Three-dimensional visualization and dosimetry of stranded source migration following prostate seed implant

Stranded seeds show unexpected spatial instability in the craniocaudal dimension. Strand displacement may occur in approximately 1.5% of stranded sources placed and about 25% of cases. One may expect mean decreases in D90 and V100 of about 7% and 3%, respectively, among cases exhibiting strand migration in the first month following seed implant. Resolution of prostate edema during the same time period accounts for an approximately 30% increase in D90 and V100.