<prompt> Which is the most reliable investigation in diagnosing a case of Spinal TB?X rayCT guided biopsyMRIMantouxtest  <response>: MRI is the imaging technique of choice in diagnosing spinal TBespecially in detecting spinal cord compression or cauda equina. Spinal TB: Spine is involved in 40 cases of skeletal TB. In children the most common site of skeletal TB is upper thoracic spine and in adults lower thoracic and upper lumbar veebrae are frequently affected. Ref: Harrisons Principles of Internal Medicine, 18th Edition chapter 165. 