Laser-Induced Ocular Hypertension (OHT) Model

Model Description

Glaucoma, the second leading cause of global blindness, is strongly associated with elevated intraocular pressure (IOP). Our laser photocoagulation model selectively targets the trabecular meshwork to induce sustained IOP elevation, offering:

• Controlled IOP spikes: 25-35 mmHg sustained for 3+ weeks
• Retinal ganglion cell (RGC) loss: ≥40% reduction vs controls
• Minimal complications: Reduced inflammation vs episcleral vein ligation/hypertonic saline methods

 Technical Superiority:
✓ High reproducibility: 90% success rate with standardized laser parameters
✓ Disease progression tracking: From acute IOP elevation to chronic RGC degeneration
✓ Ethical compliance: AAALAC-approved humane endpoints (IOP >40 mmHg for >72h)

Applications

• Anti-glaucoma drug testing (prostaglandin analogs, Rho kinase inhibitors)
• Neuroprotection mechanism studies (BDNF, caspase-3 pathways)
• IOP-lowering device validation (MIGS implants)
• Retinal ischemia-reperfusion injury research

Modeling Protocol —— Diode Laser Trabecular Meshwork Photocoagulation

1. Pre-op Preparation:

• Anesthetize rats (ketamine 75 mg/kg + xylazine 10 mg/kg)
• Apply topical tropicamide to dilate pupils

2. Laser Procedure:

• Laser Parameters: 532nm wavelength, 0.8W power, 0.5s duration
• Target Area: 360° trabecular meshwork with 60-80 spots
• Post-op topical steroid/antibiotic ointment

3. Monitoring Phase:

• Weekly IOP measurement (TonoLab® rebound tonometer)
• 3-week endpoint: ERG/RGC analysis

Validation & Testing

Technical Advantages