Table 1.
Imaging-based classifications of adenomyosis proposed so far.
| Author(s) and Year of Publication | Imaging Platform | Proposed Classification | Rationale | Remarks |
|---|---|---|---|---|
| Kishi et al. (2012) [19] | MRI | Four subtypes: I: intrinsic; II: extrinsic; III: intramural; IV: indeterminate |
Based on Sampson’s observation as well as clinical observations | Subtypes I and II appear to have different pathogenesis, symptomology, and severity |
| Van den Bosch et al. (2015) [36] Revised in Harmsen et al. (2022) [21] (The MUSA standard) |
TVUS | Direct features: Cysts, hyperechogenic islands, echogenic subendometrial lines and buds. Indirect features: Asymmetrical thickening, globular uterus, irregular JZ, fan-shaped shadowing, translesional vascularity, interrupted JZ. |
Based on expert consensus through several rounds of modified Delphi procedure | A welcome step towards the establishment of standardized terminology, with the goal to build a uniformly accepted or validated system to diagnose or classify the severity of adenomyosis based on imaging findings. |
| Bazot and Darai (2018) [14] | MRI | Three subtypes: -Internal -External -Adenomyoma |
Based on Sampson’s observation as well as clinical observations | Different subtypes appear to have different pathogenesis, symptomatology, and severity |
| Gordts et al. (2018) [5] | MRI/TVUS/hysteroscopy | Important parameters to be included in a classification system: Affected area (inner or outer myometrium), localization (anterior, posterior, or fundus), pattern (diffuse or focal), type (muscular or cystic), volume or size (expressed as <1/3, <2/3, >2/3 or in cm) | These parameters are potentially related to symptomatology and/or severity | Included parameters are important for accurate diagnosis and, through grading, may be associated with disease severity. |
| Van den Bosch et al. (2019) [37] | TVUS | Location (anterior, posterior, left or right lateral side, or fundus), differentiation (focal, diffuse, or mixed type), cysticity (cystic or non-cystic), uterine layer involvement ( I: involving inner/sub-endometrial myometrium; II: involvement of middle myometrium; III: involvement of outer/sub-serosal myometrium), extent (<1/4, ≥1/4 but ≤1/2, >1/2 myometrium), and size. |
Based on consensus among sonographers, and consistent with the previous MUSA consensus. | A welcome first step towards an internationally accepted classification and reporting system |
| Kobayashi and Matsubara (2020) [20] | MRI | Five main categories: (1) affected area (internal vs. external), (2) pattern (diffuse, focal); (3) size (<1/3, <2/3, or >2/3 of uterine wall); and (4) localization (anterior, posterior, left lateral, right lateral, and fundus); (5) concomitant pathologies (none, PE, OE, DE, UF, others) | Adopted from previous proposals of classification | Combined all important features of adenomyosis that may be useful for proper classification |
| Exacoustos et al. (2020) [25] | TVUS | Type (focal, diffuse, or adenomyomas), Extension of the lesion in the myometrium |
Empirical observations | These variables seem to correlate with the severity of symptoms and infertility |
Abbreviations used in the table: DE: deep endometriosis; JZ: junctional zone; MRI: magnetic resonance imaging; OE: ovarian endometrioma; PE: peritoneal endometriosis; UF: uterine fibroids.