William G. Eversman

Urinary Tract Stones in Pregnancy

The presence of stones during an otherwise uneventful pregnancy is a dramatic and potentially serious issue for the mother, the fetus, and the treating physicians alike. The incidence and predisposing factors are generally the same as in nonpregnant, sexually active, childbearing women. Unique metabolic effects in pregnancy such as hyperuricuria and hypercalciuria, changes in inhibitors of lithiasis formation, stasis, relative dehydration, and the presence of infection all have an impact on stone formation. The anatomic changes and physiologic hydronephrosis of pregnancy make the diagnosis and treatment more challenging. Presenting signs and symptoms include colic, flank pain, hematuria, urinary tract infection, irritative voiding, fever, premature onset or cessation of labor, and pre-eclampsia. The initial evaluation and treatment are again similar to those used for the nonpregnant population. The most appropriate first-line test is renal ultrasonography, which may, by itself, allow the diagnosis to be made and provide enough information for treatment. Radiographic studies, including an appropriately performed excretory urogram, give specific information as to size and location of the stones, location of the kidneys, and differential renal function and can be used safely, but the ionizing radiation risks should be considered. All forms of treatment with the exception of extracorporeal shock wave lithotripsy and some medical procedures are appropriate in the pregnant patient. Close coordination by the urologist, the obstetrician, the pediatrician, the anesthesiologist, and the radiologist is required for the appropriate care of these patients.

US-guided Renal Transplant Biopsy: Efficacy of a Cortical Tangential Approach

PURPOSE To describe the cortical tangential approach to ultrasonographically (US) guided renal transplant biopsy and evaluate its efficacy in obtaining sufficient cortical tissue. MATERIALS AND METHODS This HIPAA-compliant retrospective study was exempted from review by the institutional review board. Informed consent was not required. The number of core biopsy samples, glomeruli, and small arteries obtained during 294 consecutive US-guided renal transplant biopsies in 254 patients (134 men, 120 women; age range, 19-79 years; mean age, 52.2 years) in one department between June 1 and December 31, 2008, were recorded, along with any ensuing complications. Procedural success was assessed according to Banff 97 criteria. RESULTS There were 1.2 +/- 0.4 (standard deviation) biopsy core samples taken per case by 11 radiologists using the cortical tangential approach. In 290 cases, biopsy results showed 21.7 +/- 10.1 glomeruli and 5.0 +/- 2.8 small arteries. Two hundred seventy-six (95%) cases were adequate or minimal according to Banff 97 assessment criteria. Of the 14 inadequate cases (5%), six were lacking only one glomerulus to achieve minimal status. Only one biopsy core sample was taken in all 14 inadequate cases and in 233 successful cases (success rate, 85%). None of the 43 cases with two or more biopsy core samples taken were inadequate (success rate, 100%). Two patients (0.7%) had a hemorrhagic complication requiring transfusion, and another four patients (1.4%) experienced a minor self-limiting complication. CONCLUSION The cortical tangential approach can be used by a cohort of radiologists to achieve 95% or higher collective success in obtaining cortical tissue during renal transplant biopsy, with few complications. The success rate is higher, without increased complications, when more than one core specimen is taken.

Performance and function of a desktop viewer at mayo clinic scottsdale

A clinical viewing system was integrated with the Mayo Clinic Scottsdale picture archiving and communication system (PACS) for providing images and the report as part of the electronic medical record (EMR). Key attributes of the viewer include a single user log-on, an integrated patient centric EMR image access for all ordered examinations, prefetching of the most recent prior examination of the same modality, and the ability to provide comparison of current and past exams at the same time on the display. Other functions included preset windows, measurement tools, and multiformat display. Images for the prior 12 months are stored on the clinical server and are viewable in less than a second. Images available on the desktop include all computed radiography (CR), chest, magnetic resonance images (MRI), computed tomography (CT), ultrasound (U/S), nuclear, angiographic, gastrointestinal (GI) digital spots, and portable C-arm digital spots. Ad hoc queries of examinations from PACS are possible for those patients whose image may not be on the clinical server, but whose images reside on the PACS archive (10TB). Clinician satisfaction was reported to be high, especially for those staff heavily dependent on timely access to images, as well as those having heavy film usage. The desktop viewer is used for resident access to images. It is also useful for teaching conferences with large-screen projection without film. We report on the measurements of functionality, reliability, and speed of image display with this application.

Contrast-enhanced Digital Mammography: A Single-Institution Experience of the First 208 Cases.

Contrast‐enhanced digital mammography (CEDM) is the only imaging modality that provides both (a) a high‐resolution, low‐energy image comparable to that of digital mammography and (b) a contrast‐enhanced image similar to that of magnetic resonance imaging. We report the initial 208 CEDM examinations performed for various clinical indications and provide illustrative case examples. Given its success in recent studies and our experience of CEDM primarily as a diagnostic adjunct, CEDM can potentially improve breast cancer detection by combining the low‐cost conclusions of screening mammography with the high sensitivity of magnetic resonance imaging.

Performance and function of a high-speed multiple star topology image management system at Mayo Clinic Scottsdale.

Mayo Clinic Scottsdale (MCS) is a busy outpatient facility (150,000 examinations per year) connected via asynchronous transfer mode (ATM; OC-3 155 MB/s) to a new Mayo Clinic Hospital (178 beds) located more than 12 miles distant. A primary care facility staffed by radiology lies roughly halfway between the hospital and clinic connected to both. Installed at each of the three locations is a high-speed star topology image network providing direct fiber connection (160 MB/s) from the local image storage unit (ISU) to the local radiology and clinical workstations. The clinic has 22 workstations in its star, the hospital has 13, and the primary care practice has two. In response to Mayo’s request for a seamless service among the three locations, the vendor (GE Medical Systems, Milwaukee, WI) provided enhanced connectivity capability in a two-step process. First, a transfer gateway (TGW) was installed, tested, and implemented to provide the needed communication of the examinations generated at the three sites. Any examinations generated at either the hospital or the primary care facility (specified as the remote stars) automatically transfer their images to the ISU at the clinic. Permanent storage (Kodak optical jukebox, Rochester, NY) is only connected to the hub (Clinic) star. Thus, the hub ISU is provided with a copy of all examinations, while the two remote ISUs maintain local exams. Prefetching from the archive is intelligently accomplished during the off hours only to the hub star, thus providing the remote stars with network dependent access to comparison images. Image transfer is possible via remote log-on. The second step was the installation of an image transfer server (ITS) to replace the slower Digital Imaging and Communications in Medicine (DICOM)-based TGW, and a central higher performance database to replace the multiple database environment. This topology provides an enterprise view of the images at the three locations, while maintaining the high-speed performance of the local star connection to what is now called the short-term storage (STS). Performance was measured and 25 chest examinations (17 MB each) transferred in just over 4 minutes. Integration of the radiology information management system (RIMS) was modified to provide location-specific report and examination interfaces, thereby allowing local filtering of the worklist to remote and near real-time consultation, and remote examination monitoring of modalities are addressed with this technologic approach. The installation of the single database ITS environment has occurred for testing prior to implementation.

May-Thurner: diagnosis and endovascular management

Common left iliac vein compression, otherwise known as May-Thurner (MT), is an anatomical risk factor for lower extremity deep vein thrombosis (DVT). MT refers to chronic compression of the left iliac vein against the lumbar spine by the overlying right common iliac artery. The compression may be asymptomatic. The syndrome is a clinical spectrum of physical findings and history plus the lesion. It is characterized by the varying degrees of venous hypertension. This can be non-thrombotic, combined with acute DVT or post-thrombotic. Traditionally, acute DVT was treated with standard anticoagulation and sometimes, thrombectomy. However these measures do not address the underlying culprit lesion of mechanical compression. Furthermore, if managed only with anticoagulation, patients with residual thrombus are at risk for developing recurrent DVT or post-thrombotic syndrome (PTS). Both retrospective and prospective studies have shown that endovascular management should be the preferred approach to dissolve proximal thrombus and to also treat the underlying compression with endovascular stent placement.

Factors Contributing to the Success of Ultrasound-Guided Native Renal Biopsy

The purpose of this study was to evaluate factors contributing to the success of ultrasound‐guided native renal biopsy.

Rationale for catheter directed therapy in pulmonary embolism

Pulmonary embolism (PE) is a widespread health concern associated with major morbidity and mortality. Catheter directed therapy (CDT) has emerged as a treatment option for acute PE adding to the current potential options of systemic thrombolysis or anticoagulation. The purpose of this review is to understand the rationale and indications for CDT in patients with PE. While numerous studies have shown the benefits of systemic thrombolysis compared to standard anticoagulation, these are balanced by the increased risk of major bleeding. With this in mind, CDT has the potential to offer the benefits of systemic thrombolysis and in theory, a reduced risk of bleeding. This article will review current treatment guidelines in both massive and submassive PE evaluating both short and long term benefits. The role of CDT will be highlighted, with an emphasis on efficacy and safety.

Ureteroarterial Fistula Following Laser Endopyelotomy

uratio A 29-year-old female underwent robot assisted pyeloplasty with subsequent failure 5 weeks after surgery. Six weeks after stent placement for acute obstruction ureteroscopy revealed a short stricture at the anastomotic site. The decision was made to perform laser endopyelotomy under direct vision rather than using a cutting endopyelotomy balloon because we were already visualizing the stricture. No pulsations were identified and no bleeding was encountered. The patient resumed vigorous exercise and went hiking 2 weeks after surgery. Within 24 hours she had gross hematuria. Computerized tomography only confirmed blood within the collecting system and the bleeding ceased with bed rest. Ureteroscopy revealed pinpoint pulsatile bleeding coming from the previous endopyelotomy site. A ret-

Initial Experience of Tomosynthesis-Guided Vacuum-Assisted Biopsies of Tomosynthesis-Detected (2D Mammography and Ultrasound Occult) Architectural Distortions

OBJECTIVE As experience and aptitude in digital breast tomosynthesis (DBT) have increased, radiologists are seeing more areas of architectural distortion (AD) on DBT images compared with standard 2D mammograms. The purpose of this study is to report our experience using tomosynthesis-guided vacuum-assisted biopsies (VABs) for ADs that were occult at 2D mammography and ultrasound and to analyze the positive predictive value for malignancy. MATERIALS AND METHODS We performed a retrospective review of 34 DBT-detected ADs that were occult at mammography and ultrasound. RESULTS We found a positive predictive value of 26% (nine malignancies in 34 lesions). Eight of the malignancies were invasive and one was ductal carcinoma in situ. The invasive cancers were grade 1 (4/8; 50%), grade 2 (2/8; 25%), or grade 3 (1/8; 13%); information about one invasive cancer was not available. The mean size of the invasive cancers at pathologic examination was 7.5 mm (range, 6-30 mm). CONCLUSION Tomosynthesis-guided VAB is a feasible method to sample ADs that are occult at 2D mammography and ultrasound. Tomosynthesis-guided VAB is a minimally invasive method that detected a significant number of carcinomas, most of which were grade 1 cancers. Further studies are needed.