MR imaging and US of female urethral and periurethral disease.

The spectrum of female urethral and periurethral disorders includes both benign and malignant entities. Establishing an accurate clinical diagnosis may be challenging because symptoms and physical findings frequently overlap among the various entities. Recent technologic advances in magnetic resonance (MR) imaging and ultrasonography (US) allow more detailed evaluation of urethral and periurethral abnormalities. Advances in MR imaging hardware and pulse sequences allow high-resolution, high-contrast static and dynamic imaging of the female urethral and periurethral region in the context of the entire pelvic floor. Similarly, the introduction of high-resolution surface and intracavitary transducers in conjunction with three-dimensional acquisition have enhanced the role of US in this clinical setting. High-resolution MR imaging and real-time US have exciting potential as tools for more comprehensive analysis of the pathophysiologic features of the complex disorders that affect the female urethra and periurethral tissues.

Atypical imaging appearance of toxoplasmosis in an HIV patient as a butterfly lesion.

In acquired immunodeficiency syndrome (AIDS) patients, differentiating toxoplasmosis and primary central nervous system (CNS) lymphoma remains a clinical and radiographic dilemma. The presence of butterfly lesions crossing the corpus callosum is customarily used to exclude the possibility of toxoplasmosis. We present an AIDS patient who had Epstein-Barr virus (EBV) polymerase chain reaction (PCR) -positive cerebrospinal fluid studies with a butterfly toxoplasmosis lesion confirmed by multiple methods signifying the importance of including toxoplasmosis in the differential diagnosis of butterfly lesions.

Pancreatic cystic lesions: discrimination accuracy based on clinical data and high-resolution computed tomographic features.

OBJECTIVE: To determine the frequency of typical features of pancreatic cystic lesions on high-resolution computed tomography and the combination of features that best influences discrimination. METHODS: Ten computed tomography features of 100 proven pancreatic cystic lesions were retrospectively tabulated by 2 blinded imagers. After final diagnosis was revealed, each lesion was categorized as typical or atypical. Stepwise multivariable logistic regression was used to determine which of 10 imaging and 4 clinical features significantly distinguished between benign and malignant lesions. RESULTS: There were 38 benign cysts and 62 cystic tumors. Serous lesions presented with greater than 6 cysts (83%) and cysts of less than 2 cm (44%). Mucinous lesions presented with cysts of 2 cm or greater (82%) and less than 6 cysts (64%). Pseudocysts, serous, and mucinous lesions presented typically in 77%, 67%, and 64% of cases, respectively. The significant variables in classifying malignant lesions are pancreatitis history, cyst size, symptoms, and calcification pattern (area under the curve, 0.837). CONCLUSIONS: Four specific imaging and clinical features in combination best predict a malignant lesion.

Pancreatic cystic lesions: discrimination accuracy based on clinical data and high resolution CT features.

OBJECTIVE: To determine the accuracy of high-resolution computed tomography in discriminating among pancreatic cystic lesions with and without clinical history. METHODS: Multiphasic high-resolution computed tomographic scans of 100 proven cystic pancreatic lesions were retrospectively reviewed by 2 blinded imagers. Before and after a history of pancreatitis was revealed, readers classified lesions as either nontumor-related or tumor-related. Reviewers also classified lesions as benign or malignant and finally categorized each lesion as serous, mucinous, or other lesion. Diagnostic performance parameters for classification were calculated for each reader with and without history. RESULTS: Sixty-two lesions were tumor-related and 38 were not. Accuracy for classifying tumor-related from unrelated cysts for both reviewers increased (83%-92%, 85%-91%) when unblinded to pancreatitis history. Specificity also significantly increased (66%-88% and 84%) for both reviewers. CONCLUSIONS: Pancreatic-phase computed tomography enabled more than 80% accuracy in discriminating between tumor-related and unrelated lesions and increased with information of pancreatitis history.