PMC5314669_01
Orthopantomogram (panorex) demonstrating multiple lucencies (arrows) in the left mandible
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F1
An orthopantomogram demonstrated lucencies in the mandible [Figure 1].
CT of the mandible. There are well-defined lytic lesions with evidence of cortical destruction (arrow). These findings were initially considered suspicious for osteomyelitis
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F2
A follow-up computed tomography (CT) was performed and showed multiple lytic lesions [Figure 2], with evidence of osseous erosion and destruction of the mandibular cortex.
Bone scan demonstrating multiple areas of abnormally increased uptake including the mandible and right iliac as well as symmetric uptake in the femurs and tibia (arrows). Mild uptake was also present in multiple other locations in the axial and appendicular skeletons. This distribution is highly suggestive of Erdheim-Chester disease
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F3
The bone scan demonstrated increased uptake in the mandible as well as in the right iliac, along with symmetric uptake in the femurs and tibia [Figure 3].
A skeletal survey was performed. Some mild, ill-defined sclerosis was noted in the proximal femora, right iliac (arrow), and cervical spine. The thoracic and lumbar spine were noted to be unremarkable
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F4
A skeletal survey was performed following the bone scan [Figure 4].
MRI findings demonstrating multiple bilateral and symmetric sclerotic foci in the humeri, femurs, and iliac bones (arrows)
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F5
Subsequent whole body magnetic resonance imaging (MRI) redemonstrated the multiple known sclerotic foci in the humeri, femurs, and iliac bones [Figure 5] but did not identify soft tissue involvement.
Findings on PET were very similar to those of the bone scan and showed increased FDG uptake in multiple locations in the skeleton. As in the case of the bone scan, the symmetric uptake in the lower extremities (arrows) is strongly suggestive of ECD
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F6
The patient was subsequently referred for FDG-PET/CT for staging [Figure 6].
MRI of the head, which demonstrated a bulky adenohypophysis with thickening of the pituitary stalk (arrow), a typical finding in ECD
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F7
Given her diagnosis of ECD, the patient underwent MRI of the head [Figure 7] and was found to have bulky adenohypophysis with associated thickening of the pituitary stalk, in keeping with ECD.