Learning objectives
To describe radiologic findings of osteoid osteoma,
in particular atypical findings,
and its variants and mimics.
Background
Osteoid osteoma is a small spherical tumor with a diameter of 2 cm or less,
composed of a central zone named nidus which is an atypical bone completely enclosed within a well-vascularized stroma (1).
The peripheral sclerotic reaction zone is composed of osteoblasts,
osteoclasts and dilated capillaries surrounding the nidus.
Peripheral nerve fibers are abundant in and around an osteoid osteoma.
Pain is typically at night and it is promptly relieved by the administration of salicylates.
Tumors are classified as cortical,
medullary or subperiosteal on...
Findings and procedure details
Typical radiographic findings:
In plain radiographs the lesion is characterized by a small nidus surrounded by dense bone; the nidus is mostly seen as a radiolucent area significantly or mildly calcified depending on the disease duration (1).
At CT,
the nidus is well defined and round or oval with low attenuation.
An area of hypoattenuation may be seen centrally with a peripheral reactive sclerosis (3).
At MRI,
the nidus has low to intermediate signal intensity on T1-weighted images and variable signal intensity on T2-weighted images...
Conclusion
To make the correct diagnosis,
it is important to be familiar with the radiologic findings of osteoid osteoma,
its mimics and confusing imaging findings.
Personal information
Dr.
Filippo Barbiera
UO Radiologia - Ospedale "Giovanni Paolo II" - Sciacca - ASP AG2 - Via Pompei,
92019 Sciacca AG
Email:
[email protected]
Dr.
Bruno Murmura
Resident in training.
Università degli Studi di Palermo - DiBiMed - Scienze radiologiche - Policlinico Universitario A.O.U.P.
- Via del Vespro,
129 Palermo
Email:
[email protected]
References
1.
Hashemi J,
Gharahdaghi M,
Ansaripour E,
Jedi F,
Hashemi S.
Radiological Features of Osteoid Osteoma: Pictorial Review.
Iran J Radiol.
2011;8(3):182-189.
DOI:0.5812/kmp.iranjradiol.17351065.3392
2.
Chai JW,
Hong SH,
Choi JY,
Koh YH,
Lee JW,
Choi JA,
Kang HS,
Radiologic Diagnosis of Osteoid Osteoma: From Simple to Challenging Findings.
RadioGraphics May 2010 Volume 30 Issue 3.
http://pubs.rsna.org/doi/full/10.1148/rg.303095120#
3.
Gamba JL,
Martinez S,
Apple J,
Harrelson JM,
Nunley JA.
Computed tomography of axial skeletal osteoid osteomas.
AJR Am J Roentgenol 1984;142 (4):769–772.
4.
Resnick D,
Kyrriakos M,...