ramanna, saturday, session viii
TRANSCRIPT
NUCLEAR MEDICINE IMAGING OF PARATHYROID
LALITHA RAMANNA M.D.Little Company of Mary Hospital,Torrance , CA
34 th Annual Western Regional SNM mtgOCT29-NOV1, 2009, Monterey, CA
Parathyroid GlandsHistory
• 1852-first identified in rhinoceros.• 1898- tetany first described in cats/dogs
after removing parathyroid glands• 1898-histology described• 1903-relation between bone dis. ¶thy.• 1914- discovery of parathyroid hyperplasia in response to low ca diet.• 1921- Measure of serum calcium
ParathyroidHistory( contd)
• 1926-first parathyroid surgery humans(Mandl)
• 1958-isolation of purified PTH(Rasmussen& Craig)
84 chain aminoacid polypeptide
• 1960’s RIA for PTH
ANATOMY OF PARATHYROID GLANDS
-Wt=30 mg (10-70 mg).-Size = 5x3x1mm.-Develop from 3rd and 4 th ------bronchial pouches at 6 wks gestation - Migrate to neck at 8 wks.-Blood supply: Inferior thyroid artery - Inferior glands are more variable postition
Hypercalcemia.
• Malignancy: Multiple myeloma Lymphoma, Leukemia Bone metastases Production of PTH/Prostaglandins by other tumors.
• Drugs: Thiazide diuretics Vitamin D toxicity Milk- alkali syndrome
• Endocrine: Hyperparathyroidism Hyperthyroidism Acromegaly Adrenal insufficiency
• Miscellaneous: Sarcoidosis Tuberculosis Immobilization
Anatomy of Parathyroid Glands.
• Autopsy study 503 Cases– 4 glands –------84%– Supernuerary- 13%– 3 glands 3%– Symmetric 80%
– Anatomic distribution fairly consistent.
Surgery, Jan 1984
“ Renal Stones, painful bones and
Abdominal Groans”to
“ Vague Neuromuscular and behavioral symptoms or even
without any symptoms”
Hyperparathyroidism: Symptoms and signs
• Renal stones - 63.4%• Bone disease- 24.0%• Peptic ulcer - 7.8%• Asymptomatic- 5.4%• Fatigue 3.0%• Mental confusion2.4%
• Pancreatitis– 2.3%• Hypertension-1.4%• Palpable neck-1.3% mass• Multiple endocrine syndrome 1.1%• Pseudogout 0.6%
Parathyroid adenoma
• Single adenoma (80-90%)• Double adenoma(5-10%)• 4 gland hyperplasia (10-15%).
Neck Surg.2005;132:359-372
Parathyroid adenoma LocalizationMehods
• Radionuclide Techniques• High resolution Ultrasound • CT/MRI• Cine- Esophagography• Mediastinography• Arteriography• Selective Venography( PTH assay)• Thermography
Parathyroid Imaging Agents.Se-75 Methionine TL-201 Tc-99m sestamibi
TI/2 120 days 73 hrs 6hrs
PhotonEnergy(kev) 136,265,280,560 69-83,135,169 140
Uptake Incorporation Potassium analog -non-specificMechanism into protein Intracellular -blood flow -Mitochondria
Dosimetry of Parathyroid Imaging.
Radiopharmaceutica Activity EDV(mSv)
Tc-99m pertechnetate 75 1.0
1-123 20 3.0
Tc-99m Sestamibi 200 2.4(M) 3.0(F)
Tl-201 75 25
Parathyroid Surgery( controversial)Consensus Development Conference Panel
(Annals of Internal Medicine,Vol 114 no 7) April ,1991.
• Endocrinologists, surgeons, Radiologists, Epidemiologists and primary health care providers• Symptomatic- surgery• Asymptomatic- not always surgery• If serum ca is elevated careful surveillance If renal and bone status is close to normal • Preoperative localization without prior surgery is rarely indicated and not proven to be cost effective
Parathyroid adenoma localization :Various Protocols
• Tl-201/ Tc /i-123 subtraction.• Dual phase TC-99m planar Sestamibi .• Dual phase Tc-99m pin hole sestamibi• Dual phase Tc-99m Sestamibi with Tc thyroid or
123 thyroid( subtraction )• Dual phase pin hole Tc-99 m Sestamibe with Tc-
99m or 123 thyroid ( subtraction)• SPECT• SPECT with thyroid subtraction • SPECT/CT
Tc-99m-Tl-201 Parathyroid ScanLiterature Review
Radiology 1987: 162:133-137
• No. of papers=14• No. of scans= 396• No. operated=317
• Sensitivity=82%• Accuracy=78%• PPV =94%• FP =5%
Disadvantages of Tl/Tc scan
• Limited dose of Tl-201
• Poor physical properties
• Proloned pt immobilization
• Pt motion
• Processing artifacts
J nucl Med 1992;33:313-318
J Nucl Med 1992;33:1801-1807
400mg
3.5 gm
300mg
Parathyroid Imaging Protocol.• SNM procedure guide lines approved June
2004.( SPECT/CT not mentioned)
• 3 mci. Tc-99m pertechnetate i.v.• Anterior 10 minute Neck/chest image• 25 mci.Tc-99m Sestamibi i.v.• Serial anterior neck/chest images 20, 30, 40, 60 min and 2-3 hr delay• Computer assisted pertechnetate subtraction
from sestamibi • Additional delays, SPECT/CT and pinhole
optional
10 min with subtraction
3 hrs
Tc-99m 10 min Mibi 10 min Mibi 3hrs
SPECT/CT
59 yr old man with hypercalcemia and renal stone on CT.
TcO MIBI Subtraction
SPECT/CT
Thyroid Spect/ct: Thyroid
US
Left thyroid lobe
TcO 10 min Mibi
30 min Mibi 3 hr Mibi
Pt on exogenous thyroid medic.
AXIAL CORONAL
SAGITAL
Tc-99 m Mibi 10 min Mibi 3 hrs
10 min subtraction
SPECT/CT
Tc O MIBI 10 MIN MIBI 3HRS
Transmission
PLANAR PINHOLE
7GM ADENOMA
Early Delay
The Usefulness of Neck Pinhole SPECT as a Complementary Tool to Planar Scintigraphy in Primary and Secondary
Hyperparathyroidism Angela Spanu, MD1, Antonio Falchi, MD1, Alessandra Manca, MD2, Pietro
Marongiu, MD1, Antonio Cossu, MD2, Nicola Pisu, MD1, Francesca Chessa, MD1, Susanna Nuvoli, MD1 and Giuseppe Madeddu, MD1
J Nucl Med 2004;45:40-48
Sen, of 98% vs88%
Ectopic Parathyroid adenoma
• Mediastinal
• Retropharynx
• Carotid sheath
• thymus
Mediastinal Adenoma
Planar
coronal
sagital
SPECT
Early
Delay
MULTIPLE ADENOMA
DIFFUSE HYPERPLASIA
23 yr old man with decreasedrenal functionSerum ca highSerum PTH 1800
Parathyroid Imaging:Advantages prior to surgery
• Reduces operative tim/anasthesia.
• Reduces need for ext. exploration.
• May reduce operative morbidity.
• Localization important in re-explorations.
Overall ResultsEARLY LATE SUBT SPECT Early +
LatePLANAR ALL
Sens66%* 78%* 81%* 83%* 84%* 88% 90%
Spec93% 91% 93% 84%* 90% 87% 89%
Acc 79%* 85%* 87%* 83%* 87%* 88% 89%PPV
91% 91% 93% 85%* 90% 88% 90%NPV
71%* 79%* 81%* 82%* 83%* 87% 89%T >1 >2 >2 >2 >2 >2 >2
* p<0.05 versus ALLSubt: Subtraction; T: Threshold
Nichols, Radiology 2008;248(1):221-32.
False Negative
• Small adenomas
• Small hyperplastic glands
• Technical
• Histology
• Multiple adenomas
FALSE POSITIVE
• Thyroid CA(nodules)
• Multinodular Goiter
• Chronic thyroiditis
• Thymus remnant
• Lymph nodes