Glaucoma

Opthalmology

1. GLAUCOMA NUR IZZATUL NAJWA 08201510036

2. DEFINITION OF GLAUCOMA A group of disorders characterized by a progressive optic neuropathy , characteristic appearance of the optic disc , specific pattern of irreversible visual field defects , associated frequently but not invariably with raised IOP.

3. HOW GLAUCOMA CAN OCCUR? The pathophysiology of glaucoma revolves around the aqueous humour dynamics which are : Ciliary body (site of aqueous production ) Angle of anterior chamber ( aqueous drainage ) Aqueous outflow system Trabecular meshwork Schlemm’s canal Collector channels

4. ANGLE OF ANTERIOR CHAMBER Formed by : root iris, anterior-most part of ciliary body, scleral spur, trabecular meshwork and Schwalbe’s line (prominent end of Descemet’s membrane of cornea ).

5. Shaffer’s system of grading the angle width Grade Angle width Configuration Risk of closure Structures visible on gonioscopy 4 40 Wide angle Closure impossible SL, TM, SS, CBB 3 30 Open angle Closure impossible SL, TM, SS 2 20 Moderately narrow Closure possible SL, TM 1 10 Very narrow High risk of closure SL only S <10 Slit angle Closure imminent None Closed Closed None

6. (A ) = Gonioscopic view SL = Schwalbe’s line TM = Trabecular meshwork SS = Scleral spur (B) = Cross-section of anterior chamber CBB = Ciliary body band ROI = root of iris

7. AQUEOUS OUTFLOW SYSTEM Trabecular meshwork Uveal meshwork Corneoscleral meshwork Juxtacanalicular (endothelial) meshwork Schlemm’s canal Collector channels a.k.a intrascleral aqueous vessels Direct system = aqueous veins to episcleral veins Indirect system = smaller collector channels form intrascleral plexus to episcleral veins

8. PHYSIOLOGY OF AQUEOUS HUMOR Volume Anterior chamber (0.25ml) Posterior chamber (0.06ml ) Refractive index 1.336 . Functions Maintenance of a proper intraocular pressure. Metabolic and nutritional role. Optical function (maintain optical transparency). C learing function (blood, macrophages, remnants of lens matter). Composition Water (99.9%), proteins (colloid content), amino acid, oxygen in dissolved state, noncolloid constituents Similar to plasma except that it has: High concentrations of bicarbonate, ascorbate , pyruvate and lactate. Low concentration of protein, urea and glucose.

9. AQUEOUS OUTFLOW SYSTEM AQUEOUS HUMOUR PRODUCTION : ULTRAFILTRATION SECRETION (ACTIVE TRANSPORT ) DIFFUSION (PASSIVE TRANSPORT)

10. AQUEOUS OUTFLOW SYSTEM TRABECULAR MESHWORK (CONVENTIONAL) Normal production rate : 2.3 µl/min.

11. AQUEOUS OUTFLOW SYSTEM UVEOSC L ERAL OUTLOW (UNCONVEN- TIONAL)

12. Intraocular pressure (IOP) refers to the pressure exerted by the intraocular fluids on the coats of the eyeball. Normal IOP : 10-21mmHg Maintained by dynamic equilibrium between the formation and outflow of the aqueous humour. Factors influencing IOP can be grouped as under: Local factors General factors MAINTENANCE OF IOP

13. CLASSIFICATION OF GLAUCOMA Congenital/developmental glaucoma Primary congenital glaucoma (without associated anomalies) Developmental glaucoma (with associated anomalies ) Primary adult glaucoma Primary open -angle glaucoma (POAG) Primary angle -closure glaucoma (PACG) Primary mixed mechanism glaucoma Secondary glaucoma

14. PATHOGENESIS OF GLAUCOMATOUS OCULAR DAMAGE The death of retinal ganglion cells (RGCs) in a typical pattern which results in characteristic optic disc appearance and specific visual field defects . Some pathological events block the transport of growth factors ( neurotrophin ) from brain to RGC Blockage initiates the damaging cascades and the cell is unable to maintain its normal function Cell undergoes apoptosis and involves adjacent cells RGC death associated with loss of retinal nerve fibers Characteristic of disc changes and specific visual field defects become apparent over the time

15. ETIOLOGICAL FACTORS Primary insults Raised IOP (Mechanical theory) Pressure independent factors Failure of autoregulatory mechanism of blood flow Vasospasm ( migranous headache) Systemic hypotension Other factors (acute blood loss and abnormal coagulability profile) Secondary insults ( Excitotoxicity theory) Neuronal degeneration is believed to be driven toxic factors such as glutamate, oxygen-free radicals, or nitric oxide which are released when RGCs undergo death due to primary insults.

16. GLAUCOMATOUS OPTIC NEUROPATHY

17. A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

18. A group of diverse disorders in which abnormal high IOP results due to developmental abnormalities of the angle of anterior chamber obstructing the drainage of aqueous humour . Developmental glaucoma preferred in glaucoma that occur after several years of birth . Types: Primary congenital/developmental glaucoma (PCG). Developmental glaucoma with associated congenital ocular anomalies OR systemic anomalies. A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

19. 1. PRIMARY CONGENITAL / DEVELOPMENTAL GLAUCOMA Depending upon the age of onset the developmental glaucoma are termed as : Newborn glaucoma (true congenital glaucoma)[ 40% of cases] When IOP raised during intrauterine life and child is born with ocular enlargement. Infantile glaucoma [55% of cases] When the disease manifests prior to the child’s third birthday Juvenile glaucoma (Juvenile open-angle glaucoma/POAG )[5%] Develop pressure rise after 3 years but before adulthood. Bupthalmos (bull-like eyes) = The eyeball enlarges prior to age of 3 years due to retention of aqueous humour; thus ‘hydropthalmos’ suggested A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

20. PATHOGENESIS Maldevelopment, from neural crest derived cells, of trabeculum including the iridotrabecular junction (trabeculodysgenesis ) is responsible for impaired aqueous outflow resulting in raised IOP . Clinically , it is characterized by absence of the angle recess with the iris into the surface of trabeculum as follows : Flat iris insertion : Iris inserts flatly and abruptly into the thickened trabeculum either at anterior or posterior to scleral spur. Possible to visualize a portion of ciliary body and scleral spur . C oncave iris insertion : It in superficial iris tissue sweeps over the iridotrabecular junction and the trabeculum and, thus, obscures the scleral spur and ciliary body. A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

21. CLINICAL FEATURES Lacrimation, photophobia and blepharospasm Classic triad of congenital glaucoma Corneal signs Corneal edema Corneal enlargement [>13mm confirms enlargement] Tears and breaks in Descemet’s membranes (Haab’s striae) [appears as lines with double contour] Sclera : Thin and appears blue due to underlying uveal tissue. Anterior chamber : Becomes deep Iris : Iridodonesis and atrophic patches in late stage. Lens : Flat due to stretching of zonules and subluxate backward. Optic disc : Variable cupping and atrophy especially after third year. IOP : Raised which is neither marked nor acute. Axial myopia : Increase in axial length leading to anisometropic amblyopia. A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

22. EXAMINATION A complete examination under general anesthesia (EUA) should be performed. Measurement of IOP Perkin’s applanation tonometer (very low scleral rigidity in children) Schiotz tonometer Measurement of corneal diameter by calipers. Slit-lamp examination. Ophthalmoscopy to evaluate optic disc. Gonioscopic examination The angle of anterior chamber reveals trabeculodysgenesis A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

23. DIFFERENTIAL DIAGNOSIS Cloudy cornea Trauma/ Interstitial keratitis/ Corneal endothelial injury Large cornea Megalocornea/ Sclerocornea/ High myopia Lacrimation Congenital nasolacrimal duct blockage/ Corneal abrasion/ Meesman’s corneal dystrophy Photophobia Keratitis / Uveitis Raised IOP Retinoblastoma/ Secondary congenital glaucoma (rubella/aniridia/Sturge-Weber syndrome) Optic disc changes Pit/ Hypoplasia/ Tilted disc/ Large physiological cup A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

24. TREATMENT Medical treatment (acetazolamide, beta blocker) Surgical procedures Incisional angle surgery Internal approach (goniotomy)[85% success rate] Barkan’s goniotomy knife (approximately 75 o ) External approach (trabeculectomy) Harm’s trabeculotome Filteration surgery Trabeculectomy with antimetabolites gives good results. Combined trabeculectomy and trabeculectomy with antimetabolites Glaucoma drainage devices (GDD) Required in incalcitrant cases. A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

25. Technique of goniotomy A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

26. 2. 1 DEVELOPMENTAL GLAUCOMAS WITH ASSOCIATED OCULAR ANOMALIES Glaucoma associated with iridodysgenesis Glaucoma associated with iridocorneal dysgenesis 2.2 DEVELOPMENTAL GLAUCOMAS WITH ASSOCIATE SYSTEMIC ANOMALIES Glaucoma associated with chromosomal disorders Glaucoma associated with ectopia lentis syndrome Glaucoma associated with phakomatosis Glaucoma associated with metabolic syndromes A. CONGENITAL AND DEVELOPMENTAL GLAUCOMA

27. B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

28. Chronic simple glaucoma of adult onset. Typical characteristics are: Slowly progressive raised IOP (>21mmHg on at least a few occasion) associated with, Open normal appearing anterior chamber angle Characteristic optic disc cupping Specific visual field defects Etiopathogenesis Predisposing and risk factors Pathogenesis of IOP Pathogenesis of optic neuropathy (refer RGC death) B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

29. ETIOLOGY & PATHOPHYSIOLOGY PREDISPOSING AND RISK FACTORS HEREDITY - polygenic inheritance, 4% risk in the offspring of patients AGE - risk  with  age RACE - more severe in black MYOPES - nearsighted person DIABETICS - higher prevalence SMOKING - higher risk HIGH BLOOD PRESSURE THYROTOXICOSIS - does not cause  IOP, but prevalence more in Graves’ ophthalmic patients than the normals  IOP  AQUEOUS OUTFLOW FACILITY  RESISTANCE TO AQUEOUS OUTFLOW TRABECULAR MESHWORK THICKENING & SCLEROSIS ABSENCE OF GIANT VACUOLES (CANAL OF SCHLEMM) CAUSE UNCERTAIN UNCONTROLLED B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

30. PATHOGENESIS OF RISE OF IOP Rise of IOP due to reduced in aqueous flow facility that is caused by increased resistance to aqueous outflow It is caused by: Thickening and sclerosis of trabecular meshwork with faulty collagen tissue Narrowing of intratrabecular spaces Deposition of amorphous material in the juxtacanalicular space Collpase of Schlemm’s canal B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

31. SYMPTOMS Asymptomatic Headache and eye ache Scotoma (defects in visual field) Difficulty in reading and close work Delayed dark adaptation Significant loss of vision and blindness B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG) SIGNS Anterior chamber signs Sluggish pupil reflex Cornea show slight haze A low (<555µm) central corneal thickness (CCT) Intraocular pressure changes Optic disc changes Fundus examination (Slit lamp biomicroscopic examination) Confocal scanning laser topography (Heidelberg retinal tomography/HRT) Optical coherence tomography (OCT) Visual field defects

32. LARGE CU P - 0.6 or more (Normal cup size – 0.3 to 0.4) may occur d/t concentric expansion SPLINTER HAEMORRHAGES  present on/near optic disc margin PALLOR AREAS - present on disc ATROPHY OF RETINAL NERVE FIBRE LAYER - seen with red free light 1. EARLY GLAUCOMATOUS CHANGES Reveals one or more of the following signs: NORMAL EARLY CHANGE B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

33. MARKED CUPPING - cup size 0.7 to 0.9, excavation may even reach the disc margin THINNING OF NEURORETINAL RIM - seen as a crescentric shadow adjacent to the disc margin NASAL SHIFTING OF RETINAL VESSELS - appearance of being broken off at the margin – BAYONETTING SIGN 2. ADVANCED GLAUCOMATOUS CHANGES Reveals one or more of the following signs: NORMAL LATE CHANGE B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

34. PULSATIONS OF THE RETINAL ARTERIOLES - may be seen at the disc margin (a PATHOGNOMIC SIGN of glaucoma), when IOP is very high LAMELLAR DOT SIGN  pores in the lamina cribrosa are slit-shaped and are visible up to the margin of the disc 2. ADVANCED GLAUCOMATOUS CHANGES Reveals one or more of the following signs: NORMAL LATE CHANGE B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

35. As the damage progresses, all the NEURAL TISSUE of the disc is destroyed and the OPTIC NERVE HEAD appears white & excavated 3. GLAUCOMATOUS OPTIC ATROPHY Reveals one or more of the following signs: NORMAL OPTIC ATROPHY B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

36. VISUAL FIELD DEFECTS - usually run parallel to the changes at optic nerve head & progresses if IOP is not controlled SR F & I R F - supe ri o r and inf e ri o r radiating fibres from nasal half P MB - P A P I L L OM A C U L A R B U N D L E from macular area SAF & IAF - superior & inferior arcuate fibres from the temporal half ANATOMICAL BASIS OF FIELD DEFECTS DISTRIBUTION OF RETINAL NERVE FIBRES B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

37. VISUAL FIELD DEFECTS - usually run parallel to the changes at optic nerve head & progresses if IOP is not controlled From peripheral part – lie deep in the retina but occupy the most peripheral (superficial) part of the optic disc Fibres originating closer to the nerve head – lie superficially and occupy a more central (deep) portion of the disc. EARLY LOSS IN THE VISUAL FIELD REGIONS RETENTION OF CENTRAL VISION TILL END ANATOMICAL BASIS OF FIELD DEFECTS ARRANGEMENT OF NERVE FIBRES WITHIN OPTIC NERVE HEAD ARCUATE FIBERS (SAF & IAF ) - occupy the superior & inferior temporal half of optic nerve head – most sensitive to damage MACULAR FIBRES - most resistant to the glaucomatous damage B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

38. VISUAL FIELD DEFECTS - usually run parallel to the changes at optic nerve head & progresses if IOP is not controlled PROGRESSION OF FIELD DEFECTS I S OPTER CONTRACTION - mild generalized constriction of central as well as peripheral field EARLIEST VISUAL FIELD DEFECT B ARING OF BLIND SPOT - exclusion of the blind spot from the central field d/t inward curve of the outer boundary of 30° central field S MALL WING-SHAPED PARACENTRAL SCOTOMA - appear below or above the blind spot in BJERRUM'S AREA EARLIEST CLINICALLY SIGNIFICANT FIELD DEFECT S EIDEL’S SCOTOMA - “ Sickle-shaped ” in time, paracental scotoma joins the blind spot B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

39. A RCUATE OR BJERRUM’S SCOTOMA - formed by extension of Seidel’s scotoma in an area either above or below the fixation point to reach the horizontal line R ING / DOUBLE ARCUATE SCOTOMA - develops when the two arcuate scotomas join together R OENNE'S CENTRAL NASAL STEP - two arcuate scotomas run in different arcs and meet to form a sharp right-angled defect at the horizontal meridian P ERIPHERAL FIELD DEFECTS - can appear in early and late stages A DVANCED FIELD DEFECTS - eventually only a small island of central vision ( TUBULAR VISION ) are left B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

40. B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

41. DIAGNOSTIC FACTORS CRITERIA to diagnose EARLY , MODERATE and SEVERE glaucomatous field defects B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

42. TONOMETRY - measures the IOP TWO BASIC TYPES OF TONOMETERS: INDENTATION (IMPRESSION) 2. Schiotz Tonometer APPLANATION 1. Goldmann Tonometer B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

43. IOP CHANGES Exaggeration of diurnal variation Diurnal variation test (every 3-4hr for 24hr) IOP falls during the evening contrary to PACG Morning rise in IOP : 20% of cases Afternoon rise in IOP : 25% of cases Biphasic rise in IOP : 55% of cases Variation of over 5mmHg is suspicious Variation of over 8mmHg is diagnostic In late stages, ranges between 30-45 mmHg. B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

44. DIURNAL VARIATION TEST - useful in detection of early cases A – Normal slight morning rise B – Morning rise seen in 20% cases C – Afternoon rise seen in 25% D – Biphasic variation seen in 55% SLIT-LAMP EXAMINATION - to rule out causes of 2° Open Angle Glaucoma WATER DRINKING TEST - eyes with glaucoma with greater response to water drinking 8 hours fasting, then baseline IOP Patient drinks 1L of water, then IOP noted q 15min for 1 hour Rise of 8 mmHg or more ( DIAGNOSTIC ) NERVE FIBRE LAYER ANALYZER - to detect damage in retinal nerve fibres B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

45. PERIMETRY - detect visual field defects TWO CLASSIFICATIONS OF PERIMETERS: GOLDMANN’S PERIMETER 1. Manual Perimeter LISTER’S PERIMETER 2. Automated Perimeter HUMPHREY FIELD ANALYSER ADVANTAGES OF AUTOMATED: Level of precision & consistency data storage capability & ease Statistical comparison B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

46. GONIOSCOPY - primary importance in POAG is to rule out other forms of glaucoma GOLDMANN’S GONIOLENS & TECHNIQUE OF GONIOSCOPY APPLICATIONS OF GONIOSCOPY: C la s s ificatio n of gla u c o m a int o open ang l e and closed angle based on configuration of the angle Localization of foreign bodies, abnormal blood vessels or tumors in the angle. D e m onst r a t io n of e x t ent of pe r iphe r al ante r ior synechiae and hence planning of glaucoma surgery Direct goniolens is used during goniotomy B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

47. SHAFFER’S SYSTEM OF GRADING THE ANGLE WIDTH MOST COMMONLY USED B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

48. HEIDELBERG RETINAL TOMOGRAPHY B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

49. OPTICAL COHERENCE TOMOGRAPHY (OCT) B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

50. DIFFERENTIAL DIAGNOSIS Primary open-angle glaucoma Raised IOP more than 21mmHg associated with definite glaucomatous optic disc cupping and visual field defects. Ocular hypertension IOP constantly more than 21mmHg but no optic disc and visual field changes . Normal/low tension glaucoma Typical glaucomatous disc cupping with or without visual field changes is associated with IOP less than 21mmHg. B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

51. GRADING (Severity of glaucoma damage) Degree Description Mild Characteristic optic-nerve abnormalities are consistent with glaucoma but the with the normal visual field. Moderate Visual-field abnormalities in one hemi-field and not within 5 degrees of fixation. Severe Visual-field abnormalities in both hemifields and within 5 degrees of fixation. B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

52. MANAGEMENT General considerations Aim : To lower IOP to a level visual loss does not occur. Baseline data need to gather for future progress should include: Visual acuity Slit lamp examination of anterior chamber Tonometry Central corneal thickness Optic disc evaluation Gonioscopy Visual field charting Evaluate grading of glaucoma B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

53. MANAGEMENT Therapeutic choices Medical therapy Identification of target pressure Single drug therapy Combination therapy Monitoring therapy Argon or diode laser trabeculectoplasty (ALT) Complications : Transient acute rise of IOP Transient inflammation Hemorrhage/uveitis Filteration surgery B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

54. TREATMENT REGIMES Single drug therapy Prostaglandin analogues ( latanaprost / travoprost ) Topical beta-blockers (timolol/ betaxolol / levobunolol ) Adrenergic drugs (epinephrine hydrochloride/ brimonide ) Dorzolamide Pilocarpine Combination topical therapy (timolol + pilocarpine) Role of oral carbonic anhydrase inhibitors in POAG ( acetozalamide ) Hyperosmotic agents (mannitol) Neuroprotective agents B. 1. PRIMARY OPEN -ANGLE GLAUCOMA (POAG)

55. OCULAR HYPERTENSION Patient with IOP constantly more than 21mmHg but no optic disc and visual field changes. ‘Glaucoma suspect’ is an adult having normal open angle on gonioscopy and anyone of the following signs in at least one eye: Elevated IOP Suspicious disc changes in the form of asymmetric or narrowing of neuroretinal rim or a disc hemorrhage, Visual fields consistent with glaucomatous damage.

56. RISK FACTOR OF POAG IN OCULAR HYPERTENSION PATIENTS High risk reported by Ocular Hypertension Study (OHTS) and European Glaucoma Prevention Study (EGPS) are; IOP consistently >30mmHg CCT <555µm Vertical cup disc ratio of >0.7 Increase age Increased pattern standard deviation on Humphrey visual field test Disc hemorrhages (splinter hemorrhages over/near the disc) Others Family history Fellow eye of the unilateral POAG Other ocular conditions (myopia/steroid responder) Systemic risk factors (DM/HTN/hypothyroidism/ migranous headache)

57. NORMAL TENSION GLAUCOMA Low tension glaucoma is labelled when typical glaucomatous disc changes with an intraocular field defects are associated with IOP below 21 mmHg. Etiopathogenesis Raynaud phenomenon Migraine Nocturnal systemic hypotension Overtreated systemic hypertension Reduced blood flow velocity in the ophthalmic artery

58. B . 2. PRIMARY ANGLE- CLOSURE GLAUCOMA (PACG)

59. B . 2. PRIMARY ANGLE- CLOSURE GLAUCOMA (PACG) A type of primary glaucoma, (–) obvious systemic or ocular cause Increase IOP occur due to blockage of the aqueous humour outflow Closure of a narrower angle of the anterior chamber Sudden increase in IOP

60. ETIOLOGY & PATHOPHYSIOLOGY I. ANATOMICAL FACTORS HYPERMETROPIA with shallow anterior chamber Iris-lens DIAPHRAGM placed anteriorly NARROW ANGLE of anterior chamber, which may be d/t: Small eyeball Relatively large size of the lens & smaller diameter of the cornea Bigger size of the ciliary body II. GENERAL FACTORS AGE GENDER RACESEASON FAMILY HISTORY TYPE OF PERSO- NALITY PREDISPOSING RISK FACTORS The following factors may PRECIPITATE an attack: DIM ILLUMINATION EMOTIONAL STRESS MYDRIATIC DRUGS like Atropine, Tropicamide PRECIPITATING FACTORS INCREASED AMOUNT OF APPOSITION B/W IRIS ANTERIORLY PLACED LENS WITH CONSIDERABLE PRESSURE NORMAL PUPIL MILD PUPIL DILATATION

61. Pathogenesis of rise in IOP Mydriasis effect Mid dilated pupil Relative pupil block Iris bombe formation Appositional angle closure

62. RELATIVE PUPIL BLOCK AQUEOUS HUMOR COLLECTS IN THE POSTERIOR CHAMBER PUSHES THE PERIPHERAL FLACCID IRIS ANTERIORLY IRIS BOMBE APPOSITIONAL ANGLE CLOSURE SYNECHIAL ANGLE CLOSURE ATTACK OF  IOP MAY LAST LONGER ACUTE PACG CHRONIC PACG Results from the following CIRCUMSTANCES: CREEPING SYNECHIAE SUBACUTE PACG ATTACKS MIXED MECHANISM

63. Classification (ISGEO Classification) (International Society of Geographical and Epidemiological Ophthalmology) Primary angle closure suspect (PACS) Primary angle closure (PAC) Primary angle closure glaucoma (PACG ) T raditional clinical classification Latent primary angle-closure glaucoma Subacute (intermittent) primary angle-closure glaucoma Acute primary angel-closure glaucoma Chronic primary angle-closure glaucoma

64. VAN HERICK METHOD OF SLIT-LAMP GRADING A – Grade IV B – Grade III C – Grade II D – Grade I E – Grade GRADES: Grade 4 ( WIDE OPEN ANGLE ) PACD = 3/4 to 1 CT Grade 3 ( MILD NARROW ) PACD = ¼ to ½ CT Grade 2 ( MODERATE NARROW ) PACD = ¼ CT Grade 1 ( EXTREMELY NARROW ) PACD < ¼ CT Grade ( CLOSED ANGLE ) PACD Nil

65. 1. PRIMARY ANGLE-CLOSURE SUSPECT (PACS) PACS can be considered analogous to the term ‘latent primary angle-closure glaucoma’ of clinical classification. Symptoms are absent in this stage. Presenting situations for diagnosis include: Suspicious clinical signs on routine ocular examination Eclipse sign Slit-lamp biomicroscopic signs Van Herick slit lamp grading of the angle Fellow eye of the patients presenting with acute attack of PAC Glaucoma screening programme.

66. DIAGNOSTIC TEST IOP measurement Gonioscopy Ultrasonic biomicroscopy Anterior segment OCT Optic disc evaluation Visual field analysis D IAGNOSTIC CRITERIA FOR PACS Gonioscopy with irido -trabecular contact greater than 270 degree angle and no peripheral anterior synechia (PAS absent) IOP normal No optic changes Normal visual fields

67. MANAGEMENT Provocative test Prone-darkroom Mydriatic provocative Inferences from provocative test are: Positive indicates that angle is capable od spontaneous closure. Negative in the presence of occludable angles on gonioscopy does not rule out a possibility of spontaneous closure. So patient should be warned of possible symptoms of an acute attack of PAC . TREATMENT Prophylactic laser iridotomy Periodic follow up

68. 2. PRIMARY ANGLE CLOSURE (PAC) Considered to comprise following entities of clinical classification: Subacute primary angle closure Acute PAC Chronic PAC (asymptomatic) D efining criteria for PAC I rido -trabecular contact noted on gonioscopy in greater than 270 degree angle I OP elevated and/or peripheral anterior synechiae (PAS) present O ptic disc normal V isual field normal I mpression = Angle is abnormal either in function and/or structure.

69. 3. PRIMARY ANGLE-CLOSURE GLAUCOMA (PACG) Pathogenesis Gradual synechial closure of the angle of anterior chamber. Untreated patients with PAC may over the period covert to PACG with or without history of subacute/acute attack of PAC. Clinical features Subacute and acute PACG C hronic PACG I OP constantly raised E yeball no congestion and painless except in post acute angle closure cases where eyes may be congested and irritable. O ptic disc shows glaucomatous cupping V isual field defects similar to POAG occur G onioscopy reveals >270o of angle closure along peripheral anterior synechiae(PAS)

70. Defining criteria for PACG Irido -trabecular contact greater than 270o of angle P AS are formed I OP elevated O ptic disc show glaucomatous damage V isual fields show typical glaucomatous defects Treatment Laser iridotomy Trabeculectomy Prophylactic laser iridotomy

71. ABSOLUTE PRIMARY ANGLE-CLOSURE PACG, if untreated, gradually passes into the final phase of absolute glaucoma. Clinical features Painful blind eye Perilimbal reddish blue zone Caput medusae Cornea clear but insensitive; slowly progress into bullous keratopathy/filamentary keratitis Anterior chamber very shallow Iris become atrophic Pupil fixed and dilated and gives a greenish hue. Optic dish shows glaucomatous optic atrophy IOP is high, eyeball become stony hard

72. MANAGEMENT Retrobulbar alcohol injection 1ml of 2% xylocaine followed after 5-10 minutes by 1ml of 80% alcohol It destroys ciliary ganglion Destruction of secretory ciliary epithelium To lower IOP Enucleation of eyeball COMPLICATIONS Corneal ulceration Staphyloma formation Atrophic bulbi

73. CLINICAL MANIFESTATIONS: INDICATES DECREASED AXIAL ANTERIOR CHAMBER DEPTH 1. LATENT PRIMARY ANGLE-CLOSURE GLAUCOMA - “ Glaucoma suspect ” Eyes with shallow anterior chamber with an occludable angle SYMPTOMS - absent ECLIPSE SIGN - elicited by shining a penlight across the anterior chamber from temporal side, noting a shadow on the nasal side

74. CLINICAL MANIFESTATIONS: LATENT PRIMARY ANGLE-CLOSURE GLAUCOMA  “ Glaucoma suspect ” GONIOSCOPIC EXAMINATION  it shows very narrow angle (SHAFFER GRADE 1) SLIT-LAMP BIOMICROSCOPIC SIGNS: a.  axial anterior chamber depth b.Convex shaped iris lens diaphragm c. Close proximity of the iris to cornea in the periphery

75. CLINICAL MANIFESTATIONS: 2. SUBACUTE OR INTERMITTENT PACG During PE, eye is white & not congested All the signs described in LATENT PACG can be elicited in this phase ALSO CLINICAL COURSE - if without treatment , may follow any of the following: Attack of ACUTE PACG CHRONIC PACG without passing through acute stage

76. CLINICAL MANIFESTATIONS: 3. ACUTE ANGLE-CLOSURE GLAUCOMA Attack of Acute PACG occurs d/t a sudden total angle closure leading to SEVERE RISE in IOP SIGHT THREATENING EMERGENCY! SYMPTOMS PAIN - sudden onset of very severe pain that radiates along the CN-V branches NAUSEA, VOMITING, PROSTRATIONS Rapid progress of VISION LOSS  also with redness, photophobia & lacrimation ( PRESENT IN ALL CASES ) PAST HISTORY - ~5% (+)Hx of typical previous transient attacks of subacute angle-closure glaucoma

77. CLINICAL MANIFESTATIONS: ACUTE ANGLE-CLOSURE GLAUCOMA SIGNS LIDS - may be edematous CONJUNCTIVA - congested CORNEA - edematous & insensitive ANTERIOR CHAMBER - very shallow ANGLE OF ANTERIOR CHAMBER - closed completely ( SHAFFER GRADE0 ) IRIS - may be discoloured NOTE CILIARY CONGESTION , CORNEAL EDEMA & MIDDILATED PUPIL DISCOLOURED IRIS VERY SHALLOW – ANTERIOR CHAMBER

78. CLINICAL MANIFESTATIONS: 4. CHRONIC PACG Similar to POAG, EXCEPT that the angle in Chronic PACG is narrow IOP - constantly raised EYEBALL - it is usually remains white (without congestion) & PAINLESS OPTIC DISC - may show cupping VISUAL FIELD DEFECTS - like POAG GONIOSCOPY - variable degree of angle closure PAINLESS EYEBALL

79. PERIPHERAL IRIDECTOMY Indications Treatment of all stages of primary angle-closure glaucoma Prophylaxis of glaucoma Technique Anterior limbal incision is done at the is done about 4mm Prolapse of peripheral iris by pressure at posterior lip of the incision Small full thickness piece of iris is excised by de Wecker’s scissors Iris is reposited back and wound is closed Subconjunctival injection of dexamethasone 0.25 ml and gentamicin 0.5 ml is given Putching of eye with sterile eye pad and plaster

80. C. SECONDARY GLAUCOMA

81. A group of disorders in which rise of IOP is associated with some primary ocular/ systemic disease. Therefore, clinical features comprises that of primary disease and that due to effects of raised IOP. Classification Depending upon mechanism of rise in IOP Secondary open angle glaucoma in which aqueous outflow may be blocked by; Pretrabecular membrane Trabecular clogging Edema and scarring Post-trabecular elevated episcleral venous pressure Secondary angle closure glaucoma which may/may not be associated with pupil block.

82. Depending upon causative primary disease, secondary glaucomas are named as follows: Lens-induced ( Phacogenic ) glaucoma Inflammatory glaucoma Pigmentary glaucoma Neovascular glaucoma Glaucoma associated with iridocorneal endothelial syndromes Pseudo exfoliative glaucoma Glaucoma associated with intraocular hemorrhage Steroid-induced glaucoma Traumatic glaucoma Glaucoma -in-aphakia Glaucoma associated with intraocular tumours

83. Phacomorphic Glaucoma Phacolytic glaucoma (Lens protein glaucoma) Lens particle glaucoma Phacoantigenic glaucoma Causes : Intumescent lens – swollen cataractous lens (rapid maturation of cataract or traumatic rupture of capsule Ant. subluxation/dislocation of the lens & spherophakia congenital smaller, more spherical optic lens cause for phacotopic glaucoma   PATHOGENESIS Trabecular meshwork is clogged by lens protein, macrophages which have phagocytosed lens protein & inflammatory debris Leakage of lens proteins occurs through intact capsule in hypermature cataractous lens   PATHOGENESIS Trabecular meshwork is blocked by lens particles floating in aqueous humour After accidental/planned ECCE (Extracapsular Cataract Extraction) or following traumatic rupture of lens Fulminating acute inflammatory reaction due to Ag-Ab reaction Same mechanism & management with acute inflammatory glaucoma Typical finding – granulomatous inflammation in involved eye after it goes surgical trauma PATHOGENESIS : Swollen len pushes iris forward & obliterates the angle Further increase iridolenticular contact (pupillary block & iris bombe) PATHOGENESIS : There is preceding distruption of lens capsule by ECCE, penetrating injury or leaks of protein from capsule Trabecular meshwork is clogged by both inflammatory cells & lens particles

84. Phacomorphic Glaucoma Phacolytic glaucoma (Lens protein glaucoma) Lens particle glaucoma Phacoantigenic glaucoma CLINICAL FEATURES As in acute congestive glaucoma with features of primary angle closure glaucoma Lens is always cataractous & swollen CLINICAL FEATURES Features of acute congestive glaucoma Pseudohypopyon Open ant. Chamber ( gonioscopy ) CLINICAL FEATURES Symptoms of acute rise in IOP assoc. lens particles in anterior chamber     MANAGEMENT Medical treatment – IV mannitol, systemic acetazolamide & topical BB Surgical – laser iridotomy (breaking closure-angle attack) Cataract extraction with implantation of PCIOL MANAGEMENT Extraction of hypermature cataractous lens MANAGEMENT Irrigation-aspiration of lens particles from ant. chamber MANAGEMENT Treatment of iridocylitis ( streroid & cycloplegics ) Irrigation-aspiration of lens matter from ant. Chamber

85. GLAUCOMA DUE TO UVEITIS IOP raised due to inflammation of uveal tissue (iridocyclitis)

86. NON SPECIFIC INFLAMMATORY GLAUCOMA Acute Open Angle Inflammatory Glaucoma Chronic Open Angle Inflammatory Glaucoma Angle closure inflammatory glaucoma Mechanism r Trabecular clogging Trabecular oedema Prostaglandin induced rise in IOP Mechanism Chronic trabeculitis and trabecular scarring Mechanism 2’ angle closure with pupil block (due to annular synechiae or acclusio pupillae – iris bombe) 2’ angle closure without pupil block (organization of inflammatory debris in the angle causing pulling of iris over the trabeculum during contraction – gradual & progressive synechiae angle closure + increased IOP) Clinical features Features of acute iridocylitis + increased IOP + open angle of ant. chamber Returns to normal after acute episode of inflammation Clinical features Raised IOP, open angle, no active inflammation Signs of prev episode of uveitis present Glaucomatous disc changes & field defects Clinical features Raised IOP, seclusion papillae, iris bombe, shallow ant. Chamber   Management Treat iridocylitis Medical therapy to lower IOP (hyperosmotic agents, acetazolamide, BB) Treatments Medical therapy – topical BB , CAI & alpha agonist (avoid pilocarpine & PGs) Trabeculectomy Cyclodestructive procedure ( cycloiodide ) Management Prophylaxis (treat acute iridocylitis – local steroids & atropine) Curative – medical therapy to reduced IOP, surgical or laser iridotomy in pupil block without angle closure and filtration surgery in presence of angle closure

87. SPECIFIC HYPERTENSIVE UVEITIS SYNDROMES Fuchs’ Uveitis Syndrome Glaucomatocyclitic Crisis Clinical Features Heterochromia of iris Diffuse stromal iris atropy (moth-eaten appearance) Fine stellate KPs at the back of cornea Faint aqueous flare Absence of posterior synechiae Rubeosis iridis , associated with neovascularization of anterior chamber angle Early development of complicated cataract and secondary glaucoma (open angle type) Clinical Features Posner schlossman syndrome Recurrent unilateral attack of acute rise IOP without shallowing of anterior chamber Fine KPs at the back of cornea, without posterior synechiae Epithelial edema of cornea Dilated pupil White eye (no congestion) Affect young adult Treatment Topical corticosteroid Cycloplegics Associated glaucoma treated as for POAG Treatment Antiglaucoma drugs Topical steroid

88. PIGMENTED GLAUCOMA NEOVASCULAR GLAUCOMA GLAUCOMA ASSOCIATED WITH INTRAOCULAR TUMOR Clogging up of trabecular meshwork occurs by pigment particles Intractable glaucoma due to formation of neovascular membrane involving the angle of anterior chamber Malignant melanoma (iris, choroid, ciliary body) Retinoblastoma Pathogenesis Pigment released by mechanical rubbing of posterior pigment layer of iris with the zonular fibrils Etiology (retinal ischemia) Proliferative diabetic retinopathy Central retinal vein occlusion Sickle cell retinopathy Easles ’ disease Chronic intraocular inflammation Intraocular tumor Long standing retinal detachment Central retinal artery occlusion Mechanism Trabecular block due to clogging of tumor cells Neovascularization of the angle Venous stasis Abgle closure Clinical features Young myopic males Similar to primary open angle glaucoma Deposition of pigment granules in the anterior segment structure Gonioscopy shows pigment accumulation along the Scwalbe’s line Iris translumination shows radial slit like Clinical features Pre-glaucomatous stage: rubeosis iridis Open-angle glaucoma: formation of a pretrabecular neovascular membrane (NVM) Secondary ACG: goniosynechiae - contracture of the NVM (zipper angle closure) Treatment As primary open angle glaucoma Treatment Panretinal photocoagulation Medical therapy, conventonal filtration surgery Glaucoma drainage device- artificial filtration shunt (Seton operation)

89. REFERENCES Comprehensive Opthalmology , 6 th Edition, AK Khurana, New Age International publisher, page 219-256