Symptomatic Lumbar Facet Joint Synovial Cysts: Clinical Assessment of Facet Joint Steroid Injection after 1 and 6 Months and Long-term Follow-up in 30 Patients. - Parlier-Cuau,C.; Wybier,M.; Nizard,R.; Champsaur,P.; Le Hir,P.; Laredo,J.D. (Radiology, 1999)