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Frontiers in Neurology 2017Multiple system atrophy (MSA) is a rare, adult-onset, rapidly progressive fatal synucleinopathy that primarily affects oligodendroglial cells in the brain. Patients with... (Review)
Review
BACKGROUND
Multiple system atrophy (MSA) is a rare, adult-onset, rapidly progressive fatal synucleinopathy that primarily affects oligodendroglial cells in the brain. Patients with MSA only rarely have visual complaints, but recent studies of the retina using optical coherence tomography (OCT) showed atrophy of the peripapillary retinal nerve fiber layer (RNFL) and to a lesser extent the macular ganglion cell layer (GCL) complex.
METHODS
We performed a literature review and meta-analysis according to the preferred reporting items for systematic reviews and meta-analyses guidelines for studies published before January 2017, identified through PubMed and databases, which reported OCT-related outcomes in patients with MSA and controls. A random-effects model was constructed.
RESULTS
The meta-analysis search strategy yielded 15 articles of which 7 met the inclusion criteria. The pooled difference in the average thickness of the RNFL was -5.48 μm (95% CI, -6.23 to -4.73; < 0.0001), indicating significant thinning in patients with MSA. The pooled results showed significant thinning in all the specific RNFL quadrants, except in the temporal RNFL quadrant, where the thickness in MSA and controls was similar [pooled difference of 1.11 µm (95% CI, -4.03 to 6.26; = 0.67)]. This pattern of retinal damage suggests that MSA patients have preferential loss of retinal ganglion cells projecting to the magnocellular pathway (M-cells), which are mainly located in the peripheral retina and are not essential for visual acuity. Visual acuity, on the other hand, relies mostly on macular ganglion cells projecting to the parvocellular pathway (P-cells) through the temporal portion of the RNFL, which are relatively spared in MSA patients.
CONCLUSION
The retinal damage in patients with MSA differs from that observed in patients with Parkinson disease (PD). Patients with MSA have more relative preservation of temporal sector of the RNFL and less severe atrophy of the macular GCL complex. We hypothesize that in patients with MSA there is predominant damage of large myelinated optic nerve axons like those originating from the M-cells. These large axons may require higher support from oligodendrocytes. Conversely, in patients with PD, P-cells might be more affected.
PubMed: 28596752
DOI: 10.3389/fneur.2017.00206 -
The Cochrane Database of Systematic... Jan 2017Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells, and ultimately visual field... (Review)
Review
BACKGROUND
Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells, and ultimately visual field loss. It is a leading cause of blindness worldwide. Open angle glaucoma (OAG), the most common form of glaucoma, is a chronic condition that may or may not present with increased intraocular pressure (IOP). Neuroprotection for glaucoma refers to any intervention intended to prevent optic nerve damage or cell death.
OBJECTIVES
The objective of this review was to systematically examine the evidence regarding the effectiveness of neuroprotective agents for slowing the progression of OAG in adults compared with no neuroprotective agent, placebo, or other glaucoma treatment.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 7), Ovid MEDLINE, Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Ovid MEDLINE Daily (January 1946 to August 2016), Embase (January 1980 to August 2016), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to August 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 16 August 2016.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) in which topical or oral treatments were used for neuroprotection in adults with OAG. Minimum follow-up time was four years.
DATA COLLECTION AND ANALYSIS
Two review authors independently reviewed titles and abstracts from the literature searches. We obtained full-text copies of potentially relevant studies and re-evaluated for inclusion. Two review authors independently extracted data related to study characteristics, risk of bias, and outcomes. We identified one trial for this review, thus we performed no meta-analysis. Two studies comparing memantine to placebo are currently awaiting classification until study investigators provide additional study details. We documented reasons for excluding studies from the review.
MAIN RESULTS
We included one multicenter RCT of adults with low-pressure glaucoma (Low-pressure Glaucoma Treatment Study, LoGTS) conducted in the USA. The primary outcome was progression of visual field loss after four years of treatment with either brimonidine or timolol. Of the 190 adults enrolled in the study, the investigators excluded 12 (6.3%) after randomization; 77 participants (40.5%) did not complete four years of follow-up. The rate of attrition was unbalanced between groups with more participants dropping out of the brimonidine group (55%) than the timolol group (29%).Of those remaining in the study at four years, participants assigned to brimonidine showed less progression of visual field loss than participants assigned to timolol (risk ratio (RR) 0.35, 95% confidence interval (CI) 0.14 to 0.86; 101 participants). Because of high risk of attrition bias and potential selective outcome reporting, we graded the certainty of evidence for this outcome as very low. At the four-year follow-up, the mean IOP was similar in both groups among those for whom data were available (mean difference 0.20 mmHg, 95% CI -0.73 to 1.13; 91 participants; very low-certainty evidence). The study authors did not report analyzable data for visual acuity or any data related to vertical cup-disc ratio, quality of life, or economic outcomes. The most frequent adverse event was ocular allergy to the study drug, which affected more participants in the brimonidine group than the timolol group (RR 5.32, 95% CI 1.64 to 17.26; 178 participants; very low-certainty evidence).
AUTHORS' CONCLUSIONS
Although the only trial we included in this review found less visual field loss in the brimonidine-treated group, the evidence was of such low certainty that we can draw no conclusions from this finding. Further clinical research is needed to determine whether neuroprotective agents may be beneficial for individuals with OAG. Such research should focus on outcomes important to patients, such as preservation of vision, and how these outcomes relate to cell death and optic nerve damage. As OAG is a chronic, progressive disease with variability in symptoms, RCTs designed to measure the effectiveness of neuroprotective agents require a long-term follow-up of five years or longer to detect clinically meaningful effects.
Topics: Adult; Antihypertensive Agents; Brimonidine Tartrate; Disease Progression; Glaucoma, Open-Angle; Humans; Neuroprotective Agents; Optic Nerve; Optic Nerve Diseases; Randomized Controlled Trials as Topic; Retinal Ganglion Cells; Timolol
PubMed: 28122126
DOI: 10.1002/14651858.CD006539.pub4 -
Eye (London, England) Feb 2017Blindness afflicts ~39 million people worldwide. Retinal ganglion cells are unable to regenerate, making this condition irreversible in many cases. Whole-eye... (Review)
Review
Blindness afflicts ~39 million people worldwide. Retinal ganglion cells are unable to regenerate, making this condition irreversible in many cases. Whole-eye transplantation (WET) provides the opportunity to replace diseased retinal ganglion cells, as well as the entire optical system and surrounding facial tissue, if necessary. Recent success in face transplantation demonstrates that this may be a promising treatment for what has been to this time an incurable condition. An animal model for WET must be established to further enhance our knowledge of nerve regeneration, immunosuppression, and technical aspects of surgery. A systematic review of the literature was performed to evaluate studies describing animal models for WET. Only articles in which the eye was completely enucleated and reimplanted were included. Study methods and results were compared. In the majority of published literature, WET can result in recovery of vision in cold-blooded vertebrates. There are a few instances in which mammalian WET models demonstrate survival of the transplanted tissue following neurovascular anastomosis and the ability to maintain brief electroretinogram activity in the new host. In this study we review in cold-blooded vertebrates and mammalian animal models for WET and discuss prospects for future research for translation to human eye transplantation.
Topics: Animals; Blindness; Disease Models, Animal; Eye; Optic Nerve Injuries; Organ Transplantation; Retina; Tissue Survival
PubMed: 27983731
DOI: 10.1038/eye.2016.272 -
The Cochrane Database of Systematic... Feb 2016Glaucoma is a chronic optic neuropathy characterized by retinal ganglion cell death resulting in damage to the optic nerve head and the retinal nerve fiber layer.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Glaucoma is a chronic optic neuropathy characterized by retinal ganglion cell death resulting in damage to the optic nerve head and the retinal nerve fiber layer. Pigment dispersion syndrome is characterized by a structural disturbance in the iris pigment epithelium (the densely pigmented posterior surface of the iris) that leads to dispersion of the pigment and its deposition on various structures within the eye. Pigmentary glaucoma is a specific form of open-angle glaucoma found in patients with pigment dispersion syndrome.Topcial medical therapy is usually the first-line treatment; however, peripheral laser iridotomy has been proposed as an alternate treatment. Peripheral laser iridotomy involves creating an opening in the iris tissue to allow drainage of fluid from the posterior chamber to the anterior chamber and vice versa. Equalizing the pressure within the eye may help to alleviate the friction that leads to pigment dispersion and prevent visual field deterioration. However, the effectiveness of peripheral laser iridotomy in reducing the development or progression of pigmentary glaucoma is unknown.
OBJECTIVES
The objective of this review was to assess the effects of peripheral laser iridotomy compared with other interventions, including medication, trabeculoplasty, and trabeculectomy, or no treatment, for pigment dispersion syndrome and pigmentary glaucoma.
SEARCH METHODS
We searched a number of electronic databases including CENTRAL, MEDLINE and EMBASE and clinical trials websites such as (mRCT) and ClinicalTrials.gov. We last searched the electronic databases on 2 November 2015.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) that had compared peripheral laser iridotomy versus no treatment or other treatments for pigment dispersion syndrome and pigmentary glaucoma.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures for systematic reviews. Two review authors independently screened articles for eligibility, extracted data, and assessed included trials for risk of bias. We did not perform a meta-analysis because of variability in reporting and follow-up intervals for primary and secondary outcomes of interest.
MAIN RESULTS
We included five RCTs (260 eyes of 195 participants) comparing yttrium-aluminum-garnet (YAG) laser iridotomy versus no laser iridotomy. Three trials included participants with pigmentary glaucoma at baseline, and two trials enrolled participants with pigment dispersion syndrome. Only two trials reported the country of enrollment: one - Italy, the other - United Kingdom. Overall, we assessed trials as having high or unclear risk of bias owing to incomplete or missing data and selective outcome reporting.Data on visual fields were available for one of three trials that included participants with pigmentary glaucoma at baseline. At an average follow-up of 28 months, the risk of progression of visual field damage was uncertain when comparing laser iridotomy with no iridotomy (risk ratio (RR) 1.00, 95% confidence interval (95% CI) 0.16 to 6.25; 32 eyes; very low-quality evidence). The two trials that enrolled participants with pigment dispersion syndrome at baseline reported the proportion of participants with onset of glaucomatous visual field changes during the study period. At three-year follow-up, one trial reported that the risk ratio for conversion to glaucoma was 2.72 (95% CI 0.76 to 9.68; 42 eyes; very low-quality evidence). At 10-year follow-up, the other trial reported that no eye showed visual field progression.One trial reported the mean change in intraocular pressure (IOP) in eyes with pigmentary glaucoma: At an average of nine months of follow-up, the mean difference in IOP between groups was 2.69 mmHg less in the laser iridotomy group than in the control group (95% CI -6.05 to 0.67; 14 eyes; very low-quality evidence). This trial also reported the mean change in anterior chamber depth at an average of nine months of follow-up and reported no meaningful differences between groups (mean difference 0.04 mm, 95% CI -0.07 to 0.15; 14 eyes; very low-quality evidence). No other trial reported mean change in anterior chamber depth. Two trials reported greater flattening of iris configuration in the laser iridotomy group than in the control group among eyes with pigmentary glaucoma; however, investigators provided insufficient data for analysis. No trial reported data related to mean visual acuity, aqueous melanin granules, costs, or quality of life outcomes.Two trials assessed the need for additional treatment for control of IOP. One trial that enrolled participants with pigmentary glaucoma reported that more eyes in the laser iridotomy group required additional treatment between six and 23 months of follow-up than eyes in the control group (RR 1.73, 95% CI 1.08 to 2.75; 46 eyes); however, the other trial enrolled participants with pigment dispersion syndrome and indicated that the difference between groups at three-year follow-up was uncertain (RR 0.91, 95% CI 0.38 to 2.17; 105 eyes). We graded the certainty of evidence for this outcome as very low.Two trials reported that no serious adverse events were observed in either group among eyes with pigment dispersion syndrome. Mild adverse events included postoperative inflammation; two participants required cataract surgery (at 18 and 34 months after baseline), and two participants required a repeat iridotomy.
AUTHORS' CONCLUSIONS
We found insufficient evidence of high quality on the effectiveness of peripheral iridotomy for pigmentary glaucoma or pigment dispersion syndrome. Although adverse events associated with peripheral iridotomy may be minimal, the long-term effects on visual function and other patient-important outcomes have not been established. Future research on this topic should focus on outcomes that are important to patients and the optimal timing of treatment in the disease process (eg, pigment dispersion syndrome with normal IOP, pigment dispersion syndrome with established ocular hypertension, pigmentary glaucoma).
Topics: Aluminum; Antihypertensive Agents; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Iris; Laser Therapy; Ophthalmologic Surgical Procedures; Randomized Controlled Trials as Topic; Visual Acuity; Yttrium
PubMed: 26871761
DOI: 10.1002/14651858.CD005655.pub2 -
BioMed Research International 2015Glaucoma is a multifactorial disease that is the leading cause of irreversible blindness. Recent data documented that glaucoma is not limited to the retinal ganglion... (Review)
Review
Glaucoma is a multifactorial disease that is the leading cause of irreversible blindness. Recent data documented that glaucoma is not limited to the retinal ganglion cells but that it also extends to the posterior visual pathway. The diagnosis is based on the presence of signs of glaucomatous optic neuropathy and consistent functional visual field alterations. Unfortunately these functional alterations often become evident when a significant amount of the nerve fibers that compose the optic nerve has been irreversibly lost. Advanced morphological and functional magnetic resonance (MR) techniques (morphometry, diffusion tensor imaging, arterial spin labeling, and functional connectivity) may provide a means for observing modifications induced by this fiber loss, within the optic nerve and the visual cortex, in an earlier stage. The aim of this systematic review was to determine if the use of these advanced MR techniques could offer the possibility of diagnosing glaucoma at an earlier stage than that currently possible.
Topics: Diagnostic Techniques, Ophthalmological; Glaucoma; Humans; Magnetic Resonance Imaging
PubMed: 26167474
DOI: 10.1155/2015/160454 -
The Cochrane Database of Systematic... Jun 2013Traumatic optic neuropathy (TON) is an important cause of severe visual loss following blunt or penetrating head trauma. Following the initial insult optic nerve... (Review)
Review
BACKGROUND
Traumatic optic neuropathy (TON) is an important cause of severe visual loss following blunt or penetrating head trauma. Following the initial insult optic nerve swelling within the optic nerve canal or compression by bone fragments are thought to result in secondary retinal ganglion cell loss. Optic nerve decompression with steroids or surgical interventions or both have therefore been advocated to improve visual prognosis in TON.
OBJECTIVES
To examine the effects and safety of surgical interventions in the management of TON.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to May 2013), EMBASE (January 1980 to May 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to May 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (http://clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 28 May 2013. We also searched the reference lists of other reviews and book chapters on TON. We also contacted researchers in the field.
SELECTION CRITERIA
We planned to include only randomised controlled trials (RCTs) of TON in which any form of surgical intervention either on its own or in combination with steroids was compared to steroids alone or no treatment.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed the titles and abstracts identified from the search strategy. No studies were found that met our inclusion criteria and therefore none were included for analysis.
MAIN RESULTS
No studies were found that met our inclusion criteria.
AUTHORS' CONCLUSIONS
The current body of evidence consists mostly of small, retrospective case series. Given the wide range of surgical interventions used in TON it is very difficult to compare these studies, even qualitatively. However, there is a relatively high rate of spontaneous visual recovery and no evidence that surgical decompression of the optic nerve provides any additional benefit. On the other hand, surgery carries a definite risk of complications such as postoperative cerebrospinal fluid leak and meningitis. The decision to proceed with surgery in TON therefore remains controversial and each case needs to be assessed on its own merits. Although there is an urgent need for an adequately powered, RCT of surgical intervention in TON, this will prove a difficult endeavour.
Topics: Humans; Optic Nerve Injuries
PubMed: 23780732
DOI: 10.1002/14651858.CD005024.pub3 -
The Cochrane Database of Systematic... Jun 2013Traumatic optic neuropathy (TON) is an important cause of severe visual loss following blunt or penetrating head trauma. Following the initial injury, optic nerve... (Review)
Review
BACKGROUND
Traumatic optic neuropathy (TON) is an important cause of severe visual loss following blunt or penetrating head trauma. Following the initial injury, optic nerve swelling within the optic nerve canal can result in secondary retinal ganglion cell loss. Optic nerve decompression with steroids or surgical interventions or both has therefore been advocated as a means of improving visual prognosis in TON.
OBJECTIVES
The aim of this review was to examine the effectiveness and safety of using steroids in TON.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to May 2013), EMBASE (January 1980 to May 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to May 2013), Web of Science Conference Proceedings Citation Index- Science (CPCI-S) (January 1990 to May 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (http://clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 21 May 2013. We also searched the reference lists of included studies, other reviews and book chapters on TON to find references to additional trials. The Science Citation Index was used to look for papers that cited the studies included in this review. We did not manually search any journals or conference proceedings. We contacted trial investigators and experts in the field to identify additional published and unpublished studies.
SELECTION CRITERIA
We planned to include only randomised controlled trials (RCTs) of TON in which any steroid regime, either on its own or in combination with surgical optic nerve decompression, was compared to surgery alone or no treatment.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed the titles and abstracts identified from the electronic searches.
MAIN RESULTS
We included one study that met our selection criteria; a double-masked, placebo-controlled, randomised trial of high dose intravenous steroids in patients with indirect TON diagnosed within seven days of the initial injury. A total of 31 eligible participants were randomised to receive either high dose intravenous steroids (n = 16) or placebo (n = 15), and they were all followed-up for three months. Mean final best corrected visual acuity (BCVA) was 1.78±1.23 Logarithm of the Minimum Angle of Resolution (LogMAR) in the placebo group, and 1.11±1.14 LogMAR in the steroid group. The mean difference in BCVA between the placebo and steroid groups was 0.67 LogMAR (95% confidence interval -1.54 to 0.20), and this difference was not statistically significant (P = 0.13). At three months follow-up, an improvement in BCVA of 0.40 LogMAR occurred in eight eyes (8/15, 53.3%) in the placebo group, and in 11 eyes (11/16, 68.8%) in the treatment group. This difference was not statistically significant (P = 0.38).
AUTHORS' CONCLUSIONS
There is a relatively high rate of spontaneous visual recovery in TON and there is no convincing data that steroids provide any additional visual benefit over observation alone. Recent evidence also suggests a possible detrimental effect of steroids in TON and further studies are urgently needed to clarify this important issue. Each case therefore needs to be assessed on an individual basis and proper informed consent is paramount.
Topics: Humans; Injections, Intravenous; Methylprednisolone; Optic Nerve Injuries; Randomized Controlled Trials as Topic; Steroids; Visual Acuity
PubMed: 23771729
DOI: 10.1002/14651858.CD006032.pub4 -
The Cochrane Database of Systematic... May 2013Glaucoma is a multifactorial optic neuropathy characterized by an acquired loss of retinal ganglion cells at levels beyond normal age-related loss and corresponding... (Review)
Review
BACKGROUND
Glaucoma is a multifactorial optic neuropathy characterized by an acquired loss of retinal ganglion cells at levels beyond normal age-related loss and corresponding atrophy of the optic nerve. Although many treatments are available to manage glaucoma, glaucoma is a chronic condition. Some patients may seek complementary or alternative medicine approaches such as acupuncture to supplement their regular treatment. The underlying plausibility of acupuncture is that disorders related to the flow of Chi (the traditional Chinese concept translated as vital force or energy) can be prevented or treated by stimulating relevant points on the body surface.
OBJECTIVES
The objective of this review was to assess the effectiveness and safety of acupuncture in people with glaucoma.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2013), EMBASE (January 1980 to January 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2013), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (January 1937 to January 2013), ZETOC (January 1993 to January 2013), Allied and Complementary Medicine Database (AMED) (January 1985 to January 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) and the National Center for Complementary and Alternative Medicine web site (NCCAM) (http://nccam.nih.gov). We did not use any language or date restrictions in the search for trials. We last searched the electronic databases on 8 January 2013 with the exception of NCCAM which was last searched on 14 July 2010. We also handsearched Chinese medical journals at Peking Union Medical College Library in April 2007.We searched the Chinese Acupuncture Trials Register, the Traditional Chinese Medical Literature Analysis and Retrieval System (TCMLARS), and the Chinese Biological Database (CBM) for the original review; we did not search these databases for the 2013 review update.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) in which one arm of the study involved acupuncture treatment.
DATA COLLECTION AND ANALYSIS
Two authors independently evaluated the search results and then full text articles against the eligibility criteria. We resolved discrepancies by discussion.
MAIN RESULTS
We included one completed and one ongoing trial, and recorded seven trials awaiting assessment for eligibility. These seven trials were written in Chinese and were identified from a systematic review on the same topic published in a Chinese journal. The completed trial compared auricular acupressure-a nonstandard acupuncture technique-with the sham procedure for glaucoma. This trial is rated at high risk of bias for masking of outcome assessors, unclear risk of bias for selective outcome reporting, and low risk of bias for other domains. The difference in intraocular pressure (measured in mm Hg) in the acupressure group was significantly less than that in the sham group at four weeks (-3.70, 95% confidence interval [CI] -7.11 to -0.29 for the right eye; -4.90, 95% CI -8.08 to -1.72 for the left eye), but was not statistically different at any other follow-up time points, including the longest follow-up time at eight weeks. No statistically significant difference in visual acuity was noted at any follow-up time points. The ongoing trial was registered with the International Clinical Trials Registry Platform (ICTRP) of the World Health Organization. To date this trial has not recruited any participants.
AUTHORS' CONCLUSIONS
At this time, it is impossible to draw reliable conclusions from available data to support the use of acupuncture for the treatment of glaucoma. Because of ethical considerations, RCTs comparing acupuncture alone with standard glaucoma treatment or placebo are unlikely to be justified in countries where the standard of care has already been established. Because most glaucoma patients currently cared for by ophthalmologists do not use nontraditional therapy, clinical practice decisions will have to be based on physician judgments and patient preferences, given this lack of data in the literature. Inclusion of the seven Chinese trials in future updates of this review may change our conclusions.
Topics: Acupuncture Therapy; Acupuncture, Ear; Glaucoma; Humans; Randomized Controlled Trials as Topic
PubMed: 23728656
DOI: 10.1002/14651858.CD006030.pub3 -
The Cochrane Database of Systematic... Feb 2013Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells and ultimately visual field... (Review)
Review
BACKGROUND
Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells and ultimately visual field loss. It is a leading cause of blindness worldwide. Open angle glaucoma (OAG), the commonest form of glaucoma, is a chronic condition that may or may not present with increased intraocular pressure (IOP). Neuroprotection for glaucoma refers to any intervention intended to prevent optic nerve damage or cell death.
OBJECTIVES
The objective of this review was to systematically examine the evidence regarding the effectiveness of neuroprotective agents for slowing the progression of OAG in adults.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to October 2012), EMBASE (January 1980 to October 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to October 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 16 October 2012.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) in which topical or oral treatments were used for neuroprotection in adults with OAG. Minimum follow up time was four years.
DATA COLLECTION AND ANALYSIS
Two review authors independently reviewed titles and abstracts from the literature searches. Full-text copies of potentially relevant studies were obtained and re-evaluated for inclusion. Two review authors independently extracted data related study characteristics, risk of bias, and outcome data. One trial was identified for this review, thus we performed no meta-analysis. Two studies comparing memantine to placebo are currently awaiting classification until additional study details are provided. We documented reasons for excluding studies from the review.
MAIN RESULTS
We included one multi-center RCT of adults with low-pressure glaucoma (Low-pressure Glaucoma Treatment Study, LoGTS) conducted in the USA. The primary outcome was visual field progression after four years of treatment with either brimonidine or timolol. Of the 190 adults enrolled in the study, 12 (6.3%) were excluded after randomization and 77 (40.5%) did not complete four years of follow up. The rate of attrition was unbalanced between groups with more participants dropping out of the brimonidine group (55%) than the timolol group (29%). Of those remaining in the study at four years, participants assigned to brimonidine showed less visual field progression than participants assigned to timolol (5/45 participants in the brimonidine group compared with 18/56 participants in the timolol group). Since no information was available for the 12 participants excluded from the study, or the 77 participants who dropped out of the study, we cannot draw any conclusions from these results as the participants for whom data are missing may or may not have progressed. The mean IOP was similar in both groups at the four-year follow up among those for whom data were available: 14.2 mmHg (standard deviation (SD) = 1.9) among the 43 participants in the brimonidine group and 14.0 mmHg (SD = 2.6) among the 48 participants in the timolol group. Among the participants who developed progressive visual field loss, IOP reduction of 20% or greater was not significantly different between groups: 4/9 participants in the brimonidine group and 12/31 participants in the timolol group. The study authors did not report data for visual acuity or vertical cup-disc ratio. The most frequent adverse event was ocular allergy to study drug, which occurred more frequently in the brimonidine group (20/99 participants) than the timolol group (3/79 participants).
AUTHORS' CONCLUSIONS
Although neuroprotective agents are intended to act as pharmacological antagonists to prevent cell death, this trial did not provide evidence that they are effective in preventing retinal ganglion cell death, and thus preserving vision in people with OAG. Further clinical research is needed to determine whether neuroprotective agents may be beneficial for individuals with OAG. Such research should focus outcomes important to patients, such as preservation of vision, and how these outcomes relate to cell death and optic nerve damage. Since OAG is a chronic, progressive disease with variability in symptoms, RCTs designed to measure the effectiveness of neuroprotective agents would require long-term follow up (more than four years) in order to detect clinically meaningful effects.
Topics: Adult; Antihypertensive Agents; Brimonidine Tartrate; Disease Progression; Glaucoma, Open-Angle; Humans; Neuroprotective Agents; Optic Nerve; Optic Nerve Diseases; Quinoxalines; Randomized Controlled Trials as Topic; Retinal Ganglion Cells; Timolol
PubMed: 23450569
DOI: 10.1002/14651858.CD006539.pub3 -
The Cochrane Database of Systematic... Feb 2010Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells and ultimately visual field... (Review)
Review
BACKGROUND
Glaucoma is a heterogeneous group of conditions involving progressive damage to the optic nerve, deterioration of retinal ganglion cells and ultimately visual field loss. It is a leading cause of blindness worldwide. Open angle glaucoma (OAG), the commonest form of glaucoma, is a chronic condition that may or may not present with increased intraocular pressure (IOP). Neuroprotection for glaucoma refers to any intervention intended to prevent optic nerve damage or cell death. The treatment can target extracellular factors such as reducing IOP, or cellular factors derived from the optic nerve itself such as blocking intracellular death signals.
OBJECTIVES
The objective of this review was to systematically examine the evidence regarding the effectiveness of neuroprotective agents, either topical or oral, for slowing the progression of OAG in adults.
SEARCH STRATEGY
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library, Issue 4, 2009), MEDLINE (January 1960 to January 2010), EMBASE (January 1980 to January 2010), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2010) and ClinicalTrials.gov (http://clinicaltrials.gov). (5 January 2010). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 5 January 2010.
SELECTION CRITERIA
This review was limited to randomized controlled trials (RCTs) in which topical or oral treatments were used to prevent retinal ganglion cell death. Our population of interest was adults with OAG. As the primary outcome for this review was the proportion of participants who developed any progression of visual field loss at five years post intervention, only trials with at least five years of follow-up were included.
DATA COLLECTION AND ANALYSIS
Two review authors independently reviewed titles and abstracts from the literature searches. Full text copies of relevant or potentially relevant studies were obtained and re-evaluated for inclusion. There were no trials identified for this review, thus we performed no data extraction or meta-analysis. Two studies comparing memantine to placebo are currently awaiting classification until additional study details are provided. Reasons for excluding studies from the review were documented.
MAIN RESULTS
In accordance with the selection criteria for inclusion, we identified no studies relevant for this review. The results of short-term trials and other studies are discussed in this review.
AUTHORS' CONCLUSIONS
Although neuroprotective agents are intended to act as pharmacological antagonists to prevent cell death, the evidence that they are effective in preventing retinal ganglion cell death, and thus preserving vision in patients with OAG, has not been demonstrated. Long-term RCTs are needed to determine whether or not neuroprotective agents may be beneficial for individuals with OAG.
Topics: Administration, Oral; Administration, Topical; Adult; Cell Death; Disease Progression; Glaucoma, Open-Angle; Humans; Neuroprotective Agents; Optic Nerve; Optic Nerve Diseases; Retinal Ganglion Cells
PubMed: 20166085
DOI: 10.1002/14651858.CD006539.pub2