title: Diffuse phalangeal signal abnormality on magnetic resonance imaging: phalangeal microgeodic disease.
abstract: BACKGROUND
  Phalangeal microgeodic disease is a rare and benign self-limited condition involving the phalanges, often in the setting of cold exposure, with characteristic MR imaging abnormalities. Radiographic case descriptions are predominantly from Asia and Europe, with only seven cases using MR to characterize phalangeal microgeodic disease.
  
  
  OBJECTIVE
  In this study we describe the MR imaging appearance of unusual and striking phalangeal signal abnormality compatible with phalangeal microgeodic disease at our institution in North America.
  
  
  METHODS
  We retrospectively reviewed cases presenting at our institution with unusual or unexplained phalangeal signal abnormalities between 2001 and 2014. We reviewed the MR imaging appearances in conjunction with radiographs and any other available imaging investigations.
  
  
  RESULTS
  Of 189 examinations reviewed during the study period, 8 imaging studies in 6 patients met the study inclusion criteria. Signal abnormality was present in 57 of 112 phalanges (51%), frequently involving the distal phalanges (70%, 28 of 40), followed by the middle phalanges (56%, 18 of 32) and the proximal phalanges (28%, 11 of 40). The pattern of involvement was most commonly diaphysis (38%), followed by metaphysis (32%) and epiphysis (30%). The extent of MR signal abnormality was greater than that suspected based on clinical presentation or on radiographs.
  
  
  CONCLUSIONS
  The presence of unexplained diffuse characteristic marrow involvement of multiple painful phalanges on MR images, often in the setting of cold exposure, should raise the possibility of phalangeal microgeodic disease. Consideration of this diagnosis based on MR findings would lead to a more conservative management and avoid unnecessary invasive diagnostic procedures.
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., MLC 5031, Cincinnati, OH, 45229, USA. rupa.radhakrishnan@cchmc.org.
authors.forename: Rupa
authors.identifier: http://orcid.org/0000-0001-5224-1891
authors.initials: R
authors.lastname: Radhakrishnan
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., MLC 5031, Cincinnati, OH, 45229, USA.
authors.forename: Kathleen H
authors.initials: KH
authors.lastname: Emery
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., MLC 5031, Cincinnati, OH, 45229, USA.
authors.forename: Arnold C
authors.initials: AC
authors.lastname: Merrow
mesh_terms: D000293:Adolescent; D001847:Bone Diseases / Q000000981:diagnostic imaging*; D002648:Child; D003287:Contrast Media; D004487:Edema / Q000000981:diagnostic imaging; D005260:Female; D050278:Finger Phalanges / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D012189:Retrospective Studies; D013577:Syndrome; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Bone marrow edema; Children; Cold exposure; Feet; Hands; Magnetic resonance imaging; Microgeodic syndrome; Phalanges