Tag Archives: General

Bisphosphonate-related Osteonecrosis of the Jaw

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is associated with the use of bisphosphonates to treat severe osteoporosis, and metabolic and oncologic bone conditions, including hypercalcemia associated with malignancy. These agents inhibit osteoclasts, reducing bone resorption and osteolysis, and also possess antiangiogenic properties, reducing blood flow and necrosis. Patients with BRONJ present with pain and exposed, nonvital bone involving the maxillofacial structures. The incidence of BRONJ increases with the duration of treatment, especially with the intravenous route and concomitant steroid therapy. The osteonecrosis usually is participated by dental extraction. When spontaneous, it commonly occurs along the mylohyoid ridge. BRONJ can mimic osteomyelitis and osteoradionecrosis. A history of dental caries and the presence of periosteal elevation can help direct one towards the diagnosis of osteomyelitis. Osteoradionecrosis can be excluded if the patient has not received oropharyngeal radiation therapy. Jaw neoplasm, primary or metastatic, can potentially also mimic BRONJ. Treatment of BRONJ consists of cessation of bisphosphonate drug therapy, antibiotics for secondary infection, and surgical debridement of necrotic sequestra.

Ryan Schwope BROJN1
Figure 1: Axial CT of the facial bones. There is a mixed sclerotic and lytic lesion within the mandible (Figure 1, arrows) with foci of cortical interruption (Figure 2, arrowheads).
Ryan Schwope BROJN 2
Figure 2: Sagital CT of the facial bones. There is a mixed sclerotic and lytic lesion within the mandible (Figure 1, arrows) with foci of cortical interruption (Figure 2, arrowheads).

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Lipoleiomyoma

Ryan Schwope
CT shows a predominantly fat
attenuation, intramural uterine mass. There is rim of surrounding
calcification as well as a few foci of internal soft tissue density at the
superior aspect of the mass 

Ryan Schwope
   MR imaging showed the majority of the uterine mass as hyperintense on T1 weighted imaging (isointense to subcutaneous
fat)

Ryan Schwope
T2 weighted image with fat saturation MRI shows the uterine mass markedly hypointense (isointense to subcutaneous fat)

Ryan Schwope
Post contrast T1 weighted MRI image with fat saturation show mld enhancement of the soft tissue component  along the superior margin of the mass; the majority of the mass is markedly hypointense (isointense to subcutaneous fat)

Uterine
lipoleiomyomas are rare, benign tumors with a variable reported incidence
ranging from 0.03% to 0.2%. The exact etiology of these lesions is
unclear.  It is postulated lipoleiomyomas
either arise from fatty metaplasia of the smooth muscle cells of leiomyomas, or
from misplaced embryonic fat cells in the uterus. CT is highly specific for
the diagnosis when an intrauterine mass is seen containing both macroscopic fat
and soft tissue density. MR can also be confirmatory as the mass will have high
T1 weighted signal which can be confirmed as fat by using a fat suppression. The role of imaging is also to differentiate lipoleiomyoma from an ovarian
teratoma, a much more common entity presenting as a fat-containing pelvic mass.
Lipoleiomyomas require no treatment or follow-up whereas teratomas are
frequently resected. 

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