Teaching Case

22-year-old patient who complains of chronic lower back pain (at least for 1 year), which currently spreads to the right lower limb. Due to a progressive worsening of this pain, imaging tests were required.

- CT Findings

Vertically-oriented striations which represent reinforced trabeculae amidst fatty stromal tissue. This typical feature is called the "polka-dot pattern" (multiple dots) on axial CT and "the corduroy sign" on sagittal projections. (Fig.1, 2)

- MR Findings

Low-signal-intensity on T1-weighted images and high-signal-intensity on T2-weighted images, which could be related to a vascular lesion. (Fig. 3a)
Note the presence of low-signal-intensity vertical striations (low signal on all sequences), also seen on CT images. They could represent reinforced trabeculae. (Fig. 3b)
After contrast administration, the lesion enhances strongly (compatible with a vascular lesion). (Fig. 3b, c).

- CT-guided biopsy: Due to a clinical worsening, core-needle biopsy was performed, confirming the presence of a vascular lesion (Fig. 4).

- Angiography: Embolisation before decompressive surgery was also required (Fig. 5).

- Background [1, 2]

Osseous haemangiomas are frequent and the most common sites of involvement are the vertebrae (thoracic and lumbar spine) and skull.
Vertebral haemangiomas are composed of blood vessels surrounded by endothelial cells infiltrating the medullary cavity. They are usually confined to the vertebral body, although they may extend into the posterior elements (atypical behaviour).

- Clinical perspective [1, 2]

Most vertebral haemangiomas are asymptomatic. Occasionally, the may compress the spinal cord, nerve roots (young adults), show soft-tissue extension or a pathological fracture (aggressive haemangiomas).
Highly vascular haemangiomas may cause significant neurologic deficit despite an absence of spinal cord compression (probably related to blood flow disturbances in the spinal cord).

- Imaging perspective [2, 3, 4]

X-ray findings: Lytic lesions which may show coarse trabeculations (the classic “corduroy cloth” appearance). Collapse of the vertebral body.

CT findings: Vertically-oriented striations which represent reinforced trabeculae. This typical feature is called the "polka-dot pattern" (multiple dots) on axial CT and "the corduroy sign" on sagittal projections. Aggressive haemangiomas can show atypical findings as lytic areas, irregular trabecular and soft-tissue expansion.

MRI: Typical high signal intensity on T1- and T2-weighted images due to the presence of fat, high vascularity and interstitial oedema.
Atypical low-signal-intensity on T1-weighted images may be related to more active lesions with aggressive behaviour (Fig. 3a). Atypical haemangiomas may show a heterogeneous pattern on MRI (absence of fat and more vascular component).
Low-signal-intensity vertical striations (low signal on all sequences) can be seen within haemangiomas and represent coarse reinforced trabeculae (Fig. 3b).
After contrast administration, most lesions enhance (Fig. 3c).

- Outcome [1]

Treatment for haemangiomas is not necessary because they are asymptomatic. In case of symptomatic lesions, radiotherapy, balloon kyphoplasty or embolisation could be useful. Embolisation is useful in reducing intraoperative blood loss before undergoing surgery (i.e. a decompressive surgery) as well as it is an effective treatment to reduce pain.

TAKE HOME MESSAGE

- Osseous haemangiomas are mostly found in vertebrae bodies.

- They are usually asymptomatic.

- Occasionally, the may compress the spinal cord, nerve roots or show soft-tissue extension (aggressive haemangiomas).

- Embolisation is useful in reducing intraoperative blood loss before undergoing a decompressive surgery.

- Embolisation is also an effective treatment to reduce pain.