Radiofrequency ablation (RFA) is used to treat pulmonary malignancies. Although preliminary results are suggestive of a survival benefit, local progression rates are appreciable. Because a patient can undergo repeat treatment if recurrence is detected early, reliable post-RFA imaging follow-up is critical. The purpose of this article is to describe (a) an algorithm for post-RFA imaging surveillance; (b) the computed tomographic (CT) appearance, size, enhancement, and positron emission tomographic (PET) metabolic activity of the ablation zone; and (c) CT, PET, and dual-modality imaging with PET and CT (PET/CT) features suggestive of partial ablation or tumor recurrence and progression. CT is routinely used for post-RFA follow-up. PET and PET/CT have emerged as auxiliary follow-up techniques. CT with nodule densitometry may be used to supplement standard CT. Post-RFA follow-up was divided into three phases: early (immediately after to 1 week after RFA), intermediate (>1 week to 2 months), and late (>2 months). CT and PET imaging features suggestive of residual or recurrent disease include (a) increasing contrast material uptake in the ablation zone (>180 seconds on dynamic images), nodular enhancement measuring more than 10 mm, any central enhancement greater than 15 HU, and enhancement greater than baseline anytime after ablation; (b) growth of the RFA zone after 3 months (compared with baseline) and definitely after 6 months, peripheral nodular growth and change from ground-glass opacity to solid opacity, regional or distant lymph node enlargement, and new intrathoracic or extrathoracic disease; and (c) increased metabolic activity beyond 2 months, residual activity centrally or at the ablated tumor, and development of nodular activity.

Contrast-enhanced breast MRI is now widely used in the United States. The information gained from this survey should provide reasonable approaches for the development of professional practice guidelines.

Nonsurgical management of early primary lung cancer has grown tremendously in recent years, and today, available options extend far beyond that of conventional radiation therapy (CRT) to include minimally invasive image-guided delivery of thermal energies, specifically radiofrequency ablation, microwave ablation, and cryoablation, and more conformal stereotactic body radiation therapy. Because the tumor is never resected with these nonoperative interventions, histopathological evaluation of tumor margins for the presence of residual tumor is impossible, and as such, tumor response after each of these therapies is largely based on imaging. To date, computerized tomography and computerized tomography-positron emission tomography remain the most readily available modalities for assessment of therapeutic efficacy, and to this end as detailed within this article, strict imaging survey and familiarity with the expected imaging characteristics of the treated tumor will aid in recognition of unexpected findings, specifically those of incomplete therapy and/or tumor recurrence.

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Salvage of a failed arteriovenous access with occlusion of the venous outflow and no alternative for a secondary arteriovenous fistula that would provide for immediate dialysis is a difficult problem for which there is no ideal solution. The present report is such a patient. The patient had a radial-cephalic fistula represented by only a very short segment, inadequate for effective dialysis. Salvage was accomplished using the sharp needle revascularization technique in order to avoid a prolonged period of central venous catheter use.