'Precipitation sign': a new radiological sign for spinal intramedullary tubercular abscess

Study design: We came across two patients with holocord tuberculosis exhibiting similar radiological picture, which may aid in early diagnosis. Objectives: We have described a new radiological sign for early diagnosis of intramedullary tubercular abscess. Setting: Observations from an endemic zone for tuberculosis (India). Methods: Surgical excision followed by histological and microbiological examination and retrospective correlation of clinical-radiological-surgical and pathological picture. Results: 'Precipitation sign' can be helpful in the diagnosis of intramedullary tuberculosis. Conclusion: Presence of an intradural extramedullary mass at the lower end of the spinal cord associated with holocord T2 hyperintensities of the spinal cord can be called as precipitation sign and should raise the suspicion of intramedullary tubercular abscess.