Impact of magnification views on the characterization of microcalcifications in digital mammography.

PURPOSE: To evaluate the additional benefit of true geometric (air-gap) magnification views for the characterization of microcalcifications in digital mammography. MATERIALS AND METHODS: After ethical approval, we retrospectively reviewed patient records to identify 100 patients with suspicious microcalcifications (35 malignant, 65 benign) who had a standard digital mammography and an additional digital magnification view in the same projection within three months. All images were obtained using an amorphous silicon-based full-field digital system (Senographe 2000 D, GE Healthcare, Chalfont St. Giles, UK). Images were independently analyzed by six board-certified radiologists. The probability of malignancy was estimated using first standard contact mammography alone (MG) and then mammography in combination with the magnification view (MG+MAG) using a modified Breast Imaging Reporting and Data System (BI-RADS) classification system and a percentage scale. Results were compared using receiver operating characteristic (ROC) analysis. In addition, readers assessed the subjective visibility of the calcifications. RESULTS: For all six readers combined, the area under the curve (AUC) was 0.664 ±â€Š0.052 for MG and 0.813 ±â€Š0.042 for MG + MAG, resulting in a statistically significant improvement of 0.148 ±â€Š0.120. Each reader had a higher AUC for MG + MAG than MG, with the improvement being statistically significant in four of the six readers. In 76.34 % of the cases, MG + MAG resulted in better visibility of calcifications compared with mammography alone. In 33 % slightly more and in 39 % significantly more calcifications were found. CONCLUSION: Even in digital mammography with the option of using electronic magnification (zoom) at the viewing workstation, true geometric (air-gap) magnification views remain important for the visibility and correct classification of microcalcifications and for the assessment of their extent.

[Consensus Meeting of Course Directors in Breast Imaging, 7 May 2011, in Frankfurt am Main--topic: MRI of the breast]. / Konsensustreffen der Kursleiter in der Mammadiagnostik am 7.5.2011 in Frankfurt am Main--Magnet-Resonanz-Tomografie der Mamma.

PURPOSE: The general gap in the BIRADS lexicon between lesion description and categorization leads to very different recommendations in clinical breast radiology. This is particularly true for breast MRI. The third consensus meeting of course directors in breast imaging aimed at an increase in standardization of breast MRI. MATERIALS AND METHODS: Between 166 and 344 participants in the audience (A) and 9 and 13 expert panel participants (P) took part in an electronic wireless voting system. The audience consisted of 98% radiologists and 2% gynecologists (A: n=295; P: n=12: radiologists 92%/gynecologists 8%). Of all participants, 62% had more than 10 years of experience in breast imaging and only 9% had less than 3 years of experience (P: 100%>10 years of experience). The day before 44, clinically relevant, though unresolved questions were formulated by the expert panel. For the evaluation a distinction was made between answers with a great majority (>75%), simple majority (50-<75%) and no majority (<50%) as well as answers from the expert panel and answers from the audience. RESULTS: Of 44 questions, all but two were answered with simple or great majority. CONCLUSION: Technique, reporting and clinical use are becoming more and more accurately defined in MRI of the breast and MR-guided interventions. The third consensus meeting of this kind gained numerous answers and thus enables recommendations for didactic as well as clinical routine work.

[Consensus Meeting of Course Directors in Breast Imaging, 9 May 2009, in Frankfurt am Main - Topic: Masses]. / Konsensustreffen der Kursleiter in der Mammadiagnostik am 9.5.2009 in Frankfurt am Main - Thema: Herdbefunde.

Fourteen directors of breast imaging courses met on behalf of the German Society of Radiology to discuss the actual standards of the diagnosis of masses. Open questions on the fields of mammography, breast ultrasound and breast MRI were elucidated by a presentation of one of the 14 panel members, followed by an electronic anonymous voting. Beside of the panel members, more than 300 participants of the consensus meeting contributed their opinions by electronic voting. Answers with definite majorities (> 75 %), answers with narrow majorities and those with missing majorities were discriminated from each other. The opinions of the plenum were compared to the majorities of the podium and showed only a few critical differences. Due to unequivocal majorities seven answers to important questions concerning the diagnosis of masses can lead to a further standardization of breast cancer diagnosis.

[Radiological features of breast cancer]. / Radiologische Morphologie des Mammakarzinoms.

When considering typical features of malignant lesions, the radiologist must differentiate between invasive cancers consisting of mass lesions and ductal carcinoma in situ, typically appearing as microcalcifications. Common malignant features of invasive cancers include irregular shape and indistinct or spiculated margins. In microcalcifications, segmental distribution and pleomorphic shape are the features with the highest predictive value of malignancy. However, there is a broad spectrum of findings that confound the reliable differentiation between benign and malignant lesions. The American College of Radiology has established the Breast Imaging Reporting and Data System (BI-RADS) for standardizing radiological terms and reports in mammography screening. The Breast Imaging Reporting and Data System provides diagnostic categories that have implications for guidance regarding follow-up or biopsy of mammographic breast lesions. BI-RADS 3 lesions are considered probably benign with a malignancy risk < 2%. These findings can be followed up at predetermined intervals according to current recommendations. Suspicious lesions with a substantial probability, but without the classic appearance of malignancy, are classified as BI-RADS 4. Minimal invasive biopsy should be considered in patients with these lesions. BI-RADS 5 lesions are highly suggestive of malignancy. It is recommended that appropriate action should be taken for these most suspicious lesions. The accuracy of the mammography as the primary diagnostic tool can be increased by the use of ultrasound and physical examination. In some situations, MRI is helpful for further evaluation. However, classifying the lesions with precision is not trivial since overlap exists between malignant and benign features.

Temporal arteritis with pauci-immune glomerulonephritis: a systemic disease.

Temporal arteritis is easily diagnosed and responds gratifyingly to treatment. Renal complications are unusual, but nevertheless occur. Earlier, an association between pauci-immune glomerulonephritis and temporal arteritis was shown. We present a patient who clearly had temporal arteritis but also developed cerebral hemorrhage, pulmonary infiltrates related to granulomatous pulmonary vasculitis, and pauci-immune glomerulonephritis. We suggest that temporal arteritis is neither always localized nor temporal. Instead, the condition can be a lethal, systemic disease. Renal involvement in patients with temporal arteritis is not common and the presence of glomerulonephritis is rare [Jennette and Falk 1994]. Lenz et al. [1998] described a patient who developed vision loss, optic nerve atrophy, elevated erythrocyte sedimentation rate, a positive rheumatoid factor and terminal glomerulonephritis. The renal biopsy showed focal and segmental necrotizing glomerulonephritis, despite negative antineutrophil cytoplasmatic antibodies (ANCA), antinuclear antibodies and antiglomerular basement membrane antibodies. Giant cells were identified in the necrotic vessel walls within the kidney. Immunofluorescence was negative and a diagnosis of ANCA-negative pauci-immune glomerulonephritis was made. The patient did not respond to immunosuppression and developed end-stage renal disease. Although the clinical attributes were consistent with temporal arteritis, no temporal artery biopsy was done in that patient. We recently treated a patient with temporal arteritis and pauci-immune glomerulonephritis. Our patient's course was somewhat different in comparison to the patient described by Lenz et al. [1998].

Spontaneous splenic hemorrhage in a patient with Wegener's granulomatosis.

We report the occurrence of spontaneous splenic hemorrhage in a patient with Wegener's granulomatosis. Pulmonary infiltrates, hemoptysis, and crescentic glomerulonephritis were accompanied by a progressive splenic enlargement with minimal abdominal symptoms. Magnetic resonance imaging was particularly helpful. The spleen was removed by minimally invasive endoscopic surgery. Subcapsular hemorrhage had occurred because of splenic vasculitis. Postoperatively, a remission was achieved by a combination of high-dose corticosteroids and cyclophosphamide.

Renal cell cancer: incidence of hemorrhage on MR images in patients with chronic renal insufficiency.

This study describes the occurrence of hemorrhage in renal cancer in patients with chronic renal insufficiency as shown on MR images. Thirteen consecutive patients with chronic renal insufficiency who had histologically proven renal cancer and underwent MRI at 1.5 T were entered in the study. MR examinations included spoiled gradient echo (SGE) and T1-weighted fat-suppressed imaging pre- and postgadolinium administration. All renal cancers were well shown on MR images and were most clearly depicted on postgadolinium T1-weighted fat-suppressed images. Tumors in 12 of 13 patients had regions of high signal intensity on precontrast T1-weighted images. Histology demonstrated intratumoral hemorrhage in all 12 of these patients. Four hemorrhagic tumors were largely cystic on imaging studies. One of these cancers altered in appearance from largely cystic with extensive hemorrhage to largely solid with substantial enhancement after a 2.5-year interval. Renal cancers demonstrated minimal enhancement (11 patients) on early postgadolinium images and were minimally enhanced on delayed images in 10 of 13 tumors. Two renal cancers demonstrated intense enhancement. Renal cancers are well shown on MR images in patients with chronic renal insufficiency. Because of the common occurrence of hemorrhage into renal cancers in patients with renal insufficiency, caution should be exercised when evaluating hemorrhagic cystic lesions in these patients.

Renal abscesses: appearance on gadolinium-enhanced magnetic resonance images.

PURPOSE: To determine the appearance of renal abscesses on gadolinium-enhanced magnetic resonance (MR) images, we reviewed 12 MR studies of eight patients with renal abscesses. These findings were compared with findings on other imaging modalities. METHODS: Eight patients underwent 12 MR studies at 1.5 T, including T1-weighted gradient echo and fat-suppressed spin echo pre- and post-Gd-DTPA enhancement. Two radiologists retrospectively reviewed the MR images and compared MR findings to the findings on contrast-enhanced computed tomography (CECT) in five patients, noncontrast computed tomography (NCCT) in two patients, and ultrasound in all patients. RESULTS: On contrast-enhanced MR images, renal abscesses were clearly depicted as heterogeneously low-signal-intensity lesions. Four patients had solitary abscesses, and four had multiple abscesses. Prominent perinephric inflammatory stranding was observed in six patients and was best shown on gadolinium-enhanced T1 fat-suppressed images. CECT findings were comparable to contrast-enhanced MR images, although contrast resolution was less on CECT images in all cases. Renal abscesses were poorly shown on NCCT and ultrasound images. CONCLUSION: Renal abscesses are clearly shown on gadolinium-enhanced MR images as low-signal-intensity lesions associated with prominent perinephric inflammatory strands. In this study, NCCT and ultrasound studies are poor at defining abscesses. Despite lesser contrast resolution of CECT versus MRI, the findings in cases of renal abscesses are similar. In patients with elevated serum creatinine, iodine contrast allergy, or the need for serial exams, MRI may be the best imaging technique to evaluate renal abscesses.

Contrast-enhanced MR imaging of the pancreas.

Recent MR techniques such as breath-hold imaging, fat suppression, and dynamic imaging after intravenous administration of gadolinium chelates have reduced artifacts in the abdomen, resulting in an increased role of MR imaging in the evaluation of pancreatic disease. The extracellular contrast agent gadolinium chelate has been shown to enhance normal pancreatic tissue in a homogeneous fashion. Contrast between normal pancreatic tissue and tumor tissue on T1-weighted images may be improved after administration of gadolinium. Because of the lesser vascularization of pancreatic ductal cancers as compared to the normal glandular tissue, the differences in signal intensity are often greatest in the capillary phase immediately after contrast administration. In addition, the hypervascular nature of islet cell tumors, results in good definition of primary tumor and liver metastases on immediate post-gadolinium images.

Enhancement of the normal pancreas: comparison of manganese-DPDP and gadolinium chelate.

The purpose of this paper was to compare manganese-DPDP (Mn-DPDP) and gadolinium chelate (Gd-DTPA) contrast agents for enhancement of the normal pancreas. A total of 14 patients with focal liver disease underwent Mn-DPDP- and Gd-DTPA-enhanced 1.5 T MR examinations using spoiled gradient-echo (FLASH) technique at two separate times. Contrast agents were injected according to the currently recommended practices; Gd-DTPA was injected as a rapid bolus injection in a dosage of 0.1 mmol/kg, and Mn-DPDP was injected as a slow IV injection in a dosage of 5 mumol/kg. Quantitative region of interest measurements were made in 11 patients, and percent contrast enhancement of the pancreas and pancreas-fat signal-to-noise ratios (SNR) were determined for each agent. Images were also evaluated qualitatively by consensus reading of two investigators and overall scan quality was rated on a scale from 1 (poor) to 4 (very good). Enhancement of the pancreas immediately post Gd-DTPA was significantly higher than 15 min post Mn-DPDP (73.3 vs 36.3%; p = 0.003). On postcontrast images the pancreas-fat SNR measurements were 7.7 (i.e., pancreas higher in signal than fat) and -6.1 for Gd-DTPA and Mn-DPDP, respectively, which was significantly different (p < 0.001). Image quality was rated as 3.1 and 2.5 for Gd-DTPA- and Mn-DPDP-enhanced images, respectively. The normal pancreas enhances significantly more with Gd-DTPA than with Mn-DPDP administered under the conditions of this study. Overall image quality is also greater on the Gd-DTPA-enhanced images.

MR findings in diffuse renal parenchymal disease.

This study evaluates the MR appearance of the kidney in diffuse renal parenchymal diseases, using precontrast, and immediate and delayed postgadolinium chelate (Gd), spoiled gradient echo (SGE), and pre- and post-Gd, T1-weighted, fat-suppressed spin-echo MR images to determine if characteristic findings exist for various types of renal disease. One hundred twenty-one patients with renal disease underwent MRI. Underlying diagnoses included: (a) glomerular disease (GD), (b) tubulointerstitial disease (TID), (c) microvascular disease (MVD), (d) ischemic nephropathy (INP), (e) obstructive nephropathy (ON), (f) infectious renal disease (IRD), (g) sickle cell disease (SCD), (h) renal cortical necrosis (CN), and (i) renal insufficiency of unknown etiology (UE). MR examinations of 22 patients with normal kidneys (NK) were evaluated as a control group. The presence of corticomedullary differentiation (CMD) demonstrated strong inverse correlation with serum creatinine concentration (SCr) (r = -.568, P < .001). Mean thickness of the renal cortex was 8.4 and 7.8 mm in patients with NK and Gd, respectively. The mean cortical thickness in patients with MVD, TID/Chemo, INP, and ON was 5.2, 5.6, 5.5, and 4.3 mm, respectively, significantly thinner than the renal cortex in the NK and GD groups (P < .01). Irregularity of the renal cortex was more frequent in MVD (60.9%), IRD (62.5%), ON (55.6%), and TID/other (53.8%) than in GD (3.8%) and NK (0%) (P < .01). Diffuse high SI of the entire medulla on delayed postcontrast images was observed in 25 (20.7%) of the patients with renal disease and none of the NK group. Although no pathognomonic features were found, certain findings were observed that may correlate with the etiology of the kidney disease and, therefore, assist in the differential diagnosis of renal parenchymal disease.

Multilocular cystic nephroma: MR imaging appearance with current techniques, including gadolinium enhancement.

The purpose of the study was to define the MRI appearance of multilocular cystic nephroma (MLCN), using current MR techniques, including gadolinium (Gd)-enhanced sequences. Seven patients with MLCN underwent MR imaging with the following sequences: T1-weighted spin echo with fat suppression (T1FS, five patients), T1-weighted spoiled gradient echo (SGE, seven patients), T2-weighted fast spin echo (two patients), and Gd-enhanced T1FS (seven patients) and SGE (seven patients). MLCN was histologically proven by resection of the mass in six patients and by observation of typical imaging features with stability in appearance over a 6-month period in one patient. Lesion morphology and signal intensity (SI) features were retrospectively evaluated. MRI features of MLCN included a solitary cystic lesion with thin internal septations in six patients and a cluster of closely grouped cysts similar in size in one patient. Individual cystic spaces demonstrated SI, varying from low to high on T1-weighted images in three patients and demonstrated low-to-intermediate SI in four patients. Herniation of the lesions into the renal collecting system and thin enhancing septa were demonstrated in all patients. A complex cystic renal lesion with enhancing septa and herniation into the renal collecting system are the characteristic MR findings of MLCN. The direct multiplanar capability of MR may optimally show the relationship of MLCN to the renal pelvis and, thus, facilitate correct diagnosis.

Comparison of gadolinium chelates with manganese-DPDP for liver lesion detection and characterization: preliminary results.

Nonspecific extracellular gadolinium chelate (NEGd) was prospectively compared with managanese (Mn)-DPDP (Mn) for the detection and characterization of focal liver lesions of various histology. Seventeen patients with known or suspected focal liver lesions underwent NEGd and Mn-enhanced studies at 1.5 T. Study findings were correlated with histology (five patients), computed tomography (CT) examinations (17 patients), and 4- to 13-month imaging follow-up by CT and/or MR (five patients). NEGd studies were performed as serial postcontrast spoiled gradient echo (SGE) sequences, and Mn studies were performed as SGE sequences 15 and 30 min postocontrast and T1-weighted, fat-suppressed spin echo at 16 min. NEGd and Mn images were prospectively interpreted in a separate blinded fashion. Lesion detection and characterization were determined. NEGd and Mn-enhanced images demonstrated 61 and 49 lesions, respectively (p = .1, NS). A total of 60 and 33 lesions were characterized on NEGd and Mn images, respectively, which was significantly different (p = .008). No differences were observed for the detection and characterization of liver metastases; whereas there was a trend for superior detection and characterization for hepatocellular carcinoma with NEGA.

MRI of acute cholecystitis: comparison with the normal gallbladder and other entities.

Our purpose was to prospectively compare MRI findings with histopathologic findings in the evaluation of suspected acute cholecystitis. Fourteen patients with clinically suspected acute cholecystitis were entered into the study. MR sequences included T1-weighted fat-suppression and breath-hold spoiled gradient echo (SGE) before and after intravenous gadolinium chelate administration. Percent contrast enhancement (%CE) of the gallbladder wall and gallbladder wall thickness (WT) were measured and liver enhancement patterns determined prospectively on MR images. Correlation was obtained with pathological findings at cholecytectomy in all patients. In a second phase of the study MR images on 10 additional subjects who underwent MR examination for reasons other than hepatobiliary disease were analyzed to determine normal values for %CE and gallbladder wall thickness. Mean %CE was 124.0% in patients with acute cholecystitis (10 patients), 58.0% in patients with chronic cholecystitis (2 patients), and 73.0% in patients with gallbladder malignancy (2 patients). Mean gallbladder WT was 6.1 mm in acute cholecystitis, 4.5 mm in chronic cholecystitis, and 6.0 mm in malignant disease. There was a significant difference in %CE between acute and chronic cholecystitis (p = 0.03); no other significant differences in %CE or WT were observed among the patients with gallbladder disease. Patients without biliary disease had %CE of 37.3% and WT of 2.9 mm, which were both significantly less (p < 0.001) than in patients with acute cholecystitis. Transient enhancement of pericholecystic hepatic parenchyma on immediate postgadolinium SGE images was seen in 7 of 10 patients with acute cholecystitis, and not observed in other patients. Patients with acute cholecystitis had increased %CE and WT on MR images that were significantly greater than normal and %CE that was significantly greater than in patients with chronic cholecystitis. Transient increased pericholecystic hepatic enhancement was observed in 70% of acute cholecystitis patients and in no other patient groups.

Correlation of perfusion abnormalities on CTAP and immediate postintravenous gadolinium-enhanced gradient echo MRI.

BACKGROUND: The purpose of this study was to evaluate patients with wedge-shaped perfusion defects seen on spiral CT arterial portography for the presence of transient increased wedge-shaped enhancement on dynamic gadolinium-enhanced gradient echo MR images. METHODS: Nineteen patients underwent CTAP and MRI within a 2-week interval. All patients with wedge-shaped perfusion defects on CT arterial portography were evaluated in a separate review session for the presence of transient increased segmental hepatic enhancement on dynamic gadolinium-enhanced spoiled gradient echo (SGE) MR images. RESULTS: Eight patients were identified to have subsegmental, segmental, or lobar wedge-shaped perfusion defects by CT arterial portography. In 8/8 patients, there was transient wedge-shaped increased hepatic enhancement on MR images which corresponded to the perfusion defects identified on CT arterial portography. Transient increased enhancement on MR images was observed on immediate postgadolinium images as high-signal intensity of the involved subsegment, segment, or lobe. This relatively high-signal area faded to near isointensity in all cases on images obtained at 45 s. CONCLUSION: Wedge-shaped perfusion defects demonstrated by CT arterial portography corresponded to wedge-shaped increased hepatic enhancement following gadolinium administration on SGE MR images.