Thyroid (Both I-123 & I-131)
PROCEDURE: THYROID IMAGING (Both I-123 and I-131)
SECTION: ENDOCRINOLOGY 3.1
ORIGINAL DATE: 4 - 3 - 00
DATE REVISED: 10 - 19 - 16
- Evaluation of palpable nodules.
- Evaluation of abnormal gland to palpation, but without definite nodules.
- Evaluation of patients who had irradiation of the head and neck in childhood with or without palpable nodules.
- Evaluation for ectopic thyroid tissue, e.g. Struma Ovarii (image over pelvis) and lingual thyroid (image upper neck and jaw).
The provider will interview patient regarding the following contraindicated meds. The patient must be off the following for at least:
- Thyroxine (T‑4): 6 wks
- Triiodothyronine (T‑3): 2 wks
- Propylthiouracil (PTU): 3 days
- Tapazole (Methimazole): 3 days
- Iodinated contrast: 4 wks
Other substances that might interfere with accurate uptake:
- Kelp (4 wks)
- herbal preparations
- certain vitamins/minerals (4 wks)
- Lugol’s solution and SSKI (4 wks)
- some cough medicines (4 wks)
- perchlorate (4 wks)
- pertechnetate (1 wk).
Reference: Dr Caplan 11/2008 +7/2013
Exam time length: 60 minutes
Patient Preparation: See contraindications above.
Radiopharmaceutical & Dose:
- 123 I dose: Adult: 200 – 400 microCi (2-100 microCi Caps)
- Substernal thyroid I 123: 300 microCi (3 -100 microCi Caps)
- Pediatric: 100-200 microCi (1-100 microCi Cap)
- 131 I dose: 100 – 150 microCi
Staff perform bioassay within 3 days after administration of any of the following:
- any dose of liquid I-131; or
- dose >100mCi I-131 in capsules; or
- total dose administered by same tech in one 24hr period >100 mCi I-131 in capsules
Administration Technique: Oral
STATIC ACQUISITION PARAMETERS: Infinia
Time interval between tracer injection & imaging: Provider will specify 4 hour or 24 hour exam
- 123 I __LEAP
- 131 I___Hi energy
Patient position: Supine, head first
- 123 I __159 KeV
- 131 I___364 KeV
Matrix: 128 x 128 for both energies
- Ant, 1.5 zoom, 5 min
- Ant w/ marker, 1.5 zoom, 30 sec
- Ant, 3.0 zoom, 10 min
- RAO/LAO, 3.0 zoom, 10 min, use L mode, pan X 26, pan Y -13
- Ant with marker on SSN, may also mark any palpable nodules,
- Mark chin & SSN on post thyroidectomy scan, Transmission image may be taken if needed to define activity seen,
- Ant with zoom
- RAO/LAO with zoom
- If needed do chest view for sublingual thyroid (1.5 zoom, 10 minutes)
Screen caps to make: Add together Ant & marker image(s), display result along with all other images taken, Measure both lobes with electronic ruler and move off to side, 6 on 1, label all views and landmarks. Chest image may be included for sublingual thyroid.
Send to FUJI: Screencaps: type the %uptake on our thydoid uptake/scan screen captures