Thyroid Scintigraphy

What it does

Thyroid Scintigraphy reads Tc-99m pertechnetate and I-123 thyroid scans, the functional exam in the work-up of hyperthyroidism and before radioiodine therapy. Upload the thyroid images, with the uptake measurement counts when they were acquired; the run outlines the gland, measures its activity and classifies how the tracer is distributed.

The read answers the three questions the referring endocrinologist asks. Which pattern is it: Graves' disease, toxic multinodular goitre, a toxic adenoma or thyroiditis? How much tracer does the gland take up? And are the nodules functioning (hot) or non-functioning (cold), correlated with the thyroid ultrasound when it is provided?

Intended use

Decision support for a common, low-complexity but moderate-volume study: a reproducible ROI-based uptake value instead of a hand-drawn one, and a pattern classification read together with the thyroid function tests. Scintigraphy shows whether a nodule functions; a cold nodule goes on to ultrasound and cytology.

Who it is for

Nuclear-medicine physicians who report thyroid scans, endocrinologists managing hyperthyroidism and planning radioiodine therapy, and radiologists covering nuclear medicine in smaller departments.

Accepted input

• Thyroid scan: DICOM NM static images of the neck after Tc-99m pertechnetate or I-123.
• Uptake measurement (optional): the counts and timing of an uptake measurement, used for the uptake section.
• Thyroid ultrasound (optional): when provided, nodule function is matched to the nodules it shows.

Requirements

Requirement	Why
Original DICOM NM images with acquisition time	Count-based ROI quantification needs raw counts, not screenshots
Radiopharmaceutical identified (Tc-99m or I-123)	Pattern interpretation and uptake timing differ by tracer
Administered activity and its measurement time	The uptake percentage relates gland counts to the activity given
The whole gland in the field of view	Global uptake and the distribution between lobes and nodules

Optional context

Thyroid function tests (TSH, free T4, free T3), antibodies, current antithyroid or thyroid hormone medication and recent iodinated contrast can be passed in clinical_context. Medication and iodine load change uptake, so they matter when a value is low or unexpected.

The result

Section	Content
Uptake pattern	Pattern class (Graves' disease, toxic multinodular goitre, toxic adenoma, thyroiditis) and hot or cold nodules
Thyroid uptake	Thyroid uptake percentage from ROI-based quantification, with the regions and counts used
Draft report	Opt-in (options.report): an English narrative that interprets the result for the reader (findings, impression, limitations); every number is checked against the findings

The gland and nodule regions are returned with the result, so the uptake percentage can be traced to the counts it was computed from.

Standards

• Guideline: EANM/SNMMI thyroid scintigraphy and radioiodine uptake (RAIU) guideline (2019).
• Units: UCUM units for activity and time; uptake as a percentage of administered activity.
• Terminology: SNOMED CT and RadLex for findings and anatomy.
• DICOM: SR TID 1500 Measurement Report for uptake values; Key Object Selection; Encapsulated PDF.

Patterns at a glance

Graves' disease typically shows diffuse, homogeneous increased uptake; toxic multinodular goitre shows several functioning nodules with suppressed background; a toxic adenoma is a single hot nodule suppressing the rest of the gland; thyroiditis shows low uptake throughout. The result states the pattern with the uptake value that supports it.