Pearls and pitfalls in breast MRI.

At our academic institution, we have noticed repeated examples of both false-positive and false-negative MR diagnoses in breast cancer. The most common diagnostic errors in interpreting MRI of the breast are discussed in this review and experience-based advice is provided to avoid similar mistakes. The most common reasons for false-positive diagnoses are misinterpretation of artefacts, confusion between normal enhancing structures and tumours and, above all, insufficient use of the American College of Radiology breast imaging reporting and data system lexicon, whereas false-negative diagnoses are made as a result of missed tiny enhancement, a background-enhancing breast, or enhancement interpreted as benign rather than malignant.

[Tomosynthesis: luxury or necessity?]. / Tomosynthèse: luxe ou nécessité

Digital mammography is replacing conventional film-screen mammography. One of its advantages is to offer options of advanced processing such as tomosynthesis. Tomosynthesis allows to avoid the overlap of tissues depitected on mammograms, and potentially to improve the detection of subtle lesion such as architectural distortion, permits the characterization of masses and of density asymmetry and the accurate measurement of beast lesion by a better delineation of the lesion borders. Furthermore, in cases of superimposition mimicking an abnormality, it can show the lack of a significant finding and decrease the recall rate. However, additional studies are necessary to evaluate its added valve by comparison to mammography in consecutive patients and not only in retrospectively selectioned cases and to define its indication in diagnostic and screening.

[Does breast density have an impact on the indications for MRI?]. / La densité mammaire change-t-elle les indications d'IRM du sein?

MRI indications in breast imaging in breast imaging are now well codified. In diagnostic and screening, MRI in recommended in patients with likely metastatic lymph nodes and in metastasis of unknown cause, and in women with high risk family. In characterisation MRI is recommend in non-calcified subtle findings, non suitable for biopsy. In the staging of a diagnosed breast cancer, MRI has a great impact both for the diagnosis and for the treatment, event if group of women for whom MRI is recommended is still discussed. In follow-up of patients with an history of breast cancer, MRI permits to differentiate recurrence from scarr and to monitor the response to a neo-adjuvant chemotherapy. Dense breast don't constitute a MRI indication by itself, but strengthen recognized MRI indications. Fatty breast easily readable on mammogram don't justify not to perform MRI in the screening of women with high risk family. Conservely in the staging of a breast cancer in an woman or in the monitoring of a neo-adjuvant chemotherapy fatty breast may make US sufficient.

[Breast MRI in invasive lobular carcinoma: diagnosis and staging]. / Apport de l'IRM dans le diagnostic et le bilan d'extension des cancers lobulaires infiltrants.

PURPOSE: To assess the use of breast MRI for the diagnosis and staging of invasive lobular carcinoma and its impact on surgical management. MATERIALS AND METHODS: Retrospective study of 35 invasive lobular carcinoma, histologically diagnosed in 34 patients who underwent clinical exam, mammography, ultrasonography and magnetic resonance imaging. RESULTS: Enhancement at MRI was seen for all 35 cancers. It was focal for 24 patients, regional for 10 and diffuse for 1. The kinetic of the enhancement was characteristic of malignancy for 33 patients. For 11 patients the MRI staging was positive, finding 8 news cancers. For 3 patients MRI lead to biopsy of benign lesions but improved the surgical management in the 8 cases of new cancers: wider excision for 3 cases, planned breast conservation converted to mastectomy in 3 cases and excision of contralateral lesion in 2 cases. CONCLUSION: Breast MRI is useful in diagnosis, staging and surgical management of invasive lobular breast carcinoma.

The clinical value of preoperative wire localization of breast lesions by magnetic resonance imaging--a multicenter study.

To evaluate the clinical value of MRI guided preoperative wire localization of clinically and mammographically occult lesions of the breast. In a multicenter study, we evaluated 132 preoperative MRI guided localizations. Median lesion size evaluated by MRI prior to wire localization was 9mm. MRI guided localization was successfully performed in 96.2% of cases. Median wire deviation from the lesion was 0 (0-10) mm. Moderate bleeding with no further treatment required occurred in three patients. We conclude that MRI guided preoperative wire localization is a safe and accurate procedure in cases of clinically and mammographically occult lesions of the breast.

European quadricentric evaluation of a breast MR biopsy and localization device: technical improvements based on phase-I evaluation.

Our purpose was to report about technical success, problems and solutions, as experienced in a first multicentre study on MR-guided localisation or vacuum biopsy of breast lesions. The study was carried out at four European sites using a dedicated prototype breast biopsy device. Experiences with 49 scheduled localisation procedures and 188 vacuum biopsies are reported. Apart from 35 dropped indications, one localisation procedure and 9 vacuum biopsies were not possible (3 times space problems due to obesity, 2 times too strong compression, 3 times impaired access from medially, 2 times impaired access due to a metal bar). Problems due to too strong compression were recognised by repeat MR without compression. During the procedure problems leading to an uncertain result occurred in eight vacuum biopsies, two related to the procedure: one limited access, and one strong post-biopsy enhancement. Improvements after phase-I study concerned removal of the metal bar, development of an improved medial access, of a profile imitating the biopsy gun, optimisation of compression plates and improved software support. The partners agreed that the improvements answered all important technical problems.

Multicenter study for the evaluation of a dedicated biopsy device for MR-guided vacuum biopsy of the breast.

The purpose of this multicenter study was to determine the accuracy and clinical value of a dedicated breast biopsy system which allows for MR-guided vacuum biopsy (VB) of contrast-enhancing lesions. In five European centers, MR-guided 11-gauge VB was performed on 341 lesions. In 7 cases VB was unsuccessful. This was immediately realized on postinterventional images or direct follow-up combined with histopathology-imaging correlation; thus, a false-negative diagnosis was avoided. Histology of 334 successful biopsies yielded 84 (25%) malignancies, 17 (5%) atypical ductal hyperplasias, and 233 (70%) benign entities. Verification of malignant or borderline lesions included reexcision of the biopsy cavity. Benign histologic biopsy results were verified by retrospective correlation with the pre- and postinterventional MRI and by subsequent follow-up. Our results indicate that MR-guided VB, in combination with the dedicated biopsy coil, offers the possibility to accurately diagnose even very small lesions that can only be visualized or localized by MRI.

[Sudden death (III). The causes of sudden death. Problems at the time of establishing and classifying the types of death]. / Muerte súbita (III). Causas de muerte súbita. Problemas a la hora de establecer y clasificar los tipos de muerte.

Sudden cardiac death is one of the main causes of death in Western countries. Identification of possible causes and their intrinsic mechanisms, is directed to achieve a better risk stratification, which permits the obtention of a more effective primary and secondary prevention. In the last two decades, important advances in the field of arrhythmia treatment have been obtained, which could have an important impact on the incidence of sudden death in the highest risk groups. However, the low positive predictive value of the diagnostic tools available nowadays, as well as the high number of patients who have sudden death as the first initial symptom of their disease, represent an important limitation for the primary prevention on the whole of the general population. In this article we review different diseases associated with sudden death, with special focus on the subgroup of patients with higher risk within each disease group, as well as the problems in establishing an accurate definition of sudden death.

[Image of pseudocapture caused by micro-dislodgment of the electrode in a VDD pacemaker]. / Imagen de seudocaptura por microdesplazamiento del electrodo en un marcapasos VDD.

The new AV sequential pacemakers have improved the suitability for the election of the best pacing mode for each patient. The complexity of the systems may mask some dysfunctions. In the presented case, a failure to capture due to micro-dislodgment, may have been missed in a simple pacemaker control, because of the combination of several factors: the presence of normal AV conduction at that moment, the concordance between the pacemaker stimulus and the conducted QRS complex and the similar morphology of the conducted and paced QRS complex.

Ventricular arrhythmias in left ventricular hypertrophy and heart failure.

The significance of ventricular hypertrophy in the genesis of ventricular tachyarrhythmias cannot be over-emphasized. Left ventricular hypertrophy, as a consequence of arterial hypertension, influences the three factors involved in the prognosis and we express these as a triangle of risk: electrical instability, left ventricular dysfunction and ischaemia.

Do silent myocardial ischemia and ventricular arrhythmias interact to result in sudden death?

The relationship between silent myocardial ischemia and sudden death depends on the severity and duration of the ischemia. Severe, transmural and persistent ischemia, as occurs in myocardial infarction, can trigger sudden death. When the ischemia is severe and transmural but not long-standing (e.g., Prinzmetal angina), ventricular arrhythmias appear frequently, but they are rarely malignant. In cases of subendocardial ischemia, there is no definitive proof of this relationship.

Assessment of ovaries by magnetic resonance imaging in patients presenting with polycystic ovarian syndrome.

The demonstration of bilaterally enlarged ovaries with multiple small cysts at ultrasound is the morphological hallmark of polycystic ovarian syndrome (PCOS). However, a number of patients with clinical and biochemical diagnosis of PCOS have ovaries that are without sonographically visible discrete cysts. A better contrast resolution is obtained with magnetic resonance imaging (MRI) and enables visualization of organ structure not seen with other techniques. The purpose of the study was to relate the clinical and biochemical features of 10 patients presenting with a PCOS profile to magnetic resonance imaging and to compare these findings with those observed at ultrasound. With MRI, at least one ovary typical of PCOS could be visualized in eight patients, while this was the case in only three patients with ultrasound. The ultrasound examinations were indeed equivocal in the majority of patients (seven cases). No apparent relationship could be found between the clinical and biochemical parameters and ovarian morphology assessed by MRI or ultrasound. In summary, the present study supports the superiority of MRI technique to assess ovarian morphology over the ultrasound technology used in our study. However, the recent technological advances in ultrasound, and specifically the advent of high frequency transvaginal sonography, will be of particular interest in the study of PCOS.

Breast pathology in MRI. First results.

The authors present the first results of the assessment of MRI (0.35 T) with adapted surface reel in the exploration of mammary pathology in 90 cases. On a morphological level, MRI permits a new analysis of signs of dystrophy. As far as MRI is concerned, no specific sign of mammary neoplasia seems to exist. A classification is suggested, taking into account morphology and parameters of relaxation.

Ideal imaging in MR: contrast-enhancing pharmaceuticals. Evaluation of tempo carboxylic acid as nitroxide diagnostic agent.

The meglumine salt of TCA, a piperidinyl nitroxide stable free radical derivative, was tested as an NMR contrast enhancer. This report of its use in animals indicates its usefulness in the enhancement of signal intensity of the kidney and bladder.