MRI features of spinal Fluorosis: Results of an endemic community screening

Objectives: Fluorosis is endemic in many parts of the world. However community studies on MRI features of fluorosis are lacking. The aim of this study was to determine MRI features of spinal changes in a community with endemic fluorosis in the Thar Desert Pakistan.

Methodology: Randomly selected adults from the Village Samorindh, district Tharparker, Sindh, Pakistan, with spinal fluorosis diagnosed on plain x-rays and raised serum fluoride levels were studied from June 2008 to January 2009. MRI was carried out on 0.5 T open magnet MRI system. Features of vertebral body, spinal ligaments, intervertebral disc, facet joints, iliac wings and other incidental findings were noted. Sclerosis was defined as low signal intensity on both T1 and T2 weighted images. Results were described as mean and percentage values.

Results: All the studied 27 subjects complained of back ache without neurological signs. The average age was 43.33 ± 10.45 years; 21 being male (77.8%). The most frequent findings included generalized vertebral sclerosis (24, 88.8%), ligamentum flavum hypertrophy (23, 85%), anterior (20, 74%) and lateral (17, 62.9%) disc herniation, thickened longitudinal ligaments, and narrowing of spinal foramina. Hemangioma was seen in 04(14.8%). The most commonly involved level was L1-2, L4-5 and lower dorsal spine.

Conclusion: Vertebral sclerosis, a combination of premature degeneration with anterior disc herniation and an unusually high frequency of vertebral hemangioma formed the spectrum of MRI findings in subjects with spinal fluorosis having back ache but no neurological findings.