Soft Tissue Calcification

SOFT TISSUE CALCIFICATION

By Dr. KM Liau

Soft tissue calcifications are usually caused by one of the following 5 entities.

These are listed below in order of prevalence.

(Note: Do not confuse soft tissue calcification with bone calcification. Bone calcification will be dealt in Bone Tumour Radiology)

Types of soft tissue calcification

1. Dystrophic Calcification

2. Metastatic Calcification

3. Calcinosis

4. Chondrocalcinosis

5. Synovial Chondromatosis.

Dystrophic calcification

Calcification in damaged or degenerating tissue by small to large amorphous calcium deposit.

Not associated with metabolic disorder.

Almost every calcification that one sees in the soft tissues in actual radiographic practice is due to dystrophic calcification.

They have a prevalence of 95-98% out of all soft tissue calcification.

Differential diagnosis of dystrophic calcification

Mnemonic = VINDICATE (VINDAT)

V = Venous - Phlebolith

I = Infection - Cysticercosis

N = Neoplasm - Osteosarcoma

D = Drugs - Vitamin D overdose

A = Autoimmune - Dermatomyositis

T = Trauma - Hematoma, Heterotopic ossification

Vascular calcification - Phlebolith in the pelvic vein with characteristic central lucency

Cysticercosis - Patient with multiple "rice grain" calcifications which are oriented along the direction of the muscle fibers.

A child with conventional intramedullary osteosarcoma of distal femur.

Hypervitaminosis D - Calcification over the elbow

Dermatomyositis-46 year old female with dermatomyositis and extensive soft tissue calcifications about the knee and hip.

Calcified hematoma - an example of dystrophic calcification

Dystrophic calcification of Achilles tendon due to recurrent trauma and tendinitis.

Heterotopic ossification of the right hip in a patient who sustained head injury

Metastatic Calcification

Calcification of normal tissue.

Frequently associated with a metabolic disorder.

Can result from any process with an elevated calcium-phosphate product.

Entities such as renal failure, hyperparathyroidism, sarcoidosis, milk-alkali syndrome, etc. can lead to metastatic calcifications.

These are often fine and diffuse throughout the soft tissues.

Metastatic calcification of the lung secondary to chronic renal disease and hyperparathyroidism.

Calcinosis

Calcification of cutaneous, subcutaneous or deep connective tissue.

Not associated with metabolic disturbance.

May be associated with with collagen-vascular disease.

3 Types:

1. Calcinosis circumscripta

2. Calcinosis universalis

3. Tumoral calcinosis

Calcinosis circumscripta (localized deposition of calcium in small in subcutaneous tissue) in Scleroderma

Calcinosis universalis - Diffuse cutaneous, subcutaneous and sometimes muscular calcification seen in dermatomyositis

Tumoral Calcinosis

Tumoral calcinosis is a relatively rare disorder most commonly seen in people of African descent.

The etiology is uncertain.

The histologic appearance is characterized by densely loculated masses of calcific debris and fluid enclosed by fibrous tissue.

Lesions grow quite slowly and rarely cause pain unless there is nerve involvement.

Surgical removal is the treatment of choice.

Incomplete resection leads to recurrence.

Tumoral calcinosis in a 59 year old black woman who presented with hip pain

Elderly female with tumoral calcinosis of the hand and wrist.

Same elderly female with tumoral calcinosis of both hip joint.

Chondrocalcinosis

Calcium pyrophosphate dihydrate deposition disease (CPPD) is usually associated with chondrocalcinosis.

This typically appears as a fine white line overlying the hyaline articular cartilage.

CPPD is also associated with calcifications in the soft tissues of the spine.

Chondrocalcinosis of the articular and fibrocartilage of the left knee in a patient with calcium pyrophosphate dihydrate deposit

Synovial chondromatosis

Affects knee, hip and shoulder joint.

Tends to be mono-articular.

Due to metaplasia of synovial connective tissue.

Uncommon cause of loose bodies.

Biopsy shows active synovial proliferation.

Synovial osteochondromatosis in a 24-year-old man with hip pain. Radiograph shows multiple small, dense, punctate calcifications

Synovial chondromatosis of shoulder