Imaging malignant and apparent malignant transformation of benign gynaecological disease.

Common benign gynaecological diseases, such as leiomyoma, adenomyosis, endometriosis, and mature teratoma, rarely undergo malignant transformation. Benign transformations that may mimic malignancy include benign metastasizing leiomyoma, massive ovarian oedema, decidualization of endometrioma, and rupture of mature teratoma. The aim of this review is to provide a contemporary overview of imaging findings in malignant and apparent malignant transformation of benign gynaecological disease.

Case report: Renal replacement lipomatosis associated with renal transplantation.

We report a case of extensive renal replacement lipomatosis demonstrated by ultrasound (US) and computed tomography (CT) in a 57-year-old woman with a history of two cadaveric renal transplants. One transplant was non-functional due to chronic rejection. The second renal transplant is functioning normally and the renal replacement lipomatosis did not cause mass effect on either of the renal transplants.

Imaging of hepatocellular carcinoma: a practical approach.

Imaging of hepatocellular carcinoma (HCC) is complicated because the tumor has a varied radiologic appearance and frequently coexists with cirrhotic regenerative and dysplastic nodules. In cirrhotic patients, any dominant solid nodule that is not clearly a hemangioma should be considered a HCC until proven otherwise, especially if the lesion is hypervascular, of high T2 signal intensity, or demonstrates venous invasion. Biopsy of HCC in cirrhosis is risky and surveillance is often preferable. The doubling time of HCC is 1 to 12 months, and a nodule that is stable over 4 months is very unlikely to be a HCC. However, stable nodules cannot be dismissed, since livers containing dysplastic nodules are at high risk to develop HCC. In noncirrhotic patients, any solid mass that is not clearly a hemangioma or focal nodular hyperplasia is potentially a HCC, and biopsy may be required. Venous invasion by tumor should be distinguished from bland thrombus. Imaging detection of nodal metastases is limited by the frequent finding of benign reactive lymphadenopathy in cirrhosis. Resection is the preferred treatment for HCC, but is contraindicated in the presence of tumors in both lobes, major venous invasion, invasion of adjacent organs other than the gallbladder, tumor rupture, nodal metastases, or distant metastases.

Technique for construction of an in vivo model of simulated pulmonary metastases.

RATIONALE AND OBJECTIVES: Existing methods used to simulate pulmonary metastases are unsatisfactory. The aim of this study was to create a simple in vivo model of pulmonary metastases by endobronchial deployment of small high-density beads in anesthetized dogs. METHODS: Commercially available decorative beads measuring 2 and 4 mm in diameter and of high density (600 to 1200 Hounsfield units) were deployed in the peripheral airways of anesthetized dogs using catheter and guide wire manipulations through an endotracheal tube. RESULTS: A total of 65 beads were placed in five dogs. Computed tomography demonstrated that 41 (63%) were satisfactorily located in the lung periphery, 9 (14%) were unsatisfactorily located in large airways, and 15 (23%) were not visible. CONCLUSIONS: The endobronchial deployment of small high-density beads in the peripheral airways of anesthetized dogs is a novel and effective technique for creation of an in vivo model of pulmonary metastases.

Inconclusive clinical and ultrasound evaluation of the scrotum: impact of magnetic resonance imaging on patient management and cost.

OBJECTIVES: To determine the diagnostic utility and net cost of magnetic resonance imaging (MRI) in the management of clinically and sonographically inconclusive scrotal lesions. METHODS: A multicenter retrospective review identified 34 patients diagnosed with scrotal MRI following inconclusive clinical and ultrasound (US) evaluation. Final diagnoses were based on surgery (n = 18) or clinical and US follow-up (n = 16). Final diagnoses of 29 testicular lesions were as follows: orchitis (n = 11), infarct (n = 6), neoplasm (n = 6), rupture (n = 3), torsion (n = 2), and radiation fibrosis (n = 1). Final diagnoses of five extratesticular lesions were as follows: epididymitis (n = 2), epididymal abscess (n = 2), and neoplasm (n = 1). Management plans prior to and following MRI findings were formulated by a general urologist and a urologic oncologist. The costs of the pre-MRI and post-MRI management plans were estimated using the Medicare reimbursement schedule. RESULTS: The leading US diagnosis was correct for 10 of 34 patients (29%) and the leading MRI diagnosis was correct for 31 of 34 patients (91%). MRI improved the management plan of the general urologist and urologic oncologist in 19 patients (56%) and 17 patients (50%), respectively. MRI worsened the management plan of both clinicians in 1 patient. Management was unchanged in all other patients. The overall net cost savings were $543 to $730 per patient for the urologic oncologist and the general urologist, respectively, and $3833 per patient originally scheduled for surgery. CONCLUSIONS: Use of MRI after inconclusive clinical and US evaluation of scrotal lesions may improve management, decrease the number of surgical procedures, and result in net cost savings.

Fast MR imaging of fetal CNS anomalies in utero.

BACKGROUND AND PURPOSE: Although sonography is the primary imaging technique for evaluating the developing fetus, significant limitations exist in the sonographic prenatal diagnosis of many brain disorders. Fast MR imaging is increasingly being used to determine the underlying cause of nonspecific fetal CNS abnormalities detected sonographically and to confirm or provide further support for such anomalies. Our goal was to determine the value of MR imaging in establishing the diagnosis of fetal CNS anomalies, to ascertain how this information might be used for patient counseling, and to assess its impact on pregnancy management. METHODS: We prospectively performed MR examinations of 73 fetuses (66 pregnancies) with suspected CNS abnormalities and compared these with available fetal sonograms, postnatal images, and clinical examinations. Retrospectively, the impact on patient counseling and pregnancy management was analyzed. RESULTS: Images of diagnostic quality were routinely obtained with in utero MR imaging, which was particularly valuable in detecting heterotopia, callosal anomalies, and posterior fossa malformations, and for providing excellent anatomic information. We believe that 24 (46%) of 52 clinical cases were managed differently from the way they would have been on the basis of sonographic findings alone. In every case, the referring physicians thought that MR imaging provided a measure of confidence that was not previously available and that was valuable for counseling patients and for making more informed decisions. CONCLUSION: Sonography is the leading technique for fetal assessment and provides reliable, inexpensive diagnostic images. Fast MR imaging is an important adjunctive tool for prenatal imaging in those instances in which a complex anomaly is suspected by sonography, when fetal surgery is contemplated, or when a definitive diagnosis cannot be determined.

Imaging and management of atypical testicular masses.

Most testicular masses are germ cell malignancies and require radical orchiectomy. There are other causes of testicular masses, however, some of which have characteristic imaging and clinical features. A presumptive diagnosis may be possible for some of these atypical testicular masses. This may result in testis-preserving surgery or nonoperative management.

Benign prostatic hyperplasia: clinical overview and value of diagnostic imaging.

The term benign prostatic hyperplasia has traditionally been used to describe a constellation of obstructive and irritative voiding symptoms that occur in men as they age. Such symptomatology may be due to a variety of causes, including prostatic enlargement. Thus, the term lower urinary tract symptoms has replaced BPH to describe this symptom complex. The evaluation and treatment of LUTS continues to be a significant part of urology practice in the United States, as well as a significant component of medical resource utilization. Currently, indication for treatment in patients with LUTS is most often based on subjective measurements of symptom severity and bother. Consequently, imaging does not play a major role in the evaluation of such patients. Recent data suggest that the size of the prostate gland may predict which patients with LUTS will develop progressive symptoms and complications. Moreover, both prostate size and the histologic composition of BPH may help to select patients for specific treatment options. Thus, radiologic imaging may eventually play a larger role in the diagnosis and treatment of LUTS in the future. After review of the literature, it appears that routine upper urinary tract imaging in patients with LUTS or BPH is not warranted. Selective use of such imaging tests in patients with BPH and either hematuria, laboratory evidence of renal insufficiency (elevated BUN or creatinine), or a history of urinary tract infection, urolithiasis, previous urinary tract surgery, or congenital or acquired renal disease remains indicated. Local imaging of the prostate can be performed with either MR imaging or TRUS. Although MR imaging provides excellent resolution of internal prostatic anatomy, information with respect to the ratio of glandular to stromal tissue in the prostate, and an accurate estimate of prostate volume, its use in patients with BPH is limited by its high cost and limited availability. In contrast, TRUS remains an important tool in the evaluation of patients with prostatic disease. Similar to MR imaging, TRUS provides excellent images of internal prostatic anatomy and an accurate estimate of prostate volume prior to treatment. In addition, this imaging modality is noninvasive, cost-efficient, easily adapted to office use, and able to provide guidance for transrectal prostate biopsy.

Radiologic anatomy of the prostate gland: a clinical approach.

Familiarity with normal anatomy is critical to interpretation of imaging of the prostate and peri-prostatic structures. This is especially true for MR imaging, which depicts these structures with exquisite detail due to high spatial resolution, superior contrast resolution, multiplanar capability, and large field of view. Anatomic understanding plays a key role in the assessment and management of prostatic disease, and allows evaluation of anatomic disturbances that may result from prostatic disease or therapy, and which may have functional consequences, particularly for continence and potency.

Role of magnetic resonance imaging in fetal surgery.

Prenatal magnetic resonance imaging (MRI) has several advantages over obstetric ultrasound, including a larger field of view, superior soft-tissue contrast, more precise volumetric measurements, and greater accuracy in the demonstration of intracranial abnormalities. Prenatal MRI has been shown to positively and incrementally influence management in a substantial proportion of patients being considered for fetal intervention. Despite these findings, precise indications for prenatal MRI in the setting of fetal surgery are not yet established, because both prenatal MRI and fetal surgery are relatively new techniques that remain in evolution. Conditions in which prenatal MRI appears to contribute to fetal surgical planning and postoperative evaluation are described in this review. These conditions include congenital diaphragmatic hernia, cystic adenomatoid malformation, sacrococcygeal teratoma, complicated twin pregnancies, upper airway obstruction, and myelomeningocele.

Case report: bladder opacification following enteral iopamidol as a sign of occult intestinal infarction.

A case of intestinal infarction due to superior mesenteric artery embolism is described in a 30-year-old female with Crohn's disease. This was accompanied by bladder opacification following enteral iopamidol administered at endoscopic retrograde cholangiopancreatography. The likely mechanism of this finding is transmural and transperitoneal absorption of enteral contrast medium and its significance as a sign of mesenteric ischaemia is discussed.

Diffuse retroperitoneal amyloidosis due to renal cell carcinoma.

The case of a 61-year-old man with haematuria, in whom CT demonstrated a solid renal mass and extensive retroperitoneal infiltration, is presented. This combination of CT findings resulted in significant diagnostic uncertainty. Pathological analysis demonstrated renal cell carcinoma, with secondary amyloidosis in the retroperitoneum. Amyloidosis secondary to renal cell carcinoma has not been previously described as a cause of retroperitoneal infiltration.

Maximum intensity projection images in the detection of simulated pulmonary nodules by spiral CT.

This study was undertaken to investigate the use of maximum intensity projection (MIP) images in the detection of pulmonary nodules by spiral CT (SCT). 40 pulmonary nodules of high density were created by endobronchial deployment of 2 and 4 mm beads in the peripheral airways of five anesthetized dogs. Standard SCT was performed with 5 mm collimation, pitch 2 and reconstruction of contiguous slices. MIP images were generated from overlapped slabs of seven consecutive 3 mm slices, reconstructed at 2 mm intervals and acquired at pitch 2. Scans were reviewed by six radiologists. The data were modelled using ordinal logistic regression for repeated measures, and the Wald chi 2 statistic used to test if there was a difference in nodule detection and reader confidence level between the two techniques. MIP imaging increased the odds of nodule detection by 2.18 (p = 0.0002). Reader confidence level for nodule detection was significantly higher with MIP images (p < 0.00001). MIP images improve the detection rate for small high density pulmonary nodules and increase reader confidence level, when compared with standard SCT.

The aetiology of solitary hot spots in the ribs on planar bone scans.

The aim of this study was to determine the aetiology of solitary hot spots in the ribs found at bone scintigraphy in patients with known extraskeletal malignancy. A group of 34 patients whose bone scans showed a solitary hot spot in a rib were identified retrospectively over a 4-year period. They all had a known extraskeletal malignancy. Aetiology of the rib hot spot was established in 26 patients based on a review of clinical features, radiographic findings and clinical follow-up. In eight cases it remained indeterminate. In 14 (41%) cases, the rib lesion was malignant in origin, 9 were due to metastasis and 5 due to direct spread from intrapulmonary malignancy. In 12 (35%) cases, it was benign. In the remaining 8 (24%) cases, the aetiology was indeterminate. In the subgroup of 14 hot spots confined to the anterior rib end, 5 (36%) were due to malignancy, 4 (28%) were benign and 5 (36%) were indeterminate. We conclude that solitary hot spots in the ribs of patients with known extraskeletal malignancy undergoing bone scintigraphy are frequently (41%) malignant in origin. This also applies when the hot spot is in the anterior rib end (36% malignant). Thus, such hot spots are far more sinister than previously reported and require careful clinical and radiographic evaluation.

Ectopic salivary gland in the posterior triangle of the neck.

Ectopic cervical salivary tissue may present as a discharging sinus if a duct system and cutaneous orifice are present. Where described in previous reports these openings have been located along the anterior border of sternomastoid or in the anterior triangle, making this a differential diagnosis of a branchial sinus. We report on a patient who presented with an ectopic salivary gland in the posterior triangle of the neck.

Musculoskeletal pitfalls and pseudotumours in the pelvis: a pictorial review for body imagers.

Many musculoskeletal abnormalities in the pelvis are first seen by body imagers while reviewing pelvic cross-sectional studies, and some of these abnormalities may mimic malignancy or another aggressive process. This article describes nine musculoskeletal pseudotumours and interpretative pitfalls that may be seen on CT, MRI and ultrasound imaging of the pelvis. Awareness of these pitfalls and pseudotumours may help avoid misdiagnosis and prevent inappropriate intervention or management.

Diagnostic evaluation of cystic pancreatic lesions.

BACKGROUND: Cystic pancreatic neoplasms (CPNs) present a unique challenge in preoperative diagnosis. We investigated the accuracy of diagnostic methods for CPN. MATERIAL AND METHODS: This retrospective cases series includes 70 patients who underwent surgery at a university hospital for presumed CPNs between 1997 and 2003, and for whom a definitive diagnosis was established. Variables examined included symptoms, preoperative work-up (including endoscopic retrograde cholangiopancreatography (ERCP) in 22 cases and endoscopic ultrasound (EUS) in 12), and operative and pathological findings. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) scans (n=50 patients; CT=48; MRI=13) were independently reviewed by two blinded GI radiologists. RESULTS: The final histopathologic diagnoses were mucinous cystic neoplasm (n=13), mucinous cystadenocarcinoma (10), serous cystadenoma (11), IPMN (14), simple cyst (3), cystic neuroendocrine tumor (5), pseudocyst (4), and other (10). Overall, 25 of 70 were malignant (37%), 21 premalignant (30%), and 24 benign (34%). The attending surgeon's preoperative diagnosis was correct in 31% of cases, incorrect in 29%, non-specific "cystic tumor" in 27%, and "pseudocyst vs. neoplasm" in 11%. Eight had been previously managed as pseudocysts, and 3 pseudocysts were excised as presumed CPN. In review of the CT and MRI, a multivariate analysis of the morphologic features did not identify predictors of specific pathologic diagnoses. Both radiologists were accurate with their preferred (no. 1) diagnosis in <50% of cases. MRI demonstrated no additional utility beyond CT. CONCLUSIONS: The diagnosis of CPN remains challenging. Cross-sectional imaging methods do not reliably give an accurate preoperative diagnosis. Surgeons should continue to err on the side of resection.

3D MR spectroscopic imaging in the evaluation of prostate cancer.

The management of prostate cancer is a complex issue with a varying range of treatment options available. Magnetic resonance (MR) imaging of the prostate has been available for sometime but has the limitation of only anatomical evaluation. Three-dimensional MR spectroscopy is emerging as a new and sensitive tool in the metabolic evaluation of prostate cancer. This article reviews the principle, techniques, and methods of evaluation of spectroscopy and also discusses the applications of spectroscopy in the current management of prostate cancer.

Pyelonephritis mimicking colitis on CT: case report.

We report a patient with acute pyelonephritis in whom the dominant computed tomographic findings were ascending colon and cecal wall thickening and pericolonic fat stranding, likely related to contiguous inflammation from the right kidney. To our knowledge, this is the first report of acute pyelonephritis affecting the right colon mimicking colitis on computed tomography.