Nonlesional Sources of Contrast Enhancement on Postgadolinium "Black-Blood" 3D T1-SPACE Images in Patients with Multiple Sclerosis.

BACKGROUND AND PURPOSE: We hypothesized that 3D T1-TSE "black-blood" images may carry an increased risk of contrast-enhancing lesion misdiagnosis in patients with MS because of the misinterpretation of intraparenchymal vein enhancement. Thus, the occurrence of true-positive and false-positive findings was compared between standard MPRAGE and volumetric interpolated brain examination techniques. MATERIALS AND METHODS: Sampling perfection with application-optimized contrasts by using different flip-angle evolution (SPACE) images obtained from 232 patients with MS, clinically isolated syndrome, or radiologically isolated syndrome were compared with standard MPRAGE and volumetric interpolated brain examination images. The intraparenchymal vein contrast-to-noise ratio was estimated at the level of the thalami. Contrast-enhancing lesions were blindly detected by 2 expert readers and 1 beginner reader. True- and false-positives were determined by senior readers' consensus. True-positive and false-positive frequency differences and patient-level diagnosis probability were tested with the McNemar test and OR. The contrast-to-noise ratio and morphology were compared using the Mann-Whitney U and χ2 tests. RESULTS: The intraparenchymal vein contrast-to-noise ratio was higher in SPACE than in MPRAGE and volumetric interpolated brain examination images (P < .001, both). There were 66 true-positives and 74 false-positives overall. SPACE detected more true-positive and false-positive results (P range < .001-.07) but did not increase the patient's true-positive likelihood (OR = 1 1.29, P = .478-1). However, the false-positive likelihood was increased (OR = 3.03-3.55, P = .008-.027). Venous-origin false-positives (n = 59) with contrast-to-noise ratio and morphology features similar to small-sized (≤14 mm3 P = .544) true-positives occurred more frequently in SPACE images (P < .001). CONCLUSIONS: Small intraparenchymal veins may confound the diagnosis of enhancing lesions on postgadolinium black-blood SPACE images.

Selective arterial embolisation for bone tumours: experience of 454 cases.

PURPOSE: The authors present the experience of a single institution with selective arterial embolisation for primary and metastatic bone tumours. MATERIALS AND METHODS: A total of 365 patients were treated with 454 embolisation procedures from December 2002 to April 2010. Embolisation was the primary treatment for benign bone tumours, adjuvant treatment to surgery for benign and malignant bone tumours and palliative treatment for bone sarcomas and metastases. Indications for repeat embolisation included pain or imaging evidence of progressive disease: 105 patients had repeat embolisation at the same location at an interval of 1-3 months; 260 patients had one embolisation, 78 had two and 29 had three or more. In all patients, N-2-butyl cyanoacrylate (NBCA) in 33% lipiodol was the embolic agent used. RESULTS: A total of 419 of the 454 embolisations (93%) were technically successful. In 35 cases, embolisation was not feasible because of poor lesion vascularisation (21 patients with bone metastases and two with aneurysmal bone cysts), origin of the Adamkiewicz artery in the embolisation field (four patients with bone metastases and one with aneurysmal bone cyst), atheromatosis and arteriosclerosis (five patients with bone metastases) and anatomical and technical problems such as small-calibre vessels, many branches and acute vessel angles (two patients with bone metastases). A clinical response was achieved in 406 of the 419 procedures (97%), and no response in 13 procedures in patients with pelvis and sacrum tumours. Complications included postembolisation syndrome in 81 patients (22%), transient paraesthesias in 41 (11%), skin breakdown and subcutaneous necrosis at the shoulder and pelvis in five (1.4%) and paresis of the sciatic nerve in one (0.3%). CONCLUSIONS: We recommend embolisation as primary or palliative treatment or an adjunct to surgery for tumours of variable histology. Strict adherence to the principles of transcatheter embolisation is important. Arteries feeding the tumour and collaterals must be evaluated carefully and catheterised superselectively to protect the normal tissues. NBCA is considered the most appropriate embolic agent for small-vessel occlusion without major complications.

High-resolution computed tomography in the diagnosis and follow-up of idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is the most common interstitial lung disease and is associated with a fatal prognosis. Familiarity with the typical appearances of IPF on high-resolution computed tomography (HRCT) is important, as in the appropriate clinical setting, it is often sufficient for establishing a confident diagnosis of IPF without the need for surgical biopsy. Moreover, HRCT can provide important prognostic information in IPF. This is noteworthy, as the course of IPF is variable, and many patients develop complications leading to respiratory failure and death. The purpose of this paper is to review the progress made towards a better understanding of the HRCT patterns of IPF.

Three-dimensional analysis of pulmonary nodules: variability of semiautomated volume measurements between different versions of the same software.

PURPOSE: This study was done to evaluate the variability of semiautomated volume measurements of solid pulmonary nodules between two different versions of the same volumetric software. MATERIALS AND METHODS: The volumes of 100 solid intraparenchymal nodules (mean volume 88.10 mm(3); range 7.36-595.25 mm(3)) studied with the same multidetector computed tomography (MDCT) protocol were determined using two different versions of the same volumetric software (LungCARE 2006G and LungCARE 2007S). The 2006G version is based on a single-segmentation algorithm, whereas the newer version features two algorithms: SmallSizeNodule and AllSizeNodule. The results obtained with the 2006G version were compared with those of the 2007S version with the SmallSizeNodule algorithm, as recommended by the user manual. In addition, we compared the volumetric measurements obtained by the two different algorithms of the 2007S version. RESULTS: The 2006G version and the 2007S version with the SmallSizeNodule algorithm agreed in only two of 100 cases and showed a mean variability of 1.66% (range 0%-8.78%). A more significant volumetric discrepancy was observed between the two different algorithms of the 2007S version, with the AllSizeNodule algorithm providing on average larger volumes (mean variability 71.08%; range 6.02%-218.80%) than SmallSizeNodule. Volume discrepancies were more pronounced in the subgroups of smaller nodules in all comparisons. CONCLUSIONS: There is variability also in the results provided by different versions of the same volumetric software, and this may affect the calculation of the nodule-doubling time. Computer-aided assessment of the growth of lung nodules should always be performed using the same version of volumetric software and the same segmentation algorithm.

Transmigrated intrauterine device discovered 17 years after its insertion.

We present the case of an intraperitoneal IUD incidentally noted on lumbar spine X-rays and confirmed by CT. This was secondary to asymptomatic uterine perforation occurred at the time of insertion 17 years before.

Urinary ascites due to retroperitoneal fibrosis: a case report.

Urinary ascites in adults is usually secondary to iatrogenic or traumatic injuries. A case of a 69-year-old male with abdominal pain and decreased renal function is described. Ultrasound showed bilateral hydronephrosis and ascites. Computed tomography revealed retroperitoneal fibrosis complicated by a rupture at the right ureteropelvic junction and urine extravasation in the perirenal and intraperitoneal spaces. Delayed scans showed leaking of contrast media from the anterior perirenal space to the peritoneal cavity. The urinary ascites resolved using a double-J stent.