LASER THERAPY IN GLAUCOMA Sun Xiao Dong Sun Xiao Dong

Laser Procedures Laser trabeculoplasty(LTP) Laser trabeculoplasty(LTP) Laser peripheral iridotomy(LPI) Laser peripheral iridotomy(LPI) Cyclophotocoagulation(CPC) Cyclophotocoagulation(CPC) Other uses Other uses

Laser Trabeculoplasty(LTP) Apply multiple laser burns to the trabecular meshwork to improve aqueous outflow Apply multiple laser burns to the trabecular meshwork to improve aqueous outflow Lasers Lasers Argon(ALT) Argon(ALT) Nd:YAG(SLT) Nd:YAG(SLT)

Indications for LTP Supplement to maximum tolerated medical therapy Supplement to maximum tolerated medical therapy Poor compliance Poor compliance Initial therapy(GLT) Initial therapy(GLT)

Laser Trabeculoplasty(LTP) Contraindications: 1.Corneal edema 1.Corneal edema 2.Complete angle closure glaucoma 2.Complete angle closure glaucoma 3.Age ﹤ 35 years 3.Age ﹤ 35 years 4.Some secondary open angle glaucomas(eg uveitic glaucoma,angle recession glaucoma) 4.Some secondary open angle glaucomas(eg uveitic glaucoma,angle recession glaucoma) Relative contraindication

ALT Preoperative treatment: 1 drop of lopidine 1hour before treatment 1 drop of lopidine 1hour before treatment Postoperative treatment: 1.1 drop of lopidine immediately after treatment 1.1 drop of lopidine immediately after treatment 2.Iop check 1-3 hours after treatment and first 2.Iop check 1-3 hours after treatment and first postlaser day postlaser day 3. Pres Forte 1% qid for 4 days 3. Pres Forte 1% qid for 4 days 4.Evaluate effect in 4-6 weeks 4.Evaluate effect in 4-6 weeks

ALT Laser technique: 1.Goldmann 3-mirror or 1-mirror lens 1.Goldmann 3-mirror or 1-mirror lens 2.Argon laser settings: 2.Argon laser settings: mW(average 800mW) mW(average 800mW) 50 μm 50 μm 0.1sec 0.1sec 3.50 burns over 180°or100 burns over 360°applied 3.50 burns over 180°or100 burns over 360°applied to junction of pigmented and nonpigmented TM to junction of pigmented and nonpigmented TM

ALT Complications: Complications: 1. Elevation of IOP 1. Elevation of IOP 2. Progression of visual field 2. Progression of visual field 3. Iritis 3. Iritis 4. Peripheral anterior synechiae 4. Peripheral anterior synechiae 5. Corneal epithelial and endothelial damage 5. Corneal epithelial and endothelial damage

ALT 1.Short-term results 1.Short-term results initial success: 65-95% initial success: 65-95% Reduction in IOP: 20-30% Reduction in IOP: 20-30% 2.Long-term results 2.Long-term results Attrition rate: 5-10% per year Attrition rate: 5-10% per year 5 year succes rate: 50% 5 year succes rate: 50%

ALT Factors influencing response: Factors influencing response: 1.Pre-treatment IOP 1.Pre-treatment IOP 2.Aphakia/pseudophakia 2.Aphakia/pseudophakia 3.Age 3.Age 4.Race 4.Race 5.Type of glaucoma 5.Type of glaucoma

Laser Trabeculoplasty Pathophysiology: 1. Shrinkage of collagen in TM which pulls open the intertrabecular spaces between treatment sites(Wise &Witter) 1. Shrinkage of collagen in TM which pulls open the intertrabecular spaces between treatment sites(Wise &Witter) 2. Stimulates trabecular endothelial cells to divide and migrate(Acott) 2. Stimulates trabecular endothelial cells to divide and migrate(Acott) 3. Stimulates trabecular endothelial cells to produce an altered extracellular matrix that is less outflow-obstructing(VanBuskirk) 3. Stimulates trabecular endothelial cells to produce an altered extracellular matrix that is less outflow-obstructing(VanBuskirk)

SLT Author/YearEyes Response Rate IOP Decrease Latina, %23.5% Lanzetta, % Gracner, %21.6% Melamed, %30% Cvenkel, %17.1%

ALT vs SLT Author/YearEyes IOP Decrease Damji, ALT 18 SLT 22%21% Popiela, ALT 27 SLT 13.0%13.4% Martinez-de-la- casa, ALT 20 SLT 19.5%22.2%

Laser Peripheral Iridotomy(LPI) Create a hole in the iris to relieve pupillary block Lasers Argon Argon Nd:YAG Nd:YAG

Pupillary Block

LPI Indications: Indications: 1. Acute ACG 1. Acute ACG 2. Chronic ACG 2. Chronic ACG 3. Aphakic/pseudophakic pupillary block 3. Aphakic/pseudophakic pupillary block 4. Partial thickness surgical iridectomy 4. Partial thickness surgical iridectomy 5. Before laser trabeculoplasty in eyes with narrow 5. Before laser trabeculoplasty in eyes with narrow angles angles 6. Pigment dispersion syndrome/pigmentary glaucoma 6. Pigment dispersion syndrome/pigmentary glaucoma

LPI Indications: Prophylactic laser iridotomy 1.Acute ACG in other eye 1.Acute ACG in other eye 2.Symptoms of subacute ACG 2.Symptoms of subacute ACG 3.Appositional closure 3.Appositional closure 4.PAS 4.PAS 5.↑IOP and closure of angle with dilation 5.↑IOP and closure of angle with dilation 6.Inability to be evaluated promptly 6.Inability to be evaluated promptly 7.Patient anxiety regarding risk of ACG 7.Patient anxiety regarding risk of ACG

LPI Contraindications: Contraindications: 1.Significant corneal edema 1.Significant corneal edema 2.Flat AC 2.Flat AC 3.Completely closed angle 3.Completely closed angle 4.Angle closure glaucoma not caused by pupillary block 4.Angle closure glaucoma not caused by pupillary block

LPI Preoperative treatment: 1 drop of lopidine and pilocarpine 1 hour before treatment 1 drop of lopidine and pilocarpine 1 hour before treatment Postoperative treatment: 1. 1 drop of lopidine immediately after treatment 1. 1 drop of lopidine immediately after treatment 2. IOP check 1-2 hours after treatment 2. IOP check 1-2 hours after treatment 3. Pred Forte 1% qid for 1 week 3. Pred Forte 1% qid for 1 week

LPI Laser technique: 1.Abraham or Wise lens 1.Abraham or Wise lens 2.Laser settings: 2.Laser settings: Argon: mW Argon: mW 50μm 50μm sec sec Nd:YAG: 3-7mJ Nd:YAG: 3-7mJ 1-3shots/pulse 1-3shots/pulse

LPI Laser technique: 1.Select site at 12:00 in base of a peripheral iris crypt 1.Select site at 12:00 in base of a peripheral iris crypt 2.Endpoint: 2.Endpoint: Pigment epithelium storm Pigment epithelium storm Lens capsule visualized Lens capsule visualized Clear iris transillumination Clear iris transillumination

LPI Complications: Complications: Hyphema Hyphema Iritis Iritis Increased IOP Increased IOP Corneal epithelial and endothelial burns Corneal epithelial and endothelial burns Lens opacities Lens opacities Pupillary distortion Pupillary distortion Monocular diplopia and glare Monocular diplopia and glare Closure of iridotomy Closure of iridotomy

Cyclophotocoagulation(CPC) Destroy cilary body to reduce the rate of aqueous productionLasers Diode Diode Nd:YAG Nd:YAG

CPC Indications: 1.Pain caused by high IOP in eye with little or no visual potential 1.Pain caused by high IOP in eye with little or no visual potential 2.Unable to undergo filtering surgery for medical reasons 2.Unable to undergo filtering surgery for medical reasons 3.Failed piror filtering surgery and/or at high risk of failure for repeat filtering surgery 3.Failed piror filtering surgery and/or at high risk of failure for repeat filtering surgery

CPC Preoperative treatment: Retrobulbar anesthesia Retrobulbar anesthesia Postoperative treatment: 1. Patch for 24 hrs 1. Patch for 24 hrs 2.Atropine 1% bid and Pred Forte 1% q 2 hrs WA gradually tapered over several weeks 2.Atropine 1% bid and Pred Forte 1% q 2 hrs WA gradually tapered over several weeks 3. Resume glaucoma medications except miotics 3. Resume glaucoma medications except miotics

CPC Postoperative treatment: Narcotic analgesic prn pain Narcotic analgesic prn pain Retreatment if needed about 1 month after initial procedure Retreatment if needed about 1 month after initial procedure

CPC Laser technique: Noncontact,slit lamp system or contact probe,fiberoptic system Noncontact,slit lamp system or contact probe,fiberoptic system Nd:YAG laser settings: Nd:YAG laser settings: 4-8J 4-8J burns over 360°about 1 mm posterior to limbus burns over 360°about 1 mm posterior to limbus

CPC Laser technique: Diode laser settings: Diode laser settings: 1-2W 1-2W 2.0 sec 2.0 sec 18 burns over 270°about 1 mm posterior to limbus 18 burns over 270°about 1 mm posterior to limbus

CPC Complication: Iritis Iritis Pain Pain Conjunctival burns Conjunctival burns Visual loss Visual loss Phthisis bulbi Phthisis bulbi Hypotony Hypotony Cystoid macular edema Cystoid macular edema

CPC Complications: Corneal graft rejection Corneal graft rejection Hyphema Hyphema Vitreous hemorrhage Vitreous hemorrhage Cataract Cataract Suprachoroidal hemorrhage Suprachoroidal hemorrhage Serous choroidal effusion Serous choroidal effusion Sympathetic ophthalmia Sympathetic ophthalmia

Other uses of Laser Therapy Laser suture lysis 1.Use laser to cut sutures in the trabeculectomy flap to improve filtration in the early postoperative period 1.Use laser to cut sutures in the trabeculectomy flap to improve filtration in the early postoperative period 2.Laser technique 2.Laser technique Hoskins or Ritch lens Hoskins or Ritch lens Argon laser settings: mW Argon laser settings: mW 50 μm 50 μm sec sec

Other uses of Laser Therapy Laser peripheral iridoplasty 1.Use laser to create contradiction burns in the peripheral iris to open an appositionally closed angle (eg plateau iris syndrome,nanophthalmos) 1.Use laser to create contradiction burns in the peripheral iris to open an appositionally closed angle (eg plateau iris syndrome,nanophthalmos) 2.Laser technique: 2.Laser technique: Abraham or Goldmann lens Abraham or Goldmann lens Argon laser settings: mW Argon laser settings: mW 500 μm 500 μm sec sec