PT  - JOURNAL ARTICLE
AU  - B. Thejeel
AU  - C.S. Geannette
AU  - M. Roytman
AU  - D.J. Pisapia
AU  - J.L. Chazen
AU  - S.T. Jawetz
TI  - Patterns of Intrathecal Ossification in Arachnoiditis Ossificans: A Retrospective Case Series
AID  - 10.3174/ajnr.A7764
DP  - 2023 Feb 01
TA  - American Journal of Neuroradiology
PG  - 228--234
VI  - 44
IP  - 2
4099  - http://www.ajnr.org/content/44/2/228.short
4100  - http://www.ajnr.org/content/44/2/228.full
SO  - Am. J. Neuroradiol.2023 Feb 01; 44
AB  - SUMMARY: Arachnoiditis ossificans is an uncommon end-stage appearance of chronic adhesive arachnoiditis. Imaging features of arachnoiditis ossificans are characteristic and should be diagnosed to avoid unnecessary intervention and guide prognosis and management. In this case series, we retrospectively analyzed CT and MR imaging of 41 patients to identify common patterns of intrathecal ossification and present the common etiologies. Thirty-two patients had a confirmed history of spinal instrumentation, 7 were discovered on imaging without prior surgical history, 1 had a history of ankylosing spondylitis, and 1 had trauma. The most frequent site of ossification was at the conus and cauda equina. Four patterns of ossification were identified, including central, nerve root encasing, weblike, and peripheral. Arachnoiditis ossificans is an important, likely under-recognized consideration in patients who present with back pain. Diagnosis can be made readily on CT; MR imaging diagnosis is also possible but may be challenging.AOarachnoiditis ossificans