Faculty Bibliography

BACKGROUND:Attempted nonsurgical reduction of ileocolic intussusceptions after 48 hours is controversial because of the low probability of reduction and an increased risk of perforation. We sought to retrospectively identify computed tomography (CT) criteria that may help to predict bowel viability and successful enema reduction in children with ileocolic intussusception. METHODS:Unanticipated intussusception was diagnosed using CT in six children with mild, atypical symptoms of four to seven days' duration at a single institution during a one-year period. All patients underwent laparotomy without prior contrast enema. Surgical findings were compared with preoperative CT scan findings to identify any criteria that may predict successful nonsurgical management. RESULTS:Contrast CT scan findings were diagnostic of ileocolic intussusception. At the time of laparotomy, three children had easily reducible ileocolic intussusception with nonischemic bowel. Two children had irreducible intussusception with ischemic bowel requiring resection, and one child had a difficult reduction of nonischemic but edematous bowel. Preoperative CT scan findings correlated well with intraoperative findings for all patients. Findings of bowel-wall edema of the intussuscipiens and partial small-bowel obstruction shown on CT were associated with intussusception that was nonreducible or difficult to reduce. CONCLUSION/CONCLUSIONS:Patients with prolonged intussusception diagnosed using CT scan may safely undergo contrast enema reduction if no bowel-wall edema of the intussuscipiens or obstruction is demonstrated.

Use of diagnostic imaging studies for evaluation of pregnant patients with medical conditions not related to pregnancy poses a persistent and recurring dilemma. Although a theoretical risk of carcinogenesis exists, there are no known risks for development of congenital malformations or mental retardation in a fetus exposed to ionizing radiation at the levels typically used for diagnostic imaging. An understanding of the effects of ionizing radiation on the fetus at different gestational stages and the estimated exposure dose received by the fetus from various imaging modalities facilitates appropriate choices for diagnostic imaging of pregnant patients with nonobstetric conditions. Other aspects of imaging besides radiation (ie, contrast agents) also carry potential for fetal injury and must be taken into consideration. Imaging algorithms based on a review of the current literature have been developed for specific nonobstetric conditions: pulmonary embolism, acute appendicitis, urolithiasis, biliary disease, and trauma. Imaging modalities that do not use ionizing radiation (ie, ultrasonography and magnetic resonance imaging) are preferred for pregnant patients. If ionizing radiation is used, one must adhere to the principle of using a dose that is as low as reasonably achievable after a discussion of risks versus benefits with the patient.

OBJECTIVE:Our objective was to describe the CT features of spontaneous isolated celiac artery dissection in a series of six otherwise healthy patients with acute abdominal pain. CONCLUSION/CONCLUSIONS:Although once believed rare, isolated spontaneous celiac artery dissection should be considered in the diagnosis of acute abdominal pain, especially in middle-aged adults.

Pulmonary hyalinizing granulomata are rare, noninfectious, fibrosing lesions of the lung, which can mimic metastatic disease radiographically. Their etiology is unknown, but they may be caused by an exaggerated immune response. We report the radiology, long clinical course, and pathology of a patient with pulmonary hyalinizing granuloma who presented with initially asymptomatic pulmonary nodules. Over a 10-year period, the patient developed multiple insidious autoimmune phenomena, including lupus anticoagulant, neuromyotonia, demyelinating sensorimotor polyneuropathy, and eventually, Morvan's syndrome. Such an association has not been previously published to our knowledge.

We report the radiologic and pathologic findings of a newborn with a choledochal cyst and review the etiology, diagnostic considerations, and management of this entity.

OBJECTIVE:The purpose of this pictorial essay is to familiarize radiologists with the clinical functioning, proper anatomic positioning, appearance on radiographs and CT scans, potential complications, and MRI safety issues of several implantable noncardiac pacemaker and stimulator devices. CONCLUSIONS:The use of noncardiac pacemakers and stimulators is rapidly increasing because of the utility of these devices in the management of surgically and medically refractory conditions. Unlike cardiac pacemakers, electrical stimulators are MRI compatible under certain circumstances.