NICE did a rapid review of the published literature on the efficacy and safety of this procedure. This comprised a comprehensive literature search and detailed review of the evidence from 9 sources, which was discussed by the committee. The evidence included 1 meta-analysis, 1 non-randomised comparative study and 7 case series (2 of which were also included in the meta-analysis). It is presented in table 2 of the overview. Other relevant literature is in the appendix of the overview.
The specialist advisers and the committee considered the key efficacy outcomes to be: quality of life, reduction in intraocular pressure, reduced use of medication and preservation of visual fields, in the long term.
The specialist advisers and the committee considered the key safety outcomes to be: hypotony, pain and macular oedema.
The committee noted that the technology is evolving.
The committee noted that in the context of such a common condition, there was a lack of controlled studies of sufficient statistical power, and this underpinned their recommendation for further research.