Table 1
The ultrasound characteristics of the masses.
| PATIENT NUMBER | SEX | AGE (MONTHS) | SIDE | LATERO-LATERAL LENGTH (MM) | ANTERO-POSTERIOR LENGTH (MM) | CEPHALO-CAUDAL LENGTH (MM) | ULTRASOUND FINDINGS |
|---|---|---|---|---|---|---|---|
| 1 | M | 1.9 | Right | 12 | 7 | 25 | Heterogenous sternocleidomastoid mass, diagnosed as fibromatosis colli. No adenomegaly. |
| 2 | M | 2.17 | Left | 16 | 18 | 34 | Heterogenous sternocleidomastoid mass, diagnosed as fibromatosis colli. No adenomegaly. |
| 3 | F | 1.67 | Left | 12 | 12 | 23 | Heterogenous mass seemingly adjacent to the sternocleidomastoid muscle, fibromatosis colli suggested as the most likely diagnosis. No adenomegaly. |
| 4 | F | 1.23 | Left | 17 | 14 | 31 | Heterogenous sternocleidomastoid mass, diagnosed as fibromatosis colli. No adenomegaly. |
| 5 | M | 1.07 | Left | 17 | 33 | 32 | Cervical mass is suspicious for neuroblastoma diagnosed in an external institution. |
| 6 | M | 8.33 | Right | 11 | 11 | 21 | No ultrasound before the MRI. Heterogenous sternocleidomastoid mass without adenomegaly at follow-ultrasound. |
Table 2
The MRI characteristics using different weightings of the fibromatosis colli in each patient.
| PATIENT | AGE (MONTHS) | CONTRAST ENHANCEMENT | DIFFUSION WEIGHTED IMAGING | T1 SIGNAL | T2 SIGNAL | FLUID SENSITIVE FAT-SATURATION SEQUENCE |
|---|---|---|---|---|---|---|
| 1 | 1.9 | Thick peripheral enhancement | Not performed | Isointense to muscle | Slightly hyperintense to muscle | STIR: Heterogenous hyperintensity compared to adjacent muscle |
| 2 | 2.17 | Thick peripheral enhancement | Not performed | Isointense to muscle | Heterogeneously hyperintense to muscle | T2 DIXON Fat-Sat: Heterogenous hyperintensity compared to adjacent muscle |
| 3 | 1.67 | Thick peripheral enhancement | Slightly hyperintense (ADC 1.25–1.4) | Isointense to muscle | Heterogeneously hyperintense to muscle | T2 DIXON fat-sat: Heterogenous hyperintensity compared to adjacent muscle |
| 4 | 1.23 | Thick peripheral enhancement | Slightly hyperintense (ADC 1.25–1.4) | Isointense to muscle | Heterogeneously hyperintense to muscle | T2 DIXON fat-sat: Heterogenous hyperintensity compared to adjacent muscle |
| 5 | 1.07 | Thick peripheral enhancement | No signal (artefact) | Isointense to muscle | Heterogeneously hyperintense to muscle | T2 DIXON fat-sat: Heterogenous hyperintensity compared to adjacent muscle with slight peripheral soft tissue oedema |
| 6 | 8.33 | Not performed | Not within field of view | Isointense to muscle | Isointense to muscle | Not performed |
Figure 1
T1-weighted axial images from patients 1 to 5 (parts a–e) of the fibromatosis colli (arrows), isointense to the adjacent muscle. Part (d) is a T1-weighted coronal image of the fibromatosis colli (arrow) in patient 6.
Figure 2
Contrast enhanced T1-weighted imaging, demonstrating the thick enhancing rim of the fibromatosis colli around a centre that remains isointense to the adjacent muscle (arrows). The coronal images (a) to (e) represent patients 1 to 5, with (f) being an axial reformatting of patient 5.
Figure 3
T2-weighted axial images from patients 1, 2 and 4 (labelled a–c) showing heterogeneous T2 hyperintensity of the fibromatosis colli (arrows).
Figure 4
Diffusion weighted imaging (DWI b800) performed in patients 3 and 4 (parts a and b, respectively) showing hyperintensity of the fibromatosis colli (arrows) with accompanying low ADC values ranging from 1.25 to 1.4.