GLAUCOMA & CATARACT GLAUCOMA from the Greek glaucos which means „watery blue“ GLAUCOMA lone of the most common causes of irreversible blidness lan uncurable disease GLAUCOMA in the Czech Republic lpopulation 10 mil. lglaucoma patients approximately 200 000 – 300 000 l600 glaucoma sugreries a year lapproximately every 20. patient in the ambulatory servise has glaucoma l TYPE OF GLAUCOMA •open angle glaucoma •intraocular hypentension •angle closure glaucoma •normal tension glaucoma lIn recent history glaucoma had been defined by having an intraoccular pressure (IOP) above 21mmHg lLater research indicated that the majority of people with IOPs above 21mmHg do not develop typical glaucomatous changes lOur modern concept of primary open angle glaucoma is a description of the constellation of sings frequently seen in „glaucoma“ that incorporate IOP, optic nerve appearance, and characteristic visual field changes •A more modern definition for glaucoma is as follows: a pathologic condition in which there is a progressive loss of ganglion cell axons causing visual field damage that is related to IOP l •Currently, we look to evaluate the following components when making the diagnosis of glaucoma: history, presence or absence risk factors, IOP, optic nerve examination and visual field testing l glauko45 THE OPTIC DISC The optic nerve conteins over 1 milion axons of the retinal ganglion cells, the cell bodies of which are in the superficial retinal layers Futurum5 The shape of the optic disc is usually a vertical oval, in the center of the disc is a depressed region, the cup, which is typically a horizontal oval THE OPTIC DISC The central region is usually pale owing to the absence of axons with exposure of the underlying lamina cribrosa. The tissue between the cup and the disc margins is referred to as the neuroretinal rim and represents the location of the bulk of the axons of the ganglion cells. This tissue has usually an orange-red hue because of the associated capillaries THE OPTIC DISC Determination of optic disc size is extremely important in evaluating glaucomatous optic neuropathy. The optic disc size is correlated with the optic cup and neuroretinal rim: the larger the optic disc, the larger cup disc and neuroretinal rim. VARIATIONS IN OPTIC DISC SIZE glaukom5 A B A - a small optic disc with no cup by high hypermetropic eye B – a large optic disc with a physiologically large cup by high myopic eye GLAUCOMATOUS OPTIC DISC Degeneration of retinal ganglion cell axons in glaucoma leads to an increase in cup size with loss of neuroretinal rim tissue. Focal loss of the neuroretinal rim often begins as a small, localised defect in the contour of the inner edge of the cup, leading to narrowing of the rim. PODLOUCKÁ OS ZDENK1 KOTÍK OS JIŘ1 GLAUCOMATOUS OPTIC DISC This defect may enlarge and develop a sharp margin. Vessels crossing this sharpened rim bend abruptly, this is referred to as bayoneting and is a useful marker of rim loss. PODLOUCKÁ OS ZDENK1 There is also an associated nerve fiber layer defect present as wedge-shaped area of attenuation of the nerve fiber layer KOTÍK OS JIŘ1 H&E stained histologic section of optic nerves. A –normal optic nerve; B- optic nerve from advanced glaucoma A B lIntraocular pressure remains one of the most important risk factors for the disease l lAdditionally, lowering of the intraocular pressure is the only rigorously proven treatment for glaucoma l lAlthough we have some understanding of the physiology of the IOP, we do not yet fully understand how the eye regulates intraocular pressure at the cellular and molecular level glauko50 glauko51 glauko53 Aqueous is formed in the ciliary processes (pars plicata region of the retina). The epithelial cells of the inner nonpigmented layer are felt to be the site of aqueous production. Aqueous is produced by a combination of active secretion, ultrafiltration and diffusion. glauko54 glauko55 Aqueous the flows through the pupil and ino the anterior chamber nourshing the lens, cornea and iris Aqueous drains through the anterior chamber angle, which conteins trabecular meshworkand ciliary body ROUT OF AQUEOUS FLOW glauko37 A)between 80-90% of agueous outflow is through the trabecular meshwork: the co-called conventional pathway B)With the remaining 10-20% through the ciliary body face: the co-called uveoscleral or alternative pathway A B lIntraocular pressure is physiologically determined by rate of aqueous production in the ciliary body, resistance to outflow through the conventional outflow tract (trabecular meshwork and Schlemm´s canal), resistence to outflow through the unconventional outflow (uveoscleral), and episcleral venous pressure l lElevation of episcleral venous pressure or changes in the trabecular meshwork can result in an elevated intraocular pressure GLAUCOMA RISK FACTORS §Intraocular pressure §Age (mostly by older patients) §Family history (genetic) §Rasa (black persons have higher IOP) §Sex (female more often) §Refractive errores §Diabetes, hypertension CLINICAL EXAMINATION §History §Visual acuity §Biomikroscopy slit lamp observation §Tonometry IOP measurement §Gonioscopy observation of the anterior chamber angle §Perimetry visual field testing §Pachymetry measurement of thickness of the cornea §Optic disc observation (direct, indirect,documentation) §Measurement of the tickness of the nerve fiber layer BIOMIKROSCOPY glaukom7 glaukom8 TONOMETRY measurement of the IOP §palpation § l §applanation § § § § §noncontact l l l l glaukom9 glauko30 glauko33 The patient is seated at the slit lamp, the cornea is viewed throught a prismatic doubling device, the applanation head is gently placed against a fluorescein-stained, anesthetized cornea. The examiner sees a split image of the tear meniscus around the tonometr head. These fluorescein rings just overlap when the pressure at the head eguals the intraocular pressure. Goldmann applanation, the „gold standard“ of measurement of IOP: an area of the cornea is deforming with small amount of force that is used to calculate the IOP glauko31 glauko32 glauko30 glauko29 glauko34 Gonioscopy visualisation of the configuration of the anterior chamber angle: The angle is visualized with the lens that has one or more mirrors, allowing the evaluation of the structures opposite to the mirror employed. The examinantion is permormed using the slit lamp. To obtain a good view of the angle, the incidence of the light beam must be perpendicular to the mirror of the lens. glauko35 Gonioscopy stra9 Perimetry: visual field testing §Psychophysical testing – the subjective testing of peripheral vision of the eye (glaucoma affects the peripheral vision before affecting central acuity) § §Glaucomatous visual field defects are those that are typically found with lesions localizing to the optic nerve (visual field abnormalities have localizing value for lesions along the entire visual tract: from retrina to occipital lobes) § §Perimetric testing attemps to determine the visual threshold at a particular location in the visual field. The visual treshold is defined as the minimum level of light that can be perceived at a given location in the visual field. This concept is also termed retinal sensitivity. Perimetry •The visual threshold is highest in the fovea, which is defined as the center of the visual field. As the field extends peripherally, the sensitivity decreases. •There are two main methods of perimetry: static and kinetic •Static visual field testing presents visual stimuli in varying sizes and intensities at fixed locations. This testing is automated and presents white-colored stimuli on a standard background glauko46 B A B C A – normal eye B – beginning of glaucoma C – advanced stage of glaucoma glauko49 glauko48a tesařOL1 tesařOL2 tesařOP1 tesařOP2 Patient, 55 years old, POAG billat. DOCUMENTATION OF THE OPTIC DISC PLOČEK OS FRANTIŠE1 LANGROVÁ OS IVET1 ŠACHOVÁ OD NATAŠ1 KOTÍK OS JIŘ1 BLAHUTKA OS VĚROSLA1 KALOUSKOVÁ OD JARMIL1 st5 Laser tomografy Strak6 Laser tomografy MEASUREMENT OF THE TICKNESS OF THE NERVE FIBER LAYER •The nerve fiber are the axons of the ganglion cells, their losses indicate the losses of the ganglion cells •The visual field defects corelate with the changes in the nerve fiber layer l l l new10 new10 Differences of the size and the form of the optic disc Uniformity in the nerve fiber layer 100% difference 97% uniformity Slit lamp observation of the nerve fiber layer sterbinka2 sterbinka1 foto sitnice PODLOUCKÁ OS ZDENK1 nerve fiber layer defect present as wedge-shaped area of atte-nuation of the nerve fiber layer glauko10 Laser scan of the nerve fiber layer Typies of glaucoma §primary §secundary § §acute §chronic §intermittent § §congenital §juvenil §adult Prrimary Congenital Glaucoma (PCG) §More than 80% of cases present before 1 year of age: 40% at birth, 70% between 1-6 months §75% of PCG cases occur bilaterally §The disorder is more common in males and 90% of cases are sporadic, without family history §Although an autosomal recessive model with variable penetrance has been suggested glauko13 glauko14 Prrimary Congenital Glaucoma (PCG) glauko11 glauko12 Normal anterior chmber angle The developmental abnormatily of the anterior chamber angle The treatment of PCG is always surgical. Medical treatment can be used for a limited time. Procedures that involve trabecular incisions are the choice in this condition glauko15 glauko16 Goniotomy requires a clear cornea for visialisation of the angle Trabeculotomy with an external approach to Schlemm´s canal does not require thr clear cornea Primary open angle glaucoma (POAG) §Leading cause of irreversible blindness (the incidence of glaucoma is estimate at around 2,5 million per year, blindness people is probably around 3 million) §The majority of patients are older than 60 years of age §The common pathway in the POAG is the death, sometimes by necrosis, but usually by apoptosis, of the retinal ganglion cell. This may lead to further demage, in the retina, optic nerve, and brain §The patient with POAG has no problems for a long time glaukom1 4 otevreny KU PRIMARY ANGLE CLOSURE GLAUCOMA (PACG) §arising from a preexisting iris configuration 2a 3 uzavreny KU, PAS glaukom2 glaukom6 § the apposition of the iris sphincter to the anterior lens capsule (pupillary blok)may cause an increase in pressure behind the iris and mechanical obstruction of outflow through TM PRIMARY ANGLE CLOSURE GLAUCOMA (PACG) •If the pupillary blok is large and the angle is already very narrow, then complete obstruction of the TM occurs, and the IOP rise dramaticaly resulting acute angle closure glaucoma • •By acute PACG symptoms range from unilate-ral mild blurring and pain to extreme pain, nausea, vomiting. These symptoms often occure during the evening. Attacts may be associated with dim illumination, stress, or prolonged near work PRIMARY ANGLE CLOSURE GLAUCOMA (PACG) •If the pupillary blok is small, the angle is narrow, and theTM is blocked only in small portion, then IOP rises very slowly, often over many years. This proces is termed chronic primary angle closure glaucoma • •By chronic PACG usually, there are no symptoms. Once the closure is complete, the pressure may rise acutely, and the patient may experience pain PRIMARY ANGLE CLOSURE GLAUCOMA (PACG) •Subacute angle-closure lies between acute and chronic with regard to the amount of time the IOP rises. • •Symptoms of subacute angle closure include intermittent attacks of pain and possibly mildly blurry vision. Symptoms often occur with dim illumination, stress, and near work. Sleep may break the attack. This may be confused with migraine headache. glaukom7 glaukom8 ACUTE ANGLE CLOSURE GLAUCOMA The affected eye may show intensive conjunctival hyperemia, mild-dilatated pupil, corneal edema, and shallow anterior chamber. The iris is often in a bombé pattern. The IOP may be as high as 80mmHg. Early in the attack, the optic nerve head show edema and hyperemia MANAGEMENT OF ACUTE PACG •The most common treatment method is to first lower the pressure by aqueous suppresants and osmotic agents. Miotics cause pupillary muscle constriction , which is believed to pull open the TM to increase trabecular outflow.Hyperosmolar agents dehydrates the vitreous and decreases intraocular fluid volume by osmotic drawing fluid into the intravascular space. • •This medicaments may allowing the lens-diaphragm to move posterioly and changing the fluid dynamics causing the pupilary blok. • •Once the corneal edema has cleared, a laser peripheral iridotomy can be performed. MANAGEMENT OF ACUTE PACG KOCOVA_KVETUSE__28_08_2006__10_09__001 KOCOVA_KVETUSE__03_08_2006__09_28__001 glauko40 glauko39 Laser iridotomy SECUDARY GLAUCOMA - open angle §lens – associated glaucoma: lens particle glaucoma, lens protein glaucoma and lens-associated uveitis §lens particle glaucoma: lens material obstruct TM, disruption to lens capsule with release of lens particule (extracapsular cataract surgery, trauma, Nd-YAG laser) – §lens protein glaucoma: – heavy-molecular-weight – lens proteins obstruct – TM, mature or hyper- – mature cataract výukaang1 Mature cataract with folds in the anterior capsule SECUDARY GLAUCOMA - open angle §lens-associated uveitis (phacoanaphylactis uveitis ): loss of immune tolerance to lens proteins, disruption to lens capsule, exposure of large lens fragments. Rare granu-lomatous inflammation that develops in situation in which the immune system is exposed to lens proteins (after complicated cataract extraction, traumatic rupture of the lens capsule, extraction of the mature or hypermature cataract) výukaan1 výukaan2 Intense AC inflammation Corneal swelling, Descemet´s folds SECUDARY GLAUCOMA – open angle §steroid responsive glaucoma – the incidence is related to the type, dose, and route of steroid administration (topical, intraocular, pariocular, inhaled, oral, intravenous, dermatological) increased glycosaminoglycans in the TM in response to steroids impede aqueous outflow and lead to elevated IOP §uveitic glaucoma - multifa- – ctorial process that can be – viewed as a complication of – the intraocular inflammation, – abnormal aqueous secretion, – proteins, prostaglandins, infla- – mmmatory cells, trabeculitis, – steroid-induced glauko20 SECUDARY GLAUCOMA – open angle §uveitic glaucoma – §more common by anterior uveitis and panuveitis §more often by granulomatous uveitis §the prevalence of glaucoma secondary to uveitis in adults varies from 5,2 to 19% §visual prognosis for children with uveitic glaucoma is worse § glauko19 TRAUMATIC GLAUCOMA lFollowing blunt or penetrating trauma to the globe, patients often develop difficulties with IOP control. IOP may be elevated acutely or many years following the injury. Trauma can result in injury to any of the ocular structures. výukaan3 výukaan4 Traumatic hyphema Angle recession – irregular widening of the ciliary body band SECONDARY angle-closure GLAUCOMA §neovascular glaucoma – most commonly occur after ischemic central retinal vein occlusion and proliferative diabetic retinopathy. A fibrovascular membrane grows over (tm) and closing the anterior chamber angle § § § § § § § luzna anna glauko23 Neovascularization of the iris is seen near the pupillary margin Central retina after ischemic retinal vein occlusion GLAUCOMA MANAGEMENT •the goal of glaucoma treatment is to retard or halt the ganglion cell loss to prevent symptomatic visual loss • •medications, laser , surgery – initial treatment • •there are several different classes of medications. All medications work to lower IOP through varying pharmacologic mechanisms • •IOP is determined by the balance between secretion and drainage of aqueous humor. All medications either decrease secretion or increase outflow PHARMACOLOGIC AGENTS •Alpha Agonists •Beta-BLOCKERS •Carbonic Anhydrase Inhiobitors – Oral •Carbonic Anhydrase Inhibitors – topical •Hyperosmolar Agents •Miotics •Prostaglandins •Sympatomimetic Agens •Combination Agents l glauko41 glauko42 Laser trabeculoplasty §Argon-laser trabeculoplasty ALT §Selective laser trabekuloplasty SLT ARGON LASER TRABECULOPLASTY lThe laser spot (size 50μm) is aimed at the junction of the pigmented and nonpigmented TM. A single treatment session of the entire 360 degrees with up 100 applications, or two sessions of 180 degrees each with 50 shots, may be performed. l lThe termal burn with Argon l laser cause melting and distor- l tion of the trabecular beams. l The contraction burns over the l angle mechanically helped adja- l cent trabecular beams open l wider , thus allowing easier l aqueous outflow výukaan5 SELECTIVE LASER TRABECULOPLASTY •In contrast with the continuous wave argon laser, the selective laser does not cause any thermal injury to the trabeculum. The fixed spot size of 400μm draws the typical 50-μm spot size used by ALT. The spot size with SLT is so large that the entire angle is covered with aiming beam. výukaan6 lA –Argon burn resulted in coagu-lative melting of the trabecular beam. Lower magnification showing the crater, the curling of the collagen caused by the thermal damage lB – The selective laser did not cause any significant structural alteration. A higher magnification showing the absence of a crater, a fracture one of the sheets of collagen výukaan7 A B GLAUCOMA SURGERY TRABECULECTOMY – – – – Trabeculectomy lowers the IOP by creating a fistula between the inner compartments and the subconjunctival space IPVZ7 IPVZ8 ANTIMETABOLITES •To reduce postoperative subconjunctival fibrosis, especially important in cases at high risk for failure, antifibrotic agents (antimetabo-lites Mitomycin C or 5-fluorouracil) are used. The use of this agents is associated with a higher success and complication rates for primary and high-risk trabeculectomies Š31 TRABECULEKTOMY – FILTERING BLEB Š26 š42 Bleb encapsulation TRABECULEKTOMY postoperative complications Š37 Š20 Š9 IPVZ14 Š5 Š4 Choroidal effusion TRABECULEKTOMY – FILTERING BLEB Gla 03 Gla 04 Confocal in vivo mikroskopy of the filtering bleb Stroma FP 1. day after surgery 1 month after surgery DEEP SCLERECTOMY l l l ltrabeculo – Descemet´s membrane IPVZ16 IPVZ17 glaukom8 DEEP SCLERECTOMY l l IPVZ18 IPVZ22 IPVZ23 DEEP SCLERECTOMY IPVZ11 IPVZ13 IPVZ19 IPVZ20 Laser goniopuncture collagen implant GLAUCOMA DRAINAGE DEVICES lGlaucoma drainage devices, also called aqueous shunts or tube shunts, are used to reduce the IOP in patinets with uncontrolled glaucoma in whom filtration surgery with antifibrotic agents has already failed or is unlikely to succeed GLAUCOMA DRAINAGE DEVICES š44 The shunting device consist of a posteriorly placed, episcleral plate implant connected to a silicon tube that is inserted into the eye, usually in the anterior chamber A posterior filtering bleb is formed around the episcleral implant. Aqueous is resorbed by venous cappilaries and lymphatics