Intravenous Contrast Injection Research Articles

Imaging of Ulcerative Colitis: The Role of Diffusion-Weighted Magnetic Resonance Imaging.

Magnetic resonance imaging (MRI) has emerged as a promising and appealing alternative to endoscopy in the objective assessment of patients with inflammatory bowel disease (IBD). Diffusion-weighted imaging (DWI) is a specialized imaging technique that enables the mapping of water molecule diffusion within biological tissues, eliminating the need for intravenous gadolinium contrast injection. It is expanding the capability of traditional MRI sequences in Ulcerative Colitis (UC). Recently, there has been growing interest in the application of intravoxel incoherent motion (IVIM) imaging in the field of IBD. This technique combines diffusion and perfusion information, making it a valuable tool for assessing IBD treatment response. Previous studies have extensively studied the use of DWI techniques for evaluating the severity of activity in IBD. However, the majority of these studies have primarily focused on Crohn's disease (CD), with only a limited number of reports specifically examining UC. Therefore, this review briefly introduces the basics of DWI and IVIM imaging and conducts a review of relevant studies that have investigated its application in UC to show whether these techniques are useful techniques for evaluating patients with UC in terms of detection, characterization, and quantification of disease activity. Through the extensive literature survey, most of these studies indicate that DWI proves valuable in the differential diagnosis of UC and could be used as an effective modality for staging UC.

Dynamic contrast enhancement and wall enhancement index for the quantitative assessment of vascular wall abnormalities in intracranial atherosclerosis: a pilot study

Background: Breakthrough neurotechnologies have allowed for new understanding of some brain disorders; however, identification and differential diagnosis of intracranial stenotic and occlusive lesions remains challenging. Magnetic resonance imaging (MRI) with dynamic contrast enhancement (DCE) is a tool that could be used for the quantitative assessment of endothelial permeability and microvascular volume in atherosclerotic plaques (AP). Aim: To assess quantitative parameters of vascular wall abnormalities in AP area and in obviously unchanged wall of intracranial arteries with MRI DCE and high spatial resolution Т1-weighed images before and after contrast injection, with calculation of the wall enhancement index (WEI) by mathematical modelling. Methods: This was a pilot cross-sectional uncontrolled study with consecutive recruitment of 29 patients with atherosclerotic abnormalities of brachiocephalic arteries, including intracranial. The patients’ median age was 66 [57; 72] years; they were mostly men (75.9%, n = 22). For the assessment of any brain abnormalities, MRI (magnetic induction 3 Tesla, Magnetom Prisma, Siemens) was performed in patients with standard sequence (Т2, T2-FLAIR), as well as MRI DCE for the assessment of intracranial arteries, before and after intravenous contrast injection, with high spatial resolution T1-weighed imaging and suppression of the signal from bloodstream and fat, with the calculation of WEI. Results: There were significant differences in WEI in AP and in unchanged wall (0.962 [0.686; 1.387] vs. 0.111 [0.014; 0.206], p 0.001). No significant differences were found between WEI values in internal carotid arteries APs (0.722 [0.573; 1.580]), middle cerebral arteries (0.921 [0.725; 1.183]), and basilar artery (1.343 [1.002; 1.419]) (p = 0.381). We also found significant difference (p = 0.034) in the extravascular extracellular fraction volumes ve (Tofts) in AP located in the basilar artery (0.171 [0.146; 0.325]), internal carotid arteries (0.579 [0.358; 1.000]), and middle cerebral arteries (0.134 [0.101; 0.269]). Conclusion: This is the first description of quantitative parameters characterizing vascular wall abnormalities in intracranial atherosclerosis. Despite its obviously intact state, vascular walls outside the intracranial AP was shown to be abnormal as well.

Early bifurcation of the common hepatic artery: A pitfall that should be known and recognized

Early bifurcation of the common hepatic artery (EBCHA) is a rare anatomical variation (1%), that is often overlooked but can lead to accidental ligation of the right branch of the hepatic artery with consequent arterial ischemia of the right liver and potentially very serious complications during pancreaticoduodenectomy, partial hepatectomy, or liver harvesting for transplantation. It may be difficult to diagnose EBCHA using transverse imaging sections. However, on standard CT sections with intravenous contrast injection, three warning signs should allow the image reader to suspect it: presence of two hepatic arteries to the right of the celiac trunk, presence of a retro-portal hepatic artery, and absence of a right hepatic artery arising from the superior mesenteric artery. Analysis of the CT with reconstruction then allows for definitive diagnosis and limits the risk of accidental arterial injury or ligation.

Pathomorphological features of confirmed bronchogenic cyst with atypical localization

Among all formations of the mediastinum in the adult population, cysts make up about 20 %, of which more than 60 % are bronchogenic cysts, where up to 50% have an asymptomatic course, and therefore in most cases are detected accidentally. Regardless of the course and origin, cysts are subject to complete surgical removal. In connection with the clinical and radiological polymorphism of bronchogenic cysts, histological confirmation of the origin of the cysts does not lose its relevance. The purpose of the work is to study and highlight the pathomorphological characteristics of a cyst localized in the pericardium. Using video-assisted thoracic surgery (VATS) and thoracotomy approaches, 16 people aged 28 to 62 with cystic lesions of the mediastinum were operated on. The patients underwent radiographic examination, computed tomography with intravenous contrast injection and, in 2 cases, magnetic resonance imaging. Ultrasound examination was performed on 6 patients in whom cystic lesions were a diagnostic finding. The location of the cyst, maximum diameter, density, and calcification were evaluated. Clinically and radiologically, asymptomatic pericardial (coelomic) cysts were detected in 2 persons in the prevascular department. In the visceral part of the mediastinum, 3 patients had a pericardial cyst, 10 patients were diagnosed with 10 bronchial cysts with parenchymal and perihilar localization, among which one patient was diagnosed with an asymptomatic bronchial cyst with an atypical localization in the pericardium. In the paravertebral part of the mediastinum, 1 paraesophageal cyst was established, which was intimately connected with the lower third of the thoracic part of the esophagus. All types of cysts were histologically confirmed. Statistical processing of the obtained results was carried out using the Excel program. After a clinical examination of a patient with a pericardial cyst of the visceral mediastinum, right VATS surgery and removal of the cyst was performed. Histological examination of fragments of the cyst wall showed the presence of multi-rowed ciliated cylindrical epithelium, pronounced infiltration by lymphoid elements with hemorrhages and foci of fibrotization in separate areas. The histological structure of the removed pericardial cyst confirmed its bronchogenic origin. So, we discovered a rare form of abnormality of embryonic growth of the ventral part of the foregut with localization of a bronchogenic cyst in the anterior-inferior mediastinum on the right, which significantly expanded the understanding of the disease.

Current status of optoacoustic breast imaging and future trends in clinical application: is it ready for prime time?

Optoacoustic imaging (OAI) is an emerging field with increasing applications in patients and exploratory clinical trials for breast cancer. Optoacoustic imaging (or photoacoustic imaging) employs non-ionizing, laser light to create thermoelastic expansion in tissues and detect the resulting ultrasonic emission. By combining high optical contrast capabilities with the high spatial resolution and anatomic detail of grayscale ultrasound, OAI offers unique opportunities for visualizing biological function of tissues in vivo. Over the past decade, human breast applications of OAI, including benign/malignant mass differentiation, distinguishing cancer molecular subtype, and predicting metastatic potential, have significantly increased. We discuss the current state of optoacoustic breast imaging, as well as future opportunities and clinical application trends. CLINICAL RELEVANCE STATEMENT: Optoacoustic imaging is a novel breast imaging technique that enables the assessment of breast cancer lesions and tumor biology without the risk of ionizing radiation exposure, intravenous contrast, or radionuclide injection. KEY POINTS: • Optoacoustic imaging (OAI) is a safe, non-invasive imaging technique with thriving research and high potential clinical impact. • OAI has been considered a complementary tool to current standard breast imaging techniques. • OAI combines parametric maps of molecules that absorb light and scatter acoustic waves (like hemoglobin, melanin, lipids, and water) with anatomical images, facilitating scalable and real-time molecular evaluation of tissues.

Osteolytic lesion in primary intracranial meningioma: A case report

Background: Hyperostosis of the skull is one of the characteristics of intracranial meningioma. In contrast, osteolytic lesions are very rarely discovered in meningioma. This study presented a rare instance of intracranial meningioma accompanied by significant osteolytic lesions. Case presentation: A 70-year-old male patient presented with a chief complaint of a left-sided scalp lump which developed progressively within two years. Seizures and right-sided weakness have been reported. A mass of approximately 8 cm in diameter with a smooth surface was noted during a physical examination. The brain magnetic resonance imaging revealed an ± 10 x 9.6 x 8.6 cm lobulated homogeneous mass on the left temporoparietal region and heterogeneously enhanced after intravenous contrast injection. A localized osteolytic lesion was detected extending from the left temporal region to the left parietal region. A craniectomy was performed to obtain the pathological diagnosis and for complete removal of the mass. Histopathological evaluation revealed the presence of an atypical meningioma. Conclusion: Bone destruction by meningioma may occur because of either neoplastic infiltration or pressure erosion.

Relationship between Eccentricity and Volume Determined by Spectral Algorithms Applied to Spatially Registered Bi-Parametric MRI and Prostate Tumor Aggressiveness: A Pilot Study.

(1) Background: Non-invasive prostate cancer assessments using multi-parametric MRI are essential to the reliable detection of lesions and proper management of patients. While current guidelines call for the administration of Gadolinium-containing intravenous contrast injections, eliminating such injections would simplify scanning and reduce patient risk and costs. However, augmented image analysis is necessary to extract important diagnostic information from MRIs. Purpose: This study aims to extend previous work on the signal to clutter ratio and test whether prostate tumor eccentricity and volume are indicators of tumor aggressiveness using bi-parametric (BP)-MRI. (2) Methods: This study retrospectively processed 42 consecutive prostate cancer patients from the PI-CAI data collection. BP-MRIs (apparent diffusion coefficient, high b-value, and T2 images) were resized, translated, cropped, and stitched to form spatially registered BP-MRIs. The International Society of Urological Pathology (ISUP) grade was used to judge cases of prostate cancer as either clinically significant prostate cancer (CsPCa) (ISUP ≥ 2) or clinically insignificant prostate cancer (CiPCa) (ISUP < 2). The Adaptive Cosine Estimator (ACE) algorithm was applied to the BP-MRIs, followed by thresholding, and then eccentricity and volume computations, from the labeled and blobbed detection maps. Then, univariate and multivariate linear regression fittings of eccentricity and volume were applied to the ISUP grade. The fits were quantitatively evaluated by computing correlation coefficients (R) and p-values. Area under the curve (AUC) and receiver operator characteristic (ROC) curve scores were used to assess the logistic fitting to CsPCa/CiPCa. (3) Results: Modest correlation coefficients (R) (>0.35) and AUC scores (0.70) for the linear and/or logistic fits from the processed prostate tumor eccentricity and volume computations for the spatially registered BP-MRIs exceeded fits using the parameters of prostate serum antigen, prostate volume, and patient age (R~0.17). (4) Conclusions: This is the first study that applied spectral approaches to BP-MRIs to generate tumor eccentricity and volume metrics to assess tumor aggressiveness. This study found significant values of R and AUC (albeit below those from multi-parametric MRI) to fit and relate the metrics to the ISUP grade and CsPCA/CiPCA, respectively.

Analisis Multi Slice Computed Tomography (MSCT) Nasofaring Dengan Klinis Karsinoma Nasofaring Di Instalasi Radiodiagnostik RSUP Dr. Hasan Sadikin Bandung

Background: Nasopharyngeal carcinoma is cancer that occurs in the nasopharyngeal mucosa which shows squamous cell differentiation. MSCT has become a reliable imaging technique for assessing the extent of nasopharyngeal carcinoma. Nasopharyngeal MSCT examination procedure with clinical nasopharyngeal carcinoma at the Radiodiagnostic Installation of Dr. RSUP. Hasan Sadikin Bandung uses a head protocol and slice thickness of 3-5 mm. This study aims to determine the Nasopharyngeal MSCT examination procedure for clinical nasopharyngeal carcinoma using a head protocol with manual intravenous contrast injection.&#x0D; Method: The type of research used is descriptive qualitative research with a case study approach. This research was conducted at the Radiodiagnostic Installation of RSUP Dr. Hasan Sadikin Bandung The subjects in this study consisted of three patients, two radiographers and three radiologists. Data collection methods are carried out through observation, interviews and documentation. The data analysis technique used is an interactive analysis model.

Patient Experience during Contrast-Enhanced Computed Tomography Examination: Anxiety, Feelings, and Safety

Introductions: Computed tomography is one of the biggest breakthroughs in diagnostic imaging. In order to more accurately assess structures and pathological changes during the examination, it is necessary to administer a contrast agent. Patients presenting for the examination, very often only find out during the examination that a contrast agent is required. This increases patients’ uncertainty when giving written consent for contrast administration, as well as anxiety about the examination. The aim of this study was to explore the experiences of patients who have contrast-enhanced CT scans, focusing primarily on anxiety, feelings, and safety. Methods: The cross-sectional study was conducted in diagnostic imaging offices in Pomeranian Voivodeship in 2019–2020. The survey was aimed at patients presenting for CT examinations with intravenous contrast injection. In total, 172 patients participated in the survey. A proprietary survey questionnaire was used to conduct the study. Results and Conclusions: During a CT scan, intravenous contrast agent administration is often necessary. Although there are few studies on patients’ experiences with this examination, the authors observe that some patients experience anxiety. The results of our study showed the following: (1) 30.8% of patients experience anxiety before a CT scan with intravenous contrast injection; (2) variables such as gender, previous experience, and searching for information about the examination influence the occurrence of anxiety; (3) the most common feelings experienced by patients during intravenous contrast injection are a sensation of warmth spreading throughout the body; (4) the most common source of information about the study used among patients was the Internet; (5) most patients feel safe during a CT scan.

Washout-Computed Tomography Discriminates Pulmonary "Fat-poor" Hamartomas From Neuroendocrine Neoplasms: A Simple Method in the Radiomics Era.

Pulmonary hamartomas (HAs) and neuroendocrine neoplasms (NENs) are often impossible to discriminate using high-resolution computed tomography (CT) as they share morphologic features. This challenge makes differential diagnosis crucial as HAs are invariably benign, whereas NENs must be considered malignant, thus requiring them to be evaluated for surgical excision.Our aim was, therefore, to develop a simple method to discriminate between pulmonary "fat-poor" HAs and NENs using contrast-enhanced CT (CECT). Between September 2015 and December 2021, 95 patients with a histologically proven diagnosis of lung NENs (74) and HAs (21) and who underwent a preoperative CECT scan were initially identified through a review of our pathologic and radiologic databases. Among these, 55 cases (18 HAs and 37 NENs), which have been studied with biphasic CECT, were ultimately selected and reviewed by 3 radiologists with different levels of experience, analyzing their morphologic and enhancement features.The enhancement analysis was performed by placing a region of interest within the lesion in noncontrast (NCp), postcontrast (PCp, 55 to 65s after intravenous contrast injection), and delayed phases (Dp, 180 to 300s). A subgroup of 35 patients who underwent 18FDG-PET/CT was evaluated in a secondary analysis. HU values were significantly different between NENs and HAs in the PCp ( P <0.001). NCp and Dp attenuation values did not show significant differences in the 2 groups. Differences in values of HUs in PCp and Dp allowed to discriminate between NENs and HAs. Wash-out analysis, ΔHU (PCp-Dp), can perfectly discriminate pulmonary "fat-poor" HAs from NENs.

Can Machine Learning Identify the Intravenous Contrast Dose and Injection Rate Needed for Optimal Enhancement on Dynamic Liver Computed Tomography?

This study aimed to investigate whether machine learning (ML) is useful for predicting the contrast material (CM) dose required to obtain a clinically optimal contrast enhancement in hepatic dynamic computed tomography (CT). We trained and evaluated ensemble ML regressors to predict the CM doses needed for optimal enhancement in hepatic dynamic CT using 236 patients for a training data set and 94 patients for a test data set. After the ML training, we randomly divided using the ML-based (n = 100) and the body weight (BW)-based protocols (n = 100) by the prospective trial. The BW protocol was performed using routine protocol (600 mg/kg of iodine) by the prospective trial. The CT numbers of the abdominal aorta and hepatic parenchyma, CM dose, and injection rate were compared between each protocol using the paired t test. Equivalence tests were performed with equivalent margins of 100 and 20 Hounsfield units for the aorta and liver, respectively. The CM dose and injection rate for the ML and BW protocols were 112.3 mL and 3.7 mL/s, and 118.0 mL and 3.9 mL/s ( P < 0.05). There were no significant differences in the CT numbers of the abdominal aorta and hepatic parenchyma between the 2 protocols ( P = 0.20 and 0.45). The 95% confidence interval for the difference in the CT number of the abdominal aorta and hepatic parenchyma between 2 protocols was within the range of predetermined equivalence margins. Machine learning is useful for predicting the CM dose and injection rate required to obtain the optimal clinical contrast enhancement for hepatic dynamic CT without reducing the CT number of the abdominal aorta and hepatic parenchyma.

Impacts of Gadolinium-Based MRI contrast Agent on Hematological and Biochemical Tests for the Human Volunteers.

Magnetic resonance imaging (MRI) Gadolinium-Containing contrast agents are used in combination with MRI in some situations. The effects of gadolinium-based MRI contrast agent (MAGNEVIST® Gadopentetate Dimeglumine Injection Bayer Standard 469 mg/ml (0.5 mmol/ml) on some hematological and biochemical tests for human male volunteers have been investigated. The study consisted of nine healthy individuals of human male volunteers; they were injected with intravenous (IV) contrast without being exposed to MRI. The cases are divided into four subgroups based on how long and how many times of blood samples were withdrawn after the intravenous (IV) contrast injection (9, 25, and 40 minutes). Blood samples were examined for twenty-seven hematological and biochemical parameters. The results proved that; after 9 min of injection with IV contrast, the WBCs count, LYM, MID%, and ALT decreased by 6%,6%, 4%, and 5%, respectively, and the concentration of GRA% and ESR increased by 5%. 25min after injection, concentrations of PLT increased significantly (P &lt; 0.05) by 4%, PCT %, LPCR %, MID, and ESR are increased non-significantly (P &gt; 0.05) by 4%, 5%, 7%, and 26%, respectively. After 40min of injections; MID, and MID% increased by 11% and 12%, respectively, and AST decreased by 4%. The maximum rise in ESR was increased by 31%. There was no substantial variation with time can be seen in electrolytes; Sodium (Na+), Potassium (K+), and Chloride (Cl-) under the effect of the intravenous contrast injection.

Real-Time Split-Dose PET/CT-Guided Ablation Improves Colorectal Liver Metastasis Detection and Ablation Zone Margin Assessments without the Need for Repeated Contrast Injection.

Real-time split-dose PET can identify the targeted colorectal liver metastasis (CLM) and eliminate the need for repeated contrast administration before and during thermal ablation (TA). This study aimed to assess the added value of pre-ablation real-time split-dose PET when combined with non-contract CT in the detection of CLM for ablation and the evaluation of the ablation zone and margins. A total of 190 CLMs/125 participants from two IRB-approved prospective clinical trials using PET/CT-guided TA were analyzed. Based on detection on pre-TA imaging, CLMs were categorized as detectable, non-detectable, and of poor conspicuity on CT alone, and detectable, non-detectable, and low FDG-avidity on PET/CT after the initial dose. Ablation margins around the targeted CLM were evaluated using a 3D volumetric approach. We found that 129/190 (67.9%) CLMs were detectable on CT alone, and 61/190 CLMs (32.1%) were undetectable or of poor conspicuity, not allowing accurate depiction and targeting by CT alone. Thus, the theoretical 5- and 10-mm margins could not be defined in these tumors (32.1%) using CT alone. When TA intraprocedural PET/CT images are obtained and inspected (fused PET/CT), only 4 CLM (2.1%) remained undetectable or had a low FDG avidity. The addition of PET to non-contrast CT improved CLM detection for ablation targeting, margin assessments, and continuous depiction of the FDG avid CLMs during the ablation without the need for multiple intravenous contrast injections pre- and intra-procedurally.

Are Diagnostic Computed Tomography Chest Scans Sufficient for Detecting Supraclavicular in Initial Breast Cancer Staging?

<h3>Purpose/Objective(s)</h3> Initial staging workup strategies for locally advanced or suspected stage IV breast cancer can include computed tomography (CT) of the chest, abdomen, pelvis (CAP) and bone scan or, alternatively, a whole-body positron emission tomography/computed tomography (PET/CT). Variations in intravenous contrast injection site and bolus timing, arm positioning, and acquisition techniques on a CT chest scan could limit visualization of supraclavicular (SCV) and supracricoid cervical lymph nodes, which are critical for staging, prognosis, and treatment recommendations. The study's purpose is to determine whether there is a difference between the incidences of SCV and cervical lymphadenopathy detected on staging CT CAP versus PET/CT scans. <h3>Materials/Methods</h3> The records of consecutive newly diagnosed breast cancer patients who received initial staging scans at a single institution from 2012 to 2017 were reviewed in a HIPAA compliant, institutional review board-approved study. De-identified information was reviewed for inclusion: new breast cancer diagnosis, >18 years old, and availability of staging. Exclusion criteria were prior breast cancer treatment, re-staging for known recurrence, and nondiagnostic imaging examinations. Radiology reports were searched for SCV and cervical lymphadenopathy to determine the incidence detected by each imaging modality. A board certified neuroradiologist reviewed and characterized scans that noted cervical or SCV lymphadenopathy. <h3>Results</h3> The initial search resulted in 3,126 PET/CT and 631 CT CAP scans with 588 patients fulfilling the inclusion criteria. PET/CT scans had been performed in 539 patients and 49 received CT CAP and bone scans. The two groups were well matched by stage (Table 1). Metastatic cervical lymphadenopathy was detected by PET-CT in 50 patients (7.9%) versus two (3.7%) with CT CAP. Out of the 50 patients who had cervical lymphadenopathy detected by PET-CT, 30 (60%) had metastatic cervical lymphadenopathy above the level of the lung apex, the typical upper extent of a CT chest field of view. Although 25 (50%) patients had additional areas of distant metastatic disease, cervical lymphadenopathy above the thoracic inlet was the only site of distant metastasis for 13 patients (26%), and would not have been detectable by CT CAP. <h3>Conclusion</h3> PET/CT detected more cervical and SCV lymphadenopathy than CT CAP in initial staging scans for breast cancer, with 60% of those detected on PET/CTs in areas that would have been occult on standard CT chest scans. Such nodal involvement constituted the only site of distant metastatic disease in 26% of the patients. Thus, dedicated CT neck imaging may be a reasonable addition to CT CAP as an initial staging strategy to determine accurate staging and radiation treatment field volumes and borders.

Cystic Teratoma of the oral cavity

We present a rare case of sublingual cystic teratoma in the oral cavity with atypical magnetic resonance imaging (MRI) findings in a 4-year-old girl. The MRI demonstrated a well-marginated lesion in the oral cavity floor, high signal on T2-and iso signal on T1-weighted with thick wall and wall enhancement after intravenous contrast injection. The MRI findings were related to a congenital cyst of the oral cavity with a high proteinaceous material, suggesting an infected ranula. The cyst was surgically removed. The histopathological section of the excised specimen demonstrated a cyst line by epidermoid stratified squamous epithelium and ciliated respiratory mucosa, compatible with maturing cystic teratoma.

Not Just Blood: Brain Fluid Systems and Their Relevance to Cerebrovascular Diseases.

Not Just Blood: Brain Fluid Systems and Their Relevance to Cerebrovascular Diseases.

Intravenous Injection of Contrast to Assess Colonic Anastomosis in Non-emergent Colorectal Surgery Does Not Reduce Anastomotic Leak Rate: A Retrospective Analysis Using the NSQIP Database

Intravenous Injection of Contrast to Assess Colonic Anastomosis in Non-emergent Colorectal Surgery Does Not Reduce Anastomotic Leak Rate: A Retrospective Analysis Using the NSQIP Database

Power-Injectable Peripherally Inserted Central Catheter Tip Malposition After Power Injection of Intravenous Contrast Media for Computed Tomography Examinations

The aim of this study is to describe the incidence of peripherally inserted catheter tip (PICC) migration after power injection of intravenous contrast for computed tomography (CT) examinations. Retrospective review was conducted of all PICC power injections for CT examinations during the study period: October 16, 2017 through October 23, 2018. Review included evaluation of preinjection and postinjection topograms to assess PICC tip position. Chi-squared statistical analysis was applied. A total of 594 topograms were obtained of power-injectable PICCs during the study period in anticipation of power injection with iodinated contrast media. Of those, 550 patients had satisfactory preinjection topograms and available postinjection topograms; 43 (7.8%) demonstrated tip malposition attributable to power injection of contrast media. Anatomic side of PICC placement and subsequent malposition were independent variables by chi-square test (chi-square = .09, P = .76); 32 of 429 (7.5%) right-sided PICCs versus 11 of 121 (9.1%) left-sided PICCs demonstrated new malposition after contrast media power injection. No complications related to power injection of contrast media through these PICCs were observed. PICC tip malposition secondary to power injection of iodinated contrast media is common and readily identifiable. Obtaining both preinjection and postinjection topograms ensures appropriate catheter position during injection and upon patient departure. Rapid saline flush is a noninvasive maneuver that allows a high chance of successful repositioning of catheter tips. Power injection of contrast media through a power injectable PICC is safe.

Computed Tomography Enterography

Computed tomography enterography (CTE) is an abdominopelvic computed tomography (CT) tailored for evaluation of the small bowel. This multidetector CT examination uses neutral oral contrast to optimally distend small bowel. Patients are scanned after the rapid injection of intravenous contrast during peak bowel wall enhancement. CTE is excellent for the evaluation of many small bowel disorders, particularly Crohn's disease. The purpose of this article is to review CTE indications, contraindications, technique, safety considerations, and imaging findings of common small bowel diseases.

Diagnosis of Menière's disease on MRI: feasibility at 1.5 Tesla.

Menière's disease (MD) is clinically characterized by the triad sensorineural hearing loss, tinnitus and/or aural fullness, and vertigo. Endolymphatic hydrops (EH) is the histopathological basis associated with MD, which can be demonstrated on magnetic resonance imaging (MRI). Currently, most studies are done on a 3-T MRI scanner and to date it is believed that EH can only be demonstrated on a 3-T magnet. We report the feasibility of demonstrating EH on a 1.5-T scanner using the standard 20-channel head and neck coil and the current standard 4-h delayed intravenous gadolinium-enhanced three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequence. To investigate whether current standard 4-h delayed intravenous gadolinium-enhanced 3D-FLAIR imaging can demonstrate endolymphatic hydrops on a 1.5-T MRI scanner. The 3D-FLAIR sequence was taken from a 3-T MRI protocol and tested on a volunteer patient with clinically "definite" MD, after 4-h delayed intravenous contrast injection. Good image quality was obtained after reducing both the matrix and the bandwidth, with clear demonstration of EH. Subsequently, eight more patients with unilateral disease were imaged. Five patients had "definite" MD and four had "probable" MD. We imaged nine patients with unilateral disease and detected EH in eight of nine ears. One patient with "probable" MD did not show any abnormality, but the images were degraded by motion artifacts. At a cost of 2 min extra scanning time compared to a 3-T scanner, EH can be confidently demonstrated with the current standard 3D-FLAIR sequence on a 1.5-T magnet.