IOP suggesting its neuroprotective effects.

Appropriateness of Treating Glaucoma Suspects RAND Study Group. For which glaucoma suspects is it appropriate to initiate treatment?

OBJECTIVE

Because uncertainty exists about which glaucoma suspects should be treated, this study sought to identify the glaucoma suspects who an expert panel could agree would be appropriate or inappropriate to treat.

DESIGN

The RAND/UCLA appropriateness method, a well-established procedure to synthesize the scientific literature with expert opinion to resolve uncertainty on a health topic.

PARTICIPANTS

Eleven-member panel composed of recognized international leaders in the field of glaucoma.

METHODS

Based on a systematic review of the literature on potentially important factors to consider when deciding to initiate treatment, more than 1000 scenarios of glaucoma suspects initially were created. The panel formally rated the appropriateness of initiating treatment for glaucoma suspects through a 2-round modified Delphi method, a technique that preserves the confidentiality of individual panelists'ratings but allows panelists to compare their own ratings with those of the entire panel.

MAIN OUTCOME MEASURES

Final ratings for scenarios were categorized as appropriate, uncertain, or inappropriate to treat according to typical prespecified statistical criteria previously used in projects using the RAND/UCLA appropriateness method. Tools were developed to help clinicians to approximate the panel ratings of glaucoma suspects.

RESULTS

The panel chose age, life expectancy, intraocular pressure (IOP), central corneal thickness, cup-to-disc ratio, disc size, and family history as the variables to consider when deciding whether to treat glaucoma suspects. Permutations of these variables created 1800 unique scenarios. The panel rated 587 (33%) scenarios as appropriate, 585 (33%) as uncertain, and 628 (35%) as inappropriate for treatment initiation. Analysis of variance determined that IOP had greater impact than any other variable on panel ratings. A point system was created with 96% sensitivity and 93% specificity for predicting panel ratings of appropriateness for a glaucoma suspect.

CONCLUSIONS

An expert panel can reach agreement on the appropriateness and inappropriateness of treatment for glaucoma suspects.

Medical costs of glaucoma and ocular hypertension in Italian referral centres: a prospective study

AIM

This study analyzes the resource utilization and costs of ocular hypertension and glaucoma (staged by severity) in Italian ophthalmology departments.

METHODS

The project was a multi-centre observational study conducted in 17 Italian ophthalmology departments throughout the country. A total of 659 patients were recruited and followed prospectively for 1 year. For the purpose of analysis, the patients were divided into 3 groups according to the severity at onset: ocular hypertension, glaucoma and advanced glaucoma.

RESULTS

The subgroups differed significantly in the main demographic and clinical variables. As expected, greater severity was associated with older mean age and worse visual acuity, and with higher resource consumption and costs. The annual average cost per patient was EUR 788.7 and rose significantly with disease severity (EUR 572.0 for ocular hypertension, EUR 734.3 for glaucoma and EUR 1,054.9 for advanced glaucoma). Drugs and specialist consultations were by far the largest cost components.

CONCLUSIONS

This study offers some information on the medical costs of glaucoma in Italy potentially useful for decision-making in the health care services. Health care resources and costs increased with disease severity.

Health care charges for patients with ocular hypertension or primary open-angle glaucoma

OBJECTIVES

To determine the total and condition-related direct health care charges of patients with ocular hypertension (OH) or primary open-angle glaucoma (POAG) and identify factors that affect these charges.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients with OH (n = 36 767) and POAG (n = 72 412) with > or =1 year of continuous enrollment during calendar years 1998 through 2005 in a nationally representative, multimanaged health plan database (PharMetrics).

METHODS

First year total health care and condition-related charges were calculated. Subsequently multivariate linear regression models determined the impact of ophthalmic condition (OH or POAG), age, index year, gender, geographic region, payer mix, product type, treatment with glaucoma medication, ocular comorbidities, and systemic comorbidities on these charges.

MAIN OUTCOME MEASURES

Per-person per year first-year total health care and ocular condition-related charges in United States dollars, adjusted for multiple covariates.

RESULTS

Patients with POAG had significantly higher adjusted total and condition-related health care charges during the first year of follow-up than patients with OH in multivariable analysis ($2070 vs. $1990, P<0.0001 and $556 vs. $322 P<0.0001, respectively). Females and older patients had higher total health care charges compared with males and younger patients ($586 or 28.3% more; P<0.0001 and $27 per year or 0.8% per year more; P<0.0001, respectively). However, neither gender nor age were strong determinants of condition-related charges (P = 0.13 and P = 0.052, respectively). Index year, region, payer, and product types significantly dictated both total and disease-related charges. Patients with ocular comorbid conditions, including cataracts, cataract surgery, diabetic retinopathy, and blindness, had significantly higher total and condition-related health care charges than patients without these conditions (P<0.0001).

CONCLUSION

Total and condition-related health care charges are considerable for patients with OH and POAG. These data identify several factors that dictate these charges.

Canadian perspectives in glaucoma management: the role of central corneal thickness

BACKGROUND

To propose consensus working recommendations for the role of central corneal thickness in the management of open-angle glaucoma.

METHODS

This work is based on evidence from a review of the glaucoma literature, a Canadian consensus development workshop, and the personal clinical experience of the participating Canadian ophthalmologists.

RESULTS

Guidelines were developed to provide eye care practitioners and their patients with support in the decision-making process for management of glaucoma or those at risk for developing glaucoma.

INTERPRETATION

Further studies will be helpful in understanding the role of central corneal thickness in glaucoma management, and these guidelines will need to be revised periodically as new information becomes available.

Cost-effective evaluation of the glaucoma suspect

PURPOSE OF REVIEW

The number of glaucoma patients nationwide will increase appreciably over the coming years reflecting the increased number of elderly people. This increase will require efficient allocation of available healthcare resources for management of the entire spectrum of disease from glaucoma suspect to advanced glaucoma. This review considers the cost-effective management of glaucoma suspects.

RECENT FINDINGS

Medications account for the majority of costs of managing glaucoma suspects while the cost of clinical evaluations has remained stable. Early disease recognition limits both direct and indirect costs. Risk stratification of glaucoma suspects can identify those who would benefit most from therapy. Newer structural modalities can be as predictive of early disease progression as stereo disk photography. Short-wavelength automated perimetry and frequency doubling technology may be more appropriate in confirming field changes in this patient population.

SUMMARY

Overall costs of managing glaucoma can be limited by preventing early disease progression. Identification and monitoring of glaucoma suspects would help minimize overall costs if intraocular pressure lowering therapy is reserved for high-risk glaucoma suspects or those with early disease. Yet, since the rate of progression to blindness for a particular patient is not known, the most cost-effective time to begin intraocular pressure lowering therapy remains unclear.