Vertebral hemangiomas (spinal angiomas)
Vertebral hemangiomas (spinal angiomas) are the most common benign neoplasms of the spine. Vertebral angiomas, as a rule, are asymptomatic and are detected by chance (according to their characteristic external features) during diagnostics (MRI, CT, X-ray) for other diseases and pathological conditions (back pain, infection, or spinal injury, etc.) ). Spinal hemangiomas are benign tumors that are most common in the middle (thoracic) and lower (lower back) parts of the spine.
Epidemiology of vertebral hemangioma
Hemangiomas of the vertebrae are very common and occur in about 10 percent of the population (based on autopsy data). Most hemangiomas are detected on standard radiographs of the spine. Often, small hemangiomas cannot be detected on radiographs and are visualized with more modern methods of radiation diagnostics, such as CT or MRI, or with autopsy. Hemangiomas most often form in adults between the ages of 30 and 50. The incidence of vertebral hemangiomas for unknown reasons more often prevails among women and is most symptomatic in the 4th decade of life.
The clinical presentation of vertebral hemangioma
Most vertebral hemangiomas are asymptomatic during life. Destruction of the vertebral body or impact on the adjacent intervertebral foramen (the place where the nerve root exits the spinal canal) is the most common cause of pain symptoms in patients. Increased physical activity (exercise, household stress, etc.) can cause pain. This is most often associated with an increased axial load on the body of the vertebra affected by the tumor. In most cases, vertebral hemangiomas do not show any symptoms. Symptomatic vertebral hemangiomas account for less than one percent of all hemangiomas and are more common in women than in men. In the absence of timely treatment, symptomatic vertebral hemangioma in the future can cause serious neurological disorders in the patient.
Symptoms of vertebral hemangioma
Most hemangiomas are asymptomatic, but if symptoms are present, they can manifest as:
- back pain
- pain spreading along the nerve due to inflammation or irritation of the nerve root
- symptoms of compression (compression) of the spinal cord
Pathophysiology of vertebral hemangioma
Vertebral hemangiomas consist of vascular cavities, which, due to their volume, cause displacement of the surrounding bone tissue. In rare cases, especially with the capillary type of hemangioma, lytic erosion of the vertebra towards the epidural space can be observed. Hemangiomas grow slowly and in most cases are asymptomatic.
Most vertebral hemangiomas occur in the thoracic spine, but can also be found in other parts of the spinal column.
Diagnostics of the vertebral hemangioma
Radiographic characteristics of vertebral hemangioma
If a hemangioma is suspected, the doctor will order an x-ray of the spine to check for a characteristic bone change in the vertebral body (trabecular cancellous pattern). Trabeculae or cancellous bone are lattice structures in the bone of the vertebral body. X-ray of the spines reveals the classic picture of "corduroy tissue", which is characteristic of a hemangioma.
Computed tomography (CT) of the spine shows changes in vertebral hemangioma.
Computed tomography (CT) of vertebral hemangioma
Computed tomography of the spine (CT) on an axial slice reveals dotted inclusions, resembling in appearance "peas", which arise as a result of thickened trabeculae of the vertebral bodies. If these changes are present, magnetic resonance imaging of the spine (MRI) is done as the next diagnostic test to show if the tumor is spreading down the spine, into the spinal canal, or causing compression of the spinal cord.
Magnetic resonance imaging (MRI) of vertebral hemangioma
Magnetic resonance imaging of the spine (MRI) shows the soft tissue components of the hemangioma (in the form of fat and water) better than computed tomography (CT). Thickened trabeculae of the vertebral bodies are visualized on MRI images as a signal with a low level in T1 and T2 modes:
- T1 mode - a high-intensity signal from a hemangioma due to the presence of a fat component
- T2 mode - bright/high intensity signal from hemangioma (usually more than in T1 mode), due to high water content
- T1 C + mode (with contrast) - a significant improvement is seen due to the high vascularization of the hemangioma
Differential diagnosis of vertebral hemangioma should be carried out with metastases of malignant tumors from other organs and tissues.
Tumor metastases on spine magnetic resonance imaging (MRI) images usually have a reduced signal intensity in T1 and an increased signal intensity in T2 modes.
An MRI of the spine can also show the extent of spinal nerve damage and can help in planning a patient's surgical treatment.
Aggressive vertebral hemangioma
Unlike the common hemangiomas of the vertebrae, aggressive hemangiomas can expand the vertebral body from the inside, invade the paravertebral soft tissues, and also reach the spinal canal, causing compression (compression) of the spinal cord or pathological vertebral fractures.
On MRI of the spine, the tumor may resemble metastases, but the presence of thickened trabeculae in the affected vertebral bodies makes it possible to differentiate aggressive hemangioma from other malignant neoplasms.
Computed tomography of the spine (CT) is more sensitive than MRI for describing typical bone changes in aggressive hemangiomas, such as pinpoint sclerosis, or "pea" spots on transverse (axial) images, and vertical lines that look like "corduroy fabrics", "lattice rods" or "honeycomb" in sagittal images.
Treatment of vertebral hemangioma and subsequent prognosis
Treatment for most of the identified vertebral hemangiomas is not required. Treatment is necessary if the patient has symptoms of neurological deficit or severe pain symptom. In the presence of such symptoms, there are several options for possible treatment, which are selected individually: radiation therapy, balloon kyphoplasty or intravascular transarterial hemangioma embolization followed by laminectomy, etc. With open surgery, bleeding can be a serious complication, so care must be taken during surgery.
In the case of symptomatic hemangioma, surgical removal (resection) of this tumor from the affected vertebra is performed, as well as radiation therapy to treat severe pain symptoms. Ethanol can also be injected into the tumor (it causes necrosis of the hemangioma tissue with its subsequent scarring), or a laminectomy operation (for decompression of the spinal canal) can be performed.
Treatment for hemangioma depends on the size and location of the tumor. With the timely use of a combination of procedures in the form of blocking blood flow in the tumor (embolization), surgical removal of the tumor, and radiation therapy, it is possible to achieve a significant improvement in the patient's condition.
Radiation therapy is effective in treating pain symptoms caused by vertebral hemangioma. Also, in the treatment of pain symptoms, it is effective to inject ethanol into the thickness of the tumor under fluoroscopic control. Another treatment option is tumor embolization with bone cement followed by removal of the bones of the vertebral arch (laminectomy), or complete removal of the vertebra (vertebrectomy) in the case of aggressive hemangioma.