MRI findings in Hirayama disease

Abstract

The objective of the study was to study the magnetic resonance imaging (MRI) features of Hirayama disease on a 3 Tesla MRI scanner. Nine patients with clinically suspected Hirayama disease were evaluated with neutral position, flexion, contrast-enhanced MRI and fast imaging employing steady-state acquisition (FIESTA) sequences. The spectrum of MRI features was evaluated and correlated with the clinical and electromyography findings. MRI findings of localized lower cervical cord atrophy (C5-C7), abnormal curvature, asymmetric cord flattening, loss of attachment of the dorsal dural sac and subjacent laminae in the neutral position, anterior displacement of the dorsal dura on flexion and a prominent epidural space were revealed in all patients on conventional MRI as well as with the dynamic 3D-FIESTA sequence. Intramedullary hyperintensity was seen in four patients on conventional MRI and on the 3D-FIESTA sequence. Flow voids were seen in four patients on conventional MRI sequences and in all patients with the 3D-FIESTA sequence. Contrast enhancement of the epidural component was noted in all the five patients with thoracic extensions. The time taken for conventional and contrast-enhanced MRI was about 30–40 min, while that for the 3D-FIESTA sequence was 6 min. Neutral and flexion position MRI and the 3D-FIESTA sequence compliment each other in displaying the spectrum of findings in Hirayama disease. A flexion study should form an essential part of the screening protocol in patients with suspected Hirayama disease. Newer sequences such as the 3D-FIESTA may help in reducing imaging time and obviating the need for contrast.

Nosology of Juvenile Muscular Atrophy of Distal Upper Extremity: From Monomelic Amyotrophy to Hirayama Disease—Indian Perspective

“…Hassan et al in 2012 have reported eleven cases of HD from various regions of India, while Sonwalkar et al in 2008 reported eight cases from South India and Raval et al in 2010 reported nine cases from North India [5, 18, 24]. All patients in these series were males.…”

“…Sonwalkar et al reported a mean age of 18.5 years (11–24 years) [18], while Raval et al reported a mean age of 18 years (15–23 years) [24]. Hassan et al reported all patients younger than 25 years (median age 23 years; 19–50 years) except one patient who was 50 years old with disease duration of 2 years.…”

“…These authors reported clinical features characterized by insidious onset, predominantly unilateral upper extremity weakness and atrophy, cold paresis, and no sensory or pyramidal tract involvement [5, 18, 24]. The amyotrophy is unilateral in most patients, asymmetrically bilateral in some, and rarely symmetric in others [23, 24].…”

“…The amyotrophy is unilateral in most patients, asymmetrically bilateral in some, and rarely symmetric in others [23, 24]. Raval et al found unilateral findings in 89% while Sonwalkar et al and Hassan et al found bilateral involvement in the majority of cases (75% and 55%, resp.)…”

Differentiating lower motor neuron syndromes

“…Pathological studies have demonstrated focal degeneration restricted to anterior horn cells in MMA 43. It has been postulated that upper extremity MMA may be a myelopathy related to flexion movements of the neck with resultant ischaemic damage to the anterior horn cells of the cervical cord 44. Alternatively MMA may represent a primary localised neurodegenerative disorder of the anterior horn cell.…”