Continent urinary diversions: review of current surgical procedures and radiologic imaging

Continent urinary diversions are currently gaining wide acceptance as alternatives to the ileal conduit following cystectomy for neoplasm or bladder dysfunction. Clean, intermittent catheterization of the reservoir (pouch) at regular intervals obviates the inconvenience of wearing an external stomal appliance. A variety of surgical techniques have been described for continent pouches. These techniques make use of the small bowel alone (Camey and Kock techniques) or a combination of cecum and terminal ileum (Indiana, Mainz, Penn, and King techniques). The optimum pouch protects the upper tracts by prevention of reflux, provides urinary continence, and has sufficient capacity to require catheterization no more frequently than every 3-6 hours. Simplified construction techniques for the commonly encountered pouches are graphically presented, and a method is suggested for the study of continent diversions.     

Radiography of cutaneous urinary diversions

Imaging of cutaneous urinary diversions (CUDs) requires the use of special radiographic procedures. This article describes the techniques for radiographic examination of the two major types of CUDs: urinary conduits and continent urinary reservoirs. Diagrams and radiographs depict the structure and function of these urinary diversions. A Quick Procedural Reference guide is included to allow easy introduction of the examination protocols into a radiology department's procedure manual.     

Imaging of the various continent urinary diversions after cystectomy

Continent urinary diversions have recently become the preferred procedures rather than performing an ileal conduit. Intravenous urography, pouchography, and computed tomography scans are frequently used for postoperative evaluation of patients with bladder carcinoma. During postoperative follow-up imaging studies, the radiologist must keep these 4 facets in mind as his primary focus: 1) the detection of newly developed urothelial tumors, 2) the detection of metastasis, 3) the detection of postoperative complications, and 4) the monitoring of upper urinary tract distention. Various surgical techniques that are used in continent diversions alter the normal anatomy and make the imaging interpretation difficult. An accurate interpretation can be made only if radiologists become familiar with the various surgical procedures and the appearances of various postoperative anatomic changes.     

Cardiovascular molecular imaging: the road ahead

Despite significant advancements in medical and device-based therapies, cardiovascular disease remains the number one cause of death in the United States. Early detection of atherosclerosis, prevention of myocardial infarction and sudden cardiac death, and modulation of adverse ventricular remodeling still remain elusive goals. Molecular imaging focuses on identifying critical cellular and molecular targets and therefore plays an integral role in understanding these biologic processes in vivo. Because many imaging targets are upregulated before irreversible tissue damage occurs, early detection could ultimately lead to development of novel, preventive therapeutic strategies. This review addresses recent work on radionuclide imaging of cardiovascular inflammation, infection, and infarct healing. We further discuss opportunities provided by multimodality approaches such as PET/MRI and PET/optical imaging.     

Brucellosis: appearance on skeletal imaging

Brucellosis is an endemic disease in the Middle East. Its incidence in Kuwait has increased during the last 5 years. Bone and joint involvement causes major symptoms and disabilities. Radionuclide bone scans are more sensitive than radiographs in detecting these lesions. The aim of this study is to describe the abnormal patterns detected on bone imaging in acute and chronic brucellosis. Tc-99m MDP bone scans of 56 patients with established diagnosis of brucellosis (19 acute and 37 chronic) were retrospectively analyzed. Bone scans were positive in 8 of 19 patients (42%) with acute brucellosis and in 28 of 37 patients (76%) with chronic brucellosis. Six patterns were observed: involvement of an entire body of one or more vertebrae, especially at the lumbar region (50%); sacroiliitis (41%); focal high uptake at the junction of the upper and lateral margins of the vertebra "Caries sign" (27%); multiple costovertebral joints and costochondral junction involvement (19%); involvement of large joints similar to degenerative osteoarthritis (25%); and focal involvement of long bone (11%).     

Wooden foreign bodies: imaging appearance

OBJECTIVE: The purpose of this study was to identify the characteristic imaging features of wooden foreign bodies. MATERIALS AND METHODS: The imaging studies of 12 patients with surgically confirmed wooden foreign bodies were retrospectively reviewed. The study group consisted of seven females and five males, 10-65 years old (mean age, 36 years). All patients underwent radiography. Nine patients were evaluated with sonography, eight with MR imaging, three with CT, and one with CT arthrography. Gadolinium-enhanced MR imaging was performed in six patients. Three patients presented with a draining sinus and nine with painful swelling. Only three patients presented with a history of penetrating injury. RESULTS: Lesions were located in the foot (n = 4), hand (n = 3), thigh (n = 2), calf (n = 2), and elbow (n = 1). Radiographs failed to reveal the retained foreign bodies in all patients. With MR imaging, wooden foreign bodies displayed a variable signal intensity that was equal to or less than that of skeletal muscle on both T1- and T2-weighted images. MR imaging showed the surrounding inflammatory response in all patients. CT showed the retained wood as linear cylindric foci of increased attenuation. Wood was highly echogenic and revealed pronounced acoustic shadowing on sonography. Arthrography in one patient showed an associated reactive synovitis. CONCLUSION: The imaging appearance of wooden foreign bodies is variable; however, imaging can be quite specific, and when taken in the appropriate clinical setting, the imaging should reliably suggest the diagnosis. Sonography is frequently underused but proved most useful for the evaluation of retained wooden foreign bodies.     

Orbital imaging: factors determining magnetic resonance imaging appearance

This article addresses the dependence of the image characteristics in MR imaging of the orbit. Among the variables discussed are signal-to-noise (SNR), field of view (FOV), spatial resolution, and their interdependence. It is further shown how image contrast can be controlled by judicious choice of pulse timing parameters and how contrast depends on the intrinsic tissue MR parameters T1, T2, and proton density.     

Endometriosis: appearance and detection at MR imaging

Thirty-nine magnetic resonance (MR) studies were performed on 31 women with surgically proved endometriosis. A total of 88 endometriotic lesions ranging in size from 0.2 to 7.5 cm were detected on 24 of 30 MR images of women. The signal intensities ranged from hyperintense on all pulse sequences (41 of 88) to hypointense on all sequences (24 of 88); the remainder demonstrated signal intensities corresponding to the appearances of acute, subacute, and chronic hematomas. Hypointense or signal-void rims on both T1- and T2-weighted images were detected in 35 lesions. Identification of the disease with MR imaging versus concurrent surgery was compared for 76 sites in 19 patients. Findings were true-positive in 24 cases, false-negative in ten, true-negative in 32, and false-positive in seven, resulting in an MR sensitivity of 71% and specificity of 82%. Adhesions obscured the disease at laparoscopy in three patients. MR imaging cannot be used as a substitute for laparoscopy in the definitive diagnosis or staging of endometriosis. However, it can be used to monitor treatment response in place of laparoscopy once a diagnosis is firmly established.     

Prosthetic testicle: appearance at MR imaging

The appearance of testicular prostheses on magnetic resonance (MR) images was studied in six patients with seven silicone implants: two with a fluid consistency and five that were solid. On T1-weighted images, both types of prosthesis demonstrated homogeneous low signal intensity; on T2-weighted images, the fluid implants had a uniformly low signal intensity, and the solid implants had a uniformly high signal intensity. Both prostheses created a chemical shift artifact on all imaging sequences owing to the difference in chemical composition of the prostheses and the surrounding tissue.     

Duodenal duplication cyst: MR imaging appearance

The MR imaging appearance of a duodenal duplication cyst is reported. MR imaging confirmed the diagnosis suggested by ultrasound and CT scans. Fat-suppressed MR imaging before and after oral administration of the positive contrast agent Gd-DTPA was able to define tissue planes between the lesion and adjacent structures, such as the head of the pancreas, providing useful information for an accurate surgical approach. To our knowledge this is the first reported case of a duodenal duplication cyst in an adult demonstrated by MR imaging. Received: 23 February 1998; Revision received: 22 July 1998; Accepted: 25 July 1998     

Recurrent biliary cystadenoma: MR imaging appearance

The authors report the case of a 37-year-old woman with a biliary cystadenoma that mimicked a liver cyst. The magnetic resonance (MR) imaging features of this rare lesion were correlated with the pathologic findings, showing the potential of MR imaging for depicting and aiding in the diagnosis of biliary cystadenoma and its recurrence.     

Cranial postoperative site: MR imaging appearance

The ability to diagnose adverse postcraniotomy or postcraniectomy events is essential for proper postoperative care. The importance of identifying postoperative changes on CT has previously been shown. The purpose of this study is to assess the normal and abnormal MR changes that may be seen in the postcraniotomy/postcraniectomy period. The postoperative MR, CT, and medical records of 41 postcraniotomy patients and 26 postcraniectomy patients were reviewed. Reasons for choosing craniectomy over craniotomy included decompression, infected flap, bony involvement by tumor, and posttraumatic skull. In general, the postoperative normal anatomy was better seen with MR. Postoperative events included hemorrhage (two), infection (five), cyst formation (10), and recurrent tumor (five). In general, MR was found to be more useful than CT for the detection of hemorrhage and infection after craniotomy or craniectomy and for the proper localization of postoperative cysts. MR proved to be a useful method for following postoperative sites in the skull.     

Aesthetic surgery of the buttocks: imaging appearance

Familiarity with the imaging appearance and potential complications of buttocks aesthetic surgery is important for radiologists. In this review, we illustrate the spectrum of imaging features after buttocks implants, liposuction, fat injections and silicone injections. Complications such as fat necrosis, abscess, and silicone migration are also presented.     

Radiologic evaluation of continent urinary reservoirs

A variety of methods are currently used for urinary diversion after cystectomy in adults. Radiologists are generally familiar with ileal and colonic conduits but are less familiar with the recently popularized continent urinary reservoirs. We describe and illustrate the surgical technique, normal anatomy, and normal radiographic appearance of a variety of urinary reservoirs, including the Kock pouch, Camey procedure, and various ileocecal reservoirs. Complications of various reservoirs are also discussed and illustrated.     

骨纤维囊性骨炎影像学表现与病理分析

目的:探讨骨纤维囊性骨炎的影像学表现及病理特点。方法:12例患者中男5例,女7例;年龄18～47岁;X线检查12例,CT检查6例,MRI检查2例,骨扫描1例。结果:12例均为多骨多病灶骨炎。以骨盆骨、颅骨多见,上下肢骨、肋骨、脊柱骨次之。X线片及CT图像上以囊样骨质破坏为主,呈单囊或多囊,病灶可有膨胀;边界有硬化边;皮质变薄,可有缺失;无软组织肿块生成;无骨膜增生;部分发生病理骨折。颅骨病灶可呈类圆形团絮状密度增高影。MRI表现为T1WI呈低信号,T2WI呈稍高信号,内可有小类圆形液体高信号。病灶直径大小不一,以0.5～3 cm居多,形成棕色瘤。病理以纤维组织为主,周围有骨样组织,棕色瘤者有多核巨细胞和吞噬细胞。结论:本病影像学和病理表现具有相对特征性,临床、影像、病理三者结合可减少误诊;切除甲状旁腺病变后,骨骼病变大多可逐渐恢复功能。