AIM: To study the spectrum of imaging appearances on CT and MRI in ankylosing spondylitis patients with HLA B27 positive patients  in kumaon region.

Materials and Methods: This was a prospective study conducted in the department of Radiodiagnosis Government Medical College and Dr Susheela Tiwari Memorial Hospital,Haldwani. This study was carried out on 51 cases of ankylosing spondylitis HLA B27 positive cases. C.T. and MRI features were observed on T1weighted, T2weighted and short tau inversion recovery (STIR) sequences. The Spectrum of imaging was studied on the basis of history, clinical evaluation and characteristic radiological features on C.T. and M.R.I.   

Results: The disease was most commonly seen in adults with a male predominance in 37 (72.5%) cases. Backache (82.4%) was most common clinical feature followed by inflammation in (80%) cases. Lumbar spine was the most common site in 45 (88%) cases with bilaterally symmetrical involvement in 45 (88%) cases. Subchondral sclerosis was better appreciated in C.T. in 34 (66.6%) cases followed by joint erosion in 23 (45%) cases and joint space alteration in 15(29.4%) cases. Whereas, bone marrow oedema 37 (72.5%) cases was better appreciated in M.R.I followed by articular margin irregularity in 34(66.6%) cases and presence of erosion in 32 (62.7%) cases.

Conclusion: Imaging is an integral part in the early detection of disease and optimizing management of affected patients for their better prognosis. CT and MRI plays a decisive role in   the diagnosis and these modalities are also helpful in monitoring the disease.