Hirudo (Leech) for proliferative vitreous retinopathy: A protocol for systemic review and meta-analysis
Huang H, Lei R, Li Y, Huang Q, Gao N, Zou W (2021) · Medicine (Baltimore) · n=0
Study Profile
- Design
- pre-registered systematic review and meta-analysis protocol for Hirudo (leech) or Hirudo-containing Chinese compound prescriptions in proliferative vitreous retinopathy (Chengdu University of Traditional Chinese Medicine, China)
- Sample size (n)
- —
- Intervention
- Planned synthesis of randomized controlled trials in English or Chinese on Hirudo (leech) and Hirudo-containing compound prescriptions for proliferative vitreous retinopathy (PVR)
- Comparator
- Cross-trial: conventional ophthalmologic care without Hirudo product
- Primary endpoint
- Change in vitreous opacity, vision changes, anterior macular membrane formation, retinal detachment recurrence, and adverse-event incidence
- Primary result
- Pre-registered protocol only - no results yet available; protocol registered at OSF (10.17605/OSF.IO/FP7VG); planned 8-database search including Cochrane, PubMed, MEDLINE, EMBASE, CNKI, CBM, VIP, and Wanfang
- Follow-up duration
- to be determined per included studies
- PMID
- 33546086
Key Findings
- First pre-registered systematic review protocol for Hirudo/leech-containing therapeutics in proliferative vitreous retinopathy
- Plans to incorporate Chinese-language databases (CNKI, CBM, VIP, Wanfang) often missing from Western reviews
- Includes both whole-leech therapy and Hirudo-containing Chinese herbal compound prescriptions in scope
- Documents the emerging investigation of leech-derived therapeutics in ophthalmologic indications outside the FDA K040187 clearance
- Pre-registration at OSF supports methodological transparency
Limitations
- Protocol only - no results available at time of registry inclusion
- Scope conflates whole-leech therapy with multi-ingredient Chinese herbal compound prescriptions - mechanistic specificity reduced
- Chinese-language source heterogeneity may produce quality challenges
- PVR is a niche ophthalmologic indication - generalizability to broader leech-therapy literature limited
- Investigators are from a single Chinese TCM institution - external validation pending
Clinical Implications
Huang 2021 is a pre-registered systematic review protocol on Hirudo (leech) therapeutics for proliferative vitreous retinopathy. The trial is included in this registry to document the emerging Chinese investigation of leech-derived ophthalmologic indications - a use case largely absent from the Western FDA-cleared K040187 framework. The protocol's ultimate publication will be informative for understanding the global leech-therapy evidence base. ASH editorial team should track the eventual full-publication output of this systematic review.
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