An 80-year-old woman was referred for a painless mass arising in right side of her neck of 4 months' duration. Ultrasound revealed a multinodular goiter, but cytology confirmed a follicular carcinoma. Thyroid function was normal. Total thyroidectomy was performed with evidence of tumor infiltration into the strap muscles extending up to the right submandibular gland and right internal jugular vein, which was completely occluded. Radioiodine was considered as the treatment of choice postoperatively. This is an unusual case of SVC obstruction caused by tumor embolus diagnosed on I-131 scan.

Nuclear medicine is a functional imaging technique that images the pathophysiological processes by administration of radiopharmaceuticals that can be imaged externally by a Gamma or PET camera. Functional derangement precedes structural alteration, hence functional imaging can detect disease earlier. Imaging can be used for diagnostic and therapeutic purposes perioperatively. Preoperative assessment of fitness for surgery can be assessed by myocardial perfusion imaging; the ability to withstand the effects of lobectomy can be assessed by ventilation perfusion scan. Nuclear medicine has pre- and postoperative applications in orthopaedic, renal and hepatobiliary diseases. Nuclear medicine has an important role in the diagnosis and treatment of endocrine disorders and is a useful adjunct to other structural imaging modalities. The therapeutic radiopharmaceuticals are taken up in targeted locations, delivering a high dose of radiation to diseased tissues while avoiding radiation exposure to surrounding normal tissues. Sentinel node imaging is gaining increasing popularity because it avoids unnecessary nodal resections in breast cancer and melanomas. Postoperative assessment of renal transplants, stent patency in coronaries and detection of pulmonary emboli as a cause of postoperative breathlessness can be investigated with high accuracy. Advances in molecular imaging, development of newer radiopharmaceuticals and fusion with structural imaging are revolutionizing this modality.