Table 1.
Additive scoring system for assessing inflammation and damage of temporomandibular joint by magnetic resonance imaging
| Item | Definition | Grade 0 | Grade 1 | Grade 2 |
|---|---|---|---|---|
| A) Inflammatory domain (possible total scores 0–8) | ||||
| Bone marrow oedema | Compared to the mandibular ramus, hyperintense marrow signalling within the condyle on fluid-sensitive images, and/or hypointense signalling on precontrast T1-weighted images without fat saturation. | Absent | Present | |
| Bone marrow enhancement | Compared to the mandibular ramus, hyperintense marrow signalling within the condyle on postcontrast T1-weighted fat-saturated images. | Absent | Present | |
| Joint effusion | Increased joint fluid with isointense signalling of joint space compared to that of cerebrospinal fluid on fluid-sensitive images. | Absent ≤1 mm fluid in joint recess. |
Small >“>1 and ≤2 mm thickness in recess or involving entire joint compartment. |
Large >2 mm thickness in recess or involving entire joint compartment. |
| Synovial thickening | Thickened synovial lining of the joint compartments with intermediate signal intensity on fluid-sensitive images. | Absent No synovium visible (apparent joint compartment ≤1 mm width). |
Mild >1 and ≤2 mm thickness at the point of maximum synovial thickening. |
Moderate/severe >2 mm thickness at the point of maximum synovial thickening. |
| Joint enhancement | Signal intensity of the synovium, capsule and joint fluid higher than that of muscle on postcontrast T1-weighted fat-saturated images. | Normal High signal intensity confined to signal perimeter of normal amount of fluid on corresponding fluid-sensitive image. |
Mild High signal intensity focally exceeding signal perimeter of physiological amount of joint fluid on corresponding fluid-sensitive image. |
Moderate/severe High signal intensity diffusely involving one or both joint compartments. |
| B) Damage domain (possible total scores 0–5) | ||||
| Condylar flattening | Loss of the round or slightly angular shape of the condylar head, viewed in the sagittal-oblique plane. | Absent Round/slightly angular shape of condyle. |
Mild Extent of flattening involves part of the surface of the condyle. |
Moderate/severe Extent of flattening involves the entire surface of the condyle, or loss of height of the condyle. |
| Erosions | Any irregularity or break of the bony joint surfaces leading to the loss of the smooth continuous outline of the bone. | Absent No irregularities or deep breaks. |
Mild Presence of irregularities involving only part of the articular surface of the condyle. |
Moderate/severe Presence of deep breaks in the subchondral bone seen in two planes, or irregularities involving the entire articular surface of the condyle. |
| Disk abnormalities | Any abnormality of the articular disk, including flattening, displacement or destruction. | Absent | Present | |