Explanation – Pseudoexfoliative glaucoma

Q. What should be done for the fellow eye in clinically unilateral PXFG?

A) No treatment is necessary

B) Regularly check for IOP elevation

C) Immediate cataract surgery

D) Immediate laser trabeculoplasty

Answer: B) Regularly check for IOP elevation and glaucoma

Explanation: In clinically unilateral PXFG, the fellow eye also needs to be regularly checked for IOP elevation and signs of glaucoma, as the conversion rate to PXFG is high. Early detection and management can help prevent vision loss in the second eye.

Monitoring and Management

• Unilateral PXFG:
  • Fellow Eye Monitoring: Regularly check the fellow eye for IOP elevation and signs of glaucoma, as there is a high conversion rate to PXFG. Early detection and intervention can help manage the condition effectively.
• Aggressive Monitoring:
  • Higher Risk of Progression: PXFG progresses more rapidly than POAG, necessitating more aggressive monitoring and treatment adjustments to maintain control over IOP and prevent optic nerve damage.
• Medical Management:
  • IOP-Lowering Medications: Use of topical medications such as beta-blockers, prostaglandin analogs, alpha agonists, and carbonic anhydrase inhibitors.
  • Combination Therapy: Often necessary due to the aggressive nature of PXFG.
• Surgical Management:
  • Laser Trabeculoplasty: Can be considered to enhance aqueous outflow.
  • Filtering Surgery: Trabeculectomy or glaucoma drainage devices for advanced or refractory cases.
• Cataract Surgery:
  • Preoperative Assessment: Thorough assessment of zonular integrity and planning for potential complications.
  • Postoperative Monitoring: Regular follow-up to monitor for late complications such as IOL dislocation.
  • Complications associated with cataract surgery in PXF can occur from poor pupillary dilation, zonular weakness leading to intraoperative or postoperative lens dislocation and vitreous loss, postoperative intraocular pressure (IOP) spikes potentiating glaucomatous damage, capsular phimosis, prolonged inflammation, and postoperative corneal decompensation.

👁️ PXF and PXFG: Monitoring, Treatment & Management

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🔎 1. MONITORING

🔬 In Pseudoexfoliation Syndrome (PXF) (without glaucoma):

Patients with PXF are at risk of developing ocular hypertension (OHT) or PXFG and require lifelong surveillance.

🛠️ Monitoring Strategy:

Parameter	Frequency	Notes
IOP	Every 6–12 months	Diurnal variation may miss spikes; consider phasing
Gonioscopy	Annually	To assess angle pigmentation and Sampaolesi’s line
Optic Nerve Head (ONH)	Annually	Disc photos to track cupping progression
OCT of RNFL and Macula	Baseline, then as indicated	RNFL thinning may precede visual field loss
Visual Fields (24-2 or 10-2)	Annually or sooner if OHT present	Look for early arcuate or nasal step defects

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🔬 In Pseudoexfoliative Glaucoma (PXFG):

PXFG is progressive and more aggressive than primary open-angle glaucoma (POAG), requiring closer monitoring.

🛠️ Monitoring Strategy:

Parameter	Frequency	Notes
IOP (Goldmann Tonometry)	Every 3–6 months	Watch for fluctuations and peaks
ONH and RNFL	Every 6–12 months	Evaluate rim thinning, cupping
OCT	Every 6–12 months	RNFL thinning often precedes field loss
Visual Fields	Every 6 months initially	More frequent if progression noted
Gonioscopy	Annually or with suspicion of angle narrowing	Sampaolesi’s line, pigment overload
Cataract status	Monitor zonular health	Phacodonesis, lens instability

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💊 2. MEDICAL TREATMENT

The goal is to lower IOP, reduce optic nerve damage, and preserve vision.

💧 First-Line Agents: Prostaglandin Analogues

Drug	Dose	Mechanism	Contraindications
Latanoprost	0.005% OD at night	↑ Uveoscleral outflow	History of herpetic keratitis
Travoprost	0.004% OD	↑ Uveoscleral outflow	Caution in uveitic eyes
Tafluprost	Preservative-free option	Good in dry eyes	As above

• Highly effective (~30% IOP reduction)
• Once-daily dosing aids compliance

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💧 Second-Line: Beta-Blockers

Drug	Dose	Mechanism	Contraindications
Timolol	0.25–0.5% BID	↓ Aqueous production	Asthma, bradycardia, heart block
Betaxolol	Selective β1-blocker	Safer in lung disease	Less effective IOP control

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💧 Third-Line: Carbonic Anhydrase Inhibitors (Topical)

Drug	Dose	Mechanism	Contraindications
Dorzolamide	2% BID–TID	↓ Aqueous production	Sulfa allergy
Brinzolamide	1% BID	Better comfort profile	Same as above

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💧 Fourth-Line: Alpha-2 Agonists

Drug	Dose	Mechanism	Contraindications
Brimonidine	0.1–0.2% BID–TID	↓ Aqueous + ↑ Uveoscleral outflow	Young children, depression, MAOIs

• May have neuroprotective potential

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💊 Systemic Therapy (for short-term IOP spikes)

Drug	Mechanism	Notes
Acetazolamide	Oral carbonic anhydrase inhibitor	250–500 mg BID–QID; caution in renal disease
Glycerol / Mannitol	Hyperosmotics	Used in acute IOP spikes or pre-op

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🩺 3. LASER TREATMENT

🔦 Selective Laser Trabeculoplasty (SLT)

• Effective in PXFG due to heavily pigmented TM
• May be used early as first-line or adjunct
• Can be repeated
• IOP lowering: ~20–25%
• Safer than ALT (argon laser trabeculoplasty)

Limitations:

• Less durable in PXFG (often lasts 1–2 years)
• Less effective in very high baseline IOP (>35 mmHg)

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🔪 4. SURGICAL MANAGEMENT

Often required earlier in PXFG due to:

• Poor medication response
• High and fluctuating IOP
• Rapid progression

✂️ Trabeculectomy

• Gold standard for IOP reduction
• Often requires antifibrotic agents (e.g., mitomycin-C) to reduce scarring
• Risks:
  • Hypotony
  • Bleb leaks/infection
  • Increased post-op inflammation in PXFG

✂️ Glaucoma Drainage Devices (Tubes)

• Preferred in eyes with prior surgery, uveitis, or high risk of scarring
• Options: Ahmed valve, Baerveldt implant

✂️ Minimally Invasive Glaucoma Surgery (MIGS)

• iStent, Hydrus, XEN gel stent
• Good for mild-to-moderate PXFG, often combined with cataract surgery
• Limited long-term data in PXFG compared to POAG

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👁️ 5. CATARACT SURGERY IN PXFG

PXF patients are at high risk of intraoperative complications:

Risk	Precautions
Zonular weakness	Use capsular tension ring (CTR)
Poor dilation	Use iris hooks or Malyugin ring
Post-op IOP spike	Consider prophylactic IOP-lowering meds

Combined phaco + MIGS may be ideal in appropriate patients.

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🧠 Key Points Summary

Category	Notes
Monitoring	Regular IOP, ONH, VF, OCT monitoring; lifelong surveillance
First-line treatment	PG analogues; add other drops if target IOP not reached
Laser	SLT effective; may delay surgery
Surgery	Trabeculectomy or tube often needed earlier than in POAG
Cataract	High complication risk; CTR and pupil devices may be needed
Compliance	Challenging in elderly; once-daily drops preferred