Continuous wave cyclophotocoagulation (CWCPC) delivers continuous high intensity energy to the ciliary body in an attempt to reduce aqueous secretion and hence lower IOP. It is often used as a treatment of last resort due to the potential side-effects of hypotony, visual deterioration and phthisis bulbi. Micro pulse cyclophotocoagulation (MPCPC) administers a series of repetitive, short pulses of laser energy separated by rest periods. A preliminary study has described MPCPC to achieve IOP reduction that is sustained over 12-18 months without significant ocular comorbidity. This randomised comparative exploratory study compared the efficacy and safety of MPCPC and CWCPC in refractory glaucoma. Forty-eight patients with refractory glaucoma (IOP>21 unresponsive to maximal tolerated medical therapy with or without previous surgical intervention) and a best corrected visual acuity (BCVA) of 6/60 or worse were randomised to either CWCPC or MPCPC. Twenty-four patients were allocated to each group. The primary outcome of success was IOP between six and 21mmHg and at least 30% reduction in IOP with or without medical therapy. After 12 months, 75% of patients in the MPCPC vs. 29% in the CWCPC achieved the primary outcome. However, there was no significant difference between the two treatment modalities achieving primary outcome success at 18 months. More complications were seen in the CWCPC group, including prolonged anterior chamber (AC) inflammation and phthisis bulbi. The authors conclude that MPCPC provides a more consistent and predictable effect in lowering IOP with minimal complications.