Post on 19-Feb-2022
Col. Trirat Boonya-ussadorn
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer
Treatment of bone pain in bony metastasis
I-131 uptake : 2 hrs and 24 hrs.
Normal at 24 hrs = 15-30% (variable)
Grave’s disease 60-80%
Toxic multinodular 50-60%
Drug effect on thyroid uptake
Thyroid hormone
Antithyroid drug: PTU, MMI
Vitamin
Cordarone
Contrast media
Food effect on thyroid uptake
Sea food
Iodinated salt
Discontinue ATD and foods effect on thyroid uptake 1 wk.
NPO
Oral administration of tracer dose of I-131 10 uCi
I-131 uptake 2 hrs and 24 hrs.
Differentiated low and high uptake of
thyrotoxicosis
Using for calculation of administrated
dose of RAI for treating hyperthyroidism
Confirmation of hyperthyroidism: DDx
hyperthyrodism vs thyroiditis
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer
Treatment of bone pain in bony metastasis
Radiopharmaceuticals 99mTc-pertechnetate
I-131
I-123
Indications Thyroid nodules
Ectopic thyroid
Thyroiditis
Graves’ disease
Multinodular toxic goiter (Plummer’s disease)
Solitary hyperfunctioning adenoma (toxic adenoma)
Thyroid cancer
2 ways for performing thyroid scan
Tc-99m Pertechnetate ( IV injection )
dose 3-5 mCi: 140 keV, half life 6 hrs
I-131 (oral): 364 keV, half life 8 days
Tc-99m pertechnetate
Total body scan (TBS) or Whole body scan (WBS) with I-131
ใชใ้นการตรวจและติดตามผลการรกัษาผูป่้วยที่รกัษาดว้ยไอโอดนีรงัส ี(I-131)
ซ่ึงอาศยัรงัสเีบตามา Irradiate เซลลข์องตอ่มไทรอยดท์ี่ เป็นมะเร็งใหห้มดไป การท าสแกนแบบน้ีจะสามารถบอกไดว้า่ยงัมเีซลลม์ะเร็งของตอ่มไทรอยด์
หลงเหลืออยูห่รือไม ่ถา้มกีารแพร่กระจายไปที่ อ่ืนจะเหน็ไดจ้ากภาพสแกนจะไดท้ า
การรกัษาซ า้จนไมม่เีซลลข์องตอ่มไทรอยดเ์หลืออยู ่
off Levothyroxine (Eltroxin, Euthyrox) 1 mo
low iodine diet 1 wk
NPO
Administration of tracer dose
1-5 mCi
Waiting for 48 – 72 hrs
Scan the whole body
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer
Treatment of bone pain in bony metastasis
Hyperthyroidism
Well-diff CA thyroid
Radiopharmaceutical
for specific tumor
Treating bone pain of
metastatic disease
I-131
I-131
I-131 MIBG
Sr-89
Sm-153 EDTMP
Oral form : solution, capsule
I-131---- Xe-131+ gamma ray (γ) 364 keV +
beta ray (β) 192 keV
Half life = 8.06 days
Rx:
1. Hyperthyroidism : Graves’ disease, Toxic
multinodular goiter, Toxic adenoma
2. Well-differentiated thyroid CA: Papillary,
Follicular
Physiologic I-131 uptake :
1. Thyroid gland
2. Salivary glands
3. Gastric mucosa
Excreted via urine and can cross placenta
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer
Treatment of bone pain in bony metastasis
Thyrotoxicosis = increased TFT
Hyperthyroidism = Thyrotoxicosis from
hyperfunctioning thyroid
Diffuse toxic goiter (Graves’ disease)
Toxic multinodular goiter (Plummer disease)
Toxic adenoma
Diffuse enlargement of thyroid gland
Exophthalmos
Pretibial myxedema
เหน่ือยงา่ย ใจสั่น มือสั่น
กนิจุ หิวบอ่ย
น ้าหนักลด
ขี้รอ้น เหง่ือออกมาก
ทอ้งเสยี
ประจ าเดือนนอ้ย
infertility
AF
CHF
Periodic paralysis
( hypoK+ )
Exophthalmos
Eyelid retraction
Osteoporosis
Indication of I-131***
1. Medication failure
> 2 yrs
High dose of ATD
Recurrence
Poor compliance
Drug allergy: agranulocytosis
2. Surgical failure
Withdraw drug and food effected 1 wk.
NPO
Thyroid uptake 2 and 24 hours
Oral administration of I-131
F/U in the next 3 months
Admit in hospital is not necessary.
FT3 or T3 : Hyperthyroid
FT4 : Hypothyroid, Eltroxin/ Euthyrox
(Levothyroxine, LT4)
TSH
Full effect of RAI will occur within 3
months
Euthyroid
No remission
Hypothyroidism
Nausea and vomiting (radiation sickness)
Transient hyperthyroidism or thyroid storm
Thyroiditis (neck swelling)
Induce malignancy ?
Induce teratogenic effect ?
Induce infertility ?
***PREGNANCY*** LACTATION
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer Treatment of bone pain in bony metastasis
Well differentiated CA thyroid***
Poorly differentiated CA thyroid
Anaplastic CA
Medullary CA
Papillary CA
Follicular CA
Metastatic disease from well diff CA
Post–Op for 4-6 wks
+/- Dx Total body scan
(DxTBS with I-131)
Calculated dose of RAI
Oral administration of RAI
Admit until radiation dose is decreased to
accepted level.
Post I-131 TBS before discharged
Home med : Thyroid hormone (Eltroxin, Euthyrox,
Levothyroxine/LT4)
F/U: stimulated Tg +/- TBS with I-131 in 6 months
Preparation for TBS
Induce hypothyroidism
***TSH stimulation***
by discontinuing thyroid hormone 4-6 weeks.
Avoid high iodine diet and drug 1 wk.
Serum thyroid hormone (FT4)
TSH
Thyroglobulin (Tg)
Antithyroglobulin (TgAb)
TBS shows negative result
Continue thyroid hormone
TBS shows residual tumor or thyroid tissue
Repeat dose of RAI treatment
TBS post I-131 treatment 100-200 mCi
Diagnosis TBS with I-131 1-3 mCi
RAI for treatment of CA thyroid usually is high dose ,100 – 200 mCi
Neck swelling
Sialadinitis
Nausea, vomiting, radiation sickness
Hemorrhage (CNS, spinal)
LATE EFFECT
Hypothyroidism
Lung fibrosis
Induce malignancy ?
Induce teratogenic effect ?
Induce infertility ?
1. Thyroid study in Nuclear Medicine
(cont.)
Thyroid uptake
Thyroid scan: for thyroid nodule (99mTc-
pertechnetate), CA thyroid (I-131)
2. NM radionuclide therapy
I-131 in Hyperthyroidism
I-131 in thyroid cancer
Treatment of bone pain in bony metastasis
Sr-89
Pure beta ray
Can be used as OPD case
Effective treatment in bone pain due to
bone metastasis from CA prostate, breast
cancer
No serious side effect
Sm-153 EDTMP
Emit both gamma and beta ray
Preparation : Bone scan, blood chemistry
especially CBC .
Patient should be admitted at lease 4 hrs
After treatment for 24-72 hrs, the patient
should be performed scan