- •PROGRESS IN BRAIN RESEARCH
- •List of Contributors
- •Preface
- •Epidemiology of primary glaucoma: prevalence, incidence, and blinding effects
- •Introduction
- •Prevalence of glaucoma
- •PAC suspect
- •PACG
- •Incidence of glaucoma
- •Blinding effects of glaucoma
- •Abbreviations
- •Acknowledgment
- •References
- •Predictive models to estimate the risk of glaucoma development and progression
- •Risk assessment in ocular hypertension and glaucoma
- •Risk factors for glaucoma development
- •Intraocular pressure
- •Corneal thickness
- •Cup/disc ratio and pattern standard deviation
- •The need for predictive models
- •Predictive models for glaucoma development
- •Predictive models for glaucoma progression
- •Limitations of predictive models
- •References
- •Intraocular pressure and central corneal thickness
- •Main text
- •References
- •Angle-closure: risk factors, diagnosis and treatment
- •Introduction
- •Mechanism
- •Other causes of angle closure
- •Risk factors
- •Age and gender
- •Ethnicity
- •Ocular biometry
- •Genetics
- •Diagnosis
- •Acute primary angle closure
- •Angle assessment in angle closure
- •Gonioscopy technique
- •Ultrasound biomicroscopy (UBM)
- •Scanning peripheral anterior chamber depth analyzer (SPAC)
- •Management
- •Acute primary angle closure
- •Medical therapy
- •Argon laser peripheral iridoplasty (ALPI)
- •Laser peripheral iridotomy (PI)
- •Lens extraction
- •Monitoring for subsequent IOP rise in eyes with APAC
- •Fellow eye of APAC
- •Chronic primary angle-closure glaucoma (CACG)
- •Laser peripheral iridotomy
- •Laser iridoplasty
- •Medical therapy
- •Trabeculectomy
- •Lens extraction
- •Combined lens extraction and trabeculectomy surgery
- •Goniosynechialysis
- •Summary
- •List of abbreviations
- •References
- •Early diagnosis in glaucoma
- •Introduction
- •History and examination
- •Quantitative tests and the diagnostic process
- •Pretest probability
- •Test validity
- •Diagnostic test performance
- •Posttest probability
- •Combing test results
- •Selective tests of visual function
- •Early glaucoma diagnosis from quantitative test results
- •Progression to make a diagnosis
- •Conclusions
- •Abbreviations
- •References
- •Monitoring glaucoma progression
- •Introduction
- •Monitoring structural damage progression
- •Monitoring functional damage progression
- •Abbreviations
- •References
- •Standard automated perimetry and algorithms for monitoring glaucoma progression
- •Standard automated perimetry
- •Global indices
- •HFA: MD, SF, PSD, CPSD
- •Octopus indices: MD, SF, CLV
- •OCTOPUS seven-in-one report (Fig. 2)
- •SAP VF assessment: full-threshold strategy
- •SAP VF defects assessment: OHTS criteria
- •SAP VF defects assessment: AGIS criteria
- •SAP VF defects assessment: CIGTS
- •Fastpac
- •Swedish interactive threshold algorithm
- •SAP VF assessment: the glaucoma staging system
- •SAP: interocular asymmetries in OHTS
- •SAP, VF progression
- •SAP: the relationship to other functional and structural diagnostic tests in glaucoma
- •SAP, FDP-Matrix
- •SAP, SWAP, HPRP, FDT
- •SAP: the relationship between function and structure
- •SAP, confocal scanning laser ophthalmoscopy, SLP-VCC
- •SAP, optical coherence tomography
- •SAP and functional magnetic resonance imaging
- •References
- •Introduction
- •Retinal ganglion cells: anatomy and function
- •Is glaucoma damage selective for any subgroup of RGCs?
- •Segregation
- •Isolation
- •FDT: rationale and perimetric techniques
- •SWAP: rationale and perimetric techniques
- •FDT: clinical data
- •SWAP: clinical data
- •Clinical data comparing FDT and SWAP
- •Conclusions
- •References
- •Scanning laser polarimetry and confocal scanning laser ophthalmoscopy: technical notes on their use in glaucoma
- •The GDx scanning laser polarimeter
- •Serial analysis
- •Limits
- •The Heidelberg retinal tomograph
- •Limits
- •Conclusions
- •References
- •The role of OCT in glaucoma management
- •Introduction
- •How OCT works
- •How OCT is performed
- •Evaluation of RNFL thickness
- •Evaluation of optic disc
- •OCT in glaucoma management
- •New perspective
- •Abbreviations
- •References
- •Introduction
- •Technology
- •Visual stimulation
- •Reproducibility and habituation of RFonh
- •Retinal neural activity as assessed from the electroretinogram (ERG)
- •The Parvo (P)- and Magno (M)-cellular pathways
- •Physiology
- •Magnitude and time course of RFonh in humans
- •Varying the parameters of the stimulus on RFonh
- •Luminance versus chromatic modulation
- •Frequency
- •Effect of pattern stimulation
- •Neurovascular coupling in humans
- •Clinical application
- •RFonh in OHT and glaucoma patients
- •Discussion
- •FLDF and neurovascular coupling in humans
- •Comments on clinical application of FLDF in glaucoma
- •Conclusions and futures directions
- •Acknowledgements
- •References
- •Advances in neuroimaging of the visual pathways and their use in glaucoma
- •Introduction
- •Conventional MR imaging and the visual pathways
- •Diffusion MR imaging
- •Functional MR imaging
- •Proton MR spectroscopy
- •References
- •Primary open angle glaucoma: an overview on medical therapy
- •Introduction
- •When to treat
- •Whom to treat
- •Genetics
- •Race
- •Ocular and systemic abnormalities
- •Tonometry and pachymetry
- •How to treat
- •Beta-blockers
- •Prostaglandins
- •Alpha-agonists
- •Carbonic anhydrase inhibitors (CAIs)
- •Myotics
- •Fixed combinations
- •References
- •The treatment of normal-tension glaucoma
- •Introduction
- •Epidemiology
- •Clinical features
- •Optic disk
- •Central corneal thickness
- •Disease course
- •Risk factors
- •Intraocular pressure
- •Local vascular factors
- •Immune mechanisms
- •Differential diagnosis
- •Diagnostic evaluation
- •Therapy
- •IOP reduction
- •Systemic medications
- •Neuroprotection
- •Noncompliance
- •Genetics of NTG
- •Abbreviations
- •References
- •The management of exfoliative glaucoma
- •Introduction
- •Epidemiology
- •Ocular and systemic associations
- •Ocular associations
- •Systemic associations
- •Pathogenesis of exfoliation syndrome
- •Mechanisms of glaucoma development
- •Management
- •Medical therapy
- •Laser surgery
- •Operative surgery
- •Future treatment of exfoliation syndrome and exfoliative glaucoma
- •Treatment directed at exfoliation material
- •References
- •Laser therapies for glaucoma: new frontiers
- •Background
- •Laser iridotomy
- •Indications
- •Contraindications
- •Patient preparation
- •Technique
- •Nd:YAG laser iridectomy
- •Argon laser iridectomy
- •Complications
- •LASER trabeculoplasty
- •Treatment technique
- •Mechanism of action
- •Indications for treatment
- •Contraindications to treatment
- •Patient preparation and postoperative follow-up
- •Complications of the treatment
- •Selective laser trabeculoplasty
- •Results
- •LASER iridoplasty
- •Indications
- •Contraindications
- •Treatment technique
- •Complications
- •LASER cyclophotocoagulation
- •Introduction
- •Indications and contraindications
- •Patient preparation
- •Transpupillary cyclophotocoagulation
- •Endoscopic cyclophotocoagulation
- •Transscleral cyclophotocoagulation
- •Transscleral noncontact cyclophotocoagulation
- •Transscleral contact cyclophotocoagulation
- •Complications
- •Excimer laser trabeculotomy
- •References
- •Modulation of wound healing during and after glaucoma surgery
- •The process of wound healing
- •Using surgical and anatomical principles to modify therapy
- •Growth factors
- •Cellular proliferation and vascularization
- •Cell motility, matrix contraction and synthesis
- •Drug delivery
- •Future directions: total scarring control and tissue regeneration
- •Acknowledgments
- •References
- •Surgical alternative to trabeculectomy
- •Introduction
- •Deep sclerectomy
- •Viscocanalostomy
- •Conclusions
- •References
- •Modern aqueous shunt implantation: future challenges
- •Background
- •Current shunts and factors affecting their function
- •Shunt-related factors
- •Surface area
- •Plate material
- •Valved versus non-valved
- •Commercially available devices
- •Comparative studies
- •Patient and ocular factors
- •Severity of glaucoma damage
- •Tolerance of topical ocular hypotensive medications
- •Aqueous hyposecretion
- •Previous ocular surgery
- •Scleral thinning
- •Patient cooperation for and tolerance of potential slit-lamp interventions
- •Future challenges
- •Predictability
- •Cataract formation
- •The long-term effect on the cornea
- •References
- •Model systems for experimental studies: retinal ganglion cells in culture
- •Mixed RGCs in culture
- •Retinal explants
- •Glial cultures
- •RGC-5 cells
- •Differentiation of RGC-5 cells
- •RGC-5 cell neurites
- •Advantages and disadvantages of culture models
- •References
- •Rat models for glaucoma research
- •Rat models for glaucoma research
- •Use of animal models for POAG
- •Suitability of the rat for models of optic nerve damage in POAG
- •Methods for measuring IOP in rats
- •General considerations for measuring IOP in rats
- •Assessing optic nerve and retina damage
- •Experimental methods of producing elevated IOP
- •Laser treatment of limbal tissues
- •Episcleral vein cautery
- •Conclusions
- •Abbreviations
- •Acknowledgements
- •References
- •Mouse genetic models: an ideal system for understanding glaucomatous neurodegeneration and neuroprotection
- •Introduction
- •The mouse as a model system
- •Mice are suitable models for studying IOP elevation in glaucoma
- •Tools for glaucoma research
- •Accurate IOP measurements are fundamental to the study of glaucoma
- •The future of IOP assessment
- •Assessment of RGC function
- •Mouse models of glaucoma
- •Primary open-angle glaucoma
- •MYOC
- •OPTN
- •Strategies for developing new models of POAG
- •Developmental glaucoma
- •Pigmentary glaucoma
- •Experimentally induced models of glaucoma
- •Mouse models to characterize processes involved in glaucomatous neurodegeneration
- •Similar patterns of glaucomatous damage occur in humans and mice
- •The lamina cribrosa is an important site of early glaucomatous damage
- •An insult occurs to the axons of RGCs within the lamina in glaucoma
- •What is the nature of the insult at the lamina?
- •Other changes occur in the retina in glaucoma
- •PERG and complement
- •Using mouse models to develop neuroprotective strategies
- •Somal protection
- •Axonal protection
- •Erythropoietin administration
- •Radiation-based treatment
- •References
- •Clinical trials in neuroprotection
- •Introduction
- •Methods of clinical studies
- •Issues in the design and conduct of clinical trials
- •Clinical trials of neuroprotection
- •Clinical trials of neuroprotection in ophthalmology
- •Endpoints
- •Neuroprotection and glaucoma
- •Conclusions
- •Abbreviations
- •References
- •Pathogenesis of ganglion ‘‘cell death’’ in glaucoma and neuroprotection: focus on ganglion cell axonal mitochondria
- •Introduction
- •Retinal ganglion cells and mitochondria
- •Possible causes for ganglion cell death in glaucoma
- •Mitochondrial functions and apoptosis
- •Mitochondrial function enhancement and the attenuation of ganglion cell death
- •Creatine
- •Nicotinamide
- •Epigallocatechin gallate
- •Conclusion
- •References
- •Astrocytes in glaucomatous optic neuropathy
- •Introduction
- •Quiescent astrocytes
- •Reactive astrocytes in glaucoma
- •Signal transduction in glaucomatous astrocytes
- •Protein tyrosine kinases (PTKs)
- •Serine/threonine protein mitogen-activated kinases (MAPKs)
- •G protein-coupled receptors
- •Ras superfamily of small G proteins
- •Astrocyte migration in the glaucomatous optic nerve head
- •Cell adhesion of ONH astrocytes
- •Connective tissue changes in the glaucomatous optic nerve head
- •Extracellular matrix synthesis by ONH astrocytes
- •Extracellular matrix degradation by reactive astrocytes
- •Oxidative stress in ONH astrocytes
- •Conclusions
- •Acknowledgments
- •References
- •Glaucoma as a neuropathy amenable to neuroprotection and immune manipulation
- •Glaucoma as a neurodegenerative disease
- •Oxidative stress and free radicals
- •Excessive glutamate, increased calcium levels, and excitotoxicity
- •Deprivation of neurotrophins and growth factors
- •Abnormal accumulation of proteins
- •Pharmacological neuroprotection for glaucoma
- •Protection of the retinal ganglion cells involves the immune system
- •Searching for an antigen for potential glaucoma therapy
- •Concluding remarks
- •References
- •Oxidative stress and glaucoma: injury in the anterior segment of the eye
- •Introduction
- •Oxidative stress
- •Trabecular meshwork
- •IOP increase and free radicals
- •Glaucomatous cascade
- •Nitric oxide and endothelins
- •Extracellular matrix
- •Metalloproteinases
- •Other factors of interest
- •Therapeutic and preventive substances of interest in glaucoma
- •Ginkgo biloba extract
- •Green tea
- •Ginseng
- •Memantine and its derivates
- •Conclusions
- •Abbreviations
- •References
- •Conclusions on neuroprotective treatment targets in glaucoma
- •Acknowledgments
- •References
- •Involvement of the Bcl2 gene family in the signaling and control of retinal ganglion cell death
- •Introduction
- •Intrinsic apoptosis vs. extrinsic apoptosis
- •The Bcl2 family of proteins
- •The requirement of BAX for RGC soma death
- •BH3-only proteins and the early signaling of ganglion cell apoptosis
- •Conclusion
- •Abbreviations
- •Acknowledgments
- •References
- •Assessment of neuroprotection in the retina with DARC
- •Introduction
- •DARC
- •Introducing the DARC technique
- •Annexin 5-labeled apoptosis and ophthalmoloscopy
- •Detection of RGC apoptosis in glaucoma-related animal models with DARC
- •Assessment of glutamate modulation with DARC
- •Glutamate at synaptic endings
- •Glutamate excitotoxicity in glaucoma
- •Assessment of coenzyme Q10 in glaucoma-related models with DARC
- •Summary
- •Abbreviations
- •Acknowledgment
- •References
- •Potential roles of (endo)cannabinoids in the treatment of glaucoma: from intraocular pressure control to neuroprotection
- •Introduction
- •The endocannabinoid system in the eye
- •The IOP-lowering effects of endocannabinoids
- •Endocannabinoids and neuroprotection
- •Conclusions
- •References
- •Glaucoma of the brain: a disease model for the study of transsynaptic neural degeneration
- •Retinal ganglion cells, retino-geniculate neurons
- •Lateral geniculate nucleus
- •Mechanisms of RGC injury in glaucoma
- •Transsynaptic degeneration of the lateral geniculate nucleus in glaucoma
- •Neural degeneration in magno-, parvo-, and koniocellular LGN layers
- •Visual cortex in glaucoma
- •Neuropathology of glaucoma in the visual pathways in the human brain
- •Mechanisms of glaucoma damage in the central visual pathways
- •Implications of central visual system injury in glaucoma
- •Conclusion
- •Acknowledgments
- •References
- •Clinical relevance of optic neuropathy
- •Is there a remodeling of retinal circuitry?
- •Behavioral consequences of glaucoma
- •Glaucoma as a neurodegenerative disease versus neuroplasticity and adaptive changes
- •Future directions
- •Acknowledgment
- •References
- •Targeting excitotoxic/free radical signaling pathways for therapeutic intervention in glaucoma
- •Introduction
- •Channel properties of NMDA receptors correlated with excitotoxicity
- •Downstream signaling cascades after overactivation of NMDA receptors
- •Relevance of excitotoxicity to glaucoma
- •Therapeutic approaches to prevent RGC death by targeting the pathways involved in NMDA excitotoxicity
- •Drugs targeting NMDA receptors
- •Kinetics of NMDA receptor antagonists
- •Memantine
- •NitroMemantines
- •Drugs targeting downstream signaling molecules in NMDA-induced cell death pathways
- •p38 MAPK inhibitors
- •Averting caspase-mediated neurodegeneration
- •Abbreviations
- •Acknowledgments
- •References
- •Stem cells for neuroprotection in glaucoma
- •Introduction
- •Glaucoma as a model of neurodegenerative disease
- •Why use stem cells for neuroprotective therapy?
- •Stem cell sources
- •Neuroprotection by transplanted stem cells
- •Endogenous stem cells
- •Key challenges
- •Conclusion
- •Abbreviations
- •Acknowledgments
- •References
- •The relationship between neurotrophic factors and CaMKII in the death and survival of retinal ganglion cells
- •Introduction
- •Glaucoma and the RGCs
- •Are other retinal cells affected in glaucoma?
- •Retinal ischemia related glaucoma
- •Excitotoxicity and the retina
- •Signal transduction
- •NMDA receptor antagonists and CaMKII
- •Caspase-3 activation in NMDA-induced retinal cell death and its inhibition by m-AIP
- •BDNF and neuroprotection of RGCs
- •Summary and conclusions
- •Abbreviations
- •Acknowledgments
- •References
- •Evidence of the neuroprotective role of citicoline in glaucoma patients
- •Introduction
- •Patients: selection and recruitment criteria
- •Pharmacological treatment protocol
- •Methodology of visual function evaluation: electrophysiological examinations
- •PERG recordings
- •VEP recordings
- •Statistic evaluation of electrophysiological results
- •Electrophysiological (PERG and VEP) responses in OAG patients after the second period of evaluation
- •Effects of citicoline on retinal function in glaucoma patients: neurophysiological implications
- •Effects of citicoline on neural conduction along the visual pathways in glaucoma patients: neurophysiological implications
- •Possibility of neuroprotective role of citicoline in glaucoma patients
- •Conclusive remarks
- •Abbreviations
- •References
- •Neuroprotection: VEGF, IL-6, and clusterin: the dark side of the moon
- •Neuroprotection: VEGF-A, a shared growth factor
- •VEGF-A isoforms
- •VEGF-A receptors
- •Angiogenesis, mitogenesis, and endothelial survival
- •Neurotrophic and neuroprotective effect
- •Intravitreal VEGF inhibition therapy and neuroretina toxicity
- •Neuroprotection: clusterin, a multifunctional protein
- •Clusterin/ApoJ: a debated physiological role
- •Clusterin and diseases
- •Clusterin and the nervous system
- •Neuroprotection: IL-6, VEGF, clusterin, and glaucoma
- •Rational basis for the development of coenzyme Q10 as a neurotherapeutic agent for retinal protection
- •Introduction
- •Ischemia model
- •Neuroprotective effect of Coenzyme Q10 against cell loss yielded by transient ischemia in the RGC layer
- •Retinal ischemia and glutamate
- •Coenzyme Q10 minimizes glutamate increase induced by ischemia/reperfusion
- •Summary
- •Acknowledgment
- •References
- •17beta-Estradiol prevents retinal ganglion cell loss induced by acute rise of intraocular pressure in rat
- •Methods
- •Morphometric analysis
- •Microdialysis
- •Drug application
- •Statistical analysis
- •Results
- •17beta-Estradiol pretreatment minimizes RGC loss
- •Discussion
- •Acknowledgment
268
Fig. 4. With non-valved shunts, such as the Baerveldt or Molteno implants, an occlusive ligature is required to prevent hypotony in the early postoperative period. In (A) and (B) (arrow) a 7/0 vicryl (Ethicon, Johnson & Johnson International, Brussels, Belgium) is used to produce total occlusion. Adapted with permission from Shaarawy et al. (2008). Courtesy of Moorfields Eye Hospital.
area (184 mm2). The tube portions are identical and approximately 23 gauge in external diameter. Versions with smaller plates designed for pediatric eyes are also available.
2.The Baerveldt Glaucoma Implant features a large (250 or 350 mm2) flexible silicone plate that is noticeably different from the Ahmed valve in that it is significantly thinner and
broader, and is barium impregnated to make it radio-opaque. The wings of the 350-mm2 implant (101-350 or 102-350) are usually placed under the adjacent rectus muscles. In order to avoid interference with muscle function, they are often placed about 1 mm behind the muscle insertion and the plate is secured tightly to sclera to avoid movement.
It is also possible to implant the Baerveldt 101-350 with the wings on top of the muscles, and this is sometimes performed in patients with extensive scarring around the muscles,
most commonly in patients who have had extensive retinal surgery. The 250-mm2 implant has smaller wings, which extend less far under the adjacent rectus muscles.
3.The classical Molteno implant is available as a single polypropylene plate (135 mm2) and as a double-plated version in which the two plates are connected by a tube, similar in
manufacture to the anterior chamber tube portion of the implant. The implant is designed so that the two plates sit in the superonasal and superotemporal quadrants (or inferonasal and inferotemporal), respectively, and the interconnecting tube courses under the superior (or inferior) rectus muscle. This necessitates passing one of the plates under the relevant rectus muscle during implantation, although some surgeons drape the interconnecting tube over the interposed rectus muscle rather than passing a plate under it.
A modification of the Molteno implant includes a pressure ridge that was designed to retard filling of the bleb and prevent hypotony. A smaller pediatric version of the Molteno implant also exists.
The Molteno 3 implant is a flexible larger singleplate implant that has recently been released. There are two plate sizes, 175 and 230 mm2.
Comparative studies
At the time of writing, nonrandomized retrospective studies provide the majority of comparative data between the Baerveldt implant and the Ahmed Glaucoma Valve (Tsai et al., 2006), though
