Search

The purpose of this article was to review the basic properties of available gadolinium-based magnetic resonance contrast agents, discuss their fundamental differences, and explore common and evolving applications of gadolinium-based magnetic resonance contrast throughout the body excluding the central nervous system. A more specific aim of this article was to explore novel uses of these gadolinium-based contrast agents and applications where a particular agent has been demonstrated to behave differently or be better suited for certain applications than the other contrast agents in this class.

e15667 Background: iHCC is an aggressive disease with poorly characterized treatment outcomes. We sought to describe clinical and radiographic features of iHCC, describe overall survival (OS), and compare outcomes of sorafenib (SOR) use with a cohort of non-infiltrative hepatocellular carcinoma (niHCC) patients. Methods: Radiology reports from the University of Washington with an Li-RADS (LR) assignment, 2013-2017, were reviewed (5037 reports, 1954 patients (pts)) for terms indicative of iHCC. Results: : 102 cases were identified, with 43% arising from known niHCC. iHCC size is difficult to measure but when reported, median was 8cm (interquartile range 5-10cm). Other radiographic features: vascular invasion 72%, R lobe only 62%. Clinical data were obtained via medical record review. The cohort was primarily male (83%), White (65%), age > 55 (88%), HCV (74.5%), heavy alcohol use (67%). At diagnosis: BCLC stage C (76%), ALBI grade 2 (62%) and 3 (21%). Median OS after diagnosis was 5.7 months (m). 38 (37%) pts were too ill to receive therapy. OS for de novo iHCC and for iHCC arising from niHCC did not differ (7.5m vs 5.1m, p = NS). All niHCC pts who received SOR in any line of therapy were identified among pts with a LR 5 lesion in at least one of the aforementioned radiology reports, 2013-2017. Pts who received SOR on trial and/or combined with another agent were excluded. Clinical data for the 83 niHCC pts were abstracted and compared to the 25 iHCC pts who received SOR, any line of therapy. Based on χ2 analyses, the 2 groups did not differ by age, sex, race, BCLC stage at SOR initiation, ECOG status at SOR initiation, HCC etiology, ALBI grade at SOR initiation, or previous locoregional therapy. OS after initiation of SOR was 14.1m for niHCC, 10.5m for iHCC, p = NS. PFS after SOR was 3.7m for niHCC, 7m for iHCC, p = NS. AFP at the time of SOR initiation was higher in iHCC than niHCC (median 1331 vs 48, respectively, p = 0.004), with median %AFP change after 30 days -13% in iHCC and +6% in niHCC, p = NS. Decrease in AFP after 30 days of therapy was associated with improved OS among niHCC (21m versus 7m, p = 0.001) but not among iHCC pts (p = NS). Conclusions: iHCC is a poorly understood subset of HCC with underlying biology not well defined. Compared to niHCC, clinical outcomes with sorafenib do not appear to differ in this cohort. Future characterization of outcomes with Y-90 and immune checkpoint inhibitors is warranted.

e15668 Background: We sought to identify clinical predictors of radiographic progression of a Li-RADS (LR) 3 lesion (i.e. indeterminate for hepatocellular carcinoma (HCC)) to a LR 5 lesion (i.e. definitely HCC) among patients (pts) at high risk of HCC. Methods: Radiology reports from the University of Washington with an LR assignment, 2013-2017, were reviewed (5037 reports, 1954 patients(pts)). Pts with an LR 3 lesion, a follow-up scan within 1 year of date of LR 3 lesion detection, and radiographic evidence of cirrhosis OR a diagnosis of chronic HBV were included in the analysis. Results: Of the 167 pts, 38 (23%) progressed to LR 5 status, 10 progressed to LR 4, and 12 were downgraded to LR 1-2. The remaining 64% were unchanged at LR 3. Radiographic data including year of LR 3 detection (2013-2014 47%) and LR 3 imaging modality (CT 50.3%, MR 49.7%) were obtained. Clinical data were abstracted from medical record review, including sex (65% male), age (80% < 65), race (66% White), cirrhosis etiology (45% HCV, 27% EtOH, 22% NASH, 8% HBV), HCV genotype, HCV treatment status, AFP, and ALBI score (G2 54%, G3 16%, unk 15%). Variables of interest (age, sex, race, cirrhosis etiology, AFP, ALBI score, year of LR 3 detection, imaging modality) were included in proportional hazards modeling with the underlying time metric defined as time from LR 3 detection to date of LR 5 detection or date of last scan up to one year after LR 3 identification. Backwards elimination modeling was performed until remaining variables were associated with the outcome at a level of significance of p < 0.05 (Table 1). Among those with chronic HCV, risk of progression to LR 5 did not differ by HCV genotype (1a, 1b, 2, 3, other, unknown) or sustained viral response status at the time of LR 3 detection. Table 1: Multivariate hazard ratios (HR) and 95% confidence interval (CI) estimates. Conclusions: Chronic HCV, older age at LR 3 detection, earlier year of LR 3 detection, and male sex appear independently associated with risk of progression to LR 5. The identification of clinical factors associated with LR 3 progression may allow for the development of risk modeling tools to assist clinicians in determining frequency of follow-up imaging and optimal timing of intervention.[Table: see text]

Purpose Accurate characterization of contrast reagent (CR) longitudinal relaxivity in whole blood is required to predict arterial signal intensity in contrast-enhanced MR angiography (CE-MRA). This study measured the longitudinal relaxation rate constants (R1) over a concentration range for non-protein-binding and protein-binding CRs in ex vivo whole blood and plasma at 1.5 and 3.0 Tesla (T) under physiologic arterial conditions. Methods Relaxivities of gadoteridol, gadobutrol, gadobenate, and gadofosveset were measured for [CR] from 0 to 18 mM [mmol(CR)/L(blood)]: the latter being the upper limit of what may be expected in CE-MRA. Results In plasma, the 1H2O R1 [CR]-dependence was nonlinear for gadobenate and gadofosveset secondary to CR interactions with the serum macromolecule albumin, and was well described by an analytical expression for effective 1:1 binding stoichiometry. In whole blood, the 1H2O R1 [CR]-dependence was markedly non-linear for all CRs, and was well-predicted by an expression for equilibrium exchange of water molecules between plasma and intracellular spaces using a priori parameter values only. Conclusion In whole blood, 1H2O R1 exhibits a nonlinear relationship with [CR] over 0 to 18 mM CR. The nonlinearity is well described by exchange of water between erythrocyte and plasma compartments, and is particularly evident for high relaxivity CRs. Magn Reson Med 72:1746–1754, 2014. © 2013 Wiley Periodicals, Inc.

Mesenchymal liver tumors are rarely encountered in clinical practice. We review the spectrum of mesenchymal liver tumors with radiologic-pathologic correlation. There is an overlap of cross-sectional imaging findings of mesenchymal liver tumors with that of the more common malignant epithelial tumors. Familiarity with the radiologic findings and its pathologic basis would help radiologists to include these uncommon liver tumors in their differential diagnosis.

Diffusion-weighted magnetic resonance imaging is based on the Brownian motion of water and enables quantification of the apparent diffusion coefficient throughout the body. This article discusses the principles of diffusion-weighted magnetic resonance imaging, as well as the possible applications and limitations as they apply to liver imaging. This will introduce the readers to this novel magnetic resonance imaging tool, which has a promising future.

We are in the midst of an evolving educational revolution. Use of digital devices such as smart phones and tablet computers is rapidly increasing among radiologists who now regularly use them for medical, technical, and administrative tasks. These electronic tools provide a wide array of new tools to the radiologists allowing for faster, more simplified, and widespread distribution of educational material. The utility, future potential, and limitations of some these powerful tools are discussed in this article.

To study the role of tympanoplasty alone and tympanoplasty done along with cortical mastoidectomy in CSOM in term of graft uptake, improvement of hearing and removal of disease. This is retrospective study of patient at tertiary referral centre, conducted in between October 2015 and October 2016, study was done on 40 patients of either sex in the age group 20-50 years. Tympanoplasty alone was done in 20 cases and tympanoplasty along with cortical mastoidectomy was done in rest 20 cases. Patient were reviewed post operatively on 2, 4, 8 and 16 weeks to inspect post operative graft uptake and PTA was done at fourth month to evaluate hearing improvement. Hearing improvement was compared in both the groups in tympanoplasty group was 9.41 and in tympanoplasty combined with cortical mastoidectomy was 12.05. Graft uptake was 80% in tympanoplasty group and 95% in tympanoplasty combined with cortical mastoidectomy. Recurrence of discharge was seen in 4 cases of tympanoplasty. Though tympanoplasty combined with cortical mastoidectomy is better in hearing improvement, graft uptake and clinical improvement but the difference in 2 groups is statistically insignificant. Results of tympanoplasty alone and tympanoplasty along with cortical mastoidectomy in terms of hearing gain and graft uptake were statistically insignificant.

Purpose Urgent appendectomy has long been the standard of care for acute appendicitis. Six randomized trials have demonstrated that antibiotics can safely treat appendicitis, but approximately 1 in 4 of these patients eventually requires appendectomy. Overall treatment success may be limited by complex disease including perforation. Patients׳ success on antibiotic therapy may depend on preoperative identification of complex disease on imaging. However, the effectiveness of computed tomography (CT) in differentiating complex disease including perforated from nonperforated appendicitis remains to be determined. The purpose of this study was to assess the preoperative diagnostic accuracy of CT in determining appendiceal perforation in patients operated for acute appendicitis. Methods We performed a retrospective review of pathology and radiology reports from consecutive patients who presented to the emergency department with suspicion for acute appendicitis between January 2012 and May 2015. CT scans were re-reviewed by abdominal imaging fellowship-trained radiologists using standardized criteria, and the radiologists were blinded to pathology and surgical findings. Radiologists specifically noted presence or absence of periappendiceal gas, abscess, appendicolith, fat stranding, and bowel wall thickening. The overall radiologic impression as well as these specific imaging findings was compared to results of pathology and operative reports. Pathology reports were considered the standard for diagnostic accuracy. Results Eighty-nine patients (65% male, average age of 34 years) presenting with right lower quadrant pain underwent CT imaging and prompt appendectomy. Final pathology reported perforation in 48% ( n = 43) of cases. Radiologic diagnosis of perforation was reported in 9% ( n = 8), correctly identifying perforation in 37.5% ( n = 3), and incorrectly reporting perforation in 62.5% of nonperforated cases per pathology. Radiology missed 93% ( n = 40) of perforations postoperatively diagnosed by pathology. There was no secondary finding (fat stranding, diameter >13mm, abscess, cecal wall thickening, periappendiceal gas, simple fluid collection, appendicolith, and phlegmon) with a clinically reliable sensitivity or specificity to predict perforated appendicitis. Surgeon׳s report of perforation was consistent with the pathology report of perforation in only 28% of cases. Conclusions The usefulness of a CT for determining perforation in acute appendicitis is limited, and methods to improve precision in identifying patients with complicated appendicitis should be explored as this may help for improving risk prediction for failure of treatment with antibiotic therapy and help guide patients and providers in shared decision-making for treatment options.

OBJECTIVE. Although some research and publication practices are clearly unethical, including fraud and plagiarism, other areas of research and publication, such as informed consent and conflicts of interest, fall into grayer areas. CONCLUSION. The purposes of this article are, therefore, to review a variety of relevant ethical issues in radiology-related journalism, peer review, and research; to review the radiology literature to date that has addressed these issues; and to present position statements and potential solutions to these problems.

Objective The purpose of our study was to determine the current practice patterns of U.S. radiologists in imaging pregnant or potentially pregnant patients with acute abdominal and pelvic conditions. Materials and methods After obtaining an Institutional Review Board waiver, all members of the Association of University Radiologists, the Association of Program Directors in Radiology, and the Society of Radiologists in Ultrasound were invited via e-mail to take a 23-question online survey on radiology practices and clinical scenarios about acute abdominal and pelvic imaging of pregnant patients. Results Comparisons were made with previously published surveys. A total of 225 responses were received. Areas of high consensus included pregnancy assessment (97%) and obtaining informed consent (87%) before imaging, having a written policy on imaging pregnant patients (79%), modification of computed tomography (CT) protocols (74%), avoiding gadolinium contrast in magnetic resonance imaging (MRI) (74%), using ultrasound for initial imaging in some scenarios, and using CT in trauma cases after inconclusive ultrasound. Areas of emerging consensus compared to 2007 included the use of serum or urine testing to confirm pregnancy status (59.4%; previously 14%) and the use of MRI in suspected appendicitis after an inconclusive ultrasound (73% in first trimester and 67% in third trimester; previously 46% and 29%, respectively). Areas without clear consensus included policy development, additional modifications to MRI protocols, choice of imaging modality, radiation dose, and the use of contrast agents in some scenarios. Conclusion In conclusion, high or increasing consensus exists in some areas of imaging pregnant patients with acute abdominal and pelvic conditions, but has yet to emerge in other areas.

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.

Hepatocellular carcinoma (HCC) is the second largest cause of cancer mortality in the world, with vascular invasion being one of the most important prognostic factors. HCC with tumor thrombus was traditionally considered to have very limited treatment options. However, multiple promising treatment strategies have emerged in recent years, with diagnostic and interventional radiologists playing a major role in patient management. We provide a comprehensive update on the diagnosis and management of HCC with vascular invasion and the role of the radiologist in this condition.

The placenta has a fundamental role in fetal health and functions as an important bridge to normal fetal development throughout pregnancy. A complete fetal ultrasound (US) survey should include full assessment of the placenta for any possible abnormalities. Placental diseases range from abnormal morphology, size, location, extent, and degree of placentation, to abruption and the presence of rare placental neoplasms of benign or malignant nature. Some of these conditions are associated with other diseases including aneuploidies, and their discovery should alert the radiologist to perform a very thorough fetal US examination. At times, a fetal karyotype may be needed to provide additional information. Timely detection of placental abnormalities can alert the clinician regarding the need to make important management decisions to reduce fetal and maternal morbidity and mortality. Familiarity with the normal and abnormal imaging appearance of the placenta is therefore necessary for the radiologist. Ultrasound with Doppler is the initial imaging modality of choice for placental assessment. Magnetic resonance imaging serves as a problem-solving examination in instances where the US findings are equivocal or where additional information is needed. Computed tomography has a limited role in the evaluation of placental disease because of its relatively limited tissue characterization and in particular because of the resultant direct radiation exposure of the fetus. However, in specific instances, particularly after trauma, computed tomography can provide invaluable information for patient management.

Liver transplant is the treatment of choice for end-stage liver disease. Management of transplant patients requires a multidisciplinary approach, with radiologists playing a key role in identifying complications in both symptomatic and asymptomatic patients. Ultrasonography remains the investigation of choice for the initial evaluation of symptomatic patients. Depending on the clinical situation, further evaluation with CT, MRI, or biopsy may be performed or clinical and imaging surveillance may be continued. This article discusses the various normal and abnormal imaging presentations of liver transplant patients, including various acute and chronic complications, and their management.

Renal transplant complications are categorized as those related to the transplant vasculature, collecting system, perinephric space, renal parenchyma, and miscellaneous complications including posttransplant lymphoproliferative disorder. Many of these renal transplant complications are diagnosed with imaging. Medical complications including rejection, acute tubular necrosis, and drug toxicity also can impair renal function. These medical complications are typically indistinguishable at imaging, and biopsy may be performed to establish a diagnosis. Normal transplant anatomy, imaging techniques, and the appearances of renal transplant complications at ultrasound, computed tomography, and MR imaging are reviewed.

Brief patient encounters can be challenging for a radiologist on a busy service. We often meet patients for the first time (without the benefit of an established patient-physician relationship), break bad news to patients who are often more comfortable discussing difficult and stressful medical results with their primary care providers, and are asked management-related questions immediately following a brief review of complicated studies. Without dedicated clinic time, these encounters are often considered disruptive to the daily workflow. Our goal in this article is to increase awareness of some steps radiologists can take to make brief patient encounters more effectual and thus foster greater patient satisfaction. 2 It helps to start the conversation by explaining that radiologists play a different role than most clinicians and focusing our discussions on imaging findings and not on detailing the management plan. We outline 6 steps and 4 tips based on our personal experience with brief patient interactions that we found especially effectual.

Purpose: To use magnetization tagged magnetic resonance imaging (MRI) (tag-MRI) to quantify cardiac induced liver strain and compare strain of cirrhotic and normal livers. Materials and Methods: Tag-MRI was performed at 1.5T on eight subjects with no history of liver disease and 10 patients with liver cirrhosis. A breath-hold peripheral pulse-gated (PPG) conventional tag-MRI cine sequence was performed with planes to include the left lobe of the liver and the inferior wall of the heart. Commercially available software HARP (Diagnosoft, Palo Alto, CA) was used for image analysis and strain calculation. Three regions-of-interest (ROIs) were selected: segment II of the liver near the heart (A), right liver lobe far from the heart (B), and the left ventricular wall (C). The average and maximal (max) strain were measured in A, B, and C. The maximum strains were used to generate a cardiac-corrected strain gradient: (maxA-maxB)/maxC. Results were compared with Student's t-test (SPSS, Chicago, IL). Results: In subjects with no history of liver disease vs. cirrhotic patients, the average strain was 22% ± 7% vs. 4% ± 3% (P < 0.001), the max strain was 63% ± 15% vs. 17% ± 5% (P < 0.001), and the corrected strain gradient was 0.52 ± 0.16 vs. 0.11% ± 0.08%. Conclusion: There is a significant difference in liver strain measured with tag-MRI between subjects with no history of liver disease and patients with cirrhosis. J. Magn. Reson. Imaging 2012; 36:1490–1495. © 2012 Wiley Periodicals, Inc.

Fat may be noted in a diffuse or focal manner in a variety of nonneoplastic abdominopelvic conditions. The specific signature of macroscopic fat on computed tomography along with the usually characteristic findings of these entities makes the diagnosis of most of these conditions relatively straightforward. In the intestinal tract, the "fat halo sign" usually arises in the context of subacute to chronic bowel wall inflammation. Excess fat in the renal sinus may occur with renal sinus lipomatosis or "replacement lipomatosis of the kidney." Some cases of "pancreatic lipomatosis" may culminate in steatopancreatitis and ultimately neoplastic transformations. "Fibrofatty mesenteric proliferation" is a characteristic feature of Crohn disease. In the setting of the acute abdomen, accurate diagnosis of fat-containing lesions (epiploic appendagitis or omental infarction) from other causes of the acute abdomen is critical. Mesenteric panniculitis is 1 of the causes of the "misty mesentery." Juxtacaval fat deposition is a benign process that has the potential to be confused with more serious conditions. More diffuse fat deposition (abdominal or pelvic lipomatosis) has the potential to become symptomatic by causing mass effect upon the adjacent structures. Fat can also be seen in a variety of postoperative/iatrogenic conditions or abdominal wall/diaphragmatic hernias.

Palpable scrotal mass, acute scrotal pain, and enlarged scrotum are common scenarios in clinical practice. The imaging modality of choice to evaluate scrotal pathology is ultrasound (US). US is key in determining if a palpable abnormality is extratesticular or intratesticular and cystic or solid. US findings help narrow the differential to benign or malignant causes. Extratesticular lesions are more common and usually benign. Rarely, extratesticular solid lesions are malignant but US features are nonspecific. Accurately diagnosing rare benign intratesticular lesions is vital to avoid unnecessary orchiectomy. This article reviews extratesticular and intratesticular lesions presenting as a palpable mass and other conditions commonly seen.

The purpose of this pictorial review is to understand the embryological basis of the development of congenital hepatic vascular shunts and to review the multimodality imaging appearances of congenital and acquired hepatic vascular shunts. Hepatic vascular shunts are commonly seen in imaging. Familiarity with their characteristic appearances is important in order to accurately characterise these shunts and diagnose the underlying disorders.

The purpose of this study was to determine the upper limit of noise for detection of small low-contrast lesions in a liver phantom.A CT liver phantom containing 21 low-contrast, low-attenuation, circular simulated lesions ranging in size from 2.4 to 10 mm was scanned 23 times at different tube current ranges (varying noise index) on a 64-MDCT scanner with automatic tube current modulation. The attenuation of the simulated lesions was 20 HU less than that of the liver-equivalent background. Three radiologists independently reviewed the resultant CT images, which contained either a low-contrast lesion or no lesion and scored certainty of lesion detection using a 4-point Likert scale. Overall performance was evaluated by sensitivity analysis with receiver operator curve and area under the curve (A(z)) computation for ranges of noise index.The reviewers achieved 100% sensitivity with a noise index of 15 or less for lesions measuring 6.3-10.0 mm (A(z) = 0.96). Increasing noise index to the 17-21 range resulted in a minor decrease in sensitivity and overall performance (sensitivity, 92.3%; A(z) = 0.93). A further increase in noise index to the 23-27 range resulted in a moderate decrease in sensitivity (sensitivity, 81.4%; A(z) = 0.77). Beyond the noise index 23-27 range, sensitivity dropped markedly from 81.4% to 39%. Agreement between the three readers in assessing the image sets was moderate.For detection of small low-contrast lesions in the liver phantom model used in this study, the upper limit of noise index may be in the 15-21 range for sensitivity greater than 90%.

Bladder carcinoma is the fourth most common cancer in men and women. Knowledge of imaging options and appearance is necessary for both radiologists and urologists. Transitional cell carcinoma is the most common bladder neoplasm with squamous cell and adenocarcinoma found in less than 10% of cases. Benign lesions are uncommon, but some can be suggested by their imaging appearance. Similarly, malignant lesions often have suggestive appearance and/or location. Cystoscopy allows tissue diagnosis and treatment of superficial lesions. Although magnetic resonance imaging (MRI) and computed tomography (CT) both have limitations in detailing depth of muscle invasion, both have a prominent role helping to define the lesion and in staging. This article illustrates the role of MRI and CT in evaluating bladder masses with a discussion of the newer techniques of MR diffusion-weighted imaging and virtual cystoscopy by CT or MRI. This article reviews the multiple benign and malignant lesions of the bladder so that the reader can appreciate the role of cystoscopy, CT, MRI, diffusion-weighted imaging, and virtual cystoscopy in dealing with these relatively common tumors.

Received September 23, 2010; accepted without revision September 23, 2010. 1Department of Radiology, University of Washington, VA Puget Sound Health Care System, 1660 S Columbian Way, S-114/Radiology, Mail Stop 358280, Seattle, WA 98108. Address correspondence to P. Bhargava (bhargp@u.washington.edu). 2Department of Radiology, University of Washington, Seattle, WA. 3Department of Surgery, University of Washington, Seattle, WA. AJR 2011;196:WS15–WS25 0361–803X/11/1963–S1 © American Roentgen Ray Society Objective Orthotopic liver transplantation is an established treatment for patients with end-stage liver disease or acute liver failure. Complications of liver transplantation include vascular thrombosis and stenosis; arterial pseudoaneurysm; biliary leak, stricture, and obstruction; liver ischemia, infarction, and abscess; recurrent disease; posttransplantation lymphoproliferative disease (PTLD); recurrent tumors; peritransplant fluid collections and hematomas; and splenic infarction. The incidence of graft rejection and other complications experienced in the early years after the surgery has been reduced significantly because of advances in immunosuppression and surgical techniques. The clinical presentation of these complications is often nonspecific, and early detection of these complications on imaging is necessary for appropriate management. Living related liver transplantations are performed commonly, especially in children. Orthotopic liver transplantation is distinct from living related liver transplantation with regard to surgical technique, postoperative anatomy, and some complications. This article reviews the imaging appearances of different surgical techniques as well as the early and late complications of orthotopic liver transplantation.

Received September 23, 2010; accepted without revision September 23, 2010. 1Department of Radiology, University of Washington, VA Puget Sound Health Care System, 1660 S Columbian Way, S-114/Radiology, Mail Stop 358280, Seattle, WA 98108. Address correspondence to P. Bhargava (bhargp@u.washington.edu). 2Department of Radiology, University of Washington, Seattle, WA. 3Department of Surgery, University of Washington, Seattle, WA. AJR 2011; 196:S35–S38 0361–803X/11/1963–S35 © American Roentgen Ray Society ABSTRACT The educational objectives for this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of imaging of orthotopic liver transplant recipients and to improve familiarity with the complications of orthotopic liver transplantation.

Syringoma is a benign adnexal tumor of intraepidermal portion of the eccrine sweat ducts. Eruptive syringoma is a rare clinical variant characterized by small, flesh-colored papules with both follicular and nonfollicular distribution that occur in successive crops on the anterior body surface. We report a case of 35-year-old female with familial eruptive syringoma with predominant acral distribution. We report this case because of the rarity of disorder and acral predominance.

A recurring source of contention between clinicians and radiologists continues to be examination appropriateness when imaging pregnant patients. With the multitude of references on potential radiation risks to the fetus, radiologists tend to be cautious and hesitant about exposing the fetus to radiation. This tendency is often interpreted by referring physicians as intrusion into and delay in the care of their patients. The risk burden of radiation exposure to the fetus has to be carefully weighed against the benefits of obtaining a critical diagnosis quickly and using a single tailored imaging study. In general, there is lower than expected awareness of radiation risks to the fetus from imaging pregnant patients. Modalities that do not use ionizing radiation, such as ultrasonography and magnetic resonance imaging, should be the preferred examinations for evaluating an acute condition in a pregnant patient. However, no examination should be withheld when an important clinical diagnosis is under consideration. Exposure to ionizing radiation may be unavoidable, but there is no evidence to suggest that the risk to the fetus after a single imaging study and an interventional procedure is significant. All efforts should be made to minimize the exposure, with consideration of the risk versus benefit for a given clinical scenario.

Gallbladder cancer is the most common malignant tumor of the biliary tract and often diagnosed incidentally during laparoscopic cholecystectomy for gallbladder disease. This underscores the importance of considering the diagnosis of gallbladder cancer when confronted with atypical findings and understanding cancer management guidelines that may impact patient outcome. Potentially curable early stage gallbladder lesions are often missed during preoperative workup and discovered incidentally during difficult cholecystectomy or afterwards on pathologic diagnosis. We will review current strategies to diagnose early stage disease and discuss clinical management issues to optimize the outcome of patients with gallbladder cancer.

Objectives: To evaluate the frequency of developmental dental anomalies in the Indian population.Methods: This prospective study was conducted over a period of 1 year and comprised both clinical and radiographic examinations in oral medicine and radiology outpatient department. Adult patients were screened for the presence of dental anomalies with appropriate radiographs. A comprehensive clinical examination was performed to detect hyperdontia, talon cusp, fused teeth, gemination, concrescence, hypodontia, dens invaginatus, dens evaginatus, macro- and microdontia and taurodontism. Patients with syndromes were not included in the study.Results: Of the 20,182 patients screened, 350 had dental anomalies. Of these, 57.43% of anomalies occurred in male patients and 42.57% occurred in females. Hyperdontia, root dilaceration, pegshaped laterals (microdontia), and hypodontia were more frequent compared to other dental anomalies of size and shape.Conclusions: Dental anomalies are clinically evident abnormalities. They may be the cause of various dental problems. Careful observation and appropriate investigations are required to diagnose the condition and institute treatment. (Eur J Dent 2010;4:263-269)

Tumoral calcinosis (TC) is a rare entity causing abnormal periarticular calcifications in the affected joint observed in the first two decades of life. It is also known to affect the teeth. Few case reports on TC talk about the dental findings. This article presents the clinical, radiological and histological appearance of dental abnormalities in a 23-year-old female with TC. The differential diagnosis and dental management are discussed.Tumoral calcinosis should be considered in the differential diagnosis of abnormally short roots with complete or partial obliteration of pulp chambers in a young patient.

This paper discusses the effect of varying the shock pulse width on the shock response of small form factor hard disk drives. We develop a new shock simulator for hard disk drives which simulates the structural as well as the air bearing dynamics of the disk drive simultaneously. We observe that the response of the disk to the shock pulse is of critical importance and depends strongly on the pulse width of the shock pulse. We also find that if a suspension bending frequency is close to the first umbrella frequency of the disk, there can be failure of the head–disk interface due to resonance.

Case reports remain an invaluable resource in the literature, and they continue to serve an equally important role in scientific advancement. They record discoveries, report the unexpected, and spark further research. Preparation of a case report can be a great learning experience, especially for medical students, residents, and young physicians. It serves as an excellent introduction to academic writing, familiarizing them with all aspects of publishing, from a structured case presentation and literature review to submitting and revising a manuscript. It can also stimulate an interest in a specific topic and gradually lead to more involved and complex academic endeavors.

Once a manuscript is submitted, the journal editor decides whether the manuscript merits further peer review, and the section editor or editor-in-chief reviews those comments and makes a decision that is conveyed to the corresponding author. Almost all accepted manuscripts require revisions of some kind. One of the good things about writing a case report is that it does not usually require major revisions; for the most part, comments can be addressed rather quickly with a few changes. The most common revisions requested are providing followup imaging information or additional laboratory/pathology information, shortening the length, and modifying sentences that boast of a major conclusion based on a single case. This article focuses on how to deal with the revision process so that it is smooth for both the author and the editor; and that it leads to a quick acceptance.

Open-access publishing, which removes monetary and legal restrictions from Internet reading, provides benefits for readers and publishers alike. Radiology Case Reports has used an open-access publishing model from its inception.

Primary cardiac tumors are rare and are usually diagnosed at an advanced stage due to nonspecific symptoms. We report a 46-year-old female who presented to our institution with shortness of breath and was diagnosed with a cardiac spindle-cell tumor. Wide surgical resection is the cornerstone for therapy for cardiac sarcomas. Our patient was considered inoperable due to the extent of the tumor.

OBJECTIVE. The purpose of this article is to familiarize radiologists with uncommon presentations of hepatocellular carcinoma (HCC) with an emphasis on the CT spectrum of atypical appearances. CONCLUSION. HCC is the fifth most common neoplasm worldwide and the second most common cause of cancer-related death. In many cases, HCC can be confidently diagnosed with noninvasive imaging. However, there are numerous unusual appearances of HCC with which the radiologist must be familiar.

Objective To illustrate the imaging appearances of a spectrum of renal collision and composite tumors. Occurrence of collision and composite tumors in the genitourinary tract is rare compared to the usual occurrence of synchronous tumors. Methods Case studies were chosen that represent the different tumors. Analysis was made on both the imaging and the pathology if excision was performed. Results Presence of 2 different cell types can lead to confusing imaging findings, and biopsy or excision is typically needed for final diagnosis. Some composite tumors have a characteristic appearance on imaging based on their pathologic features. Conclusion Familiarity with imaging findings may help radiologists include these tumors in their differential diagnosis.