Zonal anatomy of the cervix: correlation of MR imaging and histologic examination of hysterectomy specimens.

High-resolution magnetic resonance (MR) images of nine hysterectomy specimens were correlated with light microscopy, computer-aided image analysis, and immunohistochemical examination to investigate the histologic counterparts of the zonal anatomy of the cervix. A central stripe of high signal intensity, a surrounding middle layer of low signal intensity, and an outer layer of intermediate signal intensity were found in all specimens. Histologic correlation indicated that the central stripe most likely represents the secretions in the canal, the cervical mucosa, and the plicae palmatae; the other two layers represent fibromuscular stroma. The percentage of nuclear area in the inner zone of the fibromuscular stroma is 2.5 times greater than in the outer zone, which may account for the lower signal intensity of the inner zone. No difference in distribution of collagen, laminin, and fibronectin (common components of the extracellular matrix) was found between the two zones of the cervical fibromuscular stroma.