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MCPC / GCPC / ECP

Your Aqueous reduction procedure - lowering pressure by reducing fluid production

Reduction procedures target the ciliary processes to lower aqueous production to lower IOP. ECP (Endocyclophotocoagulation) is done from inside the eye and adds precision to the procedure with direct visualization of the ciliary processes through an endoscopic camera and is usually performed during cataract surgery MCPC (micropulse laser) is the first-line standalone option for Aqueous reduction procedures; GCPC (G-probe) for more refractory cases.

R6 - Reduction. Reduction procedures lower eye pressure by reducing how much fluid your eye makes. ECP does this using direct visualization. MCPC and GCPC use a transscleral diode laser - MCPC first for most patients, with GCPC reserved for those who need more aggressive reduction or have painful, very high-pressure eyes.

Understanding the three Reduction procedures

All three target the ciliary processes - the ring of tissue just behind the iris that produces the aqueous fluid your eye makes every day. By reducing its output, we lower the amount of fluid entering the eye and therefore the eye pressure. The difference is in how each procedure reaches and treats it.

ECP

Endoscopic cyclophotocoagulation - can be combined with other procedures

ECP uses a tiny camera on the laser probe to directly visualize the ciliary processes and apply targeted laser treatment. It is most commonly combined with cataract surgery or another glaucoma procedure - but can also be performed as a standalone procedure when reducing aqueous production is the primary goal. EPSAZ offers the LEOS - ECP system, the only such system currently available in Arizona.

MCPC

Micropulse cyclophotocoagulation - first-line standalone reduction

MCPC delivers diode laser energy through the sclera in rapid pulses with rest periods between each pulse. The micropulse pattern reduces heat buildup, making MCPC safer and less painful than traditional continuous-wave laser. It is used for patients who need additional pressure reduction as a standalone procedure. Less inflammation and faster recovery.

GCPC

Continuous-wave cyclophotocoagulation - refractory cases

GCPC delivers diode laser energy continuously, producing a stronger effect than MCPC. It is used when MCPC has not achieved sufficient reduction or is not an option such as, when pressure is very high, or when the eye is painful and needs urgent relief. GCPC can cause more inflammation than MCPC - pain medication (T3) is prescribed after the procedure to be used if needed. .

Why Reduction is the final step in the R's framework

The R's framework begins with approaches most in harmony with your eye's natural design and progresses toward more interventional steps. Reduction is the final step because it alters the fundamental production side of the fluid cycle - rather than improving drainage, it reduces how much fluid is made. This changes your eye's normal fluid dynamics in a less invasive way than outflow procedures which require incisional surgery?

Important note on anatomy and power. The ciliary body produces aqueous humor at the base of the ciliary processes. MCPC and GCPC directs laser energy through the sclera (the white outer coat of the eye) from outside - this energy reaches all the way to the internal wall of the eye where production occurs, resulting in effective suppression of fluid production. ECP uses a camera probe that sees and treats the tips of the ciliary processes from inside the eye - precise and targeted, but it reaches only the tips rather than the base, making it somewhat less powerful for aqueous suppression but less likely to cause post op inflammation. This is why ECP is most often used as an adjunct to add incremental IOP lowering, while MCPC/GCPC are the primary standalone reduction options.

ECP is a precise, targeted option - most often used to add IOP lowering at the time of cataract or other glaucoma surgery. It can also be performed standalone when the goal is to reduce aqueous production as a primary treatment.

EPSAZ outcomes - 1,114 diode (MCPC/GCPC) laser patients - through 60 months

1,114Diode laser procedures at EPSAZ
-8.8 mmHgAverage IOP reduction at 12 months
21.6%Average percentage IOP reduction

Outcomes by severity

Outcomes by severity
SeverityPatientsPre IOPPost IOPIOP dropMeds saved
Mild3621.414.5-6.9 (20.4%)-0.48
Moderate5219.814.8-5.0 (21.7%)-0.21
Severe27021.014.3-6.7 (22.7%)-0.33

IOP reduction is consistent across all severity levels. Medication change is modest - this procedure is primarily about pressure control, not medication elimination. Approximately 1 in 3 patients requires a repeat treatment at 3 months.

What to expect - MCPC

  1. Before - Transillumination marking: A light probe is used to allow marking and localization of the ciliary body on the scleral surface. This ensures accurate targeting of the laser energy.
  2. During - 10-15 minutes in the laser room: The laser probe is applied to the scleral surface. Treatment is given over multiple spots in each quadrant. MCPC: micropulse delivery - local block anesthesia is given and minimal discomfort is usual GCPC: continuous wave - local block will provide comfort although topical steroid drops are always required
  3. After - Simpler recovery than filtration surgery without incisional surgery: MCPC: mild to moderate discomfort for 1-3 days. Steroid drops are prescribed. Vision typically stabilizes in 2-4 weeks. GCPC: typically more inflammation and discomfort.

Repeat treatment is common. About 1 in 3 MCPC patients has a repeat procedure at 3 months if the initial response is insufficient. About 1 in 5 GCPC patients require a repeat procedure at 3 months. This is expected and built into your follow-up schedule. Repeat MCPC/GCPC can be performed safely.

Side effects

~33%Repeat treatment needed for MCPC - Not a failure - repeat at 3 months is expected and planned for.
CommonInflammation and discomfort - Managed with steroid drops. More significant with GCPC - pain medication prescribed.
~5%Cystoid macular edema - Fluid in the macula causing temporary vision reduction. Managed with additional drops.
RareHypotony - MCPC - Pressure too low - rare with MCPC, more common with GCPC. Monitored closely.
Extremely RareSympathetic ophthalmia - Extremely rare inflammatory response involving the other eye. Prompt evaluation required if other eye becomes inflamed.

Your follow-up schedule

Week 2OD - Pressure, inflammation check
Week 8-10MD - healing and IOP response
RepeatAt 3 months if needed
FollowupAs scheduled

Resources

Questions about your procedure, your follow-up visits, or your drops? We are here.

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