2013 Radiology Exam - Spec Proced/NM Case 2

SIGNALMENT/HISTORY

  • 18-year old male castrated DSH feline
  • Increased blood pressure, weight loss, hypertrophic cardiomyopathy

IMAGING STUDIES:

  • Tectnetcium-99m pertechnetate thyroid scan - LEAP collimator
  • Tectnetcium-99m pertechnetate thyroid scan - Pin-hole collimator

OBSERVATION
Tectnetcium-99m pertechnetate thyroid scan - LEAP collimator

  • Opposite lateral and ventral views of the neck and thorax were made. A focal intense area of uptake is observed on the midline of the neck with smooth margins.
  • Opposite lateral views of the thorax show a linear area of uptake on the left lateral view that is not observed on the right lateral or ventral views. Normal uptake is observed in the heart and stomach.
  • No evidence of ectopic thyroid tissue in the base of the tongue, neck or mediastinum.

Tectnetcium-99m pertechnetate thyroid scan - Pin-hole collimator

  • A single ventral views shows the intense area of uptake is located in the left lobe of the thyroid. A faint area of uptake is observed in the right lobe of the thyroid gland.

SYNTHESIS

  • Pattern of uptake most consistent with bilateral nodular hyperplasia/multinodular adenomas
  • Transient esophageal activity due to swallowing of saliva or gastroesophageal reflux

CASE MANAGEMENT

  • Medical treatment - methimazole or I-131 treatment were accepted as this recommendation would vary

Challenges

  • This case was handled well by most candidates with a good overall score.
  • Identification of transient esophageal activity due to swallowing of saliva or gastroesophageal reflux was most frequently missed aspect.
  • Faint activity of the right lobe indicates abnormality in right lobe as well. Normal thyroid tissue would be completely suppressed and show no uptake.
  • Some difficulty correctly identifying the views obtained (right vs left lateral).