Primary Angle Closure Glaucoma- Saral

Presentation on Primary Angle Closure Glaucoma

1. PRIMARY ANGLE CLOSURE GLAUCOMA SARAL LAMICHHANE MBBS IV Year/Roll-61

2. Introduction Glaucoma refers to a group of disorders characterized by progressive optic neuropathy resulting to characteristic visual field defects; raised Intraocular Pressure(IOP) being the most important risk factor. Normal Tension Glaucoma(NTG/LTG) also exist Normal IOP = 10 – 21 mmHg (Mean: 16 2.5 mmHg)

3. Classification: 1) Congenital & Developmental Glaucoma 2) Primary Adult Glaucoma : (No obvious systemic/ocular cause of rise in IOP) a) Primary Open Angle Glaucoma (POAG) b) Primary Angle Closure Glaucoma (PACG) c) Primary Mixed Mechanism Glaucoma 3) Secondary Glaucoma: (Rise of IOP with some primary ocular or systemic disease)

4. Primary Angle Closure Glaucoma Primary glaucoma in which rise in Intraocular Pressure (IOP) occurs due to blockage of aqueous humor outflow by closure or narrower angle of the anterior chamber. Predisposing Risk Factors : 1) Anatomic Factors: - Hyperopic eye - Iris-lens diaphragm placed anteriorly - Narrow angle of anterior chamber - Plateau Iris Configuration

5. 2) General Factors: - Age: 5 th Decade onwards - Sex: Females > Males - Rainy Season - Family History - Race (Caucasians, South East Asians) - Heredity: Family history Precipitating factors : - Dim illumination - Emotional Stress - Use of mydriatics : Atropine, Tropicamide , Cyclopentolate

6. Aqueous humor secretion from Non-pigmented epithelium of Ciliary processes Posterior Chamber Pupil Anterior Chamber: Conventional ( Trabecular ) Pathway : 90% Trabecular Meshwork Canal of Schlemm Collector Channels Episcleral Vessels Uveoscleral Pathway: Trabecular Meshwork Ciliary body Suprachoroidal space Venous Drainage

7. Mechanism: Relative Pupil Block - Iris bombe formation - Appositional Angle Closure - Synechial angle closure Plateau Iris Configuration Anteriorly positioned ciliary displacing the iris anteriorly Phacomorphic mechanism - Abnormal lens

8. Symptoms: Eye redness Eyeache Headache Nausea/Vomiting Blurring of vision Colored halos Signs: Circumcorneal congestion Corneal edema, hazy cornea Very shallow anterior chamber (Eclipse Sign) Iridocorneal angle closure as seen in gonioscopy Raised Intraocular pressure Reduced visual acuity Vertically oval & mid-dilated pupil

9. Progression Primary Angle Closure Suspect: No clinical signs/symptoms Irido-trabecular contact in greater than 270 Intraocular Pressure (IOP) Normal No Peripheral Anterior Synechiae (PAS) Optic disc & Visual Field Normal

10. Angle Closure: Irido-trabecular contact in greater than 270 Mild clinical symptoms/signs IOP may or may not be raised PAS may or may not be present Optic disc & Visual Field Normal

11. Acute Angle Closure: Typical clinical symptoms/signs present Irido-trabecular contact greater than 270 IOP raised PAS present Optic disc & Visual field normal

12. Angle Closure Glaucoma: Typical clinical symptoms/signs present Irido-trabecular contact greater than 270 IOP raised, PAS formed Optic Nerve shows glaucomatous damage Characteristic visual field defect

13. Optic Nerve Changes Glaucomatous cupping: Increase in Cup : Disc ratio  0.6 Normal CDR = 0.3-0.4 Cup Asymmetry: CDR difference > 0.2 in two eyes Neuroretinal rim thinning: Cup to Disc distance ISNT Rule- Thickness of Inferior rim> Superior rim > Nasal rim> Temporal rim Thinning usually in same sequence

14. Bayonetting Sign: Z shaped bending of vessels at the margin Disc hemorrhages: flame shaped Lamellar dot sign: pores in lamina cribrosa slit shaped & visible upto disc margin Peripapillary chorioretinal atrophy

15. Visual Field Defect Isopter contraction Baring of blind spot Paracentral Scotoma Siedel’s Scotoma Superior Arcuate or Bjerrum’s Scotoma Inferior Arcuate or Bjerrum’s Scotoma Ring or Double Arcuate Scotoma Roenne’s central nasal step Tubular Vision

16. Diagnosis History: Symptoms Clinical Examination: Signs Diagnostic tests: Tonometry : IOP measurement Gonioscopy : Angle structures Slit lamp biomicroscopy Ultrasonic biomicroscopy Fundoscopy Visual Field Analysis

17. Management Principle: Immediate medical therapy (Lower IOP) Definitive treatment Prophylaxis of fellow eye Long term glaucoma surveillance and IOP management of both eyes

18. Immediate medical therapy: Intravenous line access Systemic hyperosmotic agents: Mannitol 20% iv 1g/kg within 30-45 mins Glycerol oral 1g/kg of 50% solution in lemon juice Systemic Carbonic Anhydrase Inhibitors: Acetazolamide 500mg oral stat followed by 250 mg tds Analgesics/ Antiemetics

19. Topical Antiglaucoma medication: Beta- Blockers: Timolol 0.5%, Betaxolol 0.5%, Levobunalol 0.5% Prostaglandin analogue: Latanoprost (0.005%), Bimatoprost Alpha-1 Adrenergic agonist: Brimonidine (0.1-0.2%) Pilocarpine 2% qid after 1 hour Steroid eye drops: Anti inflammatory

20. Definitive treatment: Peripheral iridotomy LASER Iridotomy Trabeculectomy (Filtration Surgery) Fellow Eye Prophylaxis: Pilocarpine eye drops 1drop QID Prophylactic LASER Iridotomy

21. Take home message….. Glaucoma as a disease affecting optic nerve, Raised IOP as a risk factor only. Pupillary block mechanism of PACG. 4 stages of progression: PACS, AC, AAC, PACG. Optic Nerve Damage & Visual Field Defects must be present in PACG. Immediate therapy with Mannitol and Topical Antiglaucoma : B-blockers, PG Analog, Pilocarpine Definitive treatment- Iridotomy , Trabeculectomy

22. Thank You!!!!