Magnetic Resonance Imaging–guided Volumetric Ablation of Symptomatic Leiomyomata: Correlation of Imaging with Histology

PurposeTo describe the preliminary safety and accuracy of a magnetic resonance (MR) imaging–guided high-intensity–focused ultrasound (HIFU) system employing new technical developments, including ablation control via volumetric thermal feedback, for the treatment of uterine leiomyomata with histopathologic correlation.Materials and MethodsIn this phase I clinical trial, 11 women underwent MR-guided HIFU ablation (Sonalleve 1.5T; Philips Medical Systems, Vantaa, Finland), followed by hysterectomy within 30 days. Adverse events, imaging findings, and pathologic confirmation of ablation were assessed. The relationship between MR imaging findings, thermal dose estimates, and pathology and HIFU spatial accuracy were assessed using Bland-Altman analyses and intraclass correlations.ResultsThere were 12 leiomyomata treated. No serious adverse events were observed. Two subjects decided against having hysterectomy and withdrew from the study before surgery. Of 11 women, 9 underwent hysterectomy; all leiomyomata demonstrated treatment in the expected location. A mean ablation volume of 6.92 cm³ ± 10.7 was observed at histopathologic examination. No significant differences between MR imaging nonperfused volumes, thermal dose estimates, and histopathology ablation volumes were observed (P > .05). Mean misregistration values perpendicular to the ultrasound beam axis were 0.8 mm ± 1.2 in feet-head direction and 0.1 mm ± 1.0 in and left-right direction and ?0.7 mm ± 3.1 along the axis.ConclusionsSafe, accurate ablation of uterine leiomyomata was achieved with an MR-guided HIFU system with novel treatment monitoring capabilities, including ablation control via volumetric thermal feedback.     

Imaging of the spine: Where do we stand?

The number of patients presenting with spine-related problems has globally increased, with an enormous growing demand for the use of medical imaging to address this problem. The last three decades witnessed great leaps for diagnostic imaging modalities, including those exploited for imaging the spine. These developments improved our diagnostic capabilities in different spinal pathologies, especially with multi-detector computed tomography and magnetic resonance imaging, via both hardware and software improvisations. Nowadays, imaging may depict subtle spinal instability caused by various osseous and ligamentous failures, and could elucidate dynamic instabilities. Consequently, recent diagnostic modalities can discern clinically relevant spinal canal stenosis. Likewise, improvement in diagnostic imaging capabilities revolutionized our understanding of spinal degenerative diseases via quantitative biomarkers rather than mere subjective perspectives. Furthermore, prognostication of spinal cord injury has become feasible, and this is expected to be translated into better effective patient tailoring to management plans with better clinical outcomes. Meanwhile, our confidence in diagnosing spinal infections and assessing the different spinal instrumentation has greatly improved over the past few last decades. Overall, revolutions in diagnostic imaging over the past few decades have upgraded spinal imaging from simple subjective and qualitative indices into a more sophisticated yet precise era of objective metrics via deploying quantitative imaging biomarkers.     

Imaging of carotid artery disease: from luminology to function?

There have been tremendous advances in our ability to image atheromatous disease, particularly in the carotid artery, which is accessible and large enough to image. The repertoire of methodology available is growing, giving anatomical information on luminal narrowing which is approaching the level at which conventional carotid angiography will become very uncommon as CT and contrast-enhanced MR angiographic techniques become the norm. More exciting is the tentative ability to perform functional plaque imaging addressing enhancement patterns and macrophage activity using MR or positron-emission tomography techniques. These techniques, once rigorously evaluated, may, in addition to complex mathematical modelling of plaque, eventually allow us to assess true plaque risk. Time will best judge whether we will be able to move from the use of simple luminology to assessment of plaque function.The online version of the original article can be found at     

Imaging of carotid artery disease: from luminology to function?

There have been tremendous advances in our ability to image atheromatous disease, particularly in the carotid artery, which is accessible and large enough to image. The repertoire of methodology available is growing, giving anatomical information on luminal narrowing which is approaching the level at which conventional carotid angiography will become very uncommon as CT and contrast-enhanced MR angiographic techniques become the norm. More exciting is the tentative ability to perform functional plaque imaging addressing enhancement patterns and macrophage activity using MR or positron-emission tomography techniques. These techniques, once rigorously evaluated, may, in addition to complex mathematical modelling of plaque, eventually allow us to assess true plaque risk. Time will best judge whether we will be able to move from the use of simple luminology to assessment of plaque function.An addendum to this article can be found at     

Imaging of prostate cancer local recurrences: why and how?

Objective  

Because prostate cancer local recurrences can be efficiently treated by salvage therapies, it becomes critical to detect them early.     

Musculoskeletal Imaging with Computed Tomography and Magnetic Resonance Imaging: When is Computed Tomography the Study of Choice?

Indications for computed tomography (CT) of the musculoskeletal system, especially with the advent of 16-slice multidetector CT (MDCT), are numerous. In addition to the evaluation of the trauma patient where CT is essential when imaging complex skeletal injuries, MDCT is particularly useful in patients who have had prior surgery. In postoperative cases, metal artifact typically prohibits magnetic resonance imaging evaluation, but volume-rendering of a MDCT axial database virtually eliminates streak artifact associated with hardware. For the evaluation of masses, CT provides the ability to detect and characterize calcification, cortical disruption, and periosteal reaction. In this article, these and other indications for performance of CT of the musculoskeletal system will be discussed.     

Imaging of penile traumas—therapeutic implications

Injury to the penis may result from penetrating or nonpenetrating trauma. Nonpenetrating injury to the erect penis can produce albugineal tear, intracavernous hematoma or extraalbugineal hematoma from rupture of the dorsal vessels. Nonpenetrating injury to the flaccid penis usually follows blunt perineal traumas producing extratunical or cavernosal haematomas, or cavernosal artery tear followed by high flow priapism. Differential diagnosis between albugineal tear and other penile injuries must be obtained as soon as possible, since early surgical repair of albugineal tear reduces significantly the rate of postraumatic curvature and fibrosis. Ultrasonography (US) is able to detect the exact site of the tear in most patients as an interruption of the thin echogenic line of the tunica albuginea. Other imaging techniques are rarely required in the clinical practice. Color Doppler US is the imaging modality of choice to evaluate patients with high flow priapism. Focal or diffuse cavernosal fibrosis can be identified with US as echogenic areas in the cavernosal bodies. Postraumatic erectile dysfunction can result from fibrotic changes, nerve and vascular impairment or both. Doppler evaluation of penile vasculature is required in young patients with postraumatic impotence before surgical revascularization procedures.     

Imaging genetics of brain longevity and mental wellness: the next frontier?

The advent of new "omics" technologies (genomics, proteomics, and metabolomics) has ushered in a new era of biomedical discovery that is already affecting every field of medicine. With the rapid growth of the older population worldwide, there is great interest in applying these technologies not only to diagnose and prevent disease, but also to enhance brain longevity and mental wellness. Nearly two-thirds of the approximately 30,000 genes in the human genome are related to brain function, and up to half of the variance in age-related changes in cognition, brain volume, and neuronal function appears to be genetically determined. Selected examples will be used to illustrate how neuroimaging is being employed to study the effects of genes and how neurogenetics may affect future radiology research and practice.     

Imaging of the small bowel: Crohn’s disease in paediatric patients

In more than 20% of all patients, the Crohn’s disease presents before the age of 18years. The diagnosis and management of Crohn’s disease in children has changed dramatically over the last decade, mainly due to increased awareness, availability of newer diagnostic modalities such as magnetic resonance imaging (MRI) and newer, more powerful treatments such as biologics. Imaging of the small bowel is needed for diagnosis, management, follow-up and also evaluation of the disease in terms of location, extent, activity and complications. We review all the methods (barium examinations, ultrasonography, computed tomography, MR, and computed tomography- positron emission tomography) commonly used for imaging the small bowel in paediatric patients with Crohn’s disease analyzing the advantages and disadvantages of each modality, with particular emphasis on MR imaging.     

Percutaneous MR Imaging–Guided Cryoablation of Small Renal Masses in a 3-T Closed-Bore MR Imaging Environment: Initial Experience

Purpose

To assess the feasibility of percutaneous magnetic resonance (MR) imaging–guided cryoablation of small renal masses (SRMs) in a 3-T environment and to evaluate intraprocedural imaging, procedural safety, and initial outcomes.

Imaging strategies in the management of oesophageal cancer: what’s the role of MRI?

Objectives

To outline the current role and future potential of magnetic resonance imaging (MRI) in the management of oesophageal cancer regarding T-staging, N-staging, tumour delineation for radiotherapy (RT) and treatment response assessment.

Methods

PubMed, Embase and the Cochrane library were searched identifying all articles related to the use of MRI in oesophageal cancer. Data regarding the value of MRI in the areas of interest were extracted in order to calculate sensitivity, specificity, predictive values and accuracy for group-related outcome measures.

Results

Although historically poor, recent improvements in MRI protocols and techniques have resulted in better imaging quality and the valuable addition of functional information. In recent studies, similar or even better results have been achieved using optimised MRI compared with other imaging strategies for T- and N-staging. No studies clearly report on the role of MRI in oesophageal tumour delineation and real-time guidance for RT so far. Recent pilot studies showed that functional MRI might be capable of predicting pathological response to treatment and patient prognosis.

Conclusions

In the near future MRI has the potential to bring improvement in staging, tumour delineation and real-time guidance for RT and assessment of treatment response, thereby complementing the limitations of currently used imaging strategies.

Key Points

? MRI’s role in oesophageal cancer has been somewhat limited to date. ? However MRI’s ability to depict oesophageal cancer is continuously improving. ? Optimising TN-staging, radiotherapy planning and response assessment ultimately improves individualised cancer care. ? MRI potentially complements the limitations of other imaging strategies regarding these points.