Choledochal cyst presenting during pregnancy is a rare condition, associated with potentially life-threatening complications for both the mother and developing fetus. Clinical symptoms are nonspecific, and radiographic evaluation is complicated by the presence of the gravid uterus. The authors describe a 34-year-old pregnant female presenting in the third trimester with obstructive jaundice and a right upper quadrant mass. Multiplanar and multisequence imaging with MR established the antepartum diagnosis of choledochal cyst, avoiding the use of ionizing radiation during pregnancy.

OBJECTIVE:The objective of this paper is to describe fatigue fractures in the supramalleolar area of the tibia. The spectrum of imaging findings in 14 cases is presented, with emphasis on plain film radiographic findings.DESIGN AND PATIENTS:Fourteen patients with fatigue fractures in the supramalleolar area of the distal tibia were seen in a 6-year period. The 13 men and 1 woman had an age range from 14 to 64 years (mean 30 years). These patients had no underlying conditions that would predispose them to fractures. Sequential plain film radiographs and other special imaging studies (technetium-99m scans and computed tomography) were retrospectively reviewed.RESULTS AND CONCLUSIONS:Initial plain film radiographs showed a horizontal linear band of increased density in only 2 cases, a subtle cortical bulge in 5 cases, a focal "graying" of the cortex in 2 cases, a single layer periosteal reaction in 1 case, and no abnormality in the final 4 cases. Technetium-99m scans were done in 11 cases and showed focal areas of increased uptake in all 11. These areas of increased uptake were vertically orientated in 10. One patient had computed tomography showing cortical thickening around a linear lucency. The spectrum of imaging findings is similar to that seen in fatigue fractures in more common locations. Supramalleolar fatigue fractures should be suspected in patients who have pain in the distal tibia even when initial plain film radiographs are normal. When initial radiographs are normal, technetium-99m scans can confirm the diagnosis.

Spinal tuberculosis, the most common form of skeletal involvement, is increasing in prevalence because of the resurgence of tuberculosis during the past decade in patients with AIDS, the spread of tuberculosis among the homeless, and the expanding immigrant population. Spinal infection is usually the result of hematogenous seeding of the vertebral body, and the diagnosis often remains elusive because of the indolent nature of tuberculous infection. As a result, the radiographic findings and the signs and symptoms are typically far advanced when the diagnosis is finally established. Radiographic manifestations of tuberculous spondylitis include intraosseous and paraspinal abscess formation, subligamentous spread of infection, vertebral body destruction and collapse, and extension into the spinal epidural space. Significant instability and deformity of the spine can result, mandating prompt diagnosis and treatment to prevent permanent neurologic damage. The purpose of this essay is to illustrate the broad spectrum of imaging findings on plain radiographs, bone scans, CT scans, myelograms, and MR images of patients with spinal tuberculosis. The value of MR imaging in determining the extent of disease is demonstrated.

Spontaneous chylothorax, an uncommon manifestation of pulmonary disease, has been described in association with infectious and inflammatory conditions involving the chest, thoracic trauma, and thoracic neoplasms. Isolated chylothorax is a rare manifestation of sarcoidosis and is usually associated with the presence of mediastinal and hilar adenopathy causing obstruction of the thoracic duct. We report a case of recurrent spontaneous chylothorax in a patient with parenchymal sarcoidosis without hilar or mediastinal adenopathy.

Mineralizing microangiopathy, a distinctive histopathologic process involving the microvasculature of the central nervous system (CNS), is usually seen following combined radiation and chemotherapy for the treatment of CNS neoplasms in childhood. CT typically demonstrates calcification within the basal ganglia and subcortical white matter. The areas of calcification may give paradoxically increased signal on T1-weighted MRI due to a surface-relaxation mechanism, and decreased signal on T2-weighted images.

A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described.

A Salmonella typhi abscess within a craniopharyngioma in a 28-year-old woman is reported. CT and MRI demonstration of cerebral edema adjacent to the tumor suggested an atypical presentation of craniopharyngioma.

Renal leiomyoma are rare, benign tumors of the kidney. There is little information about the imaging of these tumors with modern modalities. We present a case of computed tomographic (CT) and magnetic resonance (MR) imaging of a large renal leiomyoma.

Tuberculous meningitis usually results from hematogenous seeding of the central nervous system from a primary pulmonary source of infection. Initially, the meningitic process can mimic a flu-like syndrome, followed rapidly by the development of profound neurologic deficits. Computed tomography scanning or magnetic resonance imaging of the head often demonstrates a characteristic pattern of basal cistern involvement with Mycobacterium tuberculosis. The incidence of tuberculous meningitis in the more developed countries has increased during the past 5 years because of the growing number of cases in patients with acquired immunodeficiency syndrome, the spread among the homeless, and the expanding immigrant population. The significant morbidity and mortality rates associated with tuberculous meningitis--generally considered to be a disease of the past--emphasize the need for greater clinical awareness, early diagnosis, and prompt treatment.

Testicular microlithiasis is a diffuse, benign condition involving both testicles without architectural distortion. Multiple, bright echoes are present on ultrasound examination which rarely cause shadowing. Many associated conditions have been reported in patients with this entity. As this is a benign entity, knowledge of its appearance and associated conditions to prevent unnecessary surgery is important.

The incidence of acute mastoiditis has decreased significantly because we can effectively treat otitis media with oral antibiotics. Inadequate or delayed treatment of otitis predisposes to the development of mastoiditis and more serious, life-threatening complications. Extension of the infectious process beyond the mastoid system can lead to a variety of intracranial and extracranial complications including meningitis, epidural and intracerebral abscesses, vascular thrombosis, osteomyelitis, and abscesses deep within the neck. Signs of clinical deterioration in a patient with otitis media should indicate to the general practitioner that a more serious condition is evolving and surgical intervention may be necessary. Computed tomography is considered the imaging modality of choice for patients with acute mastoiditis because it can define clearly the regional anatomy and provide important diagnostic information.

In a 35-year-old man with clinical features mimicking acute subarachnoid hemorrhage, MRI demonstrated bilateral Lhermitte-Duclos disease.

Intraoperative ultrasound can be used to localize central nervous system lesions such as hematomas, abscesses, aneurysms, and tumors. High-resolution transducers can differentiate between the echogenic pattern of the normal brain parenchyma and the abnormal pattern of the lesion. When removal of the lesion is necessary, ultrasound can provide an accurate means of localization and immediate evaluation of the surgical site. The following case is presented as an example of the growing use of ultrasound in neurosurgery.

A patient with symptomatic bilateral aberrant cervical internal carotid arteries, demonstrated on CT and MRI, is described.

MR demonstration of reversible cerebral lesions in a child with hypertensive encephalopathy caused by Wilms' tumor.D J Shanley and C L SislerAudio Available | Share

Adenoid cystic carcinoma of the airway: MR findings.D J Shanley, R Daum-Kowalski and R L EmbryAudio Available | Share

Osteosarcoma is the most common primary skeletal malignancy of childhood, typically occurring between the ages of 10 and 20. The classic radiographic appearance is that of a mixed lytic and sclerotic lesion originating in the metaphysis of the long bones with cortical destruction, periostitis, and an associated soft tissue mass. Metastatic disease to the lungs is an important prognostic indicator and is found in the majority of patients dying of the disease [1]. We present a child with osteosarcoma of the distal femur who developed extensive metastatic disease involving the chest pleura bilaterally with no other sites of involvement.

Development of pulmonary histiocytosis X after chemotherapy for Hodgkin disease.D J Shanley, K S Lerud and T J LuetkehansAudio Available | Share