AUG 26, 2021
Two multicenter, prospective randomized clinical trials evaluated pneumatic vitreolysis (PVL) in eyes with vitreomacular traction (VMT) with and without full-thickness macular hole (FTMH).
Researchers recruited patients with central VMT with vitreomacular adhesion of 3000 μm or less. Protocol AG compared PVL versus sham injection for VMT without FTMH in 46 participants. The main outcome measure was VMT release at 24 weeks without rescue treatment. Protocol AH assessed the efficacy of PVL for closure of FTMH (250 μm or less at the narrowest point) in 35 patients. The main outcome measure was FTMH closure at 8 weeks without rescue treatment.
In protocol AG, more eyes in the PVL group had central VMT release without rescue vitrectomy than in the sham group by 24 weeks (78% vs. 9%). In protocol AH, 29% of eyes had FTMH closure without rescue vitrectomy at 8 weeks. Both groups had higher than expected rates of retinal detachment and tear, resulting in early termination.
Because the studies were terminated early, planned sample size cutoffs were not met and long-term follow-up was limited. Potential variability in injection procedures and unfamiliarity with this technique may have contributed to higher rates of retinal detachment and tear than seen in previous PVL studies.
Based on these findings, the authors conclude that PVL is effective for inducing VMT release but less effective for closing FTMH. However, higher than expected rates of retinal detachments and tears (12%) led the DRCR Retina Network to discontinue both studies early.