II. Definitions
- Glaucoma
- Increased Intraocular Pressure AND Optic Nerve injury
- High risk of blindness if untreated (acuity <20/200)
III. Epidemiology
- Within top 3 worldwide causes of blindness
- Cataracts are the most common worldwide cause of blindness
- Leading cause of blindness in black patients in U.S.
- U.S. Prevalence: 3 Million
- Affects 3.5% of those over age 40 years (and increases with age)
- Only 50% are estimated to now be under treatment
- 120,000 are blind due to Glaucoma
- Highest risk groups for Glaucoma-related blindness in Blacks and Hispanics
- World Prevalence: 60 Million
- Bilateral blindness due to Glaucoma estimated at 11 million worldwide by 2020
IV. Physiology
-
Aqueous Humor
- Ciliary body produces Aqueous Humor
- Aqueous Humor flows through pupil and into anterior chamber
- Trabecular meshwork drains Aqueous Humor into the venous system
-
Intraocular Pressure
- Intraocular Pressure is a balance between Aqueous Humor production (ciliary body) and drainage (trabecular mesh)
- Intraocular Pressure may normally vary with Blood Pressure and respiration
- Introcular pressure typically decreases at night
-
Lamina Cribrosa of Sclera
- Sleeve-like space at the opening of the Sclera through which Retinal axons pass on their way to the Optic Nerve
- Represents hundreds of openings through which 1-2 Million nerves pass (bundled into groups)
- Retinal axons are particularly sensitive to injury at the lamina cribosa, where the axons bend and exit the eye
- Lamina Cribrosa is an important landmark for Glaucoma related-injury to Retinal axons
-
Neuroretinal Rim
- Outer, pink portion of the Optic Disc that surrounds the Optic Cup
- Neuroretinal Rim contains nerve fibers and glial cells
- Injury to the Retinal axons of the results in cell loss and thinning of the rim
- Glaucoma-related pressure induces Retinal axon injury and Neuroretinal Rim thinning
V. Pathophysiology
- Elevated Intraocular Pressure (IOP)
- Increased production of Aqueous Humor by ciliary body
- Aqueous Humor is typically produced at 2 ul/min
- Increased outflow resistance at Aqueous Outflow Angle
- Trabecular meshwork
- Canal of Schlemm
- Increased production of Aqueous Humor by ciliary body
- Progressive changes in Optic Disc
- Nerve damage related to increased IOP is variable
- Glaucoma suspects (66% of those with high IOP)
- No damage despite high Intraocular Pressure (>21)
- Optic Nerve injury rate in suspects: 1% per year
- Normal-pressure Glaucoma (15% of Glaucoma patients)
- Normal Intraocular Pressure (21 mmHg or less)
- Glaucoma-related Optic Nerve damage
- Glaucoma suspects (66% of those with high IOP)
- Progressive Glaucomatous cupping at the Optic Disc
- IOP collapses Optic Nerve Head structural support
- Retinal axons are destroyed by mechanical compression
- Nerve damage related to increased IOP is variable
- Peripheral Visual Field loss
- Open Angle Glaucoma: Slowly progressive
- Narrow Angle Glaucoma: Rapid Vision Loss
VI. Types
- Primary Glaucoma
- Open Angle Glaucoma (75 to 89% of cases in U.S.)
- Outflow blocked by microscopic outflow changes
- Results in progressive peripheral Vision Loss
- Usually asymptomatic until 40% of nerve loss
- Narrow Angle Glaucoma (11% of cases)
- Outflow tract blocked by base of iris
- Permanent Vision Loss may occur in hours
- Presents as acute painful Red Eye with Vomiting
- Open Angle Glaucoma (75 to 89% of cases in U.S.)
- Secondary Glaucoma
- Medications that increase IOP in those predisposed
- Corticosteroids (Systemic and Topical)
- Reversible
- Mild Adrenergic or Anticholinergic Medications
- Examples
- Cold Medications
- Antidepressants
- Antidiarrheals
- Effect: Dilate Pupil
- Theoretically worsen angle closure Glaucoma
- Not contraindicated in Glaucoma
- Examples
- Corticosteroids (Systemic and Topical)
- Medications that increase IOP in those predisposed
VII. Exam: Basic
-
Tonometry
- Intraocular Pressure >21 mmHg is consistent with Ocular Hypertension
-
Visual Field Testing
- Visual Fields by Confrontation
-
Optic Disc exam by Fundoscopy
- Enlarged cup-to-disc ratio >0.3 to 0.5 (or >0.2 difference between eyes) is consistent with Glaucoma
VIII. Exam: Ophthalmology
- Perimetry
- Automated testing of Visual Fields
-
Gonioscopy (Van Herrick Test)
- Evaluates Anterior Chamber Depth and angle
- Pachymetry
- Corneal thickness measurement
- Optical Coherance Tomography (OCT)
- Evaluates Optic Nerve Head anatomy by analyzing reflected light off the Optic Disc
- Neuroretinal Rim thinning identified on serial OCT evaluations often precedes Visual Field Deficits
IX. Differential Diagnosis
X. Resources
- Aging Eye Glaucomatrac (Glaucoma Management Tracking)
- Aging Eye Glaucoma Video
Images: Related links to external sites (from Bing)
Related Studies
| Definition (MEDLINEPLUS) |
Glaucoma is a group of diseases that can damage the eye's optic nerve. It is a leading cause of blindness in the United States. It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first. Without treatment, people with glaucoma will slowly lose their peripheral, or side vision. They seem to be looking through a tunnel. Over time, straight-ahead vision may decrease until no vision remains. A comprehensive eye exam can tell if you have glaucoma. People at risk should get eye exams at least every two years. They include
There is no cure, but glaucoma can usually be controlled. Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eyedrops and/or surgery. NIH: National Eye Institute |
| Definition (MSHCZE) | Zelený zákal. Onemocnění charakterizované zvýšeným nitroočním tlakem a následnými změnami vnitřních částí oka a poškozením zrakového nervu, které vede k poruchám vidění. G. postihuje až 2% populace středního a vyššího věku a v rozvinutých zemích patří k nejč. příčinám slepoty. Objeví-li se na oku zdravém, jde o primární g., jeho příčina není zcela jasná, je-li důsledkem jiného očního onemocnění (oční záněty, úraz aj.), jde o g. sekundární. Podstatou většiny druhů g. je zvýšení tlaku komorové vody v oku (zvýšená tvorba či poruchy jejího odtoku). Tento tlak lze při odborném očním vyšetření změřit. Akutní g. (vzácnější) se projevuje akutními záchvaty silné bolesti oka a hlavy, světloplachostí, zarudnutím oka, viděním barevných kruhů kolem zdrojů světla a různě velkou poruchou vidění (např. mlhavé vidění), někdy i nevolností a zvracením. Zrak se vlivem záchvatů zhoršuje, k čemuž může docházet postupně – a zákeřně – i bez akutních záchvatů (u chronického g. častější). Podstatou léčby je snižování nitroočního tlaku. Používají se oční kapky pilokarpin, betablokátory, popř. některé vnitřně podané léky snižující tvorbu komorové vody. V některých případech se používá laser nebo se provádí operace. Včasně zahájená a pečlivě prováděná léčba umožní nemoc zastavit a zabránit tak těžkému porušení zraku či dokonce slepotě. Vzniklá poškození však již nelze odstranit, proto je důležitá včasná diagnóza a pečlivé dodržování léčby. Některé vnitřně podané léky (atropin, spasmolytika) mohou u nemocného glaukomem vyvolat záchvat; řec. glaukos modrozelený. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ ) |
| Definition (NCI_CTCAE) | A disorder characterized by an increase in pressure in the eyeball due to obstruction of the aqueous humor outflow. |
| Definition (NCI_NCI-GLOSS) | A condition in which there is a build-up of fluid in the eye, which presses on the retina and the optic nerve. The retina is the layer of nerve tissue inside the eye that senses light and sends images along the optic nerve to the brain. Glaucoma can damage the optic nerve and cause loss of vision or blindness. |
| Definition (NCI) | Increased pressure in the eyeball due to obstruction of the outflow of aqueous humor. |
| Definition (MSH) | An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed) |
| Definition (CSP) | group of diseases characterized by increased intraocular pressure resulting in damage to the optic nerve and retinal nerve fibers. |
| Concepts | Disease or Syndrome (T047) |
| MSH | D005901 |
| ICD9 | 365.9, 365 |
| ICD10 | H40 , H40-H42.9, H40.9, H40-H42 |
| SnomedCT | 155120009, 194631001, 193569008, 23986001 |
| LNC | MTHU020819, LA16302-4 |
| English | Glaucomas, Glaucoma, Unspecified glaucoma, Glaucoma NOS, Glaucoma, unspecified, glaucoma (diagnosis), glaucoma, Glaucoma [Disease/Finding], glaucomas, Glaucoma (H40-H42), Glaucoma NOS (disorder), GLAUCOMA, Glaucoma (disorder), Glaucoma, NOS |
| French | GLAUCOME, Glaucome SAI, Glaucome, non précisé, Glaucome non précisé, Glaucome |
| Portuguese | GLAUCOMA, Glaucoma NE, Glaucoma |
| Spanish | GLAUCOMA, Glaucoma no especificado, Glaucoma NEOM, glaucoma, SAI (trastorno), glaucoma, SAI, glaucoma (trastorno), glaucoma, Glaucoma |
| German | GLAUKOM, Glaukom, unspezifisch, Glaukom NNB, unspezifisches Glaukom, Glaukom, nicht naeher bezeichnet, Glaukom, Star, grüner |
| Dutch | glaucoom NAO, glaucoom, niet-gespecificeerd, niet-gespecificeerd glaucoom, Glaucoom, niet gespecificeerd, glaucoom, Glaucoom |
| Italian | Glaucoma NAS, Glaucoma non specificato, Glaucoma |
| Japanese | 緑内障ＮＯＳ, 緑内障, 詳細不明の緑内障, 緑内障、詳細不明, ｼｮｳｻｲﾌﾒｲﾉﾘｮｸﾅｲｼｮｳ, ﾘｮｸﾅｲｼｮｳNOS, ﾘｮｸﾅｲｼｮｳｼｮｳｻｲﾌﾒｲ, ﾘｮｸﾅｲｼｮｳ |
| Swedish | Grön starr |
| Czech | zelený zákal oční, glaukom, Glaukom, Blíže neurčený glaukom, Glaukom NOS, zelený zákal |
| Finnish | Glaukooma |
| Russian | GLAUKOMA, ГЛАУКОМА |
| Korean | 상세불명의 녹내장, 녹내장 |
| Croatian | GLAUKOM |
| Polish | Jaskra |
| Hungarian | Glaucoma k.m.n., Glaucoma, nem meghatározott, Glaucoma, Nem meghatározott glaucoma |
| Norwegian | Glaukom, Grønn stær |
Ontology: Ocular Hypertension (C0028840)
| Definition (MSHCZE) | Stav se zvýšeným nitroočním tlakem. Viz glaukom. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ ) |
| Definition (MSH) | A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma. |
| Concepts | Disease or Syndrome (T047) |
| MSH | D009798 |
| ICD9 | 365.04 |
| ICD10 | H40.05 |
| SnomedCT | 267721003, 193536008, 155121008, 4210003 |
| English | Hypertension, Ocular, Hypertensions, Ocular, Ocular Hypertension, Ocular Hypertensions, HYPERTENSION OCULAR, preglaucoma ocular hypertension (diagnosis), preglaucoma ocular hypertension, Hypertension ocular, Ocular Hypertension [Disease/Finding], hypertension ocular, ocular hypertension, Ocular hypertension, OH - Ocular hypertension, OHT - Ocular hypertension, Ocular hypertension (disorder), hypertension; ocular, ocular; hypertension |
| French | HYPERTENSION OCULAIRE, Hypertension oculaire, Hypertonie oculaire, Hypertension intra-oculaire, Hypertension intraoculaire |
| Portuguese | HIPERTENSAO OCULAR, Hipertensão ocular, Hipertensão Ocular |
| Spanish | HIPERTENSION OCULAR, hipertensión ocular (trastorno), hipertensión ocular, Hipertensión ocular, Hipertensión Ocular |
| Italian | Ipertensione dell'occhio, Ipertensione oculare |
| Dutch | hypertensie oculair, hypertensie; oculair, oculair; hypertensie, oculaire hypertensie, Hypertensie, oculaire, Oculaire hypertensie |
| German | Erhoehung des Augeninnendrucks, AUGENINNENDRUCK ERHOEHT, Augeninnendruck erhoeht, Augeninnendruck, erhöhter, Hypertension, okuläre, Okuläre Hypertension |
| Swedish | Högt ögontryck |
| Japanese | ｺｳｶﾞﾝｱﾂｼｮｳ, 疑緑内障, 高眼圧症, 眼圧亢進, 高眼圧 |
| Finnish | Suurentunut silmänpaine |
| Russian | GLAZNAIA GIPERTENZIIA, GLAUKOMA SIMPTOMATICHESKAIA, GIPERTENZIIA GLAZA SIMPTOMATICHESKAIA, ГИПЕРТЕНЗИЯ ГЛАЗА СИМПТОМАТИЧЕСКАЯ, ГЛАЗНАЯ ГИПЕРТЕНЗИЯ, ГЛАУКОМА СИМПТОМАТИЧЕСКАЯ |
| Czech | Oční hypertenze, oční hypertenze, oči - hypertenze, hypertenze okulární |
| Croatian | Not Translated[Ocular Hypertension] |
| Polish | Nadciśnienie wewnątrzgałkowe, Nadciśnienie oczne |
| Hungarian | Ocularis hypertensio, Hypertonia ocularis |
| Norwegian | Okulær hypertensjon |
Ontology: Raised intraocular pressure (C0234708)
| Concepts | Finding (T033) |
| SnomedCT | 112222000, 155121008, 267721003, 193536008 |
| English | INTRAOCULAR PRESSURE INCREASED, Increased intraocular pressure, OCULAR TENSION INCREASED, high intraocular pressure, intraocular pressure was increased, Intraocular pressure high, Intraocular pressure increased, Pressure intraocular increased, Ocular tension increased, Tension ocular increased, Intraocular pressure raised, Raised IOP, increased intraocular pressure (physical finding), increased intraocular pressure, increase intraocular pressure, raised intraocular pressure, intraocular pressure increase, Raised intra-ocular pressure, Increased intra-ocular press., IOP increased, Elevated intraocular pressure, Raised intraocular pressure, Raised intraocular pressure (finding), intraocular; increased pressure |
| Italian | Pressione intraoculare aumentata, Pressione endooculare aumentata, Pressione intraoculare elevata, Tensione oculare aumentata, Pressione oculare aumentata |
| Dutch | spanning oculair verhoogd, intraoculaire druk gestegen, verhoogde intraoculaire druk, intraoculaire druk hoog, IOD verhoogd, gestegen IOP, druk intraoculair verhoogd, oogdruk verhoogd, intraoculair; drukverhoging, intraoculaire druk verhoogd |
| French | Tension oculaire augmentée, Elévation de la pression intraoculaire, Elévation de la PIO, Pression intraoculaire augmentée, PIO (pression intra-oculaire) augmentée, Pression intraoculaire élevée, AUGM PRESSION INTRAOCULAIRE, ELEVATION DE LA TENSION OCULAIRE, Pression intra-oculaire augmentée |
| German | intraokulaerer Druck hoch, Druck intrakraniell erhoeht, intraokulaerer Druck gestiegen, Augenspannung erhoeht, erhoehter intraokulaerer Druck, Spannung Auge erhoeht, gestiegener intraokulaerer Druck, AUGENDRUCKERHOEHUNG, DRUCKSTEIGERUNG INTRAOKULAER, intraokulaerer Druck erhoeht |
| Portuguese | Tensão intra-ocular elevada, Tensão intra-ocular aumentada, Pressão intra-ocular aumentada, Tensão intra-ocular alta, Pressão intraocular aumentada, PIO elevada, PRESSAO INTRAOCULAR AUMENTADA, TENSAO OCULAR AUMENTADA, Tensão intraocular aumentada |
| Spanish | Presión intraocular alta, PIO aumentada, Tensión ocular aumentada, Presión intraocular elevada, Presión ocular aumentada, PIO elevada, PRESION INTRAOCULAR AUMENTADA, TENSION INTRAOCULAR AUMENTADA, aumento de la presión intraocular, presión intraocular aumentada (hallazgo), presión intraocular aumentada, presión intraocular elevada, Presión intraocular aumentada |
| Japanese | ＩＯＰ上昇, 眼圧上昇, 眼圧高値, IOPｼﾞｮｳｼｮｳ, ｶﾞﾝｱﾂｼﾞｮｳｼｮｳ, ｶﾞﾝｱﾂｺｳﾁ |
| Czech | Nitrooční tlak zvýšený, Nitrooční tlak vysoký, Zvýšený NOT, Oční tlak zvýšený, NOT zvýšený, Zvýšený nitrooční tlak |
| Hungarian | Szembelnyomás magas, Emelkedett intraokuláris nyomás, Szembelnyomás emelkedett, Intraocularis nyomás megemelkedett, Szembelnyomás megemelkedett, Intraocularis nyomás emelkedett, IOP emelkedett |
