- endometrial tissue in myometrium
- secondary smooth muscle hypertrophy and hyperplasia
- diffuse or focal
clinical presentation
- dysmenorrhea
- dysfunctional uterine bleeding
ultrasound
- enlarged, globular uterus
- myometrial heterogeneity
- echogenic myometrial nodules
- subendometrial echogenic linear striations
- 2-6 mm subendometrial cysts
- endometrial pseudowidening: poor definition of endomyometrial junction
- rain shower appearance: multiple fine areas of attenuation throughout the lesion
- doppler: speckled pattern of increased vascularity within heterogeneous area
MRI
- areas of low myometrial signals in T2
- focal or diffuse thickening of junctional zone
| Junctional zone | |
| > 12 mm | high accuracy of diagnosis |
| 8-12 mm | needs other criteria a: high signal intensity striations extending out from endometrium into myometrium b: high signal intensity in T1 representing endometrial rests or punctate hemorrhages |
| < 8 mm | excludes disease with high accuracy |