CAIPIRINHA-VIBE and GRAPPA-VIBE for liver MRI at 1.5 T: a comparative in vivo patient study.

OBJECTIVE: Three-dimensional T1-weighted (T1W) gradient recall echo volumetric interpolated breath-hold examination (VIBE) using generalized autocalibrating partially parallel acquisitions (GRAPPA) is one of the key sequences in liver magnetic resonance imaging (MRI) and is used for precontrast, dynamic postcontrast, and delayed postcontrast imaging. The purpose of this study is to compare image quality and liver lesion detection (LLD) on a shorter-duration T1W VIBE sequence using the controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) technique with the conventional T1W GRAPPA-VIBE sequence during a single liver MRI session on a 1.5-T Seimens scanner. METHODS: Twenty consecutive patients (9 women and 11 men; age range, 36-85 years) were included in this prospective study. All patients underwent a complete liver MRI on a 1.5-T magnet (Aera; Siemens Medical Systems, Erlangen, Germany) that consisted of a T1W (in/out-of-phase), T2W, DWI, and precontrast and postcontrast multiphasic images (late arterial, 50 seconds, 120 seconds, and 300 seconds) with GRAPPA-VIBE. The CAIPI-VIBE images were acquired for precontrast and at 300 seconds (5 minutes) postcontrast phases (6.9 seconds per phase) in addition to GRAPPA-VIBE (21 seconds per phase). The shorter time for the CAIPI-VIBE was selected to allow postprocessing of image acquisition in the setting of multi-late arterial phase (single breath hold) postcontrast images. Five radiologists independently analyzed image quality with predefined scores for liver edge sharpness, artifacts, fat saturation deficiency, visualization of the portal veins and hepatic veins, and LLD (size, <0.5-3.8 cm). Score 0 was suboptimal (inadequate), 1 was acceptable for diagnosis, and 2 was optimal (excellent). Kappa statistics were used to assess agreement among readers. Generalized linear mixed model with generalized estimation equation method was used to estimate and compare the LLD failure rates. RESULTS: No statistically significant difference was seen in the degree of reader variability between CAIPI-VIBE and GRAPPA-VIBE for all evaluated categories using multirater κ statistics. For the precontrast and 5-minutepostcontrast phase sequences, greater than 95% of images were considered to be of acceptable quality in all image quality categories for both sequences. Forty-one lesions were evaluated in 17 patients with total of 204 observations (n = 204) by 5 readers. For 5-minute postcontrast images, the LLD rate of CAIPI-VIBE (80%) was lower than GRAPPA-VIBE (84%) (P = 0.03) for small lesions (0.5-1.7 cm). There was no significant difference in lesion detection on precontrast images. CONCLUSIONS: At 1.5 T, the CAIPI-VIBE may be helpful in reducing scan time and demonstrates similar image quality compared with the traditional GRAPPA-VIBE. The CAIPI-VIBE has shorter breath-hold time requirement and thus can be an acceptable alternative for the precontrast and 5-minute postcontrast GRAPPA-VIBE in patients with breath-hold difficulties.

Brachytherapy in pelvic malignancies: a review for radiologists.

Brachytherapy, also known as sealed source or internal radiation therapy, involves placement of a radioactive source immediately adjacent to or within tumor, thus enabling delivery of a localized high dose of radiation. Compared with external beam radiation which must first pass through non-target tissues, brachytherapy results in less radiation dose to normal tissues. In the past decade, brachytherapy use has markedly increased, thus radiologists are encountering brachytherapy devices and their associated post-treatment changes to increasing degree. This review will present a variety of brachytherapy devices that radiologists may encounter during diagnostic pelvic imaging with a focus on prostate and gynecologic malignancies. The reader will become familiar with the function, correct position, and potential complications of brachytherapy devices in an effort to improve diagnostic reporting and communication with clinicians.

Multimodality imaging of common and uncommon peritoneal diseases: a review for radiologists.

Peritoneal disease can be caused by a wide spectrum of pathologies. While peritoneal disease is usually caused by primary or secondary malignancies, benign diseases can occur and mimic malignancies. This article begins with an overview of peritoneal embryology and anatomy followed by a detailed description of the multimodality imaging appearance of peritoneal diseases. Common diseases include peritoneal carcinomatosis, pseudomyxoma peritonei, lymphomatosis, sarcomatosis, and tuberculous peritonitis. The uncommon diseases which cause peritoneal disease include desmoid fibromatosis, desmoplastic small round cell tumor, malignant mesothelioma, well-differentiated mesothelioma, multicystic mesothelioma, papillary serous carcinoma, leiomyomatosis, extramedullary hematopoiesis, inflammatory pseudotumor and amyloidosis. This manuscript will help the radiologist become familiar with the different peritoneal spaces, pathways of spread, multimodality imaging appearance and differential diagnoses of peritoneal diseases in order to report the essential information for surgeons and oncologists to plan treatment.

POEMS Syndrome: A Rare Disease With A Challenging Diagnosis.

A complex conglomerate of symptoms, signs, and abnormalities are present with POEMS syndrome, making the diagnosis, management and follow-up a challenge. Recognizing the disease early on may be difficult. Many patients are initially misdiagnosed as having others disorders, for example: multiple myeloma. There is no standard treatment for patients diagnosed with POEMS syndrome.

Metastatic Ovarian Tumor Masquerading as Atypical Pneumonia.

Krukenberg tumor is a malignancy in the ovary from a primary lesion in the gastrointestinal tract and a metastatic signet ring cell adenocarcinoma to the ovary. Stomach is the most common primary site, but other organs can serve as a primary site. The lymphatic system is the most likely route for metastasis. CA 125 levels can be used for screening for early detection of ovarian metastasis as well as for monitoring the course of disease. The prognosis of Krukenberg tumor is poor and no curative treatment is currently available.

Local magnetic resonance imaging staging of rectal adenocarcinoma.

Successful multidisciplinary evaluation of potentially resectable rectal adenocarcinoma depends on high-resolution preoperative magnetic resonance imaging (MRI). Magnetic resonance imaging accurately identifies important risk factors of local recurrence and distant metastasis, thus facilitating enhanced preoperative prognostic stratification and treatment. When combined with appropriate neoadjuvant chemotherapy and total mesorectal excision, the treatment of rectal cancer has dramatically improved. Accurate local staging by MRI requires a robust combination of imaging sequences. Herein, we review MRI imaging and rectal anatomy related to the staging of rectal adenocarcinoma.

Malignant renal epithelioid angiomyolipoma with liver metastasis after resection: a case report with multimodality imaging and review of the literature.

Renal epithelioid angiomyolipoma (EAML) is a perivascular epithelioid cell tumor. Although the overwhelming majority of renal EAMLs are benign, cases of aggressive behavior and malignancy have been reported. Here, we report the case of a 62-year-old woman with a 12.5-cm renal EAML, who underwent resection and developed a 10.5-cm hepatic EAML 15 months after the surgery. Although multicentric disease is a possibility, the temporal course is consistent with metastasis from the poorly differentiated primary tumor. This is the only report with multimodality imaging to detail new metastatic disease during surveillance after intended curative resection of an EAML.

Interobserver agreement in distinguishing large adrenal adenomas and adrenocortical carcinomas on computed tomography.

PURPOSE: Large adrenal masses pose a diagnostic dilemma. The purpose of this study was twofold: first, to assess the degree of interobserver agreement in evaluating the morphology of pathologically proven adrenal adenomas and adrenocortical carcinomas larger than 4 cm in diameter; and second, to identify morphologic characteristics that correlated with the pathologic diagnosis. MATERIALS AND METHODS: For this blinded, retrospective study, we collected cases of 25 adrenal adenomas and 33 adrenocortical carcinomas measuring larger than 4 cm. Two radiologists evaluated morphologic characteristics of the lesions on CT. Interobserver agreement was evaluated using kappa statistics, and the correlation of imaging characteristics with the diagnosis was evaluated using a logistic regression model. RESULTS: We found the highest interobserver agreement in the assessment of precontrast attenuation (Κ = 0.81) as well as substantial agreement in determining the shape and the presence of calcifications (Κ = 0.69 and 0.74, respectively). Readers agreed less often regarding the presence of fat (Κ = 0.48), as well as regarding the presence of necrosis, heterogeneity, and the overall impression (Κ = 0.15, 0.24, and 0.26, respectively). CT characteristics correlated with benignity included round shape (p = 0.02), an overall radiologic impression of a benign lesion (p < 0.0001), the presence of fat (p = 0.01), and a precontrast attenuation of less than 10 Hounsfield units (p < 0.0001). The latter two of these characteristics were highly specific for benign pathology (93% and 100%, respectively). CONCLUSION: Our study suggests that CT has the ability to consistently identify characteristics significantly correlated with benign vs. malignant adrenal tumors.

Preexisting adrenal masses in patients with adrenocortical carcinoma: clinical and radiological factors contributing to delayed diagnosis.

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy that is usually large (>5 cm) at time of diagnosis. Delayed diagnosis significantly worsens survival. We describe adrenal gland morphology prior to ACC diagnosis and discern potential causes of delayed diagnosis. ACC patients seen at The University of Texas MD Anderson Cancer Center between 1998 and 2014 who had cross-sectional body imaging ≥3 months prior to their diagnosis. We conducted a detailed review of clinical and radiological features in these patients prior to ACC diagnosis. Of 439 patients with ACC, 25 had imaging preceding ACC diagnosis (5 with normal adrenal glands and 20 with preexisting masses). On the first available images, the median mass size was 2.8 cm (range 0-9) with median precontrast density of 36 Hounsfield units (range 17-43) and became 9 cm (range 1-18) at the time of ACC diagnosis. The median interval between first available image and ACC diagnosis was 20 months (range 3-89). In the 5 patients whose initial images showed normal adrenal glands, the time between the last normal scan and ACC diagnosis ranged from 5 to 36 months. The most common reason for delayed ACC diagnosis was the presumed benign status of the preexisting mass (n = 13, 65 %). Radiologically suspicious adrenal masses can precede ACC diagnosis and have variable growth patterns. ACC can also develop de novo within a few months in a radiologically documented normal adrenal gland. The presumed benignancy of preexisting masses based on size is the main reason for delayed ACC diagnosis.

Multimodality imaging of Epstein-Barr virus-associated inflammatory pseudotumor-like follicular dendritic cell tumor of the spleen: case report and literature review.

Inflammatory pseudotumors (IPTs) are rare tumors of unknown etiology; however, there is a strong association with the Epstein-Barr virus (EBV). EBV-positive IPTs are typically found in the liver and spleen. While many EBV-positive splenic IPTs contain follicular dendritic cell (FDC) proliferations, they are not aggressive such as with conventional FDC tumors. EBV-positive splenic IPTs have been reported with low malignant potential. We present a case with multimodality imaging of an EBV-positive IPT-like tumor with FDC features.

CT Dose Reduction Workshop: An Active Educational Experience.

PURPOSE: Improving patient safety by minimizing CT radiation dose, while maintaining diagnostic image quality, has become an important skill in diagnostic radiology. The aim of this study was to examine the value of an educational workshop for optimizing CT protocols in an academic department, and to assess its impact on resident education. METHODS: The CT Dose Reduction Workshop met monthly for 1 year, to teach and implement dose reduction strategies. Changes were made to CT protocols through group consensus while participants kept up to date with current literature. A survey was sent to 48 radiology residents and 32 attending radiologists in the department, including both participants and nonparticipants, after completion of the workshop, to assess its utility. The survey used a 5-point Likert-type scale. Average doses for a specific CT protocol before and after the workshop were compared. RESULTS: About 80% of respondents agreed or strongly agreed that the workshop was essential. Workshop participants expressed greater confidence in their knowledge of dose reduction techniques, with a mean score of 3.74 (95% confidence interval, 3.35-4.13), compared with nonparticipants, who had a mean score of 3.00 (95% confidence interval, 2.64-3.36) (P < .01). Dose reductions were established across numerous CT protocols. For instance, the average total dose-length product in renal mass protocol CT examinations decreased by 54% (P < .0001). CONCLUSIONS: A CT dose reduction workshop increases participants' confidence in knowledge of dose reduction techniques, fosters a culture of safety and quality improvement in the department, and reduces radiation dose to patients.

Ovarian thecal metaplasia of the adrenal gland in association with Beckwith-Wiedemann syndrome.

Beckwith-Wiedemann syndrome (BWS) is an overgrowth syndrome associated with increased risk to develop malignancies including adrenocortical carcinoma. Ovarian thecal metaplasia of the adrenal gland is a rare tumor-like mesenchymal lesion in BWS patients that lacks detailed radiological description. We report a 17-year-old female patient with BWS, associated with bilateral Wilms tumor, hepatic hemangiomatosis, pancreatic neuroendocrine tumor, and a phyllodes tumor of the right breast. Surveillance abdominal ultrasound identified a right adrenal mass that was further characterized by computed tomography and magnetic resonance imaging. Radiologically, this mass displayed features that overlap with adrenocortical carcinoma and pheochromocytoma but after pathological examination this proved to be an ovarian thecal metaplasia of the adrenal gland. Adrenal masses in BWS should raise the suspicion for adrenocortical carcinoma though other adrenal tumors including ovarian thecal metaplasia can be seen in these patients.