May-Thurner syndrome: can it be diagnosed by a single MR venography study?

PURPOSEWe aimed to evaluate the longitudinal stability of left common iliac vein (LCIV) compression by the right common iliac artery on magnetic resonance venography (MRV). MATERIALS AND METHODSThis retrospective study included 214 patients diagnosed with May-Thurner syndrome by MRV. We identi‘ed a subset of patients who underwent contrast-enhanced cross-sectional imaging of the pelvis six months before or anytime after the MRV and did not undergo any interventional venous procedures between the two studies; 36 patients met these criteria. The degree of venous compression was calculated in both the index and comparison study. RESULTSOn the index MRV, the mean compression of the LCIV was 62%. However, on the comparis on study in the same patients, the mean compression was 39%. The mean change in degree of compression between the two studies was 23% (P < 0.0001), ranging from a 12% increase to 69% decrease in degree of compression on the comparison study. CONCLUSIONThe compressed LCIV on a single MRV study was not stable over time and thus may be insuf‘cient to diagnose MayThurner syndrome

Palliative gastrostomy in the setting of voluminous ascites

Objective: We report the indications, methods, and complications of percutaneous gastrostomy/gastrojejunostomy (G/GJ) in patients with voluminous ascites. Methods: Following institutional review board approval, 69 patients (14 male, 55 female, mean age 58±12 years, range 32–89 years) who underwent percutaneous G/GJ with paracentesis were identified from a prospectively acquired database. Electronic medical record data extracted included diagnosis, method of G/GJ insertion, clinical course, and complications, which were graded by The Society of Interventional Radiology (SIR) criteria. Statistics were performed using Graphpad Instat. Results: Sixty-six G and three GJ catheters were placed in 62 patients with malignant and 7 patients with benign disease; 47 procedures were conducted using fluoroscopy and 22 using computed tomography (CT; 10 patients had failed fluoroscopy). Sixty-six patients had 1980±1371 mL (range, 20–5000 mL) ascites drained (more in males, p=0.01) 0.8±1.6 days (range, 0–5 days) prior to placement. Forty-one patients had significantly less ascites (1895±1426 mL; range, 100–5400 mL) drained after G/GJ (p>0.0.5). Mean survival after insertion was 43±57 days (range, 1–252 days) among 38 patients for whom data were available. Fifty-six patients had a mean postprocedure hospital stay of 8.6±8.4 days (range, 0–45 days); 3 were outpatients and 10 patients died in the hospital. Successful gastropexy was confirmed on subsequent cross-sectional imaging in 22 of 25 patients. There were 25 tube maintenance issues that included catheter displacement and leakage, one patient experienced hemorrhage, and there were two deaths. All except one patient had satisfactory gastrostomy function. Conclusion: Effective G/GJ placement is possible in most patients with voluminous ascites provided ascites is drained and gastrocutaneous fistula formation occurs. Caution is advised; placement is generally for fragile terminal patients, and fluoroscopy or CT guidance is required

Feasibility and accuracy of CT-guided percutaneous needle biopsy of cavitary pulmonary lesions

PURPOSEWe aimed to evaluate the feasibility, accuracy, and complications of computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) of cavitary lesions.METHODSConsecutive PTNB procedures in an academic institution over a 4-year period were reviewed, 53 of which were performed on patients with cavitary lesions. The demographic data of patients, lesion characteristics, biopsy technique and complications, initial pathologic results, and final diagnosis were reviewed. A final diagnosis was established through surgical correlation, microbiology or clinico-radiologic follow-up for at least 18 months after biopsy.RESULTSThe overall accuracy of PTNB was 81%. In 33 patients (62%) the cavitary lesion was found to be malignant (23 lung cancers and 10 metastases). The sensitivity and specificity for malignancy was 91% and 100%, respectively. In 20 patients (38%) a benign etiology was established (16 infections and 4 noninfectious etiologies), with PTNB demonstrating a sensitivity of 81% and specificity of 100% for infection. Wall thickness at the biopsy site, lesion in lower lobe, and malignancy were significant independent risk factors for diagnostic success. Minor complications occurred in 28% of cases: 13 pneumothoraces (5 requiring chest tube), 1 small hemothorax, and 1 mild hemoptysis. A nonsignificant higher chest tube insertion rate was seen in cavities with a thinner wall.CONCLUSIONPTNB of cavitary lesions provides high accuracy, sensitivity, and specificity for both malignancy and infection and has an acceptable complication rate. Wall thickness at the biopsy site, lesion in lower lobe, and malignancy were significant independent risk factors for diagnostic success. Samples for microbiology should be obtained in all patients, especially in the absence of on-site cytology, due to the high prevalence of infection in cavitary lesions

Magnetic Nanoparticles in the Imaging of Tumor Angiogenesis

Angiogenesis, the growth of new capillary blood vessels, is central to the growth of tumors. Non-invasive imaging of tumor angiogenesis will allow for earlier detection of tumors and also the development of surrogate markers for assessing response to treatment. Steady state magnetic resonance imaging with magnetic nanoparticles is one method to assess angiogenesis. In this article we explain the theory behind steady state magnetic resonance imaging and review the available literature

MR imaging of malignancies arising in endometriomas and extraovarian endometriosis

Cancers that arise in ovarian or extraovarian endometriosis are a distinct disease category with a histologic profile different from that of the more common epithelial ovarian cancers and with a better prognosis. Because the malignant transformation of endometriomas is rarely associated with lymphadenopathy or peritoneal carcinomatosis, a high index of suspicion on the part of the radiologist is necessary to establish a timely diagnosis of endometriosis-related ovarian cancers and allow appropriate oncologic management. Although imaging is not currently performed for surveillance of endometriosis, magnetic resonance (MR) imaging is often performed when surgical treatment is under consideration. An optimal MR imaging protocol for the detection of cancer arising in an endometrioma includes a review of subtraction images derived from unenhanced and contrast material-enhanced T1-weighted datasets. Subtraction images provide improved conspicuity of enhancing mural nodules-which are the most sensitive MR imaging sign of malignancy in ovarian endometriosis- against the background of the high-signal-intensity endometriotic cyst. Cancers arising in extraovarian endometriosis typically manifest as solid lesions with intermediate signal intensity on T1-and T2-weighted images, enhancement after the intravenous administration of a gadolinium- based contrast material, and restricted diffusion on diffusion-weighted images and apparent diffusion coefficient (ADC) maps. The signal intensity of myometrium, or, if the uterus is absent, that of the small bowel wall, is used as an internal reference standard for lesion signal intensity. Lesions are considered to have restricted diffusion if they show signal hyperintensity relative to the reference structure on diffusion-weighted images and hypointensity or isointensity relative to that structure on ADC maps. For definitive diagnosis, histopathologic analysis is required. (C) RSNA, 2012 . radiographics.rsna.or

Investigation of cardiomyopathy using cardiac magnetic resonance imaging part 2: Rare phenotypes

Cardiac magnetic resonance imaging (CMRI) has emerged as a useful tertiary imaging tool in the investigation of patients suspected of many different types of cardiomyopathies. CMRI images are now of a sufficiently robust quality to enable high spatial and temporal resolution image acquisition. This has led to CMRI becoming an effective non-invasive imaging tool for many cardiomyopathies. In this two-part review we outline the typical sequences used to image cardiomyopathy and present the imaging spectrum of cardiomyopathy. Part I focused on the current classification of cardiomyopathy, the basic CMRI sequences used in evaluating cardiomyopathy and the imaging spectrum of common phenotypes. Part II illustrates the imaging spectrum of the more rare phenotypes