대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Primary Hyperparathyroidism due to Parathyroid Adenoma

Radiologic Findings

Anterior rib ends of both hemithoraces are widened.

Subperiosteal resorption is seen in both scapula, acromial end of the clavicle, and the shaft of the clavicle. Irregularity of the manubriosternal junction is seen.

Subligamentous resorption is seen in both coracoclavicular joint.

Sclerotic change is seen at the upper and lower end plates of T-spine .

Surgical exploration of the neck showed parathyroid mass, which was confirmed to be parathyroid adenoma.

Brief Review

Excessive production of PTH, termed hyperparathyroidism is classified as primary, secondary, or tertiary in form. Primary hyperparathyroidism, due to autonomous hypersecretion of PTH, usually occurs in the setting of a parathyroid adenoma (80%) but can also be seen with parathyroid gland hyperplasia (15%?20%) or carcinoma (0.5%). Secondary hyperparathyroidism results from stimulation of the parathyroid glands as a response to hypocalcemia or due to apparent insensitivity of the parathyroid glands to elevated serum calcium levels and dysregulation of the normal negative feedback loop (pseudohypoparathyroidism). Tertiary hyperparathyroidism is seen in cases of secondary hyperparathyroidism in which the parathyroid glands continue to function autonomously despite correction of the initial cause, resulting in hypersecretion of PTH in the setting of normal calcium levels.

The classic imaging features of advanced primary hyperparathyroidism are also less frequently seen today. Generalized osteopenia is the most common imaging finding in primary hyperparathyroidism. Only very rarely encountered in primary hyperparathyroidism, diffuse or localized osteosclerosis is a more common finding in secondary hyperparathyroidism. When involving the spine, sclerosis can produce a striped appearance, the so-called ?rugger jersey? spine. Subperiosteal bone resorption is a common finding of advanced hyperparathyroidism, most often seen involving the hands and the feet.

Other areas of bone resorption are seen at sites of high bone surface area and include subchondral locations, often best appreciated at the sacroiliac, acromioclavicular, sternoclavicular, and temporomandibular joints, the symphysis pubis, and the patella. Resorption of subligamentous and subtendinous bone occurs most often at the femoral trochanters, the ischial tuberosities, the calcaneal insertions of the plantar aponeurosis and Achilles tendon, the inferior margin of the distal clavicle, and the tuberosities of the humerus. Intracortical, endosteal, and trabecular bone resorption can also be present. Brown tumors, also known as osteoclastomas, are eccentrically located and often expansile lesions resulting from amassing osteoclasts and fibrous tissue. Chondrocalcinosis is a nonspecific finding that has a higher prevalence in primary rather than secondary hyperparathyroidism. Although also having a higher prevalence in primary hyperparathyroidism, brown tumors are more frequently encountered in the setting of secondary hyperparathyroidism due to the greater prevalence of this condition. Soft-tissue calcification and periostitis are among the radiographic findings more commonly seen in secondary hyperparathyroidism.

References

McDonald DK, Parman L, Speights VO Jr., Best cases from the AFIP: primary hyperparathyroidism due to parathyroid adenoma., Radiographics. 2005 May-Jun;25(3):829-34.

Keywords

Chest wall, Sternum, Metabolic and storage lung disesae,