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Updated: Aug 14, 2026
Laparoscopic Choledochal Cyst Excision and Roux-en-Y Choledochojejunostomy in Adults
Published on: February 28, 2025
Anatomical Variants of the Cystic Duct: A 25-Year Systematic Review and Pooled Analysis of Prevalence and Surgical
R F Dias1, W Giang2, S Gangakhedkar1
1Surgical Services, John Hunter Hospital, Newcastle, New South Wales, Australia.
Background:
Anatomical variants of the cystic duct impair attainment of the critical view of safety during laparoscopic cholecystectomy, predisposing to bile duct injury, bile leak, and conversion to open surgery. No prior synthesis has examined their prevalence across all detection modalities.
Objectives:
To determine the pooled prevalence of cystic duct anatomical variants and their association with surgical outcomes.
Data Sources:
MEDLINE/PubMed, Embase, and Cochrane CENTRAL were searched from January 2000 to November 2025. Reference lists were hand-searched for additional eligible studies.
Review Methods:
PRISMA 2020-compliant systematic review and meta-analysis. Pooled prevalence estimates were calculated using a random-effects model with Freeman-Tukey double arcsine transformation. Heterogeneity was assessed using the I2 statistic and Cochran's Q test. Quality was assessed using the JBI Prevalence checklist. Prospectively registered: PROSPERO (CRD420251178103).
Results:
Fifty-three studies (n = 18 875 patients; 22 countries) were included. The pooled prevalence of any cystic duct variant was 19.1% (95% CI 13.2%-25.7%). Variant-specific estimates were: high insertion 16.6% (9.2%-25.6%; k = 16), medial insertion 7.3% (4.0%-11.5%; k = 19), low insertion 6.5% (4.2%-9.2%; k = 29), spiral/posterior course 14.6% (8.2%-22.5%; k = 17), and right hepatic duct insertion 1.3% (0.7%-2.1%; k = 15). Heterogeneity was considerable (I2 = 79.6%-99.4%), attributable to variation in detection modality and classification systems. Only 11 studies (20.8%) reported surgical outcomes; pooled conversion to open surgery rate was 11.0% (95% CI 6.9%-15.2%). No significant publication bias was detected (Egger's test p = 0.208).
Conclusion:
Cystic duct anatomical variants affect approximately one in five patients undergoing biliary imaging or cholecystectomy. The lack of a universal system and the paucity of outcome data stratified by variant subtype represent a major gap. Prospective studies using standardised nomenclature and systematically reporting surgical outcomes are urgently needed.
