Screening for cerebellopontine angle tumors: is a CISS sufficient?

This study attempted to evaluate the reliability of ultra-thin T₂-weighted imaging with a constructive interference in steady state (CISS) sequence as a screening method for tumors in the cerebellopontine angle. A retrospective study of 200 CISS examinations was made by five investigators. The examinations were inspected on plain film supported by clinical information. The interobserver agreement in the detection of lesions was analyzed. Fourteen cases (50% of the contrast-enhancing lesions) were rated pathological by all five readers. One case of subarachnoid lymphoma infiltration was overlooked by all five readers. Overall, six pathological lesions (median = 6, range 1–9) were not identified. The interobserver agreement for all pathological lesions was moderate (=0.53; 95% CI, 0.43–0.62). The mean sensitivity was 77.8% (range 72.0–96.3%), and the mean specificity was 97.6% (range 94.8–100%). The median sensitivity for pathological lesions concerning only patients with acute sensorineural hearing loss (n=148, patients with 20 contrast-enhancing cases) was 86.6% (range 80–100%), and median specificity was 95.2% (range 84.4–96.9%) with a moderate interobserver agreement (=0.55; 95% CI, 0.44–0.66). In our opinion the CISS sequence is a valuable addition to the examination of the cerebellopontine angle but lacks sufficient reliability for the detection of tumors of small size or of tumors adjacent to brain parenchyma or the temporal bone.     

Emergency medicine: the growth of training programs and residency positions 1971–2001

Purpose: Over the past 30 years and especially in the last decade, emergency medicine has grown rapidly. The purpose of this study is to review the diffusion and distribution of emergency residencies in the United States. Methods: Data on spatial distribution and residency numbers were obtained from the AMA Annual Directory of Graduate Medical Education. Results: The growth of emergency medicine has been substantial, encompassing 121 programs in 33 states. Currently, nearly 3,600 residents are in training, nearly double the number of trainees 10 years ago. Conclusion: The rapid growth of the pool of emergency medicine physicians is now and will be increasingly a force to reckon with in the allocation of responsibility for performance and interpretation of emergency imaging studies.     

Morphometric scores for renal tumors: What does the radiologist need to know?

Numerous therapeutic options are possible in the treatment of renal carcinomas including radical nephrectomy, partial nephrectomy, cryoablation, radiofrequency, active follow-up and among surgical treatments, different approaches may be used such as laparotomy, laparoscopy, robotic-assisted intervention. The choice between these different procedures is partially based on the anatomic conditions of the tumors. Different anatomic scores determined from cross-sectional imaging have been built to predict the complexity of the surgical procedure. The goals of this article are to review the relevant morphologic pattern for management of patients with renal tumors, to know how to calculate these different scores and to understand the clinical applications of these scores.     

Radiological findings in Birt-Hogg-Dubé syndrome: a rare differential for pulmonary cysts and renal tumors

Birt-Hogg-Dubé syndrome is a rare disorder characterized by cutaneous hair follicle tumors, pulmonary cysts, and renal tumors. We report a case of a 63-year-old male patient with this syndrome. The radiological findings seen with this syndrome are described. Radiologists should be aware of and able to recognize this syndrome.     

Molecular and cellular effects of Auger emitters: 2008–2011

Abstract

Purpose: To review recent Auger emitter research with an emphasis on a review of findings on targeting and accumulation of Auger emitters in tumor cells.

Conclusion: Significant progress can be reported for targeting methods and improvements in methods to accumulate Auger emitters in the target cells, as well as advances in dose calculations. These studies further our understanding of how Auger emitters induce cell death at a cellular and molecular level, supporting the targeted radiomedical applications of Auger emitters.     

Supply and demand for radiographers in Lithuania: A prognosis for 2012–2030

Background

This is the first ever study on the planning of the supply and demand for radiographers in Lithuania. The aim of this study was to analyze the supply and demand for radiographers in the labor market with respect to their number, structure, and services, and to provide a prognosis for the period of 2012–2030.

Materials and methods

Supply was calculated using two scenarios with differing duration of studies, annual student drop-out rates, rates of failure to start working, the annual number of new entrants into the labor market, and emigration rates. Annual mortality rates, the number of first-year students, and retirement rates were evaluated equally in both scenarios.Two projections of the demand for radiographers, based on the population's differing (by age and gender), need for outpatient radiology services, computed tomography, and magnetic resonance scans. Subsequently, the supply and demand scenarios were compared.

Results

Evaluation of the perspective supply and demand scenarios – which are the most probable – revealed a gap forming during the analyzed period, the predicted specialist shortage will reach 0.13 full-time equivalents per 10,000 population, and in 2030—0.37 full-time equivalents per 10,000 population.

Conclusions

Considering the changes in education of radiographers, the socio-demographic characteristics of the staff, and the increasing need for radiographers’ services, the supply of radiographers during the next two decades will be insufficient. To meet the forecasted demand for radiographers in the perspective scenario, the number of students choosing this specialty from 2013 on should increase by up to 30%.     

Availability of both [177Lu]Lu-DOTA-TATE and [90Y]Y-DOTATATE as PRRT agents for neuroendocrine tumors: can we evolve a rational sequential duo-PRRT protocol for large volume resistant tumors?

European Journal of Nuclear Medicine and Molecular Imaging -     

Early detection of colorectal tumors: CT or MRI?

Cancer screening is currently offered for the organs breast, prostate, cervix and colorectum. With progressing technique in computerized tomography (CT) and magnetic resonance imaging (MRI) the colorectum can be increasingly better assessed. Because in CT and MRI also other organs are imaged with the colorectum, a colorectal screening automatically becomes a multiorgan screening. CT and MRI protocols designed for early detection of colorectal tumors are presented and discussed with regard to monoorganscreening (in CT: low dose, no i.v. contrast) and multiorganscreening (in CT: diagnostic dose for neighboured organs with i.v. contrast). More information under http://www.multiorganscreening.org.     

Neuroimaging diagnosis of pineal region tumors—quest for pathognomonic finding of germinoma

Introduction

Our study aimed to elucidate the imaging features for the differentiation of pineal germinoma and other pineal region tumors.

Methods

Image data sets of computed tomographic (CT) scan and magnetic resonance imaging (MRI) data of 93 pineal region tumors including 33 germinomas, 30 nongerminomatous germ cell tumors (NGGCTs), 20 pineal parenchymal tumors (PPTs), and 10 miscellaneous tumors of pineal region were reviewed. Imaging features on CT and MRI were qualitatively assessed by three readers. To know the reasons for morphological differences between germinomas and NGGCTs, histological investigation was done.

Results

Localized calcification was seen in more than 70 % of germ cells tumors (GCTs: germinomas and NGGCTs) while it was scattered in more than half of PPTs. Cystic components in tumors were most frequent in NGGCTs (62 %). Multiplicity of lesion was restricted to GCTs: 39.4 % in germinoma and 10.0 % in NGGCTs. Thick peritumoral edema was more frequent in germinoma than in NGGCT: 40.6 vs. 14.8 % (p?=?0.0433, Fisher’s test). Bithalamic extension of tumor was seen in 78.8 % of germinomas. It was significantly rare in other groups of tumors (p?<?0.0001, Fisher’s test). The relative collagen amount per unit area was significantly lower in germinoma than in NGGCTs.

Conclusion

By paying attention to characteristic features as bithalamic extension, thick peritumoral edema, calcification pattern, multiplicity, and their combination, the preoperative differential diagnosis of pineal germinoma will become more accurate.     

MR Imaging–Guided Percutaneous Cryotherapy for Lung Tumors: Initial Experience

PurposeTo evaluate prospectively the initial clinical experience of magnetic resonance (MR) imaging–guided percutaneous cryotherapy of lung tumors.Materials and MethodsMR imaging–guided percutaneous cryotherapy was performed in 21 patients with biopsy-proven lung tumors (12 men, 9 women; age range, 39–79 y). Follow-up consisted of contrast-enhanced chest computed tomography (CT) scan performed at 3-month intervals to assess tumor control; CT scanning was carried out for 12 months or until death.ResultsCryotherapy procedures were successfully completed in all 21 patients. Pneumothorax occurred in 7 (33.3%) of 21 patients. Chest tube placement was required in one (4.8%) case. Hemoptysis was exhibited by 11 (52.4%) patients, and pleural effusion occurred in 6 (28.6%) patients. Other complications were observed in 14 (66.7%) patients. The mean follow-up period was 10.5 months (range, 9–12 mo) in patients who died. At month 12 of follow-up, 7 (33.3%) patients had a complete response to therapy, and 10 (47.6%) patients showed a partial response. In addition, two patients had stable disease, and two patients developed progressive disease; one patient developed a tumor in the liver, and the other developed a tumor in the brain. The 1-year local control rate was 81%, and 1-year survival rate was 90.5%.ConclusionsMR imaging–guided percutaneous cryotherapy appears feasible, effective, and minimally invasive for lung tumors.     

Repeat radiofrequency ablation for local progression of lung tumors: does it have a role in local tumor control?

PURPOSE: To retrospectively evaluate the role of repeat radiofrequency (RF) ablation for local progression of lung tumors in local tumor control. MATERIALS AND METHODS: From June 2001 to February 2007, the authors treated 797 lung tumors (primary lung cancer, n=66; metastatic lung neoplasm, n=731; mean tumor size, 1.7 cm) in 295 patients with RF ablation. After RF ablation, patients were followed-up with contrast-enhanced chest computed tomography at 1, 3, 6, 9, and 12 months and thereafter at 6-month intervals. Local progression was observed in 117 of the 797 lung tumors. Fifty repeat RF ablation sessions were performed for 56 tumors (primary lung cancer, n=9; metastatic lung neoplasm, n=47; mean tumor size, 2.7 cm) in 46 patients (33 men, 13 women; mean age, 59.6 years). Repeat RF ablation was not performed for the remaining 61 locally progressing tumors because it was not presumed to provide survival benefit. For all 797 tumors, the overall primary and secondary technique effectiveness rates (TERs) after the first RF ablation were compared with each other. To determine the risk factors for local control with repeat RF ablation, multiple variables were analyzed. Next, local control with repeat RF ablation was evaluated for tumors with and tumors without risk factors. RESULTS: The overall secondary TERs were significantly higher than the overall primary TERs (P<.00001). Tumor size of at least 2 cm at the first RF ablation (P=.045) and contact with bronchi (P=.045) or vessels (P=.048) were risk factors for local control with repeat RF ablation. The secondary TERs after the first RF ablation were 94% at 1 year, 68% at 2 years, and 55% at 3 years for tumors without risk factors and 60% at 1 year and 40% at 2 years for tumors with at least one risk factor. Among the 50 repeat RF ablation sessions, pneumothorax occurred in 13 sessions (26%), one of which necessitated chest tube placement; pleural effusion occurred in nine sessions (18%), all of which resolved spontaneously. Thermal injury of the brachial plexus occurred after one session. CONCLUSIONS: Repeat RF ablation improved the overall local control outcomes. In particular, it offered an opportunity to salvage tumors that had no risk factors but nevertheless progressed locally after the first RF ablation. Conversely, tumors with risk factors were not controlled sufficiently even after repeating the procedure.     

Percutaneous ablation of renal tumors: radiofrequency ablation or cryoablation?

Percutaneous ablation of renal tumors, including radiofrequency ablation and cryoablation, are increasingly being used for small tumors as an alternative to surgery for poor surgical candidates. Compared to radiofrequency ablation, cryoablation has several advantages: improved volume control and preservation of adjacent structures due to the excellent depiction of the ice ball on CT and MRI; better protection of the collecting system for central tumor with reduced risk of postprocedural urinary fistula. The main pitfall of cryoablation is the higher cost. Therefore, cryoablation should be reserved for the treatment of complex tumors. In this article, we will review the different steps of percutaneous renal tumor ablation procedures including patient selection, technical considerations, and follow-up imaging.     

ACR–ABS–ACNM–ASTRO–SIR–SNMMI practice parameter for selective internal radiation therapy or radioembolization for treatment of liver malignancies

PurposeThe American College of Radiology (ACR), American Brachytherapy Society (ABS), American College of Nuclear Medicine (ACNM), American Society for Radiation Oncology (ASTRO), Society of Interventional Radiology (SIR), and Society of Nuclear Medicine and Molecular Imaging (SNMMI) have jointly developed a practice parameter on selective internal radiation therapy (SIRT) or radioembolization for treatment of liver malignancies. Radioembolization is the embolization of the hepatic arterial supply of hepatic primary tumors or metastases with a microsphere yttrium-90 brachytherapy device.Materials and MethodsThe ACR -ABS -ACNM -ASTRO -SIR -SNMMI practice parameter for SIRT or radioembolization for treatment of liver malignancies was revised in accordance with the process described on the ACR website (https://www.acr.org/ClinicalResources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters—Interventional and Cardiovascular Radiology of the ACR Commission on Interventional and Cardiovascular, Committee on Practice Parameters and Technical Standards—Nuclear Medicine and Molecular Imaging of the ACR Commission on Nuclear Medicine and Molecular Imaging and the Committee on Practice Parameters—Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with ABS, ACNM, ASTRO, SIR, and SNMMI.ResultsThis practice parameter is developed to serve as a tool in the appropriate application of radioembolization in the care of patients with conditions where indicated. It addresses clinical implementation of radioembolization including personnel qualifications, quality assurance standards, indications, and suggested documentation.ConclusionsThis practice parameter is a tool to guide clinical use of radioembolization. It focuses on the best practices and principles to consider when using radioemboliozation effectively. The clinical benefit and medical necessity of the treatment should be tailored to each individual patient.