Pelvic arterial pseudoaneurysm-a rare complication of Cesarean section: diagnosis and novel treatment

An uncommon cause of delayed postpartum hemorrhage is a pseudoaneurysm of the uterine artery. Pelvic arterial pseudoaneurysm is generally treated by laparotomy and hemostatic sutures or by uterine artery embolization. We describe two cases of late postpartum hemorrhage following Cesarean section, attributed to pelvic arterial pseudoaneurysm, that were successfully treated by direct thrombin injection under ultrasound guidance. Percutaneous or transvaginal ultrasound-guided direct thrombin injection is a simple procedure that does not require any sophisticated surgical or radiological equipment.

Analysis of clustered microcalcifications by using a single numeric classifier extracted from mammographic digital images

RATIONALE AND OBJECTIVES

The authors prospectively tested the performance of a single numeric classifier constructed from a discriminative analysis classification system based on automatic computer-extracted quantitative features of clustered microcalcifications.

MATERIALS AND METHODS

Mammographically detected clustered microcalcifications in patients who had been referred for biopsy were digitized at 600 dpi with an 8-bit gray scale. A software program was developed to extract features automatically from digitized images to describe the clustered microcalcifications quantitatively. The significance of these features was evaluated by using the Wilcoxon test, the Welch modified two-sample t test, and the two-sample Kolmogorov-Smirnov test. A discriminant analysis pattern recognition system was constructed to generate a single numeric classifier for each case, based on the extracted features. This system was trained on 137 archival known reference cases and its performance tested on 24 unknown prospective cases. The results were evaluated by using receiver operating characteristic analysis.

RESULTS

Thirty-seven extracted parameters demonstrated a statistically significant difference between the values for the benign and for the malignant lesions. Seven independent factors were selected to construct the classifier and to evaluate the unknown prospective cases. The area under the receiver operating characteristic curve for the prospective cases was 0.88.

CONCLUSION

A pattern recognition classifier based on quantitative features for clustered microcalcifications at screen-film mammography was found to perform satisfactorily. The software may be of value in the interpretation of mammographically detected microcalcifications.

Hepatic abscess due to occult biliary stones

The advent of radiologic percutaneous drainage of abdominal abscesses has revealed that a significant percentage involve a fistulous communication to other organs or structures. We present two cases in which abscessograms revealed unsuspected fistulous communication to an incompletely or intermittently obstructed biliary tree with retained stones.