Magnetic resonance imaging for Human T-cell lymphotropic virus type 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis patients: a systematic review

Abstract

Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis is a chronic progressive neurologic disease, which might be associated with brain and spinal cord atrophy and lesions. Here, we systematically reviewed the brain and spinal cord abnormalities reported by magnetic resonance imaging (MRI) modality on HTLV-1-associated myelopathy/tropical spastic paraparesis patients. Methods: PubMed was searched for all the relevant articles, which used MRI in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis. Included criteria were all the cohort and case series with at least 10 patients. We had no time limitation for searched articles, but only English language articles were included in our systematic review. Exclusion criteria were none-English articles, case reports, articles with less than 10 patients, spastic paraparesis patients with unknown etiology and patients with HTLV-II. Results: Total of 14 relevant articles were extracted after studying title, abstracts and full text of the irrelevant articles. Only 2/14 articles reported brain atrophy incidence. Five out of 14 articles studied the brain lesions prevalence. Spinal cord atrophy and lesions were studied in 6/14 articles.Discussion: According to the extracted data, brain atrophy does not seem to happen frequently in patients with HTLV-1 associated myelopathy/tropical spastic paraparesis. None-specific brain lesions identified in articles are indicative of low specificity of MRI technique despite its high sensitivity. Conclusion: Prevalence of spinal cord lesions and atrophy in these patients might be due to the degenerative processes associated with aging phenomenon. Further and larger studies in endemic areas could more accurately reveal the specificity of MRI in these patients.