The Angle of Louis. A potential pitfall ("Louie's Hot Spot") in bone scan interpretation.
Evaluation of 100 consecutive Tc-99m MDP bone scans revealed in 36 patients a well defined area of increased accumulation of radiotracer at the Angle of Louis--the palpable ridge along the anterior surface of the sternum at the fibrocartilaginous junction of the sternum and manubrium. Twenty-five of the 36 patients had comparison radiographs; all were normal. None had sternal pain or a prior history of chest trauma. Increased uptake at the Angle of Louis ("Louie's Hot Spot") is a relatively common finding (36%) and should be recognized as a normal bone scan finding. It should not be confused with increased uptake due to an osseous abnormality, i.e., metastasis, degenerative disease, trauma, etc.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D002648:Child; D004164:Diphosphonates; D005260:Female; D006801:Humans; D008297:Male; D008371:Manubrium / Q000000981:diagnostic imaging; D008875:Middle Aged; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D013249:Sternum / Q000000981:diagnostic imaging*; D013667:Technetium; D013669:Technetium Tc 99m Medronate
D004164:Diphosphonates; D013667:Technetium; D013669:Technetium Tc 99m Medronate