Hyperparathyroidism Flashcards
Hyperparathyroidism is more common in…
Males or females?
Females
3:1
What percentage of hyperparathyroidism patients have a single adenoma?
85 - 90%
What percentage of hyperparathyroidism patients have multiple adenomas?
2 - 4%
What percentage of hyperparathyroidism patients have hyperplasia?
6 - 8%
US is localization and not a diagnostic study in hyperparathyroidism.
True or false?
True
What needs to be done other than biochemically confirm hyperparathyroidism before localization with ultrasound?
Rule out FHH
Fractional excretion of urine calcium
When is ultrasound not useful for localizing parathyroids?
Posterior and intrathoracic locations
Name three reasons for doing an ultrasound in hyperparathyroidism?
- Localization (parathyroid adenoma)
- coexisting thyroid nodules (thyroid cancer incidence 2 - 6%)
- ethanol ablation in select patients
What is the most common frequency used for parathyroid adenomas?
7 - 10 mHz
How should the patient be positioned for parathyroid ultrasound?
With neck extended
Inferior parathyroid glands take a longer migratory route along with the thymus gland.
True or false?
True
Which pair of parathyroid glands is more constant?
Superior
Which pair of parathyroid glands migrates posteriorly?
Superior
Which pair of parathyroid glands migrates anteriorly and medially?
Inferior
Superior parathyroid: Location (%)
Carotid sheath?
1%
Superior parathyroid: Location (%)
Upper pole of thyroid?
10%
Superior parathyroid: Location (%)
Mid portion thyroid lobe?
77%
Superior parathyroid: Location (%)
Paraesophageal?
11%
Inferior parathyroid: Location (%)
Undescended?
2%
Inferior parathyroid: Location (%)
Mid thyroid?
3%
Inferior parathyroid: Location (%)
Inferior pole of thyroid?
56%
Inferior parathyroid: Location (%)
Thyrothymic ligament?
26%
Inferior parathyroid: Location (%)
Mediastinal?
9%
Parathyroid glands conform to surrounding structures.
True or false?
True
Parathyroid glands have a vascular pedicle from polar artery.
True or false?
True
Are parathyroids hypo- or hyperechoic?
Hypoechoic
What can ‘bring out’ a parathyroid lesion that is located in the tracheo-esophageal groove?
Valsalva
What is the concern when biopsy-ing a parathyroid adenoma?
Fibrosis from biopsy
When biopsy-ing a parathyroid how should the needle be moved?
Rotation and instead of jabbing
When biopsy-ing a parathyroid what gauge needle should be used?
27 G
What are the absolute contra-indications to parathyroid biopsy?
- Parathyroid carcinoma
- Familial jaw tumor - HPT syndrome
What are the relative contra-indications to parathyroid biopsy
(4)
- Anti-coagulation
- Partial or complete obscuration by vessels
- Significant respiratory movements
- Morbid obesity
When is cytology performed on parathyroid biopsies?
When PTH analysis is negative.
Is cytology useful in the identification of parathyroid adenomas?
No
PTH level from syringe washing more useful
