MR-guided vacuum-assisted breast biopsy in the management of incidental enhancing lesions detected by breast MR imaging.

PURPOSE: The objective of this study was to determine the clinical value and accuracy of magnetic resonance (MR)-guided vacuum-assisted breast biopsy (VAB). MATERIALS AND METHODS: We retrospectively analysed 106 incidental breast lesions detected on MR imaging in 98 patients. Patients with nonpalpable suspicious lesions that were only MR visible were referred for MR-VAB performed with a 10-gauge needle. All patients with a VAB diagnosis of infiltrating carcinoma, carcinoma in situ or atypical epithelial hyperplasia were referred for surgery. Histopathology of the surgical specimen was considered the reference standard. RESULTS: MR-guided VAB was attempted in 29/106 lesions (27%); in 2/29 patients, the procedure could not be performed owing to failure to visualise the lesion. Lesions with clearly malignant features and borderline lesions (atypical ductal hyperplasias) were identified in 12 cases (44%) and benign entities in 15 (56%). Seven of 12 (58%) malignant lesions were <10 mm. Among the 27 successful MR-VAB procedures, VAB yielded one false-negative diagnosis (4%) and underestimation (4%). MR-guided VAB sensitivity and specificity were 92% and 100%, respectively, with a positive predictive value of 100% and a negative predictive value of 93%. CONCLUSIONS: The results of this study indicate that MR-guided VAB offers good accuracy in characterising nonpalpable breast lesions visible on MR imaging alone. Small lesion size (<1 cm) did not prove to be a limitation for the success of the procedure.

Utility of second-look ultrasound in the management of incidental enhancing lesions detected by breast MR imaging.

PURPOSE: To assess the utility of second-look ultrasound (US) for identifying and characterising incidental enhancing lesions detected by breast magnetic resonance imaging (MRI). MATERIALS AND METHODS: From among 655 consecutive breast MRI studies, 62 lesions (MRI visible, nonpalpable, occult at first-look US and mammography) were recommended for second-look US. MRI enhancement of lesions was mass-like in 59 cases (95%) and non-mass-like in three (5%). Forty-two lesions (68%) were ≤10 mm; only three lesions (5%) were >20 mm. Of all lesions, the Breast Imaging Reporting and Data System (BI-RADS) MRI category was highly suggestive of malignancy in six cases (10%), suspicious abnormality in 33 (53%) and probably benign in 23 (37%). The correlation between MRI lesion appearance, lesion size, histopathology findings and detection rate at second-look US were analysed. The reference standard was histopathology and/or follow-up (range 18-24 months). Statistical analysis was performed with the Fisher exact test. RESULTS: Second-look US identified 44 out of 62 (71%) lesions depicted at MRI. The detection rate at second-look US was higher for mass-like MRI lesions (75%) than non-mass-like lesions (0%), for lesion size >10mm (90%) and for BI-RADS 4 lesions (88%). Second-look US-guided biopsy detected 12 out of 17 (71%) malignant lesions. There was no correlation between the likelihood of carcinoma and the presence of a sonographic correlate. CONCLUSIONS: Second-look US is a reliable problem-solving tool in identifying and characterising most incidental MRI findings. It contributes to accurately selecting the cases in which MRI-guided biopsy is required.

Imaging of neuroendocrine gastroenteropancreatic tumours.

The role of imaging in functioning endocrine tumours (FETs) is primarily to detect the tumour, that is, to verify lesion number and location. Radiological detection of carcinoid tumours is limited by typical tumour location throughout the gastrointestinal tract or appendix and is therefore dependent on the tumour being large enough to make it recognisable in that site. The most common FET is insulinoma, which is commonly characterised by the typical appearance of a hypervascular lesion at multidetector-row computed tomography and magnetic resonance imaging. A particularly important role is played by intraoperative ultrasound in defining the exact number of lesions, their relationship with adjacent vascular structures and the pancreatic duct for the purposes of correct surgical planning (enucleation or resection). In the setting of nonfunctioning endocrine tumours (NFETs), which manifest late as large masses causing compression symptoms or as incidental findings, imaging is not primarily aimed at tumour detection, as this is relatively easy given the large size of the lesions. Rather, its role is to characterise the tumour and, in particular, to differentiate pancreatic NFET from ductal adenocarcinoma, as in comparison, malignant NFETs have a more favourable prognosis (5-year survival rate 40% compared with 3%-5% for adenocarcinoma) and therefore require different treatment approaches. As NFET are often malignant, they also require accurate staging and appropriate follow-up. In 80% of cases, NFETs have a "typical" imaging appearance: location in the pancreatic head, large dimensions (diameter between 5 and 15 cm, >10 cm in 30% of cases), capsule, sharp and regular margins owing to the expansile and noninfiltrative growth pattern, solid density and arterial hypervascularity. Some 20% of NFETs display different imaging characteristics ("atypical" appearance) as a result of arterial hypovascularity due to the presence of abundant fibrous stroma. Lastly, a small percentage of NFETs has yet a different appearance ("unusual") due to the cystic nature and/or diffuse location throughout the pancreatic parenchyma.

Role of multislice computed tomography in the diagnosis of gene-mutation-associated pancreatitis (GMAP).

PURPOSE: The aim of this study was to review the computed tomography (CT) features of the pancreatic parenchyma and ducts in patients with gene-mutation-associated pancreatitis (GMAP). MATERIALS AND METHODS: Twenty-five patients with GMAP were included in this retrospective study. Patients were divided into two groups according to the time interval between the onset of symptoms and the first CT examination (group A ≤24 months and group B >25 months). RESULTS: On qualitative image assessment, in group A patients, pancreatic duct stones were detected in 2/13 with GMAP. All stones were calcified and homogenous. Enhancement of the pancreatic parenchyma was hypovascular in 7/13 patients. In group B patients, pancreatic duct stones were detected in 12/12 with GMAP. Stones were calcified in 10/12 cases and noncalcified (protein plugs) in 2/12; in 5/10 cases, the calcified stones were heterogeneous with noncalcified central core (bull's-eye appearance). Enhancement of the pancreatic parenchyma was hypovascular in 12/12 patients. On quantitative image assessment, in group A patients, the mean diameter of duct stones was 0.6 mm (range 0-5 mm). Mean diameter of the main duct in the pancreatic head and body/tail was 4.8 mm and 4.9 mm, respectively. In group B patients, the mean diameter of duct stones was 21.9 mm (range 2-50 mm). Mean diameter of the main duct in the pancreatic head and body/tail was 18.8 mm and 13.9 mm, respectively. CONCLUSIONS|: In patients with GMAP and time interval between symptom onset and first CT scan ≤24 months (group A), CT identified normal or slightly increased parenchymal thickness and a main pancreatic duct of normal calibre and without duct stones. In contrast, in patients with GMAP and time interval between symptom onset and first CT scan >25 months (group B), it identified large-calibre duct stones with bull's-eye appearance.

[Parinaud's syndrome indicating imbalanced hydrocephalus in patients with cerebrospinal fluid shunts]. / Síndrome de Parinaud indicando hidrocéfalo descompensado em pacientes com derivação liquórica.

The cases of two patients with hypertensive hydrocephalus and Parinaud syndrome are reported. In both cases the ventriculographic studies showed a cystic expansion of the suprapineal recess. The upward gaze palsy was related with the expansion of the suprapineal recess. The radiological study of the posterior portion of the third ventricle in these cases is recommended. The use of inadequate devices in these situations may cause the worsing of the patient.