Determining the Minimal Required Radioactivity of 18F-FDG for Reliable Semiquantification in PET/CT Imaging: A Phantom Study.

Unlabelled: In pursuit of as-low-as-reasonably-achievable (ALARA) doses, this study investigated the minimal required radioactivity and corresponding imaging time for reliable semiquantification in PET/CT imaging.

Methods: Using a phantom containing spheres of various diameters (3.4, 2.

Using SUV as a guide to 18F-FDG dose reduction.

Unlabelled: This article explores how one can lower the injected (18)F-FDG dose while maintaining validity in comparing standardized uptake values (SUVs) between studies. Variations of the SUV within each lesion were examined at different acquisition times.

Methods: Our protocol was approved by either the Human Investigation Committee or the Institutional Review Board.

What is the role of dosimetry in patients with advanced thyroid cancer?

Purpose Of Review: Pretreatment dosimetry prior to I-131 treatment for patients with advanced differentiated thyroid cancer will provide critical information for optimizing dosing regimen for effectiveness and safety. The review briefly summarizes relevant information and updates the current advances.

Recent Findings: I-124 positron emission tomography-computed tomography (PET-CT) with anatomical cross-section imaging provides a better assessment of lesional dosimetry in contrast to traditional I-131 whole body scan with planar imaging.

The utility of I-123 pretherapy scan in I-131 radioiodine therapy for thyroid cancer.

Background: There is a growing belief that a pretherapy scan yields little or no additional information that would impact on radioiodine ablation dosing. In addition, there is some concern regarding on the stunning effect of a pretherapy scan, especially when I-131 radioisotope is used for imaging. We hypothesized that a pretherapy scan provides invaluable information on the amount of thyroid remnant, sometimes indicating the need for two-step I-131 ablation.

Rapid correction of bone mass after parathyroidectomy in an adolescent with primary hyperparathyroidism.

Context: Primary hyperparathyroidism is rare in children. Absence of specific symptoms and limited biochemical evaluation in children has led to lengthy delays in diagnosis with the potential for damage to the kidneys and skeleton.

Setting: The setting involved a private practice referral to a large tertiary care center.

Recombinant human thyroid-stimulating hormone as an alternative for thyroid hormone withdrawal in thyroid cancer management.

Purpose Of Review: The purpose of the review is to summarize the current findings of using recombinant human thyroid-stimulating hormone (rhTSH, also known as Thyrogen) as adjuvant stimulation for diagnostic monitoring, thyroid remnant ablation, and treatment of metastatic thyroid cancer.

Recent Findings: A negative Thyrogen-stimulated thyroglobulin level has a negative predictive value of up to 98.5%.

Unusual case of amiodarone-induced thyrotoxicosis: "illicit" use of a technetium scan to diagnose a transiently toxic thyroid nodule.

Objective: To present an unusual case of amiodarone-induced thyrotoxicosis (AIT) associated with an autonomously functioning thyroid nodule, which was detected by means of a technetium scan; review the existing literature regarding the association of AIT with autonomous thyroid nodules; and explore the use of radioisotope imaging studies in patients with AIT.

Methods: We describe a 62-year-old man with paroxysmal atrial fibrillation, receiving long-term amiodarone therapy, who was referred by his cardiologist for evaluation of abnormal thyroid function tests. He was found to have an unusual case of AIT, associated with an autonomously functioning thyroid nodule.

Contemporary imaging for thyroid cancer.

Thyroid nodules are extremely common in the adult population of the United States, and the incidence of thyroid cancer continues to increase. Preoperative ultrasonography is a crucial component of the work up of thyroid nodules. Recent studies evaluating (18)F-2-fluoro-2-deoxy-D-glucose-positron-emission-tomography, with or without simultaneous computed tomography imaging, are encouraging for its potential utility in thyroid cancer in patients who have an elevated serum thyroglobulin level and a negative (131)I scan.

Reliability of lymphatic mapping after wide local excision of cutaneous melanoma.

Background: Since the advent of sentinel lymph node (SLN) biopsy, patients with cutaneous melanoma have been referred to surgeons for consideration for SLN biopsy, sometimes even after the wide local excision (WLE) of the primary melanoma has been performed. This has raised the question of the reliability and validity of a lymphoscintigram performed for lymphatic mapping of the SLN after there has been anatomic rearrangement of the skin following the WLE of this primary melanoma.

Methods: We conducted a prospective study of 20 consecutive patients with cutaneous melanomas with thickness less than 1.

Low-dose P32 therapy in essential thrombocythemia.

We present a case of an 85-year-old woman with medically refractory essential thrombocythemia and subsequent venous thrombosis. She received conservative phosphorus-32 sodium phosphate therapy for 3 mCi, approximately half the usual dose. One month later, she received a second intravenous phosphorus-32 treatment of 3.

Artifactual spinal metastases imaged by PET/CT: a case report.

A 55-y-old patient with multiple myeloma presented for restaging after chemotherapy and radiation. The patient had undergone vertebroplasty of multiple thoracic vertebrae because of painful compression fractures. The 18F-FDG PET images showed increased activity at the T8 and T10-T12 vertebral bodies.